275 research outputs found

    Wild and aquaculture populations of the eastern oyster compared using microsatellites

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    Five new microsatellite markers were developed for the eastern oyster (Crassostrea virginica), and allelic variability was compared between a wild Chesapeake Bay population (James River) and a hatchery strain (DEBY (TM)). All loci amplified readily and demonstrated allelic variability with the number of alleles ranging from 16 to 36 in the wild population and from 11 to 19 in the DEBY (TM) strain. Average observed and expected heterozygosities were estimated at 0.66 and 0.80 in the hatchery sample. The corresponding estimates were 0.91 and 0.75 in the wild sample. Results indicated lower genetic variability in the DEBY (TM) strain and significant genetic differentiation between the wild population and hatchery strain. These microsatellite loci will prove valuable for future population genetic studies and in tracking of hatchery strains used in restoration

    Exogenous glycosaminoglycans coat damaged bladder surfaces in experimentally damaged mouse bladder

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    BACKGROUND: Interstital cystitis is often treated with exogenous glycosaminoglycans such as heparin, chondroitin sulphate (Uracyst), hyaluronate (Cystistat) or the semi-synthetic pentosan polysulphate (Elmiron). The mechanism of action is presumed to be due to a coating of the bladder surface to replace the normally present chondroitin sulphate and heparan sulphate lost as a result of the disease. This study used fluorescent labelled chondroitin sulphate to track the distribution of glycosaminoglycans administered intravesically to mouse bladder that had been damaged on the surface. METHODS: The surfaces of mouse bladders were damaged by 3 mechanisms – trypsin, 10 mM HCl, and protamine sulphate. Texas Red-labeled chondroitin sulphate was instilled into the bladders of animals with damaged bladders and controls instilled only with saline. Bladders were harvested, frozen, and sectioned for examination by fluorescence. RESULTS: The normal mouse bladder bound a very thin layer of the labelled chondroitin sulphate on the luminal surface. Trypsin- and HCl-damaged bladders bound the labelled chondroitin sulphate extensively on the surface with little penetration into the bladder muscle. Protamine produced less overt damage, and much less labelling was seen, presumably due to loss of the label as it complexed with the protamine intercalated into the bladder surface. CONCLUSION: Glycosaminoglycan administered intravesically does bind to damaged bladder. Given that the changes seen following bladder damage resemble those seen naturally in interstitial cystitis, the mechanisms proposed for the action of these agents is consistent with a coating of damaged bladder

    Histone deacetylase adaptation in single ventricle heart disease and a young animal model of right ventricular hypertrophy.

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    BackgroundHistone deacetylase (HDAC) inhibitors are promising therapeutics for various forms of cardiac diseases. The purpose of this study was to assess cardiac HDAC catalytic activity and expression in children with single ventricle (SV) heart disease of right ventricular morphology, as well as in a rodent model of right ventricular hypertrophy (RVH).MethodsHomogenates of right ventricle (RV) explants from non-failing controls and children born with a SV were assayed for HDAC catalytic activity and HDAC isoform expression. Postnatal 1-day-old rat pups were placed in hypoxic conditions, and echocardiographic analysis, gene expression, HDAC catalytic activity, and isoform expression studies of the RV were performed.ResultsClass I, IIa, and IIb HDAC catalytic activity and protein expression were elevated in the hearts of children born with a SV. Hypoxic neonatal rats demonstrated RVH, abnormal gene expression, elevated class I and class IIb HDAC catalytic activity, and protein expression in the RV compared with those in the control.ConclusionsThese data suggest that myocardial HDAC adaptations occur in the SV heart and could represent a novel therapeutic target. Although further characterization of the hypoxic neonatal rat is needed, this animal model may be suitable for preclinical investigations of pediatric RV disease and could serve as a useful model for future mechanistic studies

    A train-the-trainer education and promotion program: chronic fatigue syndrome – a diagnostic and management challenge

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    <p>Abstract</p> <p>Background</p> <p>Chronic fatigue syndrome (CFS) is a complicated illness for providers and patients. Fewer than 20% of persons with CFS have been diagnosed and treated. For providers, compounding the issue are the challenges in making a diagnosis due to the lack of a biomedical marker.</p> <p>Methods</p> <p>The objective of the CFS diagnosis and management curriculum was to instruct core trainers as to the evaluation, diagnosis, and management of CFS. Over a two year period, 79 primary care physicians, physician assistants, and nurse practitioners from diverse regions in the U.S. participated as core trainers in a two day Train-the-Trainer (TTT) workshop. As core trainers, the workshop participants were expected to show increases in knowledge, self-efficacy, and management skills with the primary goal of conducting secondary presentations.</p> <p>Results</p> <p>The optimal goal for each core trainer to present secondary training to 50 persons in the health care field was not reached. However, the combined core trainer group successfully reached 2064 primary care providers. Eighty-two percent of core trainers responded "Very good" or "Excellent" in a post-tessurvey of self-efficacy expectation and CFS diagnosis. Data from the Chicago workshops showed significant improvement on the Primary Care Opinion Survey (p < 0.01) and on the Relevance and Responsibility Factors of the CAT survey (p = 0.03 and p = 0.04, respectively). Dallas workshop data show a significant change from pre- to post-test scores on the CFS Knowledge test (p = 0.001). Qualitative and process evaluation data revealed that target audience and administrative barriers impacted secondary training feasibility.</p> <p>Conclusion</p> <p>Data show the workshop was successful in meeting the objectives of increasing CFS knowledge and raising perceived self-efficacy towards making a diagnosis. The CFS TTT program informed an educational provider project by shifting the format for physicians to grand rounds and continuing medical education design while retaining TTT aspects for nurse practitioners and physicians assistants. Evaluations also indicate that secondary trainings may be more readily employed and accepted if administrative barriers are addressed early in the planning phases.</p

    Body mass index, physical activity, and dietary behaviors among members of an urban community fitness center: a questionnaire survey

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    <p>Abstract</p> <p>Background</p> <p>Development of effective behavioral interventions to promote weight control and physical activity among diverse, underserved populations is a public health priority. Community focused wellness organizations, such as YMCAs, could provide a unique channel with which to reach such populations. This study assessed health behaviors and related characteristics of members of an urban YMCA facility.</p> <p>Methods</p> <p>We surveyed 135 randomly selected members of an urban YMCA facility in Massachusetts to examine self-reported (1) physical activity, (2) dietary behaviors, (3) body mass index, and (4) correlates of behavior change among short-term (i.e., one year or less) and long-term (i.e., more than one year) members. Chi-square tests were used to assess bivariate associations between variables, and multivariate linear regression models were fit to examine correlates of health behaviors and weight status.</p> <p>Results</p> <p>Eighty-nine percent of short-term and 94% of long-term members reported meeting current physical activity recommendations. Only 24% of short-term and 19% of long-term members met fruit and vegetable consumption recommendations, however, and more than half were overweight or obese. Length of membership was not significantly related to weight status, dietary behaviors, or physical activity. Most respondents were interested in changing health behaviors, in the preparation stage of change, and had high levels of self-efficacy to change behaviors. Short-term members had less education (p = 0.02), lower household incomes (p = 0.02), and were less likely to identify as white (p = 0.005) than long-term members. In multivariate models, females had lower BMI than males (p = 0.003) and reported less physical activity (p = 0.008). Physical activity was also inversely associated with age (p = 0.0004) and education (p = 0.02).</p> <p>Conclusion</p> <p>Rates of overweight/obesity and fruit and vegetable consumption suggested that there is a need for a weight control intervention among members of an urban community YMCA. Membership in such a community wellness facility alone might not be sufficient to help members maintain a healthy weight. The data indicate that YMCA members are interested in making changes in their dietary and physical activity behaviors. Targeting newer YMCA members might be an effective way of reaching underserved populations. These data will help inform the development of a weight control intervention tailored to this setting.</p

    The Na+/H+ Exchanger Controls Deoxycholic Acid-Induced Apoptosis by a H+-Activated, Na+-Dependent Ionic Shift in Esophageal Cells

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    Apoptosis resistance is a hallmark of cancer cells. Typically, bile acids induce apoptosis. However during gastrointestinal (GI) tumorigenesis the cancer cells develop resistance to bile acid-induced cell death. To understand how bile acids induce apoptosis resistance we first need to identify the molecular pathways that initiate apoptosis in response to bile acid exposure. In this study we examined the mechanism of deoxycholic acid (DCA)-induced apoptosis, specifically the role of Na+/H+ exchanger (NHE) and Na+ influx in esophageal cells. In vitro studies revealed that the exposure of esophageal cells (JH-EsoAd1, CP-A) to DCA (0.2 mM -0.5 mM) caused lysosomal membrane perturbation and transient cytoplasmic acidification. Fluorescence microscopy in conjunction with atomic absorption spectrophotometry demonstrated that this effect on lysosomes correlated with influx of Na+, subsequent loss of intracellular K+, an increase of Ca2+ and apoptosis. However, ethylisopropyl-amiloride (EIPA), a selective inhibitor of NHE, prevented Na+, K+ and Ca2+ changes and caspase 3/7 activation induced by DCA. Ouabain and amphotericin B, two drugs that increase intracellular Na+ levels, induced similar changes as DCA (ion imbalance, caspase3/7 activation). On the contrary, DCA-induced cell death was inhibited by medium with low a Na+ concentrations. In the same experiments, we exposed rat ileum ex-vivo to DCA with or without EIPA. Severe tissue damage and caspase-3 activation was observed after DCA treatment, but EIPA almost fully prevented this response. In summary, NHE-mediated Na+ influx is a critical step leading to DCA-induced apoptosis. Cells tolerate acidification but evade DCA-induced apoptosis if NHE is inhibited. Our data suggests that suppression of NHE by endogenous or exogenous inhibitors may lead to apoptosis resistance during GI tumorigenesis

    Shipping blood to a central laboratory in multicenter clinical trials: effect of ambient temperature on specimen temperature, and effects of temperature on mononuclear cell yield, viability and immunologic function

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    <p>Abstract</p> <p>Background</p> <p>Clinical trials of immunologic therapies provide opportunities to study the cellular and molecular effects of those therapies and may permit identification of biomarkers of response. When the trials are performed at multiple centers, transport and storage of clinical specimens become important variables that may affect lymphocyte viability and function in blood and tissue specimens. The effect of temperature during storage and shipment of peripheral blood on subsequent processing, recovery, and function of lymphocytes is understudied and represents the focus of this study.</p> <p>Methods</p> <p>Peripheral blood samples (n = 285) from patients enrolled in 2 clinical trials of a melanoma vaccine were shipped from clinical centers 250 or 1100 miles to a central laboratory at the sponsoring institution. The yield of peripheral blood mononuclear cells (PBMC) collected before and after cryostorage was correlated with temperatures encountered during shipment. Also, to simulate shipping of whole blood, heparinized blood from healthy donors was collected and stored at 15°C, 22°C, 30°C, or 40°C, for varied intervals before isolation of PBMC. Specimen integrity was assessed by measures of yield, recovery, viability, and function of isolated lymphocytes. Several packaging systems were also evaluated during simulated shipping for the ability to maintain the internal temperature in adverse temperatures over time.</p> <p>Results</p> <p>Blood specimen containers experienced temperatures during shipment ranging from -1 to 35°C. Exposure to temperatures above room temperature (22°C) resulted in greater yields of PBMC. Reduced cell recovery following cryo-preservation as well as decreased viability and immune function were observed in specimens exposed to 15°C or 40°C for greater than 8 hours when compared to storage at 22°C. There was a trend toward improved preservation of blood specimen integrity stored at 30°C prior to processing for all time points tested. Internal temperatures of blood shipping containers were maintained longer in an acceptable range when warm packs were included.</p> <p>Conclusions</p> <p>Blood packages shipped overnight by commercial carrier may encounter extreme seasonal temperatures. Therefore, considerations in the design of shipping containers should include protecting against extreme ambient temperature deviations and maintaining specimen temperature above 22°C or preferably near 30°C.</p

    The use of gamma-irradiation and ultraviolet-irradiation in the preparation of human melanoma cells for use in autologous whole-cell vaccines

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    <p>Abstract</p> <p>Background</p> <p>Human cancer vaccines incorporating autologous tumor cells carry a risk of implantation and subsequent metastasis of viable tumor cells into the patient who is being treated. Despite the fact that the melanoma cell preparations used in a recent vaccine trial (Mel37) were gamma-irradiated (200 Gy), approximately 25% of the preparations failed quality control release criteria which required that the irradiated cells incorporate <sup>3</sup>H-thymidine at no more than 5% the level seen in the non-irradiated cells. We have, therefore, investigated ultraviolet (UV)-irradiation as a possible adjunct to, or replacement for gamma-irradiation.</p> <p>Methods</p> <p>Melanoma cells were gamma- and/or UV-irradiated. <sup>3</sup>H-thymidine uptake was used to assess proliferation of the treated and untreated cells. Caspase-3 activity and DNA fragmentation were measured as indicators of apoptosis. Immunohistochemistry and Western blot analysis was used to assess antigen expression.</p> <p>Results</p> <p>UV-irradiation, either alone or in combination with gamma-irradiation, proved to be extremely effective in controlling the proliferation of melanoma cells. In contrast to gamma-irradiation, UV-irradiation was also capable of inducing significant levels of apoptosis. UV-irradiation, but not gamma-irradiation, was associated with the loss of tyrosinase expression. Neither form of radiation affected the expression of gp100, MART-1/MelanA, or S100.</p> <p>Conclusion</p> <p>These results indicate that UV-irradiation may increase the safety of autologous melanoma vaccines, although it may do so at the expense of altering the antigenic profile of the irradiated tumor cells.</p

    The Frequency of Malaria Is Similar among Women Receiving either Lopinavir/Ritonavir or Nevirapine-based Antiretroviral Treatment

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    HIV protease inhibitors (PIs) show antimalarial activity in vitro and in animals. Whether this translates into a clinical benefit in HIV-infected patients residing in malaria-endemic regions is unknown. We studied the incidence of malaria, as defined by blood smear positivity or a positive Plasmodium falciparum histidine-rich protein 2 antigen test, among 444 HIV-infected women initiating antiretroviral treatment (ART) in the OCTANE trial (A5208; ClinicalTrials.gov: NCT00089505). Participants were randomized to treatment with PI-containing vs. PI-sparing ART, and were followed prospectively for ≥48 weeks; 73% also received cotrimoxazole prophylaxis. PI-containing treatment was not associated with protection against malaria in this study population
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