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Find video protocols related to scientific articles indexed in Pubmed.
Peptide and small molecule inhibitors of HECT-type ubiquitin ligases.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 11-12-2014
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The human genome encodes several hundred E3 ubiquitin ligases containing RING domains, and around 28 containing HECT domains. These enzymes catalyze the transfer of ubiquitin from E2 enzyme thioesters to a huge range of substrates and play crucial roles in many cellular functions. This makes them attractive potential therapeutic targets. However, they have proven difficult to inhibit: very few good inhibitors exist for RING domain ligases, and none have been described for HECT ligases. Here we show that bicyclic peptides isolated by phage display [Heinis C, Rutherford T, Freund S, Winter G (2009) Nat Chem Biol. 5(7):502-507] can target the E2 binding sites on the HECT domains of Smurf2, Nedd4, Mule/Huwe1, and WWP1, and thus act as specific inhibitors of these enzymes in vitro. By screening for displacement of one of these peptides from Smurf2, we were able to identify a small molecule, heclin (HECT ligase inhibitor), which inhibits several HECT ligases in tissue culture cells. In vitro, heclin does not block E2 binding but causes a conformational change that results in oxidation of the active site Cys. This demonstrates that HECT domains are potentially druggable and provides molecules that may be of experimental use. Heclin kills HEK293 cells growing in culture, consistent with an essential role for HECT ligase activity in mammalian cells.
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Angelman syndrome imprinting center encodes a transcriptional promoter.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 11-08-2014
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Clusters of imprinted genes are often controlled by an imprinting center that is necessary for allele-specific gene expression and to reprogram parent-of-origin information between generations. An imprinted domain at 15q11-q13 is responsible for both Angelman syndrome (AS) and Prader-Willi syndrome (PWS), two clinically distinct neurodevelopmental disorders. Angelman syndrome arises from the lack of maternal contribution from the locus, whereas Prader-Willi syndrome results from the absence of paternally expressed genes. In some rare cases of PWS and AS, small deletions may lead to incorrect parent-of-origin allele identity. DNA sequences common to these deletions define a bipartite imprinting center for the AS-PWS locus. The PWS-smallest region of deletion overlap (SRO) element of the imprinting center activates expression of genes from the paternal allele. The AS-SRO element generates maternal allele identity by epigenetically inactivating the PWS-SRO in oocytes so that paternal genes are silenced on the future maternal allele. Here we have investigated functional activities of the AS-SRO, the element necessary for maternal allele identity. We find that, in humans, the AS-SRO is an oocyte-specific promoter that generates transcripts that transit the PWS-SRO. Similar upstream promoters were detected in bovine oocytes. This result is consistent with a model in which imprinting centers become DNA methylated and acquire maternal allele identity in oocytes in response to transiting transcription.
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Acute Nonarteritic Anterior Ischemic Optic Neuropathy and Exposure to Phosphodiesterase Type 5 Inhibitors.
J Sex Med
PUBLISHED: 11-01-2014
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Nonarteritic anterior ischemic optic neuropathy (NAION), a rare visual disorder, has been reported in men using phosphodiesterase type 5 inhibitors (PDE5i) for erectile dysfunction.
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Gene regulatory interactions at lateral organ boundaries in maize.
Development
PUBLISHED: 10-30-2014
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Maize leaves have distinct tissues that serve specific purposes. The blade tilts back to photosynthesize and the sheath wraps around the stem to provide structural support and protect young leaves. At the junction between blade and sheath are the ligule and auricles, both of which are absent in the recessive liguleless1 (lg1) mutant. Using an antibody against LG1, we reveal LG1 accumulation at the site of ligule formation and in the axil of developing tassel branches. The dominant mutant Wavy auricle in blade1 (Wab1-R) produces ectopic auricle tissue in the blade and increases the domain of LG1 accumulation. We determined that wab1 encodes a TCP transcription factor by positional cloning and revertant analysis. Tassel branches are few and upright in the wab1 revertant tassel and have an increased branch angle in the dominant mutant. wab1 mRNA is expressed at the base of branches in the inflorescence and is necessary for LG1 expression. wab1 is not expressed in leaves, except in the dominant mutant. The domain of wab1 expression in the Wab1-R leaf closely mirrors the accumulation of LG1. Although wab1 is not needed to induce lg1 expression in the leaf, LG1 is needed to counteract the severe phenotype of the dominant Wab1-R mutant. The regulatory interaction of LG1 and WAB1 reveals a link between leaf shape and tassel architecture, and suggests the ligule is a boundary similar to that at the base of lateral organs.
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The Role of Parental Distress in Moderating the Influence of Child Neglect on Maladjustment.
J Child Fam Stud
PUBLISHED: 10-28-2014
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Despite pervasive evidence of the harmful impact of neglect on children's adjustment, individual differences in adaptation persist. This study examines parental distress as a contextual factor that may moderate the relation between neglect and child adjustment, while considering the specificity of the relation between neglect and internalizing versus externalizing problems. In a sample of 66 children (33 with a documented child protective services history of neglect prior to age six), neglect predicted internalizing, and to a lesser extent externalizing, problems as rated by teachers at age seven. Parental distress moderated the relation between neglect and internalizing, but not externalizing, problems. Specifically, higher levels of neglect predicted more internalizing problems only among children of distressed parents. These findings indicate that parent-level variables are important to consider in evaluating the consequences of neglect, and point to the importance of considering contextual factors when identifying those children most at risk following neglect.
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A New Experimental Model for Assessing Drug Efficacy against Trypanosoma cruzi Infection Based on Highly Sensitive In Vivo Imaging.
J Biomol Screen
PUBLISHED: 10-10-2014
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The protozoan Trypanosoma cruzi is the causative agent of Chagas disease, one of the world's major neglected infections. Although development of improved antiparasitic drugs is considered a priority, there have been no significant treatment advances in the past 40 years. Factors that have limited progress include an incomplete understanding of pathogenesis, tissue tropism, and disease progression. In addition, in vivo models, which allow parasite burdens to be tracked throughout the chronic stage of infection, have been lacking. To address these issues, we have developed a highly sensitive in vivo imaging system based on bioluminescent T. cruzi, which express a red-shifted luciferase that emits light in the tissue-penetrating orange-red region of the spectrum. The exquisite sensitivity of this noninvasive murine model has been exploited to monitor parasite burden in real time throughout the chronic stage, has allowed the identification of the gastrointestinal tract as the major niche of long-term infection, and has demonstrated that chagasic heart disease can develop in the absence of locally persistent parasites. Here, we review the parameters of the imaging system and describe how this experimental model can be incorporated into drug development programs as a valuable tool for assessing efficacy against both acute and chronic T. cruzi infections.
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Perceived Harm, Addictiveness, and Social Acceptability of Tobacco Products and Marijuana Among Young Adults: Marijuana, Hookah, and Electronic Cigarettes Win.
Subst Use Misuse
PUBLISHED: 10-01-2014
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Background: There has been an increase in non-daily smoking, alternative tobacco product and marijuana use among young adults in recent years. Objectives: This study examined perceptions of health risks, addictiveness, and social acceptability of cigarettes, cigar products, smokeless tobacco, hookah, electronic cigarettes, and marijuana among young adults and correlates of such perceptions. Methods: In Spring 2013, 10,000 students at two universities in the Southeastern United States were recruited to complete an online survey (2,002 respondents), assessing personal, parental, and peer use of each product; and perceptions of health risks, addictiveness, and social acceptability of each of these products. Results: Marijuana was the most commonly used product in the past month (19.2%), with hookah being the second most commonly used (16.4%). The least commonly used were smokeless tobacco products (2.6%) and electronic cigarettes (4.5%). There were high rates of concurrent product use, particularly among electronic cigarette users. The most positively perceived was marijuana, with hookah and electronic cigarettes being second. While tobacco use and related social factors, related positively, influenced perceptions of marijuana, marijuana use and related social factors were not associated with perceptions of any tobacco product. Conclusions/Importance: Marketing efforts to promote electronic cigarettes and hookah to be safe and socially acceptable seem to be effective, while policy changes seem to be altering perceptions of marijuana and related social norms. Research is needed to document the health risks and addictive nature of emerging tobacco products and marijuana and evaluate efforts to communicate such risks to youth.
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Surgical treatments for esophageal cancers.
Ann. N. Y. Acad. Sci.
PUBLISHED: 10-01-2014
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The following, from the 12th OESO World Conference: Cancers of the Esophagus, includes commentaries on the role of the nurse in preparation of esophageal resection (ER); the management of patients who develop high-grade dysplasia after having undergone Nissen fundoplication; the trajectory of care for the patient with esophageal cancer; the influence of the site of tumor in the choice of treatment; the best location for esophagogastrostomy; management of chylous leak after esophagectomy; the optimal approach to manage thoracic esophageal leak after esophagectomy; the choice for operational approach in surgery of cardioesophageal crossing; the advantages of robot esophagectomy; the place of open esophagectomy; the advantages of esophagectomy compared to definitive chemoradiotherapy; the pathologist report in the resected specimen; the best way to manage patients with unsuspected positive microscopic margin after ER; enhanced recovery after surgery for ER: expedited care protocols; and long-term quality of life in patients following esophagectomy.
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Efficacy and safety of aciclovir mucoadhesive buccal tablet in immunocompetent patients with labial herpes (LIP Trial): a double-blind, placebo-controlled, self-initiated trial.
J Drugs Dermatol
PUBLISHED: 07-10-2014
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Single-day, high-dose systemic antiviral drugs are effective in the treatment of labial herpes (herpes labialis [HL]). Aciclovir Lauriad® mucoadhesive buccal tablet (ABT) is an innovative drug delivery system providing high and prolonged exposure to aciclovir in the oral cavity, supporting its evaluation as a single low dose in HL.
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Development and applications of radioactive nanoparticles for imaging of biological systems.
Wiley Interdiscip Rev Nanomed Nanobiotechnol
PUBLISHED: 06-17-2014
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Radioactive nanoparticles possess the ability to carry high payloads of radionuclides for noninvasive imaging of regions of interest inside the body. In this way, they can be used for nuclear imaging of systems such as normal physiology and disease states. Various methods have been developed to label nanoparticles using both radiometals and radiohalogens, for single-photon emission computed tomography (SPECT) or positron emission tomography (PET) imaging in laboratory animals. The use of imaging to develop radioactive nanoparticles with long circulation times and minimal reticuloendothelial uptakes led to the design of nanoparticle constructs for imaging animal models of chronic illnesses, such as cancer and cardiovascular disease. Further improvements in targeting were made by modifying these constructs with vectors having high affinity and specificity for diseased tissue. In addition, constructs containing more than one type of imaging material afforded nanoparticles with multimodal properties, such as those designed for nuclear, magnetic resonance, and/or optical detection. Given the close relationship between diagnosis and therapy, theranostic nanoparticles have also been developed both to deliver radiotherapy and monitor response by imaging. In this article, we review the use of radionuclides to label nanoparticles for development and applications involving noninvasive detection of normal and abnormal biological functions. WIREs Nanomed Nanobiotechnol 2014, 6:628-640. doi: 10.1002/wnan.1292 For further resources related to this article, please visit the WIREs website.
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Development and preliminary evaluation of an internet-based healthy eating program: randomized controlled trial.
J. Med. Internet Res.
PUBLISHED: 05-14-2014
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The HealthValues Healthy Eating Programme is a standalone Internet-based intervention that employs a novel strategy for promoting behavior change (analyzing one's reasons for endorsing health values) alongside other psychological principles that have been shown to influence behavior. The program consists of phases targeting motivation (dietary feedback and advice, analyzing reasons for health values, thinking about health-related desires, and concerns), volition (implementation intentions with mental contrasting), and maintenance (reviewing tasks, weekly tips).
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Wnt-responsive cancer stem cells are located close to distorted blood vessels and not in hypoxic regions in a p53-null mouse model of human breast cancer.
Stem Cells Transl Med
PUBLISHED: 05-05-2014
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Cancer stem cells (CSCs, or tumor-initiating cells) may be responsible for tumor formation in many types of cancer, including breast cancer. Using high-resolution imaging techniques, we analyzed the relationship between a Wnt-responsive, CSC-enriched population and the tumor vasculature using p53-null mouse mammary tumors transduced with a lentiviral Wnt signaling reporter. Consistent with their localization in the normal mammary gland, Wnt-responsive cells in tumors were enriched in the basal/myoepithelial population and generally located in close proximity to blood vessels. The Wnt-responsive CSCs did not colocalize with the hypoxia-inducible factor 1?-positive cells in these p53-null basal-like tumors. Average vessel diameter and vessel tortuosity were increased in p53-null mouse tumors, as well as in a human tumor xenograft as compared with the normal mammary gland. The combined strategy of monitoring the fluorescently labeled CSCs and vasculature using high-resolution imaging techniques provides a unique opportunity to study the CSC and its surrounding vasculature.
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Development of peptide-based lineage-specific serology for chronic Chagas disease: geographical and clinical distribution of epitope recognition.
PLoS Negl Trop Dis
PUBLISHED: 05-01-2014
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Chagas disease, caused by infection with the protozoan Trypanosoma cruzi, remains a serious public health issue in Latin America. Genetically diverse, the species is sub-divided into six lineages, known as TcI-TcVI, which have disparate geographical and ecological distributions. TcII, TcV, and TcVI are associated with severe human disease in the Southern Cone countries, whereas TcI is associated with cardiomyopathy north of the Amazon. T. cruzi persists as a chronic infection, with cardiac and/or gastrointestinal symptoms developing years or decades after initial infection. Identifying an individual's history of T. cruzi lineage infection directly by genotyping of the parasite is complicated by the low parasitaemia and sequestration in the host tissues.
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Surgical clip migration following laparoscopic cholecystectomy as a cause of cholangitis.
J Surg Case Rep
PUBLISHED: 04-17-2014
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Gallstone disease is a common surgical presentation, and laparoscopic cholecystectomy is the favoured method of surgical management. Ligation of the cystic duct is usually performed with surgical clips, which have the potential to migrate into the common bile duct with time. This paper describes a case of cholangitis secondary to clip migration in a 42-year-old male patient 9 years after the initial laparoscopic cholecystectomy. Magnetic resonance cholangiopancreaography imaging revealed a surgical clip lodged in dilated common bile duct. The patient was managed successfully by endoscopic retrograde cholangiopancreatography.
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STAT3 signaling is activated preferentially in tumor-initiating cells in claudin-low models of human breast cancer.
Stem Cells
PUBLISHED: 04-16-2014
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In breast cancer, a subset of tumor-initiating cells (TIC) or "cancer stem cells" are thought to be responsible for tumor maintenance, treatment resistance, and disease recurrence. While current breast cancer stem cell markers (e.g., CD44(high) /CD24(low/neg) , ALDH positive) have allowed enrichment for such cells, they are not universally expressed and may actually identify distinct TIC subpopulations in the same tumor. Thus, additional markers of functional stem cells are needed. The STAT3 pathway is a critical regulator of the function of normal stem cells, and evidence is accumulating for its important role in breast cancer stem cells. However, due to the lack of a method for separating live cells based on their level of STAT3 activity, it remains unknown whether STAT3 functions in the cancer stem cells themselves, or in surrounding niche cells, or in both. To approach this question, we constructed a series of lentiviral fluorescent (enhanced green fluorescent protein, EGFP) reporters that enabled flow cytometric enrichment of cells differing in STAT3-mediated transcriptional activity, as well as in vivo/in situ localization of STAT3 responsive cells. Using in vivo claudin-low cell line xenograft models of human breast cancer, we found that STAT3 signaling reporter activity (EGFP(+) ) is associated with a subpopulation of cancer cells enriched for mammosphere-forming efficiency, as well as TIC function in limiting dilution transplantation assays compared to negative or unsorted populations. Our results support STAT3 signaling activity as another functional marker for human breast cancer stem cells thus making it an attractive therapeutic target for stem-cell-directed therapy in some breast cancer subtypes.
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Tobacco control environment in the United States and individual consumer characteristics in relation to continued smoking: differential responses among menthol smokers?
Prev Med
PUBLISHED: 04-15-2014
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We used a consumer panel augmented with state-specific measures of tobacco control activities to examine the main effects and interactions among consumer behaviors, particularly menthol cigarette smoking, and tobacco control environment on cessation over a six-year period.
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Twenty-four hour variation in heart rate variability indices derived from fractional differintegration.
Clin Physiol Funct Imaging
PUBLISHED: 03-27-2014
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Assuming that RR time-series behave as a fractionally differintegrated Gaussian process, García-González et al. (2003) recently proposed new indices for quantifying variability and structure in RR data. One of these was the 'fractional noise quantifier' (fnQ), measuring the departure of an RR time-series from a monofractal structure (i.e. a measure of its multifractality). Sixty-nine participants (aged = 34·5 ± 12·4 years, body mass index (BMI) = 23·9 ± 2·9 kg m(-2) , maximal oxygen uptake rate (V?O2peak ) = 42·4 ± 10·9 ml min(-1)  kg(-1) , 39 males) provided continuous beat-to-beat ECG recordings for a 24-h period. Fractional differintegration was used to quantify fnQ, and heart rate variability was calculated in the time domain. All variables were evaluated during consecutive 1-h periods and also during four 6-h blocks corresponding to morning, afternoon, evening and night periods. Apart from RR, circadian trends in all variables were independent of gender (P = 0·11-0·59). Apart from fnQ, all variables exhibited circadian variation (0·0005
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Multilocus sequence and microsatellite identification of intra-specific hybrids and ancestor-like donors among natural Ethiopian isolates of Leishmania donovani.
Int. J. Parasitol.
PUBLISHED: 03-07-2014
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Protozoan parasites of the genus Leishmania (Kinetoplastida: Trypanosomatidae) cause widespread and devastating human diseases. Visceral leishmaniasis is endemic in Ethiopia where it has also been responsible for fatal epidemics. It is postulated that genetic exchange in Leishmania has implications for heterosis (hybrid vigour), spread of virulent strains, resistance to chemotherapeutics, and exploitation of different hosts and vectors. Here we analyse 11 natural Ethiopian Leishmania donovani isolates consisting of four putative hybrids, seven parent-like isolates and over 90 derived biological clones. We apply a novel combination of high resolution multilocus microsatellite typing (five loci) and multilocus sequence typing (four loci) that together distinguish parent-like and hybrid L. donovani strains. Results indicate that the four isolates (and their associated biological clones) are genetic hybrids, not the results of mixed infections, each possessing heterozygous markers consistent with inheritance of divergent alleles from genetically distinct Ethiopian L. donovani lineages. The allelic profiles of the putative hybrids may have arisen from a single hybridisation event followed by inbreeding or gene conversion, or alternatively from two or more hybridisation events. Mitochondrial sequencing showed uniparental maxicircle inheritance for all of the hybrids, each possessing a single mitochondrial genotype. Fluorescence activated cell sorting analysis of DNA content demonstrated that all hybrids and their associated clones were diploid. Together the data imply that intra-specific genetic exchange is a recurrent feature of natural L. donovani populations, with substantial implications for the phyloepidemiology of Leishmania.
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Long-Term Outcomes and Recurrence Patterns in Upper Gastrointestinal Tract Gastrointestinal Stromal Tumours (GISTs) Treated by Minimally Invasive Surgery.
Dig Surg
PUBLISHED: 03-05-2014
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Gastrointestinal stromal tumours are the most frequently occurring sarcoma of the gastrointestinal tract. Current treatment involves complete resection although the surgical or pathological margin required remains unclear. In this study we aimed to examine the risk of local and distant recurrence following laparoscopic resection.
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Bioluminescence imaging of chronic Trypanosoma cruzi infections reveals tissue-specific parasite dynamics and heart disease in the absence of locally persistent infection.
Cell. Microbiol.
PUBLISHED: 02-19-2014
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Chronic Trypanosoma cruzi infections lead to cardiomyopathy in 20-30% of cases. A causal link between cardiac infection and pathology has been difficult to establish because of a lack of robust methods to detect scarce, focally distributed parasites within tissues. We developed a highly sensitive bioluminescence imaging system based on T. cruzi expressing a novel luciferase that emits tissue-penetrating orange-red light. This enabled long-term serial evaluation of parasite burdens in individual mice with an in vivo limit of detection of significantly less than 1000 parasites. Parasite distributions during chronic infections were highly focal and spatiotemporally dynamic, but did not localize to the heart. End-point ex vivo bioluminescence imaging allowed tissue-specific quantification of parasite loads with minimal sampling bias. During chronic infections, the gastro-intestinal tract, specifically the colon and stomach, was the only site where T. cruzi infection was consistently observed. Quantitative PCR-inferred parasite loads correlated with ex vivo bioluminescence and confirmed the gut as the parasite reservoir. Chronically infected mice developed myocarditis and cardiac fibrosis, despite the absence of locally persistent parasites. These data identify the gut as a permissive niche for long-term T. cruzi infection and show that canonical features of Chagas disease can occur without continual myocardium-specific infection.
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Membrane-localized estrogen receptor ? is required for normal organ development and function.
Dev. Cell
PUBLISHED: 02-18-2014
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Steroid receptors are found in discrete cellular locations, but it is unknown whether extranuclear pools are necessary for normal organ development. To assess this, we developed a point mutant estrogen receptor ? (ER?) knockin mouse (C451A) that precludes palmitoylation and membrane trafficking of the steroid receptor in all organs. Homozygous knockin female mice (nuclear-only ER? [NOER]) show loss of rapid signaling that occurs from membrane ER? in wild-type mice. Multiple developmental abnormalities were found, including infertility, relatively hypoplastic uteri, abnormal ovaries, stunted mammary gland ductal development, and abnormal pituitary hormone regulation in NOER mice. These abnormalities were rescued in heterozygous NOER mice that were comparable to wild-type mice. mRNAs implicated in organ development were often poorly stimulated by estrogen only in homozygous NOER mice. We conclude that many organs require membrane ER? and resulting signal transduction to collaborate with nuclear ER? for normal development and function.
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Diagnostic ultrasound features and outcome of restrictive foramen ovale in fetuses with structurally normal hearts.
Pediatr Cardiol
PUBLISHED: 02-04-2014
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Intrauterine foramen ovale (FO) restriction in association with congenital heart disease (CHD) carries a poor prognosis. However, in the absence of CHD, the clinical importance of restrictive FO in the fetus is not well understood. We evaluated the antenatal prevalence, clinical presentation, diagnostic ultrasound features, and outcome of restrictive FO in fetuses without CHD. We reviewed the echocardiographic and clinical records of 23 fetuses diagnosed with a restrictive FO and structurally normal heart between 2001 and 2012. The atrial septum, dimensions of cardiac structures, left and right cardiac output and Doppler interrogation of cardiac flows were examined. The clinical outcomes of all fetuses with restrictive FO were analysed. Restrictive FO was identified in 23 of 1,682 (1.4%) fetuses with no CHD. Enlarged right heart structures (100%), hypermobile or redundant primum atrial septum (91%), increased right-to-left ventricular cardiac output ratio (91%), and posteriorly angulated ductus arteriosus (68%) were the most common echocardiographic findings associated with this rare phenomenon. Additional noncardiac systemic abnormalities were identified in 13 (56%) babies. Seven (30%) neonates developed persistent pulmonary hypertension, and 7 infants died. Antenatal restrictive FO is an underrecognised entity despite being a common cause of right heart dilatation in the fetus. In the absence of CHD, restrictive FO is well tolerated antenatally, but its frequent association with noncardiac abnormalities and pulmonary hypertension in the neonate are noteworthy.
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Effect of seasonal variation on the composition and properties of raw milk destined for processing in the UK.
Food Chem
PUBLISHED: 02-03-2014
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The composition and physical properties of raw milk from a commercial herd were studied over a 1 year period in order to understand how best to utilise milk for processing throughout the year. Protein and fat levels demonstrated seasonal trends, while minerals and many physical properties displayed considerable variations, which were apparently unrelated to season. However, rennet clotting time, ethanol stability and foaming ability were subject to seasonal variation. Many significant interrelationships in physico-chemical properties were found. It is clear that the milk supply may be more suited to the manufacture of different products at different times of the year or even on a day to day basis. Subsequent studies will report on variation in production and quality of products manufactured from the same milk samples described in the current study and will thus highlight potential advantages of seasonal processing of raw milk.
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Type I collagen as an extracellular matrix for the in vitro growth of human small intestinal epithelium.
PLoS ONE
PUBLISHED: 01-01-2014
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We previously reported in vitro maintenance and proliferation of human small intestinal epithelium using Matrigel, a proprietary basement membrane product. There are concerns over the applicability of Matrigel-based methods for future human therapies. We investigated type I collagen as an alternative for the culture of human intestinal epithelial cells.
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Signal intensities derived from different NMR probes and parameters contribute to variations in quantification of metabolites.
PLoS ONE
PUBLISHED: 01-01-2014
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We discovered that serious issues could arise that may complicate interpretation of metabolomic data when identical samples are analyzed at more than one NMR facility, or using slightly different NMR parameters on the same instrument. This is important because cross-center validation metabolomics studies are essential for the reliable application of metabolomics to clinical biomarker discovery. To test the reproducibility of quantified metabolite data at multiple sites, technical replicates of urine samples were assayed by 1D-(1)H-NMR at the University of Alberta and the University of Michigan. Urine samples were obtained from healthy controls under a standard operating procedure for collection and processing. Subsequent analysis using standard statistical techniques revealed that quantitative data across sites can be achieved, but also that previously unrecognized NMR parameter differences can dramatically and widely perturb results. We present here a confirmed validation of NMR analysis at two sites, and report the range and magnitude that common NMR parameters involved in solvent suppression can have on quantitated metabolomics data. Specifically, saturation power levels greatly influenced peak height intensities in a frequency-dependent manner for a number of metabolites, which markedly impacted the quantification of metabolites. We also investigated other NMR parameters to determine their effects on further quantitative accuracy and precision. Collectively, these findings highlight the importance of and need for consistent use of NMR parameter settings within and across centers in order to generate reliable, reproducible quantified NMR metabolomics data.
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Intestinal subepithelial myofibroblasts support the growth of intestinal epithelial stem cells.
PLoS ONE
PUBLISHED: 01-01-2014
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Intestinal epithelial stem cells (ISCs) are the focus of recent intense study. Current in vitro models rely on supplementation with the Wnt agonist R-spondin1 to support robust growth, ISC self-renewal, and differentiation. Intestinal subepithelial myofibroblasts (ISEMFs) are important supportive cells within the ISC niche. We hypothesized that co-culture with ISEMF enhances the growth of ISCs in vitro and allows for their successful in vivo implantation and engraftment. ISC-containing small intestinal crypts, FACS-sorted single ISCs, and ISEMFs were procured from C57BL/6 mice. Crypts and single ISCs were grown in vitro into enteroids, in the presence or absence of ISEMFs. ISEMFs enhanced the growth of intestinal epithelium in vitro in a proximity-dependent fashion, with co-cultures giving rise to larger enteroids than monocultures. Co-culture of ISCs with supportive ISEMFs relinquished the requirement of exogenous R-spondin1 to sustain long-term growth and differentiation of ISCs. Mono- and co-cultures were implanted subcutaneously in syngeneic mice. Co-culture with ISEMFs proved necessary for successful in vivo engraftment and proliferation of enteroids; implants without ISEMFs did not survive. ISEMF whole transcriptome sequencing and qPCR demonstrated high expression of specific R-spondins, well-described Wnt agonists that supports ISC growth. Specific non-supportive ISEMF populations had reduced expression of R-spondins. The addition of ISEMFs in intestinal epithelial culture therefore recapitulates a critical element of the intestinal stem cell niche and allows for its experimental interrogation and biodesign-driven manipulation.
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Influence of somatic state on cardiovascular measurements in pregnancy.
Physiol Meas
PUBLISHED: 12-17-2013
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Normal pregnancy causes marked changes in cardiac and haemodynamic function but there is continuing debate about the patterns of normal change. We believe that this lack of consensus is in large part caused by inappropriate assessment conditions. This study aimed to assess physiological data obtained from pregnant women during multiple steady-states and during between-state changes. The study was a longitudinal characterization of apparently healthy pregnant women aged >18 years with assessments at three antenatal stages (12-16, 26-28 and 34-36 weeks) and at 12 weeks following birth. Cardiovascular and heart rate variability (HRV) measures were quantified non-invasively during a range of states including postural manoeuvre, exercise and respiratory regulation. Cardiovascular and HRV variables were influenced by pregnancy in specific ways: (1) steady-state values were influenced differently to state-change responses; (2) cardiac output (CO) increased progressively throughout pregnancy in all states except supine rest; (3) the ?CO response to the supine-standing manoeuvre was particularly sensitive to pregnancy stage; (4) blood pressure was unaffected by pregnancy; (6) ?CO and ?SBP (systolic blood pressure) were enhanced from mid-pregnancy onwards; (7) ?HRV responses to state changes were markedly and progressively influenced by pregnancy. This study indicates that cardiovascular function in pregnant women is best quantified during at least one physical state change (in particular during the supine-to-standing manoeuvre) and that assessment during supine rest is inadequate for quantifying antenatal physiological function.
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Regulatory modules controlling maize inflorescence architecture.
Genome Res.
PUBLISHED: 12-04-2013
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Genetic control of branching is a primary determinant of yield, regulating seed number and harvesting ability, yet little is known about the molecular networks that shape grain-bearing inflorescences of cereal crops. Here, we used the maize (Zea mays) inflorescence to investigate gene networks that modulate determinacy, specifically the decision to allow branch growth. We characterized developmental transitions by associating spatiotemporal expression profiles with morphological changes resulting from genetic perturbations that disrupt steps in a pathway controlling branching. Developmental dynamics of genes targeted in vivo by the transcription factor RAMOSA1, a key regulator of determinacy, revealed potential mechanisms for repressing branches in distinct stem cell populations, including interactions with KNOTTED1, a master regulator of stem cell maintenance. Our results uncover discrete developmental modules that function in determining grass-specific morphology and provide a basis for targeted crop improvement and translation to other cereal crops with comparable inflorescence architectures.
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Statin Use is Associated With Reduced Risk of Histologic Subtypes of Esophageal Cancer: a Nested Case-Control Analysis.
Gastroenterology
PUBLISHED: 11-21-2013
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Most patients with esophageal adenocarcinoma (EAC) or squamous cell cancer (ESCC) present with advanced, incurable disease. Statins have reported anti-carcinogenic effects and may be chemoprotective. We investigated the association between regular use of statins and the main histologic subtypes of esophageal malignancy (EAC, esophagogastric junctional adenocarcinoma [EGJA], and ESCC) in the UK general population.
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Attitudes toward Web application supporting pharmacist-clinician comanagement of postexposure prophylaxis patients.
J Am Pharm Assoc (2003)
PUBLISHED: 11-05-2013
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To qualitatively explore clinician and pharmacist attitudes toward using a Web application virtual pharmacist-clinician partnership (VPCP) to assist with comanaged care of illicit drug-using patients prescribed postexposure prophylaxis (PEP).
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Highly Sensitive In Vivo Imaging of Trypanosoma brucei Expressing "Red-Shifted" Luciferase.
PLoS Negl Trop Dis
PUBLISHED: 11-01-2013
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Human African trypanosomiasis is caused by infection with parasites of the Trypanosoma brucei species complex, and threatens over 70 million people in sub-Saharan Africa. Development of new drugs is hampered by the limitations of current rodent models, particularly for stage II infections, which occur once parasites have accessed the CNS. Bioluminescence imaging of pathogens expressing firefly luciferase (emission maximum 562 nm) has been adopted in a number of in vivo models of disease to monitor dissemination, drug-treatment and the role of immune responses. However, lack of sensitivity in detecting deep tissue bioluminescence at wavelengths below 600 nm has restricted the wide-spread use of in vivo imaging to investigate infections with T. brucei and other trypanosomatids.
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The pathological features of surgically managed adrenal cysts: a 15-year retrospective review.
Am Surg
PUBLISHED: 10-30-2013
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Adrenal cysts are rare. Most are benign but some may contain malignancy. There are no established guidelines for their surgical management. The purpose of this study was to determine the pathological findings and likelihood of malignancy in hormonally inactive adrenal cysts after adrenalectomy. Using the pathology registries at two centers, we identified patients who underwent excision of an adrenal cyst between 1994 and 2009. Hormonally active cysts including pheochromocytomas were excluded. Charts were reviewed for patient demographics, presentation, surgical management, and postoperative course. Of 551 adrenalectomy specimens, 15 (2.7%) contained an inactive adrenal cyst or cystic component. Cysts were more likely to be in women (67%) and right-sided (73%). Three patients (20%) were symptomatic from their lesion. Laparoscopic adrenalectomy was performed in nine patients (60%). Pathology revealed eight hemorrhagic cysts, four lymphangiomas, one hemangioma, one epithelial cyst, and one metastatic pulmonary adenocarcinoma. Laboratory and radiographic workup are essential in determining whether adrenal cysts have hormonal function or a solid tissue component before adrenalectomy. Although nonfunctional adrenal cysts may contain malignancy, most are benign. It is reasonable to observe asymptomatic, nonfunctioning, benign-appearing adrenal cysts in patients in whom follow-up can be ensured.
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Small molecule inhibitors of zinc-dependent histone deacetylases.
Neurotherapeutics
PUBLISHED: 10-09-2013
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Lysine acetylation is an ancient, evolutionarily conserved, reversible post-translational modification. A multitude of diverse cellular functions are regulated by this dynamic modification, including energy and metabolism, protein folding, transcription, and translation. Gene expression can be manipulated through changes in histone acetylation status, and this process is controlled by the function of 2 opposing enzymes: histone acetyl transferases and histone deacetylases (HDACs). The zinc-dependent HDACs are a family of hydrolases that remove acetyl groups from lysines, and their function can be modulated by the action of small molecule ligands. Inhibition through competitive binding of the catalytic domain of these enzymes has been achieved by a diverse array of small molecule chemotypes. Structural biology has aided the development of potent, and in some cases highly isoform-selective, inhibitors that have demonstrated utility in a number of neurological disease models. Continued development and characterization of highly optimized small molecule inhibitors of HDAC enzymes will help refine our understanding of their function and, optimistically, lead to novel therapeutic treatment alternatives for a host of neurological disorders.
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Therapeutic potential of isoform selective HDAC inhibitors for the treatment of schizophrenia.
Future Med Chem
PUBLISHED: 09-13-2013
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Increasing evidence supports a role for epigenetic involvement in some of the neurobiological alterations observed in neurodegenerative and psychiatric disorders including schizophrenia. In particular, there is mounting evidence implicating dysfunction in acetylation status, a chromatin modification mediated in part by HDACs, as a possible contributing factor to certain facets of this debilitating disease. Additional data support the notion that small molecule inhibition of HDACs may provide therapeutic alternatives to treating many of the symptoms associated with schizophrenia, particularly cognitive deficits. However, the development of highly potent and selective inhibitors of the individual HDAC isoforms will be necessary to delineate the associated biological effects and test the feasibility of such an approach for this complex and chronically treated disease. Here, we summarize current evidence for the role of HDAC isoforms in schizophrenia and highlight the state of the art in developing selective inhibitors of these isoforms as a potential treatment for schizophrenia.
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New onset pancytopenia in adults: a review of underlying pathologies and their associated clinical and laboratory findings.
Leuk. Lymphoma
PUBLISHED: 08-20-2013
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Pancytopenia is regularly encountered in hematology practice, yet there exist few published assessments of the frequencies of various etiologies, and these frequencies exhibit substantial geographic variation. We reviewed bone marrow specimens from pancytopenic adults to determine the most common etiologies and to identify associations with clinical and laboratory findings. Of 132 patients with no history of hematolymphoid neoplasia, no prior bone marrow study for pancytopenia and no recent cytotoxic chemotherapy, 64% had clonal hematopoietic disorders. Most common were myeloid processes: 26% of patients had acute myeloid leukemia, and 17% had myelodysplasia. Less common were lymphoid neoplasms such as non-Hodgkin lymphoma (6%), hairy cell leukemia (5%) and precursor B acute lymphoblastic leukemia (4%). Among non-clonal cases, the most common specific diagnoses were aplastic anemia (5%), megaloblastic anemia (2%) and human immunodeficiency virus (HIV)-related changes (2%). Clonal diagnoses were associated with more severe cytopenias than non-clonal cases. Circulating nucleated erythroid precursors, immature granulocytes and blasts were seen more frequently in clonal cases. Nearly two-thirds of cases of new onset pancytopenia in adults in our North American practice setting have a clonal etiology, with myeloid neoplasms being most common. Blood counts and peripheral smear findings can provide insights into the likelihood of a clonal etiology.
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Prenatal tobacco exposure predicts differential brain function during working memory in early adolescence: a preliminary investigation.
Brain Imaging Behav
PUBLISHED: 08-13-2013
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Children prenatally exposed to tobacco exhibit higher rates of learning and emotional-behavioral problems related to worse working memory performance. Brain function, however, among tobacco exposed children while performing a working memory task has not previously been examined. This study compared the brain function of tobacco-exposed (n?=?7) and unexposed (n?=?11) 12-year-olds during a number N-back working memory task using an event-related functional magnetic resonance imaging (fMRI) design. Prenatal alcohol exposure, neonatal medical problems, environmental risk, and sex were statistically controlled. Tobacco-exposed children showed greater activation in inferior parietal regions, whereas unexposed children showed greater activation in inferior frontal regions. These differences were observed in the context of correct responses, suggesting that exposed and unexposed children use different brain regions and approaches to succeed in working memory tasks. Implications for future research and intervention are discussed.
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Acute ischemic complications of PCI and CABG: who should cover whom for coronary revascularization?
J Interv Cardiol
PUBLISHED: 07-16-2013
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Percutaneous coronary intervention (PCI) has historically required cardiothoracic backup in the event of ischemic complications. However, many complications occurring during PCI can now be effectively treated at the time of the indexed procedure. Equally, ischemic complications, which occur following coronary artery bypass grafting (CABG), which were previously treated medically or with reoperation, may now also be effectively treated by acute PCI.
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Cancer stem cell markers are enriched in normal tissue adjacent to triple negative breast cancer and inversely correlated with DNA repair deficiency.
Breast Cancer Res.
PUBLISHED: 07-10-2013
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We hypothesized that cells present in normal tissue that bear cancer stem cell markers may represent a cancer cell of origin or a microenvironment primed for tumor development, and that their presence may correlate with the clinically defined subtypes of breast cancer that show increased tumorigenicity and stem cell features.
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Near-peer teaching in clinical neuroanatomy.
Clin Teach
PUBLISHED: 07-10-2013
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Near-peer teaching involves students being taught by more senior students and draws on their similar knowledge base and shared experiences. It has been used previously for teaching gross anatomy, but has not yet been reported specifically for neuroanatomy. At the University of Southampton there is no formal neuroanatomy teaching during the clinical years, and so a near-peer teaching programme was developed to support students, learning in between attending their clinical attachments.
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Canonical Wnt signals combined with suppressed TGF?/BMP pathways promote renewal of the native human colonic epithelium.
Gut
PUBLISHED: 07-05-2013
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A defining characteristic of the human intestinal epithelium is that it is the most rapidly renewing tissue in the body. However, the processes underlying tissue renewal and the mechanisms that govern their coordination have proved difficult to study in the human gut.
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Molecular epidemiologic source tracking of orally transmitted Chagas disease, Venezuela.
Emerging Infect. Dis.
PUBLISHED: 06-18-2013
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Oral outbreaks of Chagas disease are increasingly reported in Latin America. The transitory presence of Trypanosoma cruzi parasites within contaminated foods, and the rapid consumption of those foods, precludes precise identification of outbreak origin. We report source attribution for 2 peri-urban oral outbreaks of Chagas disease in Venezuela via high resolution microsatellite typing.
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Scrub typhus with sepsis and acute respiratory distress syndrome.
J. Clin. Microbiol.
PUBLISHED: 06-12-2013
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Scrub typhus is a major infectious threat in the Asia-Pacific region. We report an unusual case of scrub typhus in a patient in Singapore who presented with sepsis and acute respiratory distress syndrome but lacked the pathognomonic eschar. The patient recovered after appropriate diagnosis and doxycycline treatment. Rickettsial diseases should be included in the differential diagnosis of febrile illnesses in regions where the diseases are endemic, and absence of eschar should not be the criterion used to rule out scrub typhus.
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Antimicrobial resistance and virulence traits of Enterococcus faecalis from primary endodontic infections.
J Dent
PUBLISHED: 05-10-2013
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To determine the phenotypic and molecular characteristics of Enterococcus faecalis recovered from primary endodontic infections in Brazilian patients.
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Use of collagen gel as an alternative extracellular matrix for the in vitro and in vivo growth of murine small intestinal epithelium.
Tissue Eng Part C Methods
PUBLISHED: 05-10-2013
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Methods for the in vitro culture of primary small intestinal epithelium have improved greatly in recent years. A critical barrier for the translation of this methodology to the patients bedside is the ability to grow intestinal stem cells using a well-defined extracellular matrix. Current methods rely on the use of Matrigel(™), a proprietary basement membrane-enriched extracellular matrix gel produced in mice that is not approved for clinical use. We demonstrate for the first time the capacity to support the long-term in vitro growth of murine intestinal epithelium in monoculture, using type I collagen. We further demonstrate successful in vivo engraftment of enteroids co-cultured with intestinal subepithelial myofibroblasts in collagen gel. Small intestinal crypts were isolated from 6 to 10 week old transgenic enhanced green fluorescent protein (eGFP+) mice and suspended within either Matrigel or collagen gel; cultures were supported using previously reported media and growth factors. After 1 week, cultures were either lysed for DNA or RNA extraction or were implanted subcutaneously in syngeneic host mice. Quantitative real-time polymerase chain reaction (qPCR) was performed to determine expansion of the transgenic eGFP-DNA and to determine the mRNA gene expression profile. Immunohistochemistry was performed on in vitro cultures and recovered in vivo explants. Small intestinal crypts reliably expanded to form enteroids in either Matrigel or collagen in both mono- and co-cultures as confirmed by microscopy and eGFP-DNA qPCR quantification. Collagen-based cultures yielded a distinct morphology with smooth enteroids and epithelial monolayer growth at the gel surface; both enteroid and monolayer cells demonstrated reactivity to Cdx2, E-cadherin, CD10, Periodic Acid-Schiff, and lysozyme. Collagen-based enteroids were successfully subcultured in vitro, whereas pure monolayer epithelial sheets did not survive passaging. Reverse transcriptase-polymerase chain reaction demonstrated evidence of Cdx2, villin 1, mucin 2, chromogranin A, lysozyme 1, and Lgr5 expression, suggesting a fully elaborated intestinal epithelium. Additionally, collagen-based enteroids co-cultured with myofibroblasts were successfully recovered after 5 weeks of in vivo implantation, with a preserved immunophenotype. These results indicate that collagen-based techniques have the capacity to eliminate the need for Matrigel in intestinal stem cell culture. This is a critical step towards producing neo-mucosa using good manufacturing practices for clinical applications in the future.
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Comparative biodistributions and dosimetry of [(177)Lu]DOTA-anti-bcl-2-PNA-Tyr(3)-octreotate and [(177)Lu]DOTA-Tyr(3)-octreotate in a mouse model of B-cell lymphoma/leukemia.
Nucl. Med. Biol.
PUBLISHED: 05-09-2013
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The B-cell lymphoma/leukemia-2 (bcl-2) proto-oncogene in non-Hodgkins lymphoma (NHL) is a dominant inhibitor of apoptosis. We developed a (177)Lu-labeled bcl-2 antisense peptide nucleic acid (PNA)-peptide conjugate designed for dual modality NHL therapy, consisting of a radiopharmaceutical capable of simultaneously down-regulating apoptotic resistance and delivering cytotoxic internally emitted radiation.
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Zebularine significantly sensitises MEC1 cells to external irradiation and radiopharmaceutical therapy when administered sequentially in vitro.
Cell Biol. Int.
PUBLISHED: 05-02-2013
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Zebularine is a cytidine analogue incorporated into DNA during replication, inhibiting DNA methyltransferase 1 (DNMT1), resulting in demethylation and changes in gene expression. Such modification may improve radiosensitivity in resistant lymphoma cells. The hypothesis of this study was that zebularine and radiation would synergistically inhibit cell growth and viability. Human MEC1 malignant B cells were incubated with 0-200?µM zebularine for 48?h. Media containing zebularine was removed, and the cells were irradiated with 0-2?Gy of either external beam irradiation or (177) Lu-DOTA-TATE, a radiolabelled somatostatin analogue. Concentration and viability were measured over 48-72?h. The proportion of apoptotic cells was identified using an active Caspase 3/7 assay. Zebularine inhibited growth of cells in a dose-dependent manner during exposure. No residual growth inhibition occurred following removal of the drug. Zebularine and external irradiation inhibited cell proliferation in a dose-dependent, synergistic interaction, but the effect on viability was additive. Treatment with zebularine and (177) Lu-DOTA-TATE resulted in less inhibition of proliferation (P?=?0.0135), but a synergistic decrease in viability. Apoptotic fraction was much higher in cells irradiated with (177) Lu-DOTA-TATE than external irradiation. External irradiation induces growth arrest rather than apoptosis. Apoptosis is the primary effect of radiopharmaceutical therapy on tumour cells. Treatment with the methylation inhibitor, zebularine, appears to synergistically augment these natural effects in vitro, which could be exploited clinically.
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Toxicities of oils, dispersants and dispersed oils to algae and aquatic plants: review and database value to resource sustainability.
Environ. Pollut.
PUBLISHED: 04-23-2013
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Phytotoxicity results are reviewed for oils, dispersants and dispersed oils. The phytotoxicity database consists largely of results from a patchwork of reactive research conducted after oil spills to marine waters. Toxicity information is available for at least 41 crude oils and 56 dispersants. As many as 107 response parameters have been monitored for 85 species of unicellular and multicellular algae, 28 wetland plants, 13 mangroves and 9 seagrasses. Effect concentrations have varied by as much as six orders of magnitude due to experimental diversity. This diversity restricts phytotoxicity predictions and identification of sensitive species, life stages and response parameters. As a result, evidence-based risk assessments for most aquatic plants and petrochemicals and dispersants are not supported by the current toxicity database. A proactive and experimentally-consistent approach is recommended to provide threshold toxic effect concentrations for sensitive life stages of aquatic plants inhabiting diverse ecosystems.
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Effects of the aromatic substitution pattern in cation-? sandwich complexes.
J Phys Chem A
PUBLISHED: 03-19-2013
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A computational study investigating the effects of the aromatic substitution pattern on the structure and binding energies of cation-? sandwich complexes is reported. The correlation between the binding energies (Ebind) and Hammett substituent constants is approximately the same as what is observed for cation-? half-sandwich complexes. For cation-? sandwich complexes where both aromatics contain substituents the issue of relative conformation is a possible factor in the strength of the binding; however, the work presented here shows the Ebind values are approximately the same regardless of the relative conformation of the two substituted aromatics. Finally, recent computational work has shown conflicting results on whether cation-? sandwich Ebind values (Ebind,S) are approximately equal to twice the respective half-sandwich Ebind values (Ebind,HS), or if cation-? sandwich Ebind,S values are less than double the respective half-sandwich Ebind,HS values. The work presented here shows that for cation-? sandwich complexes involving substituted aromatics the Ebind,S values are less than twice the respective half-sandwich Ebind,HS values, and this is termed nonadditive. The extent to which the cation-? sandwich complexes investigated here are nonadditive is greater for B3LYP calculated values than for MP2 calculated values and for sandwich complexes with electron-donating substituents than those with electron-withdrawing groups.
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CRK SH3N Domain Diminishes Cell Invasiveness of Non-Small Cell Lung Cancer.
Genes Cancer
PUBLISHED: 03-07-2013
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CRK (c-Crk) as an adaptor protein is involved in several oncogenic signal transduction pathways, conveying oncogenic signals to its downstream effectors and thereby affecting multiple cellular processes including proliferation, differentiation, and migration. For example, we have observed that CRK expression and phosphorylation influence the invasiveness of non-small cell lung cancer (NSCLC) cells. To intervene in CRK signaling pathway, we examined whether CRK protein domains can be used as therapeutic tools to interrupt CRK signaling, thus influencing the biological behavior of NSCLC cells. For this purpose, Src Homology domains of CRK-I (i.e., SH2 and SH3N domains) were overexpressed in H157, Rh2, and A549 cells. CRK-SH3N domain expression induced epithelial morphology in H157 cells and enhanced epithelial morphology of A549 and Rh2 cells as compared to cells transfected with CRK-SH2 domain or empty vector. In addition, CRK-SH3N domain expression significantly decreased the motility and invasiveness of A549 and H157 cells. Furthermore, CRK-SH3N domain expression disrupted the interaction of CRK-II with DOCK180. In summary, these data provide evidence that the CRK-SH3N domain can be used to influence the malignant phenotype of NSCLC cells and also reduce the metastatic potential of these cells.
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Adolescent risk-taking as a function of prenatal cocaine exposure and biological sex.
Neurotoxicol Teratol
PUBLISHED: 02-18-2013
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To examine the effects of prenatal cocaine exposure and biological sex on adolescent risk-taking while controlling for early environmental risk.
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Role of bacterial lipopolysaccharide in enhancing host immune response to Candida albicans.
Clin. Dev. Immunol.
PUBLISHED: 01-21-2013
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Human infections involving yeast of the genus Candida often occur in the presence of bacteria, and, as such, it is important to understand how these bacteria influence innate host immunity towards Candida. Dectin-1 is a cell receptor of macrophages for Candida albicans recognition. The aim of this study was to examine dectin-1 expression by monocytes after stimulation with bacterial lipopolysaccharide (LPS), followed by heat-killed C. albicans (HKC). Freshly isolated human peripheral blood monocytes (PBMCs) and human monocytes cell line (THP-1) cells expressed low levels of dectin-1. Stimulation with LPS and GM-CSF/IL-4 was found to increase dectin-1 expression in both CD14(+) human PBMC and THP-1 cells. Enhanced dectin-1 expression resulted in increased phagocytosis of Candida. When THP-1 cells were challenged only with HKC, detectable levels of IL-23 were not evident. However, challenge by LPS followed by varying concentrations of HKC resulted in increased IL-23 expression by THP-1 cells in HKC dose-dependent manner. Increased expression of IL-17 by PBMC also occurred after stimulation with Candida and LPS. In conclusion, bacterial LPS induces an enhanced immune response to Candida by immune cells, and this occurs through increasing dectin-1 expression.
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Low vitamin D status and suicide: a case-control study of active duty military service members.
PLoS ONE
PUBLISHED: 01-04-2013
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Considering that epidemiological studies show that suicide rates in many countries are highest in the spring when vitamin D status is lowest, and that low vitamin D status can affect brain function, we sought to evaluate if a low level of 25-hydroxyvitamin D [25(OH)D] could be a predisposing factor for suicide.
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Fish oil replacement in current aquaculture feed: is cholesterol a hidden treasure for fish nutrition?
PLoS ONE
PUBLISHED: 01-01-2013
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Teleost fish, as with all vertebrates, are capable of synthesizing cholesterol and as such have no dietary requirement for it. Thus, limited research has addressed the potential effects of dietary cholesterol in fish, even if fish meal and fish oil are increasingly replaced by vegetable alternatives in modern aquafeeds, resulting in progressively reduced dietary cholesterol content. The objective of this study was to determine if dietary cholesterol fortification in a vegetable oil-based diet can manifest any effects on growth and feed utilization performance in the salmonid fish, the rainbow trout. In addition, given a series of studies in mammals have shown that dietary cholesterol can directly affect the fatty acid metabolism, the apparent in vivo fatty acid metabolism of fish fed the experimental diets was assessed. Triplicate groups of juvenile fish were fed one of two identical vegetable oil-based diets, with additional cholesterol fortification (high cholesterol; H-Chol) or without (low cholesterol; L-Chol), for 12 weeks. No effects were observed on growth and feed efficiency, however, in fish fed H-Col no biosynthesis of cholesterol, and a remarkably decreased apparent in vivo fatty acid ?-oxidation were recorded, whilst in L-Chol fed fish, cholesterol was abundantly biosynthesised and an increased apparent in vivo fatty acid ?-oxidation was observed. Only minor effects were observed on the activity of stearyl-CoA desaturase, but a significant increase was observed for both the transcription rate in liver and the apparent in vivo activity of the fatty acid ?-6 desaturase and elongase, with increasing dietary cholesterol. This study showed that the possible effects of reduced dietary cholesterol in current aquafeeds can be significant and warrant future investigations.
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Interactions of Candida albicans with host epithelial surfaces.
J Oral Microbiol
PUBLISHED: 01-01-2013
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Candida albicans is an opportunistic, fungal pathogen of humans that frequently causes superficial infections of oral and vaginal mucosal surfaces of debilitated and susceptible individuals. The organism is however, commonly encountered as a commensal in healthy individuals where it is a component of the normal microflora. The key determinant in the type of relationship that Candida has with its host is how it interacts with the epithelial surface it colonises. A delicate balance clearly exists between the potentially damaging effects of Candida virulence factors and the nature of the immune response elicited by the host. Frequently, it is changes in host factors that lead to Candida seemingly changing from a commensal to pathogenic existence. However, given the often reported heterogeneity in morphological and biochemical factors that exist between Candida species and indeed strains of C. albicans, it may also be the fact that colonising strains differ in the way they exploit resources to allow persistence at mucosal surfaces and as a consequence this too may affect the way Candida interacts with epithelial cells. The aim of this review is to provide an overview of some of the possible interactions that may occur between C. albicans and host epithelial surfaces that may in turn dictate whether Candida removal, its commensal persistence or infection follows.
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A selective HDAC 1/2 inhibitor modulates chromatin and gene expression in brain and alters mouse behavior in two mood-related tests.
PLoS ONE
PUBLISHED: 01-01-2013
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Psychiatric diseases, including schizophrenia, bipolar disorder and major depression, are projected to lead global disease burden within the next decade. Pharmacotherapy, the primary--albeit often ineffective--treatment method, has remained largely unchanged over the past 50 years, highlighting the need for novel target discovery and improved mechanism-based treatments. Here, we examined in wild type mice the impact of chronic, systemic treatment with Compound 60 (Cpd-60), a slow-binding, benzamide-based inhibitor of the class I histone deacetylase (HDAC) family members, HDAC1 and HDAC2, in mood-related behavioral assays responsive to clinically effective drugs. Cpd-60 treatment for one week was associated with attenuated locomotor activity following acute amphetamine challenge. Further, treated mice demonstrated decreased immobility in the forced swim test. These changes are consistent with established effects of clinical mood stabilizers and antidepressants, respectively. Whole-genome expression profiling of specific brain regions (prefrontal cortex, nucleus accumbens, hippocampus) from mice treated with Cpd-60 identified gene expression changes, including a small subset of transcripts that significantly overlapped those previously reported in lithium-treated mice. HDAC inhibition in brain was confirmed by increased histone acetylation both globally and, using chromatin immunoprecipitation, at the promoter regions of upregulated transcripts, a finding consistent with in vivo engagement of HDAC targets. In contrast, treatment with suberoylanilide hydroxamic acid (SAHA), a non-selective fast-binding, hydroxamic acid HDAC 1/2/3/6 inhibitor, was sufficient to increase histone acetylation in brain, but did not alter mood-related behaviors and had dissimilar transcriptional regulatory effects compared to Cpd-60. These results provide evidence that selective inhibition of HDAC1 and HDAC2 in brain may provide an epigenetic-based target for developing improved treatments for mood disorders and other brain disorders with altered chromatin-mediated neuroplasticity.
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Lipopolysaccharide-induced M2 to M1 macrophage transformation for IL-12p70 production is blocked by Candida albicans mediated up-regulation of EBI3 expression.
PLoS ONE
PUBLISHED: 01-01-2013
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Macrophages are heterogeneous cell populations that are present in all tissues. Macrophages can be divided into classically activated inflammatory macrophages (M1) and alternatively activated anti-inflammatory macrophages (M2). It has been generally accepted that M1 macrophages are polarised in an inflammatory environment to produce pro-inflammatory cytokines, whilst M2 macrophages are involved in anti-inflammation and aid tissue repair in wound healing. Bacterial endotoxin (lipopolysaccharide; LPS) is a potent factor in infection, which induces M1 macrophages resulting in higher levels of iNOS, TNF? and IL-12p70 which dictate inflammatory T cell responses. M2 macrophages can be transformed into M1 macrophages following LPS stimulation to promote inflammation. Candida albicans is a commensal fungal microorganism, which has been suggested to induce immune tolerance; however, the mechanism of C. albicans-induced immune tolerance has not been investigated in detail. IL-35 is a recently identified anti-inflammatory cytokine which is a heterodimeric protein consisting of the Epstein-Barr virus-induced gene 3 (EBI3) and IL-12p35. IL-35 shares the protein subunit p35, with IL-12p70. IL-12p70 is the most potent cytokine to induce Th1 responses during inflammation. In this study, we demonstrate that heat-killed C. albicans (HKC) strongly suppressed LPS-induced IL-12p70 production in M2 macrophages. Candida albicans induced a high level of EBI3 expression in M2 macrophages, which served as a mechanism for IL-12p70 suppression by competitive binding of the common protein subunit (p35) of IL-35 and IL-12p70. To demonstrate that EBI3 expression had the ability to block IL-12p70 production intracellularly, a Chinese Hamster Ovary (CHO) cell line with biscistronic expression of IL-12p40 and p35 was constructed, followed by ectopic over-expression of EBI3. The over-expression of EBI3 in the IL-12p70 producing cell line effectively suppressed IL-12p70 production. IL-35 secretion was also detected in the cell line, with suppressed IL-12p70 production by immune-precipitation Western blotting. However, this secretion was not evident in M2 macrophages following stimulation by HKC. This can be explained by the constitutive expression of IL-35 receptors (gp130 and IL-12R?2) in M2 macrophages for cytokine consumption. Our results have indicated that C. albicans can suppress host inflammatory responses in mucosal skin by suppressing LPS-induced IL-12p70 production. Lower IL-12p70 production may avoid an unnecessary Th1 response in order to retain immune tolerance, which may be one of the mechanisms by which C. albicans achieves a successful commensal lifestyle without having a detrimental effect on the hosts health.
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Influence of age and aerobic fitness on the multifractal characteristics of electrocardiographic RR time-series.
Front Physiol
PUBLISHED: 01-01-2013
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Multifractal properties of electrocardiographic inter-beat (RR) time-series offer insight into its long-term correlation structure, independently of RR variability. Here we quantify multifractal characteristics of RR data during 24-h diurnal-nocturnal activity in healthy participants. We tested the hypotheses that (1) age, gender and aerobic fitness influence RR multifractal properties, and that (2) these are influenced by circadian variation. Seventy adults (39 males) aged 19-58 years and of various fitness levels were monitored using 24-h ECG. Participants were dichotomized by median age and fitness for sub-group analysis. Gender and fitness were independent of age (p = 0.1, p > 0.5). Younger/older group ages were substantially different (p < 0.0005) and were independent of gender and fitness. Multifractality was quantified using the probability spectrum of Hölder exponents (h), from which modal h (h(*)) and the full-width and half-widths at half-maximum measures (FWHM, HWHM+, and HWHM-) were derived. FWHM decreased (p = 0.004) and h(*) increased (p = 0.011) in older people, indicating diminished long-range RR correlations and weaker anti-persistent behavior. Anti-persistent correlation (h(*)) was strongest in the youngest/fittest individuals and weakest in the oldest/least fit individuals (p = 0.015). Long-range correlation (HWHM+/FWHM) was strongest in the fittest males and weakest in the least fit females (p = 0.007-0.033). Multifractal RR characteristics in our healthy participants showed strong age-dependence, with diminished long-range anti-persistent correlation in older people. Circadian variation of these characteristics was influenced by fitness and gender: fitter males and females of all ages had the greatest degree of multifractality or long-range order. Multifractal characterization appears to be a useful method for exploring the physiological basis of long-term correlation structure in RR time-series as well as the benefits thereon of physical fitness training.
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Neuroprotection for the warrior: dietary supplementation with omega-3 fatty acids.
Mil Med
PUBLISHED: 12-02-2011
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Nutrition has traditionally involved in supplying energy and hydration. An emerging concept developed by the authors is the concept of using omega-3 fatty acids (n-3 FAs) to increase the resilience of the brain. The n-3 FAs have numerous proven benefits including support of cardiovascular and psychiatric health. Docosahexaenoic acid in particular, is found in high concentrations in the brain. N-3 FAs provide benefits by exerting a protective mechanism at the cellular and neuronal levels including the modulation of inflammatory cascade following traumatic brain injury. Promising research and evolving clinical experience now indicate that n-3 FA is useful and effective for recovery following traumatic brain injury. More exciting is that new laboratory research shows the beneficial effects extend to when n-3 FA is given before injury. Given the safety profile, availability, and affordability of n-3 FA, Generally Recognized As Safe amounts of eicosapentaenoic acid and docosahexaenoic acid (up to 3,000 mg daily) should be considered for the athlete and soldier, not only for its general health benefits, but particularly also for those at risk or high exposure to brain impacts. A comprehensive, coordinated research program to evaluate the multiple uses of n-3 FA should be a high priority for the Department of Defense.
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Comparison of pretargeted and conventional CC49 radioimmunotherapy using 149Pm, 166Ho, and 177Lu.
Bioconjug. Chem.
PUBLISHED: 11-14-2011
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The therapeutic efficacies of radiolabeled biotin, pretargeted by monoclonal antibody (mAb)-streptavidin fusion protein CC49 scFvSA, were compared to those of radiolabeled mAb CC49, using the three radiolanthanides in an animal model of human colon cancer. The purpose of the present study was to compare antibody pretargeting to conventional radioimmunotherapy using (149)Pm, (166)Ho, or (177)Lu. Nude mice bearing LS174T colon tumors were injected sequentially with CC49 scFvSA, the blood clearing agent biotin-GalNAc(16), and (149)Pm-, (166)Ho-, or (177)Lu-DOTA-biotin. Tumor-bearing mice were alternatively administered (149)Pm-, (166)Ho-, or (177)Lu-MeO-DOTA-CC49. Therapy with pretargeted (149)Pm-,(166)Ho-, and (177)Lu-DOTA-biotin increased the median time of progression to a 1 g tumor to 50, 41, and 50 days post-treatment, respectively. Therapy with (149)Pm-,(166)Ho-, and (177)Lu-MeO-DOTA-CC49 increased the median time to progression to 53, 24, and 67 days post-treatment, respectively. In contrast, saline controls showed a median time to progression of 13 days postinjection. Treatment with pretargeted (149)Pm-, (166)Ho-, and (177)Lu-biotin or (149)Pm-, (166)Ho-, and (177)Lu-CC49 increased tumor doubling time to 18-36 days, compared to 3 days for saline controls. Among treated mice, 23% survived >84 days post-therapy, and 11% survived 6 months, but controls survived <29 days. Long-term survivors showed tumor growth inhibition or partial regression, extensive necrosis in residual masses, and no evidence of nontarget tissue toxicity at necropsy. Both pretargeted and conventional RIT demonstrated considerable efficacy in an extremely aggressive animal model of cancer. Our results identified (177)Lu as an optimal radiolanthanide for future evaluation of these agents in toxicity and multiple-dose therapy studies.
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ID4 regulates mammary gland development by suppressing p38MAPK activity.
Development
PUBLISHED: 11-10-2011
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The ID family of helix-loop-helix proteins regulates cell proliferation and differentiation in many different developmental pathways, but the functions of ID4 in mammary development are unknown. We report that mouse Id4 is expressed in cap cells, basal cells and in a subset of luminal epithelial cells, and that its targeted deletion impairs ductal expansion and branching morphogenesis as well as cell proliferation induced by estrogen and/or progesterone. We discover that p38MAPK is activated in Id4-null mammary cells. p38MAPK is also activated following siRNA-mediated Id4 knockdown in transformed mammary cells. This p38MAPK activation is required for the reduced proliferation and increased apoptosis in Id4-ablated mammary glands. Therefore, ID4 promotes mammary gland development by suppressing p38MAPK activity.
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Metabolic and morphometric profile of muscle fibers in chronic hemodialysis patients.
J. Appl. Physiol.
PUBLISHED: 10-20-2011
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Muscle weakness and effort intolerance are common in maintenance hemodialysis (MHD) patients. This study characterized morphometric, histochemical, and biochemical properties of limb muscle in MHD patients compared with controls (CTL) with similar age, gender, and ethnicity. Vastus lateralis muscle biopsies were obtained from 60 MHD patients, 1 day after dialysis, and from 21 CTL. Muscle fiber types and capillaries were identified immunohistochemically. Individual muscle fiber cross-sectional areas (CSA) were quantified. Individual fiber oxidative capacities were determined (microdensitometric assay) to measure succinate dehydrogenase (SDH) activity. Mean CSAs of type I, IIA, and IIX fibers were 33, 26, and 28% larger in MHD patients compared with CTL. SDH activities for type I, IIA, and IIX fibers were reduced by 29, 40, and 47%, respectively, in MHD. Capillary to fiber ratio was increased by 11% in MHD. The number of capillaries surrounding individual fiber types were also increased (type I: 9%; IIA: 10%; IIX: 23%) in MHD patients. However, capillary density (capillaries per unit muscle fiber area) was reduced by 34% in MHD patients, compared with CTL. Ultrastuctural analysis revealed swollen mitochondria with dense matrix in MHD patients. These results highlight impaired oxidative capacity and capillarity in MHD patients. This would be expected to impair energy production as well as substrate and oxygen delivery and exchange and contribute to exercise intolerance. The enlarged CSA of muscle fibers may, in part, be accounted for by edema. We speculate that these changes contribute to reduce limb strength in MHD patients by reducing specific force.
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Review of guidelines for the prevention and treatment of infection in patients with an absent or dysfunctional spleen: prepared on behalf of the British Committee for Standards in Haematology by a working party of the Haemato-Oncology task force.
Br. J. Haematol.
PUBLISHED: 10-13-2011
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Guidelines for the prevention and treatment of infection in patients with an absent or dysfunctional spleen were first published by the British Committee for Standards in Haematology (BCSH) in 1996 and formally reviewed in 2002. Although the guidelines originated from discussion within the BCSH, the intended readership is wide given the multidisciplinary nature of the management of hyposplenism.
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Candidate targets for Multilocus Sequence Typing of Trypanosoma cruzi: validation using parasite stocks from the Chaco Region and a set of reference strains.
Infect. Genet. Evol.
PUBLISHED: 10-12-2011
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A Multilocus Sequence Typing (MLST) scheme was designed and applied to a set of 20 Trypanosoma cruzi stocks belonging to three main discrete typing units (T. cruzi I, V and VI) from a geographically restricted Chagas disease endemic area in Argentina, 12 reference strains comprising two from each of the six main discrete typing units of the parasite (T. cruzi I-VI), and one T. cruzi marinkellei strain. DNA fragments (?400-bp) from 10 housekeeping genes were sequenced. A total of 4178 bp were analyzed for each stock. In all, 154 polymorphic sites were identified. Ninety-five sites were heterozygous in at least one analyzed stock. Seventeen diploid sequence types were identified from 32 studied T. cruzi stocks (including the reference strains). All stocks were correctly assigned to their corresponding discrete typing units. We propose this MLST scheme as provisional, with scope for improvement by studying new gene targets on a more diverse sample of stocks, in order to define an optimized MLST scheme for T. cruzi. This approach is an excellent candidate to become the gold standard for T. cruzi genetic typing. We suggest that MLST will have a strong impact on molecular epidemiological studies of Chagas disease and the phylogenetics of its causative agent.
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In vitro evaluation of targeted antisense 177Lu radiotherapy.
Anticancer Res.
PUBLISHED: 10-04-2011
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The BCL2 proto-oncogene in non-Hodgkins lymphoma is a dominant inhibitor of apoptosis. The goal of this work was to develop a (177)Lu-labeled anti-BCL2-peptide nucleic acid (PNA) conjugate designed for dual modality NHL therapy, i.e., simultaneous down-regulation of BCL2-mediated resistance to apoptosis and delivery of cytotoxic internally emitted radiation.
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Variations in the anatomical distribution of peripheral vascular disease according to gender.
Ann R Coll Surg Engl
PUBLISHED: 09-28-2011
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While large epidemiological studies have suggested that the male gender is more frequently afflicted with intermittent claudication, there is little data whether there are gender differences in the distribution of peripheral vascular disease (PVD). The aim of this study was to clarify this issue on the basis of angiographic findings in patients presenting with claudication.
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Mineral partitioning in milk and milk permeates at high temperature.
J. Dairy Res.
PUBLISHED: 09-13-2011
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The soluble phase of milk was separated at 20 and 80 °C using ultrafiltration. The resulting permeates were then subjected to further ultrafiltration and dialysis at close to these two temperatures. It was found that pH, Ca2+ and soluble Ca decreased as the separation temperature increased both in original UF permeates and in dialysates obtained from these permeates, but P decreased only slightly. The major reason for these changes was due to the precipitation of calcium phosphate/citrate complexes onto the casein micelle with concomitant release of H+. The pH of both permeates and dialysates from milk at 20 °C were slightly higher than for milk. When UF permeates collected at 20 and 80 °C, were each dialysed at both these temperatures, the dialysate collected at 80 °C showed much less temperature dependence for pH and ionic calcium compared with that collected at 20 °C. This is in contrast to milk, which shows considerable temperature dependence for pH and ionic calcium. Further experiments revealed that the pH and Ca2+ concentration of permeates showed high temperature dependence above the temperature at which they were separated, but a much lower temperature dependence below that temperature. These findings suggest that dialysis and UF of milk at high temperature provide the best means yet for estimating the pH and ionic calcium of milk at that temperature.
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A fractionation of the physiological burden of the personal protective equipment worn by firefighters.
Eur. J. Appl. Physiol.
PUBLISHED: 09-08-2011
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Load carriage increases physiological strain, reduces work capacity and elevates the risk of work-related injury. In this project, the separate and combined physiological consequences of wearing the personal protective equipment used by firefighters were evaluated. The overall impact upon performance was first measured in 20 subjects during a maximal, job-related obstacle course trial and an incremental treadmill test to exhaustion (with and without protective equipment). The fractional contributions of the thermal protective clothing, helmet, breathing apparatus and boots were then separately determined during steady-state walking (4.8 km h(-1), 0% gradient) and bench stepping (20 cm at 40 steps min(-1)). The protective equipment reduced exercise tolerance by 56% on a treadmill, with the ambulatory oxygen consumption reserve (peak minus steady-state walking) being 31% lower. For the obstacle course, performance declined by 27%. Under steady-state conditions, the footwear exerted the greatest relative metabolic impact during walking and bench stepping, being 8.7 and 6.4 times greater per unit mass than the breathing apparatus. Indeed, the relative influence of the clothing on oxygen cost was at least three times that of the breathing apparatus. Therefore, the most efficient way to reduce the physiological burden of firefighters protective equipment, and thereby increase safety, would be to reduce the mass of the boots and thermal protective clothing.
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Dicer-mediated upregulation of BCRP confers tamoxifen resistance in human breast cancer cells.
Clin. Cancer Res.
PUBLISHED: 08-30-2011
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Tamoxifen (Tam) is the most prescribed hormonal agent for treatment of estrogen receptor ? (ER?)-positive breast cancer patients. Using microarray analysis, we observed that metastatic breast tumors resistant to Tam therapy had elevated levels of Dicer.
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Cisplatin@US-tube carbon nanocapsules for enhanced chemotherapeutic delivery.
Biomaterials
PUBLISHED: 08-25-2011
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The use of chemotherapeutic drugs in cancer therapy is often limited by problems with administration such as insolubility, inefficient biodistribution, lack of selectivity, and inability of the drug to cross cellular barriers. To overcome these limitations, various types of drug delivery systems have been explored, and recently, carbon nanotube (CNT) materials have also garnered attention in the area of drug delivery. In this study, we describe the preparation, characterization, and in vitro testing of a new ultra-short single-walled carbon nanotube (US-tube)-based drug delivery system for the treatment of cancer. In particular, the encapsulation of cisplatin (CDDP), a widely-used anticancer drug, within US-tubes has been achieved, and the resulting CDDP@US-tube material characterized by high-resolution transmission electron microscopy (HR-TEM), energy-dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), and inductively-coupled optical emission spectrometry (ICP-OES). Dialysis studies performed in phosphate-buffered saline (PBS) at 37 °C have demonstrated that CDDP release from CDDP@US-tubes can be controlled (retarded) by wrapping the CDDP@US-tubes with Pluronic-F108 surfactant. Finally, the anticancer activity of pluronic-wrapped CDDP@US-tubes has been evaluated against two different breast cancer cell lines, MCF-7 and MDA-MB-231, and found to exhibit enhanced cytotoxicity over free CDDP after 24 h. These studies have laid the foundation for developing US-tube-based delivery of chemotherapeutics, with drug release mainly limited to within cancer cells only.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

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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.