目的应用生物信息学方法筛选出经尸体检验确诊的婴儿猝死综合征(sudden infant death syndrome,SIDS)和婴儿感染性猝死(infectious sudden death in infancy,ISDI)死者脑、心脏和肝组织中共有的差异表达mRNA,探讨SIDS与ISDI的共有分子...目的应用生物信息学方法筛选出经尸体检验确诊的婴儿猝死综合征(sudden infant death syndrome,SIDS)和婴儿感染性猝死(infectious sudden death in infancy,ISDI)死者脑、心脏和肝组织中共有的差异表达mRNA,探讨SIDS与ISDI的共有分子标记和发生机制。方法下载GSE70422、GSE136992数据集,用R软件limma包筛选SIDS和ISDI死者不同组织样本中差异表达的mRNA,进行重叠分析,并用R软件clusterProfiler包进行基因本体论(gene ontology,GO)和京都基因和基因组数据库(Kyoto Encyclopedia of Genes and Genomes,KEGG)富集分析,使用STRING数据库构建蛋白质-蛋白质相互作用(protein-protein interaction,PPI)网络,基于cytoHubba插件筛选hub基因。结果与数据集中的对照组相比,SIDS和ISDI死者组织样本中有19个显著的共同差异基因,其中心脏组织中16个、肝组织中3个,心脏组织星形肌动蛋白1(astrotactin 1,ASTN1)基因表达差异最显著。PPI网络确定了Ras同源基因家族成员A(ras homolog family member A,RHOA)、整合素亚单位α1(integrin subunit alpha 1,ITGA1)和H2B簇状组蛋白5(H2B clustered histone 5,H2BC5)是hub基因。GO和KEGG分析结果表明,共同差异基因富集在肌动蛋白细胞骨架的调节、黏着斑及对霉酚酸的反应等分子通路中。结论ASTN1、RHOA和ITGA1可能参与SIDS与ISDI的发生发展。共同差异基因富集在免疫与炎症反应相关通路中,说明SIDS与ISDI在免疫与炎症反应方面可能存在共同的分子调控机制。这些发现有望为SIDS与ISDI的分子解剖和法医学鉴定提供新的生物标记。展开更多
Finite element(FEM)analysis was used to systematically evaluate the inhomogeneity of deformation in cylindrical samples with various sample-anvil friction coefficients,m.It was found that the level of friction strongl...Finite element(FEM)analysis was used to systematically evaluate the inhomogeneity of deformation in cylindrical samples with various sample-anvil friction coefficients,m.It was found that the level of friction strongly influences the deformation homogeneity,which increases significantly with the friction coefficient although the overall geometry of the samples almost remains the same when m >0.4.The position,at which the effective strain along the maximum radial direction in a compressed sample is equal to the equivalent strain of the sample,does not vary greatly with respect to both equivalent strain of the sample and m.Hardness measurements of compressed cylindrical 5056B Al alloy samples revealed a change of effective strain distribution similar to that revealed by FEM analysis.There exists a quantitative relationship between the hardness and the effective strain if no recrystallization or recovery occurs during the compression process.展开更多
文摘目的应用生物信息学方法筛选出经尸体检验确诊的婴儿猝死综合征(sudden infant death syndrome,SIDS)和婴儿感染性猝死(infectious sudden death in infancy,ISDI)死者脑、心脏和肝组织中共有的差异表达mRNA,探讨SIDS与ISDI的共有分子标记和发生机制。方法下载GSE70422、GSE136992数据集,用R软件limma包筛选SIDS和ISDI死者不同组织样本中差异表达的mRNA,进行重叠分析,并用R软件clusterProfiler包进行基因本体论(gene ontology,GO)和京都基因和基因组数据库(Kyoto Encyclopedia of Genes and Genomes,KEGG)富集分析,使用STRING数据库构建蛋白质-蛋白质相互作用(protein-protein interaction,PPI)网络,基于cytoHubba插件筛选hub基因。结果与数据集中的对照组相比,SIDS和ISDI死者组织样本中有19个显著的共同差异基因,其中心脏组织中16个、肝组织中3个,心脏组织星形肌动蛋白1(astrotactin 1,ASTN1)基因表达差异最显著。PPI网络确定了Ras同源基因家族成员A(ras homolog family member A,RHOA)、整合素亚单位α1(integrin subunit alpha 1,ITGA1)和H2B簇状组蛋白5(H2B clustered histone 5,H2BC5)是hub基因。GO和KEGG分析结果表明,共同差异基因富集在肌动蛋白细胞骨架的调节、黏着斑及对霉酚酸的反应等分子通路中。结论ASTN1、RHOA和ITGA1可能参与SIDS与ISDI的发生发展。共同差异基因富集在免疫与炎症反应相关通路中,说明SIDS与ISDI在免疫与炎症反应方面可能存在共同的分子调控机制。这些发现有望为SIDS与ISDI的分子解剖和法医学鉴定提供新的生物标记。
基金Project(2016JJ1016) supported by the Science Fund for Distinguished Young Scholars of Hunan Province,ChinaProject(201301G0105337290) supported by the Program of Innovation and Entrepreneur Team Introduced by Guangdong Province,China
文摘Finite element(FEM)analysis was used to systematically evaluate the inhomogeneity of deformation in cylindrical samples with various sample-anvil friction coefficients,m.It was found that the level of friction strongly influences the deformation homogeneity,which increases significantly with the friction coefficient although the overall geometry of the samples almost remains the same when m >0.4.The position,at which the effective strain along the maximum radial direction in a compressed sample is equal to the equivalent strain of the sample,does not vary greatly with respect to both equivalent strain of the sample and m.Hardness measurements of compressed cylindrical 5056B Al alloy samples revealed a change of effective strain distribution similar to that revealed by FEM analysis.There exists a quantitative relationship between the hardness and the effective strain if no recrystallization or recovery occurs during the compression process.
