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991.
目的利用生物信息学筛选库欣综合征(CS)的核心基因及通路,并预测其相互作用的微小核糖核酸(miRNA)及小分子药物。 方法从GEO数据库下载CS基因芯片数据集并筛选出差异表达基因(DEG),随后对差异基因进行功能富集分析、蛋白互作分析、核心基因筛选,预测互作miRNA及小分子药物并进行验证。 结果共筛选出10个核心基因并预测出479个互作miRNA,相关通路集中在PI3K-Akt、cAMP、CS及MAPK信号通路等,奥那司匹、拉帕替尼是较为显著的小分子药物。 结论利用生物信息学方法筛选出参与CS发生发展的前5条信号通路、10个核心基因及479个互作miRNA,并预测出奥那司匹、拉帕替尼等小分子药物。  相似文献   
992.
993.
 位于一些基因3'端非翻译区的富含A、U元件(AREs)是目前公认的能够在转录后水平调节mRNA稳定性的元素之一。它兼具介导相关因子mRNA衰变及增强某些mRNA稳定性的作用,ARE结合蛋白及p38 MAPK信号转导通路在此过程中作用关键,miRNA与其也具有密切联系。  相似文献   
994.
目的:通过对癌症基因组图谱(The Cancer Genome Atlas,TCGA)数据库中的乳腺癌数据进行综合分析,寻找在乳腺癌中差异表达的长链非编码RNA(long non-coding RNA,lncRNA)、微小RNA(microRNA,miRNA)和信使RNA(messenger RNA,mRNA),构建乳腺癌竞争内源性RNA(competing endogenous RNA,ceRNA)网络,识别和预测ceRNA网络在乳腺癌中的作用。方法:下载TCGA数据库中乳腺癌组织样本基因表达谱数据,寻找差异表达的lncRNA、miRNA和mRNA,通过miRcode、miRTarBase、TargetScan和miRDB四个数据库对差异表达的RNA之间的关系进行分析,构建以上调和下调的miRNA为中心的ceRNA网络。采用Kaplan-Meier法分析乳腺癌ceRNA网络中的lncRNA、miRNA和mRNA表达量与患者生存预后的关系,采用基因富集分析法对乳腺癌ceRNA网络中mRNA基因功能和调控通路进行分析。结果:在乳腺癌中异常表达的350个lncRNA、185个miRNA和2 928个mRNA中,分别有23个lncRNA、27个miRNA、70个mRNA参与构建乳腺癌的ceRNA网络。Kaplan-Meier生存分析显示,lncRNA MAGI2-AS3(P=0.01)、GRIK1-AS1(P=0.03)以及miRNA hsa-miR-301b(P=0.01)、hsa-miR-503(P=0.04)和mRNA CCNE1(P=0.01)、KPNA2(P=0.02)、FLI1(P=0.02)、TGFBR2(P=0.02)这8个基因与乳腺癌患者的生存预后显著相关。70个mRNA主要被富集到20条通路上,其中有15条通路与肿瘤有关,最显著的通路为“Pathways in cancer”。结论:ceRNA网络在乳腺癌中发挥着重要的作用,多种差异表达基因与乳腺癌预后相关,可能成为潜在的肿瘤诊断标志物和治疗靶点。  相似文献   
995.
Vitiligo is a common depigmentary skin disease that may follow a pattern of multifactorial inheritance. The essential factors of its immunopathogenesis is thought to be the selective destruction of melanocytes. As a new class of microregulators of gene expression, miRNA have been reported to play vital roles in autoimmune diseases, metabolic diseases and cancer. This study sought to characterize the different miRNA expression pattern in the peripheral blood mononuclear cells (PBMC) of patients with non‐segmental vitiligo (NSV) and healthy individuals and to examine their direct responses to thymosin α1 (Tα1) treatment. The miRNA expression profile in the PBMC of patients with NSV was analyzed using Exiqon's miRCURY LNA microRNA Array. The differentially expressed miRNA were validated by real‐time quantitative polymerase chain reaction. We found that the expression levels of miR‐224‐3p and miR‐4712‐3p were upregulated, and miR‐3940‐5p was downregulated in the PBMC. The common clinical immune modulator Tα1 changed the miRNA expression profile. Our analysis showed that differentially expressed miRNA were associated with the mechanism of immune imbalance of vitiligo and that Tα1 could play an important role in changing the expression of these miRNA in the PBMC of patients with NSV. This study provided further evidence that miRNA may serve as novel drug targets for vitiligo therapeutic evaluation.  相似文献   
996.
Bipolar disorder (BD) is a highly heritable psychiatric disorder characterised by recurrent episodes of mania and depression. Many studies have reported altered gene expression in BD, some of which may be attributable to the dysregulated expression of miRNAs. Studies carried out to date have largely studied medicated patients, so it is possible that observed changes in miRNA expression might be a consequence of clinical illness or of its treatment. We sought to establish whether altered miRNA expression might play a causative role in the development of BD by studying young, unmedicated relatives of individuals with BD, who are at a higher genetic risk of developing BD themselves (high-risk individuals). The expression of 20 miRNAs previously implicated in either BD or schizophrenia was measured by qRT-PCR in whole-blood samples from 34 high-risk and 46 control individuals. Three miRNAs, miR-15b, miR-132 and miR-652 were up-regulated in the high-risk individuals, consistent with previous reports of increased expression of these miRNAs in patients with schizophrenia. Our findings suggest that the altered expression of these miRNAs might represent a mechanism of genetic susceptibility for BD. Moreover, our observation of altered miRNA expression in the blood prior to the onset of illness provides hope that one day blood-based tests may aid in the risk-stratification and treatment of BD.  相似文献   
997.
Glucocorticoid (GC) resistance is a severe problem associated with various inflammatory diseases. Previous studies have shown that repeated social stress induces GC resistance in innate immune cells, but the underlying molecular mechanisms have not been fully elucidated. Therefore, the purpose of this study was to examine potential underlying molecular mechanism(s) of repeated social defeat (RSD) stress on GC resistance in splenic macrophages. It was hypothesized that mRNA expression of receptors for GC and nuclear translocating-associated regulators in splenic macrophages would be affected by RSD, and that these changes would be associated with epigenetic modification. The data showed that the mRNA expression of GC and mineralocorticoid receptors were significantly decreased in splenic macrophages by RSD. RSD also induced a significantly decreased mRNA expression in FK506-binding protein 52 (FKBP52), consequently resulting in a significantly increased ratio of FKBP51 to FKBP52. Moreover, DNA methyltransferases 3a and 3b showed a significant decrease in their mRNA expression in the RSD group as did mRNA expression of histone deacetyltransferase 2. The RSD group also showed a significantly reduced quantity of methylated DNA in splenic macrophages. Based on microRNA (miRNA) profiling data, it was determined that RSD induced significantly increased expression of 9 different miRNAs that were predicted to interact with mRNAs of the GC receptor (6 miRNAs), mineralocorticoid receptor (3 miRNAs) and FKBP52 (2 miRNAs). Spearman correlation analysis revealed significantly strong correlations between the expression of 2 miRNAs and their target mRNA expression for GC receptors. Among these miRNAs, we verified direct effects of miRNA-29b and -340 overexpression on mRNA expression of GC receptors in L929 cells. The overexpression of miRNA-29b or -340 in L929 cells significantly reduced LPS-induced overexpression of GC receptors. In conclusion, this study provides evidence that epigenetic regulation, such as DNA methylation and miRNA expression, may play a role in the RSD-induced GC resistance that we have observed in splenic macrophages.  相似文献   
998.
Schistosomiasis (SCH) is the second only to malaria among the parasitic diseases affecting humans regarding the prevalence of infection worldwide. In this nonsystematic review, we summarize the existing data on commercially available and promising investigational urine markers for the detection of SCH and its associated bladder cancer (BC). We searched PubMed, Scopus and Cochran without time limits. We reviewed the recent literatures on urine-based markers for SCH and its associated BC. Many studies identified several urine biomarkers of Schistosoma haematobium and Schistosoma mansoni worms and their associated BC using automated, inexpensive, quantitative assays in urine. These markers may aid in early detection of bladder carcinoma and have the potential to reduce the number of follow-up cystoscopy, thus reducing healthcare costs and patient discomfort, at the same time. Nevertheless, clinical evidence is insufficient to warrant the substitution of the cystoscopic follow-up scheme by any of the currently available urine marker tests.  相似文献   
999.
1000.
MicroRNA (miRNA) plays a significant role in suppressing the occurrence and development of tumor by inhibiting the translation of target proteins. Although previous researches have verified many miRNAs’ functions in bladder cancer (BC), the function of miR-188-5p and miR-141-3p in BC still remains unknown. Our experiment manifested that miR-188-5p and miR-141-3p were highly expressed in BC tissues and cells, which indicated a poor prognosis. In vitro functional assays suggested that down-regulated miR-188-5p and miR-141-3p inhibited the proliferation, migration and invasion of BC cells, while a combination of half dose down-regulated miR-188-5p and half dose down-regulated miR-141-3p demonstrated a more obvious inhibition effect. All results indicated that miR-188-5p and miR-141-3p promoted BC respectively and synergistically. Therefore, miR-188-5p and miR-141-3p will not only assist the diagnosis of BC, but also serve as more effective joint markers to predict the progression of BC.  相似文献   
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