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We used self‐reported data from United Methodist clergy to assess the prevalence of obesity and having ever been told certain chronic disease diagnoses. Of all actively serving United Methodist clergy in North Carolina (NC) 95% (n = 1726) completed self‐report height and weight items and diagnosis questions from the Behavioral Risk Factor Surveillance Survey (BRFSS). We calculated BMI categories and diagnosis prevalence rates for the clergy and compared them to the NC population using BRFSS data. The obesity rate among clergy aged 35–64 years was 39.7%, 10.3% (95% CI = 8.5%, 12.1%) higher than their NC counterparts. Clergy also reported significantly higher rates of having ever been given diagnoses of diabetes, arthritis, high blood pressure, angina, and asthma compared to their NC peers. Health interventions that address obesity and chronic disease among clergy are urgently needed.  相似文献   
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A new study of divergence in freshwater fish provides strong evidence of rapid, temperature-mediated adaptation. This study is particularly important in the ongoing debate over the extent and significance of evolutionary response to climate change because divergence has occurred in relatively few generations in spite of ongoing gene flow and in the aftermath of a significant genetic bottleneck, factors that have previously been considered obstacles to evolution. Climate change may thus be more likely to foster contemporary evolutionary responses than has been anticipated, and I argue here for the importance of investigating their possible occurrence.  相似文献   
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Cyclic GMP causes the release of endogenous Ca2+ from rod outer segments, whose plasma membrane has been made permeable, or from isolated discs. Approximately 11,000 Ca2+ ions are released per disc at saturating concentrations of cyclic GMP. The velocity and the amplitude of the release of Ca2+ are dependent on the concentration of cyclic GMP. The maximal rate of the Ca2+ efflux is approximately 7 X 10(4) Ca2+ ions s-1 rod-1. The Ca2+ release by cyclic GMP is independent of light. The activation of the efflux occurred within a narrow range of the cyclic GMP concentration (30-80 microM) and does not obey a simple Michaelis-Menten scheme. Instead, the kinetic analysis of the Ca2+ efflux suggests that a minimum number of 2 molecules of cyclic GMP activates the ion conductance in a cooperative fashion. The release of Ca2+ by cyclic GMP requires a gradient of Ca2+ ions across the disc membrane. If the endogenous Ca2+ gradient is dissipated by means of the ionophore A23187, the release of Ca2+ by cyclic GMP is abolished. Ca2+ is released by analogues of cyclic GMP which are either modified at the 8-carbon position of the imidazole ring or by the deaza-analogue of cyclic GMP. Congeners of cyclic GMP which are modified at the ribose, phosphodiester, or pyrimidine portion of the molecule are ineffective. The hydrolysis of cyclic GMP by the light-regulated phosphodiesterase of rod outer segments is not a necessary condition for the Ca2+ release because 8-bromo-cyclic GMP, a congener resistant to hydrolysis, is a more powerful activator of the release than cyclic GMP itself. Ca2+ release by cyclic GMP is inhibited by organic and inorganic blockers of Ca2+ channels. The l-stereoisomer of cis-diltiazem blocks the release of Ca2+ at micromolar concentrations, whereas the d-form is much less effective. These results suggest that disc membranes contain a cationic conductance which is permeable to Ca2+ ions and which is regulated through the cooperative binding of at least 2 molecules of cyclic GMP to regulatory sites of the transport protein. By this mechanism, subtle changes in the concentration of cyclic GMP could promote large changes in the flux of Ca2+ ions across the disc membrane.  相似文献   
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  1. Assemblages of insect herbivores are structured by plant traits such as nutrient content, secondary metabolites, physical traits, and phenology. Many of these traits are phylogenetically conserved, implying a decrease in trait similarity with increasing phylogenetic distance of the host plant taxa. Thus, a metric of phylogenetic distances and relationships can be considered a proxy for phylogenetically conserved plant traits and used to predict variation in herbivorous insect assemblages among co‐occurring plant species.
  2. Using a Holarctic dataset of exposed‐feeding and shelter‐building caterpillars, we aimed at showing how phylogenetic relationships among host plants explain compositional changes and characteristics of herbivore assemblages.
  3. Our plant–caterpillar network data derived from plot‐based samplings at three different continents included >28,000 individual caterpillar–plant interactions. We tested whether increasing phylogenetic distance of the host plants leads to a decrease in caterpillar assemblage overlap. We further investigated to what degree phylogenetic isolation of a host tree species within the local community explains abundance, density, richness, and mean specialization of its associated caterpillar assemblage.
  4. The overlap of caterpillar assemblages decreased with increasing phylogenetic distance among the host tree species. Phylogenetic isolation of a host plant within the local plant community was correlated with lower richness and mean specialization of the associated caterpillar assemblages. Phylogenetic isolation had no effect on caterpillar abundance or density. The effects of plant phylogeny were consistent across exposed‐feeding and shelter‐building caterpillars.
  5. Our study reveals that distance metrics obtained from host plant phylogeny are useful predictors to explain compositional turnover among hosts and host‐specific variations in richness and mean specialization of associated insect herbivore assemblages in temperate broadleaf forests. As phylogenetic information of plant communities is becoming increasingly available, further large‐scale studies are needed to investigate to what degree plant phylogeny structures herbivore assemblages in other biomes and ecosystems.
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Atherosclerosis and its consequences remain prevalent clinical challenges throughout the world. Initiation and progression of atherosclerosis involves a complex, dynamic interplay among inflammation, hyperlipidemia, and endothelial dysfunction. A multicomponent treatment approach targeted for delivery within diseased vessels could prove beneficial in treating atherosclerosis. This study was undertaken to evaluate the multimodal effects of a novel ω-3-fatty acid-rich, 17-β-estradiol (17-βE)-loaded, CREKA-peptide-modified nanoemulsion system on experimental atherosclerosis. In vitro treatment of cultured human aortic endothelial cells (ECs) with the 17-βE-loaded, CREKA-peptide-modified nanoemulsion system increased cellular nitrate/nitrite, indicating improved nitric oxide formation. In vivo, systemic administration of this nanoemulsion system to apolipoprotein-E knock out (ApoE-/-) mice fed a high-fat diet significantly improved multiple parameters related to the etiology and development of occlusive atherosclerotic vasculopathy: lesion area, circulating plasma lipid levels, and expression of aortic-wall inflammatory markers. These salutary effects were attributed selectively to the 17-βE and/or ω-3 polyunsaturated fatty acid components of the nano-delivery system. At therapeutic doses, the 17-βE-loaded, CREKA-peptide modified nanoemulsion system appeared to be biocompatible in that it elicited no apparent adverse/toxic effects, as indexed by body weight, plasma alanine aminotransferase/aspartate aminotransferase levels, and liver and kidney histopathology. The study demonstrates the therapeutic potential of a novel, 17-βE-loaded, CREKA-peptide-modified nanoemulsion system against atherosclerosis in a multimodal fashion by reducing lesion size, lowering the levels of circulating plasma lipids and decreasing the gene expression of inflammatory markers associated with the disease.  相似文献   
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Generalist predators have the capacity to restrict pest population growth, especially early in the season before densities increase. However, their polyphagous feeding habits sometimes translate into reduced pest consumption when they target alternative prey. An order-specific monoclonal antibody was developed to examine the strength of trophic connections between Diptera, a major category of non-pest prey, and linyphiid spiders in alfalfa. We report the development and characterization of a monoclonal antibody with order-level specificity to Diptera. This antibody elicited strong absorbance to 22 Diptera from 13 families, no false-positive reactivity to non-dipteran invertebrates, and antigen detection periods following prey consumption that were comparable between spiders. Over 900 field-collected females of the linyphiid spiders Erigone autumnalis and Bathyphantes pallidus were screened for Diptera antigen. Significantly more B. pallidus screened positive for Diptera (40%) compared to E. autumnalis (16%), indicating differential reliance on these prey. In parallel with the collection of spiders for gut-content analysis, prey availability was estimated at web sites. The two spiders exhibited different feeding responses to prey availability. Consumption of Diptera by B. pallidus was strongly correlated with Diptera abundance whilst the availability of other potential prey did not influence predation rates. Conversely, E. autumnalis did not prey upon Diptera in proportion to availability, but increased Collembola activity-density reduced dipteran consumption. Integration of molecular gut-content analysis with precise sampling of prey demonstrated how two closely related linyphiid spiders exhibit different feeding responses to the availability of prey under natural field conditions. Elucidating the feeding preferences of natural enemies is critical to effective incorporation of biological control by generalist predators in the management of agricultural pests.  相似文献   
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