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31.
A series of carbamate derivatives of the H(3) antagonist ROS203 (1) were prepared, and their lipophilicity and steric hindrance were modulated by introducing linear or branched alkyl chains of various lengths. In vitro stability studies were conducted to evaluate how structural modulations affect the intrinsic reactivity of the carbamoyl moiety and its recognition by metabolic enzymes. Linear alkyl carbamates were the most susceptible to enzymatic hydrolysis, with bioconversion rates being higher in rat liver and plasma. Chain ramification significantly enhanced the enzymatic stability of the set, with two derivatives (1g and 1h) being more stable by a factor of 8-40 than the ethyl carbamate 1a. Incubation with bovine serum albumin (BSA) showed a protective role of proteins on chemical and porcine-liver esterase (PLE)-catalyzed hydrolysis. Ex vivo binding data after i.v. administration of 1h revealed prolonged displacement of the labeled ligand [(3)H]-(R)-alpha-methylhistamine ([(3)H]RAMHA) from rat-brain cortical membranes, when compared to 1. However, the high rates of bioconversion in liver, as well as the chemical instability of 1h, suggest that further work is needed to optimize the enzymatic and chemical stability of these compounds.  相似文献   
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Previous studies have shown that microRNA-206 (miR-206) exhibits anti-tumour properties in various tumours. Nevertheless, diagnostic significance of miR-206 in oral cancer is still poorly known. Our research was carried out to explore the performance of miR-206 in the diagnosis of oral cancer. Quantitative real-time polymerase chain reaction (qRT-PCR) method was adopted to measure the level of miR-206 in serum specimens from oral cancer cases and control individuals. Chi-square test was performed to analyse the correlation between miR-206 level and clinicopathological parameters of the cases. Receiver operating characteristic (ROC) curve was constituted to assess diagnostic accuracy of miR-206 in oral cancer. Serum miR-206 level in oral cancer patients was significantly lower than that in control individuals (P < .001). miR-206 expression was obviously related to T classification (P = .033), TNM stage (P = .008) and lymph node metastasis (P = .028). The area under the curve (AUC) of the ROC curve was 0.846 (95% CI = 0.797-0.896, P < .001) with a specificity of 72.7% and a sensitivity of 81.2%. It revealed that miR-206 might be a non-invasive indicator in differentiating oral cancer cases from control individuals. Down-regulation of miR-206 is related to the development of oral cancer. Serum miR-206 might be an effective indicator for early detection of oral cancer.  相似文献   
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Arterial calcification is a common feature of cardiovascular disease. Sortilin is involved in the development of atherosclerosis, but the specific mechanism is unclear. In this study, we established calcification models in vivo and in vitro by using vitamin D3 and β-glycerophosphate, respectively. In vivo, the expression of SORT1 was up-regulated and the expression of miR-182 was down-regulated in calcified arterial tissues. Meanwhile there was a negative correlation between SORT1 expression and miR-182 levels. In vitro, downregulating SORT1 expression using shRNA inhibited β-glycerophosphoric induced vascular smooth muscle cells (VSMCs) calcification. Moreover, reduced sortilin levels followed transfection of miR-182 mimics, whereas there was a significant increase in sortilin levels after transfection of miR-182 inhibitors. A luciferase reporter assay confirmed that SORT1 is the direct target of miR-182. Our study suggests that SORT1 plays a vital role in the development of arterial calcification and is regulated by miR-182.  相似文献   
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Wound healing is regulated by a complex network of cells, molecules, and cytokines, as well as microRNAs (miRNAs). miRNAs were confirmed to influence the wound healing process, and miR-21, an important member of the miRNA family, was also shown to regulate wound healing. The aim of the present study was to investigate the role of miR-21 in the wound healing process and the possible underlying cell signaling pathways. We isolated GMSCs from WT and miR-21-KO mouse gingiva. Flow cytometric analysis and immunocytofluorescense staining were used to identify the GMSCs acquired from WT and miR-21-KO mice. RT-PCR, western blot analysis and immunohistofluorescence staining were performed to examine the expression of extracellular matrix components and key proteins of cell signaling pathways. TargetScan and pmiR-RB-REPORT vectors were used to verify that Smad7 was a direct target of miR-21. Compared to WT mice, miR-21-KO mice showed slower wound healing. RT-PCR and western blot analysis indicated that Elastin expression was downregulated in miR-21-deficient samples. We confirmed that Smad7 was a direct target of miR-21. miR-21 knockout resulted in increased expression of Smad7 and impaired phosphorylation of the Smad2/3 complex. The expression of the Smad7-Smad2/3-Elastin axis in palate tissues sections acquired from WT and miR-21-KO mice showed the same trend. Based on all these results, we demonstrated that miR-21 promoted the wound healing process via the Smad7-Smad2/3-Elastin pathway.  相似文献   
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目的:研究microRNA-151-5p(miR-151-5p)在两肾一夹(2K1C)肾血管性高血压大鼠中的表达,并为miR-151-5p参与调节血管内皮细胞功能提供理论依据。方法:建立2K1C大鼠模型,获得胸主动脉血管内皮,采用荧光定量PCR技术检测血管内皮细胞中miR-151-5p的表达,通过数据库及生物信息学软件预测miR-151-5p的靶基因,并对靶基因进行GO富集和KEGG pathway分析。结果:与假手术组大鼠相比较,实验组大鼠胸主动脉血管内皮细胞miR-151-5p的表达量显著升高(P0.05)。GO分析显示miR-151-5p的靶基因参与蛋白加工水解、Notch受体加工等多种生物学功能(P0.01);KEGG pathway分析显示miR-151-5p的靶基因参与Notch信号通路、血管平滑肌收缩、代谢途径、细菌感染和RNA转运等信号通路。结论:2K1C大鼠血管内皮细胞中miR-151-5p表达升高,可能通过对其靶基因APH1A的调控参与血管内皮细胞功能调节。  相似文献   
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Circular RNAs (circRNAs) have recently shown capabilities as gene regulators in mammals. Some of them interact with microRNAs (miRNAs) and function as sponges to affect related miRNAs' activities. In this study, the molecular function of circRNA_0009910 and its potential downstream miRNA targets were explored. The expression levels of hsa_circ_0009910 were found to be overexpressed in osteosarcoma (OS) cells. Knockdown of circ_0009910 induced cell proliferation inhibition, cell cycle arrest, and apoptosis in OS cells. The target miRNA was predicted to be miR-449a, whose expression was downregulated in OS cells. Inhibition of miR-449a abolished the effect of circ_0009910 knockdown on cell growth and apoptosis. The expression of miR-449a were found to be negatively correlated with that of circ_0009910 in OS tissues. Direct interaction of circ_0009910 and miR-449a was confirmed through dual-luciferase assays. Moreover, IL6R was predicted as a potential target of miR-449a. Overexpression of miR-449a decreased the mRNA and protein levels of IL6R. Restoration of IL6R impaired the miR-449a induced inhibition of cell proliferation, cell cycle arrest, and apoptosis. The mRNA expression of IL6R was inversely correlated with miR-449a in OS tissues. In addition, JAK1/STAT3 signaling pathway was regulated by circ_0009910/miR-449a/IL6R axis. Taken together, we suggested that circ_0009910 acted as a sponge of miR-449a and upregulated miR-449a functional target IL6R, thereby contributed to carcinogenesis of OS.  相似文献   
39.
摘要 目的:探究miR-939-5p对糖尿病性视网膜病变和人视网膜微血管内皮细胞(HRMEC)的调控作用。方法:将miR-939-5p模拟物(miR-939-5p-mimic)或miR-939-5p抑制剂(miR-939-5p-inhibitor)转染到HRMEC中,并将细胞用高糖(HG组,25 mM)或低糖(LG组,5 mM)处理24 h。通过细胞计数试剂盒8(CCK-8)来检测细胞活力,EdU法检测细胞DNA的复制能力,Hoechst 33258染色检测细胞凋亡,使用双荧光素酶试剂盒E2920验证miR-939-5p与NOS2 3''-UTR之间的结合关系。对大鼠腹腔注射65 mg/kg的链脲佐菌素(STZ)诱导DR模型,通过RT-qPCR检测miR-939-5p水平,Western Blot检测诱导型一氧化氮合酶(NOS2)水平,苏木精伊红(HE)染色检查大鼠视网膜形态,免疫组织化学染色检测视网膜Claudin-5和Occludin的表达,伊文思蓝染色检测大鼠血视网膜屏障(BRB)通透性,ELISA法检测大鼠房水中白介素-1β(IL-1β)和肿瘤坏死因子-α(TNF-α)的水平。结果:与LG组的HRMEC相比,HG组的miR-939-5p显著降低,而NOS2蛋白水平显著升高(P<0.05)。荧光素酶活性测定显示,与NC-mimic组相比,miR-939-5p-mimic与pGL3-NOS2-WT共转染组的荧光素酶活性显著降低(P<0.05)。与HG+NC-mimic组相比,HG+miR-939-5p-mimic组的miR-939-5p水平和细胞活力显著升高,而NOS2蛋白水平和细胞凋亡率显著降低(P<0.05)。与DR组相比,miR-939-5p-Agomir组大鼠视网膜组织病变减轻,Claudin-5和Occludin的表达水平明显升高,伊文思蓝浓度显著降低(P<0.05);与DR组相比,miR-939-5p-Agomir组大鼠房水中IL-1β和TNF-α的水平均显著降低(P<0.05)。结论:在高糖培养的HRMEC中和DR大鼠视网膜中,miR-939-5p为低表达模式,NOS2为高表达模式。上调miR-939-5p通过靶向抑制NOS2对DR大鼠视网膜和HRMEC提供保护作用。  相似文献   
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结直肠癌是我国常见的消化道恶性肿瘤。目前认为结直肠癌的形成是一个多因素、多步骤的过程,其具体发病机制尚不清楚。microRNA是一类非编码小分子RNA,能在转录后水平调控靶基因的表达,参与肿瘤的增殖、侵袭和转移,甚至调节肿瘤化疗敏感性。学者普遍认为mircroRNA-203(mir-203)是抗癌小分子RNA,但与以往不同的是mir-203在结直肠癌肿的表达水平仍存在争议。本文将概述mir-203在结直肠癌的发生、发展、诊断、预后以及药物抗性中发挥的各类生物学作用。阐述mir-203在结直肠癌不同信号通路中的作用,探索其在结直肠癌研究中的全部潜能。  相似文献   
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