Adverse Reactions After Community Treatment of Onchocerciasis with Ivermectin in Guatemala

Transactions of the Royal Society of Tropical Medicine and Hygiene. Nov-Dec, 1992  |  Pubmed ID: 1287939

Male and female residents on a Guatemalan coffee plantation where Onchocerca volvulus infections were hyperendemic were offered oral ivermectin (100-200 micrograms/kg) as part of a community-wide treatment programme for onchocerciasis. Forty-five persons were treated and then questioned daily for 28 d about changes in their health. Those with complaints were monitored until all signs and symptoms had resolved. Sixty-seven percent complained of some adverse event after treatment; 60% developed observable adverse reactions attributed clinically to ivermectin. No reaction was life-threatening; the most common were oedema (53%) and fever (47%). Expulsion of intestinal helminths was reported by 38%. Almost all reactions began 24-48 h after treatment; their mean duration was 5 d, despite treatment with acetaminophen and antihistamines. Three patients had oedematous changes lasting over 2 weeks. Incidence, but not severity, of reactions was related to the pretreatment density of microfilariae in skin.

Circulating Gonadotrophins During a Period of Restricted Energy Intake in Relation to Body Condition in Heifers

Journal of Reproduction and Fertility. Nov, 1992  |  Pubmed ID: 1339828

Beef heifers, 13 months old, were fed to achieve high (7.6 +/- 0.2 units) or low (3.9 +/- 0.1 units) body condition by feeding them one of two diets for 20 weeks. During week 17 of the growth phase, all heifers were ovariectomized. From week 20 to week 27 (restriction phase), all heifers were fed a daily diet containing 0.071 MJ metabolizable energy kg-1 body weight. At weekly intervals throughout the restriction phase, blood samples were collected at 10-min intervals for 11 h to determine the pattern of secretion of luteinizing hormone (LH), the amount of LH released in response to 750 ng (pituitary responsiveness) and 50 micrograms LH-releasing hormone (LHRH, releasable stores) and mean concentrations of follicle-stimulating hormone (FSH) in the circulation. Body weight declined during the restriction phase in a similar fashion in heifers with high and low body condition and changes in body weight were unrelated to mean concentrations of LH and FSH and frequency of LH pulses. Amplitude of LH pulses and responsiveness to 750 ng LHRH increased in a linear fashion with weight loss in heifers with low but not in those with high body condition. The amount of LH released in response to 50 micrograms LHRH decreased with increasing weight loss in heifers with high but not with low body condition, indicating that releasable pools of LH declined with increased weight loss in heifers with high body condition.(ABSTRACT TRUNCATED AT 250 WORDS)

Activation of Expression of Genes Coding for Extracellular Matrix Proteins in Tat-producing Glioblastoma Cells

Proceedings of the National Academy of Sciences of the United States of America. Oct, 1992  |  Pubmed ID: 1409674

The Tat protein of human immunodeficiency virus type 1 has been increasingly implicated in directly contributing to the disease AIDS by altering the expression of strategic cellular genes. In this study we demonstrate that the presence of the human immunodeficiency virus type 1 regulatory protein Tat is associated with a significant induction in the expression of certain protein components of the extracellular matrix in glial-derived cells. Northern blot analysis reveals that in cells expressing Tat there is a marked elevation in the steady-state RNA levels for fibronectin and types I and III collagen. Metabolic labeling of the Tat-producing cells demonstrates that this induction is also reflected at the level of protein synthesis. Transient transfection experiments indicate that the presence of Tat results in increased transcription of fibronectin and alpha I type I collagen promoters. Possible mechanisms for this phenomenon and their significance with regard to AIDS are discussed.

Occurrence of Ixodes Pacificus (Parasitiformes: Ixodidae) in Arizona

Journal of Medical Entomology. Nov, 1992  |  Pubmed ID: 1460624

Adults and immatures of Ixodes pacificus Cooley & Kohls were collected by flagging vegetation and from lizards during a 3-mo period in the Hualapai Mountain Park, Mohave County, AZ, in 1991. Collections were made at altitudes > or = 2,134 m. Two of 48 gut-salivary gland extracts of adult ticks were positive by IFA using a monoclonal antibody (H5332) specific to Borrelia burgdorferi. These are the first records of I. pacificus and of spirochetes tentatively identified as B. burgdorferi in Arizona.

Exogenous Progesterone and Progestins As Used in Estrous Synchrony Regimens Do Not Mimic the Corpus Luteum in Regulation of Luteinizing Hormone and 17 Beta-estradiol in Circulation of Cows

Biology of Reproduction. Dec, 1992  |  Pubmed ID: 1493164

Our working hypothesis was that the low concentrations of progesterone (P4) and synthetic progestins administered in hormonal regimens to control estrous cycles of cows would have similar effects on secretion of LH and 17 beta-estradiol (E2). In addition, we hypothesized that concentrations of exogenous P4 typical of the midluteal phase of the estrous cycle and the corpus luteum (CL) would have similar effects on LH and E2, and the effects would be different from those of synthetic progestins and low concentrations of P4. Cows (n = 29) were randomly assigned to one of five treatment groups: 1) one Progesterone Releasing Intravaginal Device (1PRID; n = 6); 2) two PRIDs (2PRID; n = 6); 3) norgestomet, as in Syncro-Mate-B regimen (SMB; n = 6); 4) melengestrol acetate (MGA; 0.5 mg/day; n = 5); and 5) control (CONT; n = 6). Treatments were administered for 9 days (Day 0 = initiation of treatment). All cows from 1PRID, 2PRID, SMB, and MGA groups were injected with prostaglandin F2 alpha (PGF2 alpha) on Days 2 and 5 of the treatment period to regress CL. Cows in the 1PRID and SMB groups were also administered exogenous estrogen according to the respective estrous synchronization protocol for these products. Daily blood samples were collected from Day 0 to 35 to determine concentrations of P4. On Day 8, blood samples were collected at 15-min intervals for 24 h to determine pattern of LH secretion. On Day 9, all treatments ceased and cows in the CONT group received injections of PGF2 alpha.(ABSTRACT TRUNCATED AT 250 WORDS)

Microepidemiology of Onchocerciasis in Guatemala: Dispersal and Survival of Simulium Ochraceum

The American Journal of Tropical Medicine and Hygiene. Aug, 1992  |  Pubmed ID: 1503184

Wild Simulium ochraceum females, both blood engorged and non-blood engorged, were collected from human volunteers infected with Onchocerca volvulus, marked with fluorescent dyes, and released from the same locality as they were collected during February and March 1989. A small hyperendemic village located within 0.5 km of streams supporting large populations of S. ochraceum larvae served as the site for both collection and release of adult females. Fifteen sites for the recapture of flies were located within this same village, within two other villages located 1.0 and 3.7 km from it, and at other places spaced approximately 0.25-3.5 km within a coffee agroecosystem. Flies from both groups were recaptured at distances ranging to 3.5 km from the point of release. Non-blood-engorged flies, however, exhibited a greater tendency to disperse away from the release site. Of the total number of blood-engorged flies recaptured, 51.9% were collected at the release point, 25.7% at 1.0 km, and 1.6% at 3.3-3.5 km. The corresponding percentages for non-blood-engorged flies were 26.9%, 40.4%, and 4.4%, respectively. No flies from either group were recaptured at the most distant site, a large village that was 3.7 km away. Marked flies from both groups were recaptured 12-14 days after release, which was sufficient time for the development of infective O. volvulus larvae. A survival rate (4.7%) of marked, blood-engorged flies over the second and third gonotrophic cycles was estimated from the slope of the regression line of the log number of flies recaptured.(ABSTRACT TRUNCATED AT 250 WORDS)

Ivermectin: Reduction in Prevalence and Infection Intensity of Onchocerca Volvulus Following Biannual Treatments in Five Guatemalan Communities

The American Journal of Tropical Medicine and Hygiene. Aug, 1992  |  Pubmed ID: 1503185

Residents of five hyperendemic communities located in the central focus of onchocerciasis in Guatemala were treated with ivermectin (Mectizan) or placebo every six months for 30 months. The effects of treatment on prevalence and the intensity of skin infection (microfilarial skin density [MFD]) were evaluated. Significant and persistent reductions in both of these indices were achieved by coverage of 80.7% of the eligible populations. The highest proportionate reductions in both indicators of infection occurred after the first treatment, followed by more gradual decreases through the fourth treatment. In one community in which the mean coverage was 92.7%, prevalence decreased from 74.0% at pretreatment to 34.9% after four treatments, while the MFD decreased from 7.8 to 2.0; reductions of 52.8% and 74.3% from pretreatment values, respectively. In every ivermectin-treated community except one, in which drug acceptance was low, the mean community MFD values were reduced to the level associated with low infectiousness for the vector, Simulium ochraceum. Moreover, the category of MFD associated with high vector infectiousness was reduced at least ten-fold over the pretreatment level. One community had low participation during the first two treatments (32.8% and 22.7% of those eligible). This increased to 55.2% at the third treatment because of implementation of an educational program describing both the disease and the beneficial effects of ivermectin and because skin biopsies and nodulectomies were not performed. Secondary reaction rates for all communities were 29.5%, 9.9%, 10.3%, 8.2%, and 7.1% for the first through fifth treatments, respectively. Pruritus was the most common (34.0%) secondary reaction, followed by facial edema (31.8%). All reactions were classified as mild to moderate. Recommendations for mass distribution of ivermectin in Guatemala are given.

The Effects of Repetitive Community-wide Ivermectin Treatment on Transmission of Onchocerca Volvulus in Guatemala

The American Journal of Tropical Medicine and Hygiene. Aug, 1992  |  Pubmed ID: 1503186

The effects of biannual ivermectin treatment at the community level on transmission of Onchocerca volvulus during the dry season were measured over a 30-month period in Guatemala. In the Los Tarrales Transmission Zone, an area encompassing three villages, significant changes occurred in both the prevalence and quantity of infection in the Simulium ochraceum vector population. These included a 76% reduction in females with infective stage larvae (L3S) and an 80% reduction in number of L3S per 1,000 parous flies. Significant reductions in both the mean infective biting density (IBD) and mean transmission potential (TP) also occurred. In Santa Emilia, the prevalence of infection with L3S in S. ochraceum was significantly reduced by 77% from the baseline value. The number of O. volvulus L3S per 1,000 parous flies was also reduced by 92%. Changes in both the IBD and TP were substantial but not significant due to the high degree of variance in the occurrence of O. volvulus L3S in the vector population. This was due, in part, to the movement of infected migrant workers into the finca (coffee farm). In Los Andes, four recurrent treatments successfully blocked transmission of infective stage larvae. Prevalence (flies with all stages of developing larvae) in the vector population was reduced by 89% over the two-year period; yearly reductions in both the IBD and TP were also highly significant, ultimately ending in zero values. This finding is particularly striking since prior to treatment, Los Andes exhibited the highest IBD of the three study locations and the second highest TP.

Morphological and Functional Classification of the Hemocytes of Adult Female Simulium Vittatum (Diptera: Simuliidae)

Journal of Medical Entomology. May, 1992  |  Pubmed ID: 1625294

Morphology and function of the hemocytes of 1-d-old, female Simulium vittatum Zetterstedt were studied using light and scanning electron microscopy. Four types of hemocytes, comparable with those of other medically important Diptera, were identified: prohemocytes, plasmatocytes, granulocytes, and spherulocytes. Plasmatocytes and granulocytes contained neutral red granules, but only granulocytes exhibited significant acid phosphatase activity. Plasmatocytes and granulocytes were identified as the primary phagocytes: plasmatocytes and granulocytes of bacteria in vitro and granulocytes of human red blood cells in vivo. Granulocytes also were observed attached to and degranulating into fat body and hemopoieticlike tissue fragments, perhaps assisting in the mobilization of nutrients for egg development and in the release of immature hemocytes into circulation.

Cloning and Characterization of the Gene Encoding the IDH1 Subunit of NAD(+)-dependent Isocitrate Dehydrogenase from Saccharomyces Cerevisiae

The Journal of Biological Chemistry. Aug, 1992  |  Pubmed ID: 1644826

NAD(+)-dependent isocitrate dehydrogenase from Saccharomyces cerevisiae is composed of two nonidentical subunits, designated IDH1 and IDH2. The gene encoding IDH2 was previously cloned and sequenced (Cupp, J.R., and McAlister-Henn, L. (1991) J. Biol. Chem. 266, 22199-22205), and in this paper we describe the isolation of a yeast genomic clone containing the IDH1 gene. A fragment of the IDH1 gene was amplified by the polymerase chain reaction method utilizing degenerate oligonucleotides based on tryptic peptide sequences of the purified subunit; this fragment was used to isolate a full length IDH1 clone. The nucleotide sequence of the IDH1 coding region was determined and encodes a 360-residue polypeptide including an 11-residue mitochondrial targeting presequence. Amino acid sequence comparison between IDH1 and IDH2 reveals a 42% sequence identity, and both IDH1 and IDH2 show approximately 32% identity to Escherichia coli NAD(P)(+)-dependent isocitrate dehydrogenase. To examine the function of the IDH1 subunit and to determine the metabolic role of NAD(+)-dependent isocitrate dehydrogenase the IDH1 gene was disrupted in a wild type haploid yeast strain and in a haploid strain lacking IDH2. The IDH1 disruption strains expressed no detectable IDH1 as determined by Western blot analysis, and these strains were found to lack NAD(+)-dependent isocitrate dehydrogenase activity indicating that IDH1 is essential for a functional enzyme. Over-expression of IDH1 in a strain containing IDH2 restored wild type activity but did not result in increased levels of activity, suggesting that both IDH1 and IDH2 are required for a functional enzyme. Growth phenotype analysis of the IDH1 disruption strains revealed that they grew at a reduced rate on the nonfermentable carbon sources examined (glycerol, lactate, and acetate), consistent with NAD(+)-dependent isocitrate dehydrogenase performing a critical role in oxidative function of the citric acid cycle. In addition, the IDH1 disruption strains grew at wild type rates in the absence of glutamate, indicating that these strains are not glutamate auxotrophs.

Treatment of Onchocerciasis with Ivermectin in Central America

Parasitology Today (Personal Ed.). Jun, 1992  |  Pubmed ID: 15463619

The success o f ivermectin in controlling transmission of Onchocerca volvulus in Guatemala suggests a broader role for this drug than morbidity control alone. In this article Ed Cupp reviews recent findings from a three-year pilot study in that country which evaluated the effects of recurrent semiannual treatment on several important factors associated with the biology o f river blindness. These results illustrate the range o f beneficial effects that occur not only for this disease but for other parasitisms when this drug is administered at the community level.

CO(2) Lidar Backscatter Profiles over Hawaii During Fall 1988

Applied Optics. Aug, 1992  |  Pubmed ID: 20725465

Aerosol and cloud backscatter data, obtained over a 24-day period in fall 1988 with the National Oceanic & Atmospheric Administration's Doppler lidar at 10.59-microm wavelength, are analyzed by using a new technique to lessen biases that are due to dropouts. Typical backscatter cross sections were significantly lower than those routinely observed over the continental United States, although episodic backscatter enhancements caused by cirrus and mineral dust also occurred. Implications of these data on the proposed Laser Atmospheric Wind Sounder wind profiling satellite sensor are discussed.

Prostate-specific Antigen, Digital Rectal Examination, and Transrectal Ultrasonography: Their Roles in Diagnosing Early Prostate Cancer

Mayo Clinic Proceedings. Mayo Clinic. Mar, 1993  |  Pubmed ID: 7682639

In this article, we review the current status of early detection of prostate cancer. From existing data in the medical and urologic literature, we developed an algorithm that uses the three current methods of detection: digital rectal examination (DRE), determination of the prostate-specific antigen (PSA) value, and transrectal ultrasonography (TRUS). Prostatic malignant disease is an increasing medical problem in the United States. The potential for cure is optimized by early detection and treatment of organ-confined disease. Mass screening for prostate cancer in asymptomatic men cannot be advocated until a decrease in the mortality rate is established by randomized, controlled studies; however, these data will be unavailable for at least 15 years. In the meantime, clinicians must prudently use DRE, PSA, and TRUS for early detection. Current data indicate that the PSA level is as effective as or more effective than DRE for the detection of prostate cancer. These two methods do not always detect the same malignant tumor; therefore, the combined use of DRE and PSA testing provides a more complete evaluation of the prostate gland for malignant involvement. TRUS is more costly and does not add appreciable detectability when results of both the DRE and the PSA determination are normal. Thus, TRUS is best reserved for patients who have abnormal results of DRE or increased PSA values.

Phenotypic and Functional Analysis of T-cell Precursors in the Human Fetal Liver and Thymus: CD7 Expression in the Early Stages of T- and Myeloid-cell Development

Blood. Dec, 1993  |  Pubmed ID: 7694684

It has been proposed that the CD7 molecule is the first antigen expressed on the membrane of cells committed to the T-cell lineage during human fetal T-cell ontogeny. To further identify the pre-T cell subpopulation that migrates to the thymus early in ontogeny, we analyzed the phenotypic and functional characteristics of the fetal liver populations separated on the basis of CD7 expression. Three populations expressing different levels of CD7 were observed: CD7bright, CD7dull, and CD7-. A CD7bright population depleted of mature T, B, and myeloid cells (lineage negative, lin-) and mostly composed of CD56+ CD34- natural killer cells did not mature into T cells in a fetal thymic organ culture (FTOC) assay and was devoid of myeloid progenitors in a clonal colony-forming cell assay. In contrast, the CD7-/dull CD34+ lin- populations were capable of differentiating into phenotypically mature T cells after injection into FTOC and contained early myeloid progenitors. Here we phenotypically compared the fetal liver CD7 populations with the most immature fetal thymic subset that differentiated in the FTOC assay, namely the triple negative (TN, CD3-CD4-CD8-) thymocytes. Fetal TN lin- expressed high levels of CD34 marker and were further subdivided by their expression of CD1 antigen, because CD1- TN thymocytes express higher levels of CD34 antigen compared with CD1+ TN cells. CD1- lin -TN thymocytes are characterized by expressing high levels of CD2, CD7, and CD34 markers and dull levels of CD5, CD10, and CD28 molecules. We could not find fetal liver pre-T cells with a phenotype equivalent to that of TN thymocytes. Our data show that CD7 does not necessarily identify T-cell precursors during fetal T-cell development and strongly support the hypothesis that the acquisition of early T-cell markers as CD2, CD28, and CD5 molecules on the cell surface of T-cell progenitors takes place intrathymically.

Modulation of Murine Immunological Responses by Salivary Gland Extract of Simulium Vittatum (Diptera: Simuliidae)

Journal of Medical Entomology. Sep, 1993  |  Pubmed ID: 8254643

The influence of Simulium vittatum Zetterstedt salivary gland extract on several immunological mechanisms was investigated in murine model hosts (laboratory mice). These mechanisms included the expression of major histocompatibility complex class II cell surface molecules, the in vitro mitogen responsiveness of lymphoid cells, and the antibody responses to heterologous foreign antigens (sheep erythrocytes). Experiments were designed to determine the influence of salivary gland extract following in vivo inoculation or in vitro inclusion in cell culture. In vivo inoculation of salivary gland extract reduced the percentage of Ia+ cells in spleen cell populations, although this difference was ameliorated by a 2 d in vitro culture period, regardless of whether salivary gland extract was included in culture. Salivary gland extract had no effect on Ia expression by cells derived from regional lymph nodes or the skin (epidermis). In vivo inoculation with salivary gland extract did not affect the responsiveness of splenic lymphocytes to mitogens, whereas in vitro exposure to salivary gland extract reduced both T and B cell mitogenesis. Finally, antibody responses to sheep erythrocytes were enhanced if salivary gland extract was included as a coinoculant, although this was expressed only at the systemic level regardless of the route of antigen delivery. In light of these results, immunomodulatory functions of black fly saliva are postulated; they are operative at different levels on different subcompartments of the immune system, possibly via cytokine modulation.

Chromosomal Diagnostic Criteria for Some Members of Simulium Damnosum Complex in East Africa

Tropical Medicine and Parasitology : Official Organ of Deutsche Tropenmedizinische Gesellschaft and of Deutsche Gesellschaft Für Technische Zusammenarbeit (GTZ). Sep, 1993  |  Pubmed ID: 8256090

Identification of Simulium damnosum s.l. vectors of onchocerciasis demands adequate knowledge of the chromosomal features that distinguish human-biting members from nonanthropophilic forms. In this study, 955 S. damnosum larvae collected from various geographical locations in Tanzania were chromosomally analyzed. 358 larvae from small mountain streams in the northeast and central regions of Tanzania, were identified as mainly Nyamagasani and Sanje forms, with only one Kiwira form. 378 larvae from plain and lowland rivers, also in the northeast and central regions, were identified as Nkusi, Kisiwani and Kibwezi forms. Chromosomal examination of 219 larvae from the southern highlands zone revealed the presence of Kiwira and Nyamagasani forms. A further 27 larvae of S. damnosum complex collected from 5 rivers in Uganda were identified as Sebwe and Nkusi forms. Chromosomal photomicrographs on which the distinguishing characters were based are provided. These observations are discussed in the light of previous studies carried out on the S. damnosum cytological forms in Eastern Africa.

Pregnancy Rate is Greater when the Corpus Luteum is Present During the Period of Progestin Treatment to Synchronize Time of Estrus in Cows and Heifers

Biology of Reproduction. Nov, 1993  |  Pubmed ID: 8286577

Our hypothesis was that conception in bovine females would be enhanced if the corpus luteum was present during the period of progestin treatment to synchronize estrus. In this study, 67 heifers (one replicate) and 124 cows (two replicates) were randomly assigned to one of two treatment groups. Seven days after estrus (Day 0), all animals were implanted with norgestomet and the implant remained in place for 10 days. All implants were removed on Day 17. Cows and heifers in one group received prostaglandin F2 alpha (PGF2 alpha) on Day 7 of the estrous cycle (PG 7; norgestomet without corpus luteum), and animals in the second group received PGF2 alpha on Day 17 (day of implant removal; PG 17; norgestomet with corpus luteum). All heifers and cows exhibiting behavioral estrus were artificially inseminated 12 h after estrus was detected during a 7-day period following removal of norgestomet. Blood samples were collected from cows of replicate 1 to determine serum concentrations of progesterone and 17 beta-estradiol. Percentage of females that had calves as a result of artificial insemination was greater (p < 0.01) in the PG 17 group (87% and 78% cows [two replicates] and 58% heifers) compared to the PG 7 group (31% and 44% cows [two replicates] and 41% heifers).(ABSTRACT TRUNCATED AT 250 WORDS)

Evidence for Stimulation of the Transforming Growth Factor Beta 1 Promoter by HIV-1 Tat in Cells Derived from CNS

Oncogene. Aug, 1993  |  Pubmed ID: 8336945

Infection by human immunodeficiency virus type 1 (HIV-1), the etiologic agent of the acquired immunodeficiency syndrome (AIDS), is often complicated with a high incidence of neurologic disorders. It is believed that HIV-1, in addition to infecting both macroglial and microglial cells, may influence the expression of several strategic genes of uninfected neighboring or latently infected brain cells. It is suspected that the viral-encoded transregulatory protein, Tat, facilitates cross-communications between these cells. In support of this concept, earlier studies demonstrated that Tat is released from the infected cells, and has the capacity to be taken up by the uninfected cells and exert its biological activity on the responsive gene. Recent studies in several laboratories suggest the involvement of Tat in altering the expression of a limited number of cellular regulatory factors which, in turn, may mediate the altered physiology of the cells. In this communication, we demonstrate the ability of the HIV-1 Tat protein to increase expression of transforming growth factor beta 1 (TGF-beta 1), a cytokine with potent immunosuppressive activity, in human astrocytic glial cells. Implications of the Tat-mediated induction of TGF-beta 1 expression and cytokine involvement in the regulation of immune response and central nervous system (CNS) pathology are discussed.

Antibody Responses of BALB/c Mice to Salivary Antigens of Hematophagous Black Flies (Diptera: Simuliidae)

Journal of Medical Entomology. Jul, 1993  |  Pubmed ID: 8360895

The humoral antibody responses to salivary antigens of Simulium vittatum Zetterstedt were investigated in a BALB/c mouse laboratory model. Production of antisera was stimulated by intraperitoneal immunization with salivary gland extract or by feeding flies directly on depilated mice. Antibody responses in these two groups of mice were compared by western blotting, thus characterizing "true" salivary immunogens present in salivary gland extract. Immunized mice developed IgG, IgM, and IgE antibodies which recognized several salivary gland components, ranging in molecular weight between 26 and 67 kDa. Sera from bitten mice recognized fewer antigens, indicating that some components of the salivary gland extract were poorly immunogenic or absent from the saliva secreted during blood feeding. Antisera raised against S. vittatum also were used to identify cross-reactive immunogens and allergens in salivary gland extracts from other New World simuliids (Simulium argus Williston, S. metallicum Bellardi, and S. ochraceum Walker). SDS-PAGE protein profiles indicated a high degree of similarity between salivary gland extract of S. vittatum and S. argus, and several cross-reacting antigens were identified by western blotting. In contrast, protein profiles of S. ochraceum and S. metallicum differed from the former species, both qualitatively and quantitatively. Antisera demonstrated a low degree of cross-reactivity against salivary gland extract of S. ochraceum, whereas no cross-reactivity was detected against S. metallicum. These observations were confirmed using a monoclonal antibody raised against S. vittatum salivary gland extract (designated SVSG.1.F10), which showed cross-reactivity against S. argus but failed to recognize salivary gland components of either S. ochraceum or S. metallicum.

Kinetic Analysis of NAD(+)-isocitrate Dehydrogenase with Altered Isocitrate Binding Sites: Contribution of IDH1 and IDH2 Subunits to Regulation and Catalysis

Biochemistry. Sep, 1993  |  Pubmed ID: 8369302

NAD(+)-dependent isocitrate dehydrogenase from Saccharomyces cerevisiae is an allosterically regulated enzyme that exists as an octamer composed of two nonidentical subunits, designated IDH1 and IDH2. To determine the contribution of each subunit to regulation and catalysis, a conserved serine residue at the proposed active site of each subunit was mutated to alanine. This mutation in IDH1 resulted in a 6-fold decrease in Vmax and a decrease in cooperativity, but little change in S0.5 for isocitrate. The mutant IDH2, in contrast, exhibited a 60-fold decrease in maximal velocity and a 2-fold reduction in S0.5 for isocitrate, but the cooperativity was unaffected. Responses to the allosteric modifier AMP also differed for the two mutant enzymes. The IDH1 mutant enzyme was not activated by AMP, whereas the IDH2 mutant enzyme exhibited an increase in isocitrate affinity in the presence of AMP similar to that observed with the wild-type enzyme. On the basis of these kinetic results, a model is presented which proposes that IDH1 functions as a regulatory subunit while IDH2 functions in catalysis. To determine if IDH1 or IDH2 alone is catalytically active, we also expressed the individual subunits in yeast strains in which the gene encoding the other subunit had been disrupted. Mitochondrial extracts from strains overexpressing solely IDH1 or IDH2 contained no detectable activity in the presence or absence of AMP. Gel filtration of these extracts showed that both IDH1 and IDH2 behaved as monomers, suggesting that the major subunit interactions within the octamer are between IDH1 and IDH2.

Increasing Exogenous Progesterone During Synchronization of Estrus Decreases Endogenous 17 Beta-estradiol and Increases Conception in Cows

Biology of Reproduction. Aug, 1993  |  Pubmed ID: 8373944

The objectives of this study were to determine the effects of dose of exogenous progesterone (P4) prior to artificial insemination on concentrations of 17 beta-estradiol (E2) and on conception rates in bovine females. Heifers (n = 100) and cows (n = 100) received P4-releasing intravaginal devices (PRIDs) to produce two different circulating concentrations of P4. All animals received a single PRID 10 days before (Day-10) the start of the breeding season (Day 0). In animals that received the low dose of P4 (1 PRID, target concentration of 2-3 ng/ml of plasma), the original PRID remained in place for 10 days. In animals that received the larger dose of P4 (2 PRIDs, target concentration of 5-8 ng/ml of plasma), an additional PRID was inserted on Day -9. To maintain concentrations of P4 in the 2-PRID group, the PRIDs inserted on Days -10 and -9 were replaced with new PRIDs on Days -5 and -4, respectively. Prostaglandin F2 alpha (25 mg) was administered to all animals on Days -9 and -3 to remove the endogenous source of P4. Following PRID removal, animals were artificially inseminated 12 h after signs of behavioral estrus were observed. A treatment-by-day interaction (p < 0.0001) was observed for concentrations of P4 in circulation of both heifers and cows. Animals that received 2 PRIDs had greater (p < 0.001) concentrations of P4 by Day-8 of treatment than animals that received 1 PRID. In cows that received 1 PRID, concentrations of E2 increased 2.4-fold from Day-10 (6.8 +/- 1.0 pg/ml) to Day-2 (16.7 +/- 1.4 pg/ml).(ABSTRACT TRUNCATED AT 250 WORDS)

Human Papillomavirus Infection and Intraepithelial, in Situ, and Invasive Carcinoma of Penis

Urology. Aug, 1993  |  Pubmed ID: 8396280

The role of human papillomavirus (HPV) infection and other reported cofactors in the genesis, evolution, and clinical manifestations of precancerous and cancerous squamous cell lesions of the penis were studied in 34 men. Clinically, all lesions demonstrated aceto-whitening. Histologic changes of HPV infection formed a field-of-change that involved the components of the preputial cavity in all patients. These changes were associated with minor grades of penile intraepithelial neoplasia (PIN I and II) in 19 patients, major grades of PIN/carcinoma in situ (PIN III/Tis) in 7, and invasive squamous cell carcinoma (SCCa, Stages T2 and T3) in 8. Most of the patients (79.4%) were heavy smokers; 52.9 percent had a history of HPV infection, PIN, or invasive penile SCCa; and 60 percent of 30 patients had female sexual partners who had HPV-related genital neoplasia. A pilot virologic study of specimens obtained from 20 representative patients utilizing polymerase chain reaction amplification detected HPV DNA in 80 percent. Laser therapy was aimed at the entire field-of-change in 30 patients; recurrent minor-grade PIN or SCCa developed in 2 of 23 patients (8.7%) followed for up to three years. Of the 4 remaining patients treated with local excision or partial penectomy, 3 (75%) had development of recurrent minor-grade PIN when followed for up to four years. The combination of the host of carcinogenic factors and currently rampant immunologic disorders will likely lead to an increase in the historically low incidence of SCCa of the penis in the United States.

Yearling Bulls Shorten the Duration of Postpartum Anestrus in Beef Cows to the Same Extent As Do Mature Bulls

Journal of Animal Science. Feb, 1993  |  Pubmed ID: 8440648

The objective of this study was to determine whether yearling bulls, when pastured with cows, reduced the duration of postpartum anestrus to the same extent as did mature bulls. This experiment was conducted over a 3-yr period. Cows were stratified by parity group to achieve 37% 2-yr-old and 63% mature (> 2-yr-old) cows within each treatment group (approximately 50 cows per treatment per year). Cows were assigned in the order in which they calved to one of three treatment groups: 1) isolated from bulls (NBE; n = 158); 2) exposed to mature bulls that were > 3 yr of age (MBE; n = 154); or 3) exposed to bulls that were 1 yr of age (YBE; n = 152). Beginning the 2nd wk after calving, cows were pastured with either sterile bulls that were 1 yr (YBE) or > 3 yr of age (MBE) (three bulls per treatment group). Blood samples were collected twice weekly from late March until mid-July each year. Cows with serum concentrations of progesterone > 1 ng/mL for two consecutive sampling periods were assumed to have initiated estrous cycles after calving. Duration of postpartum anestrus in cows exposed to yearling bulls (YBE = 61.8 +/- 1.8 d) did not differ (P > .10) from duration of postpartum anestrus in cows exposed to mature bulls (MBE = 59.5 +/- 1.7 d). Duration of postpartum anestrus was shorter (P < .01) for cows exposed to bulls (MBE+YBE = 61.0 +/- 1.7 d) than for cows isolated from bulls (NBE = 72.3 +/- 1.8 d).(ABSTRACT TRUNCATED AT 250 WORDS)

Anticoagulant Activity in Salivary Gland Extracts of Black Flies (Diptera: Simuliidae)

Journal of Medical Entomology. Nov, 1994  |  Pubmed ID: 7815406

Anticoagulant activity was determined in salivary gland extracts from four species of black flies, i.e., Simulium vittatum Zetterstedt, Simulium argus Williston, Simulium metallicum Bellardi, and Simulium ochraceum Walker. Inhibition of coagulation factor Xa occurred among all four, whereas thrombin inhibition was detected in S. argus and S. vittatum only. Both bovine and human alpha-thrombins were inhibited with the highest activity occurring with S. argus salivary gland extracts. Factor Xa inhibition was highest in S. ochraceum, an anthropophilic species and vector of Onchocerca volvulus, and lowest in S. vittatum, a primiparous autogenous species that is also zoophilic. Total soluble salivary gland extract protein also varied among the four species with the highest concentration measured in S. ochraceum and the lowest in S. vittatum. A positive correlation was observed between the amount of soluble protein and percentage of inhibition of factor Xa for the four species.

Ovarian Follicular Development in Prepubertal Heifers is Influenced by Level of Dietary Energy Intake

Biology of Reproduction. Nov, 1994  |  Pubmed ID: 7849182

Objectives were twofold: 1) to determine the chronology of development of dominant ovarian follicles during the peripubertal period in heifers and 2) to determine whether feeding a diet with low energy content that delays onset of puberty alters chronology of dominant ovarian follicular development in peripubertal heifers. Ten heifers of composite breeding (1/4 Angus, 1/4 Hereford, 1/4 Red Poll, 1/4 Pinzgauer) were randomly assigned, at 8 mo of age, to receive a diet designed to produce 0.9 (n = 5) or 0.3 (n = 5) kg body weight gain per day for the duration of the experiment. To characterize changes in size of ovarian follicles, real-time linear ultrasonography of ovaries was conducted in all heifers every other day until puberty occurred. Blood samples were collected weekly to determine concentrations of progesterone and 17 beta-estradiol. Determination of time of puberty was based on increased concentrations of progesterone, ultrasound depiction of ovulation, and subsequent presence of a corpus luteum. Size of the dominant ovarian follicles differed prior to puberty (p < 0.03); diameter of the dominant ovarian follicle was greater in all heifers as the first ovulation approached as compared to earlier in prepuberty. Heifers fed the greater amount of energy exhibited larger dominant ovarian follicles at a younger age in comparison to heifers fed the lower amount of energy.(ABSTRACT TRUNCATED AT 250 WORDS)

Luteinizing Hormone Has a Role in Development of Fully Functional Corpora Lutea (CL) but is Not Required to Maintain CL Function in Heifers

Biology of Reproduction. Dec, 1994  |  Pubmed ID: 7888502

We tested the hypothesis that endogenous pulses of LH have a role in development and maintenance of CL during the estrous cycle of the bovine female. Twenty heifers were synchronized to estrus by treating two times with prostaglandin F2 alpha 11 days apart (Day 0 = behavioral estrus). Heifers were then randomly assigned to one of four treatments (n = 5/group). Heifers were treated with an antagonist to LHRH (LHRH-Ant; N-Ac-D-Nal[2]1,4Cl-D-Phe2,D-Pal[3]3,D-Cit6,D-Ala10- LHR H; 10 micrograms/kg body weight) or vehicle (5% mannitol) once every 24 h: 1) LHRH-Ant Days 2-7, 2) LHRH-Ant Days 7-12, 3) LHRH-Ant Days 12-17, 4) no LHRH-Ant (control). Blood samples were collected from the jugular vein twice daily on Days 0-24, and area under the profile of progesterone in circulation during the luteal phase of the estrous cycle was characterized from the start of each treatment period until the demise of CL or Day 24, whichever came first. Luteolysis was considered to have occurred when three consecutive samples contained less than 1 ng progesterone/ml plasma. Areas under the profile of progesterone in circulation during the luteal phase of the estrous cycle were compared to those of heifers from the control group for the same period. LHRH-Ant treatment diminished LH pulses in all treatment groups compared to control (p < 0.05). Treatment with LHRH-Ant on Days 2-7 diminished function of CL (3.72 +/- 0.93 vs. 7.36 +/- 1.02 units, respectively; p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Modulation of Murine Cellular Immune Responses and Cytokines by Salivary Gland Extract of the Black Fly Simulium Vittatum

Tropical Medicine and Parasitology : Official Organ of Deutsche Tropenmedizinische Gesellschaft and of Deutsche Gesellschaft Für Technische Zusammenarbeit (GTZ). Jun, 1994  |  Pubmed ID: 7939161

Salivary gland extract (SGE) of the blood-feeding black fly Simulium vittatum is known to modulate immunological responses. In the present study, the ability of S. vittatum SGE to modulate responses during heterologous antigenic challenge was investigated in a murine model, with particular emphasis on characterizing the patterns of cytokine response. Mice were injected repeatedly with SGE or saline (sham), then challenged with the T dependent antigen ovalbumin (OVA) to generate antigen-specific lymphoblasts. Spleen cells from OVA-primed mice were then co-cultured with OVA in vitro to stimulate cytokine secretion. Cells from mice that had been injected with SGE prior to OVA challenge produced lower levels of interleukins 5 and 10 (IL-5 and IL-10) in in vitro culture, when stimulated with OVA, compared to mice that had been sham-injected with saline. Levels of IFN-gamma, IL-2 and IL-4 did not differ significantly between SGE- and saline-injected groups. Mice injected repeatedly with SGE prior to OVA challenge had fewer circulating eosinophils than sham-injected mice, while other leukocyte levels were unaffected by SGE. Prior exposure to SGE did not affect levels of serum IgE or IgA significantly. The effect of SGE on the ability of murine spleen cells to respond in vitro to the recombinant cytokines IL-2 and IL-4 was also investigated. Naive spleen cells pre-incubated with SGE proliferated less in response to both IL-2 and IL-4 in in vitro culture than cells pre-incubated with saline as a control.(ABSTRACT TRUNCATED AT 250 WORDS)

Cytotaxonomy of the Simulium Damnosum Complex and Description of New Cytotypes in the Tukuyu Focus, Southwest Tanzania

Tropical Medicine and Parasitology : Official Organ of Deutsche Tropenmedizinische Gesellschaft and of Deutsche Gesellschaft Für Technische Zusammenarbeit (GTZ). Jun, 1994  |  Pubmed ID: 7939162

Larvae of Simulium damnosum complex collected from rivers draining Tukuyu onchocerciasis focus were chromosomally examined. Of the 970 larvae analysed, 910 were identified as Kiwira form, a newly described cytotype found in all S. damnosum larval habitats in the Tukuyu area, while 51 were classified as a new subpopulation, tentatively named as Kasyabone form. The F1 larval progeny obtained from wild caught human biting S. damnosum and reared in the laboratory were chromosomally examined. 509 F1 larvae from 70 females blood fed on human volunteers were identified as Kiwira form. As the main human-biting member of the complex in the Tukuyu area, and because some of the wild caught females had developing filarial larvae indistinguishable from those of Onchocerca volvulus, Kiwira form is thus incriminated as the local vector of onchocerciasis. These observations are discussed with respect to previous literature.

Differential Modulation of Murine Cellular Immune Responses by Salivary Gland Extract of Aedes Aegypti

The American Journal of Tropical Medicine and Hygiene. Nov, 1994  |  Pubmed ID: 7985763

The ability of salivary gland extract (SGE) of Aedes aegypti to modulate cellular immune responses was investigated in a mouse model. Cytokine production was induced in naive and antigen-primed murine (BALB/c) spleen cells in vitro by stimulation with the T cell mitogen concanavalin A or the T cell-dependent antigen ovalbumin (OVA), respectively. Inclusion of Ae. aegypti SGE in in vitro culture with naive cells caused significant suppression of the cytokines interleukin-2 (IL-2) and interferon gamma in culture supernatants, while levels of other cytokines (IL-4 and IL-5) were unaffected by SGE. In contrast, SGE did not affect cytokine production by antigen-activated cells derived from OVA-primed mice. To determine whether SGE could inhibit the responsiveness of cells to exogenous cytokine stimuli, optimized quantities of lymphocyte growth factor cytokines IL-2 and IL-4 were added to SGE-treated spleen cells and the degree of cellular proliferation was determined. Cellular proliferation in response to IL-2 was markedly suppressed by prior exposure of cells to SGE, while the proliferative response to IL-4 was also affected by SGE but to a lesser extent. These results confirm that mosquito SGE can modulate host immune responses, and suggest that in Ae. aegypti modulation is directed primarily against cytokines associated with type 1 lymphocyte responses. The mode of immunomodulation and the possible relevance of these results to vector-borne disease research are discussed.

Onchocerca Lienalis: a Comparison of Microfilarial Loss in Simulium Jenningsi and Simulium Vittatum

Experimental Parasitology. Sep, 1994  |  Pubmed ID: 8056080

Salivary Apyrase in African and New World Vectors of Plasmodium Species and Its Relationship to Malaria Transmission

The American Journal of Tropical Medicine and Hygiene. Feb, 1994  |  Pubmed ID: 8116818

The salivary gland activities of apyrase, an enzyme that prevents platelet aggregation by eliminating ADP, were compared among five members of the Anopheles gambiae species complex and An. albimanus. Within the An. gambiae group, An. quadriannulatus exhibited the lowest amount of enzyme activity at all pH levels measured. Apyrase activity could be separated into three groups at pH 7.5 and 8.0. The two most anthropophilic species (An. gambiae and An. arabiensis) exhibited higher activity at pH 9.0. Anopheles merus and An. melas, both saltwater taxa, and An. albimanus, a New World species, exhibited peak apyrase activity at pH 8.0. When the effects of divalent cations (Ca++, Mg++) on enzyme activity were compared at pH 8.5, apyrase activity in the presence of Mg++ could be separated into three levels. Anopheles gambiae and An. quadriannulatus exhibited reduced activity in the presence of Mg++. Anopheles arabiensis, An. merus, and An. melas displayed the highest relative levels of activity. Anopheles albimanus, with a Mg:Ca ratio of 0.80, was most similar to An. arabiensis. These biochemical differences suggest that different isoenzymes of apyrase have developed within the genus Anopheles.

Vasodilative Activity in Black Fly Salivary Glands

The American Journal of Tropical Medicine and Hygiene. Feb, 1994  |  Pubmed ID: 8116819

Salivary gland extracts of several Simulium spp. were shown to contain vasodilative activity as measured by the rapid and persistent induction of erythema in response to intradermal injection into rabbit skin. Total salivary gland activities were approximately equal for S. vittatum, S. metallicum, S. bivittatum, and S. argus (titers of 0.03-0.02 pairs of gland). Total gland activity in the highly anthropophilic species S. ochraceum, however, was an order of magnitude greater, with erythema produced by as little as 0.002 pairs of glands. Tests for physical stability of the activities from two species (S. vittatum and S. ochraceum) indicated that the vasodilators were proteinaceous and heat stable. A two-step, reversed-phase high-performance liquid chromatography (HPLC) procedure was developed that isolated both activities with similar elution patterns. Homogeneity of the purified protein from S. vittatum was confirmed by capillary gel electrophoresis. Electrospray ionization mass spectroscopy of the S. vittatum protein detected a mass of 15,351 daltons. Similarity in elution times of the proteins from a TSK HPLC column predict some structural similarities between the S. vittatum and S. ochraceum vasodilator proteins.

Onchocerca Lienalis: Rapid Clearance of Microfilariae Within the Black Fly, Simulium Vittatum

Experimental Parasitology. Mar, 1994  |  Pubmed ID: 8119373

A rapid decrease of about a third of the number of Onchocerca lienalis microfilariae (mf) parenterally inoculated into Simulium vittatum black flies occurred within 5 hr postinoculation (pi). The change of mf counts over time was modeled by a segmented linear regression. During 2 hr pi the slope was -3.5 mf/hr (P < or = 0.001) and between 2 and 24 hr pi the slope was -0.1 mf/hr. Although significantly different from the former slope (P < 0.001), the latter was not significantly different from zero (P > 0.2). The decrease could not be attributed to excretion of mf. Microfilariae (especially those heat-killed prior to inoculation) in intermediate stages of destruction were observed in flies dissected 5 hr pi but not immediately after injection. No short- or long-term (24 hr pi) effects of the injection procedure alone on mf survival were evident. A constant proportion of mf was eliminated regardless of dose within a range of 5 to 100 mf/fly during 24 hr pi. However, a second injection of 50 mf/fly 2.5 hr following an injection of the same dose resulted in a significantly lower proportion of mf eliminated. These results suggest that the availability of an active factor(s) in the fly was reduced 2.5 hr after the first inoculation. The change in the availability of this factor(s) may partly explain the change in clearance rate occurring 2 hr pi. Soluble factor(s), rather than a sequence of cellular responses, seems to be involved in the rapid clearance because it occurred in freshly killed flies at a similar rate to that observed in live flies. The hypothesis that mf differ in their innate susceptibility to rapid clearance was rejected as mf that were recovered 2 hr pi and reinoculated into other flies were eliminated faster than unexposed controls. It is concluded that the rapid clearance of mf represents an as yet undescribed immune response to macroparasites of the fly host.

Expression of CD33, CD38, and HLA-DR on CD34+ Human Fetal Liver Progenitors with a High Proliferative Potential

Blood. Jun, 1994  |  Pubmed ID: 7514903

High proliferative-potential colony-forming cells (HPP-CFC) have been identified in the bone marrow of mice and adult humans, and have been characterized as a compartment of primitive progenitors possibly including stem cells. In this report we describe the human fetal liver (FL) as a source of HPP-CFC. These FL HPP-CFC develop in clonal cultures in the presence of granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-3 (IL-3) within 3 to 4 weeks. The median frequency of HPP-CFC in FL tissues between 16 and 21 weeks of gestational age was 1 in 3,000 total FL cells. After 4 weeks of growth, FL HPP-CFC grew to a median colony size of 8.3 x 10(4) cells/colony. Using cell-sorting techniques FL HPP-CFC were shown to be predominantly contained in the CD34+ CD33+ CD38- fraction of FL cells. FL HPP-CFC were heterogeneous for HLA-DR expression, and no differences in proliferative capacities were observed between HLA-DR+ and HLA-DR- HPP-CFC. The CD34+ CD33-HLA-DR- CD38- population, previously suggested to contain stem cells, was observed to be very rare in the FL, representing approximately 1 in 1.7 x 10(5) light-density FL cells and containing almost no CFC. Therefore, it is possible that stem cells are contained in the CD33+ fraction of FL cells. Phenotypic characterization of CD34+ CD33+ CD38- lin -LDFL cells showed that these cells are also CD13+, predominantly Thy-1+, CD45RA-, CD45RO-, CD71-, and heterogenoeous for c-kit expression. These data suggest that FL HPP-CFC represent a heterogeneous compartment of primitive myeloid progenitors that may include stem cells.

Differential Regulation of Gonadotropin Synthesis and Release in Ovariectomized Ewes After Treatment with a Luteinizing Hormone-releasing Hormone Antagonist

Biology of Reproduction. Oct, 1994  |  Pubmed ID: 7529575

Our working hypothesis was that synthesis and release of LH, but not FSH, were solely dependent on LHRH. Twenty ovariectomized (OVX) ewes were randomly assigned to one of five treatments (n = 4 per group). Ewes were administered a low (10 micrograms/kg) or high (100 micrograms/kg) dose of LHRH antagonist (LHRH-Ant) at 24-h intervals for 3 or 6 days. Control ewes received vehicle (5% mannitol) at 24-h intervals for 6 days. Blood samples were collected every 15 min for 4 h before LHRH-Ant or vehicle and every 2 h during the period of treatment to determine concentrations of LH and FSH. Twenty-four hours after the last treatment with LHRH-Ant or vehicle, anterior pituitaries were collected and divided in half along the midsagittal plane; the number of receptors for LHRH, pituitary content of LH and FSH, and relative amounts of mRNA for alpha, LH beta, and FSH beta subunits were determined. Concentrations of LH in serum decreased (p < 0.05) from 25.4 +/- 4.3 ng/ml before LHRH-Ant to less than 0.5 ng/ml within 4 h after the first treatment of LHRH-Ant and remained low (< 0.5 ng/ml) throughout the study. Serum concentrations of FSH declined gradually during the 3- or 6-day period of treatment with LHRH-Ant, from 37.3 +/- 2.4 and 26.5 +/- 4.8 ng/ml to 19.9 +/- 1.8 and 13.7 +/- 2.1 ng/ml, respectively. The magnitude of decline in serum concentrations of LH and FSH did not differ among ewes treated with low or high doses of LHRH-Ant.(ABSTRACT TRUNCATED AT 250 WORDS)

Increasing Concentrations of 17 Beta-estradiol Has Differential Effects on Secretion of Luteinizing Hormone and Follicle-stimulating Hormone and Amounts of MRNA for Gonadotropin Subunits During the Follicular Phase of the Bovine Estrous Cycle

Biology of Reproduction. Feb, 1995  |  Pubmed ID: 7536049

The hypothesis tested was that 17 beta-estradiol (E2) would increase amounts of mRNA for alpha, LH beta, and FSH beta subunits during the follicular phase of the estrous cycle prior to the preovulatory surge of gonadotropins in cows. On Day 16 (Day 0 = estrus) of the estrous cycle, all cows were treated with prostaglandin F2 alpha (PGF2 alpha). Cows served as intact controls (CONT, n = 4) were ovariectomized (OVX, n = 5), or were ovariectomized and administered E2 (OVXE, n = 6) in increasing doses starting at the time of treatment with PGF2 alpha. Cows were bled for 6 h before and for 40 h after PGF2 alpha treatment to characterize pulsatile secretion of LH and FSH. Forty hours after PGF2 alpha treatment, pituitaries were collected for evaluation of amounts of mRNA for alpha, LH beta, and FSH beta subunits. Amplitude of LH pulses was greater (p < 0.05) in cows from the OVXE than from the CONT group. Concentrations of FSH were greater in cows from both the OVXE and OVX (p < 0.01) groups than from the CONT group. Amounts of mRNA for alpha and FSH beta subunits were greater (p < 0.01) in pituitaries of cows from the OVX than from the CONT or OVXE groups. Amounts of mRNA for LH beta subunit in pituitaries of cows from the OVX group tended to be greater (p < 0.08) than from the CONT group. Cows in the OVXE group tended (p < 0.08) to have greater amounts of mRNA for FSH beta subunit than did CONT cows.(ABSTRACT TRUNCATED AT 250 WORDS)

Salivary Apyrase in New World Blackflies (Diptera: Simuliidae) and Its Relationship to Onchocerciasis Vector Status

Medical and Veterinary Entomology. Jul, 1995  |  Pubmed ID: 7548952

Salivary gland apyrase is believed to be critical to blood-feeding in arthropod vectors. This enzyme was measured in six New World blackflies representing three taxonomic pairs of non-vectors and vectors of Onchocerca volvulus. In Simulium (Psilopelmia) ochraceum, a highly anthropophilic vector in Mexico and Guatemala, apyrase exhibited maximum activity between pH 8.0 and 9.0, mean 39.8 +/- 4.7 milliUnits/pair of gland equivalents (mU), and was enhanced when ATP was used as a substrate. In the zoophilic non-vector Simulium (Psilopelmia) bivittatum maximum activity was significantly less (5.1 +/- 0.7 mU) under all conditions examined. Preference for ADP or ATP as substrate was a function of the pH of the reaction for this species. Apyrase activity in Simulium (Simulium) metallicum Bellardi (29.5 +/- 11.5 mU), a zoophilic secondary vector in Mexico and Guatemala, resembled that of S. (Ps.) ochraceum (24.8 +/- 13.7 mU at pH 8.5) with ADP as substrate, but showed reduced activity with ATP. Both these Central American vectors had higher apyrase activity than found in Simulium (Notolepria) exiguum, a vector of O. volvulus in Ecuador and Colombia. However, maximum apyrase activity, measured at pH 8.0 with ADP as substrate, was greater in S. (N.) exiguum (10.9 +/- 0.6 mU) than in Simulium (Notolepria) gonzalezi (5.9 +/- 1.9 mU), a non-vector species widespread in Central America. Therefore, for the consubgeneric species pairs examined, a positive association was detected between higher concentrations of apyrase activity and their vector status for O.volvulus.

Differential Regulation of Transforming Growth Factor Beta-1 Gene Expression by Glucocorticoids in Human T and Glial Cells

Journal of Immunology (Baltimore, Md. : 1950). Nov, 1995  |  Pubmed ID: 7594600

The inflammatory process in the brain requires bidirectional interaction of the immune and nervous systems. Evidently, astrocytic glial cells play an important role in facilitating this communication by releasing immunomodulators and cytokines. Expression of transforming growth factor beta-1 (TGF beta-1), a potent inhibitor of T cell function and glial cell proliferation, is highly regulated in T cells and is believed to be an important component in the molecular interaction between the immune and nervous systems. Comparative analysis of TGF beta-1 gene expression in human T and glial cells by Northern hybridization and S1 nuclease protection assay showed that dexamethasone (DM) caused a significant decrease in the basal and PMA-induced levels of TGF beta-1 mRNA in glial cells but not in T cells. This reduction correlated with a lower level of TGF beta-1 protein production. Transient transfection assay using deletion constructs of the 5' TGF beta-1 gene promoter-containing sequences between -453 and +11 bp identified a region spanning -160 to -60 bp as a potential sequence responsive to regulation by DM in T cells, whereas in glial cells, the overall transcriptional activity of the 5' TGF beta-1 promoter was reduced after DM treatment, but promoter activity within each construct remained constant in response to DM. Thus, a DM-responsive region could not be identified within the TGF beta-1 promoter in glial cells. These findings suggest that TGF beta-1 gene expression is differentially regulated by distinct regulatory elements in T and glial cells, and that extracellular stimulators, including glucocorticoids, can utilize the TGF beta-1-regulatory pathway to affect the functions of neural and immune cells.

Infiltrating Intramuscular Lipoma of the Paraspinal Muscles

The Annals of Otology, Rhinology, and Laryngology. Jul, 1995  |  Pubmed ID: 7598373

Developmental Status, Gender, Age, and Self-reported Decision-making Influences on Students' Risky and Preventive Health Behaviors

Health Education Quarterly. May, 1995  |  Pubmed ID: 7622391

This study used decision-making theory to analyze the developmental changes associated with children's and adolescents' health behavior. High school and elementary school children completed surveys concerning (1) the extent to which they engage in a variety of preventive and risky health behaviors, and (2) influence sources used in decision making concerning the enactment of these behaviors. Multiple regression analysis revealed that the sources of influence children and adolescents report considering in making health-related decisions change developmentally and as a function of gender. Moreover, within and across age, children's sources of influence with respect to health decision making are dependent on the health domains being considered. The findings are discussed in relation to decision-making theory and the implications for the content and timing of health education initiatives for adolescents.

Analysis of Migration Success of Onchocera Lienalis Microfilariae in the Haemocoel of Simulium Vittatum

Journal of Helminthology. Mar, 1995  |  Pubmed ID: 7622790

Migration success (i.e. the proportion of worms that reach the thorax) of Onchocerca lienalis microfilariae (mf) in the haemocoel of Simulium vittatum was studied by inoculating mf into the posterior abdomen, and recording their distribution in the blackfly body at predetermined time points. Mf arrive into the thorax by active locomotion rather than by drifting in haemolymph currents. Migration into the thorax was completed by 12 h post inoculation (pi) but was not continuous throughout this period. Migration proceeded in two phases; the first occurred 0-2 h pi and the second at 6-12 h pi. Overall, migration success 12-24 h pi was only 36%, indicating that a substantial number of mf failed to reach the thorax, either because they were eliminated by the fly's defensive response or because they remained in the abdomen. Migration success was density independent. Mf that arrive into the thorax within 2 h pi did not differ in their migration potential from mf that remained in the abdomen at this time. In flies where more mf migrated successfully there was lower mf loss, indicating that migration success was linked to mf loss. Moreover, the proportion of mf in the thorax was not correlated with mf loss, suggesting that mf loss affected the number of mf that migrated successfully, rather than the reverse causal relationship.

The Detection of Human Papillomavirus Deoxyribonucleic Acid in Intraepithelial, in Situ, Verrucous and Invasive Carcinoma of the Penis

The Journal of Urology. Sep, 1995  |  Pubmed ID: 7637047

We study the prevalence of human papillomavirus deoxyribonucleic acid (DNA) in squamous cell carcinoma and control tissue of the penis.

The Extended Abbé Flap

The Laryngoscope. Sep, 1995  |  Pubmed ID: 7666736

Large upper lip defects that include the surrounding aesthetic subunits of the midface are difficult to reconstruct. Abbé flaps have been a popular method of dealing with small upper lip defects but, as classically described, they are insufficient for larger defects. We performed cadaver injections to evaluate the vascular territory supplied by the inferior labial artery with particular attention to the submental area. Extended Abbé flaps were then designed and used in combined upper lip and midfacial reconstruction. Three cases and guidelines for the use of the extended Abbé flap are presented.

Occurrence of Lutzomyia Anthophora (Diptera: Psychodidae) in Arizona

Journal of Medical Entomology. Sep, 1995  |  Pubmed ID: 7473634

Males and females of Lutzomyia anthophora Addis were collected by vacuum aspiration from woodrat, Neotoma albigula Hartley, and rock squirrel, Citellus variegatus Bailey, nests along Arivaca Creek in Pima County, Arizona. Additional flies were collected from the same location using CDC miniature light traps supplemented with CO2. These collections extend the recorded geographic distribution of this vector of Leishmania mexicana Biagi westward by approximately 724 km and place Lu. anthophora in a Sonoran desert habitat.

Effects of 17 Beta-estradiol on Distribution of Pituitary Isoforms of Luteinizing Hormone and Follicle-stimulating Hormone During the Follicular Phase of the Bovine Estrous Cycle

Biology of Reproduction. Feb, 1995  |  Pubmed ID: 7711199

The objective of this study was to examine the influence of 17 beta-estradiol (E2) on distribution of LH and FSH isoforms during the follicular phase of the bovine estrous cycle prior to the preovulatory surges of LH and FSH. On Day 16 of the estrous cycle (Day 0 = estrus), intact controls (CONT; n = 4) were treated with prostaglandin F2 alpha (PGF2 alpha) to induce luteal regression and initiation of the follicular phase. Other cows were also treated with PGF2 alpha and either ovariectomized (OVX; n = 5) or ovariectomized and given E2 implants (OVXE; n = 6) to mimic the pattern of increasing E2 concentrations during the follicular phase of the estrous cycle. Pituitaries were collected 40 h after treatment with PGF 2 alpha or ovariectomy (0 h). Aliquots of pituitary extracts were chromatofocused on pH 10.5-4.0 gradients. The LH resolved into thirteen isoforms (designated A-L and S, beginning with the most basic form) while FSH resolved into nine isoforms (designated I-IX, beginning with the most basic form). The percentage of LH as isoform F (elution pH = 9.32 +/- 0.01) was greater (p < 0.05) in the OVX group (48.5%) than in the OVXE group (45.0%). LH isoforms I (elution pH = 6.98 +/- 0.01) and J (elution pH = 6.48 +/- 0.01) were more abundant (p < 0.05) in cows from the OVXE (2.3 and 5.8%, respectively) than the OVX group (1.4 and 3.7%, respectively). Distribution of LH isoforms in cows from the three groups did not differ (p > 0.10).(ABSTRACT TRUNCATED AT 250 WORDS)

Melengestrol Acetate at Greater Doses Than Typically Used for Estrous Synchrony in Bovine Females Does Not Mimic Endogenous Progesterone in Regulation of Secretion of Luteinizing Hormone and 17 Beta-estradiol

Biology of Reproduction. Feb, 1995  |  Pubmed ID: 7711214

Our working hypothesis was that doses of melengestrol acetate (MGA) greater than those typically administered in estrous synchrony regimens would regulate secretion of LH and 17 beta-estradiol (E2) as endogenous progesterone (P4) does during the midluteal phase of the estrous cycle. We also hypothesized that endogenous P4 from the CL would interact with MGA to further decrease the frequency of LH pulses and E2. Cows on Day 5 of their estrous cycle (Day 0 = estrus) were randomly assigned to an untreated control group (CONT, n = 5) or to one of six MGA treatment groups (n = 5 per group): 1) MGA administered orally each day via a gelatin capsule at a dose of 0.5 mg MGA/cow with the CL present (0.5CIL); 2) 0.5 mg MGA/cow daily in the absence of CL (0.5NO); 3) 1.0 mg MGA with CL present (1.0CL); 4) 1.0 mg MGA without CL (1.0NO); 5) 1.5 mg MGA with CL present (1.5CL); 6) 1.5 mg without CL (1.5NO). MGA was administered for 10 days (Day 5 = initiation of treatment). To regress CL, cows assigned to groups without CL received injections of prostaglandin F 2 alpha (PGF 2 alpha; 25 mg) on Days 6 and 7 of their estrous cycle. All cows were administered PGF2 alpha at the end of the 10-day treatment period. During the treatment period, daily blood samples were collected to determine concentrations of E2. Serial blood samples were collected at 15-min intervals for 24 h on Days 8, 11, and 14 to determine pattern of LH secretion.(ABSTRACT TRUNCATED AT 250 WORDS)

Dosage of the Synthetic Progestin, Norgestomet, Influences Luteinizing Hormone Pulse Frequency and Endogenous Secretion of 17 Beta-estradiol in Heifers

Biology of Reproduction. Feb, 1995  |  Pubmed ID: 7711215

The objective of this study was to determine whether there were doses at which the synthetic progestin, norgestomet, could mimic midluteal phase concentrations of progesterone in regulating the secretion of LH and 17 beta-estradiol in bovine females. Heifers were randomly assigned to one of five groups to receive: 1) one (1Norg, n = 5), 2) two (2Norg, n = 5), 3) four (4Norg, n = 5), or 4) eight (8Norg, n = 5) norgestomet implants or to serve as untreated control heifers (control, n = 5). On Day 7 (Day 0 = behavioral estrus), implants containing norgestomet were inserted, and they remained in place for 10 days. All heifers implanted with norgestomet were treated with 25 mg prostaglandin F2 alpha (PGF2 alpha) on Days 7 and 8 to lyse the CL. Controls were treated with 25 mg PGF2 alpha at the time norgestomet implants were removed from heifers of the other treatment groups. Blood samples were collected every 15 min for 24 h on Days 10 and 16 to determine the frequency of LH pulses. Beginning 24 h after removal of implants, samples of blood were collected at 4-h intervals for 96 h to determine the time of the preovulatory surge of LH. Daily blood samples were collected from Day 2 to Day 48 to determine concentrations of progesterone, and samples collected between Days 2 and 17 were used to determine concentrations of 17 beta-estradiol. Ultrasonography was performed daily from Day 2 until Day 23 to evaluate ovarian follicular development.(ABSTRACT TRUNCATED AT 250 WORDS)

The Volume of Prostate Cancer in the Biopsy Specimen Cannot Reliably Predict the Quantity of Cancer in the Radical Prostatectomy Specimen on an Individual Basis

The Journal of Urology. May, 1995  |  Pubmed ID: 7714976

Previous studies suggest that prostate cancer with a volume of 0.5 ml. or less and a Gleason score of less than 7 may be clinically insignificant and may be managed with watchful waiting. A proposed method of determining the volume of cancer in the prostate gland has been the grade and volume of cancer present in the transrectal needle biopsy specimen. Volume of cancer in the biopsy specimen as a predictor of volume of cancer in the prostate gland was studied in 130 men who underwent radical retropubic prostatectomy for adenocarcinoma. Of the men 46 (35%) had clinical stage T1c (nonpalpable) disease, while 84 (65%) had clinical stage T2 (palpable) disease. Each radical prostatectomy specimen was whole-mounted and step-sectioned for accurate cancer volume determination. Three parameters for measuring volume of cancer in the biopsy specimen (percentage of biopsy cores involved, millimeters of cancer per biopsy core and percentage of cancer in the biopsy specimen) were determined and compared by Spearman rank correlation analysis. The percentage of cancer in the biopsy specimen was marginally better than the percentage of cores involved and the millimeters of cancer per biopsy core as a predictor of cancer volume in the radical prostatectomy specimen. While regression analysis revealed a direct correlation between the volume of cancer in the biopsy and radical prostatectomy specimens (r = 0.51), there was significant variability in prostate cancer volume for a given percentage of cancer in the biopsy specimen since the standard error of the estimate was 6.1 ml. Of the 13 patients with 5% or less cancer volume and a Gleason score of less than 7 in the biopsy specimen 1 (8%) had a cancer smaller than 0.5 ml. in volume in the radical prostatectomy specimen. Therefore, the risk of removing clinically insignificant prostate cancer, even when the biopsy parameter indicates low volume disease, is less than 10%. Overall, only 3 study patients (2.3%) had a prostate cancer volume of less than 0.5 ml. With 97.7% of the men having a clinically significant cancer by a volume criterion, it is apparent that the majority of clinically insignificant prostate cancers remained undetected and untreated. Currently, transrectal needle biopsy does not provide adequate information for differentiating between clinically insignificant and life threatening prostate cancer on an individual basis.

Chemical Guidance of Onchocerca Lienalis Microfilariae to the Thorax of Simulium Vittatum

Parasitology. Apr, 1995  |  Pubmed ID: 7724240

The behavioural responses of Onchocerca lienalis microfilariae (mf) to tissue factors of the surrogate black fly host, Simulium vittatum, were studied using a novel in vitro bioassay. Mf accumulated towards thoracic tissues to a density 4 times higher than towards abdominal tissues, despite the larger surface area and volume of abdominal tissues. Mf migrated toward thoracic tissues regardless of whether or not contact with thoracic tissues was possible. Therefore, mf directed themselves toward the thorax rather than arresting their movement after they make contact with thoracic tissues. Chemical cue(s) provided a principal guidance for mf to locate thoracic tissues. Mf lost their ability to differentiate thoracic and abdominal tissues following addition of thoracic attractant(s) to excised abdomens and reversed their differential response when excised thoraces were depleted of chemical cue(s). Mf did not respond to salivary gland product, but to other thoracic factor(s). Intact thorax that was connected to 1-2 abdominal segments attracted considerably less mf than excised thorax. However, intact thorax attracted more mf than excised abdomen. Abdominal tissue size did not affect thorax attractiveness. Involvement of a large molecular weight protein(s) was suggested by the high attractiveness of the 100 kDa Centricon concentrator retentate and complete precipitation of attractant(s) by ethanol.

Role of Specific Response Elements of the C-fos Promoter and Involvement of Intermediate Transcription Factor(s) in the Induction of Sertoli Cell Differentiation (transferrin Promoter Activation) by the Testicular Paracrine Factor PModS

Endocrinology. Jul, 1995  |  Pubmed ID: 7789331

A mesenchymal-epithelial cell interaction exists in the testis between the Sertoli cells that form the seminiferous tubule and the mesenchymal-derived peritubular myoid cells that surround the tubule. Analysis of the mesenchymal-epithelial interactions between these cells revealed the local production of a mesenchymal factor, PModS. PModS modulates the differentiated functions of Sertoli cells in vitro, including stimulation of the iron-binding protein transferrin (Tf). Previous results have indicated that PModS-induced Tf gene expression involves the activation of immediate early genes. One of the immediate early genes was identified as c-fos. The importance of c-fos was demonstrated in the current study when a c-fos antisense oligonucleotide was found to inhibit the ability of PModS to induce the expression of a Tf promoter-chloramphenicol acetyltransferase (CAT) construct. The regulation of c-fos by PModS was investigated with various CAT constructs containing segments of the c-fos promoter, such as the serum response element (SRE), sis-inducible element (SIE), cAMP response element (CRE), and phorbol ester/TPA response element (TRE), transfected into cultured Sertoli cells. PModS has no effect on cAMP response element-CAT or TRE-CAT, suggesting that PModS does not act through stimulation of cAMP and protein kinase C pathways. PModS was found to activate the c-fos SRE-CAT construct and the SIE-CAT construct. A construct containing both SIE and SRE was stimulated to the same degree as either element alone. Gel mobility shift assays using nuclear extracts from PModS-stimulated Sertoli cells and a radiolabeled SRE oligonucleotide resulted in retarded mobility of a DNA-protein complex. A gel shift with a SRE oligonucleotide containing an ETS domain resulted in a unique shift only detected in PModS stimulated cells. PModS also promoted a gel shift with the SIE that is adjacent to the SRE on the c-fos promoter. The data imply that PModS can activate the c-fos promoter through the SRE and SIE. PModS caused a labeled activating protein 1 (AP1) oligonucleotide to form a DNA-protein complex, indicating activation of the c-fos gene and binding of the c-fos/jun complex. To study the downstream regulation of Sertoli cell differentiation, Tf gene expression was examined. CAT constructs containing deletion mutants of a 3-kilobase (kb) mouse Tf promoter were used. When transfected into Sertoli cells the 581-base pair Tf minimal promoter had only a slight response to PModS, but was activated by FSH. The 2.6-kb Tf promoter construct responded to PModS.(ABSTRACT TRUNCATED AT 400 WORDS)

Promoting Prosthetics in the Latino Community

The Journal of Biocommunication. 1995  |  Pubmed ID: 8904482

This article describes an effective approach to informing the Latino community about prosthetics. Unlike English, little information on this subject is available in Spanish. The process of obtaining, fabricating, and wearing a prosthesis was interwoven into the teleplay "Milagros." The story concept, video production, and the Latino population's cultural characteristics are discussed. The audience welcomed the opportunity to share the information with others.

Novel Anticoagulant from Salivary Glands of Simulium Vittatum (Diptera: Simuliidae) Inhibits Activity of Coagulation Factor V

Journal of Medical Entomology. Jan, 1996  |  Pubmed ID: 8906925

Anticoagulant activity was detected in fractions of a reversed phase-high-performance liquid chromatography (RP-HPLC) of salivary gland lysate from Simulium vittatum Zetterstedt. Using a plasma recalcification time assay, these fractions did not inhibit factor Xa or thrombin. HPLC-purified fractions showing the anticoagulant property were pooled and examined using the activated partial thromboplastin time test conducted on normal plasma and plasmas deficient in factors V, VIII, IX, XI, and XII. The anticoagulant prolonged the clotting time of all the plasmas, except plasma deficient in factor V. The detection of antifactor V activity, together with other anticoagulants reported from Simulium spp. indicates a feeding strategy that targets enzymes in the terminal portion of the coagulation cascade.

Development of Persistent Ovarian Follicles During Synchronization of Estrus Influences the Superovulatory Response to FSH Treatment in Cattle

Theriogenology. Feb, 1996  |  Pubmed ID: 16727822

The synchronization of estrus with synthetic progestins or progesterone (P(4)) results in the development of a large, persistent ovarian follicle. The objectives of the present study were to determine if development of a persistent ovarian follicle during synchronization of estrus suppresses recruitment of additional follicles during FSH treatment. On Day 5 of the estrous cycle (estrus = Day 0), beef cows were treated with 0.5 or 2.0 P(4) releasing intravaginal devices (PRIDs) for 8 d (Experiment 1, n = 20), 5 or 2 d (Experiment 2, n = 44) before initiation of FSH treatment. Prostaglandin F(2alpha) (25 mg) was administered on Days 5 and 6. Superovulation was induced with 24 mg of recombinant bovine FSH (rbFSH, Experiment 1) or 28 mg of FSH-P (Experiment 2) over a 3- or 4-d period, respectively. The PRIDs were removed concurrently with the 5th injection of rbFSH or FSH-P. There was a treatment-by-day interaction (P < 0.001) for the concentration of 17beta-estradiol in cows treated for 8, 5 or 2 d before FSH treatment. In Experiment 1, FSH treatment initiated 8 d after insertion of a 0.5 PRID did not affect the number of CL (6.9 +/- 1.4 vs 6.7 +/- 1.6), ova/embryos (3.7 +/-1.3 vs 3.0 +/- 1.3) and transferable embryos (2.4 +/- 0.9 vs 3.0 +/- 0.9) compared with that of the 2.0 PRIDs. In Experiment 2, FSH treatment initiated 5 d after insertion of a 0.5 PRID decreased the number of CL (4.0 +/- 0.5 vs 8.3 +/- 0.8; P < 0.001), ova/embryos (3.0 +/- 0.6 vs 5.9 +/- 1.2; P < 0.03) and transferable embryos (2.3 +/- 0.6 vs 5.1 +/- 1.0; P < 0.03) compared with that of a 2.0 PRID, respectively. Initiation of FSH treatment 2 d after insertion of a 0.5 PRID compared with a 2.0 PRID had no affect on the number of CL (8.0 +/- 2.1 vs 8.7 +/- 1.2), total ova (4.8 +/- 1.4 vs 6.9 +/- 1.4) and transferable embryos (2.9 +/- 1.2 vs 6.1 +/- 1.7). In conclusion, treatment with low doses of P(4) (0.5 PRID) for 5 d but not for 2 or 8 d before initiation of FSH treatment results in the development of a dominant ovarian follicle, which reduces recruitment of ovarian follicles, and the number of CL, total ova and transferable embryos.

Lessons from Low Enrollment in ACE Inhibitor Cough Study

The Annals of Pharmacotherapy. Apr, 1996  |  Pubmed ID: 8729900

The Effects of Macrophages on the Survival of Random Skin Flaps in Swine

The Laryngoscope. Sep, 1996  |  Pubmed ID: 8822712

Tissue macrophages play a critical role in neovascularization by releasing angiogenic cytokines. Macrophages normally arrive into a wound bed 48 to 96 hours following an injury. Introducing macrophages into a wound bed at the time of closure would theoretically stimulate neovascularization in the traumatized tissue prior to what is normally observed. The ability to promote early angiogenesis could be an important factor in the survival of an extended skin flap. By taking advantage of advanced cell-sorting techniques, the authors developed the first study to evaluate the effect of placing a purified autologous macrophage population into an extended skin flap. We created 72 dorsally based random skin flaps in Yorkshire pigs; 48 of these wounds received autologous macrophages while 24 flaps served as controls. The macrophages were obtained by utilizing monoclonal antibodies in conjunction with flow cytometry. The skin flaps were evaluated on postoperative day 6 for their viability. Analysis of the data showed no statistically significant difference between the control and treatment flaps. There was, however, a trend of increased survival for flaps treated with macrophages. This is the first study to investigate using a purified population of cells to improve the survival of random skin flaps.

Changing Dose of Progesterone Results in Sudden Changes in Frequency of Luteinizing Hormone Pulses and Secretion of 17 Beta-estradiol in Bovine Females

Biology of Reproduction. Mar, 1996  |  Pubmed ID: 8835375

The aim of the present study was to elucidate the time course according to which changes in circulating concentrations of progesterone influence pulsatile secretion of LH and secretion of 17 beta-estradiol. Our working hypothesis was that changing the dose of progesterone would result in changes in frequency of LH pulses and secretion of 17 beta-estradiol within 72 h. Five days after behavioral estrus, thirty-three cows were randomly assigned to one of five groups: 1) control, no treatment (CONT, n = 5); 2) treatment with two progesterone-releasing intravaginal devices (PRIDs) for 11 days (2PRID, 5-6 ng/ml plasma progesterone, n = 7); 3) treatment with a 0.5 PRID for 11 days (0.5PRID, 1-2 ng/ml plasma progesterone, n = 7); 4) treatment with 2 PRIDs for 8 days followed by treatment with a 0.5 PRID for 3 days (2-0.5PRID, n = 7); and 5) treatment with a 0.5 PRID for 8 days followed by treatment with 2 PRIDs for 3 days (0.5-2PRID, n = 7). Cows subject to PRID treatments received injections of prostaglandin F2 alpha on Days 1 and 2 (Day 0 = day of initiation of PRID treatments, fifth day of the estrous cycle in CONT cows) to lyse the existing corpus luteum. Cows were bled for 12 h at 15-min intervals on Day 7.5 of the treatment period (twelfth day of the estrous cycle in CONT cows). The dose of progesterone was changed on Day 8 in cows that were assigned to the 2-0.5PRID and 0.5-2PRID groups, and blood collections continued an additional 72 h to characterize profiles of circulating concentrations of LH and 17 beta-estradiol. Cows treated with a 0.5 PRID had a greater (p < 0.05) number of LH pulses and higher (p < 0.05) concentrations of 17 beta-estradiol throughout the entire blood collection period than cows in the 2PRID and CONT groups. An increase in the number of LH pulses was detected within 6 h after the change from the high to the low dose of progesterone (2-0.5PRID), and frequency of LH pulses was similar to that of cows in the 0.5PRID group for the remainder of the period of blood collection. LH pulse frequency declined within 6 h after the shift from the low to the high dose of progesterone (0.5-2PRID) and was similar to that of cows in the 2PRID group by 12 h after the dose was changed. Within 6 h after the dose of progesterone was changed, circulating concentrations of 17 beta-estradiol increased (p < 0.05) in cows shifted from the high to low dose (2-0.5PRID) and declined (p < 0.05) after the dose of progesterone was changed from low to high (0.5-2PRID). We conclude that changing the circulating concentrations of progesterone concurrently affects frequency of pulsatile LH release and secretion of 17 beta-estradiol within 6-24 h.

Transcriptional Regulation of Sertoli Cell Differentiation by Follicle-stimulating Hormone at the Level of the C-fos and Transferrin Promoters

Biology of Reproduction. Mar, 1996  |  Pubmed ID: 8835393

One of the primary endocrine hormones that influence the onset of Sertoli cell differentiation at puberty and help maintain differentiation in the adult testis is FSH. FSH can modulate the majority of Sertoli cell differentiated functions, including stimulation of the iron-binding protein transferrin. Previous studies have shown that FSH alters the levels of cAMP and the immediate early gene c-fos. The current study was designed to investigate the transcriptional regulation of Sertoli cell differentiation by examining the actions of FSH on the promoter of the immediate early gene c-fos and the promoter of the downstream differentiated function gene transferrin. The regulation of c-fos by FSH was investigated with various chloramphenicol acetyltransferase (CAT) constructs containing segments of the c-fos promoter, such as the serum response element (SRE), cAMP response element (CRE), and AP1/phorbol ester/TPA response element (TRE), that were transfected into cultured Sertoli cells. Observations indicate that FSH can stimulate all three response elements, as well as a whole c-fos promoter construct. Interestingly, FSH was found to have a more dramatic effect on the SRE-CAT than a cAMP analog, suggesting a difference in the actions of the two agents. Gel mobility shift assays were performed to confirm the reporter gene results. Nuclear extracts of FSH-stimulated Sertoli cells caused a labeled AP1 oligonucleotide to form a DNA/protein complex (i.e., gel shift), indicating activation of the c-fos gene and binding of the c-fos/jun complex. Nuclear extracts from both FSH- and cAMP-stimulated Sertoli cells promoted similar gel shifts with SRE and CRE oligonucleotides. This observation supports the reporter gene data in indicating that FSH can influence both the SRE and CRE. A gel mobility shift assay was also performed with an oligonucleotide containing the 5'-flanking ETS domain of the SRE (ETS-SRE) that allows the formation of a ternary complex. FSH-stimulated Sertoli cell nuclear extracts were found to promote a unique ETS-SRE gel shift not present in cAMP-stimulated cells. The observations imply that FSH actions on the SRE are in part distinct from the actions of cAMP. Transferrin gene expression was examined to study the downstream regulation of Sertoli cell differentiation. CAT constructs containing deletion mutants of a 3-kb mouse transferrin promoter were used. When transfected into Sertoli cells, the 581-bp transferrin minimal promoter, previously shown to contain a CRE, had a significant response to cAMP and FSH. The 1.6-, 2.6-, and 3-kg transferrin promoter constructs also responded to FSH and cAMP to the same extent as, or to a lesser extent than, the 581-bp minimal promoter. Interestingly, the actions of FSH on the 581-bp minimal transferrin promoter were more dramatic than those of cAMP. The importance of FSH-induced c-fos in the regulation of transferrin expression was demonstrated in the current study when a c-fos antisense oligonucleotide was found to partially inhibit (50%) the ability of FSH to induce the expression of a transferrin promoter (CAT) construct. Therefore, FSH appears to act through multiple transcriptional activation pathways. The first involves cAMP and the CRE at both early-event genes (e.g., c-fos) and downstream genes (e.g., transferrin). It is likely that other pathways involve alternate signal transduction events (e.g., calcium mobilization) and promoter response elements (e.g., SRE). These multiple pathways may act in a compensatory manner to assure the ability of FSH to influence Sertoli cell differentiation and/or in a synergistic manner to amplify FSH actions.

Comparison of Circulating Concentrations of Reproductive Hormones in Boars of Lines Selected for Size of Testes or Number of Ovulations and Embryonal Survival to Concentrations in Respective Control Lines

Journal of Animal Science. Aug, 1996  |  Pubmed ID: 8856445

The objectives of this study were to determine whether circulating concentrations of genadotropins and gonadal hormones of boars were altered as a result of selection of pigs for size of testes or for embryonal survival and(or) number of ovulations. Included in Exp. 1 and 2 were boars with the greatest estimated paired weight of testes (TS) and boars from a control (C) line. Concentrations of FSH were similar (P > .10) in boars from the TS and C lines. In Exp. 3, 4, and 5, circulating concentrations of FSH and 17 beta-estradiol (E2) were evaluated in neonates, during pubertal development, and in mature boars of lines selected for an index of number of ovulations and embryonal survival (I), and data were compared to those for boars from a respective C line. Concentrations of E2 were not different in boars from the I line and those from the C line during the early neonatal period but were greater (P < .05) in boars of the C line than in those from the I line during pubertal development. Concentrations of FSH were greater (P < .05) in mature boars from the I line than in those from the C line. In summary, selection for size of testes did not influence circulating concentrations of FSH in mature boars. The secretory pattern of E2 in boars before puberty changed as a result of selection for embryonal survival and number of ovulations in females of the I line, and the different patterns of circulating E2 early in life may result in enhanced circulating concentrations of FSH in adult boars of the I line compared with boars of the C line.

Soluble Factors Secreted by Activated T-lymphocytes Modulate the Transcription of the Immunosuppressive Cytokine TGF-beta 2 in Glial Cells

Journal of Cellular Biochemistry. Sep, 1996  |  Pubmed ID: 8872606

Coordination of the immune response to injury or disease in the brain is postulated to involve bi-directional discourse between the immune system and the central nervous system. This cross communication involves soluble mediators, including various growth factors, cytokines, and neuropeptides. In this report, we demonstrate that the supernatant from activated T-lymphocytes is able to induce the transcription of a potent cytokine, TGF-beta 2 in glial cells. The activating stimulus invokes signaling mechanisms distinct from known kinase or protease pathways. Activation of TGF-beta 2 transcription correlates with the loss of binding activity for an 80 kDA glial labile repressor protein, GLRP, to a responsive region within the TFG-beta 2 promoter. Although GLRP shares some characteristics with the inducible transcription factor AP-1, it appears to be distinct from known AP-1 family members. These data along with previous observations demonstrating the potent immunosuppressive activity of TGF-beta 2, support a model for a feedback mechanism between the activated T-lymphocytes and astrocytes via TGF-beta 2 to regulate the immune response.

Detection of Human Papillomavirus DNA in Primary Squamous Cell Carcinoma of the Male Urethra

Urology. Oct, 1996  |  Pubmed ID: 8886059

The prevalence of human papillomavirus deoxyribonucleic acid (DNA) in primary squamous cell carcinoma of the male urethra and corresponding control tissue was studied.

Molecular Phylogeny and Typing of Blackflies (Diptera: Simuliidae) That Serve As Vectors of Human or Bovine Onchocerciasis

Medical and Veterinary Entomology. Jul, 1996  |  Pubmed ID: 8887332

A subregion of the mitochondrial large subunit (16s) rRNA gene was amplified by polymerase chain reaction (PCR) from nine species of blackflies (Diptera: Simuliidae) which serve as natural or experimental vectors of human or bovine Onchocerca parasites. PCR products from each species of blackfly were tested by directed heteroduplex analysis (DHDA), and their genotypes established according to diagnostic banding patterns of the heteroduplex products. Three alleles of mitochondrial 16s rRNA were found to exist in members of the Simulium (Ewardsellum) damnosum sensu lato complex from West Africa, and two alleles were found in the Neotropical Simulium (Psilopelmia) ochraceum Walker complex and the Simulium (Simulium) metallicum Bellardi complex. Different single alleles were detected in Austrosimulium bancrofti, in English S.(S)noelleri and in two North American laboratory vectors: Simulium (Psilozia) vittatum Zetterstedt and S.(S.)decorum Walker. Phylogenetic analysis of 16s sequences indicated that blackflies from West Africa and the Americas formed distinct clades. Neotropical onchocerciasis vectors were found to be more closely related to Nearctic and Palaearctic non-vector Simulium species than to the African vectors of onchocerciasis.

Gonadotropin Secretion and Development of Ovarian Follicles During Oestrous Cycles in Heifers Treated with Luteinizing Hormone Releasing Hormone Antagonist

Animal Reproduction Science. Dec, 1997  |  Pubmed ID: 9505103

The hypothesis tested was that reduced LHRH stimulation of the anterior pituitary would lead to attenuated development of ovarian follicles as a result of reduced gonadotropin secretion during oestrous cycles of cattle. Twenty heifers were randomly assigned to be treated ( n = 5/treatment) with an antagonist to LHRH (LHRH-Ant) 1) from Day 2 to 7 (Day 0 = behavioural oestrus), 2) Day 7 to 12, 3) Day 12 to 17, 4) or serve as untreated control animals. LHRH-Ant suppressed LH pulses of heifers in all treatment groups from treatment initiation through Day 17 as compared with untreated control heifers [Peters et al., 1994. Luteinizing hormone has a role in development of fully functional corpora lutea (CL) but is not required to maintain CL function in heifers. Biol. Reprod., 51 (1994) 1248-1254]. Circulating concentration of FSH from Day 8 to 10 of the oestrous cycle did not increase in heifers treated with LHRH-Ant from Day 2 to 7 or Day 7 to 12; however, there was increased (P < 0.05) FSH from Day 8 to 10 of the oestrous cycle in heifers treated with LHRH-Ant from Day 12 to 17 and control heifers. Compared with control heifers, heifers treated with LHRH-Ant from the Day 2 to 7 had suppressed (P < 0.05) size and persistence of the first and second dominant ovarian follicles. Heifers treated with LHRH-Ant from Day 7 to 12 had suppressed size (P < 0.05 and tended (P < 0.10) to have a shorter persistence of the second dominant ovarian follicle compared with control heifers. Heifers treated with LHRH-Ant from Day 12 to 17 had a similar (P > 0.10) size and persistence of dominant ovarian follicles but had reduced (P < 0.10) numbers of large follicles compared with control heifers. Heifers treated with LHRH-Ant from Day 2 to 7 had lower (P < 0.01) concentrations of 17 beta-oestradiol during the treatment period and tended (P < 0.10) to have lower concentrations of 17 beta-oestradiol from Day 7 to 12 of the oestrous cycle compared with control heifers. Heifers treated with LHRH-Ant from Day 7 to 12 or Day 12 to 17 had similar (P > 0.10) circulating LH concentrations of l7 beta-oestradiol compared with control heifers. Reduced LHRH stimulation of the pituitary from Day 2 to 12 of the oestrous cycle and the resulting modulation in circulating LH and FSH led to suppressed ovarian follicular development and oestradiol secretion. After Day 12 of the oestrous cycle, reduced LHRH stimulation of the anterior pituitary did not lead to altered ovarian follicular development to the extent as reduced LHRH stimulation before Day 12 although pulsatile release of LH was similarly suppressed by treatment with the LHRH-Ant.

Role of Basic-helix-loop-helix Transcription Factors in Sertoli Cell Differentiation: Identification of an E-box Response Element in the Transferrin Promoter

Endocrinology. Feb, 1997  |  Pubmed ID: 9003001

Sertoli cells are critical for testicular function and maintenance of the spermatogenic process. The induction of Sertoli cell differentiation in the embryo promotes testicular development and male sex determination. The progression of Sertoli cell differentiation during puberty promotes the onset of spermatogenesis. The maintenance of optimal Sertoli cell differentiation in the adult is required for spermatogenesis to proceed. The current study was designed to investigate the transcriptional regulation of Sertoli cell differentiation through the analysis of a previously identified marker of differentiation, transferrin gene expression. Sertoli cells produce transferrin to transport iron to developing spermatogenic cells sequestered within the blood-testis barrier. The transferrin promoter was characterized and found to contain two critical response elements, designated Sertoli element 1 (SE1) and Sertoli element 2 (SE2). Through sequence analysis, SE2 was found to contain an E-box response element, which has been shown to respond to basic-helix-loop-helix (bHLH) transcription factors. The bHLH proteins are a class of transcription factors associated with the induction and progression of cell differentiation. bHLH proteins dimerize through the conserved helix-loop-helix region and bind DNA through the basic region. Nuclear extracts from Sertoli cells were found to cause an E-box gel shift when the cells were stimulated to differentiate in culture, but not under basal conditions. The SE2 gel shift of Sertoli nuclear extracts was competed with excess unlabeled SE2 or E-box DNA fragments. Several Sertoli nuclear proteins associate with the SE2 gel shifts, including 70-, 42-, and 25-kDa proteins. Therefore, the critical SE2 element in the transferrin promoter is an E-box element capable of binding bHLH transcription factors. The ubiquitously expressed E12 bHLH protein dimerizes with numerous cell-specific bHLH factors. A Western blot analysis demonstrated that E12 was present in Sertoli cell nuclear extracts and associated with the SE2 gel shift. A ligand blot of Sertoli cell nuclear extracts with radiolabeled E12 had apparent bHLH proteins when the cells were stimulated to differentiate. The E-box sequence in the SE2 fragment of the transferrin promoter was CATCTG and was similar in gel shifts to the consensus E-box elements (CANNTG) previously characterized. A bHLH inhibitory factor (Id) competed and inhibited formation of the Sertoli cell nuclear extract E-box gel shift. To extend this observation, Id protein was overexpressed in cultured Sertoli cells. A transferrin promoter chloramphenicol acetyltransferase construct was used to monitor Sertoli cell function. The presence of Id suppressed the activation of the promoter induced by Sertoli differentiation factors. Therefore, the inhibition of Sertoli bHLH factors by Id suppressed Sertoli cell differentiated function, as measured by transferrin expression. An E-box-chloramphenicol acetyltransferase construct was also found to be active in Sertoli cells when cells were induced to differentiate. Screening the computerized nucleotide data bases demonstrated that putative E-box response elements are present in the promoters of a large number of Sertoli cell differentiated genes. In summary, a critical E-box response element has been identified in the transferrin promoter that can be activated by bHLH factors (e.g. E12) present in Sertoli cells. Inhibition of Sertoli bHLH factors by Id suppresses Sertoli cell differentiated function (i.e. transferrin expression), suggesting that bHLH transcription factors may be important in regulating Sertoli cell differentiated functions.

Cellular Hemolymph Response of Simulium Vittatum (Diptera:Simuliidae) to Intrathoracic Injection of Onchocerca Lienalis (Filarioidea:Onchocercidae) Microfilariae

Journal of Medical Entomology. Jan, 1997  |  Pubmed ID: 9086712

Hemolymph cellular changes in Simulium vittatum Zetterstedt in response to intrathoracic injection with Onchocerca lienalis Stiles were characterized by increased numbers of tissue fragments that contained cells embedded within a noncellular matrix. Cell numbers within the matrix fragments increased both for sham and microfilariae-injected files, indicating a blastogenic response to injection alone. Morphological characteristics of fixed, Giemsa-stained cells within these tissue fragments were most similar to those previously described for prohemocytes. The total population of freely circulating hemocytes collected 24 h after injection also responded to injection alone. Differential cell counts showed a complex pattern of changes that was influenced strongly by increased numbers of prohemocytes at 24 h in microfilariae-injected flies. Fat body fragments collected in hemocoel perfusates at 24 h were fewer when flies were maintained at 27 degrees C than at 21 degrees C. More fat body fragments were collected from microfilariae-injected flies than from control and sham-injected flies held at 27 degrees C. Injection of 1.25-5 micrograms of lipopolysaccharide per fly did not elicit similar hemolymph-associated matrix tissue and fat body changes, indicating that S. vittatum response to microfilaria infection and bacteria infection are likely to involve different mechanisms.

Black Fly (Diptera:Simuliidae) Salivary Secretions: Importance in Vector Competence and Disease

Journal of Medical Entomology. Mar, 1997  |  Pubmed ID: 9103750

When blood-feeding, black flies introduce secretions into the feeding lesion that act in a coordinated manner on the 3 arms of the vertebrate hemostatic system (platelet aggregation, coagulation, and vasoconstriction). Apyrase activity inhibits platelet aggregation and is ubiquitous in the saliva of black flies, although activity per gland varies by species and has a positive association with anthropophagy. Anticoagulants target components in the final common pathway of the coagulation cascade, including factors V, Xa, and II (thrombin). The antithrombin salivary protein may exert a redundant effect by inhibiting the role of thrombin in platelet aggregation. Antithrombin presence and activity also varies among black fly species, and exhibits a positive correlation with zoophagy. Vasodilation of capillaries to increase blood supply to the feeding wound appears to be an important requirement for Simulium spp., because substantial erythema-inducing activity, has been demonstrated in salivary glands of all New World species examined. Salivary glands of Simulium ochraceum (Walker), a highly anthropophilic vector of Onchocerca volvulus (Leuckhart), contain greater vasodilator activity than several other species, including S. metallicum Bellardi, a secondary zoophagic vector of human onchocerciasis. Simulium vittatum Zetterstedt saliva affects immune cell responses and cytokine production. The ability of the saliva to modulate components of the host immune system provides an opportunity for enhancing transmission of pathogens during bloodfeeding. Thus, the likely possibility that effective pathogen transmission relies on vector saliva may complement present efforts aimed at target epitopes of O. volvulus or identify additional molecules to be investigated as part of a "river blindness" vaccine cocktail. Components in saliva also may enhance the transmission of other microbial agents either by a cofeeding process similar to that observed in ixodid ticks or through rupture of the labrum during escape of Onchocerca infective stage larvae. In a few instances, saliva of some Simulium spp. also has been associated with extensive tissue and organ pathology, including hemorrhagic shock and death. Pathologic signs associated with this syndrome indicate an enhanced antihemostatic activity in saliva.

Vector Competence of Select Black Fly Species for Vesicular Stomatitis Virus (New Jersey Serotype)

The American Journal of Tropical Medicine and Hygiene. Jul, 1997  |  Pubmed ID: 9242316

Black flies collected from southern Arizona were evaluated for their vector competence to the Oaxaca and Camp Verde isolates of vesicular stomatitis virus (New Jersey serotype) (VSV-NJ). The Camp Verde isolate is the index isolate of the 1982-1983 VSV-NJ epizootic that infected humans and livestock in 14 western states. Previous experiments have shown that colonized Simulium vittatum females are competent laboratory vectors of both virus isolates. However, under controlled laboratory conditions, Simulium bivittatum and S. longithallum were found to be incompetent vectors of both virus isolates. After oral infections, the Oaxaca isolate replicated in 35% and 38% of S. bivittatum and S. longithallum, respectively, but did not disseminate to the salivary glands. Thus, virus was not detected in the saliva of either black fly species with either VSV-NJ isolate, indicating the presence of a midgut barrier. Simulium notatum was found to be a competent laboratory vector of both virus isolates. Infectious virions were detected in the saliva of 23% and 26% of S. notatum infected orally with the Oaxaca and Camp Verde VSV-NJ isolates, respectively. This study suggests that the black fly identified as S. bivittatum was probably not involved in virus dissemination during the 1982-1983 epizootic in the western United States. Because the geographic distribution of S. notatum is not known, its involvement in that epizootic remains obscure.

The Fenfluramine/phentermine Combination for Weight Loss

The Nurse Practitioner. Aug, 1997  |  Pubmed ID: 9279853

Melatonin

American Family Physician. Oct, 1997  |  Pubmed ID: 9337764

Melatonin, a hormone produced by the pineal gland, appears to help regulate the sleep-wake cycle. With further study and clinical experience, it may become an accepted therapy for insomnia. Although melatonin preparations are available without prescription in health food stores and pharmacies, their potency, purity, safety and effectiveness cannot be assured. Until large clinical trials provide further information about melatonin's efficacy, adverse effects, drug interactions and effects on various disease states, melatonin products should be used with the understanding that many questions about their safety remain unanswered.

Cytochrome P450: New Nomenclature and Clinical Implications

American Family Physician. Jan, 1998  |  Pubmed ID: 9447218

Many drug interactions are a result of inhibition or induction of cytochrome P450 enzymes (CYP450). The CYP3A subfamily is involved in many clinically significant drug interactions, including those involving nonsedating antihistamines and cisapride, that may result in cardiac dysrhythmias. CYP3A4 and CYP1A2 enzymes are involved in drug interactions involving theophylline. CYP2D6 is responsible for the metabolism of many psychotherapeutic agents. The protease inhibitors, which are used to treat patients infected with the human immunodeficiency virus, are metabolized by the CYP450 enzymes and consequently interact with a multitude of other medications. By understanding the unique functions and characteristics of these enzymes, physicians may better anticipate and manage drug interactions and may predict or explain an individual's response to a particular therapeutic regimen.

Steroid Use in Rhinoplasty: an Objective Assessment of Postoperative Edema

Ear, Nose, & Throat Journal. Jan, 1998  |  Pubmed ID: 9473831

The objective of this study was to measure the effect of a single, preoperative 10 mg dose of dexamethasone on postoperative edema associated with rhinoplasty. This was a randomized, double-blind prospective study conducted in a military academic tertiary referral center. Twenty men, aged 18 to 45 years, were enrolled in the study over 28 months. All 20 men underwent rhinoplasty with osteotomy. Preoperative magnetic resonance imaging scans were obtained on the morning of surgery and postoperative scans were obtained within 48 hours. Postoperative edema was quantified as the difference in soft tissue thickness (mm) between the pre- and postoperative scans. Contrary to our expectations, the rhinoplasty patients who received dexamethasone had increased postoperative edema (p < 0.02) when compared to patients not receiving dexamethasone. This is the first objective, double-blind study that shows an increase in postoperative edema after rhinoplasty with a single preoperative dose of dexamethasone.

Use and Abuse of Flunitrazepam

The Annals of Pharmacotherapy. Jan, 1998  |  Pubmed ID: 9475831

Flunitrazepam is not available in the US, and it is presently illegal to import it. Flunitrazepam has no therapeutic advantage over benzodiazepines presently marketed in the US. Its quick onset of sedation, amnesic properties, and additive effects with alcohol have led to its reputation as a party drug, club drug, or date rape drug. Several measures have been undertaken to curb its illicit use. It is unclear whether flunitrazepam poses a greater public health risk than other benzodiazepines.

Developmental and Hormonal Regulation of Transforming Growth Factor-beta1 (TGFbeta1), -2, and -3 Gene Expression in Isolated Prostatic Epithelial and Stromal Cells: Epidermal Growth Factor and TGFbeta Interactions

Endocrinology. Mar, 1998  |  Pubmed ID: 9492075

Growth factors are postulated to mediate stromal-epithelial interactions in the prostate to maintain normal tissue physiology. Transforming growth factor-beta (TGFbeta) has been shown to influence the prostate and probably mediate stromal-epithelial interactions. TGFbeta1 messenger RNA (mRNA) expression is stimulated after castration and can be suppressed by in vivo treatment with androgens. The hypothesis tested is that TGFbeta is regulated not only by androgen, but also by a network of locally produced growth factors that influence prostatic growth and differentiation. Epithelial and stromal cells from 20-day-old rat ventral prostate were isolated and used to test this hypothesis. The expression of mRNA for TGFbeta1, -2, and -3 was analyzed by a quantitative RT-PCR procedure. Observations from this assay demonstrate that both epithelial and stromal cells express the mRNA for TGFbeta1, -2, and -3. TGFbeta1 mRNA expression was constant during development of the prostate. TGFbeta2 mRNA expression was elevated at birth, then declined and elevated again at 100 days of age. TGFbeta3 mRNA expression was high during puberty and young adult ages then declined at 100 days of age. TGFbeta2 and TGFbeta3 expression are inversely related during prostate development. After castration of 60-day-old rats, both TGFbeta1 and TGFbeta2 mRNA were enhanced. Interestingly, TGFbeta3 mRNA was significantly suppressed after castration. Epidermal growth factor (EGF) stimulated TGFbeta1 mRNA expression in stromal cells (6-fold increase), whereas keratinocyte growth factor stimulated TGFbeta2 mRNA in epithelial cells. TGFbeta inhibited both testosterone- and EGF-stimulated prostatic stromal and epithelial cell growth. EGF and TGFbeta also inhibited prostatic ductal morphogenesis and growth in organ culture. Immunocytochemical localization of TGFbeta in 20-day-old prostate demonstrated predominately stromal localization of the protein. These results indicate that the isoforms of TGFbeta2 and TGFbeta3 are differentially regulated during prostate development, suggesting distinct regulatory mechanisms. Testosterone did not affect TGFbeta expression in cultured prostatic cells. These observations suggest that the in vivo effects of castration on TGFbetas are regulated indirectly through a complex network of growth factors, not simply by direct androgen depletion. The ability of EGF to inhibit prostatic ductal morphogenesis and growth in organ culture is postulated to be in part mediated by the increase in TGFbeta1 expression. In summary, a network of growth factor-mediated stromal-epithelial interactions is needed to maintain prostate growth and development. TGFbeta is postulated to have an important role in this process.

George Brownlee Craig, Jr. July 8, 1930-December 21, 1995

Biographical Memoirs. National Academy of Sciences (U.S.). 1998  |  Pubmed ID: 11623757

Macrophage Inflammatory Protein-1beta Induces Migration and Activation of Human Thymocytes

Blood. Apr, 1998  |  Pubmed ID: 9531601

The CC chemokine macrophage inflammatory protein 1beta (MIP-1beta), has been shown to be a chemoattractant preferentially activating CD4(+) CD45RA+ T lymphocytes. Further analysis of chemokine action on lymphocytic cells has shown the potent migration-promoting capacity of MIP-1beta on human thymocytes. The responding cells were the CD4(+) and CD8(+) single-positive (SP), as well as the CD4(+) CD8(+) double-positive (DP) populations, with little if any migratory activity on the double-negative (DN) population. The activation of thymocytes by MIP-1beta appeared to be a direct, receptor-mediated event as evidenced by the rapid mobilization of intracellular calcium, increase in proteins phosphorylated on tyrosine, and activation of the mitogen-activated protein kinase (MAPK) pathway. Radioligand binding analyses showed specific and displaceable binding of MIP-1beta to thymocytes with a Kd of approximately 1 nmol/L, a profile that was comparable with MIP-1beta binding to CCR-5-transfected NIH 3T3 cells. In addition, CCR-5 mRNA was detected in total thymocyte populations indicating that activation of thymocytes by MIP-1beta may occur through binding to CCR-5. Further dissection of the subpopulations showed that only the DP and CD8(+) SP populations expressed CCR-5 and expression data on these two populations was confirmed using anti-CCR-5 monoclonal antibody. These data may be suggestive of a role for MIP-1beta in human thymocyte activation, and show a potential route for HIV infectivity in the developing immune system.

Comparison of Black Fly Species (Diptera: Simuliidae) on an Amerindian Reservation with a High Prevalence of Fogo Selvagem to Neighboring Disease-free Sites in the State of Mato Grosso Do Sul, Brazil. The Cooperative Group on Fogo Selvagem Research

Journal of Medical Entomology. Mar, 1998  |  Pubmed ID: 9538571

Fogo selvagem is an autoimmune blistering skin disease that principally occurs among rural Brazilians living in geographically clumped disease foci. Exposure to hematophagous black flies possibly is related to the cause of the disease. We compared the occurrence, proportions, and richness of simuliid species immatures and the biting activity of adult females within a recently discovered, high prevalence focus of fogo selvagem, the Limão Verde Terena Reservation, to that of neighboring regions with no reported cases of fogo selvagem. Nine black fly species were collected from 12 stream sites during 5 trips to the fogo selvagem focus. The species showed longitudinal (upstream-downstream) trends in occurrence, proportions, and richness, and the abundance of simuliid immatures was greater at downstream sites. The most prevalent species at the focus, Simulium nigrimanum (Macquart), dominated the stream sites with highly abundant simuliid assemblages, and was the most common black fly in human bait collections. This species was absent or in very low numbers in neighboring valleys and villages that did not have cases of fogo selvagem.

Analyses of CDNA and Recombinant Protein for a Potent Vasoactive Protein in Saliva of a Blood-feeding Black Fly, Simulium Vittatum

The Journal of Experimental Biology. May, 1998  |  Pubmed ID: 9556538

A cDNA was cloned from the salivary glands of a blood-feeding black fly Simulium vittatum. The encoded protein has been given the name Simulium vittatum erythema protein or SVEP, because of its ability to increase blood perfusion in skin capillaries, resulting in the well-characterized erythema of black fly bites. The full-length cDNA contains 548 base pairs which encode 152 amino acid residues of the nascent protein. Post-translational processing produces a mature, secreted protein of 133 residues with a molecular mass of 15.4 kDa. Recombinant SVEP (rSVEP) was produced in a baculovirus expression system and purified by a one-step reversed-phase HPLC procedure. Analyses of physical properties and biological potency demonstrated fidelity of rSVEP to the native protein. Recombinant SVEP relaxed rabbit aorta preparations when preconstricted with 2 micromol l-1 phenylephrine or 25 mmol l-1 K+ but not with 60 mmol l-1 K+. Further, the rSVEP-induced relaxation response of phenylephrine-constricted aorta was inhibited by glibenclamide (10 micromol l-1), suggesting that at least part of its action to relax smooth muscle may result from the opening of ATP-dependent K+ channels. SVEP is a novel salivary-gland-derived vasoactive protein that may be essential for blood feeding by black flies and could potentially enhance transmission of filarial parasites.

Kava: an Herbal Sedative

The Nurse Practitioner. Jun, 1998  |  Pubmed ID: 9656257

Blood-feeding Strategy of Haematobia Irritans (Diptera: Muscidae)

Journal of Medical Entomology. Jul, 1998  |  Pubmed ID: 9701950

The economic impact on livestock production by Haematobia irritans (L.) is estimated to approach $1 billion per year in North America. However, there is little information regarding the blood-feeding strategy used by these insects. Information presented here shows that horn fly saliva interferes with the normal coagulation response as measured by the recalcification time assay. The relative anticoagulant activity on a per-gland basis was more than or equal to that reported for Simulium vittatum Zetterstedt, a common hematophagous black fly that also feeds on cattle. However, unlike S. vittatum, H. irritans salivary factors do not inhibit platelet aggregation using apyrase and have no detectable vasodilative activity. In this regard, the horn fly is strikingly different from blood-feeding species in the lower Diptera and shows a much more limited repertoire of antihemostatic factors.

Doxorubicin Dosage Guidelines in a Patient with Hyperbilirubinemia of Gilbert's Syndrome

The Annals of Pharmacotherapy. Oct, 1998  |  Pubmed ID: 9793595

To reconcile dosage modification guidelines for doxorubicin in a patient with hyperbilirubinemia of Gilbert's syndrome (GS).

The Peptide Recognized by HLA-A68.2-restricted, Squamous Cell Carcinoma of the Lung-specific Cytotoxic T Lymphocytes is Derived from a Mutated Elongation Factor 2 Gene

Cancer Research. Nov, 1998  |  Pubmed ID: 9823325

The identification of naturally processed tumor peptides that can stimulate a tumor-specific, CTL response is crucial to the development of a vaccine-based, immunotherapeutic approach to cancer treatment. One type of cancer in which a tumor-specific, CTL response has been observed is squamous cell carcinoma of the lung. In the system investigated here, the tumor-specific CTLs are HLA-A68.2 restricted. Immunoaffinity chromatography was used to isolate the HLA-A68.2 molecules from the tumor cell line, and peptide was eluted with acid from the HLA-A68.2 molecules and subjected to three rounds of separation by reversed phase-high performance liquid chromatography (RP-HPLC). To determine which fractions contained the peptide recognized by the tumor-specific CTLs, an aliquot of each RP-HPLC fraction was added to the autologous, B-lymphoblastoid cell line, and the cells were then tested as targets for tumor-specific CTLs. After the third round of RP-HPLC, mass spectrometry was used to sequence individual peptide candidates, and a peptide with a m/z of 497 was identified as the active peptide. Collision-activated dissociation of m/z 497 allowed identification of the peptide sequence as ETVSEQSNV. With the exception of a single amino acid difference (glutamic acid versus glutamine as the sixth position in the peptide), this peptide is identical to residues 581 to 589 of elongation factor 2. The PCR was used to amplify the elongation factor 2 gene in both the tumor cells and the autologous B cell line, and DNA sequencing of the products revealed the presence of a heterozygous mutation in the tumor cells that accounts for the difference between the two peptide sequences. Although a similar analysis did not reveal the presence of the mutation in three additional lung cell carcinomas, this does not rule out the possibility that a survey of a larger population of tumor cells would reveal the presence of the mutation at a low frequency. These results demonstrate the utility of this approach for identifying tumor-specific antigens that are the targets of a CTL response.

Concentrations of Gonadotropins, Estradiol and Progesterone in Sows Selected on an Index of Ovulation Rate and Embryo Survival

Animal Reproduction Science. Dec, 1998  |  Pubmed ID: 9877063

The objective of this study was to determine concentrations of follicle stimulating hormone (FSH), luteinizing hormone (LH), progesterone (P4) and 17beta-estradiol (E2) in sows from a line selected on an index which emphasized ovulation rate (Select) and from a control line. A further classification of the sows in each line was made according to the estimated number of ovulations during an estrous cycle. Sows in the Select line were ranked into a high (HI) or low group (LI) when their estimated number of ovulations were 25 or more and 14 to 15, respectively. Sows of the control line were classified into groups as high (HC) or low (LC) when the estimated values for ovulation rate were 14-15 and 8-9 ovulations, respectively. Blood samples were collected every 12 h during a complete estrous cycle and samples were analyzed for concentrations of FSH and LH. Samples collected every 24 h were assayed for P4 and E2. Mean concentrations of FSH, LH, P4 and E2 did not differ (P > 0.10) between lines or between HI and LI or HC and LC groups. Selection of pigs for ovulation rate and embryonal survival did not affect concentrations of FSH, LH, P4 and E2 in sows during the estrous cycle.

Molecular-Beam Electric-Resonance Optothermal Spectroscopy Study of the Rotational Spectrum of the Less Stable Conformer of Methyl Vinyl Ether

Journal of Molecular Spectroscopy. Jan, 1999  |  Pubmed ID: 9878495

The pure rotational spectrum of the less stable conformer of methyl vinyl ether has been measured in an electric-resonance optothermal spectrometer. Analysis of the microwave spectrum shows that the less stable conformer is effectively planar with a low barrier between two gauche forms of the conformer. The rotational constants for the high-energy conformer, obtained from a least-squares fit to a threefold barrier internal rotation Hamiltonian are A = 39 192.490(26) MHz, B = 4527.5496(39) MHz, and C = 4181.2146(43) MHz. The threefold barrier to internal rotation is determined to be V3 = 427.516(71) cm-1. The dipole moment for the conformer has been measured using the Autler-Townes splitting of states in a strong, resonant microwave field. The dipole moment is µtot = 1.9(2) D [µa = 1.3(1) D, µb = 1.4(1) D]. The effectively planar structure of the conformer and the magnitude of the dipole moment are in good agreement with previous ab initio calculations. The experimentally determined threefold barrier to methyl rotation of the present study also agrees well with the value calculated from ab initio methods, 515 cm-1. Copyright 1999 Academic Press.

Glucosamine Sulfate Use in Osteoarthritis

American Journal of Health-system Pharmacy : AJHP : Official Journal of the American Society of Health-System Pharmacists. Feb, 1999  |  Pubmed ID: 10030516

Herbal Remedies: Adverse Effects and Drug Interactions

American Family Physician. Mar, 1999  |  Pubmed ID: 10088878

A growing number of Americans are using herbal products for preventive and therapeutic purposes. The manufacturers of these products are not required to submit proof of safety and efficacy to the U.S. Food and Drug Administration before marketing. For this reason, the adverse effects and drug interactions associated with herbal remedies are largely unknown. Ginkgo biloba extract, advertised as improving cognitive functioning, has been reported to cause spontaneous bleeding, and it may interact with anticoagulants and antiplatelet agents. St. John's wort, promoted as a treatment for depression, may have monoamine oxidase-inhibiting effects or may cause increased levels of serotonin, dopamine and norepinephrine. Although St. John's wort probably does not interact with foods that contain tyramine, it should not be used with prescription antidepressants. Ephedrine-containing herbal products have been associated with adverse cardiovascular events, seizures and even death. Ginseng, widely used for its purported physical and mental effects, is generally well tolerated, but it has been implicated as a cause of decreased response to warfarin. Physicians must be alert for adverse effects and drug interactions associated with herbal remedies, and they should ask all patients about the use of these products.

The Septum in Rhinoplasty

Otolaryngologic Clinics of North America. Feb, 1999  |  Pubmed ID: 10196436

Recognition and correction of septal abnormalities in rhinoplastic surgery has been a constant evolution aided by the development of an in depth anatomic understanding of the nose and the refinement of techniques based on the pertinent anatomy. Whether the deformity presents a functional, aesthetic, or combined problem, the authors prefer a single stage technique that separates the structural components of the nose, isolating the deformities present, and then reconstructing the components to effect a desirable result in terms of airway and appearance. Although no two nasal surgeries are identical, there are characteristic deformities that are noted to be generally more problematic. We briefly review normal septal anatomy as it pertains to the septorhinoplasty operation and then discuss our approach to specific septal variations that we have found to have a significant impact with regard to achieving satisfactory functional and aesthetic results.

Action of Retinoids on Embryonic and Early Postnatal Testis Development

Endocrinology. May, 1999  |  Pubmed ID: 10218988

The current study investigates the hypothesis that retinoids have a role in embryonic testis development. The action of retinoids on testis development and the expression of retinoic acid receptors (RAR alpha, RAR beta, RAR gamma) were examined. In embryonic day 13 (E13; plug date = E0) testis organ cultures an RAR-selective agonist and all-trans retinoic acid completely inhibited seminiferous cord formation. In contrast, an RAR alpha-selective antagonist had no effect. RT-PCR demonstrated that RAR alpha messenger RNA (mRNA) was expressed at all developmental time points evaluated, which included embryonic day 14 (E14) through postnatal day 30 (P30). Expression of RAR beta mRNA was present at E15 through P2, whereas RAR gamma mRNA was expressed at E18 through P2. Cellular localization of receptors by immunohistochemistry indicated that RAR alpha was localized to the interstitium at E18 and to the seminiferous cords by P0. RAR beta and RAR gamma were detected in both interstitium and cords at E16 and by E18 were mainly expressed in the cords. At P0 RAR beta and RAR gamma were localized to the germ cell populations. To examine retinoid actions, the growth of P0 testis cultures were investigated. Interestingly, retinol and retinoic acid did not inhibit growth of P0 testis cultures but did inhibit the action of growth stimulators. Retinoic acid inhibited FSH, EGF, and 10% calf serum stimulated growth in P0 testis cultures. The hypothesis tested was that the inhibitory effects of retinoids on P0 testis growth may be mediated through the growth inhibitor, transforming growth factor-beta (TGF beta). The action of retinoids on TGF beta mRNA expression was examined in P0 testis cultures. Retinoic acid stimulated TGFbeta3 mRNA expression within 24 h and increased expression of TGFbeta1 and TGFbeta2 after 72 h. Retinol increased expression of TGFbeta1 and TGFbeta2 but not TGFbeta3 after 72 h of treatment. These observations indicate that retinoic acid can influence seminiferous cord formation and testis growth. The inhibitory actions of retinoids may in part be mediated through increased expression of TGFbeta isoforms.

Effects of Activated Macrophages and Fibroblast Growth Factor on Random Skin Flap Survival in Swine

The Laryngoscope. Jul, 1999  |  Pubmed ID: 10401860

To examine the effect of application of activated autologous macrophages and basic fibroblast growth factor (FGF) on random skin flap survival in swine.

Age-related Kinetic Changes in Normal Pediatrics

Journal of Pediatric Orthopedics. Jul-Aug, 1999  |  Pubmed ID: 10412996

Kinetic data have become an important adjunct to kinematic and electromyography data in the interpretation of gait data and in the clinical decision making for children with pathologic gait patterns. A normative database is essential for comparison with the patterns of walking in children with gait abnormalities. Gait analyses of 23 able-bodied children (ages 4-10 years) were compared with those of five able-bodied adults. The patterns and amplitudes of the normal able-bodied children's kinetics showed five significant differences from those of the adults: (a) diminished hip-abduction moment, (b) diminished plantar-flexion moment, (c) diminished A2 power generation, (d) diminished knee-extensor moment, and (e) pattern of knee-power data. The data indicated a progression toward the adult normals because differences were more significant in the youngest group (4- to 5-year-olds) than in the older groups (6- to 7- and 8- to 10-year-olds).

The Continuing Search for Proper Perspective: Whose Reasonableness Should Be at Issue in a Prescription Product Design Defect Analysis?

Seton Hall Law Review. 1999  |  Pubmed ID: 10848104

This Article is based on a presentation given at Seton Hall University School of Law's Seventh Annual Health Law Symposium on February 12, 1999.

Expression and Action of Transforming Growth Factor Beta (TGFbeta1, TGFbeta2, and TGFbeta3) During Embryonic Rat Testis Development

Biology of Reproduction. Jun, 1999  |  Pubmed ID: 10330085

The objective of the current study was to determine the role of transforming growth factor beta (TGFbeta) during seminiferous cord formation and embryonic testis development. The expression pattern of mRNA for TGFbeta isoforms was evaluated during testis development through a quantitative reverse transcription-polymerase chain reaction (QRT-PCR) procedure. Expression of mRNA for TGFbeta1 was highest at postnatal day 0 (P0) and P10. In contrast, TGFbeta2 was high at embryonic day 15 (E15), declined at E16, and showed a transient increase at P0 through P3 of testis development. Interestingly, expression of mRNA for TGFbeta3 was high during embryonic development and then declined after P3. Immunohistochemical localization of TGFbeta1 and TGFbeta2 demonstrated expression in Sertoli cells at E14 and in the seminiferous cords at P0. Selective interstitial cells expressed high concentrations of TGFbeta1 and TGFbeta2 in P0 testis. TGFbeta3 was expressed in selective cells at the junction of the E14 testis and mesonephros. The cells expressing TGFbeta3 in the testis appeared to be preperitubular cells that resided around the seminiferous cords. TGFbeta3 was localized to gonocytes in P0 testis. TGFbeta1 was found to have no influence on seminiferous cord formation in embryonic organ cultures of E13 testis. In contrast, growth of both E13 and E14 embryonic organ cultures was inhibited by TGFbeta1 and resulted in reduced testis size (40% of controls) with fewer cords present. A P0 testis cell culture and thymidine incorporation assay were used to directly examine the effects of recombinant TGFbeta1. TGFbeta1 alone had no influence on thymidine incorporation in P0 testis cell cultures when compared to controls. Interestingly, TGFbeta1 inhibited epidermal growth factor (EGF), and 10% calf serum stimulated P0 testis cell growth but not FSH-stimulated growth. Therefore, TGFbeta1 appears to inhibit testis growth in both the embryonic and early postnatal periods. The hormonal regulation of TGFbeta expression was measured using P0 testis cell cultures and a QRT-PCR procedure for each TGFbeta isoform. High concentrations of EGF stimulated expression of mRNA for TGFbeta1 after 24 h but suppressed expression of TGFbeta3. In contrast, there was no effect of FSH on TGFbeta isoform expression. In summary, TGFbeta regulates embryonic and P0 testis growth through inhibiting the actions of positive growth factors such as EGF. In addition, EGF but not FSH appears to regulate TGFbeta isoform expression. Combined observations from the present study demonstrate that TGFbeta isoforms are differentially expressed and appear to be regulators of testis growth during the embryonic and early postnatal periods.

Role of Neurotropins in Rat Embryonic Testis Morphogenesis (cord Formation)

Biology of Reproduction. Jan, 2000  |  Pubmed ID: 10611077

The process of seminiferous cord formation is the first morphological event that differentiates a testis from an ovary and indicates male sex determination. Cord formation occurs by embryonic Day 14 (Day 0 = plug date; E14) in the rat. A series of experiments were conducted to determine if neurotropins and their receptors are important for the process of rat embryonic cord formation. The expression of low affinity neurotropin receptor (p75/LNGFR) was determined by immunohistochemistry on sections of both testis and ovary from E13 through birth (Day 0, P0) with an antibody to p75/LNGFR. The staining for p75/LNGFR was present in the mesonephros of E13 gonads and in a sex-specific manner appeared around developing cords at E14 in the embryonic testis. At birth, staining for p75/LNGFR was localized to a single layer of cells (i.e., peritubular cells) that surrounded the seminiferous cords. The genes for both neurotropin 3 (NT3) and for corresponding high affinity neurotropin trkC receptor were found to be expressed in the E14 rat testis, as well as other neurotropins and receptors. Immunocytochemical analysis of E14 rat testis demonstrated that NT3 was localized to the Sertoli cells and trkC was present in individual cells of the interstitium at E16 and in selected preperitubular cells at E18. Previously, the peritubular cells adjacent to the cords were demonstrated to be derived from migrating mesonephros cells around the time of cord formation. To determine if neurotropins were involved in cord formation, the actions of neurotropins were inhibited. A high affinity neurotropin receptor (trk)-specific kinase inhibitor, K252a, was used to treat organ cultures of testes from E13 rats prior to cord formation. Treatment of E13 testis organ cultures with K252a completely inhibited cord formation. K252a-treated organ cultures of E14 testis that contained cords did not alter cord morphology. A second experiment to inhibit neurotropin actions utilized a specific antagonist trk-IgG chimeric fusion protein and E13 testis organ cultures. The trk-IgG molecules dimerize with endogenous trk receptors and inhibit receptor signaling and activation of ligand function. Forty percent of E13 testis organ cultures treated with trkC-IgG had significantly reduced cord formation. TrkA-IgG had no effect on initiation of cords; however, in fifty percent of the treated organs, a "swollen" appearance of the cord structures was observed. Experiments using trkB-IgG chimeric protein on E13 organ cultures had no effect on cord formation or cord morphology. The testes from trkC and NT3 knockout mice were examined to determine if there were any morphological differences in the testis. NT3 knockouts appeared to have normal cord morphology in E15 and E17 testis. TrkC knockout mice also had normal cord morphology in E14 and P0 testis. Both NT3 and trkC knockout-mice testis had less interstitial area than wild-type controls. In addition, the trkC knockout mice have an increased number of cells expressing p75LNGFR within the cords when compared to controls or NT3 knockout mice. Combined observations suggest compensation between the different neurotropin ligands, receptors, and/or possibly different growth factors for this critical biological process. In summary, results suggest a novel nonneuronal role for neurotropins in the process of cord formation during embryonic rat testis development. The hypothesis developed is that neurotropins are involved in the progression of male sex differentiation and are critical for the induction of embryonic testis cord formation.

Programmatic Goals and Approaches to Onchocerciasis

Lancet. May, 2000  |  Pubmed ID: 10905239

Simulium Vittatum (Diptera: Simuliidae) and Lutzomyia Longipalpis (Diptera: Psychodidae) Salivary Gland Hyaluronidase Activity

Journal of Medical Entomology. Sep, 2000  |  Pubmed ID: 11004788

Hyaluronidase activity in the salivary gland homogenates of Simulium vittatum (Zetterstedt) is described, and its optimal pH determined. Salivary activity was reduced significantly after a blood meal, indicating that it was secreted after blood feeding. Phlebotomus papatasi (Scopoli) also exhibited salivary hyaluronidase activity. These results indicate that hematophagous pool-feeding insects may secrete this enzyme to help the spread of salivary antihemostatic agents in the vicinity of the feeding lesion, and perhaps to increase the size of the feeding lesion itself. Additionally, this enzyme may affect local host immune reactions and promote arboviral transmission.

Expression and Action of Neurotropin-3 and Nerve Growth Factor in Embryonic and Early Postnatal Rat Testis Development

Biology of Reproduction. Dec, 2000  |  Pubmed ID: 11090428

The current study examines the expression and potential actions of neurotropin-3 (NT3), nerve growth factor (NGF), and their receptors during morphological sex determination (seminiferous cord formation) and perinatal rat testis development. The expression of neurotropins and their receptors was analyzed with immunohistochemistry. Cellular localization of neurotropin ligand and receptor proteins changed during embryonic testis development. Neurotropin-3 was localized to Sertoli cells at Embryonic Day 14 (E14), was present in gonocytes at Postnatal Day 0 (P0), and after birth became localized to the interstitium and Sertoli cells (P3-P5). The expression of trk C (the high affinity receptor for NT3) was localized to mesonephric ducts and cells surrounding the cords (E14-E18). In addition, Sertoli cells and preperitubular cells surrounding the cords at E14 also stained for trk C. Neurotropin-3 was expressed in gonocytes and Sertoli cells at P0-P5. Nerve growth factor was detected in Sertoli cells at E14, was clearly in Sertoli and interstitial cells at E16 and E18, and in Sertoli, germ, and interstitial cells from P0-P5. The expression of trk A (the high affinity receptor for NGF) was located in Sertoli and interstitial cells at E16-P5. To determine the actions of neurotropins during embryonic and perinatal testis development, experiments were conducted on E13 and P0 testis. Antisense oligonucleotide experiments with NT3 were used on E13 testis organ cultures to determine effects on seminiferous cord formation. Cord formation was inhibited in 40% of the organ cultures treated with the antisense NT3 oligonucleotides, while no inhibition was observed with sense oligonucleotides. In P0 testis cultures, both NT3 and NGF alone and in combination stimulated thymidine incorporation into DNA. Therefore, the neurotropins are involved in embryonic morphological events (cord formation; NT3) and in growth of the perinatal testis (P0; NT3 and NGF). To define further the growth effects of neurotropins on testis development, expression of transforming growth factor alpha and beta (TGF alpha and TGF beta) were examined in response to neurotropins. The P0 testis cultures were treated with neurotropins, and expression of mRNA for TGF alpha and TGF beta was analyzed utilizing a quantitative reverse transcription-polymerase chain reaction assay. Nerve growth factor and NT3 alone or in combination inhibited expression of mRNA for TGF alpha while NT3 increased mRNA expression of epidermal growth factor receptor. The combination treatment of neurotropins inhibited expression of TGF beta 1 and increase expression of TGF beta 3. In summary, observations suggest that NT3, NGF, trk A, and trk C are localized to cells critical to seminiferous cord formation and appear to be important regulators of morphological sex determination. In addition to these morphological effects, both NT3 and NGF stimulate P0 testis growth and may elicit their action through altering the expression of locally produced growth factors such as TGF alpha and TGF beta. Taken together these results suggest that neurotropins are regulators of paracrine cell-cell interactions that result in morphological sex determination and perinatal testis growth.

The Continuing Search for Proper Perspective: Whose Reasonableness Should Be at Issue in a Prescription Product Design Defect Analysis?

Specialty Law Digest. Health Care Law. Dec, 2000  |  Pubmed ID: 11149134

Horn Fly (Diptera: Muscidae) Saliva Targets Thrombin Action in Hemostasis

Journal of Medical Entomology. May, 2000  |  Pubmed ID: 15535586

The horn fly, Hematobia irritans (L.), is an important pest of livestock because the adult stage of both sexes are aggressive blood-feeders. Remarkably, even though horn fly adults feed recurrently on their hosts as ectoparasites, these flies lack the ADP-responsive antiplatelet aggregation and vasodilatory antihemostatic systems described for other blood-feeding Diptera. Horn fly salivary gland extracts do interfere with the normal coagulation process as demonstrated by the recalcification time assay. Using this as a baseline, the effects of saliva on recalcification time, activated partial thromboplastin time, prothrombin time, and thrombin time were measured to determine which arm(s) of the coagulation cascade might be impacted. Factor-deficient plasma assays also were used to measure possible perturbations in clotting. Gland-free saliva delayed the recalcification time as well as the activated partial thromboplastin time, prothrombin time, and thrombin time. Saliva also further delayed clotting times of plasmas deficient in factor V, factor VIII, and factor XIII, indicating that other factors in the coagulation cascade were inhibited. Although horn fly saliva did not alter the ability of deficient plasma reconstituted with factor X to clot, it did inhibit deficient plasma reconstituted with factor II (thrombin). Antithrombin activity in saliva was confirmed by its ability to interfere with thrombin hydrolysis of fibrinogen, its normal substrate, and by its inhibition of thrombin action on a chromagenic substrate that mimics the hydrolytic site of fibrinogen. Thus, horn fly saliva contains a factor that specifically targets thrombin, a key component in the coagulation cascade. While the biochemical mechanisms of inhibition may vary, this antihemostatic characteristic is shared with other zoophilic Diptera such as black flies, Simulium spp., and tsetse, Glossina morsitans morsitans Westwood, that feed on ungulates.

Role of Transforming Growth Factor-alpha and the Epidermal Growth Factor Receptor in Embryonic Rat Testis Development

Biology of Reproduction. Mar, 2000  |  Pubmed ID: 10684787

Embryonic testis development requires the morphogenesis of cords and growth of all cell populations to allow organ formation. It is anticipated that coordination of the growth and differentiation of various cell types involves locally produced growth factors. The current study was an investigation of the hypothesis that transforming growth factor-alpha (TGF-alpha) is involved in regulating embryonic testis growth. TGF-alpha has previously been shown to function in the postnatal testis. TGF-alpha and other members of the epidermal growth factor (EGF) family act through the epidermal growth factor receptor (EGFR) to stimulate cell proliferation and tissue morphogenesis. To understand the potential actions of TGF-alpha in the embryonic testis, general cell proliferation was investigated. Characterization of cell proliferation in the rat testis throughout embryonic and postnatal development indicated that each cell type has a distinct pattern of proliferation. Germ cell growth was transiently suppressed around birth. Interstitial cell growth was high embryonically and decreased to low levels around birth. A low level of Sertoli cell proliferation was observed at the onset of testis cord formation. Sertoli cell proliferation in early embryonic development was low; the levels were high later in embryonic development and remained high until the onset of puberty. Both TGF-alpha and the EGFR were shown to be expressed in the embryonic and postnatal rat and mouse testis. Perturbation of TGF-alpha function using neutralizing antibodies to TGF-alpha on testis organ cultures dramatically inhibited the growth of both embryonic and neonatal testis. TGF-alpha antibodies had no effect on cord formation. The TGF-alpha antibody was found to be specific for TGF-alpha in Western blots when compared to EGF and heregulin. Testis growth was also inhibited by perturbation of EGFR signaling using an EGFR kinase inhibitor. Therefore, TGF-alpha appears to influence embryonic testis growth but not morphogenesis (i.e., cord formation). Treatment of embryonic testis organ cultures with exogenous TGF-alpha also perturbed development, leading to an increased proliferation of unorganized cells. Testis from EGFR and TGF-alpha knockout mice were analyzed for testis morphology. TGF-alpha knockout mice had no alterations in testis phenotype, while EGFR knockout mice had a transient decrease in the relative amount of interstitial cells before birth. Observations suggest that there may be alternate or compensatory factors that allow testis growth to occur in the apparent absence of TGF-alpha actions in the mutant mice. In summary, the results obtained suggest that TGF-alpha is an important factor in the regulation of embryonic testis growth, but other factors will also be involved in the process.

Monitoring for the Emergence of New Foci of Onchocerciasis (river Blindness) in the Americas

Transactions of the Royal Society of Tropical Medicine and Hygiene. Jan-Feb, 2000  |  Pubmed ID: 10748915

Delivery of Endothelial Cells to Balloon-dilated Rabbit Arteries with Use of a Local Delivery Catheter

Journal of Vascular and Interventional Radiology : JVIR. May, 2001  |  Pubmed ID: 11340139

Experiments were performed to determine if a local delivery catheter could deliver endothelial cells that would be retained on the luminal surface of balloon-dilated arteries.

Actions of the Endocrine Disruptor Methoxychlor and Its Estrogenic Metabolite on in Vitro Embryonic Rat Seminiferous Cord Formation and Perinatal Testis Growth

Reproductive Toxicology (Elmsford, N.Y.). May-Jun, 2001  |  Pubmed ID: 11390175

The current study examines the actions of methoxychlor and its estrogenic metabolite, 2, 2-bis-(p-hydroxyphenyl)-1, 1, 1-trichloroethane (HPTE), on seminiferous cord formation and growth of the developing rat testis. The developing testis in the embryonic and early postnatal period is likely more sensitive to hormonally active agents than at later stages of development. Embryonic day 13 (E13) testis organ cultures were treated with either 0.2, 2, or 20 microM methoxychlor or 1, 3, 6, 15, 30, or 60 microM HPTE to examine effects on cord formation. No concentration of methoxychlor completely inhibited cord formation. However, cord formation was abnormal with the presence of a reduced number of cords and appearance of "swollen" cords at the 2 and 20 microM concentrations of methoxychlor. The swollen cords were due to an increase in the number of cells in a cord cross section and reduction of interstitial cell numbers between cords. Treatment of embryonic day 13 (E13) testes with HPTE caused abnormal cord formation at the 3 microM and 6 microM concentrations, and completely inhibited cord formation at the 15, 30, and 60 microM concentrations. In addition to the estrogenic metabolite HTPE, methoxychlor can also be metabolized into anti-androgenic compounds. Therefore, to determine the spectrum of potential actions of methoxychlor on testis development, different concentrations of estradiol, testosterone, and an anti-androgen (flutamide) were utilized to determine their effects on E13 testis organ culture morphology. Estradiol (1 microM) and flutamide (0.1microM) both inhibited seminiferous cord formation in E13 testis organ cultures. Therefore, methoxychlor may be acting through the androgen and/or estrogen receptors to elicit its actions on seminiferous cord formation. Reverse transcription polymerase chain reaction (PCR) (RT-PCR) confirmed the presence of estrogen receptor alpha (ERalpha) mRNA from embryonic day 14 (E14) through postnatal day 5 (P5) while estrogen receptor beta (ERbeta) mRNA did not appear until approximately E16 of testis development. Androgen receptor (AR) expression was present from E14 through P5 of testis development, but at apparently reduced levels at E14 and E16. Immunohistochemical analysis localized ERalpha to the cells of the seminiferous cords at E14 though P5 while ERbeta was present in cells of the interstitium at E16 and P0. Androgen receptor was localized to germ and interstitial cells. The effects of methoxychlor, HPTE, estradiol, and testosterone on cell growth of perinatal testes was determined with a thymidine incorporation assay in postnatal day zero (P0) testis cell cultures. Methoxychlor (0.002, 0.02, and 0.2 microM) and HPTE (2 and 20 microM) stimulated thymidine incorporation in P0 testis cell cultures in a similar manner to estradiol (0.01, 0.1, and 1 microM). In addition, testosterone (0.1 microM) also stimulated thymidine incorporation in P0 testis cultures. Observations suggest that methoxychlor and its metabolite HPTE can alter normal embryonic testis development and growth. The actions of methoxychlor and HPTE are likely mediated in part through the steroid receptors confirmed to be present in the developing testis.

Polymorphism of the Thrombostasin Gene in the Horn Fly (Haematobia Irritans) Revealed in a CDNA Library and in Genomic DNA

Molecular Genetics and Genomics : MGG. Oct, 2001  |  Pubmed ID: 11683272

Thrombostasin (TS) is a newly described thrombin-inhibiting protein isolated from the saliva of the horn fly (Haematobia irritans), a blood-sucking ectoparasite of cattle. This report provides a detailed characterization of the TS gene and the first analysis of the allelic complexity of a gene for an anti-hemostatic protein from a blood-feeding insect. Multiple point mutations at fixed positions in the TS gene were identified in a cDNA library prepared from mRNA isolated from horn fly salivary glands. When translated, the variant mRNAs would specify five biochemically active peptides that differ in molecular weight, isoelectric point and predicted secondary structure. Allelic variation with the same mutation pattern was revealed in the genomes of individual flies collected in the field and sampled from a long-standing laboratory colony. Approximately 60% of flies examined carried heterozygous alleles, including five additional alleles not found in the cDNA library. Comparative analysis of the allelic mutations and the predicted effects on secondary structures of the active proteins produced suggest that the TS gene may be undergoing evolutionary selection.

Expression, Action, and Regulation of Transforming Growth Factor Alpha and Epidermal Growth Factor Receptor During Embryonic and Perinatal Rat Testis Development

Journal of Andrology. Nov-Dec, 2001  |  Pubmed ID: 11700850

The objective of the current study was to extend previous observations and examine the expression pattern and effects of transforming growth factor alpha (TGFalpha) and epidermal growth factor receptor (EGFR) on embryonic testis morphogenesis and growth. The expression of TGFalpha was determined after morphological sex determination (seminiferous cord formation at embryonic day 13 [ED13]) through perinatal testis development (postnatal day 5 [PD5]) with a quantitative reverse transcription-polymerase chain reaction procedure. Expression of messenger RNA (mRNA) for TGFalpha appeared to be more dynamic during testis development when compared with the expression of mRNA for EGFR. Message for TGFalpha was reduced at ED16 and PD4, and was elevated at PD0 during testis development. In contrast, EGFR mRNA levels were negligible at ED15 and were elevated constitutively from ED16 through PD5. Immunohistochemistry was conducted at ED14, ED16, ED19, PD0, PD3, and PD5 to localize cellular expression of both TGFalpha and EGFR. At ED16, positive staining for EGFR was localized to the cords, and by ED19, was mainly in the cords with slight expression in the interstitium. From PD0 to PD5, positive staining for EGFR was detected in the germ, Sertoli, and interstitial cells. Immunohistochemistry for TGFalpha detected localization at ED14 and ED16 to the Sertoli cells and to specific cells in the interstitium. From ED19 through PD5, TGFalpha was detected in the Sertoli, germ, and interstitial cells, and in endothelial cells within the interstitium. To determine the effects of TGFalpha on embryonic testis growth and seminiferous cord formation, ED13 testis organ cultures were treated with sense and antisense TGFalpha oligonucleotides. Antisense TGFalpha inhibited testis growth by 25%-30% in ED13 testis organ cultures when compared with sense oligonucleotide control pairs. To examine the effects of TGFalpha on perinatal testis growth, PD0 testis cultures were treated with different doses of TGFalpha. TGFalpha increased thymidine incorporation into DNA in PD0 testis cultures. Therefore, TGFalpha appears to have actions on both embryonic and perinatal testis growth. The regulation of TGFalpha and EGFR mRNA levels were examined using PD0 testis cultures treated with hormones that stimulate testis growth. Follicle-stimulating hormone (FSH) stimulated (P < .05) and testosterone tended to stimulate (P < .07) mRNA expression of EGFR. Epidermal growth factor stimulation of PD0 testis cultures did not affect levels of mRNA expression for EGFR, but did suppress expression of mRNA for TGFalpha. These results taken together demonstrate that TGFalpha can act to regulate early embryonic and perinatal testis growth. Furthermore, TGFalpha and EGFR expression can be regulated through growth stimulatory hormones such as FSH and testosterone.

Thrombostasin: Purification, Molecular Cloning and Expression of a Novel Anti-thrombin Protein from Horn Fly Saliva

Insect Biochemistry and Molecular Biology. Mar, 2002  |  Pubmed ID: 11804804

Thrombostasin (TS), a novel protein found in the saliva of Haematobia irritans (horn fly), was purified by high-performance liquid chromatography from the saliva of field-collected insects. This protein, which inhibits thrombin, accounts for anti-clotting activity in horn fly saliva [J. Med. Entomol. 37 (2000) 416] and is the first purified anti-hemostatic factor described from the Stomoxyinae, a large group of blood-feeding insects that are major pests of livestock world-wide. The purified TS had an apparent molecular weight of 16.7 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and revealed two isoelectric groups with isoelectric points (pIs) of approximately 4.6 and 4.8. Mass spectroscopy analysis, however, resulted in at least three major isoforms that range in mass from 9213 to 9274 Da. A 243-bp coding sequence was obtained from cDNA by using a degenerate primer deduced from the N-terminal sequence of the purified TS. The conceptual translation of the 243-bp sequence showed that the 81-amino-acid peptide, whose first 30 amino acids match those of the N-terminal sequence, had a predicted mass of 9213 Da with pI 4.14. A full-length TS cDNA was generated by rapid amplification of cDNA ends of the 5' and sequential polymerase chain reaction (PCR) amplification. It contained a 5'-end 12-bp segment preceding the putative ATG start codon, followed by a 54-bp sequence corresponding to a secretory signal and an additional 228-bp coding sequence preceding residues revealed by N-terminal sequencing of purified TS. The fidelity of the PCR-generated TS sequence was confirmed in genomic DNA and by biological activity of recombinant TS produced in a baculovirus expression system. Database comparisons revealed no homology between TS and other known molecules. Because of the paucity of other anti-hemostatic factors in horn fly saliva, TS may play a critical role in maintenance of the ectoparasitic lifestyle of horn flies.

Gene Therapy, Electroporation, and the Future of Wound-healing Therapies

Facial Plastic Surgery : FPS. Feb, 2002  |  Pubmed ID: 11823933

Chronic wounds are a major clinical problem with notable morbidity. Treatment is usually supportive and results in significant healthcare expenditures. It is estimated that 1.25 million people are burned each year in the United States and that 6.5 million have chronic skin ulcers caused by pressure, venous stasis, or diabetes mellitus. Wound healing is a complex and lengthy process, often taking up to 12 months to complete. The cost of treating poorly healing foot wounds in the United States has been estimated at $1 billion per year. A number of topical commercial products have become available to provide an optimal environment for problematic open wounds. Topical platelet-derived growth factor (PDGF)-BB has proven effective in improving healing in impaired wounds but has the disadvantage of requiring large and repeated doses. More recently, investigators have focused on the possibility of inserting genes encoding for growth factors such as PDGF-BB into the cells participating in the wound-healing response. This approach offers the potential of single-dose growth factor treatment of chronic wounds. There are several approaches for gene insertion, including viral vectors, gene guns, and electroporation. This article reviews the strategies and potential of these approaches, with a focus on electroporation.

Testis Developmental Phenotypes in Neurotropin Receptor TrkA and TrkC Null Mutations: Role in Formation of Seminiferous Cords and Germ Cell Survival

Biology of Reproduction. Jun, 2002  |  Pubmed ID: 12021070

The objective of the present study was to determine if the neurotropin receptors trkC and trkA are involved in embryonic testis development. These receptors bind neurotropin 3 and nerve growth factor, respectively. The hypothesis tested was that the absence of trkC or trkA receptors will have detrimental effects on testis development and morphology. The trkA and trkC homozygote knockout (KO) mice generally die either at or shortly after birth. Therefore, heterozygote mice were mated to obtain homozygote gene KO mice at Embryonic Day (E) 13, E14, E17, and E19 of gestation, with E0 being the plug date. Gonads from approximately 80 embryos were collected and fixed, and each embryo was genotyped. To determine gonadal characteristics for each genotype, the number of germ cells, number of seminiferous cords, seminiferous cord area, and interstitial area were calculated at each developmental age. Germ cell numbers varied in trkA gene KO mice from those of wild-type mice at each age evaluated. In trkC gene KO mice, differences were detected in germ cell numbers when compared to wild-type mice at E17 and E19. At E19, germ cell numbers were reduced in both trkA and trkC gene KO mice when compared to wild-type animals. Apoptosis was evaluated in testes of wild-type, trkC gene KO, and trkA gene KO mice to determine if the alteration in germ cell numbers at each developmental age was influenced by different patterns of germ cell survival or apoptosis. No differences were found in germ cell apoptosis during embryonic testis development. Interestingly, trkA gene KO mice that survived to Postnatal Day 19 had a 10-fold increase in germ cell apoptosis when compared to germ cells in wild-type mice. Evaluation of other morphological testis parameters demonstrated that trkC KO testes had reduced interstitial area at E13, reduced number of seminiferous cords at E14, and reduced seminiferous cord area at E19. The trkA gene KO testes had a reduction in the number of seminiferous cords at E14. Histology of both trkA and trkC gene KO testes demonstrated that these gonads appear to be developmentally delayed when compared to their wild-type testis counterparts at E13 during testis development. The current study demonstrates that both trkA and trkC neurotropin receptors influence germ cell numbers during testis development and events such as seminiferous cord formation.

Orientation of Onchocerca Lienalis Stiles (Filarioidea: Onchocercidae) Microfilariae to Black Fly Saliva

Journal of Medical Entomology. Nov, 2002  |  Pubmed ID: 12495191

Black flies (Simulium spp.) are intermediate hosts and vectors of parasitic nematodes belonging to the genus Onchocerca (Filarioidea Onchocercidae). Infection and subsequent transmission of infective third-stage larvae occur at the vertebrate host-skin interface. Experimental evidence presented here demonstrates that Onchocerca lienalis Stiles microfilariae orient to one or more components (microfilarial orientation factor [s]; MOF) in black fly saliva. MOFs may serve as a means for microfilariae to find and infect black flies during the act of blood-feeding. Directed movement through the host's skin to the bite site is necessary because Onchocerca spp. microfilariae do not circulate in the blood. The substance directing microfilarial orientation appears to be a salivary protein, but it is not the Simulium vittatum Zetterstedt erythema protein (SVEP) described from New World Simulium spp. These results support earlier field observations that associated increased numbers of cutaneous microfilariae with black fly feeding and indicate that a fundamental molecular mechanism linked to vector saliva may be key for the maintenance of the life cycle of Onchocerca spp. Salivary molecules that induce orientation of microfilariae to the bite site are potential targets for use in transmission-blocking vaccines to uncouple this primary vector infection step.

Identification of Mosquito Avian-derived Blood Meals by Polymerase Chain Reaction-heteroduplex Analysis

The American Journal of Tropical Medicine and Hygiene. May, 2002  |  Pubmed ID: 12201598

A polymerase chain reaction (PCR) heteroduplex assay (HDA) was developed to identify avian derived mosquito blood meals to the species level. The assay used primers amplifying a fragment of the cytochrome B gene from vertebrate but not invertebrate species. In Culex tarsalis fed on quail, PCR products derived from the quail cytochrome B gene were detected seven days post-engorgement. In an analysis of wild-caught mosquitoes, 85% of blood-fed mosquitoes produced detectable PCR products. Heteroduplex patterns obtained from bird-derived PCR products were found to permit the unambiguous identification of all species examined. No intraspecific variation in HDA patterns was found. The PCR-HDA was used to characterize blood meals in wild caught Cx. tarsalis. Of the 67 blood meals analyzed, 60% were derived from avian sources. Of the avian blood meals, 65% were derived from a single host, the common grackle.

Mood and Sex of Participant in Perception of Happy Faces

Perceptual and Motor Skills. Aug, 2002  |  Pubmed ID: 12365265

The influences of mood-state and sex of subject were examined for ratings of the emotional intensity of videotaped facial expressions of happiness. 102 subjects who were classified by sex and their scores on the Beck Depression Inventory provided ratings of the faces. A significant sex by mood-state interaction indicated that ratings of intensity by men and women were influenced differently by mood-state, and these findings are interpreted within the framework of the Affect Infusion Model. The results support our hypothesis that men and women tend to rely preferentially on low and high affect infusion strategies, respectively. The findings further suggest that the cognitive effect of affect infusion on the magnitude of perceived intensity of facial affect could be influenced by mood-state via differences in cognitive effort subjects employ when in a dysphoric or nondysphoric mood.

The Effects of Autologous Platelet Gel on Wound Healing

Ear, Nose, & Throat Journal. Aug, 2003  |  Pubmed ID: 14503096

Laser resurfacing techniques have become a popular means of achieving rejuvenation of damaged skin. Interest is great in attempting to speed re-epithelialization and healing so that patients can return to their normal activities as quickly as possible. Previous studies have demonstrated that wounds heal more quickly when they are covered and kept moist than when they are left open to the air. Until now, no study has been conducted to investigate whether the healing process of a superficial skin burn might be accelerated by the use of an autologous platelet gel as a biologic dressing. Our study of five pigs showed that autologous platelet gel can influence wound healing by stimulating an intense inflammatory process that leads to highly significant increases in the production of extracellular matrices and granulation tissue. The platelet gel accelerated vascular ingrowth, increased fibroblastic proliferation, and accelerated collagen production. However, the gel did not appear to accelerate re-epithelialization. The aggressive production of granulation tissue and the acceleration of collagen production might mean that autologous platelet gel will have a future role in the treatment of burns because the highly vascularized bed it helps create should promote the success of skin grafting in patients with deep partial-thickness and full-thickness burns.

Avian Host Preference by Vectors of Eastern Equine Encephalomyelitis Virus

The American Journal of Tropical Medicine and Hygiene. Dec, 2003  |  Pubmed ID: 14740882

An important variable in the amplification and escape from the enzootic cycle of the arboviral encephalitides is the degree of contact between avian hosts and mosquito vectors. To analyze this interaction in detail, blood-fed mosquitoes that were confirmed vectors of eastern equine encephalomyelitis (EEE) virus were collected in 2002 from an enzootic site in central Alabama during the time this virus was actively transmitted. Avian-derived blood meals were identified to the species level of the host, and the proportion derived from each species was compared with the overall composition of the avifauna at the study site. The EEE vector mosquito species fed significantly more on some bird species and less on other species than expected given the overall abundance, biomass, or surface area of the local avifauna. When viewed collectively, these data suggest that these mosquitoes are selectively targeting particular avian species.

The Percutaneous Columellar Strut

American Journal of Rhinology. Nov-Dec, 2003  |  Pubmed ID: 14750612

Understanding tip support mechanisms is essential for nasal surgery, especially for preservation or augmentation of tip projection.

Quantification of O,o'-dityrosine, O-nitrotyrosine, and O-tyrosine in Cat Urine Samples by LC/ Electrospray Ionization-MS/MS Using Isotope Dilution

Analytical Chemistry. Jan, 2003  |  Pubmed ID: 12553760

Quantification of o-tyrosine, o-nitrotyrosine, and o,o'dityrosine from cat urine samples was achieved by LC/ electrospray ionization-MS/MS (LC/ESI-MS/MS) using an isotope dilution technique in multiple reaction monitoring mode before butylation of o,o'-dityrosine and after butylation of o-tyrosine and o-nitrotyrosine. This novel approach of amino acids butylation enhanced the MS response by a factor of 7-fold for o-tyrosine and 6-fold for o-nitrotyrosine and decreased the overall chemical background noise. Butylation of o,o'-dityrosine resulted in a lower MS response as a result of the formation of both mono- and doubly butylated species. The mean recovery for the oxidized amino acids was estimated at 73 +/- 2%. The limits of quantitation of NO2-Tyr butyl ester, o-Tyr butyl ester, and di-Tyr in cat urine samples were calculated at 14.5, 28.2 and 140.9 nM, respectively. The oxidized amino acids levels in cat urine extracts ranged from 157 to 250 ng/day for o-Tyr and from 3,289 to 11,803 ng/day for di-Tyr. NO2-Tyr was found in only two urine extracts at levels below 58 ng/day. A certain trend of correlation was observed between o,o'-dityrosine and o-tyrosine when comparing these values against their respective creatinine amounts. A comparison of the data gathered from the ThermoFinnigan TSQ 7000 and Micromass Q-TOF instruments revealed several advantages of using the Q-TOF regarding the exact mass measurement, a lower ion suppression effect and the possibility to perform analyses in full scan product ion mode. These results demonstrate that a Q-TOF instrument can be a good alternative to classical triple quadrupole for quantitative purposes on a relatively small linear dynamic range (4 orders of magnitude for the Q-TOF, as compared to 6 for the triple quadrupole).

Ultraviolet Protectants: Causative Agents for Screen and Image Artifacts in Radiography

Radiology. Apr, 2003  |  Pubmed ID: 12601196

To determine the specific causative agent(s) and mechanism of formation of opacity artifacts seen on some radiographs acquired at the authors' facility.

Chemotactic Role of Neurotropin 3 in the Embryonic Testis That Facilitates Male Sex Determination

Biology of Reproduction. Jun, 2003  |  Pubmed ID: 12606390

The first morphological event after initiation of male sex determination is seminiferous cord formation in the embryonic testis. Cord formation requires migration of pre-peritubular myoid cells from the adjacent mesonephros. The embryonic Sertoli cells are the first testicular cells to differentiate and have been shown to express neurotropin-3 (NT3), which can act on high-affinity trkC receptors expressed on migrating mesonephros cells. NT3 expression is elevated in the embryonic testis during the time of seminiferous cord formation. A trkC receptor tyrophostin inhibitor, AG879, was found to inhibit seminiferous cord formation and mesonephros cell migration. Beads containing NT3 were found to directly promote mesonephros cell migration into the gonad. Beads containing other growth factors such as epidermal growth factor (EGF) did not influence cell migration. At male sex determination the SRY gene promotes testis development and the expression of downstream sex differentiation genes such as SOX-9. Inhibition of NT3 actions caused a reduction in the expression of SOX-9. Combined observations suggest that when male sex determination is initiated, the developing Sertoli cells express NT3 as a chemotactic agent for migrating mesonephros cells, which are essential to promote embryonic testis cord formation and influence downstream male sex differentiation.

Frequency of Luteinizing Hormone Pulses in Cattle Influences Duration of Persistence of Dominant Ovarian Follicles, Follicular Fluid Concentrations of Steroids, and Activity of Insulin-like Growth Factor Binding Proteins

Animal Reproduction Science. Jul, 2003  |  Pubmed ID: 12695054

The objectives of the present study were to determine how varying frequency of LH pulses as controlled by varying treatments with progesterone (P4) in cattle would affect: (1) concentration of steroid hormones and activity of insulin-like growth factor binding proteins (IGFBPs) in the ovarian follicular fluid and blood plasma, and (2) duration of persistence of largest ovarian follicles. There were four treatment groups (n=7 per group) and a control group (n=5) of mature, non-lactating beef cows. Treatments were: (1) two progesterone releasing intravaginal devices (PRIDs) for 16 days (2PRID); (2) a half PRID for 16 days (0.5PRID); (3) two PRIDs for 8 days, then a half PRID for 8 days (2-0.5PRID); or (4) a half PRID for 8 days, then two PRIDs for 8 days (0.5-2PRID). Treatment was initiated on the fifth day of the estrous cycle, which was designated as Day 0, and continued for 16 days. All P4-treated females were administered prostaglandin F2alpha on Day 0 and 1 to regress their corpora lutea. Frequency of LH pulses was greater during treatment with the smaller dose of P4 compared with treatment with the larger dose of P4 and the control group. Ovarian follicles were classified into five categories based on ultrasonographic observations: growing (G); atretic (A); growing dominant (GD); growing persistent (GP); or atretic persistent (AP). At ovariectomy on Day 16, the largest and second largest follicles collected were re-classified into five categories based on follicular concentration of steroids. Classification of the largest follicle collected on Day 16 was influenced by treatment (P<0.005), with the 2PRID group having A follicles, the 2-0.5PRID group GP follicles, the 0.5-2PRID group AP follicles, and the 0.5PRID group GD and GP follicles. Concentrations of 17beta-estradiol (E2) were greatest in GD and GP follicles (P<0.05). There was less (P<0.05) activity of IGFBP-2 in GD follicles and less (P<0.05) activity of IGFBP-3 in GD and GP follicles than other follicles. Activity of IGFBP-4 and -5 was greater (P<0.05) in A and AP follicles than G, GD, and GP follicles. Maintenance of a frequent release of LH pulses over a 16-day period did not result in maintenance of persistent follicles throughout this period indicating that duration of dominance of these follicles is finite even when there is frequent release of LH pulses. Follicular atresia is associated with greater activity of IGFBP-2, -4, -5, and greater concentrations of P4 in follicles, whereas growing dominant and persistent follicles contained greater concentrations of E2, androstenedione (A4), and less IGFBP-2 activity than follicles of other classes. Follicle classifications based on ultrasonography or follicular concentration of steroids did differ (P<0.05) for the largest follicles from the 2PRID group. Two follicles in this group appeared as GD follicles by ultrasonography, but these were atretic based on follicular steroid contents. Objective 1 of the present study yielded the conclusion that concentrations of steroid hormones in follicular fluid and blood plasma could be predictably controlled by regulating the frequency of LH pulses with varying doses of P4. Objective 2 yielded the conclusion that maintain frequent release of LH pulses over a 16-day period could not maintain persistent follicles throughout this period, indicating that duration of dominance of these follicles is finite even when there is frequent release of LH pulses. Follicular atresia in the present study was associated with increased follicular fluid activity of IGFBP-2, -4, -5, and P4, whereas growing dominant and persistent follicles contained greater concentrations of E2, A4, and less IGFBP-2 activity than follicles of other classes.

Patients' Understanding of Herbal Product "suggested Use" and "disclaimer" Statements

The Annals of Pharmacotherapy. Jul-Aug, 2003  |  Pubmed ID: 12841838

Transmission of Eastern Equine Encephalomyelitis Virus in Central Alabama

The American Journal of Tropical Medicine and Hygiene. Apr, 2003  |  Pubmed ID: 12875303

A site near Tuskegee, Alabama was examined for vector activity of eastern equine encephalomyelitis (EEE) virus in 2001. More than 23,000 mosquitoes representing 8 genera and 34 species were collected during a 21-week period, and five species, Culiseta melanura, Aedes vexans, Coquillettidia perturbans, Culex erraticus, and Uranotaenia sapphirina, were examined for the presence of virus using a nested reverse transcriptase-polymerase chain reaction for EEE virus. Each species was infected at various times of the mosquito season (May-September) with different minimum infection rates (MIRs). Culiseta melanura had the highest MIR (20.2) and positive pools were detected from late May to mid-September. Aedes vexans had an MIR of 2.2 and was infected early in the season (June), while Cq. perturbans exhibited a much higher field infection rate (9.9) with all positive pools collected in August. Culiseta melanura is a likely endemic vector in central Alabama, while Ae. vexans and Cq. perturbans probably function as bridge vectors. Culex erraticus, the most common mosquito in the habitat (54% of total collections), had an MIR of 3.2, and was persistently infected from mid-June to mid-September. This is the first report of high rates of EEE virus infection in this species, a member of the tropical subgenus Melanoconion. Uranotaenia sapphirina, considered to feed on amphibians and possibly reptiles, had an MIR of 5.6, with positive pools spanning a four-month period. This suggests that species other than birds may serve as a reservoir for EEE in hardwood swamps in the Southeastern United States and elsewhere. The lengthy period of mosquito infection with EEE virus, coupled with the diverse habits of the vectors and their proximity to a population center, indicate the importance of monitoring EEE virus activity in the Mid-South.

Effect of Transient Embryonic in Vivo Exposure to the Endocrine Disruptor Methoxychlor on Embryonic and Postnatal Testis Development

Journal of Andrology. Sep-Oct, 2003  |  Pubmed ID: 12954667

The current study was designed to examine the effects of a transient embryonic exposure to the pesticide methoxychlor, an endocrine disruptor, on in vivo rat testis development and function. Gestating female rats were transiently administered methoxychlor (MXC) from embryonic day 7 (E7; EO = plug date) through E15. Embryonic testes were collected at E16 and postnatal (PO = day of birth) testes at P4, P10, P17-20, and P60. Seminiferous cords formed in testes from MXC exposed males. However, at E16, there was a decrease in the area of cords and an increase in interstitial area in MXC exposed testes when compared with controls. At all postnatal ages collected, there did not appear to be differences in seminiferous cord/tubule area, interstitial area, or number of seminiferous cords/tubules between untreated controls and males exposed to MXC. Exposure to the endocrine disruptor also had no effect on the postnatal organ weights of a variety of different organs, nor were testosterone levels altered. Interestingly, there were reductions in the number of germ cells in testes from MXC-exposed males at P17-P20 when compared with untreated controls. Furthermore, there was a twofold increase in apoptotic cells in tubules from pubertal P17-P20-MXC exposed males when compared with untreated controls. Testes were collected from adult P60 males to determine if early embryonic and postnatal alterations in germ cell numbers or testis cellular composition had compromised spermatogenesis. In adult P60 MXC exposed testes there were no gross morphological changes in testis structure or cellular composition over that of controls. However, there was an increase in apoptotic cell number in elongating spermatids in MXC exposed testes. Four P60 males that were exposed to MXC during gestation and 4 control males were bred with unexposed females to determine their ability to produce offspring. All MXC exposed males were capable of impregnating females and had normal litter size and pup weights. Combined observations demonstrated that exposure to MXC during gestation at a critical stage of testis development (ie, sex determination) affects embryonic testis cellular composition, germ cell numbers, and germ cell survival. While alterations in these parameters does not affect the ability of males to produce offspring, there appears to be a reduced spermatogenic capacity associated with MXC treatment. Therefore, transient embryonic exposure to an endocrine disruptor (methoxychlor) during gestation can influence the germline and fertility in adult males.

Teleotolaryngology: a Retrospective Review at a Military Tertiary Treatment Facility

Otolaryngology--head and Neck Surgery : Official Journal of American Academy of Otolaryngology-Head and Neck Surgery. May, 2004  |  Pubmed ID: 15138414

The use of real-time telemedicine in providing quality health-care in multiple specialties has been demonstrated in several small studies; however, a review of the literature reveals no large-scale prospective or retrospective telemedicine studies in otolaryngology. The telemedicine office at Naval Medical Center San Diego (NMCSD) acquired a large otolaryngology telemedicine patient database, and this study reviews the otolaryngology telemedicine experience at NMCSD over an 18-month period.

Evaluation of a Recombinant Salivary Gland Protein (thrombostasin) As a Vaccine Candidate to Disrupt Blood-feeding by Horn Flies

Vaccine. Jun, 2004  |  Pubmed ID: 15149788

The potential for controlling blood-feeding by the cattle pest, Haematobia irritans irritans (horn fly), was tested by vaccination against thrombostasin (TS), an inhibitor of mammalian thrombin that is released into skin during horn fly blood-feeding. The increase in blood meal size that occurred for flies feeding on sensitized non-vaccinated hosts was blocked and egg development in female flies was delayed when horn flies fed on rabbits and cattle immunized with recombinant TS. This demonstration of the impact of disrupting TS action by vaccination provides a novel approach toward control of this veterinary pest and offers a paradigm for limiting blood-feeding in other medically-important insect species.

Insecticide Resistance and Cross-resistance in Alabama and Florida Strains of Culex Quinquefasciatus [correction]

Journal of Medical Entomology. May, 2004  |  Pubmed ID: 15185942

Insecticide resistance and cross-resistance was determined for three strains of Culex quinquefasciatus Say in the southeastern United States. HAmCq and MAmCq strains were collected in 2002 from Huntsville and Mobile, AL. The VBFmCq strain was collected in 1998 from Vero Beach, FL. VBFmCq, HAmCq, and MAmCq larvae showed resistance to permethrin with resistance ratios of 13, 100, and 940, respectively, compared with the susceptible S-Lab strain. Levels of resistance in HAmCq and MAmCq larvae were 200- and 830-fold to resmethrin and 4- and 70-fold to malathion, respectively. VBFmCq, HAmCq, and MAmCq strains all demonstrated a great ability to develop tolerance and/or cross-resistance to different insecticides, including deltamethrin (50-, 100-, and 300-fold), chlorpyrifos (150-, 33-, and 720-fold), fipronil (10-, 5-, and 15-fold), and imidacloprid (7.5-, 5- and 10-fold, respectively). Comparison of resistance ratios for pyrethroids, organophosphates, and imidacloprid at LC50 and LC90 and gradual slopes of dose-response curves indicated that VBFmCq, HAmCq, and MAmCq were heterozygous in response to these insecticides. All three strains showed high levels of susceptibility to Bacillus thuringiensis variety israelensis (Bti) and spinosad, although these mosquitoes had been extensively exposed to Bti. Thus, we conclude that Bti and spinosad may be valuable for the management of Cx. quinquefasciatus, especially in situations where local strains are highly resistant to other insecticides.

Mosquito and Arbovirus Activity During 1997-2002 in a Wetland in Northeastern Mississippi

Journal of Medical Entomology. May, 2004  |  Pubmed ID: 15185956

The species composition and population dynamics of adult mosquitoes in a wetland near Iuka, MS, were analyzed over a 6-yr period (1997-2002) and reverse transcription-polymerase chain reaction (PCR) detection rates of arboviruses determined during five of those years. Blood meals of three likely vector species were identified using a PCR-based method that allows identification of the host to species. Culex erraticus (Dyar & Knab) composed 51.9% of the population during the 6-yr period with 295 females collected per trap night. Eastern equine encephalomyelitis (EEE) virus was detected in six genera of mosquitoes [Coquillettidia perturbans (Walker), Culex restuans Theobald, Culex salinarius Coquillett, Culex erraticus (Dyar & Knab), Anopheles crucians Wiedemann, Anopheles quadrimaculatus Say, Aedes vexans (Meigen), Ochlerotatus triseriatus Say, and Psorophora ferox Humboldt) with positive pools occurring in 1998, 1999, and 2002. Culiseta melanura Coquillett occurred at a low level (< 1%) and was not infected. Saint Louis encephalitis virus was detected once in a single pool of Cx. erraticus in 1998. Neither West Nile virus nor LaCrosse virus was found. Minimum infection rates per 1000 females tested of competent vectors of EEE virus were variable and ranged from 0.14 for Cx. erraticus to 40.0 for Oc. triseriatus. Thirty-nine species of birds were identified in the focus with blood-engorged mosquitoes found to contain meals (n = 29) from eight avian species. The majority of meals was from the great blue heron, Ardea herodias L. (n = 55%), but when bird abundance data were adjusted for avian mass, the brown-headed cowbird, Molothrus ater (Boddaert); blue jay, Cyanocitta cristata (L.); and northern mockingbird, Mimus polyglottos (L.), were overrepresented as hosts.

Agroterrorism in the U.S.: Key Security Challenge for the 21st Century

Biosecurity and Bioterrorism : Biodefense Strategy, Practice, and Science. 2004  |  Pubmed ID: 15225403

Agriculture is one of the easiest sectors of the U.S. economy to disrupt, and its disruption could have catastrophic consequences for the U.S. and world economies. Agriculture in the U.S. accounts for 13% of the current Gross Domestic Product (GDP) and provides employment for 15% of the population. It produces high-quality, cheap, plentiful food for domestic consumption and accounts for more than $50 billion in exports. The likelihood of terrorist acts interrupting the production, processing, and distribution of agricultural products is high: A number of different possible plant or animal pathogens could cause harm or loss of production, and even an act of agroterrorism that did not result in the destruction of foodstuffs or interruptions in the food supply could have a psychological impact. A number of recent unintentional events and epidemics have prompted the U.S. and other countries to provide resources to counteract contagious diseases and contain their impact, including increased funding to federal agencies that are responsible for protecting domestic agriculture. This article presents recommendations to protect agriculture, including changing the way agriculture is viewed on the federal level and increasing the resources to protect agriculture from terrorist attack.

Identification of Reptilian and Amphibian Blood Meals from Mosquitoes in an Eastern Equine Encephalomyelitis Virus Focus in Central Alabama

The American Journal of Tropical Medicine and Hygiene. Sep, 2004  |  Pubmed ID: 15381805

Uranotaenia sapphirina, Culex erraticus, and Cx. peccator were collected in an enzootic eastern equine encephalomyelitis (EEE) virus focus in central Alabama (Tuskegee National Forest) from 2001 to 2003 and analyzed for virus as well as host selection. EEE virus was detected in each species every year except 2003, when pools of Cx. peccator were negative. Most (97%) of the 130 Cx. peccator blood meals identified were from ectothermic hosts; 3% were from birds. Among blood meals from reptiles (approximately 75% of the total), 81% were from Agkistrodon piscivorus (cottonmouth); all amphibian blood meals (approximately 25%) were from Rana spp. with > 50% taken from the bullfrog R. catesbeiana. Host identifications were made from 131 of 197 Cx. erraticus, but only 3 (2%) were derived from ectothermic species. Identification of Ur. sapphirina blood meals proved difficult and only 2 of 35 hosts were determined. Both were from R. catesbeiana. Ectothermic species are possible EEE virus reservoirs in the southeastern United States where species such as Cx. peccator and Ur. sapphirina occur with large, diverse reptilian, amphibian, and avian populations such as those at the Tuskegee site.

Insecticide Resistance in Alabama and Florida Mosquito Strains of Aedes Albopictus

Journal of Medical Entomology. Sep, 2004  |  Pubmed ID: 15535626

The susceptibility of four strains of Aedes albopictus (Skuse) to permethrin, deltamethrin, resmethrin, chlorpyrifos, malathion, propoxur, fipronil, imidacloprid, spinosad, and Bacillus thuringiensis variety israelensis (Bti) was determined. The HAmAal and MAmAal strains were collected in 2002 and 2003, respectively, from Huntsville and Mobile, AL, and the VBFmAal and SFmAal strains were collected in 1998 from Vero Beach and southern Florida, respectively. The HAmAal strain showed a 22-fold elevated level of resistance to deltamethrin compared with the susceptible Ikaken laboratory strain, whereas the VBFmAal strain showed a six-fold lower sensitivity to deltamethrin compared with Ikaken. However, comparison of resistance ratios for deltamethrin at LC50 and LC90 (21-fold) and the gradual slopes of dose-response curves indicated that the field population of this mosquito strain was heterogenous in response to deltamethrin. All four mosquito strains showed elevated levels of resistance to chlorpyrifos, with resistance ratios from 10 to 33. Nevertheless, except for the relatively low resistance to deltamethrin and chlorpyrifos, all mosquito strains showed a similar susceptibility or lower tolerance to the remaining insecticides tested compared with the susceptible Ikaken strain, even though some, such as permethrin, resmethrin, malathion, and Bti, have been used in the field for a long time, especially in Alabama. These results indicate that the development of resistance to insecticides in Ae. albopictus is slow and conventional insecticides, such as permethrin, resmethrin, malathion, and Bti, and relatively new insecticides, such as fipronil, imidacloprid, and spinosad, may all be valuable for the management of this important mosquito.

Fatty Acid-albumin Complexes and the Determination of the Transport of Long Chain Free Fatty Acids Across Membranes

Biochemistry. Apr, 2004  |  Pubmed ID: 15078093

Understanding the mechanism that governs the transport of long chain free fatty acids (FFA) across lipid bilayers is critical for understanding transport across cell membranes. Conflicting results have been reported for lipid vesicles; most investigators report that flip-flop occurs within the resolution time of the method (<5 ms) and that dissociation from the membrane is rate limiting, while other studies find that flip-flop is rate limiting and on the order of seconds. We have reinvestigated this problem and find that the methods used in studies reporting rapid flip-flop have not been interpreted correctly. We find that accurate information about transport of FFA across lipid vesicles requires that FFA be delivered to the vesicles as complexes with albumin (BSA). For example, we find that stopped-flow mixing of uncomplexed FFA with small unilamellar vesicles (SUV) containing pyranine yields the very fast influx rates reported previously (>100 s(-1)). However, these influx rates increase linearly with lipid vesicle concentration and can therefore not, as previously interpreted, represent flip-flop. In contrast, measurements of influx rates in SUV and giant unilamellar vesicles performed with oleate-BSA complexes reveal no dependence on vesicle concentration and yield influx rate constants of approximately 4 and approximately 0.5 s(-1), respectively. Rate constants for efflux and dissociation were determined from the transfer of oleate from vesicles to BSA and reveal similar influx and efflux but dissociation rate constants that are approximately 5-10-fold greater. We conclude that flip-flop is rate limiting for transport of FFA across lipid vesicles and slows with an increasing radius of curvature. These results, in contrast to those reporting that flip-flop is extremely fast, indicate that the lipid bilayer portion of biological membranes may present a significant barrier to transport of FFA across cell membranes.

Processing of Pro-thrombostasin by a Recombinant Subtilisin-like Proprotein Convertase Derived from the Salivary Glands of Horn Flies (Haematobia Irritans)

Insect Biochemistry and Molecular Biology. Dec, 2004  |  Pubmed ID: 15544942

Thrombostasin (TS) is a thrombin inhibitor found in the salivary glands of horn flies (Haematobia irritans). It is produced as an inactive form with a 76-amino acid propeptide in the N-terminus preceding the mature TS. A minimal recognition sequence by subtilisin-like proprotein convertases, Arg-Xaa-Xaa-Arg, is localized C-terminal to the propeptide. This study demonstrated that a gene cloned from the salivary glands of the horn fly encodes a new convertase, subsequently named horn fly proprotein convertase (HFPC), and that the recombinant HFPC expressed in insect HighFive cell culture specifically cleaves recombinant pro-thrombostasin, produced in E. coli, at the expected site. The relative cleavage efficiency of rHFPC was compared with that of recombinant human furin, a commercially available proprotein convertase. The result indicated that this newly identified proprotein convertase is of importance for the proteolytic maturation of thrombostasin, a protein secreted in horn fly saliva and used by the insect to counteract its host's haemostatic response.

The Effects of Long-term Community Level Treatment with Ivermectin (Mectizan) on Adult Onchocerca Volvulus in Latin America

The American Journal of Tropical Medicine and Hygiene. Nov, 2004  |  Pubmed ID: 15569792

The objective of this study was to examine nodules from Mexico, Guatemala, and Ecuador collected over a one-year period (2001) to determine the effects of semi-annual ivermectin treatments on Onchocerca volvulus macrofilarial populations. Nodules were sectioned, stained with hematoxylin and eosin, and histologic findings were compared between countries and with historical data prior to the introduction of ivermectin into the region. Nodules from Ecuador had 10 times more dead or moribund worms than the historical control (66.6% versus 6.5%); nodules from patients from Mexico and Guatemala did not differ from the control. More than 80% of the female worms in each country were uninseminated and producing unfertilized oocytes. Nodules containing males differed in each country from the historical control (P < 0.0001), with presence of males ranging from 19.7% in Mexico to 13.6% in Ecuador versus 73% in the control. Nodules with females producing active microfilariae ranged from 7.8% (Mexico) to 2.7% (Ecuador) versus 60% in the historical control (P < 0.0001). Nodules from Ecuador and Mexico were significantly smaller in size than those from Guatemala or historical controls (P < 0.0005). These results depict a deteriorating condition of adult O. volvulus populations in Mexico, Guatemala and Ecuador, indicating that semi-annual ivermectin treatment of >/=6 years has had a profound effect on survival and reproduction of this species.

Epigenetic Transgenerational Actions of Endocrine Disruptors and Male Fertility

Science (New York, N.Y.). Jun, 2005  |  Pubmed ID: 15933200

Transgenerational effects of environmental toxins require either a chromosomal or epigenetic alteration in the germ line. Transient exposure of a gestating female rat during the period of gonadal sex determination to the endocrine disruptors vinclozolin (an antiandrogenic compound) or methoxychlor (an estrogenic compound) induced an adult phenotype in the F1 generation of decreased spermatogenic capacity (cell number and viability) and increased incidence of male infertility. These effects were transferred through the male germ line to nearly all males of all subsequent generations examined (that is, F1 to F4). The effects on reproduction correlate with altered DNA methylation patterns in the germ line. The ability of an environmental factor (for example, endocrine disruptor) to reprogram the germ line and to promote a transgenerational disease state has significant implications for evolutionary biology and disease etiology.

A Clinical Comparison of Two Formulations of Tobramycin 0.3% Eyedrops in the Treatment of Acute Bacterial Conjunctivitis

European Journal of Ophthalmology. Sep-Oct, 2005  |  Pubmed ID: 16167284

To compare the safety and efficacy of a new enhanced viscosity ophthalmic formulation of tobramycin, given twice daily (BID), with the existing four times daily (QID) treatment regimen in patients with acute bacterial conjunctivitis.

Update: Guidelines for Defining the Legal Health Record For-disclosure Purposes

Journal of AHIMA / American Health Information Management Association. Sep, 2005  |  Pubmed ID: 16245584

In Vitro and in Vivo Potency of Moxifloxacin and Moxifloxacin Ophthalmic Solution 0.5%, a New Topical Fluoroquinolone

Survey of Ophthalmology. Nov, 2005  |  Pubmed ID: 16257308

Fluoroquinolones are a class of synthetic antibacterial agents that were approved for ocular therapy in 1991 and have become popular therapy for the treatment and prevention of various ocular infections. These agents are synthetic, broad-spectrum, rapidly bactericidal, and have good penetration into ocular tissues. Their main mechanism of action is the inhibition of bacterial enzymes needed for bacterial DNA synthesis. However, antibiotic resistance occurred swiftly to the earlier fluoroquinolones and better fluoroquinolones were needed. The fourth-generation fluoroquinolones, such as moxifloxacin and gatifloxacin, have enhanced activity against gram-positive bacteria while retaining potent activity against most gram-negative bacteria. These fourth-generation fluoroquinolones have improved penetration into the anterior chamber and have also demonstrated increased in vivo efficacy in several animal models of ocular infections. In addition, topical ophthalmic antibiotic products can deliver antibiotic concentrations directly to the eye that are thousands of times higher than their MICs. This article reviews published data describing the in vitro potency of moxifloxacin and its in vivo activity for treating and preventing experimental ocular infections.

Short Report: Impact of Ivermectin Community-level Treatments on Elimination of Adult Onchocerca Volvulus when Individuals Receive Multiple Treatments Per Year

The American Journal of Tropical Medicine and Hygiene. Dec, 2005  |  Pubmed ID: 16354830

A reanalysis of several published reports indicates that when community-wide biannual treatment disrupts transmission of new infection, a profound macrofilaricidal effect of ivermectin (Mectizan) occurs that is accelerated for individuals treated 4 times a year (4x/yr). The effect is particularly obvious on adult male worms and suggests that this gender is susceptible to repetitive treatment after transmission has been blocked or greatly reduced as a result of community treatment.

Chromosomal Localization of Two Antihemostatic Salivary Factors in Simulium Vittatum (Diptera: Simuliidae)

Journal of Medical Entomology. Sep, 2005  |  Pubmed ID: 16363163

The chromosomal locations of two genes encoding the salivary protein products Simulidin (SVAT) and Simulium vittatum erythyma protein (SVEP) were identified using high-resolution cytogenetic mapping. Chromosomal subsection levels were determined from larval and adult salivary gland polytene chromosomes and adult Malphigian tubule chromosomes. Syntenic relationships occurred for both loci from a wild population of Simulium vittatum IIIL-1 collected in central Alabama and the colonized IS-7 S. vittatum sibling. cSVAT mapped to the short arm of chromosomes III, IIIS-72a4.5 and cSVEP mapped to the long arm of chromosome III, IIIL-96b1. cSVAT sits proximal to a common IIIS-2 paracentric inversion, which occurs predominately as the standard sequence in the IIIL-1 sibling and as the inverted sequence in the IS-7 sibling. cSVEP sits close to the differentiated X chromosomes in the IIIL-1 sibling.

Regulation of Cementoblast Gene Expression by Inorganic Phosphate in Vitro

Calcified Tissue International. Feb, 2006  |  Pubmed ID: 16467974

Examination of mutant and knockout phenotypes with altered phosphate/pyrophosphate distribution has demonstrated that cementum, the mineralized tissue that sheathes the tooth root, is very sensitive to local levels of phosphate and pyrophosphate. The aim of this study was to examine the potential regulation of cementoblast cell behavior by inorganic phosphate (P(i)). Immortalized murine cementoblasts were treated with P(i) in vitro, and effects on gene expression (by quantitative real-time reverse-transcriptase polymerase chain reaction [RT-PCR]) and cell proliferation (by hemacytometer count) were observed. Dose-response (0.1-10 mM) and time-course (1-48 hours) assays were performed, as well as studies including the Na-P(i) uptake inhibitor phosphonoformic acid. Real-time RT-PCR indicated regulation by phosphate of several genes associated with differentiation/mineralization. A dose of 5 mM P(i) upregulated genes including the SIBLING family genes osteopontin (Opn, >300% of control) and dentin matrix protein-1 (Dmp-1, >3,000% of control). Another SIBLING family member, bone sialoprotein (Bsp), was downregulated, as were osteocalcin (Ocn) and type I collagen (Col1). Time-course experiments indicated that these genes responded within 6-24 hours. Time-course experiments also indicated rapid regulation (by 6 hours) of genes concerned with phosphate/pyrophosphate homeostasis, including the mouse progressive ankylosis gene (Ank), plasma cell membrane glycoprotein-1 (Pc-1), tissue nonspecific alkaline phosphatase (Tnap), and the Pit1 Na-P(i) cotransporter. Phosphate effects on cementoblasts were further shown to be uptake-dependent and proliferation-independent. These data suggest regulation by phosphate of multiple genes in cementoblasts in vitro. During formation, phosphate and pyrophosphate may be important regulators of cementoblast functions including maturation and regulation of matrix mineralization.

A Dynamic Transmission Model of Eastern Equine Encephalitis Virus

Ecological Modelling. Feb, 2006  |  Pubmed ID: 16501661

Eastern equine encephalitis virus (EEEV) is one of several arthropod-borne viruses (arboviruses) endemic to the United States. Interactions between arthropod (mosquito) vectors and avian amplification host populations play a significant role in the dynamics of arboviral transmission. Recent data have suggested the hypothesis that an increased rate of successful feeding on young-of-the-year (YOY) birds might play a role in the dynamics of EEEV transmission. To test this hypothesis, we developed a model to explore the effect of the interactions of the vectors and avian host populations on EEEV transmission. Sensitivity analyses conducted using this model revealed eleven parameters that were capable of disproportionately affecting the predicted level of EEEV infection in the vertebrate reservoir and vector populations. Of these, four parameters were related to the interaction of the vector with young-of-the-year birds. Furthermore, adult birds could not substitute for young-of-the-year in initiating and maintaining a predicted enzootic outbreak of EEEV. Taken together, the model predicted that young-of-the-year birds play a key role in establishing and maintaining enzootic outbreaks of EEEV.

Vascular Endothelial Growth Factor and Kinase Domain Region Receptor Are Involved in Both Seminiferous Cord Formation and Vascular Development During Testis Morphogenesis in the Rat

Biology of Reproduction. Jul, 2006  |  Pubmed ID: 16672722

Morphological male sex determination is dependent on migration of endothelial and preperitubular cells from the adjacent mesonephros into the developing testis. Our hypothesis is that VEGFA and its receptor KDR are necessary for both testicular cord formation and neovascularization. The Vegfa gene has 8 exons with many splice variants. Vegfa120, Vegfa164, and Vegfa188 mRNA isoforms were detected on Embryonic Day (E) 13.5 (plug date=E0) in the rat. Vegfa120, Vegfa144, Vegfa164, Vegfa188, and Vegfa205 mRNA were detected at E18 and Postnatal Day 3 (P3). Kdr mRNA was present on E13.5, whereas Fms-like tyrosine kinase 1 receptor (Flt1) mRNA was not detected until E18. VEGFA protein was localized to Sertoli cells at cord formation and KDR to germ and interstitial cells. The VEGFA signaling inhibitors SU1498 (40 microM) and VEGFR-TKI (8 microM) inhibited cord formation in E13 testis cultures with 90% reduced vascular density (P<0.01) in VEGFR-TKI-treated organs. Furthermore, Je-11 (10 microM), an antagonist to VEGFA, also perturbed cord formation and inhibited vascular density by more than 50% (P<0.01). To determine signal transduction pathways involved in VEGFA's regulation of testis morphogenesis, E13 testis were treated with LY 294002 (15 microM), a phosphoinositide 3-kinase (PI3K) pathway inhibitor, resulting in inhibition of both vascular density (46%) and cord formation. Thus, we support our hypothesis and conclude that VEGFA, secreted by the Sertoli cell, is involved in both neovascularization and cord formation and potentially acts through the PI3K pathway during testis morphogenesis to elicit its effects.

Different Mechanisms of Free Fatty Acid Flip-flop and Dissociation Revealed by Temperature and Molecular Species Dependence of Transport Across Lipid Vesicles

The Journal of Biological Chemistry. Jul, 2006  |  Pubmed ID: 16737957

The mechanism of free fatty acid (FFA) transport across membranes is a subject of intense investigation. We have demonstrated recently that flip-flop is the rate-limiting step for transport of oleic acid across phospholipid vesicles (Cupp, D., Kampf, J. P., and Kleinfeld, A. M. (2004) Biochemistry 43, 4473-4481). To better understand the nature of the flip-flop barrier, we measured the temperature dependence of a series of saturated and monounsaturated FFA. We determined the rate constants for flip-flop and dissociation for small (SUV), large (LUV), and giant (GUV) unilamellar vesicles composed of egg phosphatidylcholine. For all FFA and vesicle types, dissociation was faster than flip-flop, and for all FFA, flip-flop and dissociation were faster in SUV than in LUV or GUV. Rate constants for both flip-flop and dissociation decreased exponentially with increasing FFA size. However, only the flip-flop rate constants increased significantly with temperature; the barrier to flip-flop was virtually entirely due to an enthalpic activation free energy. The barrier to dissociation was primarily entropic. Analysis in terms of a simple free volume (V(f)) model revealed V(f) values for flip-flop that ranged between approximately 12 and 15 Angstroms(3), with larger values for SUV than for LUV or GUV. V(f) values increased with temperature, and this temperature dependence generated the enthalpic barrier to flip-flop. The barrier for dissociation and its size dependence primarily reflect the aqueous solubility of FFA. These are the first results to distinguish the energetics of flipflop and dissociation. This should lead to a better understanding of the mechanisms governing FFA transport across biological membranes.

A Prospective Evaluation of the WeeFIM in Patients with Cerebral Palsy Undergoing Orthopaedic Surgery

Journal of Pediatric Orthopedics. Jul-Aug, 2006  |  Pubmed ID: 16791077

Although frequently used in pediatric rehabilitation settings, the WeeFIM has not been tested in surgical pediatric orthopaedic patients.

Using Community Ties to Facilitate School-based Prevention Research

Health Promotion Practice. Oct, 2006  |  Pubmed ID: 16840771

One of the greatest obstacles to conducting school-based HIV/STD/pregnancy prevention research with adolescents is the reluctance of administrators or site-based decision-making councils to commit their teachers and students to participation in a project designed and managed by an outside group of researchers. A major concern is that researchers may not understand or agree with community sensitivities about such personal topics. By first establishing a collaborative relationship with health district educators currently working in Appalachian schools and residing in those communities, one finds a distinct advantage in terms of gaining admittance to area schools. The presence of local health educators at formative meetings also alloys many concerns of community members, as they view these local participants as monitors of outsider research efforts, thereby protecting the community culture from undue outside influence. During the course of the current study, health educators found they also learned more about their communities and about HIV prevention.

Efficacy of an American Alcohol and HIV Prevention Curriculum Adapted for Use in South Africa: Results of a Pilot Study in Five Township Schools

AIDS Education and Prevention : Official Publication of the International Society for AIDS Education. Aug, 2006  |  Pubmed ID: 16961447

The high prevalence of HIV among young people in African countries underscores a pressing need for effective prevention interventions. Adapting school-based prevention programs developed in the United States for use in African schools may present an alternative to the time-consuming process of developing home-grown programs. The researchers report the results of a pretest-posttest field trial of an alcohol/HIV prevention curriculum adapted from an American model and delivered to ninth-grade students in five South African township schools. The revised intervention was based primarily on the Project Northland alcohol prevention and Reducing the Risk safer sex programs. The researchers found significant differences in change from baseline to follow-up between students in intervention and comparison groups on intentions to use a condom; drinking before or during sex; and, among females, sex refusal self-efficacy. The results of the field trial suggest that behavioral interventions developed in Western countries may be rapidly adapted to work in other cultural contexts.

West Nile Virus Infection in Mosquitoes in the Mid-south USA, 2002-2005

Journal of Medical Entomology. Jan, 2007  |  Pubmed ID: 17294929

West Nile virus (family Flaviviridae, genus Flavivirus, WNV) was first detected in the Tennessee Valley and in Alabama in August 2001. In summer 2002, intensive viral activity was seen, but in subsequent years, viral activity settled into an enzootic pattern. Here, we report an analysis of viral activity in the mosquito fauna in the Mid-South from 2002 (the first year viral activity was detected in mosquitoes) through 2005. Eight mosquito species were infected with WNV during 2002. However, viral activity was only detected in four species--Culex salinarius Coquillett, Culex erraticus Dyar & Knab, Coquillettidia perturbans Walker, and Aedes vexans Meigen--in multiple years. The greatest number of positive pools was in Cx. erraticus and Cx. salinarius. Despite being specifically targeted for collection, Aedes albopictus Skuse was only found to be infected during the epiornitic year (2002), suggesting that under enzootic transmission conditions its role as a bridge vector in the region may not be significant. Virus-positive pools of Cx. erraticus were identified from winter-resting and early season dry ice-baited trap collections in 2005, implicating this species in WNV overwintering in Alabama. Molecular analysis of individuals initially identified as members of the Culex pipiens L. complex suggested that alleles characteristic of Cx. pipiens predominated in mosquitoes collected in Huntsville, AL, whereas alleles in the Auburn, AL, population were predominately characteristic of Culex quinquefaciatus Say. The southern boundary of the overlap zone of the two species seems to be located primarily between Huntsville and Auburn, a distance of 350 km.

The Effects of a Computer-based Pregnancy, STD, and HIV Prevention Intervention: a Nine-school Trial

Health Communication. 2007  |  Pubmed ID: 17523857

A computer-based intervention was designed to change perceived threat, perceived efficacy, attitudes, and knowledge regarding pregnancy, STD, and HIV prevention in rural adolescents. The intervention, which was guided largely by the extended parallel process model (Witte, 1992), was implemented and evaluated in nine rural high schools using an institutional cycle pretest-posttest control-group design (Campbell & Stanley, 1963; Cook & Campbell, 1979). Eight-hundred eighty-seven ninth-graders completed the survey at both points in time. Process evaluation results indicated that the intervention was implemented as intended, and that over 91% of students in the treatment group completed at least one of the six computer-based activities (M = 3.46, SD = 1.44 for those doing at least one activity). Two-way mixed-model repeated-measures analysis of variance revealed that students in the treatment group outperformed students in the control group on knowledge, condom self-efficacy, attitude toward waiting to have sex, and perceived susceptibility to HIV. These results suggest that computer-based programs may be a cost-effective and easily replicable means of providing teens with basic information and skills necessary to prevent pregnancy, STDs, and HIV.

Utilization of Dried Distillers Grains for Developing Beef Heifers

Journal of Animal Science. Sep, 2007  |  Pubmed ID: 17526658

A 2-yr study was conducted at 2 locations to determine if supplementing beef heifers with dried distillers grains (DDG) as an energy source affected growth or reproduction. Spring-born crossbred heifers (n = 316) were blocked by age or sire and age and assigned randomly to DDG or control (dried corn gluten feed, whole corn germ, urea) supplement. Heifers received prairie hay in amounts sufficient for ad libitum intake and 0.59% of BW DDG or 0.78% of BW control supplement (DM basis). Supplements were formulated to be isocaloric, but protein degradability differed. Supplemental undegradable intake protein intake from DDG averaged 267 g/animal daily and reached 318 g/animal daily; control supplemental undegradable intake protein intake averaged 90 g/animal daily and peaked at 107 g/animal daily. Initial pubertal status was determined by 2 blood samples collected 10 d apart, and monthly BW were collected from November through January; then biweekly BW and blood samples were collected from February until May yearly. Heifers were synchronized with 2 injections of PGF2alpha 14 d apart; estrus was detected and heifers were artificially inseminated for 5 d and placed with bulls 10 d later. Conception and pregnancy rates were determined via transrectal ultrasonography. Initial age, BW, and BCS did not differ (P > 0.92) for control and DDG heifers. Final BW, ADG, and final BCS also were not affected (P > 0.31) by supplementation. Estimated age and BW at puberty did not differ (P > 0.23) between treatments, and the proportions of pubertal heifers did not differ at the initiation of the experiment (P > 0.82), at the beginning of the 14-d sampling intervals, or before synchronization. Estrus synchronization rate (75.9%), time of estrus, and overall pregnancy rate (89.5%) were not affected (P > 0.14) by treatment. However, a greater proportion (P = 0.008) of DDG than control heifers conceived to AI (75.0 vs. 52.9%), resulting in greater (P = 0.07) AI pregnancy rates for DDG heifers (57.0 vs. 40.1%). Body weight or BCS at pregnancy diagnosis did not differ (P > 0.52) between DDG and control heifers. Supplementing beef heifers with DDG during development did not affect age at puberty but improved AI conception and pregnancy rates compared with an isocaloric control supplement.

Translocation and Expression of CSF1 in Pigmented Villonodular Synovitis, Tenosynovial Giant Cell Tumor, Rheumatoid Arthritis and Other Reactive Synovitides

The American Journal of Surgical Pathology. Jun, 2007  |  Pubmed ID: 17527089

We recently demonstrated that CSF1, the ligand of the tyrosine kinase receptor, CSF1R, can be translocated in pigmented villonodular synovitis (PVNS) and tenosynovial giant cell tumor (TGCT). In this study, we evaluated the staining characteristics of PVNS/TGCT and reactive synovitides for CSF1 and CSF1R by in situ hybridization and immunohistochemistry on tissue microarrays and correlated these findings with the recently described translocation. We collected specimens of TGCT/PVNS from 60 patients and of rheumatoid arthritis and other reactive synovitides from 74 patients. We identify 2 groups of PVNS and TGCT cases by the presence of CSF1 translocation and CSF1 expression. The first group (35 of 57 cases; 61%) had both the CSF1 translocation and high expression of CSF1 RNA, confirming our previous findings. Interestingly, a second group (22 of 57 cases; 39%) was identified that showed high expression of CSF1 RNA or CSF1 protein but did not have the translocation. The rheumatoid arthritis and reactive synovitis specimens showed localization of CSF1 RNA and protein to the synovial lining cells, implying a possible role for CSF1 in the pathogenesis of these lesions. As the CSF1 translocation is postulated to play an important role in the biology of PVNS/TGCT, the consistent presence of CSF1 expression in translocation-negative cases implies that other mechanisms can lead to CSF1 up-regulation. The consistent presence of CSF1 overexpression in all cases of PVNS/TGCT and reactive synovitides suggests both an important role for CSF1 in the spectrum of synovial pathologies and the possibility of targeting the CSF1/CSF1R interaction therapeutically.

Tonsillectomy in the Anticoagulated Patient

The Annals of Otology, Rhinology, and Laryngology. Aug, 2007  |  Pubmed ID: 17847726

The objectives of this study were to review perioperative bridging strategies for anticoagulated patients and to describe a novel bridging strategy for tonsillectomy in an anticoagulated patient that addresses both primary and secondary hemorrhage risks.

Lymphoplasmacytic Lymphoma Arising in the Setting of Hepatitis C and Mixed Cryoglobulinemia

Journal of Clinical Oncology : Official Journal of the American Society of Clinical Oncology. Sep, 2007  |  Pubmed ID: 17878484

Longitudinal Test of a Multiple Domain Model of Adolescent Condom Use

Journal of Sex Research. Nov, 2007  |  Pubmed ID: 18321017

A comprehensive multiple domain model (MDM) to understand condom use in adolescents was proposed and tested using structural equation modeling of data at three time points. The proposed model integrates social psychological theory, demographic and personality factors, social environment, and situational/contextual variables. Adolescents who were sexually active at time 2 (6 months after baseline) and time 3 (1 year after time 2) and completed surveys at all three time points were included in the analyses (N = 511). An iterative process of model testing resulted in a structural equation model that provided a good fit to the data (CFI = .92, RMSEA = .04). Models comparing gender and race as moderators also were calculated and supported the generalizability of the model. Results provide support for an MDM that goes beyond traditional social psychological models for a broader understanding of condom use in adolescents. Implications for further theory testing and safer sexual interventions are discussed.

Efficacy of Ivermectin Against Onchocerca Volvulus in Ghana

Lancet. Sep, 2007  |  Pubmed ID: 17905155

Utilization of Soybeans or Corn Milling By-products in Beef Heifer Development Diets

Journal of Animal Science. Feb, 2008  |  Pubmed ID: 17940162

Whole raw soybeans (SB), wet corn gluten feed (WCGF), and corn dried distillers grains (DDG) are sources of protein in heifer development rations. The objectives of this study were to compare puberty status before synchronization of estrus, response to synchronization, and AI and final pregnancy rates in heifers developed on diets containing SB, WCGF, or DDG that were formulated to be similar in energy and CP. These ingredients vary substantially in fat content, which may affect reproductive performance. Rate of gain during the feeding period and post-AI performance were also compared. In a preliminary experiment, 104 crossbred heifers were fed diets containing either 1.25 kg of SB/d or 2.0 kg of WCGF/d for 110 d (DM basis), beginning at 10 mo of age. In Exp. 1, 100 crossbred heifers received either 1.25 kg of SB/d or 2.5 kg of WCGF/d from approximately 7 to 10 mo of age (91 d; 4 pens/diet), and then were fed 1.25 kg of SB/d for an additional 114 d (4 pens/diet). In Exp. 2, 1.25 kg of SB/d or 1.25 kg of DDG/d was fed to 100 crossbred heifers for 226 d, beginning at 6 mo of age (4 pens/diet). At approximately 13 mo of age, heifers were fed melengestrol acetate (0.5 mg/d) for 14 d, followed by an i.m. injection of PGF(2 alpha) (25 mg) 19 d later to synchronize estrus. Heifers (14 mo of age) received AI for 5 d after PGF(2 alpha), at which time the dietary treatments were ended. Heifers were commingled while grazing on native pasture and were exposed to bulls for approximately 60 d beginning 10 d after the last day of AI. Pregnancy to AI was determined by ultrasound 45 d after the last day of AI. Heifers fed SB in the preliminary experiment had a lower (P < 0.05) synchronization rate (81 vs. 96%) and longer interval (P = 0.05) from PGF(2 alpha) to estrus (76.6 vs. 69.2 h) compared with heifers fed WCGF. In Exp. 1, the age at which the heifers were begun on SB diets did not alter (P > 0.10) the synchronization rate (79%) or timing of estrus after PGF(2 alpha) (77.8 h). In Exp. 2, the synchronization rate (86%) and timing of estrus after PGF(2 alpha) (69.3 h) did not differ (P > 0.10) because of diet. No differences (P > 0.10) were due to diet for AI conception rates (overall mean for each experiment: 76.5, 60, and 68.5%), percentage of all heifers becoming pregnant to AI (67, 46, and 59%), or final pregnancy rates (92, 90, and 90%) in the preliminary experiment, Exp. 1, or Exp. 2, respectively. In summary, SB, DDG, and WCGF can be used as sources of protein in heifer development diets at the inclusion rates used in these studies.

A Proposed Role for VEGF Isoforms in Sex-specific Vasculature Development in the Gonad

Reproduction in Domestic Animals = Zuchthygiene. Jul, 2008  |  Pubmed ID: 18638140

Many scientists have expended efforts to determine what regulates development of an indifferent gonad into either a testis or ovary. Expression of Sry and upregulation of Sox9 are factors that initiate formation of the testis-specific pathway to allow for both sex-specific vasculature and seminiferous cord formation. Migration of mesonephric precursors of peritubular myoid cells and endothelial cells into the differentiating testis is a critical step in formation of both of these structures. Furthermore, these events appear to be initiated downstream from Sry expression. Sertoli cell secretion of growth factors acts to attract these mesonephric cells. One hypothesis is that a growth factor specific for these cell linages act in concert to coordinate migration of both peritubular and endothelial cells. A second hypothesis is that several growth factors stimulate migration and differentiation of mesonephric 'stem-like' cells to result in migration and differentiation into several different cell lineages. While the specific mechanism is unclear, several growth factors have been implicated in the initiation of mesonephric cell migration. This review will focus on the proposed mechanisms of a growth factor, Vascular Endothelial Growth Factor, and how different angiogenic and inhibitory isoforms from this single gene may aid in development of testis-specific vascular development.

Safety of Surgeon-directed Conscious Sedation in Nasal Surgery

Archives of Facial Plastic Surgery : Official Publication for the American Academy of Facial Plastic and Reconstructive Surgery, Inc. and the International Federation of Facial Plastic Surgery Societies. Jul-Aug, 2008  |  Pubmed ID: 18645099

Not So Innocuous

The American Journal of Medicine. Oct, 2008  |  Pubmed ID: 18823853

Executive Management Education in Health Care at a Naval Medical Center: a Descriptive Report

Military Medicine. Feb, 2008  |  Pubmed ID: 18333498

Resource constraints in a time of conflict place particular stress on military medicine, especially in view of demands for medical care due to injuries. Effective management of health care systems and resources is essential. Management education of clinical leaders therefore is an excellent investment of time and effort. This article describes a Master's of Public Health degree program customized to meet the needs of the naval health care system and facilitate active involvement of current employees.

Sexual Self-concept and Sexual Self-efficacy in Adolescents: a Possible Clue to Promoting Sexual Health?

Journal of Sex Research. Jul-Sep, 2008  |  Pubmed ID: 18686156

This study examined the associations between sexual self-concept (sexual esteem and sexual anxiety) and sexual self-efficacy (situational and resistive) in a sample of 388 high school students (59% Caucasian, 28% African American). Males reported lower sexual esteem and lower sexual self-efficacy than females. Males and African Americans reported higher levels of sexual anxiety and lower levels of resistive self-efficacy than females and Caucasians. In regression models, higher sexual self-esteem uniquely predicted higher sexual self-efficacy scores, even after controlling for demographic variables, knowledge of sexual risk, and previous coital experience. In post hoc analyses, sexual self-esteem mediated the relation between knowledge of sexual risk and both types of sexual self-efficacy. Results suggest the need for interventions to promote male sexual self-efficacy and sexual esteem and the need for longitudinal research that explicates models of sexual health in adolescence.

Tissue Effects After Stereotactic Body Radiotherapy Using Cyberknife for Patients with Abdominal Malignancies

Clinical Oncology (Royal College of Radiologists (Great Britain)). Feb, 2008  |  Pubmed ID: 17900882

To report the tissue effects of treatment with single fraction stereotactic body radiotherapy (SBRT) using Cyberknife on malignant tumours of the abdomen and adjacent normal organs.

Chromosomal Aberrations in a Case of Synchronous Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue Type and Bronchogenic Adenocarcinoma

Applied Immunohistochemistry & Molecular Morphology : AIMM / Official Publication of the Society for Applied Immunohistochemistry. May, 2008  |  Pubmed ID: 18301237

We present the chromosomal aberrations in a case of synchronous extranodal marginal zone B-cell lymphoma and bronchogenic adenocarcinoma with bronchioloalveolar features. Using fluorescence in situ hybridization, we identified deletion of the immunoglobulin heavy chain gene in the lymphomatous component, but not the carcinomatous component. The presence of differing genetic compositions suggests a biclonal environment composed of 2 distinct neoplastic processes.

Effects of a School-based, Theory-driven HIV and Pregnancy Prevention Curriculum

Perspectives on Sexual and Reproductive Health. Mar, 2008  |  Pubmed ID: 18318871

Although a number of interventions are effective at reducing risky adolescent sexual behavior, it may be possible to make them even more effective by addressing adolescents' approaches to risk-taking.

Genetic Deletion of JAM-C Reveals a Role in Myeloid Progenitor Generation

Blood. Feb, 2009  |  Pubmed ID: 19109565

Hematopoietic stem cells (HSCs) have the capacity to self-renew and continuously differentiate into all blood cell lineages throughout life. At each branching point during differentiation, interactions with the environment are key in the generation of daughter cells with distinct fates. Here, we examined the role of the cell adhesion molecule JAM-C, a protein known to mediate cellular polarity during spermatogenesis, in hematopoiesis. We show that murine JAM-C is highly expressed on HSCs in the bone marrow (BM). Expression correlates with self-renewal, the highest being on long-term repopulating HSCs, and decreases with differentiation, which is maintained longest among myeloid committed progenitors. Inclusion of JAM-C as a sole marker on lineage-negative BM cells yields HSC enrichments and long-term multilineage reconstitution when transferred to lethally irradiated mice. Analysis of Jam-C-deficient mice showed that two-thirds die within 48 hours after birth. In the surviving animals, loss of Jam-C leads to an increase in myeloid progenitors and granulocytes in the BM. Stem cells and myeloid cells from fetal liver are normal in number and homing to the BM. These results provide evidence that JAM-C defines HSCs in the BM and that JAM-C plays a role in controlling myeloid progenitor generation in the BM.

Evaluation of Antral Follicle Count and Ovarian Morphology in Crossbred Beef Cows: Investigation of Influence of Stage of the Estrous Cycle, Age, and Birth Weight

Journal of Animal Science. Jun, 2009  |  Pubmed ID: 19286826

Depletion of the ovarian reserve is associated with reproductive senescence in mammalian females, and there is a positive relationship between the size of the ovarian reserve and the number of antral follicles on the surface of the ovary. Therefore, we conducted a series of experiments to investigate the influence of stage of the estrous cycle, age, and birth weight on antral follicle counts (AFC) in beef cows and heifers. Pairs of ovaries were collected from crossbred beef cows at slaughter (n = 72) or at necropsy (n = 333; 0 to 11 yr of age); all visible antral follicles were counted, the ovaries were weighed, and stage of the estrous cycle was estimated based on ovarian morphology. There was no influence of estimated stage of the estrous cycle on AFC (P = 0.36). There was a small but positive effect of birth weight on AFC [AFC = -1.7 + 0.31(birth weight); P = 0.007, r(2) = 0.05]. When antral follicle counts were regressed on age, there was a quadratic effect of age such that AFC increased until 5 yr of age and decreased thereafter [AFC = 12.9 + 9.0(yr) - 0.86(yr(2)); P < 0.001, r(2) = 0.22]. In a third experiment, crossbred beef heifers (n = 406; 353 to 463 d of age) at 3 locations were subjected to ovarian ultrasonography on unknown day of the estrous cycle. Heifers were classified as low AFC (<15 follicle, n = 84) or high AFC (>24 follicles, n = 178). Whereas estimated stage of the estrous cycle did not influence AFC (P = 0.62), heifers classified as low AFC had smaller ovaries (P = 0.001), decreased birth weight (P = 0.003), and a decreased heifer pregnancy rate (P = 0.05) compared with heifers in the high AFC group. From these results, we conclude that AFC in beef cows and heifers is influenced by birth weight and age but not by stage of the estrous cycle. In beef cows, the number of antral follicles increases to 5 yr of age and then begins to decline. This may indicate that a decrease in fertility due to decline of the ovarian reserve may begin earlier than previously thought in beef cows.

Salivary Gland Thrombostasin Isoforms Differentially Regulate Blood Uptake of Horn Flies Fed on New Zealand White Rabbits

Journal of Medical Entomology. Mar, 2009  |  Pubmed ID: 19351087

Thrombostasin (TS) is a previously characterized anticlotting protein with multiple isoforms found in the saliva of horn flies. In this report, the effect of TS isoforms on blood feeding was assessed using individual flies that carried corresponding ts allelles. Laboratory studies of horn fly blood feeding were conducted using colony-reared flies fed on New Zealand White (NZW) rabbits. After timed 20-min feeding periods, each fly was characterized for gender, blood volume uptake, and ts genotype. The results showed that mean blood volumes obtained by individual flies were not related to fly gender but were correlated to the ts genotype(s) carried by each fly. A fly having one or both ts alleles coding for the TS9 isoform took less blood than those possessing one or both ts alleles coding for the TS10 isoform. These results confirm the significant role that TS plays in horn fly feeding and highlight the differential impact of TS protein isoforms that vary by as few as three amino acids.

Pregnancy During Otolaryngology Residency: Experience and Recommendations

The American Surgeon. May, 2009  |  Pubmed ID: 19445293

Pregnancy during graduate medical training became a pertinent issue in the United States during the 10-year interval between 1992 and 2002 as the number of female residents trended steadily upward to over 25 per cent. Surgical training programs characteristically present unique challenges and stressors for all trainees, and pregnancy introduces additional physical, professional, and emotional demands for the pregnant woman and her coworkers. A qualitative study was performed using in-person interviews of female otolaryngology residents who had given birth within the previous 12 months. Items addressed included the pregnancy course and its complications, specific stressors during and after pregnancy, and solutions implemented by the resident and her program director. Reactions and level of support from coworkers were also discussed. Five pregnancies were reported among three residents interviewed. One resident experienced preterm delivery, which necessitated a week-long stay in the neonatal intensive care unit for her infant. Another had chorioamnionitis during delivery of two infants. One child had low birth weight. The third resident had a miscarriage during the first trimester of her first pregnancy and sustained a minor head injury after fainting in the operating room during her second pregnancy. Overall, long hours, unpredictable work demands, and guilt over colleagues' increased workloads and altered schedules were noted as significant sources of stress among these residents; the women also described high expectations of themselves, along with misgivings over their ability to balance pregnancy and parenthood with career demands. The most significant postpartum stress indicator was the matter of child care, especially as it related to finding adequate coverage for on-call periods ranging from 3 to 14 days per month. Maintaining breastfeeding was an additional concern in the postpartum period. Pregnancy during surgical residency is a significant source of conflict for the pregnant resident and her colleagues. Our study illustrates how program directors can pre-emptively address challenges this event presents. When policies on maternity leave, call issues during pregnancy, and flexible rotation schedules are in place before pregnancy occurs, the process may be smoother and more rewarding for all involved.

Neutralization of Vascular Endothelial Growth Factor Antiangiogenic Isoforms is More Effective Than Treatment with Proangiogenic Isoforms in Stimulating Vascular Development and Follicle Progression in the Perinatal Rat Ovary

Biology of Reproduction. Nov, 2009  |  Pubmed ID: 19605786

Inhibition of vascular endothelial growth factor A (VEGFA) signal transduction arrests vascular and follicle development. Because antiangiogenic VEGFA isoforms are proposed to block proangiogenic VEGFA isoforms from binding to their receptors, we hypothesized that proangiogenic isoforms promote and antiangiogenic isoforms inhibit these processes. The antiangiogenic isoforms Vegfa_165b and Vegfa_189b were amplified and sequenced from rat ovaries. The Vegfa_165b sequence was 90% homologous to human VEGFA_165B. Quantitative RT-PCR determined that Vegfa_165b mRNA was more abundant around Embryonic Day 18, but Vegfa_189b lacked a distinct pattern of abundance. Antiangiogenic VEGFA isoforms were localized to pregranulosa and granulosa cells of all follicle stages and to theca cells of advanced-stage follicles. To determine the effects of VEGFA isoforms in developing ovaries, Postnatal Day 3/4 rat ovaries were cultured with VEGFA_164 or an antibody to antiangiogenic isoforms (anti-VEGFAxxxB). Treatment with 50 ng/ml of VEGFA_164 resulted in a 93% increase in vascular density (P < 0.01), and treated ovaries were composed of fewer primordial follicles (stage 0) and more developing follicles (stages 1-4) than controls (P < 0.04). Ovaries treated with 5 ng/ml of VEGFAxxxB antibody had a 93% increase in vascular density (P < 0.02), with fewer primordial and early primary follicles (stage 1) and more primary, transitional, and secondary follicles (stages 2, 3, and 4, respectively) compared with controls (P < 0.005). We conclude that neutralization of antiangiogenic VEGFA isoforms may be a more effective mechanism of enhancing vascular and follicular development in perinatal rat ovaries than treatment with the proangiogenic isoform VEGFA_164.

Cell Biology Symposium: the Role of MicroRNA in Cell Function

Journal of Animal Science. Apr, 2009  |  Pubmed ID: 18997082

Addition of Carbon-based Nucleophiles to Fmoc-protected Acyl Iminium Ions

The Journal of Organic Chemistry. May, 2009  |  Pubmed ID: 19366203

Weakly basic carbon nucleophiles add efficiently to a Fmoc-protected N,O-acetal compound. The new reactions highlight the compatibility of the Fmoc protecting group with moderately basic reaction conditions and should serve as a model for the development of more efficient syntheses of Fmoc-protected amino acids.

Bioethics and the Explosive Rise of Animal Law

The American Journal of Bioethics : AJOB. May, 2009  |  Pubmed ID: 19396669

Combined Targeting of BRAF and CRAF or BRAF and PI3K Effector Pathways is Required for Efficacy in NRAS Mutant Tumors

PloS One. 2009  |  Pubmed ID: 19492075

Oncogenic RAS is a highly validated cancer target. Attempts at targeting RAS directly have so far not succeeded in the clinic. Understanding downstream RAS-effectors that mediate oncogenesis in a RAS mutant setting will help tailor treatments that use RAS-effector inhibitors either alone or in combination to target RAS-driven tumors.

Inhibition of Vascular Endothelial Growth Factor Receptor Signal Transduction Blocks Follicle Progression but Does Not Necessarily Disrupt Vascular Development in Perinatal Rat Ovaries

Biology of Reproduction. Nov, 2009  |  Pubmed ID: 19605787

We hypothesized that vascular endothelial growth factor A (VEGFA) angiogenic isoforms and their receptors, FLT1 and KDR, regulate follicular progression in the perinatal rat ovary. Each VEGFA angiogenic isoform has unique functions (based on its exons) that affect diffusibility, cell migration, branching, and development of large vessels. The Vegfa angiogenic isoforms (Vegfa_120, Vegfa_164, and Vegfa_188) were detected in developing rat ovaries, and quantitative RT-PCR determined that Vegfa_120 and Vegfa_164 mRNA was more abundant after birth, while Vegfa_188 mRNA was highest at Embryonic Day 16. VEGFA and its receptors were localized to pregranulosa and granulosa cells of all follicle stages and to theca cells of advanced-stage follicles. To determine the role of VEGFA in developing ovaries, Postnatal Day 3/4 rat ovaries were cultured with 8 muM VEGFR-TKI, a tyrosine kinase inhibitor that blocks FLT1 and KDR. Ovaries treated with VEGFR-TKI had vascular development reduced by 94% (P < 0.0001), with more primordial follicles (stage 0), fewer early primary, transitional, and secondary follicles (stages 1, 3, and 4, respectively), and greater total follicle numbers compared with control ovaries (P < 0.005). V1, an inhibitor specific for KDR, was utilized to determine the effects of only KDR inhibition. Treatment with 30 muM V1 had no effect on vascular density; however, treated ovaries had fewer early primary, transitional, and secondary follicles and more primary follicles (stage 2) compared with control ovaries (P < 0.05). We conclude that VEGFA may be involved in primordial follicle activation and in follicle maturation and survival, which are regulated through vascular-dependent and vascular-independent mechanisms.

Beginning the Thai Family Matters Project: An Areal Analysis of Bad Neighborhoods and Adolescents' Problematic Behaviours in Thailand

Warasan Prachakon Lae Sangkhom = Journal of Population and Social Studies. Jul, 2009  |  Pubmed ID: 19823692

Under the Thai Family Matters program initiative, this study investigates an association between neighborhood characteristics and problematic behaviors including alcohol and drug use, and sexual and delinquent behaviors among Thai adolescents. Data were derived from 420 families whose children aged 13-14 were selected from 30,471 households enumerated and listed from 245 blocks in seven districts in Bangkok Metropolis including Min Buri, Pathum Wan, Bangkok Noi, Bang Kho Laem, Sai Mai, Wang Thonglang and Suan Luang. Probability Proportional to Size method (PPS) was used in the sample selection process. Interviews were conducted with one parent and one adolescent in each household. Areal analysis shows that adolescents' problematic behaviors are significantly related to the districts where they live as well as the bad neighborhood characteristics that they reported. The study confirmed that any micro - level family program to prevent or correct problematic behaviors of adolescents need to also take into account the macro - level approach to manage the difficult neighborhoods as well as to deal with the bad environment in the broader areas of Bangkok Metropolis where the adolescents live.

Comparing the Efficacy of Permanent Classroom Teachers to Temporary Health Educators for Pregnancy and HIV Prevention Instruction

Health Promotion Practice. Oct, 2009  |  Pubmed ID: 18381972

Ninth grade health education classrooms were randomly assigned to conditions in which a 14-lesson unit on HIV and pregnancy prevention was provided either by the permanent classroom teacher or by a temporary health educator. Student data were collected prior to the lessons and approximately 3 weeks after the completion of the unit. Results indicate that students who learned the unit from the classroom teacher reported that that the instructor was more likeable and credible and that the classrooms were more motivational. Sexually active adolescents with regular classroom teachers reported greater increases in frequency of class discussion.

KDR-LacZ-expressing Cells Are Involved in Ovarian and Testis-specific Vascular Development, Suggesting a Role for VEGFA in the Regulation of This Vasculature

Cell and Tissue Research. Oct, 2010  |  Pubmed ID: 20848132

Our objectives were to evaluate kinase insert domain protein receptor (KDR)-β-galactosidase (LacZ) expression as a marker for vascular development during gonadal morphogenesis and to determine whether any novel non-angiogenic KDR-LacZ expression was present in mouse testes or ovaries. Gonads were collected from mice expressing LacZ driven by the Kdr promoter (KDR-LacZ) from embryonic day 11 (E11) through postnatal day 60 (P60). At E11.5, mesonephric cells expressing KDR-LacZ seemed to migrate into the developing testis and surrounded developing seminiferous cords. Cells expressing KDR-LacZ appeared in the ovary with no apparent migration from the adjacent mesonephros, suggesting a different origin of endothelial cells. Testis organ cultures from E11 mice were treated with 8 μM VEGFR-TKI, a vascular endothelial growth factor A signal transduction inhibitor; subsequently, the amount of KDR-LacZ staining was reduced by 66%-99% (P<0.002), and the ability of KDR-expressing cells to form a densely organized vascular network was inhibited. Novel non-angiogenic KDR-LacZ staining was detected in the testis on specific subsets of germ cells at E16, E17, P4, P20, P30, and P60. In ovaries, staining was present on oocytes within oocyte cysts at E17 and within late secondary follicles of postnatal mice. Thus, KDR is an excellent marker for analyzing vascular development in the gonads. Inhibition of VEGFA signal transduction prevents the development of testis-specific vasculature. Furthermore, non-vascular KDR-LacZ staining suggests that KDR directly affects both spermatogenesis and somatic-oocyte interactions during gametogenesis.

Spirituality Within the Family and the Prevention of Health Risk Behavior Among Adolescents in Bangkok, Thailand

Social Science & Medicine (1982). Nov, 2010  |  Pubmed ID: 20926170

This study investigates the influences of a family's spiritual beliefs and practices on substance use and sexual risk behaviors among young adolescents 13-14 years old in Bangkok, Thailand. Independent predictor variables are the parents' and teens' spiritual beliefs and practices in Buddhism and parental monitoring behaviors. The study uses data from the 2007 Baseline Survey of the Thai Family Matters Project, which adapted a U.S. based family prevention program for Thai culture. A representative sample of 420 pairs of parents and teens from the Bangkok metropolitan area was recruited to participate in the study. Structural equation models indicate that positive direct and indirect associations of the spirituality of parents and teens within a family and the prevention of adolescent risk behaviors are significant and consistent.

The Excimer Laser Sheath Technique for Embedded Inferior Vena Cava Filter Removal

Journal of Vascular and Interventional Radiology : JVIR. Dec, 2010  |  Pubmed ID: 21050774

An inferior vena cava (IVC) filter became embedded within the IVC of a 45-year-old man after prolonged implantation. Because of incorporation of the filter legs within the caval endothelium, the filter was densely adherent and could not be sheathed using standard retrieval methods. In this patient, the authors performed percutaneous filter retrieval using an excimer laser sheath technique for circumferential ablation of dense fibrotic tissue between the filter and IVC. Endovascular laser ablation allowed facile separation of the filter from the IVC, without tearing of the tissues, and the filter was removed successfully without complication.

Caenorhabditis is a Metazoan Host for Legionella

Cellular Microbiology. Mar, 2010  |  Pubmed ID: 19863556

We investigated whether nematodes contribute to the persistence, differentiation and amplification of Legionella species in soil, an emerging source for Legionnaires' disease. Here we show that Legionella spp. colonize the intestinal tracts of Caenorhabditis nematodes leading to worm death. Susceptibility to Legionella is influenced by innate immune responses governed by the p38 mitogen-activated protein kinase and insulin/insulin growth factor-1 receptor signalling pathways. We also show that L. pneumophila colonizes the intestinal tract of nematodes cultivated in soil. To distinguish between transient infection and persistence, plate-fed and soil-extracted nematodes-fed fluorescent strains of L. pneumophila were analysed. Bacteria replicated within the nematode intestinal tract, did not invade surrounding tissue, and were excreted as differentiated forms that were transmitted to offspring. Interestingly, the ultrastructural features of the differentiated bacterial forms were similar to cyst-like forms observed within protozoa, amoeba and mammalian cell lines. While intestinal colonization of L. pneumophila dotA and icmT mutant strains did not alter the survival rate of nematodes in comparison to wild-type strains, nematodes colonized with the dot/icm mutant strains exhibited significantly increased levels of germline apoptosis. Taken together, these studies show that nematodes may serve as natural hosts for these organisms and thereby contribute to their dissemination in the environment and suggest that the remarkable ability of L. pneumophila to subvert host cell signalling and evade mammalian immune responses evolved through the natural selection associated with cycling between protozoan and metazoan hosts.

Effect of Dietary Crude Protein Source on Hormone and Follicle Characteristics in Beef Heifers

Journal of Animal Science. Mar, 2010  |  Pubmed ID: 19933430

Ground, raw soybeans (SB), or dried distillers grain plus solubles (DDGS) were utilized in heifer development diets to determine the effect of dietary fat and protein source on hormone and follicle characteristics and ADG. The experiment was conducted over 2 yr with 100 June-born heifers (199 +/- 2 kg initial BW, n = 50 per yr). The experimental periods were 157 and 207 d in yr 1 and 2, respectively. Heifers were provided a dietary supplement (DM basis) of 1.23 kg of SB and 0.40 kg of corn or 1.65 kg of DDGS between weaning and breeding. Estrus was synchronized with 2 injections of PGF(2alpha) 14 d apart. Dominant follicles were measured and aspirated via transvaginal ultrasonography 60 h after the second PGF(2alpha) injection. Heifers were exposed to bulls beginning 14 d after aspiration for 45 d. Heifer ADG was greater (P = 0.02) for DDGS heifers in yr 1, but was similar (P = 0.47) in yr 2. However, there was no difference (P = 0.35) in final BW in either year. There was no difference (P >or= 0.67) in follicle size, follicle hormone concentrations, or pregnancy rate (88%) between yr 1 and 2. Serum estrogen at 48 or 60 h after PGF(2alpha) injection were similar (P >or= 0.91); however, LH at 60 h in yr 2 tended to be greater (P = 0.07) for DDGS heifers. The percentage of heifers experiencing an LH surge 48 and 60 h after PGF(2alpha) injection was not affected (P >/= 0.40) by treatment. Calf production was not affected (P >or= 0.20) by developmental diet. In summary, DDGS and SB have similar effects on hormone and follicle characteristics at the inclusion rates used in these studies.

Developing GIS-based Eastern Equine Encephalitis Vector-host Models in Tuskegee, Alabama

International Journal of Health Geographics. 2010  |  Pubmed ID: 20181267

A site near Tuskegee, Alabama was examined for vector-host activities of eastern equine encephalomyelitis virus (EEEV). Land cover maps of the study site were created in ArcInfo 9.2 from QuickBird data encompassing visible and near-infrared (NIR) band information (0.45 to 0.72 microm) acquired July 15, 2008. Georeferenced mosquito and bird sampling sites, and their associated land cover attributes from the study site, were overlaid onto the satellite data. SAS 9.1.4 was used to explore univariate statistics and to generate regression models using the field and remote-sampled mosquito and bird data. Regression models indicated that Culex erracticus and Northern Cardinals were the most abundant mosquito and bird species, respectively. Spatial linear prediction models were then generated in Geostatistical Analyst Extension of ArcGIS 9.2. Additionally, a model of the study site was generated, based on a Digital Elevation Model (DEM), using ArcScene extension of ArcGIS 9.2.

Parenting and Adolescent Problem Behaviors: a Comparative Study of Sons and Daughters in Thailand

Journal of the Medical Association of Thailand = Chotmaihet Thangphaet. Mar, 2010  |  Pubmed ID: 20420103

Investigates parenting practices and the reported sexual and delinquent behaviors among Thai adolescents, by focusing on the difference between sons and daughters.

Neutralization of Vascular Endothelial Growth Factor Antiangiogenic Isoforms or Administration of Proangiogenic Isoforms Stimulates Vascular Development in the Rat Testis

Reproduction (Cambridge, England). Aug, 2010  |  Pubmed ID: 20457593

Vascular endothelial growth factor A (VEGFA) plays a role in both angiogenesis and seminiferous cord formation, and alternative splicing of the Vegfa gene produces both proangiogenic isoforms and antiangiogenic isoforms (B-isoforms). The objectives of this study were to evaluate the expression of pro- and antiangiogenic isoforms during testis development and to determine the role of VEGFA isoforms in testis morphogenesis. Quantitative RT-PCR determined that Vegfa_165b mRNA was most abundant between embryonic days 13.5 and 16 (E13.5 and 16; P<0.05). Compared with ovarian mRNA levels, Vegfa_120 was more abundant at E13-14 (P<0.05), Vegfa_164 was less abundant at E13 (P<0.05), and Vegfa_165b tended to be less abundant at E13 (P<0.09) in testes. Immunohistochemical staining localized antiangiogenic isoforms to subsets of germ cells at E14-16, and western blot analysis revealed similar protein levels for VEGFA_165B, VEGFA_189B, and VEGFA_206B at this time point. Treatment of E13 organ culture testes with VEGFA_120, VEGFA_164, and an antibody to antiangiogenic isoforms (anti-VEGFAxxxB) resulted in less organized and defined seminiferous cords compared with paired controls. In addition, 50 ng/ml VEGFA_120 and VEGFA_164 treatments increased vascular density in cultured testes by 60 and 48% respectively, and treatment with VEGFAxxxB antibody increased vascular density by 76% in testes (0.5 ng/ml) and 81% in ovaries (5 ng/ml) compared with controls (P<0.05). In conclusion, both pro- and antiangiogenic VEGFA isoforms are involved in the development of vasculature and seminiferous cords in rat testes, and differential expression of these isoforms may be important for normal gonadal development.

Mechanisms for Maintenance, Replication, and Repair of the Chloroplast Genome in Plants

Journal of Experimental Botany. Jun, 2010  |  Pubmed ID: 20513654

Improving Cost-effectiveness of Epidemiological Studies Via Designed Missingness Strategies

Statistics in Medicine. Jun, 2010  |  Pubmed ID: 20527011

Modern epidemiological studies face opportunities and challenges posed by an ever-expanding capacity to measure a wide range of environmental exposures, along with sophisticated biomarkers of exposure and response at the individual level. The challenge of deciding what to measure is further complicated for longitudinal studies, where logistical and cost constraints preclude the collection of all possible measurements on all participants at every follow-up time. This is true for the National Children's Study (NCS), a large-scale longitudinal study that will enroll women both prior to conception and during pregnancy and collect information on their environment, their pregnancies, and their children's development through early adulthood-with a goal of assessing key exposure/outcome relationships among a cohort of approximately 100 000 children. The success of the NCS will significantly depend on the accurate, yet cost-effective, characterization of environmental exposures thought to be related to the health outcomes of interest. The purpose of this paper is to explore the use of cost saving, yet valid and adequately powered statistical approaches for gathering exposure information within epidemiological cohort studies. The proposed approach involves the collection of detailed exposure assessment information on a specially selected subset of the study population, and collection of less-costly, and presumably less-detailed and less-burdensome, surrogate measures across the entire cohort. We show that large-scale efficiency in costs and burden may be achieved without making substantive sacrifices on the ability to draw reliable inferences concerning the relationship between exposure and health outcome. Several detailed scenarios are provided that document how the targeted sub-sampling design strategy can benefit large cohort studies like the NCS, as well as other more focused environmental epidemiologic studies.

Salivary Gland Thrombostasin Isoforms Differentially Regulate Blood Uptake of Horn Flies Fed on Control- and Thrombostasin-vaccinated Cattle

Journal of Medical Entomology. Jul, 2010  |  Pubmed ID: 20695276

Thrombostasin (TS) is an anticlotting protein found in saliva of Haematobia irritans (horn flies). The polymorphic nature of the ts gene was first associated with success of horn flies blood feeding on a laboratory host, New Zealand White rabbits. In this study, we report results of similar studies testing blood uptake of horn flies feeding on a natural host, cattle. These studies confirmed the association of ts genotype with blood uptake of horn flies and showed that it was host species specific. In contrast to rabbits, blood uptake volumes of homozygous ts10 horn flies were lower than those of other ts genotypes when fed on control (ovalbumin-vaccinated) cattle. Cattle vaccinated with recombinant protein isoforms, rTS9 or rTB8, resisted horn fly feeding by yielding lower blood volumes compared with flies feeding on control cattle. The specific impact of vaccination, however, varied by ts genotype of flies. Cattle vaccinated with isoform rTS9 resisted flies of ts2, ts9, and tb8 genotype. Vaccination with isoform rTB8 produced resistance to ts8, ts9, and tb8 genotype flies. Horn flies of genotype ts10 were not affected by vaccination with either TS isoform and fed as well on rTS9- and rTB8-vaccinated as on control-vaccinated cattle. These experimental results confirm the efficacy of vaccines targeting horn fly salivary proteins and provide new insight into the dynamics of horn fly-cattle interactions in nature.

Psychological Health in Patients with ALS is Maintained As Physical Function Declines

Amyotrophic Lateral Sclerosis : Official Publication of the World Federation of Neurology Research Group on Motor Neuron Diseases. Jul, 2011  |  Pubmed ID: 21294667

Although quality of life (QoL) in patients with ALS has been shown to be independent of physical function and to be maintained over time, the status of psychological health over the disease course has not been studied using an ALS-specific instrument. It is also uncertain how three common interventions - antidepressants, percutaneous endoscopic gastrostomy (PEG), and non-invasive ventilatory support (NIPPV) - influence psychological health. We performed a retrospective review of the Negative Emotion subscale (NES) score, a measure of psychological health within the ALS-Specific QoL Instrument. Analysis of 72 patients over three months, and of a subset of 48 over six months, showed stability of psychological health despite a decline in the ALS Functional Rating Scale-Revised to 88.4% of baseline at three months and 82.6% at six months. NES did not change after antidepressants, PEG, or NIPPV, although there was a suggestion of improvement with antidepressants in a subgroup. In conclusion, as with overall QoL, psychological health of ALS patients as measured with an ALS-specific instrument does not decline as physical function is lost. Supports found in a multidisciplinary ALS clinic may influence expectations, facilitate response shift, and stabilize psychological health while masking the independent effects of specific interventions.

Atopy History and the Genomics of Wheezing After Influenza Vaccination in Children 6-59 Months of Age

Vaccine. Apr, 2011  |  Pubmed ID: 21396408

A multinational clinical trial compared the safety and efficacy of intranasal trivalent live attenuated influenza vaccine (LAIV) with intramuscular trivalent inactivated vaccine (TIV) in very young children prior to the 2004-5 influenza season [1]. Wheezing was noted more often in recipients of LAIV and laboratory-confirmed influenza infection was noted more often in recipients of TIV. We sought to determine whether epidemiologic or genetic factors were associated with these outcomes.

Heifer Development Systems: a Comparison of Grazing Winter Range or Corn Residue

Journal of Animal Science. Aug, 2011  |  Pubmed ID: 21478447

Two experiments at 2 Nebraska locations evaluated effects of heifer development system on growth and pregnancy rate. In Exp. 1, heifers (n=270, BW=225 ± 2 kg) grazed winter Sandhills range (WR) or west central Nebraska corn residue (CR) with a supplement (0.45 kg/animal; 31% CP; 80 mg·animal(-1)·d(-1) of monensin). In Exp. 2, heifers (n=180, BW = 262 ± 3 kg) grazed eastern Nebraska WR or CR with a supplement (0.45 to 0.90 kg/d; 31% CP; 80 to 160 mg·animal(-1)·d(-1) of monensin). The CR heifers tended to have less (P=0.10) ADG compared with WR heifers before breeding in Exp. 1; however, prebreeding ADG was similar (P=0.77) in Exp. 2. Prebreeding BW, percentage of mature BW at breeding, and pregnancy determination BW were similar (P ≥ 0.14) for CR and WR in both experiments. Percentage of heifers pubertal at breeding, AI conception, and AI pregnancy rate (Exp. 2) and final pregnancy rate in both experiments were also similar (P ≥ 0.27) for CR and WR heifers. Precalving BW, percentage of calves born in the first 21 d, calf birth date, calf birth BW, and dystocia score were all similar (P ≥ 0.21) for CR and WR heifers in both experiments. Cow BW at weaning, calf weaning BW, adjusted 205-d calf BW, and second season pregnancy rates were not affected (P ≥ 0.16) by treatment. Heifer development system did not affect (P ≥ 0.56) the cost of producing 1 pregnant heifer in Exp. 1 or 2. Development on CR may reduce ADG before breeding, but did not affect pregnancy rate. Heifer development using CR or WR postweaning resulted in similar reproductive performance and development cost.

Pannexin-1 is Required for ATP Release During Apoptosis but Not for Inflammasome Activation

Journal of Immunology (Baltimore, Md. : 1950). Jun, 2011  |  Pubmed ID: 21508259

Apoptotic cell death is important for embryonic development, immune cell homeostasis, and pathogen elimination. Innate immune cells also undergo a very rapid form of cell death termed pyroptosis after activating the protease caspase-1. The hemichannel pannexin-1 has been implicated in both processes. In this study, we describe the characterization of pannexin-1-deficient mice. LPS-primed bone marrow-derived macrophages lacking pannexin-1 activated caspase-1 and secreted its substrates IL-1β and IL-18 normally after stimulation with ATP, nigericin, alum, silica, flagellin, or cytoplasmic DNA, indicating that pannexin-1 is dispensable for assembly of caspase-1-activating inflammasome complexes. Instead, thymocytes lacking pannexin-1, but not the P2X7R purinergic receptor, were defective in their uptake of the nucleic acid dye YO-PRO-1 during early apoptosis. Cell death was not delayed but, unlike their wild-type counterparts, Panx1(-/-) thymocytes failed to recruit wild-type peritoneal macrophages in a Transwell migration assay. These data are consistent with pannexin-1 liberating ATP and other yet to be defined "find me" signals necessary for macrophage recruitment to apoptotic cells.

Complex Retrieval of Embedded IVC Filters: Alternative Techniques and Histologic Tissue Analysis

Cardiovascular and Interventional Radiology. May, 2011  |  Pubmed ID: 21562933

PURPOSE: We evaluated the safety and effectiveness of alternative endovascular methods to retrieve embedded optional and permanent filters in order to manage or reduce risk of long-term complications from implantation. Histologic tissue analysis was performed to elucidate the pathologic effects of chronic filter implantation. METHODS: We studied the safety and effectiveness of alternative endovascular methods for removing embedded inferior vena cava (IVC) filters in 10 consecutive patients over 12 months. Indications for retrieval were symptomatic chronic IVC occlusion, caval and aortic perforation, and/or acute PE (pulmonary embolism) from filter-related thrombus. Retrieval was also performed to reduce risk of complications from long-term filter implantation and to eliminate the need for lifelong anticoagulation. All retrieved specimens were sent for histologic analysis. RESULTS: Retrieval was successful in all 10 patients. Filter types and implantation times were as follows: one Venatech (1,495 days), one Simon-Nitinol (1,485 days), one Optease (300 days), one G2 (416 days), five Günther-Tulip (GTF; mean 606 days, range 154-1,010 days), and one Celect (124 days). There were no procedural complications or adverse events at a mean follow-up of 304 days after removal (range 196-529 days). Histology revealed scant native intima surrounded by a predominance of neointimal hyperplasia and dense fibrosis in all specimens. Histologic evidence of photothermal tissue ablation was confirmed in three laser-treated specimens. CONCLUSION: Complex retrieval methods can now be used in select patients to safely remove embedded optional and permanent IVC filters previously considered irretrievable. Neointimal hyperplasia and dense fibrosis are the major components that must be separated to achieve successful retrieval of chronic filter implants.

Near-infrared-labeled Tetracycline Derivative is an Effective Marker of Bone Deposition in Mice

Analytical Biochemistry. Sep, 2011  |  Pubmed ID: 21645491

Bone-specific compounds have been used effectively for the detection of bone mineralization, growth, and morphological changes. These agents typically contain iminodiacetic acid groups that can form complexes with apatite and fluoresce in the visible spectrum. We exploited a subset of these chemical chelators to produce a near-infrared (NIR) optical bone marker for preclinical animal imaging. By conjugating target compounds to IRDye 800CW, we extended the effective fluorescence signal detection to the NIR region without affecting the compound's ability to function as a marker of the mineralization process. Calcein and a tetracycline derivative (BoneTag agent [BT]) bound specifically to differentiated mineralized osteoblast cultures, with the latter exhibiting 6-fold higher signal intensities. Subsequent in vivo testing demonstrated effective skeletal labeling with IRDye 800CW BT. We were able to identify a changing mineralization front in bone sections from (i) normal growing mice injected with IRDye 800CW BT 6weeks prior to the administration of IRDye 680 BT and (ii) an osteoporosis mouse model comparing cortical bone in sham-treated and ovariectomized mice. These results provide evidence that the NIR-labeled BT is effective as a general marker of skeletal features and an indicator of the bone mineralization and remodeling processes.

Elimination of Human Onchocerciasis: History of Progress and Current Feasibility Using Ivermectin (Mectizan(®)) Monotherapy

Acta Tropica. Sep, 2011  |  Pubmed ID: 20801094

We review and analyze approaches over a 65 year period that have proven successful for onchocerciasis control in several different epidemiological settings. These include vector control with the goal of transmission interruption versus the use of mass drug administration using ivermectin (Mectizan(®)) monotherapy. Ivermectin has proven exceedingly effective because it is highly efficacious against Onchocerca volvulus microfilariae, the etiological agent of onchocercal skin and ocular disease and the infective stage for the vector. For these reasons, the drug was donated by the Merck Company for regional control programs in Africa and the Americas. Recurrent treatment with ivermectin at semi-annual intervals also impacts adult worms and result in loss of fecundity and increased mortality. Using a strategy of 6-monthly treatments with high coverage rates, the Onchocerciasis Elimination Program for the Americas has interrupted transmission in seven of the thirteen foci in the Americas and is on track to eliminate onchocerciasis in the region by 2015. Treatments given annually or semi-annually for 15-17 years in three hyperendemic onchocerciasis foci in Mali and Senegal also have resulted in a few infections in the human population with transmission levels below thresholds postulated for elimination. Follow-up evaluations did not detect any recrudescence of infection or transmission, suggesting that onchocerciasis elimination could be feasible with Mectizan(®) treatment in some endemic foci in Africa.

Microbiological Efficacy of a New Ophthalmic Formulation of Moxifloxacin Dosed Twice-daily for Bacterial Conjunctivitis

Advances in Therapy. Jul, 2011  |  Pubmed ID: 21681652

An alternative formulation of 0.5% moxifloxacin ophthalmic solution (Moxeza, MOXI-AF, Alcon Laboratories, Inc., Fort Worth, TX, USA) containing xanthan gum to prolong retention on the eye has been developed. MOXI-AF was designed to optimize the treatment regimen for bacterial conjunctivitis for the convenience of the patient with twice-daily dosing.

Neighborhood Perceptions and Parent Outcomes in Family Based Prevention Programs for Thai Adolescents: the Role of Program Engagement

Journal of Drug Education. 2011  |  Pubmed ID: 21887999

Due to concerns over Thai adolescent risky behaviors, effective prevention strategies are needed. Determining the role neighborhood context plays in program engagement and outcomes may inform these strategies. This study includes 170 mother-adolescent pairs (M = 13.44, SD = .52) in Bangkok, Thailand in a prevention program for adolescent substance use and sexual risk. Neighborhoods were related to engagement, which was critical to outcomes. Neighborhood disorganization was related to confidence in program effects and program completion. Completion was related to increased ATOD communication. Neighborhood cohesion was related to less program enjoyment, while neighborhood social control was related to more enjoyment. Enjoyment was related to increased ATOD communication and formation and monitoring of alcohol rules. Prevention strategies should focus on neighborhood contexts and enhancing engagement.

Correlation of a Feline Muscle Mass Score with Body Composition Determined by Dual-energy X-ray Absorptiometry

The British Journal of Nutrition. Oct, 2011  |  Pubmed ID: 22005437

Body condition scoring (BCS) systems primarily assess body fat. Both overweight and underweight animals may have loss of lean tissue that may not be noted using standard BCS systems. Catabolism of lean tissue can occur rapidly, may account for a disproportionate amount of body mass loss in sick cats and can have deleterious consequences for outcome. Therefore, along with evaluation of body fat, patients should undergo evaluation of muscle mass. The aims of the present study were first to evaluate the repeatability and reproducibility of a 4-point feline muscle mass scoring (MMS) system and second to assess the convergent validity of MMS by dual-energy X-ray absorptiometry (DXA). MMS was as follows: 3, normal muscle mass; 2, slight wasting; 1, moderate wasting; 0, severe wasting. For the first aim, forty-four cats were selected for evaluation based on age and BCS, and for the second aim, thirty-three cats were selected based on age, BCS and MMS. Cats were scored by ten different evaluators on three separate occasions. Body composition was determined by DXA. Inter- and intra-rater agreement were assessed using kappa analysis. Correlation between MMS and BCS, age, percentage lean body mass and lean body mass (LBM) was determined using Spearman's rank-order correlation. The MMS showed moderate inter-rater agreement in cats that scored normal or severely wasted (κ = 0.48-0.53). Intra-rater agreement was substantial (κ = 0.71-0.73). The MMS was significantly correlated with BCS (r 0.76, P < 0.0001), age (r - 0.75, P < 0.0001), LBM (g) (r 0.62, P < 0.0001) and percentage LBM (r - 0.49, P < 0.0035). Additional investigation is needed to determine whether the MMS can be refined and to assess its clinical applicability.

Planning for the Next Influenza Pandemic: Using the Science and Art of Logistics

American Journal of Disaster Medicine. Jul-Aug, 2011  |  Pubmed ID: 22010601

The complexities and challenges for healthcare providers and their efforts to provide fundamental basic items to meet the logistical demands of an influenza pandemic are discussed in this article. The supply chain, planning, and alternatives for inevitable shortages are some of the considerations associated with this emergency mass critical care situation. The planning process and support for such events are discussed in detail with several recommendations obtained from the literature and the experience from recent mass casualty incidents (MCIs). The first step in this planning process is the development of specific triage requirements during an influenza pandemic. The second step is identification of logistical resources required during such a pandemic, which are then analyzed within the proposed logistics science and art model for planning purposes. Resources highlighted within the model include allocation and use of work force, bed space, intensive care unit assets, ventilators, personal protective equipment, and oxygen. The third step is using the model to discuss in detail possible workarounds, suitable substitutes, and resource allocation. An examination is also made of the ethics surrounding palliative care within the construction of an MCI and the factors that will inevitably determine rationing and prioritizing of these critical assets to palliative care patients.

Successful Implementation of Thai Family Matters: Strategies and Implications

Health Promotion Practice. Nov, 2011  |  Pubmed ID: 22090152

This article discusses the successful process used to assess the feasibility of implementing the Family Matters program in Bangkok, Thailand. This is important work since adopting and adapting evidence-based programs is a strategy currently endorsed by leading prevention funding sources, particularly in the United States. The original Family Matters consists of four booklets designed to increase parental communication with their adolescent children in order to delay onset of or decrease alcohol, tobacco, and other drug use. As part of the program, health educators contact parents by telephone to support them in the adoption of the program. Each booklet addresses a key aspect of strengthening families and protecting young people from unhealthy behaviors related to alcohol and other drug use. Adaptation of the program for Bangkok focused on cultural relevance and the addition of a unit targeting adolescent dating and sexual behavior. A total of 170 families entered the program, with the majority (85.3%) completing all five booklets. On average, the program took 16 weeks to complete, with families reporting high satisfaction with the program. This article provides greater detail about the implementation process and what was learned from this feasibility trial.

Pharmacists' Perceptions of Participation in a Community Pharmacy-Based Nicotine Replacement Therapy Distribution Program

Journal of Community Health. Dec, 2011  |  Pubmed ID: 22143162

The community pharmacy has been proposed as an ideal location for providing smoking cessation therapy to large numbers of patients. Studies of public health initiatives providing free nicotine replacement products through telephone quitlines have found increased call volumes and cessation rates. The purpose of this study was to evaluate a program where nicotine replacement therapy starter packs were provided to patients through community pharmacies at no cost. An online survey was developed to assess community pharmacists' participation in the program, perceptions of the initiative as a whole, and perceptions of smoking cessation counseling activities. Eighty-three pharmacists working at participating pharmacies completed the survey (65% response rate). Ninety-nine percent of pharmacists provided smoking cessation counseling during the study period; the median (IQR) number of patients counseled over the initial 3.5-months of the NRT distribution program was 50 (24-100), and the median number of minutes per counseling session was five (3-7). Most (89%) agreed smoking cessation counseling was accommodated into the pharmacy work-flow. A majority (85%) agreed the community pharmacy is an ideal location for distributing free NRT products and that the program should be replicated in other pharmacies (78%). Participating pharmacists viewed the program positively and perceived it to be effective in helping patients quit smoking. In conclusion, the community pharmacy is a viable location for implementation of community-based public health initiatives related to smoking cessation.

Parent-Teen Communication About Sex in Urban Thai Families

Journal of Health Communication. Dec, 2011  |  Pubmed ID: 22206411

This study describes sexual communication among Thai parents and their teens and identifies variables related to communication about sex in urban Thai families. Data were derived from 420 families whose teenage children ages 13-14 years were randomly selected using the probability proportional to size technique. Interviews were conducted with 1 parent and 1 teenage child in each family. In-depth interviews were also conducted in 30 parents and teens drawn from the same 420 families. Results showed that parents were most likely to talk with their teens about body changes and dating; however, less discussion about sex-related issues, birth control, and HIV/AIDS occurred. More daughters than sons reported frequent discussions with their parents about sex. Parents who believed their teens had been involved in sexual activity were more likely to talk about HIV/AIDS and the difficulty of teenagers having babies, instead of talking about sexual intercourse or when to start having sex. Multiple regression analysis indicated that gender of the child (female), parental religiosity, and parental perception of teen sexual activity were significant predictors of increased sexual communication in Thai families. The findings suggest a need for approaches designed to facilitate communication skills about sex-related issues among Thai parents.

The Balance of Proangiogenic and Antiangiogenic VEGFA Isoforms Regulate Follicle Development

Cell and Tissue Research. Feb, 2012  |  Pubmed ID: 22322423

Vascular endothelial growth factor A (VEGFA) has been extensively studied because of its role in follicular development and is a principal angiogenic factor essential for angiogenesis. Since vascularization of the theca layer increases as follicles progress in size through preantral and antral stages, VEGFA might influence follicle growth via the regulation of angiogenesis. However, VEGFA might also influence follicular development through nonangiogenic mechanisms, since its expression has been localized in nonvascular follicles and cells. Alternative mRNA splicing of eight exons from the VEGFA gene results in the formation of various VEGFA isoforms. Each isoform has unique properties and is identified by the number of amino acids within the mature protein. Proangiogenic isoforms (VEGFA_XXX) are encoded by exon 8a, whereas a sister set of isoforms (VEGFA_XXXB) with antiangiogenic properties is encoded by exon 8b. The antiangiogenic VEGFA_XXXB isoforms comprise the majority of VEGFA expressed in most tissues, whereas expression of the proangiogenic VEGFA isoforms is upregulated in tissues undergoing active angiogenesis. Although proangiogenic and antiangiogenic isoforms can now be distinguished from one another, many studies evaluating VEGFA in ovarian and follicular development up to now have not differentiated proangiogenic VEGFA from antiangiogenic VEGFA. Experiments from our laboratory indicate that proangiogenic VEGFA promotes follicle recruitment and early follicular development and antiangiogenic VEGFA inhibits these processes. The balance of proangiogenic versus antiangiognic VEGFA isoforms is thus of importance during follicle development. Further studies are warranted to elucidate the way that this balance regulates follicular formation and progression.

Winter Severity Predicts the Timing of Host Shifts in the Mosquito Culex Erraticus

Biology Letters. Mar, 2012  |  Pubmed ID: 22399787

In temperate regions, seasonal epidemics of many mosquito-borne viruses are triggered when mosquito populations shift from feeding on avian to mammalian hosts. We investigated effects of temperature on the timing of bird-to-mammal shifts using an 8 year dataset of blood-meals from a mosquito (Culex erraticus) in Alabama, USA. As expected, Cx. erraticus shifted from avian to mammalian hosts each year. The timing of the shift, however, varied considerably among years. Harshness of the preceding winter (chill accumulation) explained 93 per cent of the variation in the timing of bird-to-mammal shifts, with shifts occurring later in years following harsher winters. We hypothesize that winter temperatures drive the timing of bird-to-mammal shifts through effects on host reproductive phenology. Because mosquitoes target birds during the nesting season, and bird nesting occurs later in years following colder winters, later nesting dates result in a concomitant delay in the timing of bird-to-mammal host shifts. Global increases in winter temperatures could cause significant changes in the timing of seasonal host shifts by mosquitoes, with prolonged periods of epidemic transmission of mosquito-borne diseases.

VEGFA Family Isoforms Regulate Spermatogonial Stem Cell Homeostasis in Vivo

Endocrinology. Feb, 2012  |  Pubmed ID: 22147017

The objective of the present study was to investigate vascular endothelial growth factor A (VEGFA) isoform regulation of cell fate decisions of spermatogonial stem cells (SSC) in vivo. The expression pattern and cell-specific distribution of VEGF isoforms, receptors, and coreceptors during testis development postnatal d 1-180 suggest a nonvascular function for VEGF regulation of early germ cell homeostasis. Populations of undifferentiated spermatogonia present shortly after birth were positive for VEGF receptor activation as demonstrated by immunohistochemical analysis. Thus, we hypothesized that proangiogenic isoforms of VEGF (VEGFA(164)) stimulate SSC self-renewal, whereas antiangiogenic isoforms of VEGF (VEGFA(165)b) induce differentiation of SSC. To test this hypothesis, we used transplantation to assay the stem cell activity of SSC obtained from neonatal mice treated daily from postnatal d 3-5 with 1) vehicle, 2) VEGFA(164), 3) VEGFA(165)b, 4) IgG control, 5) anti-VEGFA(164), and 6) anti-VEGFA(165)b. SSC transplantation analysis demonstrated that VEGFA(164) supports self-renewal, whereas VEGFA(165)b stimulates differentiation of mouse SSC in vivo. Gene expression analysis of SSC-associated factors and morphometric analysis of germ cell populations confirmed the effects of treatment on modulating the biological activity of SSC. These findings indicate a nonvascular role for VEGF in testis development and suggest that a delicate balance between VEGFA(164) and VEGFA(165)b isoforms orchestrates the cell fate decisions of SSC. Future in vivo and in vitro experimentation will focus on elucidating the mechanisms by which VEGFA isoforms regulate SSC homeostasis.

Topical Ophthalmic Moxifloxacin Elicits Minimal or No Selection of Fluoroquinolone Resistance Among Bacteria Isolated from the Skin, Nose, and Throat

Journal of Pediatric Ophthalmology and Strabismus. Mar, 2012  |  Pubmed ID: 22074357

To investigate whether moxifloxacin therapy of bacterial conjunctivitis in children changes the moxifloxacin susceptibility of bacterial isolates in eyes, cheeks below eyes, nares, and throat.

Effects of Resistance Training on Adiposity and Metabolism After Spinal Cord Injury

Medicine and Science in Sports and Exercise. Jan, 2012  |  Pubmed ID: 21659900

This pilot work was conducted to evaluate the effects of neuromuscular electrical stimulation resistance training (RT) of the paralyzed knee extensor muscle groups on skeletal muscle and intramuscular fat (IMF) cross-sectional areas, trunk visceral adipose tissue (VAT), carbohydrate, and lipid profiles in men with spinal cord injury.