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41.
Ecological experiments often require standardized methods that exclude natural variation and allow manipulation of a single parameter. It has been shown that domesticated honey bee larvae are raisable in a controlled environment. Here we demonstrate that this approach is also transferable to wild solitary bees and wasps without inducing negative effects on their development. Wells may also be supplemented with the antibiotic substance oxytetracycline to control the presence of bacteria. The method thus provides a useful tool to investigate offspring recruitment and larval development in solitary bees and wasps, plus their responses to manipulation of factors as for example diets, toxins and microbiota.  相似文献   
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Background:Use of electronic cigarettes (e-cigarettes) among adolescents has not been fully described, in particular their motivations for using them and factors associated with use. We sought to evaluate the frequency, motivations and associated factors for e-cigarette use among adolescents in Ontario.Methods:We conducted a cross-sectional study in the Niagara region of Ontario, Canada, involving universal screening of students enrolled in grade 9 in co-operation with the Heart Niagara Inc. Healthy Heart Schools’ Program (for the 2013–2014 school year). We used a questionnaire to assess cigarette, e-cigarette and other tobacco use, and self-rated health and stress. We assessed household income using 2011 Canadian census data by matching postal codes to census code.Results:Of 3312 respondents, 2367 answered at least 1 question in the smoking section of the questionnaire (1274 of the 2367 respondents [53.8%] were male, with a mean [SD] age of 14.6 [0.5] yr) and 2292 answered the question about use of e-cigarettes. Most respondents to the questions about use of e-cigarettes (n = 1599, 69.8%) had heard of e-cigarettes, and 380 (23.8%) of these respondents had learned about them from a store sign or display. Use of e-cigarettes was reported by 238 (10.4%) students. Most of the respondents who reported using e-cigarettes (171, 71.9%) tried them because it was “cool/fun/new,” whereas 14 (5.8%) reported using them for smoking reduction or cessation. Male sex, recent cigarette or other tobacco use, family members who smoke and friends who smoke were strongly associated with reported e-cigarette use. Reported use of e-cigarettes was associated with self-identified fair/poor health rating (odds ratio [OR] 1.9 (95% confidence interval [CI] 1.2–3.0), p < 0.001), high stress level (OR 1.7 (95% CI 1.1–2.7), p < 0.001) and lower mean (33.4 [8.4] × $1000 v. 36.1 [10.7] × $1000, p = 0.001) and median [interquartile range] (26.2 [5.6] × $1000 v. 28.1 [5.7] × $1000) household incomes.Interpretation:Use of e-cigarettes is common among adolescents in the Niagara region and is associated with sociodemographic features. Engaging in seemingly exciting new behaviours appears to be a key motivating factor rather than smoking cessation.Electronic cigarettes (e-cigarettes) are novel devices that are designed to mimic the physical and tactile experience of conventional cigarettes while producing a smoke-free vapour. They have quickly gained popularity despite limited evidence regarding the health risks associated with their use and a lack of regulation.1 In addition, existing literature about e-cigarettes suggests that they may not be effective for achieving smoking reduction or cessation, a use for which they are often marketed.13 Given their physical similarities to conventional cigarettes, there are concerns that the increasing use of e-cigarettes may result in the “renormalization” of cigarette smoking.4,5 Previous studies have suggested that use of e-cigarettes among adolescents and young adults may be associated with use of and exposure to tobacco.1,6,7Rates of the use of e-cigarettes at least once among high school students in the United States have increased annually.6,8 Among adolescents in Canada, use of e-cigarettes is now more common than cigarette use.9 However, questions still remain regarding the motivations and factors associated with e-cigarette use among adolescents. Therefore, we sought to evaluate the frequency, motivations and associated factors for use of e-cigarettes by students in grade 9 who were undergoing universal school-based screening for cardiovascular risk factors in the Niagara region in Ontario.  相似文献   
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In this work, an overview of the biosimilars market, pipeline and industry targets is discussed. Biosimilars typically have a shorter timeline for approval (8 years) compared to 12 years for innovator drugs and the development cost can be 10–20% of the innovator drug. The biosimilar pipeline is reviewed as well as the quality management system (QMS) that is needed to generate traceable, trackable data sets. One difference between developing a biosimilar compared to an originator is that a broader analytical foundation is required for biosimilars and advances made in developing analytical similarity to characterize these products are discussed. An example is presented on the decisions and considerations explored in the development of a biosimilar and includes identification of the best process parameters and methods based on cost, time, and titer. Finally factors to consider in the manufacture of a biosimilar and approaches used to achieve the target-directed development of a biosimilar are discussed.

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The pattern recognition receptor CD36 initiates a signaling cascade that promotes microglial activation and recruitment to beta-amyloid deposits in the brain. In the present study we identify the focal adhesion-associated proteins p130Cas, Pyk2, and paxillin as novel members of the tyrosine kinase signaling pathway downstream of CD36 and show that assembly of this complex is essential for microglial migration. In primary microglia and macrophages exposed to beta-amyloid, the scaffolding protein p130Cas is rapidly tyrosine-phosphorylated and co-localizes with CD36 to membrane ruffles contemporaneous with F-actin polymerization. These beta-amyloid-stimulated events are not detected in CD36 null cells and are dependent on CD36 activation of Src family tyrosine kinases. Fyn, a Src kinase known to interact with CD36, co-precipitates with p130Cas and is an essential upstream intermediate in the signaling pathways leading to phosphorylation of the p130Cas substrate domain. Furthermore, the p130Cas-interacting kinase Pyk2 and the cytoskeletal adapter protein paxillin also demonstrate CD36-dependent phosphorylation, identifying these focal adhesion molecules as additional members of this beta-amyloid signaling cascade. Disruption of this p130Cas complex by small interfering RNA silencing inhibits p44/42 mitogen-activated protein kinase phosphorylation and microglial migration, illustrating the importance of this pathway in microglial activation and recruitment. Together, these data are the first to identify the signaling cascade that directly links CD36 to the actin cytoskeleton and, thus, implicates it in diverse processes such as cellular migration, adhesion, and phagocytosis.  相似文献   
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Cardio/cerebrovascular diseases (CVD) have become one of the major health issue in our societies. But recent studies show that the present pathology tests to detect CVD are ineffectual as they do not consider different stages of platelet activation or the molecular dynamics involved in platelet interactions and are incapable to consider inter-individual variability. Here we propose a stochastic platelet deposition model and an inferential scheme to estimate the biologically meaningful model parameters using approximate Bayesian computation with a summary statistic that maximally discriminates between different types of patients. Inferred parameters from data collected on healthy volunteers and different patient types help us to identify specific biological parameters and hence biological reasoning behind the dysfunction for each type of patients. This work opens up an unprecedented opportunity of personalized pathology test for CVD detection and medical treatment.  相似文献   
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The androgen-independent human prostate adenocarcinoma cell line DU-145 proliferates in serum-free medium and produces insulin-like growth factors (IGF)-I, IGF-II, and the IGF type-1 receptor (IGF-1R). They also secrete three IGF-binding proteins (IGFBP), IGFBP-2, -3, and -4. Of these, immunoblot analysis revealed selective proteolysis of IGFBP-3, yielding fragments of 31 and 19 kDa. By using an anti-IGF-I-specific monoclonal antibody (mAb), we detect surface receptor-bound IGF-I on serum-starved DU-145 cells, which activates IGF-1R and triggers a mitogenic signal. Incubation of DU-145 cells with blocking anti-IGF-I, anti-IGF-II, or anti-IGF-I plus anti-IGF-II mAb does not, however, inhibit serum-free growth of DU-145. Conversely, anti-IGF-1R mAb and IGFBP-3 inhibit DNA synthesis. IGFBP-3 also modifies the DU-145 cell cycle, decreases p34(cdc2) levels, and IGF-1R autophosphorylation. The antiproliferative IGFBP-3 activity is not IGF-independent, since des-(1-3)IGF-I, which does not bind to IGFBP-3, reverses its inhibitory effect. DU-145 also secretes the matrix metalloproteinase (MMP)-9, which can be detected in both a soluble and a membrane-bound form. Matrix metalloproteinase inhibitors, but not serpins, abrogate DNA synthesis in DU-145 associated with the blocking of IGFBP-3 proteolysis. Overexpression of an antisense cDNA for MMP-9 inhibits 80% of DU-145 cell proliferation that can be reversed by IGF-I in a dose-dependent manner. Inhibition of MMP-9 expression is also associated with a decrease in IGFBP-3 proteolysis and with reduced signaling through the IGF-1R. Our data indicate an IGF autocrine loop operating in DU-145 cells, specifically modulated by IGFBP-3, whose activity may in turn be regulated by IGFBP-3 proteases such as MMP-9.  相似文献   
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