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目的探讨miR-26b-3p在神经胶质瘤细胞中的表达,以及其对神经胶质瘤细胞增殖和转移的影响。方法采用荧光实时定量PCR(qRT-PCR)检测神经胶质瘤组织与癌旁组织中miR-26b-3p与TRA2B的表达水平;通过向神经胶质瘤细胞细胞系中转染miR-26b-3p mimic和inhibitor干扰内源miR-26b-3p的表达,同时检测其靶基因TRA2B蛋白的表达变化;采用CCK-8法检测各组神经胶质瘤细胞增殖能力的变化,以及划痕实验对癌细胞迁移能力进行评估。结果神经胶质瘤患者组织与癌旁组织比较,miR-26b-3p的表达水平显著上调,TRA2B的表达水平显著下降,差异有统计学意义(P<0.05);Pearson相关性分析显示,在32例神经胶质瘤患者神经胶质瘤组织中,TRA2B的表达水平与miR-26b-3p表达呈显著负相关(r=-0.510;P<0.05);SHG-44细胞体外转染实验结果发现,降低细胞内源miR-26b-3p的表达时,TRA2B的表达水平显著升高,细胞的增殖活性以及转移能力会被抑制;而上调细胞内源miR-26b-3p的表达时,TRA2B的表达水平显著下降,细胞的增殖活性与转移能力会显著提高,相比于对照组,差异有统计学意义(P<0.05)。结论 miR-26b-3p在神经胶质瘤组织中高表达,其可能靶向调控TRA2B的表达抑制神经胶质瘤细胞的增殖活性与转移能力,在神经胶质瘤的发生发展过程中起着重要的生理功能。  相似文献   
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Aim of the workTo measure interleukin-33 (IL-33) serum and synovial fluid (SF) levels as well as its relative expression in peripheral blood mononuclear cells (PBMC) of juvenile idiopathic arthritis (JIA) patients and to study their relation to clinical, laboratory and musculoskeletal ultrasound characteristics, disease activity and functional status.Patients and methodsThe study included 60 JIA patients and 60 healthy controls and SF levels were measured in 20. Juvenile arthritis disease activity score (JADAS27) and Juvenile Arthritis Multidimensional Assessment Report (JAMAR) were assessed; Ten-joint grey scale (GS) and power Doppler (PD) MSUS score was performed. Rheumatoid factor (RF) titer and C-reactive protein (CRP) levels were measured.ResultsIn JIA patients, serum IL-33 levels (median 12.6; 7.4–23.8 ng/l) and its relative mRNA expression (median 3.3; 2.5–3.7) were significantly higher than their levels in the controls (median 1.7; 0.8–2.4 ng/l and median 1 ng/ml; p < 0.001). Polyarticular subtype (n = 20) had higher IL-33 serum levels compared to oligoarticular (n = 28, p < 0.001) and systemic-onset (n = 12, p = 0.006) subtypes. In JIA patients, the serum and SF levels of IL-33 significantly correlated with JADAS27 (p < 0.001 and 0.002 respectively), CRP (p < 0.001 and 0.007 respectively), GS (p < 0.001 and 0.001 respectively) and PD (p < 0.001 and 0.005 respectively). Serum IL-33 correlated with RF (p = 0.039) while, SF IL-33 correlated with physical function (p = 0.02).ConclusionsJIA patients have significantly elevated IL-33 serum concentrations and mRNA expression that considerably correlated with different inflammatory parameters, RF and physical function suggesting that it could be a valuable marker of JIA disease activity and implies a possible prognostic role.  相似文献   
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Angiogenesis has been found as an attractive target for drug therapy as it is necessary for tumor growth. Accumulating evidences show that microRNAs (miRNAs), which are a group of highly conserved, single-stranded, short non-coding RNAs, play important roles through directly targeting angiogenic factors and protein kinases. The purpose of this study is to investigate the role of miR-195 in breast cancer development and angiogenesis through targeting IRS1. We show that miR-195 is inversely related with Insulin receptor substrate 1 (IRS1) in both breast cancer cells and breast cancer tissues. Induction of miR-195 could suppress IRS1 protein expression through binding to its 3′UTR regions either by transfection with miR-195 oligo or by infection with lentivirus encoding miR-195 gene. Moreover, re-expression of IRS1 reverses miR-195-mediated repression of tumor cell growth and miR-195 inhibits tumor angiogenesis through suppressing IRS1-VEGF axis. These data suggest that miR-195 mimics are potential therapeutic agents for breast cancer diagnose.  相似文献   
36.
通过对通用型在细菌中可溶性表达scFv-Fc抗体载体的构建,对抗IL-33全人源scFv-Fc抗体进行可溶性表达并鉴定。扩增人IgG1Fc片段及前期筛选的抗IL-33单链抗体(scFv)DNA,分别插入到改建的载体pLZ16中,构建可溶性重组表达pLZ16-scFv-Fc质粒。将重组质粒转入E.coli DH5αF’,菌落经PCR和测序验证表明我们成功构建了pLZ16-scFv-Fc重组质粒。将阳性克隆子分别于32℃IPTG表达5h或25℃无IPTG表达50h,用HRP标记抗人IgG1Fc抗体进行检测,结果显示25℃无IPTG表达50h时,表达蛋白分泌在细菌周质间,可明显检测到scFv-Fc的可溶性表达;western blotting结果显示,25℃无IPTG表达的scFv-Fc为65kD左右,其可溶性表达量较32℃表达量高。本研究成功构建了pLZ16-scFv-Fc重组质粒,并在E.coli DH5αF’中成功可溶性表达抗IL-33全人源scFv-Fc抗体。  相似文献   
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目的检测肾细胞癌组织及相应癌旁正常组织中miR-7的表达,分析18达与临床病理特征之间的关系,为进一步研究miR-7在肾癌的发生发展中作用奠定基础。方法收集48例经手术切除的配对肾癌及癌旁组织标本,提取组织中总RNA,经逆转录获得cDNA,采用实时荧光定量PCR(RT-qPCR)方法检测标本中miR-7表达量,并通过统计学软件分析其表达量与患者临床病理特征之间的相关性。结果与相应癌旁组织相比,肾癌组织中miR-7表达量明显升高,其中34例(70.8%)肾癌标本miR-7表达上调,14例(29.2%)表达下调,差异有统计学意义(P〈0.05)。肾细胞癌中miR-7表达上调与患者年龄、性别、肾癌组织类型、TNM分期、AJCC临床分期无相关性(P〉0.05)。结论 miR-7在肾癌组织中明显高表达,提示其可能与肾癌的发生和发展相关,可能成为肾癌早期诊断、治疗乃至预后判断的新的生物标记物。  相似文献   
40.
《Injury》2018,49(8):1617-1622
Surgical treatment of AO/OTA type 33-C fractures is a therapeutic challenge despite advances in surgical instruments and techniques. We introduce a novel surgical technique named transient retrograde interfragmentary compression (TRIC) to help intraarticular fragment reduction in AO/OTA type 33-C fracture. We inserted a partial threaded 7.0-cannulated screw with a washer along the transepicondylar axis from the medial femoral epicondyle during the articular block reduction process of AO/OTA type 33-C fractures to strengthen the compressive force between the condylar fragments and to enhance the handling of the articular block fragment in the alignmental correction stage. Following the provisional reduction and fixation using lateral distal femur locking compression plate, TRIC screw was removed. Fifteen AO/OTA type 33-C distal femoral intraarticular fractures of thirteen patients were surgically treated using the TRIC technique. We analyzed the radiographic result of the patients by measuring the horizontal gap and vertical step-off in the postoperative radiographs. Mean horizontal fracture gap was 0.34 mm and mean vertical step-off between bicondylar fragments was 0.63 mm. The median value of the horizontal fracture gap and vertical step off was 0 and 0.46 mm, respectively. Mean time to union in the bicondylar fracture fragment was 9 week. TRIC is considered to be a valuable surgical reduction technique in the treatment of the AO/OTA 33-C type fractures.  相似文献   
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