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DNA methylation at CpG dinucleotides is an important epigenetic regulator common to virtually all mammalian cell types, but recent evidence indicates that during early postnatal development neuronal genomes also accumulate uniquely high levels of two alternative forms of methylation, non-CpG methylation and hydroxymethylation. Here we discuss the distinct landscape of DNA methylation in neurons, how it is established, and how it might affect the binding and function of protein readers of DNA methylation. We review studies of one critical reader of DNA methylation in the brain, the Rett syndrome protein methyl CpG-binding protein 2 (MeCP2), and discuss how differential binding affinity of MeCP2 for non-CpG and hydroxymethylation may affect the function of this methyl-binding protein in the nervous system.  相似文献   
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目的 探讨在苯妥英钠(Phenytoin,PHT)促进大鼠牙周膜干细胞(Rat periodontal ligament stem cells,rPDLSCs)、大鼠骨髓间充质干细胞(Rat Bone Marrow Mesenchymal Stem Cells,rBMMSCs)黏附于牙骨质过程中,整合素α5β1(Integrin α5β1)起到的作用。方法 提取大鼠BMMSCs和PDLSCs,培养并纯化。通过细胞鉴定后,将获得的两种细胞各分为4组:40 mg/L PHT处理组、40 mg/L PHT+整合素α5抗体处理组、40 mg/L PHT+整合素β1抗体处理组、PBS处理组,每组细胞放入置有牙骨质片的96孔板处理4 h后,检测黏附于牙骨质片上的细胞量并做以比较。最后,利用qRT-PCR和Western blot检测40 mg/L PHT组与对照组细胞的整合素α5、β1亚基的mRNA与蛋白表达量。结果 40 mg/L PHT可促进rBMMSCs及rPDLSCs黏附于牙骨质片,加入整合素α5、β1抗体后,均明显抑制了40 mg/L PHT对rBMMSCs、rPDLSCs黏附于牙骨质的促进作用(P<0.01)。qRT-PCR、Western-blot结果显示PHT处理组的整合素α5、β1亚基表达量高于空白对照组(P<0.05)。结论 40 mg/L PHT能促进rBMMSCs、rPDLSCs黏附于牙骨质,该作用与整合素α5β1的表达上调密切相关。  相似文献   
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INTRODUCTION: There are no measures of health-related absenteeism and presenteeism validated for use in the large and increasing US Spanish-speaking population. Before using a Spanish translation of an available English-language questionnaire, the linguistic validity of the Spanish version must be established to ensure its conceptual equivalence to the original and its cultural appropriateness. OBJECTIVE: The objective of this study was to evaluate the linguistic validity of the US Spanish version of the Work Productivity and Activity Impairment questionnaire, General Health Version (WPAI:GH). METHODS: A US Spanish translation of the US English WPAI:GH was created through a reiterative process of creating harmonized forward and back translations by independent translators. Spanish-speaking and English-speaking subjects residing in the US self-administered the WPAI:GH in their primary language and were subsequently debriefed by a bilingual (Spanish-English) interviewer. RESULTS: US Spanish subjects (N = 31) and English subjects (N = 35), stratified equally by educational level, with and without a high school degree participated in the study. The WPAI-GH item comprehension rate was 98.6% for Spanish and 99.6% for English. Response revision rates during debriefing were 1.6% for Spanish and 0.5% for English. Responses to hypothetical scenarios indicated that both language versions adequately differentiate sick time taken for health and non-health reasons and between absenteeism and presenteeism. CONCLUSION: Linguistic validity of the US Spanish translation of the WPAI:GH was established among a diverse US Spanish-speaking population, including those with minimal education.  相似文献   
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Stuart Cathcart  BA    Donald Pritchard  PhD 《Headache》1998,38(3):214-221
An exploratory study was conducted examining arousal-related moods and episodic tension-type headache. Twelve subjects meeting International Headache Society criteria for episodic tension-type headache and 12 headache-free controls recorded headache activity and mood eight times daily for 14 consecutive days. Moods were measured using the Activation-Deactivation Adjective Check List, a self-report list that subjectively represents general arousal along two dimensions of Tension and Energy. Headache subjects had higher Tension levels than controls even in the absence of pain, and greater variation in this dimension as well. Within the headache group, Tension during pain-free periods was significantly lower than when experiencing headache, and was correlated with headache activity. The results were taken to support Thayer's (1989) biopsychological model of mood and arousal, and are discussed in terms of the model's heuristic value for general arousal and headache research.  相似文献   
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