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31.
Zitta B. Harboe Palle Valentiner-Branth Helene Ingels Jeppe N. Rasmussen Peter H. S. Andersen Catherine C. Bjerre David Goldblatt Lindsey Ashton Mitch Haston Helle B. Konradsen Lotte Lambertsen 《PloS one》2013,8(1)
A seven-valent pneumococcal conjugate vaccine (PCV7) was introduced in the Danish childhood immunization program (2+1 schedule) in October 2007, followed by PCV13 starting from April 2010. The nationwide incidence of IPD among children younger than 5 years nearly halved after the introduction of PCV7 in the program, mainly due to a decline in IPD caused by PCV7-serotypes. We report the results from a nationwide population-based cohort study of laboratory confirmed IPD cases in children younger than 5 years during October 1, 2007 to December 31, 2010 and describe the characteristics of children suspected to present with a vaccine failure. The period between April 19 and December 31, 2010 was considered a PCV7/PCV13 transitional period, where both vaccines were offered. We identified 45 episodes of IPD caused by a PCV7 serotype (23% of the total number) and 105 (55%) caused by one of the 6 additional serotypes in PCV13. Ten children had received at least one PCV7 dose before the onset of IPD caused by a PCV7 serotype. Seven children were considered to be incompletely vaccinated before IPD, but only three cases fulfilled the criteria of vaccine failure (caused by serotypes 14, 19F and 23F). One case of vaccine failure was observed in a severely immunosuppressed child following three PCV7 doses, and two cases were observed in immunocompetent children following two infant doses before they were eligible for their booster. None of the IPD cases caused by the additional PCV13 serotypes had been vaccinated by PCV13 and there were therefore no PCV13-vaccine failures in the first 8-months after PCV13 introduction in Denmark. 相似文献
32.
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
33.
Quentin J. M. Huys Daniel Renz Frederike Petzschner Isabel Berwian Christian Stoppel Helene Haker 《PloS one》2016,11(3)
Background
The Cognitive Style Questionnaire is a valuable tool for the assessment of hopeless cognitive styles in depression research, with predictive power in longitudinal studies. However, it is very burdensome to administer. Even the short form is still long, and neither this nor the original version exist in validated German translations.Methods
The questionnaire was translated from English to German, back-translated and commented on by clinicians. The reliability, factor structure and external validity of an online form of the questionnaire were examined on 214 participants. External validity was measured on a subset of 90 subjects.Results
The resulting CSQ-SF-D had good to excellent reliability, both across items and subscales, and similar external validity to the original English version. The internality subscale appeared less robust than other subscales. A detailed analysis of individual item performance suggests that stable results could be achieved with a very short form (CSQ-VSF-D) including only 27 of the 72 items.Conclusions
The CSQ-SF-D is a validated and freely distributed translation of the CSQ-SF into German. This should make efficient assessment of cognitive style in German samples more accessible to researchers. 相似文献34.
Using simulations to evaluate Mantel‐based methods for assessing landscape resistance to gene flow
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Katherine A. Zeller Tyler G. Creech Katie L. Millette Rachel S. Crowhurst Robert A. Long Helene H. Wagner Niko Balkenhol Erin L. Landguth 《Ecology and evolution》2016,6(12):4115-4128
Mantel‐based tests have been the primary analytical methods for understanding how landscape features influence observed spatial genetic structure. Simulation studies examining Mantel‐based approaches have highlighted major challenges associated with the use of such tests and fueled debate on when the Mantel test is appropriate for landscape genetics studies. We aim to provide some clarity in this debate using spatially explicit, individual‐based, genetic simulations to examine the effects of the following on the performance of Mantel‐based methods: (1) landscape configuration, (2) spatial genetic nonequilibrium, (3) nonlinear relationships between genetic and cost distances, and (4) correlation among cost distances derived from competing resistance models. Under most conditions, Mantel‐based methods performed poorly. Causal modeling identified the true model only 22% of the time. Using relative support and simple Mantel r values boosted performance to approximately 50%. Across all methods, performance increased when landscapes were more fragmented, spatial genetic equilibrium was reached, and the relationship between cost distance and genetic distance was linearized. Performance depended on cost distance correlations among resistance models rather than cell‐wise resistance correlations. Given these results, we suggest that the use of Mantel tests with linearized relationships is appropriate for discriminating among resistance models that have cost distance correlations <0.85 with each other for causal modeling, or <0.95 for relative support or simple Mantel r. Because most alternative parameterizations of resistance for the same landscape variable will result in highly correlated cost distances, the use of Mantel test‐based methods to fine‐tune resistance values will often not be effective. 相似文献
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37.
Tree diversity,tree height and environmental harshness in eastern and western North America
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Does variation in environmental harshness explain local and regional species diversity gradients? We hypothesise that for a given life form like trees, greater harshness leads to a smaller range of traits that are viable and thereby also to lower species diversity. On the basis of a strong dependence of maximum tree height on site productivity and other measures of site quality, we propose maximum tree height as an inverse measure of environmental harshness for trees. Our results show that tree species richness is strongly positively correlated with maximum tree height across multiple spatial scales in forests of both eastern and western North America. Maximum tree height co‐varied with species richness along gradients from benign to harsh environmental conditions, which supports the hypothesis that harshness may be a general mechanism limiting local diversity and explaining diversity gradients within a biogeographic region. 相似文献
38.
Prolonged endoplasmic reticulum (ER) stress reduces protein synthesis and induces apoptosis in mammalian cells. When dimethyl sulfoxide (DMSO), a specific monoclonal antibody productivity (qmAb)‐enhancing reagent, is added to recombinant Chinese hamster ovary (rCHO) cell cultures (GSR cell line), it induces ER stress and apoptosis in a dose‐dependent manner. To determine an effective ER stress inhibitor, three ER stress inhibitors (BiP inducer X [BIX], tauroursodeoxycholic acid, and carbazole) are examined and BIX shows the best production performance. Coaddition of BIX (50 μm ) with DMSO extends the culture longevity and enhances qmAb. As a result, the maximum mAb concentration is significantly increased with improved galactosylation. Coaddition of BIX significantly increases the expression level of binding immunoglobulin protein (BiP) followed by increased expression of chaperones (calnexin and GRP94) and galactosyltransferase. Furthermore, the expression levels of CHOP, a well‐known ER stress marker, and cleaved caspase‐3 are significantly reduced, suggesting that BIX addition reduces ER stress‐induced cell death by relieving ER stress. The beneficial effect of BIX on mAb production is also demonstrated with another qmAb‐enhancing reagent (sodium butyrate) and a different rCHO cell line (CS13‐1.00). Taken together, BIX is an effective ER stress inhibitor that can be used to increase mAb production in rCHO cells. 相似文献
39.
Jos C. E. Serrano Juan Antonio Baena‐Fustegueras Meritxell Martin‐Gari Helene Rassendren Anna Cassanye Alba Naudí Carolina Lpez‐Cano Enric Snchez María Cruz de la Fuente‐Jurez Fernando Herrerías Gonzlez Jorge J. Olsina Kissler Albert Lecube Manuel Portero‐Otín 《Obesity (Silver Spring, Md.)》2019,27(7):1133-1140
40.
The Cbl- and ubiquitin-interacting protein T-cell ubiquitin ligand (TULA) has been demonstrated to inhibit endocytosis and downregulation of ligand-activated EGF receptor (EGFR) by impairing Cbl-induced ubiquitination. We presently report that TULA additionally inhibited clathrin-dependent endocytosis in general, as both uptake of transferrin (Tf) and low-density lipoprotein (LDL) was inhibited. Additionally, endocytosis of the raft proteins CD59 and major histocompatibility complex class I (MHC-I), which we demonstrate were mainly endocytosed clathrin-independently, but dynamin-dependently, was blocked in cells overexpressing TULA. By contrast, the uptake of ricin, which is mainly endocytosed clathrin- and dynamin-independently, was not affected by overexpressed TULA. Consistently, TULA and dynamin co-immunoprecipitated and colocalized intracellularly, and upon overexpression of dynamin the TULA-mediated inhibitory effect on endocytosis of Tf, LDL, CD59 and MHC-I was counteracted. Overexpressed dynamin did not restore ubiquitination of the EGFR, and consistently dynamin did not rescue endocytosis of the EGFR in cells overexpressing TULA. We conclude that TULA inhibits both clathrin-dependent and clathrin-independent endocytic pathways by functionally sequestering dynamin via the SH3 domain of TULA binding proline-rich sequences in dynamin. 相似文献