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Find video protocols related to scientific articles indexed in Pubmed.
Neurotoxicity following acute inhalation of aerosols generated during resistance spot weld-bonding of carbon steel.
Inhal Toxicol
PUBLISHED: 09-30-2014
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Abstract Welding generates complex metal aerosols, inhalation of which is linked to adverse health effects among welders. An important health concern of welding fume (WF) exposure is neurological dysfunction akin to Parkinson's disease (PD). Some applications in manufacturing industry employ a variant welding technology known as "weld-bonding" that utilizes resistance spot welding, in combination with adhesives, for metal-to-metal welding. The presence of adhesives raises additional concerns about worker exposure to potentially toxic components like Methyl Methacrylate, Bisphenol A and volatile organic compounds (VOCs). Here, we investigated the potential neurotoxicological effects of exposure to welding aerosols generated during weld-bonding. Male Sprague-Dawley rats were exposed (25?mg/m(3) targeted concentration; 4?h/day?×?13 days) by whole-body inhalation to filtered air or aerosols generated by either weld-bonding with sparking (high metal, low VOCs; HM) or without sparking (low metal; high VOCs; LM). Fumes generated under these conditions exhibited complex aerosols that contained both metal oxide particulates and VOCs. LM aerosols contained a greater fraction of VOCs than HM, which comprised largely metal particulates of ultrafine morphology. Short-term exposure to LM aerosols caused distinct changes in the levels of the neurotransmitters, dopamine (DA) and serotonin (5-HT), in various brain areas examined. LM aerosols also specifically decreased the mRNA expression of the olfactory marker protein (Omp) and tyrosine hydroxylase (Th) in the olfactory bulb. Consistent with the decrease in Th, LM also reduced the expression of dopamine transporter (Slc6a3; Dat), as well as, dopamine D2 receptor (Drd2) in the olfactory bulb. In contrast, HM aerosols induced the expression of Th and dopamine D5 receptor (Drd5) mRNAs, elicited neuroinflammation and blood-brain barrier-related changes in the olfactory bulb, but did not alter the expression of Omp. Our findings divulge the differential effects of LM and HM aerosols in the brain and suggest that exposure to weld-bonding aerosols can potentially elicit neurotoxicity following a short-term exposure. However, further investigations are warranted to determine if the aerosols generated by weld-bonding can contribute to persistent long-term neurological deficits and/or neurodegeneration.
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Development and characterization of a resistance spot welding aerosol generator and inhalation exposure system.
Inhal Toxicol
PUBLISHED: 08-20-2014
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Limited information exists regarding the health risks associated with inhaling aerosols that are generated during resistance spot welding of metals treated with adhesives. Toxicology studies evaluating spot welding aerosols are non-existent. A resistance spot welding aerosol generator and inhalation exposure system was developed. The system was designed by directing strips of sheet metal that were treated with an adhesive to two electrodes of a spot welder. Spot welds were made at a specified distance from each other by a computer-controlled welding gun in a fume collection chamber. Different target aerosol concentrations were maintained within the exposure chamber during a 4-h exposure period. In addition, the exposure system was run in two modes, spark and no spark, which resulted in different chemical profiles and particle size distributions. Complex aerosols were produced that contained both metal particulates and volatile organic compounds (VOCs). Size distribution of the particles was multi-modal. The majority of particles were chain-like agglomerates of ultrafine primary particles. The submicron mode of agglomerated particles accounted for the largest portion of particles in terms of particle number. Metal expulsion during spot welding caused the formation of larger, more spherical particles (spatter). These spatter particles appeared in the micron size mode and accounted for the greatest amount of particles in terms of mass. With this system, it is possible to examine potential mechanisms by which spot welding aerosols can affect health, as well as assess which component of the aerosol may be responsible for adverse health outcomes.
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Improvement in facial erythema within 30 minutes of initial application of brimonidine tartrate in patients with rosacea.
J Drugs Dermatol
PUBLISHED: 06-12-2014
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Brimonidine tartrate (BT) 0.5% gel demonstrated significantly greater efficacy versus vehicle gel once-daily for the treatment of moderate to severe erythema of rosacea.
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Effect of fermentation media on the production, efficacy, and storage stability of Metarhizium brunneum microsclerotia formulated as a prototype granule.
J. Econ. Entomol.
PUBLISHED: 04-30-2014
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New liquid fermentation techniques for the production of the bioinsecticidal fungus Metarhizium brunneum strain F-52 have resulted in the formation of microsclerotia (MS), a compact, melonized-hyphal structure capable of surviving desiccation and formulation as dry granules. When rehydrated, these MS granules germinate to produce conidia that can infect susceptible insects. Fermentation media containing cottonseed or soy flours as nitrogen sources and formulated at two carbon to nitrogen ratios (C:N), 30:1 or 50:1, were evaluated forproduction of microsclerotia. Dry MS granule samples were compared for storage stability based on conidia production, and insecticidal activity against larvae of the lesser mealworm, Alphitobius diaperinus (Panzer), using a potting soil bioassay. Cottonseed and soy flours were equivalent for production, MS granule viability, and insecticidal activity. Fermentation media containing higher nitrogen concentrations (30:1 C:N) resulted in greater biomass accumulation and greater production of conidia from granules regardless of the nitrogen source. MS granules made with M. brunneum cultures grown in media with 30:1 C:N produced 8.5 x 10(9) conidia per gram of granules after 8-d incubation, significantly higher than MS granules made using fungus produced using 50:1 C:N media (5.5 x 10(9) conidia per gram dry MS granules). The LC50 for larval mortality was 8.05 x 10(5) conidia per cup, equivalent to applications of 94 or 147 microg granules per cup for granules made from high and low nitrogen media, respectively. Measurements of water activity were not significantly different among granule samples (0.28-0.29) even though granules made from high nitrogen media had higher moisture content (> 5.2%) compared with granules made from low nitrogen media (< 4.6%). Higher initial conidial production was reflected in longer storage stability at 25 degrees C, with half-lives estimated at 3.7 and 1.7 wk for 30:1 and 50:1 C:N ratios, respectively. These results support further evaluation of MS granule formulations for the control of soil-inhabiting insect pests.
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Conserved oncogenic behavior of the FAM83 family regulates MAPK signaling in human cancer.
Mol. Cancer Res.
PUBLISHED: 04-15-2014
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FAM83B (family with sequence similarity 83, member B) was recently identified as a novel oncogene involved in activating CRAF/MAPK signaling and driving epithelial cell transformation. FAM83B is one of eight members of a protein family (FAM83) characterized by a highly conserved domain of unknown function (DUF1669), which is necessary and sufficient to drive transformation. Here, it is demonstrated that additional FAM83 members also exhibit oncogenic properties and have significantly elevated levels of expression in multiple human tumor types using a TissueScan Cancer Survey Panel PCR array and database mining. Furthermore, modeling the observed tumor expression of FAM83A, FAM83C, FAM83D, or FAM83E promoted human mammary epithelial cell (HMEC) transformation, which correlated with the ability of each FAM83 member to bind CRAF (RAF1) and promote CRAF membrane localization. Conversely, ablation of FAM83A or FAM83D from breast cancer cells resulted in diminished MAPK signaling with marked suppression of growth in vitro and tumorigenicity in vivo. Importantly, each FAM83 member was determined to be elevated in at least one of 17 distinct tumor types examined, with FAM83A, FAM83B, and FAM83D most frequently overexpressed in several diverse tissue types. Finally, evidence suggests that elevated expression of FAM83 members is associated with elevated tumor grade and decreased overall survival.
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HiJAK'd Signaling; the STAT3 Paradox in Senescence and Cancer Progression.
Cancers (Basel)
PUBLISHED: 02-08-2014
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Clinical and epidemiological data have associated chronic inflammation with cancer progression. Most tumors show evidence of infiltrating immune and inflammatory cells, and chronic inflammatory disorders are known to increase the overall risk of cancer development. While immune cells are often observed in early hyperplastic lesions in vivo, there remains debate over whether these immune cells and the cytokines they produce in the developing hyperplastic microenvironment act to inhibit or facilitate tumor development. The interleukin-6 (IL-6) family of cytokines, which includes IL-6 and oncostatin M (OSM), among others (LIF, CT-1, CNTF, and CLC), are secreted by immune cells, stromal cells, and epithelial cells, and regulate diverse biological processes. Each of the IL-6 family cytokines signals through a distinct receptor complex, yet each receptor complex uses a shared gp130 subunit, which is critical for signal transduction following cytokine binding. Activation of gp130 results in the activation of Signal Transducer and Activator of Transcription 3 (STAT3), and the Mitogen-Activated Protein Kinase (MAPK) and Phosphatidylinositol 3-Kinase (PI3K) signaling cascades. Tumor suppressive signaling can often be observed in normal cells following prolonged STAT3 activation. However, there is mounting evidence that the IL-6 family cytokines can contribute to later stages of tumor progression in many ways. Here we will review how the microenvironmental IL-6 family cytokine OSM influences each stage of the transformation process. We discuss the intrinsic adaptations a developing cancer cell must make in order to tolerate and circumvent OSM-mediated growth suppression, as well as the OSM effectors that are hijacked during tumor expansion and metastasis. We propose that combining current therapies with new ones that suppress the signals generated from the tumor microenvironment will significantly impact an oncologist's ability to treat cancer.
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Comparing the neuropsychiatric inventory and the revised memory and behavior problems checklist for associations with caregiver burden and depressive symptoms.
Int Psychogeriatr
PUBLISHED: 01-15-2014
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Few empirical studies compare the ability of prominent measures of behavioral and psychological symptoms of dementia (BPSD) to explain key caregiver outcomes. We compared the respective abilities of the Neuropsychiatric Inventory (NPI) and the Revised Memory and Behavior Problems Checklist (RMBPC) to detect associations between BPSD and caregiver depressive symptoms. Our results may facilitate measurement decisions for researchers and clinicians.
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Design rules for efficient transgene expression in plants.
Plant Biotechnol. J.
PUBLISHED: 01-08-2014
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Sustained expression of transgenes in specified developmental patterns is commonly needed in plant biotechnology, but obstructed by transgene silencing. Here, we present a set of gene design rules, tested on the silencing-susceptible beetle luc and bacterial ims genes, expressed in sugarcane. Designs tested independently or in combination included removal of rare codons, removal of RNA instability sequences, blocking of likely endogenous sRNA binding sites and randomization of non-rare codons. Stable transgene expression analyses, on multiple independent lines per construct, showed greatest improvement from the removal of RNA instability sequences, accompanied by greatly reduced transcript degradation evident in northern blot analysis. We provide a set of motifs that readily can be eliminated concurrently with rare codons and undesired structural features such as repeat sequences, using Gene Designer 2.0 software. These design rules yielded 935- and 5-fold increased expression in transgenic callus, relative to the native luc and ims sequences; and gave sustained expression under the control of sugarcane and heterologous promoters over several years in greenhouse and field trials. The rules can be applied easily with codon usage tables from any plant species, providing a simple and effective means to achieve sustained expression of otherwise silencing-prone transgenes in plants.
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ETV1 positively regulates transcription of tumor suppressor ARF.
Cancer Biol. Ther.
PUBLISHED: 10-23-2013
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ETV1 (ETS variant 1) is a transcription factor from the ETS family and an oncogene in several types of human malignancies. Paradoxically, a predicted inactivating mutation in ETV1 was previously found in a clone of HT1080 cells with reduced activity of p53. We report that elevated expression of ETV1 makes p53-null tumor cells hypersensitive to restoration of said tumor suppressor. Furthermore, elevated levels of either wild-type ETV1 or its truncated derivative, dETV1, which mimics the product of an oncogenic rearrangement in certain tumors, results in increased expression of mRNA for p14ARF, a known activator of p53. Accordingly, expression of a luciferase reporter, which is driven by a putative ARF promoter, was elevated by concomitant expression of either ETV1 or dETV1. Our observations point to yet another example of a tumor suppressor gene being activated by a potentially oncogenic signal. A better understanding of the mechanisms that allow a cell to bypass such safeguards is needed in order to predict and prevent the development of an oncogene-tolerant state during cancer evolution.
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Coordinated regulation of p31(Comet) and Mad2 expression is required for cellular proliferation.
Cell Cycle
PUBLISHED: 10-15-2013
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p31(Comet) is a well-known interacting partner of the spindle assembly checkpoint (SAC) effector molecule Mad2. At the molecular level it is well established that p31(Comet) promotes efficient mitotic exit, specifically the metaphase-anaphase transition, by antagonizing Mad2 function. However, there is little knowledge of how p31(Comet) is regulated or the physiological importance of controlling p31(Comet). Here, we show that the Rb-E2F pathway regulates p31(Comet) expression. In multiple tumor types (including breast and lung) p31(Comet) expression is increased along with Mad2. Expression of this antagonist-target pair is coordinated in cells and correlated in cancer. Moreover, a narrow range of p31(Comet):Mad2 ratios is compatible with cellular viability. Our data suggest that coordinate regulation is important for the outgrowth of oncogenic cell populations. Our findings suggest that altered p31(Comet):Mad2 expression ratios may provide new insight into altered SAC function and the generation of chromosomal instability in tumors.
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Stabilization of the syndesmosis in the Maisonneuve fracture--a biomechanical study comparing 2-hole locking plate and quadricortical screw fixation.
J Orthop Trauma
PUBLISHED: 09-28-2013
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The aim of this study is to determine whether a 2-hole locking plate has biomechanical advantages over conventional screw stabilization of the syndesmosis in this injury pattern.
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Interobserver and intraobserver reliability assessment of calcaneal fracture classification systems.
J Foot Ankle Surg
PUBLISHED: 08-28-2013
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The aim of the present study was to assess the reliability of commonly used intra-articular calcaneal fracture classification systems and to compare them with the newer AO Integral Classification of Injuries (ICI) system. Forty computed tomography and radiographic images of 40 intra-articular calcaneal fractures were reviewed independently by 3 reviewers on 2 separate occasions and classified according to the Essex-Lopresti, Atkins, Zwipp and Tscherne, Sanders, and AO-ICI classification systems. The reviewers were unaware of the patients identity and all aspects of clinical care. The data were analyzed using kappa (?) statistics to assess the intra- and interobserver reliability. The ? values were calculated for Essex-Lopresti (? = 0.85 intraobserver, ? = 0.78 interobserver), Atkins (? = 0.42 intraobserver, ? = 0.73 interobserver), Zwipp and Tscherne (? = 0.40 intraobserver, ? = 0.47 interobserver), Sanders (? = 0.31 intraobserver, ? = 0.35 interobserver), and AO-ICI (? = 0.41 intraobserver, ? = 0.33 interobserver). The AO-ICI classification system had levels of reproducibility similar to that of the Sanders classification, currently the most widely used system. The Essex-Lopresti classification demonstrated improved reliability compared with that reported in previous studies. This can be attributed to using sagittal computed tomography images, in addition to the originally described plain radiographs, for assessment. This improvement is relevant because of its accepted prognostic predictability.
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Popcorn flavoring effects on reactivity of rat airways in vivo and in vitro.
J. Toxicol. Environ. Health Part A
PUBLISHED: 08-15-2013
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"Popcorn workers lung" is an obstructive pulmonary disease produced by inhalation of volatile artificial butter flavorings. In rats, inhalation of diacetyl, a major component of butter flavoring, and inhalation of a diacetyl substitute, 2,3-pentanedione, produce similar damage to airway epithelium. The effects of diacetyl and 2,3-pentanedione and mixtures of diacetyl, acetic acid, and acetoin, all components of butter flavoring, on pulmonary function and airway reactivity to methacholine (MCh) were investigated. Lung resistance (RL) and dynamic compliance (Cdyn) were negligibly changed 18 h after a 6-h inhalation exposure to diacetyl or 2,3-pentanedione (100-360 ppm). Reactivity to MCh was not markedly changed after diacetyl, but was modestly decreased after 2,3-pentanedione inhalation. Inhaled diacetyl exerted essentially no effect on reactivity to mucosally applied MCh, but 2,3-pentanedione (320 and 360 ppm) increased reactivity to MCh in the isolated, perfused trachea preparation (IPT). In IPT, diacetyl and 2,3-pentanedione (?3 mM) applied to the serosal and mucosal surfaces of intact and epithelium-denuded tracheas initiated transient contractions followed by relaxations. Inhaled acetoin (150 ppm) exerted no effect on pulmonary function and airway reactivity in vivo; acetic acid (27 ppm) produced hyperreactivity to MCh; and exposure to diacetyl + acetoin + acetic acid (250 + 150 + 27 ppm) led to a diacetyl-like reduction in reactivity. Data suggest that the effects of 2,3-pentanedione on airway reactivity are greater than those of diacetyl, and that flavorings are airway smooth muscle relaxants and constrictors, thus indicating a complex mechanism.
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IFN?-dependent increases in STAT1, STAT2, and IRF9 mediate resistance to viruses and DNA damage.
EMBO J.
PUBLISHED: 08-13-2013
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A single high dose of interferon-? (IFN?) activates powerful cellular responses, in which many anti-viral, pro-apoptotic, and anti-proliferative proteins are highly expressed. Since some of these proteins are deleterious, cells downregulate this initial response rapidly. However, the expression of many anti-viral proteins that do no harm is sustained, prolonging a substantial part of the initial anti-viral response for days and also providing resistance to DNA damage. While the transcription factor ISGF3 (IRF9 and tyrosine-phosphorylated STATs 1 and 2) drives the first rapid response phase, the related factor un-phosphorylated ISGF3 (U-ISGF3), formed by IFN?-induced high levels of IRF9 and STATs 1 and 2 without tyrosine phosphorylation, drives the second prolonged response. The U-ISGF3-induced anti-viral genes that show prolonged expression are driven by distinct IFN stimulated response elements (ISREs). Continuous exposure of cells to a low level of IFN?, often seen in cancers, leads to steady-state increased expression of only the U-ISGF3-dependent proteins, with no sustained increase in other IFN?-induced proteins, and to constitutive resistance to DNA damage.
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A coupled sensor-spectrophotometric device for continuous measurement of formaldehyde in indoor environments.
J Expo Sci Environ Epidemiol
PUBLISHED: 07-31-2013
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Despite long-standing awareness of adverse health effects associated with chronic human exposure to formaldehyde, this hazardous air pollutant remains a challenge to measure in indoor environments. Traditional analytical techniques evaluate formaldehyde concentrations over several hours to several days in a single location in a residence, making it difficult to characterize daily temporal and spatial variation in human exposure to formaldehyde. There is a need for portable, easy-to-use devices that are specific and sensitive to gas-phase formaldehyde over short sampling periods so that dynamic processes governing formaldehyde fate, transport, and potential remediation in indoor environments may be studied more effectively. A recently developed device couples a chemical sensor element with spectrophotometric analysis for detection and quantification of part per billion (ppbv) gas-phase formaldehyde concentrations. This study established the ability of the coupled sensor-spectrophotometric device (CSSD) to report formaldehyde concentrations accurately and continuously on a 30-min sampling cycle at low ppbv concentrations previously untested for this device in a laboratory setting. Determination of the method detection limit (MDL), based on 40 samples each at test concentrations of 5 and 10?ppbv, was found to be 1.9 and 2.0?ppbv, respectively. Performance of the CSSD was compared with the dinitrophenylhydrazine (DNPH) derivatization method for formaldehyde concentrations ranging from 5-50?ppbv, and a linear relationship with a coefficient of determination of 0.983 was found between these two analytical techniques. The CSSD was also used to monitor indoor formaldehyde concentrations in two manufactured homes. During this time, formaldehyde concentrations varied from below detection limit to 65?ppbv and were above the US National Institute for Occupational Safety and Health (NIOSH) recommended exposure limit (REL) of 16?ppbv, which is also the exposure limit value now adopted by the US Federal Emergency Management Agency (FEMA) to procure manufactured housing, 80% and 100% of the time, respectively.Journal of Exposure Science and Environmental Epidemiology advance online publication, 2 October 2013; doi:10.1038/jes.2013.61.
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Diacetyl Increases Sensory Innervation and Substance P Production in Rat Trachea.
Toxicol Pathol
PUBLISHED: 07-11-2013
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Inhalation of diacetyl, a butter flavoring, causes airway responses potentially mediated by sensory nerves. This study examines diacetyl-induced changes in sensory nerves of tracheal epithelium. Rats (n = 6/group) inhaled 0-, 25-, 249-, or 346-ppm diacetyl for 6 hr. Tracheas and vagal ganglia were removed 1-day postexposure and labeled for substance P (SP) or protein gene product 9.5 (PGP9.5). Vagal ganglia neurons projecting to airway epithelium were identified by axonal transport of fluorescent microspheres intratracheally instilled 14 days before diacetyl inhalation. End points were SP and PGP9.5 nerve fiber density (NFD) in tracheal epithelium and SP-positive neurons projecting to the trachea. PGP9.5-immunoreactive NFD decreased in foci with denuded epithelium, suggesting loss of airway sensory innervation. However, in the intact epithelium adjacent to denuded foci, SP-immunoreactive NFD increased from 0.01 ± 0.002 in controls to 0.05 ± 0.01 after exposure to 346-ppm diacetyl. In vagal ganglia, SP-positive airway neurons increased from 3.3 ± 3.0% in controls to 25.5 ± 6.6% after inhaling 346-ppm diacetyl. Thus, diacetyl inhalation increases SP levels in sensory nerves of airway epithelium. Because SP release in airways promotes inflammation and activation of sensory nerves mediates reflexes, neural changes may contribute to flavorings-related lung disease pathogenesis.
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Interactions among Bt maize, entomopathogens, and rootworm species (Coleoptera: Chrysomelidae) in the field: effects on survival, yield, and root injury.
J. Econ. Entomol.
PUBLISHED: 06-22-2013
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A 2 yr field study was conducted to determine how a blend of entomopathogens interacted with Bt maize to affect mortality of Diabrotica spp. (Coleoptera: Chrysomelidae), root injury to maize (Zea maize L.) and yield. The blend of entomopathogens included two entomopathogenic nematodes, Steinernema carpocapsae Weiser and Heterorhabditis bacteriophora Poinar, and one entomopathogenic fungus, Metarhizium brunneum (Metschnikoff) Sorokin. Bt maize (event DAS59122-7, which produces Bt toxin Cry34/35Ab1) decreased root injury and survival of western corn rootworm (Diabrotica virgifera virgifera LeConte) and northern corn rootworm (Diabrotica barberi Smith & Lawrence) but did not affect yield. During year 1 of the study, when rootworm abundance was high, entomopathogens in combination with Bt maize led to a significant reduction in root injury. In year 2 of the study, when rootworm abundance was lower, entomopathogens significantly decreased injury to non-Bt maize roots, but had no effect on Bt maize roots. Yield was significantly increased by the addition of entomopathogens to the soil. Entomopathogens did not decrease survival of corn rootworm species. The results suggest that soil-borne entomopathogens can complement Bt maize by protecting roots from feeding injury from corn rootworm when pest abundance is high, and can decrease root injury to non-Bt maize when rootworm abundance is low. In addition, this study also showed that the addition of entomopathogens to soil contributed to an overall increase in yield.
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Tumor microenvironmental signaling elicits epithelial-mesenchymal plasticity through cooperation with transforming genetic events.
Neoplasia
PUBLISHED: 05-30-2013
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Epithelial-to-mesenchymal transition (EMT) facilitates the escape of epithelial cancer cells from the primary tumor site, which is a key event early in metastasis. Here, we explore how extrinsic, tumor microenvironmental cytokines cooperate with intrinsic, genetic changes to promote EMT in human mammary epithelial cells (HMECs). Viral transduction of transforming genetic events into HMECs routinely generated two distinct cell populations. One population retained epithelial characteristics, while an emergent population spontaneously acquired a mesenchymal morphology and properties associated with cancer stem cells (CSCs). Interestingly, the spontaneous mesenchymal/CSCs were unable to differentiate and lacked epithelial-mesenchymal plasticity. In contrast, exposure of the transformed HMECs retaining epithelial characteristics to exogenous transforming growth factor-? (TGF-?) generated a mesenchymal/CSC population with remarkable plasticity. The TGF-?-induced mesenchymal/CSC population was dependent on the continued presence of TGF-?. Removal of TGF-? or pharmacologic or genetic inhibition of TGF-?/SMAD signaling led to the reversion of mesenchymal/CSC to epithelial/non-CSC. Our results demonstrate that targeting exogenous cytokine signaling disrupts epithelial-mesenchymal plasticity and may be an effective strategy to inhibit the emergence of circulating tumor cells. The model of epithelial-mesenchymal plasticity we describe here can be used to identify novel tumor microenvironmental factors and downstream signaling that cooperate with intrinsic genetic changes to drive metastasis. Understanding the interaction between extrinsic and intrinsic factors that regulate epithelial-mesenchymal plasticity will allow the development of new therapies that target tumor microenvironmental signals to reduce metastasis.
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Development of worker inhalation derived no effect levels for tungsten compounds.
J Toxicol Environ Health B Crit Rev
PUBLISHED: 05-21-2013
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Under the European Community (EC) Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH), the risk to humans may be considered controlled if the estimated exposure levels to a substance do not exceed the appropriate derived no-effect level (DNEL). In order to address worker exposure, DNELs are derived for the worker population. The most significant route of exposure to workers to both soluble and sparingly soluble tungsten substances is through inhalation. In order to meet the REACH registration requirements, occupational long-term inhalation DNELs were developed according to the European Chemical Agency (ECHA) REACH guidance on characterization of dose-response for human health. The inhalation DNELlong-term for sodium tungstate, from which all other soluble tungsten substance DNELs were derived, is 3 mg sodium tungstate/m(3) (1.7 mg W/m(3)), and the inhalation DNELlong-term for tungsten blue oxide, from which all other sparingly soluble tungsten substance DNELs were derived, is 7.3 mg tungsten blue oxide/m(3) (5.8 mg tungsten/m(3)). Although derived using different methodologies and supported by different studies, the occupational inhalation DNELslong-term for soluble and sparingly soluble tungsten compounds are similar to the current National Institute for Occupational Safety and Health (NIOSH) recommended exposure level (REL) and the American Conference of Industrial Hygienists (ACGIH) threshold limit value (TLV) 8-h time weighted average (TWA) of 1 mg tungsten/m(3) for soluble tungsten compounds and 5 mg tungsten/m(3) as metal and insoluble tungsten compounds.
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FAM83B-mediated activation of PI3K/AKT and MAPK signaling cooperates to promote epithelial cell transformation and resistance to targeted therapies.
Oncotarget
PUBLISHED: 05-17-2013
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Therapies targeting MAPK and AKT/mTOR signaling are currently being evaluated in clinical trials for several tumor types. However, recent studies suggest that these therapies may be limited due to acquired cancer cell resistance and a small therapeutic index between normal and cancer cells. The identification of novel proteins that are involved in MAPK or AKT/mTOR signaling and differentially expressed between normal and cancer cells will provide mechanistically distinct therapeutic targets with the potential to inhibit these key cancer-associated pathways. We recently identified FAM83B as a novel, previously uncharacterized oncogene capable of hyperactivating MAPK and mTOR signaling and driving the tumorigenicity of immortalized human mammary epithelial cells (HMEC). We show here that elevated FAM83B expression also activates the PI3K/AKT signaling pathway and confers a decreased sensitivity to PI3K, AKT, and mTOR inhibitors. FAM83B co-precipitated with the p85? and p110? subunits of PI3K, as well as AKT, and increased p110? and AKT membrane localization, consistent with elevated PI3K/AKT signaling. In tumor-derived cells harboring elevated FAM83B expression, ablation of FAM83B decreased p110? and AKT membrane localization, suppressed AKT phosphorylation, and diminished proliferation, AIG, and tumorigenicity in vivo. We propose that the level of FAM83B expression may be an important factor to consider when combined therapies targeting MAPK and AKT/mTOR signaling are used. Moreover, the identification of FAM83B as a novel oncogene and its integral involvement in activating PI3K/AKT and MAPK provides a foundation for future therapies aimed at targeting FAM83B in order to suppress the growth of PI3K/AKT- and MAPK-driven cancers.
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Production of microsclerotia by Brazilian strains of Metarhizium spp. using submerged liquid culture fermentation.
World J. Microbiol. Biotechnol.
PUBLISHED: 05-03-2013
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We investigated the potential production and desiccation tolerance of microsclerotia (MS) by Brazilian strains of Metarhizium anisopliae (Ma), M. acridum (Mc) and M. robertsii (Mr). These fungi were grown in a liquid medium containing 16 g carbon l(-1) with a carbon:nitrogen ratio of 50:1. One hundred milliliters cultures were grown in 250 ml Erlenmeyer flasks in a rotary incubator shaker at 28 °C and 200 rpm for 5 days. Five-day-old MS were harvested, mixed with diatomaceous earth (DE) and air-dried for 2 days at 30 °C. The air-dried MS-DE granular preparations were milled by mortar + pestle and stored in centrifuged tubes at either 26 or -20 °C. Desiccation tolerance and conidia production were assessed for dried MS granules by measuring hyphal germination after incubation for 2 days on water agar plates at 26 °C and for conidia production following 7 days incubation. Yields of MS by all strains of Metarhizium were 6.1-7.3 × 10(6) l(-1) after 3 days growth with maximum MS yields (0.7-1.1 × 10(7) l(-1)) after 5 days growth. No differences in biomass accumulation were observed after 3 days growth, whereas Ma-CG168 showed the highest biomass accumulation after 5 days growth. Dried MS-DE preparations of all fungal strains were equally tolerant to desiccation (?93 % germination) and the highest conidia production was obtained by MS granules of Mc-CG423 (4 × 10(9) conidia g(-1)). All MS granules showed similar stability after storage at either 26 or -20 °C for 3.5 months.
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Managing NIF safety equipment in a high neutron and gamma radiation environment.
Health Phys
PUBLISHED: 05-01-2013
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The National Ignition Facility (NIF) is a 192 laser beam facility that supports the Inertial Confinement Fusion program. During the ignition experimental campaign, the NIF is expected to perform shots with varying fusion yield producing 14 MeV neutrons up to 20 MJ or 7.1 × 10(18) neutrons per shot and a maximum annual yield of 1,200 MJ. Several infrastructure support systems will be exposed to varying high yield shots over the facilitys 30-y life span. In response to this potential exposure, analysis and testing of several facility safety systems have been conducted. A detailed MCNP (Monte Carlo N-Particle Transport Code) model has been developed for the NIF facility, and it includes most of the major structures inside the Target Bay. The model has been used in the simulation of expected neutron and gamma fluences throughout the Target Bay. Radiation susceptible components were identified and tested to fluences greater than 10(13) (n cm(-2)) for 14 MeV neutrons and ?-ray equivalent. The testing includes component irradiation using a 60Co gamma source and accelerator-based irradiation using 4- and 14- MeV neutron sources. The subsystem implementation in the facility is based on the fluence estimates after shielding and survivability guidelines derived from the dose maps and component tests results. This paper reports on the evaluation and implementation of mitigations for several infrastructure safety support systems, including video, oxygen monitoring, pressure monitors, water sensing systems, and access control interfaces found at the NIF.
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Efficacy of extended-release 45 mg oral minocycline and extended-release 45 mg oral minocycline plus 15% azelaic acid in the treatment of acne rosacea.
J Drugs Dermatol
PUBLISHED: 04-03-2013
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Rosacea is one of the most commonly occurring dermatoses treated by dermatologists. There are multiple therapeutic options available for the treatment of papulopustular rosacea. Rosacea is an inflammatory condition, classically presenting with flushing and/or blushing along with erythema, edema, telangiectasia, papules, pustules, and nodules of the face. Minocycline, a member of the tetracycline family, has demonstrated benefit in the treatment of inflammatory lesions in patients with rosacea. This manuscript highlights the use of a new sustained-release low-dose minocycline 45 mg tablet, with or without azelaic acid, for the treatment of papulopustular rosacea.
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Control of key pecan insect pests using biorational pesticides.
J. Econ. Entomol.
PUBLISHED: 03-02-2013
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Key pecan insect pests include the black pecan aphid, Melanocallis caryaefoliae (Davis), pecan weevil, Curculio caryae (Horn), and stink bugs (Hemiptera: Pentatomidae). Alternative control tactics are needed for management of these pests in organic and conventional systems. Our objective was to evaluate the potential utility of several alternative insecticides including three plant extract formulations, eucalyptus extract, citrus extract-8.92%, and citrus extract-19.4%, and two microbial insecticides, Chromobacterium subtsugae (Martin et al.) and Isaria fumosorosea (Wize). In the laboratory, eucalyptus extract, citrus extract-8.92%, citrus extract-19.4%, and C. subtsugae caused M. caryaefoliae mortality (mortality was reached approximately 78, 83, and 96%, respectively). In field tests, combined applications of I. fumosorosea with eucalyptus extract were synergistic and caused up to 82% mortality in M. caryaefoliae. In laboratory assays focusing on C. caryae suppression, C. subtsugae reduced feeding and oviposition damage, eucalyptus extract and citrus extract-19.4% were ineffective, and antagonism was observed when citrus extract-19.4% was combined with the entomopathogenic nematode, Steinernema carpocapsae (Weiser). In field tests, C. subtsugae reduced C. caryae damage by 55% within the first 3d, and caused 74.5% corrected mortality within 7 d posttreatment. In the laboratory, C. subtsugae and eucalyptus extract did not cause mortality in the brown stink bug, Euschistus servus (Say). Applications of C. subtsugae for suppression of C. caryae, and eucalyptus extract plus I. fumosorosea for control of M. caryaefoliae show promise as alternative insecticides and should be evaluated further.
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Efficacy of a granular formulation containing Metarhizium brunneum F52 (Hypocreales: Clavicipitaceae) microsclerotia against nymphs of Ixodes scapularis (Acari: Ixoididae).
J. Econ. Entomol.
PUBLISHED: 03-02-2013
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Technical improvements in the production and formulation of microbial agents will increase the potential for development of biological pesticides that are able to compete with chemical insecticides in the marketplace. Here we report the efficacy of a simple granule formulation containing microsclerotia of Metarhizium brunneum (Petch) (Hypocreales: Clavicipitaceae) for control of unfed and fed nymphs of Ixodes scpaularis Say (Acari: Ixoididae). Microsclerotial granules of M. brunneum applied to moist potting mix produce infective conidia within 2 wk and conidia remained viable for up to 8 wk after application. Microsclerotial granules produced from 3.05 x 10(9) to 1.24 x 10(10) conidia g(-1) granules in potting mix. Both unfed and fed nymphs were susceptible to infection when exposed to treated potting soil with up to 56 and 74% mortality, respectively. M. brunneum demonstrated a transtadial infection for fed nymphs exposed to treated potting mix with signs of a fungal infection becoming apparent only after molting into adults. High conidial production rates from microsclerotial granules of M. brunneum combined with significant tick mortality support the need for additional research to evaluate the efficacy of this treatment technology as a biopesticide option for control of ticks.
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Pathogenesis of growth failure and partial reversal with gene therapy in murine and canine Glycogen Storage Disease type Ia.
Mol. Genet. Metab.
PUBLISHED: 02-12-2013
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Glycogen Storage Disease type Ia (GSD-Ia) in humans frequently causes delayed bone maturation, decrease in final adult height, and decreased growth velocity. This study evaluates the pathogenesis of growth failure and the effect of gene therapy on growth in GSD-Ia affected dogs and mice. Here we found that homozygous G6pase (-/-) mice with GSD-Ia have normal growth hormone (GH) levels in response to hypoglycemia, decreased insulin-like growth factor (IGF) 1 levels, and attenuated weight gain following administration of GH. Expression of hepatic GH receptor and IGF 1 mRNAs and hepatic STAT5 (phospho Y694) protein levels are reduced prior to and after GH administration, indicating GH resistance. However, restoration of G6Pase expression in the liver by treatment with adeno-associated virus 8 pseudotyped vector expressing G6Pase (AAV2/8-G6Pase) corrected body weight, but failed to normalize plasma IGF 1 in G6pase (-/-) mice. Untreated G6pase (-/-) mice also demonstrated severe delay of growth plate ossification at 12 days of age; those treated with AAV2/8-G6Pase at 14 days of age demonstrated skeletal dysplasia and limb shortening when analyzed radiographically at 6 months of age, in spite of apparent metabolic correction. Moreover, gene therapy with AAV2/9-G6Pase only partially corrected growth in GSD-Ia affected dogs as detected by weight and bone measurements and serum IGF 1 concentrations were persistently low in treated dogs. We also found that heterozygous GSD-Ia carrier dogs had decreased serum IGF 1, adult body weights and bone dimensions compared to wild-type littermates. In sum, these findings suggest that growth failure in GSD-Ia results, at least in part, from hepatic GH resistance. In addition, gene therapy improved growth in addition to promoting long-term survival in dogs and mice with GSD-Ia.
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Constitutive CCND1/CDK2 activity substitutes for p53 loss, or MYC or oncogenic RAS expression in the transformation of human mammary epithelial cells.
PLoS ONE
PUBLISHED: 02-04-2013
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Cancer develops following the accumulation of genetic and epigenetic alterations that inactivate tumor suppressor genes and activate proto-oncogenes. Dysregulated cyclin-dependent kinase (CDK) activity has oncogenic potential in breast cancer due to its ability to inactivate key tumor suppressor networks and drive aberrant proliferation. Accumulation or over-expression of cyclin D1 (CCND1) occurs in a majority of breast cancers and over-expression of CCND1 leads to accumulation of activated CCND1/CDK2 complexes in breast cancer cells. We describe here the role of constitutively active CCND1/CDK2 complexes in human mammary epithelial cell (HMEC) transformation. A genetically-defined, stepwise HMEC transformation model was generated by inhibiting p16 and p53 with shRNA, and expressing exogenous MYC and mutant RAS. By replacing components of this model, we demonstrate that constitutive CCND1/CDK2 activity effectively confers anchorage independent growth by inhibiting p53 or replacing MYC or oncogenic RAS expression. These findings are consistent with several clinical observations of luminal breast cancer sub-types that show elevated CCND1 typically occurs in specimens that retain wild-type p53, do not amplify MYC, and contain no RAS mutations. Taken together, these data suggest that targeted inhibition of constitutive CCND1/CDK2 activity may enhance the effectiveness of current treatments for luminal breast cancer.
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c-MYC functions as a molecular switch to alter the response of human mammary epithelial cells to oncostatin M.
Cancer Res.
PUBLISHED: 10-05-2011
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Cytokines play an important role in creating an inflammatory microenvironment, which is now considered a hallmark of cancer. Although tumor cells can exploit cytokine signaling to promote growth, invasion, and metastasis, the response of normal and premalignant epithelial cells to cytokines present in a developing tumor microenvironment remains unclear. Oncostatin M (OSM), an IL-6 family cytokine responsible for STAT3 activation, has been implicated in cancer development, progression, invasion, and metastasis. Paradoxically, OSM can also suppress the growth of normal cells and certain tumor-derived cell lines. Using isogenic human mammary epithelial cells (HMEC) at different stages of neoplastic transformation, we found that OSM signaling suppressed c-MYC expression and engaged a p16- and p53-independent growth arrest that required STAT3 activity. Inhibition of STAT3 activation by expressing a dominant-negative STAT3 protein or a STAT3-shRNA prevented the OSM-mediated arrest. In addition, expression of c-MYC from a constitutive promoter also abrogated the STAT3-mediated arrest, and strikingly, cooperated with OSM to promote anchorage-independent growth (AIG), a property associated with malignant transformation. Cooperative transformation by c-MYC and OSM required PI3K and AKT signaling, showing the importance of multiple signaling pathways downstream of the OSM receptor in defining the cellular response to cytokines. These findings identify c-MYC as an important molecular switch that alters the cellular response to OSM-mediated signaling from tumor suppressive to tumor promoting.
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Neurotoxicity following acute inhalation exposure to the oil dispersant COREXIT EC9500A.
J. Toxicol. Environ. Health Part A
PUBLISHED: 09-16-2011
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Consequent to the 2010 Deepwater Horizon oil spill in the Gulf of Mexico, there is an emergent concern about the short- and long-term adverse health effects of exposure to crude oil, weathered-oil products, and oil dispersants among the workforce employed to contain and clean up the spill. Oil dispersants typically comprise of a mixture of solvents and surfactants that break down floating oil to micrometer-sized droplets within the water column, thus preventing it from reaching the shorelines. As dispersants are generally sprayed from the air, workers are at risk for exposure primarily via inhalation. Such inhaled fractions might potentially permeate or translocate to the brain via olfactory or systemic circulation, producing central nervous system (CNS) abnormalities. To determine whether oil dispersants pose a neurological risk, male Sprague-Dawley rats were exposed by whole-body inhalation exposure to a model oil dispersant, COREXIT EC9500A (CE; approximately 27 mg/m(3) × 5 h/d × 1 d), and various molecular indices of neural dysfunction were evaluated in discrete brain areas, at 1 or 7 d postexposure. Exposure to CE produced partial loss of olfactory marker protein in the olfactory bulb. CE also reduced tyrosine hydroxylase protein content in the striatum. Further, CE altered the levels of various synaptic and neuronal intermediate filament proteins in specific brain areas. Reactive astrogliosis, as evidenced by increased expression of glial fibrillary acidic protein, was observed in the hippocampus and frontal cortex following exposure to CE. Collectively, these findings are suggestive of disruptions in olfactory signal transduction, axonal function, and synaptic vesicle fusion, events that potentially result in an imbalance in neurotransmitter signaling. Whether such acute molecular aberrations might persist and produce chronic neurological deficits remains to be ascertained.
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Acute effects of COREXIT EC9500A on cardiovascular functions in rats.
J. Toxicol. Environ. Health Part A
PUBLISHED: 09-16-2011
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These studies characterized cardiovascular responses after an acute inhalation exposure to COREXIT EC9500A, the oil dispersant used in the Deepwater Horizon oil spill. Male Sprague-Dawley rats underwent a single 5-h inhalation exposure to COREXIT EC9500A (average exposure level 27.12 mg/m(3)) or air. On d 1 and 7 following the exposure, rats were implanted with indwelling catheters and changes in heart rate and blood pressure were assessed in response to increasing levels of adrenoreceptor agonists. A separate group of rats was euthanized at the same time points, ventral tail arteries were dissected, and vascular tone along with dose-dependent responses to vasoconstricting and dilating factors were assessed in vitro. Agonist-induced dose-dependent increases in heart rate and blood pressure were greater in COREXIT EC9500A-exposed than in air-exposed rats at 1 d but not 7 d after the exposure. COREXIT EC9500A exposure also induced a rise in basal tone and reduced responsiveness of tail arteries to acetylcholine-induced vasodilation at 1 d but not 7 d following the exposure. These findings demonstrate that an acute exposure to COREXIT EC9500A exerts transient effects on cardiovascular and peripheral vascular functions.
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Pulmonary effects after acute inhalation of oil dispersant (COREXIT EC9500A) in rats.
J. Toxicol. Environ. Health Part A
PUBLISHED: 09-16-2011
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COREXIT EC9500A (COREXIT) was used to disperse crude oil during the 2010 Deepwater Horizon oil spill. While the environmental impact of COREXIT has been examined, the pulmonary effects are unknown. Investigations were undertaken to determine whether inhaled COREXIT elicits airway inflammation, alters pulmonary function or airway reactivity, or exerts pharmacological effects. Male rats were exposed to COREXIT (mean 27 mg/m(3), 5 h). Bronchoalveolar lavage was performed on d 1 and 7 postexposure. Lactate dehydrogenase (LDH) and albumin were measured as indices of lung injury; macrophages, neutrophils, lymphocytes, and eosinophils were quantified to evaluate inflammation; and oxidant production by macrophages and neutrophils was measured. There were no significant effects of COREXIT on LDH, albumin, inflammatory cell levels or oxidant production at either time point. In conscious animals, neither breathing frequency nor specific airway resistance were altered at 1 hr, 1 d and 7 d postexposure. Airway resistance responses to methacholine (MCh) aerosol in anesthetized animals were unaffected at 1 and 7 d postexposure, while dynamic compliance responses were decreased after 1 d but not 7 d. In tracheal strips, in the presence or absence of MCh, low concentrations of COREXIT (0.001% v/v) elicited relaxation; contraction occurred at 0.003-0.1% v/v. In isolated, perfused trachea, intraluminally applied COREXIT produced similar effects but at higher concentrations. COREXIT inhibited neurogenic contractile responses of strips to electrical field stimulation. Our findings suggest that COREXIT inhalation did not initiate lung inflammation, but may transiently increase the difficulty of breathing.
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A computer-controlled whole-body inhalation exposure system for the oil dispersant COREXIT EC9500A.
J. Toxicol. Environ. Health Part A
PUBLISHED: 09-16-2011
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An automated whole-body inhalation exposure system capable of exposing 12 individually housed rats was designed to examine the potential adverse health effects of the oil dispersant COREXIT EC9500A, used extensively during the Deepwater Horizon oil spill. A computer-controlled syringe pump injected the COREXIT EC9500A into an atomizer where droplets and vapor were formed and mixed with diluent air. The aerosolized COREXIT EC9500A was passed into a customized exposure chamber where a calibrated light-scattering instrument estimated the real-time particle mass concentration of the aerosol in the chamber. Software feedback loops controlled the chamber aerosol concentration and pressure throughout each exposure. The particle size distribution of the dispersant aerosol was measured and shown to have a count median aerodynamic diameter of 285 nm with a geometric standard deviation of 1.7. The total chamber concentration (particulate + vapor) was determined using a modification of the acidified methylene blue spectrophotometric assay for anionic surfactants. Tests were conducted to show the effectiveness of closed loop control of chamber concentration and to verify chamber concentration homogeneity. Five automated 5-h animal exposures were performed that produced controlled and consistent COREXIT EC9500A concentrations (27.1 ± 2.9 mg/m(3), mean ± SD).
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Non-healing leg ulcers in a patient with dystrophic calcification and crest syndrome: a challenging clinical case.
Int Wound J
PUBLISHED: 08-09-2011
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The management of non-healing leg ulcers in patients with CREST syndrome and subdermal calcification is rarely reported in medical literature. Only one similar case was found in the literature (1). Dealing with such patients can be a challenge for wound specialists. In this article, we discuss the clinical progress of an interesting case of extensive non-healing leg ulcers in a CREST patient with dystrophic calcification. The combination of systemic physiological deficits and immune compromise, along with the local physical abnormalities associated with the wound pose a complex multifactorial aetiological mix. There is no conclusive data on the optimal management of these wounds in CREST patients. It seems that ablation of the calcific deposits may offer some hope.
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Topical rosacea therapy: the importance of vehicles for efficacy, tolerability and compliance.
J Drugs Dermatol
PUBLISHED: 06-04-2011
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Many topical medications are available for the treatment of papulopustular rosacea. While treatments contain metronidazole, azelaic acid, or sodium sulfacetamide-sulfur as the active ingredient, the composition of the vehicle formulations varies widely. These vehicles come in gels, creams, lotions and foams; some ingredients are common to many vehicles, while some vehicles contain unique ingredients designed to optimize skin penetration and delivery of the active drug to its target. Vehicles can also influence tolerability, which is always a concern in patients with heightened skin sensitivity, and compliance, which is typically lower for topical treatments than oral treatments. Ideally, the vehicle of any rosacea treatment should enhance drug delivery, be nonirritating and be easy to use. Ingredients that help repair barrier function are also desirable. This review will focus on the key components of the vehicles from the most commonly used topical therapies for papulopustular rosacea and how vehicle formulations influence the delivery of active ingredient, skin barrier repair, tolerability and compliance.
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TGF-beta signaling engages an ATM-CHK2-p53-independent RAS-induced senescence and prevents malignant transformation in human mammary epithelial cells.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 05-09-2011
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Oncogene-induced senescence (OIS), the proliferative arrest engaged in response to persistent oncogene activation, serves as an important tumor-suppressive barrier. We show here that finite lifespan human mammary epithelial cells (HMEC) undergo a p16/RB- and p53-independent OIS in response to oncogenic RAS that requires TGF-? signaling. Suppression of TGF-? signaling by expression of a dominant-negative TGF-? type II receptor, use of a TGF-? type I receptor inhibitor, or ectopic expression of MYC permitted continued proliferation upon RAS expression. Surprisingly, unlike fibroblasts, shRNA-mediated knockdown of ATM or CHK2 was unable to prevent RAS-mediated OIS, arguing that the DNA damage response is not required for OIS in HMEC. Abrogation of TGF-? signaling not only allowed HMEC lacking p53 to tolerate oncogenic RAS but also conferred the capacity for anchorage-independent growth. Thus, the OIS engaged after dysregulated RAS expression provides an early barrier to malignant progression and is mediated by TGF-? receptor activation in HMEC. Understanding the mechanisms that initiate and maintain OIS in epithelial cells may provide a foundation for future therapies aimed at reengaging this proliferative barrier as a cancer therapy.
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A comparison of covered vs bare expandable stents for the treatment of aortoiliac occlusive disease.
J. Vasc. Surg.
PUBLISHED: 02-19-2011
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This trial was conducted to determine if covered stents offer a patency advantage over bare-metal stents in the treatment of aortoiliac arterial occlusive disease.
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Determining when enhanced pause (Penh) is sensitive to changes in specific airway resistance.
J. Toxicol. Environ. Health Part A
PUBLISHED: 01-18-2011
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Penh is a dimensionless index normally used to evaluate changes in the shape of the airflow pattern entering and leaving a whole-body flow plethysmograph as an animal breathes. The index is sensitive to changes in the distribution of area under the waveform during exhalation and increases in a nonlinear fashion as the normalized area increases near the beginning of the curve. Enhanced pause (Penh) has been used to evaluate changes in pulmonary function and as a method to evaluate airway reactivity. However, the use of Penh to assess pulmonary function has been challenged (Bates et al., 2004; Lundblad et al., 2002; Mitzner et al., 2003; Mitzner & Tankersley, 1998; Petak et al., 2001; Sly et al., 2005). The objective of this study was to show how Penh of the thorax and plethysmograph flow patterns are related. That relationship is used to describe the conditions under which whole-body plethysmograph Penh measurements can be used to detect changes in sRaw.
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A rare presentation of spinal epidural abscess.
BMJ Case Rep
PUBLISHED: 01-01-2011
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A 77-year-old retired engineer presented to accident and emergency with deteriorating shortness of breath that had been troubling him for several months. At that time, he was being investigated by a chest physician who had identified bilateral diaphragmatic paralysis on ultrasound and was awaiting further imaging. Clinical assessment and nerve conduction studies on this admission were compatible with a diagnosis of motor neuron disease but specialist neurology input recommended an MRI to rule out cord pathology. This proved problematic as the patient was non-invasive ventilation dependent and unable to lay supine as this further compromised his respiratory function. To ensure that a potentially reversible cause for his symptoms was identified, the patient was intubated for an MRI which subsequently demonstrated multi level spinal epidural empyema. The benefits of neurosurgical intervention were judged to be uncertain at best, and following discussion with the family, active care was withdrawn. The patient passed away shortly thereafter.
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Nanoparticles-containing spray can aerosol: characterization, exposure assessment, and generator design.
Inhal Toxicol
PUBLISHED: 10-12-2010
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This is the first report demonstrating that a commercially available household consumer product produces nanoparticles in a respirable range. This report describes a method developed to characterize nanoparticles that were produced under typical exposure conditions when using a consumer spray product. A well-controlled indoor environment was simulated for conducting spray applications approximating a human exposure scenario. Results indicated that, while aerosol droplets were large with a count median diameter of 22 µm during spraying, the final aerosol contained primarily solid TiO(2) particles with a diameter of 75 nm. This size reduction was due to the surface deposition of the droplets and the rapid evaporation of the aerosol propellant. In the breathing zone, the aerosol, containing primarily individual particles (>90%), had a mass concentration of 3.4 mg/m(3), or 1.6 × 10(5) particles/cm(3), with a nanoparticle fraction limited to 170 µg/m(3), or 1.2 × 10(5) particles/cm(3). The results were used to estimate the pulmonary dose in an average human (0.075 µg TiO(2) per m(2) alveolar epithelium per minute) and rat (0.03 µg TiO(2)) and, consequently, this information was used to design an inhalation exposure system. The system consisted of a computer-controlled solenoid finger for generating constant concentrations of spray can aerosols inside a chamber. Test results demonstrated great similarity between the solenoid finger-dispersed aerosol compared to human-generated aerosol. Future investigations will include an inhalation study to obtain information on dose-response relationships in rats and to use it to establish a No Effect Exposure Level for setting guidelines for this consumer product.
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Hypercalcaemia Mimicking STEMI on Electrocardiography.
Case Rep Med
PUBLISHED: 09-30-2010
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Acute coronary syndrome is a common cause of presentation to hospital. ST segment elevation on an electrocardiogram (ECG) is likely to be cardiac in origin, but in low-risk patients other causes must be ruled out. We describe a case of a man with hypercalcaemia, no evidence of cardiac disease, and ECG changes mimicking acute myocardial infarction. These ECG changes resolved after treatment of the hypercalcaemia.
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A soluble acid invertase is directed to the vacuole by a signal anchor mechanism.
J. Plant Physiol.
PUBLISHED: 08-26-2010
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Enzyme activities in the vacuole have an important impact on the net concentration of sucrose. In sugarcane (Saccharum hybrid), immunolabelling demonstrated that a soluble acid invertase (?-fructofuranosidase; EC 3.2.1.26) is present in the vacuole of storage parenchyma cells during sucrose accumulation. Examination of sequences from sugarcane, barley and rice showed that the N-terminus of the invertase sequence contains a signal anchor and a tyrosine motif, characteristic of single-pass membrane proteins destined for lysosomal compartments. The N-terminal peptide from the barley invertase was shown to be capable of directing the green fluorescent protein to the vacuole in sugarcane cells. The results suggest that soluble acid invertase is sorted to the vacuole in a membrane-bound form.
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Vision specific quality of life of pediatric contact lens wearers.
Optom Vis Sci
PUBLISHED: 06-22-2010
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Several studies have shown that children are capable of wearing and caring for contact lenses, but it is not known whether the benefits outweigh the risks associated with contact lens wear. The purpose of this article is to compare the vision-related quality of life benefits of children randomized to wear spectacles or contact lenses for 3 years using the Pediatric Refractive Error Profile.
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A comparison of spectacle and contact lens wearing times in the ACHIEVE study.
Clin Exp Optom
PUBLISHED: 06-19-2010
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The aim was to compare vision correction wearing time between myopic children and teenagers in a clinical trial of contact lenses and spectacles.
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Mycophenolate mofetil for the treatment of chronic dermatitis: an open-label study of 16 patients.
J Drugs Dermatol
PUBLISHED: 06-03-2010
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Chronic dermatitis that is refractory to topical therapy poses a difficult treatment problem. Many patients are corticosteroid dependent. Mycophenolate mofetil (MMF) is a systemic B- and T-cell inhibitor that has some effect on delayed-type hypersensitivity. DESIGN, SETTING, INTERVENTIONS: In this open-label study conducted in a university-affiliated private practice setting, 16 patients with chronic and refractory eczema of three months duration or longer were enrolled consecutively into one of three cohorts based on dosage of MMF: five at 1 g/d, six at 1.5 g/d and five at 2.0 g/d. Patients in each cohort were allowed to increase dosage to a maximum of 3 g/d during the study. The authors evaluated the improvement of eczema and the presence of side effects over a 34-week period. Trends in patient and investigator global assessments were analyzed with the fitting of models using generalized estimating equations (GEE).
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The effect of obesity on the outcome of hip and knee arthroplasty.
Int Orthop
PUBLISHED: 04-18-2010
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The aim of this study was to evaluate the outcome of joint arthroplasty in obese and non-obese patients. We reviewed 2,026 consecutive primary total hip and 535 primary total knee arthroplasties performed for osteoarthritis. Patients were separated into two groups according to their body mass index (BMI): non-obese (BMI < 30) and obese (BMI ? 30). Their survivorships were compared. Case controlled studies were performed with 134 hip and 50 knee arthroplasties in obese patients. Each was matched individually with a control and their outcome compared. Log rank tests for equality of survival showed no difference in the survival for hip and knee arthroplasty at 11 and ten years, respectively. The obese group had significantly lower postoperative hip and knee scores at latest follow-up, especially in the range of motion. Overall patient satisfaction scores were comparable. There were no significant differences in the radiographic analysis of both hip and knee implants. Revision was used as an end point for the survival analysis. Functional scores (Harris hip score and Hospital for Special Surgery knee score), satisfaction for surgery and radiographic features were used as outcome measures for comparison. The mid-term survival of total hip and knee arthroplasty is not adversely affected by obesity. Despite lower clinical scores, the obese patients were satisfied with the results of their surgery and have an equivalent mid-term survival rate. It would be unreasonable to deny patients arthroplasty surgery purely on the basis of a BMI indicating obesity.
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Inactivation of p53 signaling by p73 or PTEN ablation results in a transformed phenotype that remains susceptible to Nutlin-3 mediated apoptosis.
Cell Cycle
PUBLISHED: 04-01-2010
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The p53 signaling pathway is frequently disrupted in carcinogenesis. However, roughly 50% of all cancers express wild-type p53 and have alterations in accessory signaling components required for p53 activity. Using the well described E1A/RAS transformation model, in which p53 activity must be suppressed for transformation, we show here that p53 is inactive and unable to suppress transformation following ablation of p73 or PTEN. However, despite the transformed phenotype conferred by p53 inactivation following p73 or PTEN loss, p53 could be fully activated by Nutlin-3, resulting in efficient caspase-mediated apoptosis. Our novel and unexpected finding provides important information regarding the efficacy of Nutlin-3 and indicates that patients with tumors deficient in p53 function due to p73 or PTEN loss may benefit from Nutlin-3 treatment.
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Canine angiostrongylosis: an emerging disease in Europe.
J Vet Emerg Crit Care (San Antonio)
PUBLISHED: 03-17-2010
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The aim of this article is to review Angiostrongylus vasorum infection in dogs, including the life cycle, signalment, clinical signs, diagnosis, and treatment. Apparent changes in the epidemiology of this unique parasite are considered, alongside information available regarding its recent geographic spread.
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Complications of definitive open reduction and internal fixation of pilon fractures of the distal tibia.
Int Orthop
PUBLISHED: 03-12-2010
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A series of 49 pilon fractures in a tertiary referral centre treated definitively by open reduction and internal fixation have been assessed and the complications of such injuries examined. A retrospective analysis of case notes, radiographs and computerised tomographs over a seven-year period from 1999-2006 was performed. Infection was the most common postoperative problem. There were seven cases of superficial infection. There was a single case of deep infection requiring intravenous antibiotics and removal of metalwork. Other notable complications were those of secondary osteoarthritis (three cases) and malunion (one case). The key finding of this paper is the 2% incidence of deep infection following the direct operative approach to these fractures. The traditional operative approach to such injuries (initially advocated by Rüedi and Allgöwer in Injury 2:92-99, 1969) consisted of extensive soft tissue dissection to gain access to the distal tibia. Our preferred method is to access the tibia via the "direct approach" which involves direct access to the fracture site with minimal disturbance of the soft tissue envelope. We therefore believe that open reduction and internal fixation of pilon fractures via the direct approach to be a safe technique in the treatment of such devastating injuries.
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A randomized, investigator-blinded trial to assess the antimicrobial efficacy of a benzoyl peroxide 5%/ clindamycin phosphate 1% gel compared with a clindamycin phosphate 1.2%/tretinoin 0.025% gel in the topical treatment of acne vulgaris.
J Drugs Dermatol
PUBLISHED: 03-11-2010
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Combination products in which the individual components have different mechanisms of antimicrobial action have been shown in many disease states to provide the most effective therapy.
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Evaluation of fire-safety programs that use 10-year smoke alarms.
J Community Health
PUBLISHED: 02-24-2010
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The Centers for Disease Control and Prevention began funding a Smoke Alarm Installation and Fire Safety Education (SAIFE) program in 1998. This program involves the installation of lithium-powered "10-year" smoke alarms in homes at high risk for fires and injuries. This study aimed to (1) determine among original SAIFE homes if the lithium-powered alarms were still present and functional 8-10 years after installation and (2) understand factors related to smoke alarm presence and functionality. Data on a total of 384 homes and 601 smoke alarms in five states were collected and analyzed. Only one-third of alarms were still functional; 37% of installed alarms were missing; and 30% of alarms were present, but not functioning. Alarms were less likely to be functioning if they were installed in the kitchen and if homes had a different resident at follow-up. Of the 351 alarms that were present and had a battery at the time of the evaluation, only 21% contained lithium-powered batteries. Of these, 78% were still functioning. Programs that install lithium-powered alarms should use units that have sealed-in batteries and "hush" buttons. Additionally, education should be given on smoke alarm maintenance that includes a message that batteries in these alarms should not be replaced. Lithium-powered smoke alarms should last up to 10 years if maintained properly.
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p53-Dependent p21-mediated growth arrest pre-empts and protects HCT116 cells from PUMA-mediated apoptosis induced by EGCG.
Cancer Lett.
PUBLISHED: 02-03-2010
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The tumor suppressor protein p53 plays a key role in regulation of negative cellular growth in response to EGCG. To further explore the role of p53 signaling and elucidate the molecular mechanism, we employed colon cancer HCT116 cell line and its derivatives in which a specific transcriptional target of p53 is knocked down by homologous recombination. Cells expressing p53 and p21 accumulate in G1 upon treatment with EGCG. In contrast, same cells lacking p21 traverse through the cell cycle and eventually undergo apoptosis as revealed by TUNEL staining. Treatment with EGCG leads to induction of p53, p21 and PUMA in p21 wild-type, and p53 and PUMA in p21(-/-) cells. Ablation of p53 by RNAi protects p21(-/-) cells, thus indicating a p53-dependent apoptosis by EGCG. Furthermore, analysis of cells lacking PUMA or Bax with or without p21 but with p53 reveals that all the cells expressing p53 and p21 survived after EGCG treatment. More interestingly, cells lacking both PUMA and p21 survived ECGC treatment whereas those lacking p21 and Bax did not. Taken together, our results present a novel concept wherein p21-dependent growth arrest pre-empts and protects cells from otherwise, in its absence, apoptosis which is mediated by activation of pro-apoptotic protein PUMA. Furthermore, we find that p53-dependent activation of PUMA in response to EGCG directly leads to apoptosis with out requiring Bax as is the case in response to agents that induce DNA damage. p21, thus can be used as a molecular switch for therapeutic intervention of colon cancer.
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Restoration of p53 functions protects cells from concanavalin A-induced apoptosis.
Mol. Cancer Ther.
PUBLISHED: 02-02-2010
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A great majority of human cancers encounter disruption of the p53 network. Identification and characterization of molecular components important in both p53-dependent and p53-independent apoptosis might be useful in developing novel therapies. Previously, we reported that concanavalin A (Con A) induced p73-dependent apoptosis of cells lacking functional p53. In the present study, we investigated the mechanism and role of p53 in protection from apoptosis induced by Con A. Treatment with Con A resulted in apoptosis of p53-null ovarian cancer, SKOV3, or Li-Fraumeni syndrome, MDAH041 (041), cells. However, their isogenic pairs, SKP53 and TR9-7, expressing wild-type p53 were much less sensitive and were protected by G(1) arrest. Inhibition of p53 function rendered these cells sensitive to Con A. Con A-induced apoptosis was accompanied by upregulation of forkhead box O1a (FOXO1a) and Bcl-2-interacting mediator (Bim), which were strongly inhibited after p53 expression and rescued after p53 ablation. Moreover, ablation of Bim by short hairpin RNA protected cells from apoptosis. Taken together, our study suggests that Con A induces apoptosis of cells lacking p53 by activating FOXO1a-Bim signaling and that expression of p53 protects these cells by inducing G(1) arrest and by downregulating the expression of both FOXO1a and Bim, identifying a novel cross-talk between FOXO1a and p53 transcription factors.
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Posttraumatic proximal tibial growth arrest: a rare injury managed successfully with ring fixators.
J Pediatr Orthop B
PUBLISHED: 01-22-2010
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A ring fixator was used in the treatment of five patients (ages 11 to 16 years) with proximal tibial growth arrest after trauma. The mean corrections were 14.2 degrees (maximum 28 degrees , minimum 0 degrees ) in the saggital plane and 14 degrees (maximum 38 degrees , minimum 2 degrees ) in the coronal plane. Leg length discrepancy was also corrected (max 1 cm). The average time in frame was 17.8 weeks, with an average correction time of 29.8 days. Knee Society Clinical Rating System scores post operatively ranged from 95-100. All patients returned to full activity, and would accept the same treatment if offered again. The circular fixator is an effective, minimally invasive method for treating the complex deformities arising from this rare injury. Patients remain active during treatment, encouraging a rapid return to school/work activities.
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Regulation of NF-kappaB by NSD1/FBXL11-dependent reversible lysine methylation of p65.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 12-22-2009
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NF-kappaB, a central coordinator of immune and inflammatory responses, must be tightly regulated. We describe a NF-kappaB regulatory pathway that is driven by reversible lysine methylation of the p65 subunit, carried out by a lysine methylase, the nuclear receptor-binding SET domain-containing protein 1 (NSD1), and a lysine demethylase, F-box and leucine-rich repeat protein 11 (FBXL11). Overexpression of FBXL11 inhibits NF-kappaB activity, and a high level of NSD1 activates NF-kappaB and reverses the inhibitory effect of FBXL11, whereas reduced expression of NSD1 decreases NF-kappaB activation. The targets are K218 and K221 of p65, which are methylated in cells with activated NF-kappaB. Overexpression of FBXL11 slowed the growth of HT29 cancer cells, whereas shRNA-mediated knockdown had the opposite effect, and these phenotypes were dependent on K218/K221 methylation. In mouse embryo fibroblasts, the activation of most p65-dependent genes relied on K218/K221 methylation. Importantly, expression of the FBXL11 gene is driven by NF-kappaB, revealing a negative regulatory feedback loop. We conclude that reversible lysine methylation of NF-kappaB is an important element in the complex regulation of this key transcription factor.
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Overexpression of kinesins mediates docetaxel resistance in breast cancer cells.
Cancer Res.
PUBLISHED: 09-29-2009
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Resistance to chemotherapy remains a major barrier to the successful treatment of cancer. To understand mechanisms underlying docetaxel resistance in breast cancer, we used an insertional mutagenesis strategy to identify proteins whose overexpression confers resistance. A strong promoter was inserted approximately randomly into the genomes of tumor-derived breast cancer cells, using a novel lentiviral vector. We isolated a docetaxel-resistant clone in which the level of the kinesin KIFC3 was elevated. When KIFC3 or the additional kinesins KIFC1, KIF1A, or KIF5A were overexpressed in the breast cancer cell lines MDA-MB231 and MDA-MB 468, the cells became more resistant to docetaxel. The binding of kinesins to microtubules opposes the stabilizing effect of docetaxel that prevents cytokinesis and leads to apoptosis. Our finding that kinesins can mediate docetaxel resistance might lead to novel therapeutic approaches in which kinesin inhibitors are paired with taxanes.
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Identification of the minimal copper(II)-binding alpha-synuclein sequence.
Inorg Chem
PUBLISHED: 09-29-2009
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Parkinsons disease has been long linked to environmental factors, such as transition metals and recently to alpha-synuclein, a presynaptic protein. Using tryptophan-containing peptides, we identified the minimal Cu(II)-binding sequence to be within the first four residues, MDV(F/W), anchored by the alpha-amino terminus. In addition, mutant peptide 1-10 (Lys --> Arg) verified that neither Lys6 nor Lys10 are necessary for Cu(II) binding. Interestingly, Trp4 excited-state decay kinetics measured for peptides and proteins reveal two quenching modes, possibly arising from two distinct Cu(II)-polypeptide structures.
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The C-terminus of interferon gamma receptor beta chain (IFNgammaR2) has antiapoptotic activity as a Bax inhibitor.
Cancer Biol. Ther.
PUBLISHED: 09-20-2009
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Bax is a pro-apoptotic protein that mediates intrinsic cell-death signaling. Using a yeast-based functional screening approach, we identified interferon gamma receptor beta chain (IFNgammaR2) as a new Bax suppressor. IFNgammaR2 is a component of the IFNgamma receptor complex along with the IFNgammaR alpha chain (IFNgammaR1). Upon IFNgamma binding, a conformational change in the receptor complex occurs that activates the Jak2/STAT1 signaling cascade. We found that the C-terminal region (amino acids 296-337) of IFNgammaR2 (IFNgammaR2(296-337)) contains a novel Bax inhibitory domain. This portion does not contain the Jak2-binding domain; therefore, the antiapoptotic function of IFNgammaR2 is independent of JAK/STAT signaling. IFNgammaR2(296-337) rescued human cells from apoptosis induced by overexpression of Bax but not Bak. Overexpression of IFNgammaR2 (wild type and IFNgammaR2(296-337)) rescued cells from etoposide and staurosporine, which are known to induce Bax-mediated cell death. Interestingly, IFNgammaR2 inhibited apoptosis induced by the BH3-only protein Bim-EL, suggesting that IFNgammaR2 inhibits Bax activation through a BH3-only protein. Bax and IFNgammaR2 were co-immunoprecipitated from cell lysates prepared from HEK293 and DAMI cells. Furthermore, direct binding of purified recombinant proteins of Bax and IFNgammaR2 was also confirmed. Addition of recombinant Bcl-2 protein to cell lysates significantly reduced the interaction of IFNgammaR2 and Bax, suggesting that Bcl-2 and IFNgammaR2 bind a similar domain of Bax. We found that the C-terminal fragment (cytoplasmic domain) of IFNgammaR2 is expressed in human cancer cell lines of megakaryocytic cancer (DAMI), breast cancer (MDA-MD-468), and prostate cancer (PC3 cells). The presence of the C-terminal fragment of IFNgammaR2 may confer on cancer cells resistance to apoptotic stresses. Our discovery of the anti-Bax activity of the cytoplasmic domain of IFNgammaR2 may shed new light on the mechanism of how cell death is controlled by IFNgamma and Bax.
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Orbitofrontal and anterior cingulate cortex neurons selectively process cocaine-associated environmental cues in the rhesus monkey.
J. Neurosci.
PUBLISHED: 09-18-2009
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Encounters with stimuli associated with drug use are believed to contribute to relapse. To probe the neurobiology of environmentally triggered drug use, we have conducted single-unit recordings in rhesus monkeys during presentation of two distinct types of drug paired cues that differentially support drug-seeking. The animals were highly conditioned to these cues via exposure during self-administration procedures conducted over a 4 year period. The cues studied were a discriminative cue that signaled response-contingent availability of cocaine, and a discrete cue that was temporally paired with the cocaine infusion (0.1 or 0.5 mg/kg). Two cortical regions consistently activated by cocaine-associated cues in human imaging studies are the orbitofrontal (OFC) and anterior cingulate cortex (ACC), though little is known about cortical neuronal activity responses to drug cues. We simultaneously recorded single-unit activity in OFC and ACC as well as in dorsal striatum in rhesus monkeys during cocaine self-administration. Dorsal striatal neurons were less engaged by drug cues than cortical regions. Between OFC and ACC, distinct functionality was apparent in neuronal responses. OFC neurons preferentially responded to the discriminative cue, consistent with a role in cue-induced drug-seeking. In contrast, the ACC did not respond more to the discriminative cue than to the discrete cue. Also distinct from the OFC, ACC showed sustained firing throughout the 18 s duration of the discrete cue. This pattern of sustained activation in ACC is consistent with a role in reward expectation and/or in mediating behavioral effects of discrete cues paired with drug infusions.
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Validation-based insertional mutagenesis identifies lysine demethylase FBXL11 as a negative regulator of NFkappaB.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 09-01-2009
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We describe a highly efficient use of lentiviral validation-based insertional mutagenesis (VBIM) to generate large populations of mammalian cells in which a strong promoter is inserted into many different genomic loci, causing greatly increased expression of downstream sequences. Many different selections or screens can follow, to isolate dominant mutant clones with a desired phenotypic change. The inserted promoter can be excised or silenced at will, to prove that the insertion caused the mutation. Cloning DNA flanking the insertion site identifies the locus precisely. VBIM virus particles are pseudotyped with VSV G protein, allowing efficient infection of most mammalian cell types, including non-dividing cells, and features are included that give high yields of stable virus stocks. In several different selections, useful mutants have been obtained at frequencies of approximately 10(-6) or higher. We used the VBIM technique to isolate mutant human cells in which the F-box leucine-rich protein 11 (FBXL11), a histone H3K36 demethylase, is shown to be a negative regulator of NFkappaB. High levels of FBXL11 block the ability of NFkappaB to bind to DNA or activate gene expression, and siRNA-mediated reduction of FBXL11 expression has the opposite effects. The H212A mutation of FBXL11 abolishes both its histone H3K36 demethylase activity and its ability to inhibit NFkappaB. Thus, we have used a powerful tool for mutagenesis of mammalian cells to reveal an aspect of the complex regulation of NFkappaB-dependent signaling.
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Superior pole sleeve fracture following patellar stabilisation.
Knee
PUBLISHED: 08-07-2009
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Sleeve fractures of the superior pole of the patella are rare. The importance of their diagnosis lies in the fact that the avulsed fragment contains a source of bone forming tissue which may lead to duplication or enlargement of the patella. We report a case in a 16 year old boy who underwent plication of the medial patellofemoral ligament, vastus medialis obliquus advancement and percutaneous lateral release, for recurrent instability. Interruption of the blood supply with subsequent avascular necrosis is one possible mechanism for this complication. Another more likely mechanism is that of failure of the repair and re-dislocation, which may have been contributed to by prolonged cast immobilization.
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Reduction in mortality and target-lesion revascularisation at 2 years: a comparison between drug-eluting stents and conventional bare-metal stents in the "real world".
Int. J. Cardiol.
PUBLISHED: 07-16-2009
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Long-term safety of drug-eluting stent (DES) is still a concern. We aimed to assess the impact of DES use on all-cause mortality and target-lesion revascularisation (TLR) in routine clinical practice.
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Production of microsclerotia of the fungal entomopathogen Metarhizium anisopliae and their potential for use as a biocontrol agent for soil-inhabiting insects.
Mycol. Res.
PUBLISHED: 03-05-2009
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Microsclerotia (MS), overwintering structures produced by many plant pathogenic fungi, have not been described for Metarhizium anisopliae. Three strains of M. anisopliae--F52, TM109, and MA1200--formed MS in shake flask cultures using media with varying carbon concentrations and carbon-to-nitrogen (C:N) ratios. Under the conditions of this study, all strains produced MS, compact hyphal aggregates that become pigmented with culture age, in addition to more typical blastospores and mycelia. While all strains formed desiccation tolerant MS, highest concentrations (2.7-2.9 x 10(8) L(-1) liquid medium) were produced in rich media with C:N ratios of 30:1 and 50:1 by strain F52. All three strains of M. anisopliae produced similar biomass concentrations when media and growth time were compared. Strain MA1200 produced higher concentrations of blastospores than the other two strains of M. anisopliae with highest blastospore concentrations (1.6 and 4.2 x 10(8) blastospores ml(-1) on days 4 and 8, respectively) in media with the highest carbon and nitrogen concentrations. Microsclerotial preparations of M. anisopliae containing diatomaceous earth survived air-drying (to <5 % moisture) with no significant loss in viability. Rehydration and incubation of air-dried MS granules on water agar plates resulted in hyphal germination and sporogenic germination to produce high concentrations of conidia. Bioassays using soil-incorporated, air-dried MS preparations resulted in significant infection and mortality in larvae of the sugar beet root maggot, Tetanops myopaeformis. This is the first report of the production of sclerotial bodies by M. anisopliae and provides a novel approach for the control of soil-dwelling insects with this entomopathogenic fungus.
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Evaluation of allele frequencies of inherited disease genes in subgroups of American Quarter Horses.
J. Am. Vet. Med. Assoc.
PUBLISHED: 01-06-2009
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To estimate allele frequencies of the hyperkalaemic periodic paralysis (HYPP), lethal white foal syndrome (LWFS), glycogen branching enzyme deficiency (GBED), hereditary equine regional dermal asthenia (HERDA), and type 1 polysaccharide storage myopathy (PSSM) genes in elite performance subgroups of American Quarter Horses (AQHs).
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The pursuit of happiness: The social and scientific origins of Hans Selyes natural philosophy of life.
Hist Human Sci
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In 1956, Hans Selye tentatively suggested that the scientific study of stress could help us to formulate a precise program of conduct and teach us the wisdom to live a rich and meaningful life. Nearly two decades later, Selye expanded this limited vision of social order into a full-blown philosophy of life. In Stress without Distress, first published in 1974, he proposed an ethical code of conduct designed to mitigate personal and social problems. Basing his arguments on contemporary understandings of the biological processes involved in stress reactions, Selye referred to this code as altruistic egotism. This article explores the origins and evolution of Selyes natural philosophy of life, analysing the links between his theories and adjacent intellectual developments in biology, psychosomatic and psychosocial medicine, cybernetics and socio-biology, and situating his work in the broader cultural framework of modern western societies.
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Green tea polyphenols induce p53-dependent and p53-independent apoptosis in prostate cancer cells through two distinct mechanisms.
PLoS ONE
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Inactivation of the tumor suppressor gene p53 is commonly observed in human prostate cancer and is associated with therapeutic resistance. We have previously demonstrated that green tea polyphenols (GTP) induce apoptosis in prostate cancer cells irrespective of p53 status. However, the molecular mechanisms underlying these observations remain elusive. Here we investigated the mechanisms of GTP-induced apoptosis in human prostate cancer LNCaP cells stably-transfected with short hairpin-RNA against p53 (LNCaPshp53) and control vector (LNCaPshV). GTP treatment induced p53 stabilization and activation of downstream targets p21/waf1 and Bax in a dose-dependent manner specifically in LNCaPshV cells. However, GTP-induced FAS upregulation through activation of c-jun-N-terminal kinase resulted in FADD phosphorylation, caspase-8 activation and truncation of BID, leading to apoptosis in both LNCaPshV and LNCaPshp53 cells. In parallel, treatment of cells with GTP resulted in inhibition of survival pathway, mediated by Akt deactivation and loss of BAD phosphorylation more prominently in LNCaPshp53 cells. These distinct routes of cell death converged to a common pathway, leading to loss of mitochondrial transmembrane potential, cytochrome c release and activation of terminal caspases, resulting in PARP-cleavage. GTP-induced apoptosis was attenuated with JNK inhibitor, SP600125 in both cell lines; whereas PI3K-Akt inhibitor, LY294002 resulted in increased cell death prominently in LNCaPshp53 cells, establishing the role of two distinct pathways of GTP-mediated apoptosis. Furthermore, GTP exposure resulted in inhibition of class I HDAC protein, accumulation of acetylated histone-H3 in total cellular chromatin, resulting in increased accessibility of transcription factors to bind with the promoter sequences of p21/waf1 and Bax, regardless of the p53 status of cells, consistent with effects elicited by an HDAC inhibitor, trichostatin A. These results demonstrate that GTP induces prostate cancer cell death by two distinct mechanisms regardless of p53 status, thus identifying specific well-defined molecular mechanisms that may be targeted by chemopreventive and/or therapeutic strategies.
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dNTP Supply Gene Expression Patterns after P53 Loss.
Cancers (Basel)
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Loss of the transcription factor p53 implies mRNA losses of target genes such as the p53R2 subunit of human ribonucleotide reductase (RNR). We hypothesized that other genes in the dNTP supply system would compensate for such p53R2 losses and looked for this in our own data and in data of the Gene Expression Omnibus (GEO). We found that the de novo dNTP supply system compensates for p53R2 losses with increases in RNR subunit R1, R2, or both. We also found compensatory increases in cytosolic deoxycytidine kinase (dCK) and thymidine kinase 1 (TK1) and in mitochondrial deoxyguanosine kinase (dGK), all of the salvage dNTP supply system; in contrast, the remaining mitochondrial salvage enzyme thymidine kinase 2 (TK2) decreased with p53 loss. Thus, TK2 may be more dedicated to meeting mitochondrial dNTP demands than dGK which may be more obligated to assist cytosolic dNTP supply in meeting nuclear DNA dNTP demands.
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Respiratory and olfactory cytotoxicity of inhaled 2,3-pentanedione in Sprague-Dawley rats.
Am. J. Pathol.
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Flavorings-related lung disease is a potentially disabling disease of food industry workers associated with exposure to the ?-diketone butter flavoring, diacetyl (2,3-butanedione). To investigate the hypothesis that another ?-diketone flavoring, 2,3-pentanedione, would cause airway damage, rats that inhaled air, 2,3-pentanedione (112, 241, 318, or 354 ppm), or diacetyl (240 ppm) for 6 hours were sacrificed the following day. Rats inhaling 2,3-pentanedione developed necrotizing rhinitis, tracheitis, and bronchitis comparable to diacetyl-induced injury. To investigate delayed toxicity, additional rats inhaled 318 (range, 317.9-318.9) ppm 2,3-pentanedione for 6 hours and were sacrificed 0 to 2, 12 to 14, or 18 to 20 hours after exposure. Respiratory epithelial injury in the upper nose involved both apoptosis and necrosis, which progressed through 12 to 14 hours after exposure. Olfactory neuroepithelial injury included loss of olfactory neurons that showed reduced expression of the 2,3-pentanedione-metabolizing enzyme, dicarbonyl/L-xylulose reductase, relative to sustentacular cells. Caspase 3 activation occasionally involved olfactory nerve bundles that synapse in the olfactory bulb (OB). An additional group of rats inhaling 270 ppm 2,3-pentanedione for 6 hours 41 minutes showed increased expression of IL-6 and nitric oxide synthase-2 and decreased expression of vascular endothelial growth factor A in the OB, striatum, hippocampus, and cerebellum using real-time PCR. Claudin-1 expression increased in the OB and striatum. We conclude that 2,3-pentanedione is a respiratory hazard that can also alter gene expression in the brain.
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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.