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861.
Tomá? Venit Rastislav Dzijak Al?běta Kalendová Michal Kahle Jana Roho?ková Volker Schmidt Thomas Rülicke Birgit Rathkolb Wolfgang Hans Alexander Bohla Oliver Eickelberg Tobias Stoeger Eckhard Wolf Ali ?nder Yildirim Valérie Gailus-Durner Helmut Fuchs Martin Hrabě de Angelis Pavel Hozák 《PloS one》2013,8(4)
862.
David Mansouri Donald C. McMillan Yasmin Grant Emilia M. Crighton Paul G. Horgan 《PloS one》2013,8(6)
Background
Population-based colorectal cancer screening has been shown to reduce cancer specific mortality and is used across the UK. Despite evidence that older age, male sex and deprivation are associated with an increased incidence of colorectal cancer, uptake of bowel cancer screening varies across demographic groups. The aim of this study was to assess the impact of age, sex and deprivation on outcomes throughout the screening process.Methods
A prospectively maintained database, encompassing the first screening round of a faecal occult blood test screening programme in a single geographical area, was analysed.Results
Overall, 395 096 individuals were invited to screening, 204 139 (52%) participated and 6 079 (3%) tested positive. Of the positive tests, 4 625 (76%) attended for colonoscopy and cancer was detected in 396 individuals (9%). Lower uptake of screening was associated with younger age, male sex and deprivation (all p<0.001). Only deprivation was associated with failure to proceed to colonoscopy following a positive test (p<0.001). Despite higher positivity rates in those that were more deprived (p<0.001), the likelihood of detecting cancer in those attending for colonoscopy was lower (8% most deprived vs 10% least deprived, p = 0.003).Conclusion
Individuals who are deprived are less likely to participate in screening, less likely to undergo colonoscopy and less likely to have cancer identified as a result of a positive test. Therefore, this study suggests that strategies aimed at improving participation of deprived individuals in colorectal cancer screening should be directed at all stages of the screening process and not just uptake of the test. 相似文献863.
864.
Oliver G. Bosch Michael Wagner Frank Jessen Kai-Uwe Kühn Alexius Joe Erich Seifritz Wolfgang Maier Hans-Jürgen Biersack Boris B. Quednow 《PloS one》2013,8(4)
Introduction
3,4-Methylenedioxymethamphetamine (MDMA, “ecstasy”) is a recreational club drug with supposed neurotoxic effects selectively on the serotonin system. MDMA users consistently exhibit memory dysfunction but there is an ongoing debate if these deficits are induced mainly by alterations in the prefrontal or mediotemporal cortex, especially the hippocampus. Thus, we investigated the relation of verbal memory deficits with alterations of regional cerebral brain glucose metabolism (rMRGlu) in recreational MDMA users.Methods
Brain glucose metabolism in rest was assessed using 2-deoxy-2-(18F)fluoro-D-glucose positron emission tomography (18FDG PET) in 19 male recreational users of MDMA and 19 male drug-naïve controls. 18FDG PET data were correlated with memory performance assessed with a German version of the Rey Auditory Verbal Learning Test.Results
As previously shown, MDMA users showed significant impairment in verbal declarative memory performance. PET scans revealed significantly decreased rMRGlu in the bilateral dorsolateral prefrontal and inferior parietal cortex, bilateral thalamus, right hippocampus, right precuneus, right cerebellum, and pons (at the level of raphe nuclei) of MDMA users. Among MDMA users, learning and recall were positively correlated with rMRGlu predominantly in bilateral frontal and parietal brain regions, while recognition was additionally related to rMRGlu in the right mediotemporal and bihemispheric lateral temporal cortex. Moreover, cumulative lifetime dose of MDMA was negatively correlated with rMRGlu in the left dorsolateral and bilateral orbital and medial PFC, left inferior parietal and right lateral temporal cortex.Conclusions
Verbal learning and recall deficits of recreational MDMA users are correlated with glucose hypometabolism in prefrontal and parietal cortex, while word recognition was additionally correlated with mediotemporal hypometabolism. We conclude that memory deficits of MDMA users arise from combined fronto-parieto-mediotemporal dysfunction. 相似文献865.
866.
Egg parasitoids of the exotic invasive brown marmorated stink bug, Halyomorpha halys (Stål), were investigated using lab-reared fresh (live) and frozen (killed) lab-reared sentinel egg masses deployed for 72h on foliage in three habitats—woods, orchard, and soybean field—in Maryland, USA, in summer 2014. Four native hymenopteran species, Telenomus podisi Ashmead (Scelionidae), Trissolcus euschisti (Ashmead) and Tr. brochymenae Ashmead (Scelionidae), and Anastatus reduvii (Howard) (Eupelmidae), developed and emerged from H. halys eggs. One exotic parasitoid, Trissolcus japonicus (Ashmead), emerged, providing the first known occurrence of this species in North America. Native parasitoids emerged from frozen eggs significantly more often than from fresh eggs (89.3% of egg masses and 98.1% of individual eggs), whereas the exotic Tr. japonicus did not show a similar difference, strongly suggesting adaptation to H. halys as a host by Tr. japonicus but not by the native species. Parasitoids were habitat-specific: all three Trissolcus species were significantly more likely to occur in the woods habitat, whereas Te. podisi was found exclusively in the soybean field. Further investigations are required to elucidate evolving host-parasitoid relationships, habitat specificity, and non-target effects of Tr. japonicus over the expanded range of H. halys in North America. 相似文献
867.
Ingrid C. Rulifson Ping Cao Li Miao David Kopecky Linda Huang Ryan D. White Kim Samayoa Jonitha Gardner Xiaosu Wu Kui Chen Trace Tsuruda Oliver Homann Helene Baribault Harvey Yamane Tim Carlson Jed Wiltzius Yang Li 《PloS one》2016,11(2)
Pancreatic amyloid formation by islet amyloid polypeptide (IAPP) is a hallmark pathological feature of type 2 diabetes. IAPP is stored in the secretory granules of pancreatic beta-cells and co-secreted with insulin to maintain glucose homeostasis. IAPP is innocuous under homeostatic conditions but imbalances in production or processing of IAPP may result in homodimer formation leading to the rapid production of cytotoxic oligomers and amyloid fibrils. The consequence is beta-cell dysfunction and the accumulation of proteinaceous plaques in and around pancreatic islets. Beta-site APP-cleaving enzyme 2, BACE2, is an aspartyl protease commonly associated with BACE1, a related homolog responsible for amyloid processing in the brain and strongly implicated in Alzheimer’s disease. Herein, we identify two distinct sites of the mature human IAPP sequence that are susceptible to BACE2-mediated proteolytic activity. The result of proteolysis is modulation of human IAPP fibrillation and human IAPP protein degradation. These results suggest a potential therapeutic role for BACE2 in type 2 diabetes-associated hyperamylinaemia. 相似文献
868.
Svetlana Stepanović Andrea Kosovac Oliver Krstić Jelena Jović Ivo Toševski 《Insect Science》2016,23(4):638-648
Genotyping of 2 well‐known weevil species from the genus Ceutorhynchus (Coleoptera: Curculionidae) distributed in west Palearctic, C. erysimi and C. contractus, revealed phenotype versus genotype inconsistencies in a set of 56 specimens (25 C. erysimi and 31 C. contractus) collected from 25 locations in Serbia and Montenegro. An analysis of the mitochondrial cytochrome oxidase subunit I gene (COI), widely used as a barcoding region, and a nuclear gene, elongation factor‐1α (EF‐1α), revealed stable genetic divergence among these species. The average uncorrected pairwise distances for the COI and EF‐1α genes were 3.8%, and 1.3%, respectively, indicating 2 genetically well‐segregated species. However, the genetic data were not congruent with the phenotypic characteristics of the studied specimens. In the first place, C. erysimi genotypes were attached to specimens with phenotypic characteristics of C. contractus. Species‐specific PCR‐RFLP assays for the barcoding gene COI were applied for the molecular identification of 101 additional specimens of both morphospecies (33 C. erysimi and 68 C. contractus) and were found to confirm this incongruity. The discrepancy between the genetic and morphological data raises the question of the accuracy of using a barcoding approach, as it may result in misleading conclusions about the taxonomic position of the studied organism. Additionally, the typological species concept shows considerable weakness when genetic data are not supported with phenotypic characteristics as in case of asymmetric introgression, which may cause certain problems, especially in applied studies such as biological control programs in which the biological properties of the studied organisms are the main focus. 相似文献
869.
870.
A proteomics approach to identifying key protein targets involved in VEGF inhibitor mediated attenuation of bleomycin‐induced pulmonary fibrosis
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Yogesh M. Kulkarni Sucharita Dutta Anand Krishnan V. Iyer Rajkumar Venkatadri Vivek Kaushik Vani Ramesh Clayton A. Wright Oliver John Semmes Juan S. Yakisich Neelam Azad 《Proteomics》2016,16(1):33-46
Idiopathic pulmonary fibrosis (IPF) is a progressive lung disease with a life expectancy of less than 5 years post diagnosis for most patients. Poor molecular characterization of IPF has led to insufficient understanding of the pathogenesis of the disease, resulting in lack of effective therapies. In this study, we have integrated a label‐free LC‐MS based approach with systems biology to identify signaling pathways and regulatory nodes within protein interaction networks that govern phenotypic changes that may lead to IPF. Ingenuity Pathway Analysis of proteins modulated in response to bleomycin treatment identified PI3K/Akt and Wnt signaling as the most significant profibrotic pathways. Similar analysis of proteins modulated in response to vascular endothelial growth factor (VEGF) inhibitor (CBO‐P11) treatment identified natural killer cell signaling and PTEN signaling as the most significant antifibrotic pathways. Mechanistic/mammalian target of rapamycin (mTOR) and extracellular signal‐regulated kinase (ERK) were identified to be key mediators of pro‐ and antifibrotic response, where bleomycin (BLM) treatment resulted in increased expression and VEGF inhibitor treatment attenuated expression of mTOR and ERK. Using a BLM mouse model of pulmonary fibrosis and VEGF inhibitor CBO‐P11 as a therapeutic measure, we identified a comprehensive set of signaling pathways and proteins that contribute to the pathogenesis of pulmonary fibrosis that can be targeted for therapy against this fatal disease. 相似文献