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211.
Sharmila Vaz Marita Falkmer Marina Ciccarelli Anne Passmore Richard Parsons Melissa Black Belinda Cuomo Tele Tan Torbj?rn Falkmer 《PloS one》2015,10(9)
It is unknown if, and how, students redefine their sense of school belongingness after negotiating the transition to secondary school. The current study used longitudinal data from 266 students with, and without, disabilities who negotiated the transition from 52 primary schools to 152 secondary schools. The study presents the 13 most significant personal student and contextual factors associated with belongingness in the first year of secondary school. Student perception of school belongingness was found to be stable across the transition. No variability in school belongingness due to gender, disability or household-socio-economic status (SES) was noted. Primary school belongingness accounted for 22% of the variability in secondary school belongingness. Several personal student factors (competence, coping skills) and school factors (low-level classroom task-goal orientation), which influenced belongingness in primary school, continued to influence belongingness in secondary school. In secondary school, effort-goal orientation of the student and perception of their school’s tolerance to disability were each associated with perception of school belongingness. Family factors did not influence belongingness in secondary school. Findings of the current study highlight the need for primary schools to foster belongingness among their students at an early age, and transfer students’ belongingness profiles as part of the hand-over documentation. Most of the factors that influenced school belongingness before and after the transition to secondary are amenable to change. 相似文献
212.
Daria A. Gaykalova Rajita Vatapalli Yingying Wei Hua-Ling Tsai Hao Wang Chi Zhang Patrick T. Hennessey Theresa Guo Marietta Tan Ryan Li Julie Ahn Zubair Khan William H. Westra Justin A. Bishop David Zaboli Wayne M. Koch Tanbir Khan Michael F. Ochs Joseph A. Califano 《PloS one》2015,10(11)
Head and Neck Squamous Cell Carcinoma (HNSCC) is the fifth most common cancer, annually affecting over half a million people worldwide. Presently, there are no accepted biomarkers for clinical detection and surveillance of HNSCC. In this work, a comprehensive genome-wide analysis of epigenetic alterations in primary HNSCC tumors was employed in conjunction with cancer-specific outlier statistics to define novel biomarker genes which are differentially methylated in HNSCC. The 37 identified biomarker candidates were top-scoring outlier genes with prominent differential methylation in tumors, but with no signal in normal tissues. These putative candidates were validated in independent HNSCC cohorts from our institution and TCGA (The Cancer Genome Atlas). Using the top candidates, ZNF14, ZNF160, and ZNF420, an assay was developed for detection of HNSCC cancer in primary tissue and saliva samples with 100% specificity when compared to normal control samples. Given the high detection specificity, the analysis of ZNF DNA methylation in combination with other DNA methylation biomarkers may be useful in the clinical setting for HNSCC detection and surveillance, particularly in high-risk patients. Several additional candidates identified through this work can be further investigated toward future development of a multi-gene panel of biomarkers for the surveillance and detection of HNSCC. 相似文献
213.
Youichi Suzuki Wei-Xin Chin Qi'En Han Koji Ichiyama Ching Hua Lee Zhi Wen Eyo Hirotaka Ebina Hirotaka Takahashi Chikako Takahashi Beng Hui Tan Takayuki Hishiki Kenji Ohba Toshifumi Matsuyama Yoshio Koyanagi Yee-Joo Tan Tatsuya Sawasaki Justin Jang Hann Chu Subhash G. Vasudevan Kouichi Sano Naoki Yamamoto 《PLoS pathogens》2016,12(1)
Dengue virus (DENV) is one of the most important arthropod-borne pathogens that cause life-threatening diseases in humans. However, no vaccine or specific antiviral is available for dengue. As seen in other RNA viruses, the innate immune system plays a key role in controlling DENV infection and disease outcome. Although the interferon (IFN) response, which is central to host protective immunity, has been reported to limit DENV replication, the molecular details of how DENV infection is modulated by IFN treatment are elusive. In this study, by employing a gain-of-function screen using a type I IFN-treated cell-derived cDNA library, we identified a previously uncharacterized gene, C19orf66, as an IFN-stimulated gene (ISG) that inhibits DENV replication, which we named Repressor of yield of DENV (RyDEN). Overexpression and gene knockdown experiments revealed that expression of RyDEN confers resistance to all serotypes of DENV in human cells. RyDEN expression also limited the replication of hepatitis C virus, Kunjin virus, Chikungunya virus, herpes simplex virus type 1, and human adenovirus. Importantly, RyDEN was considered to be a crucial effector molecule in the IFN-mediated anti-DENV response. When affinity purification-mass spectrometry analysis was performed, RyDEN was revealed to form a complex with cellular mRNA-binding proteins, poly(A)-binding protein cytoplasmic 1 (PABPC1), and La motif-related protein 1 (LARP1). Interestingly, PABPC1 and LARP1 were found to be positive modulators of DENV replication. Since RyDEN influenced intracellular events on DENV replication and, suppression of protein synthesis from DENV-based reporter construct RNA was also observed in RyDEN-expressing cells, our data suggest that RyDEN is likely to interfere with the translation of DENV via interaction with viral RNA and cellular mRNA-binding proteins, resulting in the inhibition of virus replication in infected cells. 相似文献
214.
Junjun Tan Shibin He Shihan Yan Yingnan Li Hui Li Hao Zhang Lin Zhao Lijia Li 《Protoplasma》2014,251(5):1213-1221
Copper is a micronutrient required for living organisms, but is potentially toxic in excess. EDDS enhances the phytoextraction of many metals, but the underlying mechanism is fully unclear. Exposure of 200 μM Cu2+ for 3 days resulted in rice seedling growth inhibition, accompanied by a decrease in plasma membrane H+-ATPase activity, and an increase in relative electrolyte leakage ratios, indicating that maintaining of membrane structure integrity is crucial in acclimation of plants to heavy metal stress. In addition, the chlorophyll and carotenoid content was markedly decreased and the level of the mRNA of Cytochrome P450 gene, OsHMA9, the sulfate transporter gene, and the metallothionein-like protein gene was observed to increase in response to Cu stress. Cu treatment also induced a global epigenetic response which is associated with cell nucleus condensation. These physiological, genetic, and epigenetic responses of rice seedlings to excess copper were modified by the addition of EDDS, suggesting that the supply of EDDS in medium containing a high concentration of Cu ions could enhance plant tolerance potential to excess Cu toxicity through alleviating Cu-induced poisonous effects at various levels. 相似文献
215.
利用生物测定和生物化学方法研究了抗药性棉铃虫Helicoverpa armigera(Hubner)对拟除虫菊酯敏感性修复及其体内乙酰胆碱酯酶的变化,结果表明:当去除药剂选择压后,棉铃虫对拟除虫菊酯的抗性为不稳定。随着停止用药的时间加长,敏感性增加。从田间收集的棉铃虫在室内饲养后第1代对拟除虫菊酯的抗性下降速度较迅速。特异性酶抑制剂对敏感和抗性棉铃虫种群的乙酰胆碱酯酶亲和力试验结果证实,乙酰胆碱酯酶在抗性棉铃虫对杀虫剂反应发生变化的过程中发生改变,这种酶的改变可能对棉铃虫抗药性的不稳定性有重要影响。 相似文献
216.
Investigation on recombinant hirudin via oral route 总被引:2,自引:0,他引:2
The possibility for oral administration of peptide recombinant hirudin variant (rHV2-K47) as an anticoagulant agent was evaluated in several aspects. The proteolytic properties of rHV2-K47 and its stability during storage were examined by in vitro experiments. Radiolabeled rHV2-K47 was infused into the duodenum of rats and rHV2-K47 absorbed into serum was shown to be intact by electrophoresis pattern. The in vivo coagulation time of blood from mouse was prolonged significantly after oral administration of rHV2-K47. The bioavailability (F) of rHV2-K47 via oral route reached 10.11% in comparison with intravenous administration as gold standard. All the results suggested that rHV2-K47 could be delivered successfully via the oral route. 相似文献
217.
Tan Q Christiansen L Bathum L Zhao JH Yashin AI Vaupel JW Christensen K Kruse TA 《Human heredity》2005,59(2):88-97
Association-based linkage disequilibrium (LD) mapping is an increasingly important tool for localizing genes that show potential influence on human aging and longevity. As haplotypes contain more LD information than single markers, a haplotype-based LD approach can have increased power in detecting associations as well as increased robustness in statistical testing. In this paper, we develop a new statistical model to estimate haplotype relative risks (HRRs) on human survival using unphased multilocus genotype data from unrelated individuals in cross-sectional studies. Based on the proportional hazard assumption, the model can estimate haplotype risk and frequency parameters, incorporate observed covariates, assess interactions between haplotypes and the covariates, and investigate the modes of gene function. By introducing population survival information available from population statistics, we are able to develop a procedure that carries out the parameter estimation using a nonparametric baseline hazard function and estimates sex-specific HRRs to infer gene-sex interaction. We also evaluate the haplotype effects on human survival while taking into account individual heterogeneity in the unobserved genetic and nongenetic factors or frailty by introducing the gamma-distributed frailty into the survival function. After model validation by computer simulation, we apply our method to an empirical data set to measure haplotype effects on human survival and to estimate haplotype frequencies at birth and over the observed ages. Results from both simulation and model application indicate that our survival analysis model is an efficient method for inferring haplotype effects on human survival in population-based association studies. 相似文献
218.
The effects of proteasome inhibitor lactacystin on mouse oocyte meiosis and first cleavage 总被引:1,自引:0,他引:1
TAN Xin PENG An WANG Yongchao & TANG Zuoqing . School of Life Sciences Technology Beijing Institute of Technology Beijing China . College of Life Sciences Beijing Normal University Beijing China . College of Basic Medicine Capital University of Medical Sciences Beijing China 《中国科学:生命科学英文版》2005,48(3):287-294
Many studies have shown that the ubiq-uitin-proteasome pathway (UPP) for the degradation of short-lived proteins plays a key role in regulating cell cycle progression[1—3]. At least two distinct prote-olytic pathways are required for cell cycle process. The first pathway promotes transition from G1 to S phase, and the second initiates the onset of anaphase and exit from mitosis. The inhibition of UPP will re-sult in the blockage of cell cycle process. The knowl-edge of the role of UPP in… 相似文献
219.
This paper proposes an ensemble of classifiers for biomedical name recognition in which three classifiers, one Support Vector Machine and two discriminative Hidden Markov Models, are combined effectively using a simple majority voting strategy. In addition, we incorporate three post-processing modules, including an abbreviation resolution module, a protein/gene name refinement module and a simple dictionary matching module, into the system to further improve the performance. Evaluation shows that our system achieves the best performance from among 10 systems with a balanced F-measure of 82.58 on the closed evaluation of the BioCreative protein/gene name recognition task (Task 1A). 相似文献
220.
Tan G Pan S Li J Dong X Kang K Zhao M Jiang X Kanwar JR Qiao H Jiang H Sun X 《PloS one》2011,6(10):e25943