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目的:探讨蜂胶黄酮短叶松素-3-乙酸酯(pinobanksin-3-acetate,PB3A)对结肠癌SW480细胞微小RNA(microRNA,miRNA)表达谱的影响,为结肠癌的治疗及靶向药物研发提供理论依据。方法:使用miRNA芯片技术分析检测蜂胶黄酮PB3A处理人类结肠癌SW480细胞后miRNA表达谱的变化。通过实时荧光定量PCR方法检测miRNA-198和miRNA-296-5p的表达水平,以此来验证miRNA芯片结果的准确性和可靠性。利用miRWalk、Micro T、miRanda等12个网上数据库预测这2条miRNAs的靶基因并进行靶基因功能富集分析。结果:miRNA芯片分析结果显示,蜂胶黄酮PB3A干预24 h后结肠癌SW480细胞中差异表达倍数在2倍及以上的miRNA有267条,其中差异表达倍数达10倍及以上的miRNA有30条,28条为上调表达,2条下调表达;RT-qPCR实验结果显示miRNA-198和miRNA-296-5p的表达量趋势跟miRNA芯片结果一致,表达差异有统计学意义(P0.05)。miRNA靶基因预测发现miRNA-198有859个靶基因,miRNA-296-5p有906个靶基因;对这些可能被调控的靶基因进行Gene Class分析,结果显示miRNA-198和miRNA-296-5p的靶基因功能主要为转录因子、拷贝数变异、细胞分化、癌基因、蛋白激酶、组蛋白、转移癌基因、肿瘤抑制基因等(P0.05)。信号通路富集分析结果显示,miRNA-198靶基因显著富集于肿瘤通路、Wnt信号通路、胞吞通路、Erb B信号通路、黏着斑通路、黑素生成通路等信号通路,而miRNA-296-5p靶基因在MAPK信号通路、胞吞通路、轴突导向通路、Wnt信号通路、胰岛素信号通路、钙离子信号通路等信号通路中出现聚集(P0.05)。结论:蜂胶黄酮PB3A影响结肠癌SW480细胞的miRNA表达谱。PB3A作用下miRNA-198和miRNA-296-5p的异常表达可能参与PB3A抗结肠癌的过程。  相似文献   
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Metabolic Brain Disease - Nonketotic hyperglycinemia is an autosomal recessive inborn error of glycine metabolism, characterized by deficient activity of the glycine cleavage enzyme system. Classic...  相似文献   
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The study investigated growth, dietary intake and the feeding behaviors of children with cerebral palsy (CP) who could not manage chewable food textures. The study included 2 groups: a study group of children with CP whose diet did not consist of chewable foods, and a control group of typically developing children, who consumed all food. The International Dysphagia Diet Standardisation Initiative (IDDSI) was used during group allocation. Dietary assessment was performed using the 24-hour diet recall method; food type, amount ingested, and texture were considered to determine the IDDSI levels. The z-scores of nutritional indicators were calculated and a parent report instrument, the Behavioural Paediatrics Feeding Assessment Scale (BPFAS), was used to assess feeding behaviors. Eighty-five children were included. There was no differences between groups in terms of age (p=0.16) and sex (p=0.73). The mean weight (p=0.002) and height (p=0.011) for age Z-scores of study group were lower. Also in the study group, daily calorie and fat intakes were lower (p=0.038,p=0.011;respectively), whereas water from food and calcium intakes were higher (p=0.001,p<0.001,respectively). Feeding problems were determined in 48% of study group, whereas in 5.7% of the control group (p<0.001). Parents in the study group reported higher stress levels and more concerns about the child’s feeding behavior (p<0.001). Children with CP have deficits in their obtainment of the necessary nutrition and hydration. The inability to intake any chewable food may contribute to these problems, and also cause negative feeding behaviors, and more problematic perceptions by parents. Clinical Trial Registration Number: NCT02777645.  相似文献   
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Nonalcoholic fatty liver disease (NAFLD) is characterized by hepatic steatosis in the absence of a history of significant alcohol use or other known liver disease. Nonalcoholic steatohepatitis (NASH) is the progressive form of NAFLD. The Pathology Committee of the NASH Clinical Research Network designed and validated a histological feature scoring system that addresses the full spectrum of lesions of NAFLD and proposed a NAFLD activity score (NAS) for use in clinical trials. The scoring system comprised 14 histological features, 4 of which were evaluated semi-quantitatively: steatosis (0-3), lobular inflammation (0-2), hepatocellular ballooning (0-2), and fibrosis (0-4). Another nine features were recorded as present or absent. An anonymized study set of 50 cases (32 from adult hepatology services, 18 from pediatric hepatology services) was assembled, coded, and circulated. For the validation study, agreement on scoring and a diagnostic categorization ("NASH," "borderline," or "not NASH") were evaluated by using weighted kappa statistics. Inter-rater agreement on adult cases was: 0.84 for fibrosis, 0.79 for steatosis, 0.56 for injury, and 0.45 for lobular inflammation. Agreement on diagnostic category was 0.61. Using multiple logistic regression, five features were independently associated with the diagnosis of NASH in adult biopsies: steatosis (P = .009), hepatocellular ballooning (P = .0001), lobular inflammation (P = .0001), fibrosis (P = .0001), and the absence of lipogranulomas (P = .001). The proposed NAS is the unweighted sum of steatosis, lobular inflammation, and hepatocellular ballooning scores. In conclusion, we present a strong scoring system and NAS for NAFLD and NASH with reasonable inter-rater reproducibility that should be useful for studies of both adults and children with any degree of NAFLD. NAS of > or =5 correlated with a diagnosis of NASH, and biopsies with scores of less than 3 were diagnosed as "not NASH."  相似文献   
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Read-across has generated much attention, since it may be used as an alternative approach for addressing the information requirements under REACH. Experience in the application of “read-across” has undoubtedly been gained within the context of the 2010 registrations (>1000 tonnes/annum). Industry, European Chemicals Agency (ECHA) and EU Member States all conceptually accept read-across approaches but difficulties still remain in applying them consistently in practice. A workshop on the ‘Use of Read-Across for Chemical Safety Assessment under REACH’, organised by ECHA with the active support of Cefic LRI was held on the 3rd October 2012 to gain insight on how ECHA evaluates read-across justifications, to share Industry experiences with read-across approaches and to discuss practical strategies to help develop scientifically valid read-across for future submissions.  相似文献   
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