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Hepatocellular carcinoma (HCC) is a highly aggressive solid malignancy throughout the world. Dysregulation of miRNAs play essential roles in HCC progression via aberrant regulation of cell proliferation, apoptosis, as well as metastasis. miR-663a is a poorly investigated miRNA. Whether miR-663a regulates HCC development remains unknown. The aim of the study was to explore the role of miR-663a in HCC development. To determine the expression level of miR-663a in HCC, we analyzed the data from GSE21362 and TCGA. The results showed that miR-663a was significantly down-regulated in HCC tissue compared with adjacent non-tumor tissue. Gain of function and loss of function assays revealed that miR-663a distinctly inhibited cell proliferation, migration and invasion. Mechanistic investigations demonstrated that miR-663a modulated cell functions through targeting and suppressing high mobility group A2 (HMGA2). In addition, overexpression of HMGA2 remarkably attenuated the tumor repressive effect of miR-663a. Taken together, miR-663a inhibits HCC cell proliferation and motility by targeting HMGA2.  相似文献   
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Conclusions: The present study indicates that miR-21 is involved in progression from normal to pre-malignant laryngeal lesions (PLLs) and from PLLs to laryngeal squamous cell carcinoma (LSCC). Furthermore, normalized PCR results for miR-21 might be used to discriminate between normal and ordinary hyperplasia before the emergence of dysplasias and pre-malignant lesions with malignant potential. Objective: To investigate a sensitive marker that contributes to progression from normal tissue to PLLs and from PLLs to LSCC. Methods: In 116 PLLs and LSCC patients and 19 without dysplasia matched sets of tissue and plasma samples from Beijing Tongren Hospital, miR-21 was analysed by droplet digital PCR and quantitative real-time polymerase chain reaction based on paraffin-embedded tumour tissue and plasma. Results: Compared with controls, miR-21 levels in tissue and plasma were significantly higher for both PLL and LSCC groups (for both groups vs controls: p p?相似文献   
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目的 探讨高危型人乳头状瘤病毒(high risk-human papilloma virus, HR-HPV)阳性宫颈癌患者组织及血清中微小RNA(microRNA, miRNA)-34a-5p的表达及其对宫颈癌的诊断价值。方法 将100例HR-HPV阳性宫颈癌患者(宫颈癌组)、70例宫颈上皮内瘤变(cervical intraepithelial neoplasia, CIN)患者(CIN组)、70例HR-HPV阳性子宫良性病变或者HPV单纯阳性的健康体检者(对照组)作为研究对象。采集上述研究对象的血清标本及70例行手术治疗的宫颈癌组患者癌组织及癌旁组织。使用实时荧光定量PCR技术测定组织及血清中miRNA-34a-5p水平,并分析miRNA-34a-5p与宫颈癌临床、病理指标的关联及血清miRNA-34a-5p对宫颈癌的诊断价值。结果 ①对照组血清中miRNA-34a-5p的相对表达量高于CIN组和宫颈癌组:(0.933±0.097)vs.(0.554±0.099)vs.(0.369±0.099),差异有统计学意义(F=741.401,P=0.000);宫颈癌组患者术前血清中miRNA-34a-5p相对表达量低于术后1周,差异有统计学意义(t=8.305,P=0.000)。有无淋巴结转移和有无远处转移的宫颈癌患者血清中miRNA-34a-5p相对表达量的差异有统计学意义(P均<0.05)。②宫颈癌组患者癌旁组织中miRNA-34a-5p的相对表达量高于癌组织,差异具有统计学意义(t=40.313,P=0.000)。③宫颈癌组患者癌组织中的miRNA-34a-5p表达水平与血清中的表达水平呈正相关(r=0.908,P=0.000)。④以0.508为miRNA-34a-5p相对表达量的最佳临界值诊断宫颈癌,其灵敏度为83.6%,特异度为79.4%,AUC为0.860,95%置信区间为0.803~0.917。结论 HR-HPV阳性宫颈癌患者癌组织和血清中miRNA-34a-5p表达下调,对宫颈癌诊断及预后监测具有一定的参考价值。  相似文献   
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目的检测miRNA-34c在鼻咽癌组织中的表达情况,并探讨其在鼻咽癌发生、发展中的意义。方法以实时定量聚合酶链式反应(quantitative real-time polymerase chain reaction,qRT-PCR)方法检测28例鼻咽癌石蜡包埋组织中相对于28例鼻咽部慢性炎症石蜡包埋组织中miRNA-34c的差异表达情况,并结合临床资料及随访结果分析miRNA-34c与鼻咽癌病例临床因素的相关性。结果鼻咽癌组织中miRNA-34c的相对表达量明显低于鼻咽部慢性炎症组织,差异有统计学意义(P<0.05)。且随着临床分期的增高、淋巴结转移,miRNA-34c的表达呈下降趋势。结论 miRNA-34c可能参与鼻咽癌的发生与发展,调控miRNA-34c的表达量有望为鼻咽癌的治疗提供一种新的思路或方法。  相似文献   
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Survival with a good quality of life after cardiac arrest continues to be abysmal. Coordinated resuscitative care does not end with the effective return of spontaneous circulation (ROSC)—in fact, quite the contrary is true. Along with identifying and appropriately treating the precipitating cause, various components of the post–cardiac arrest syndrome also require diligent observation and management, including post–cardiac arrest neurologic injury and myocardial dysfunction, systemic ischemia-reperfusion phenomenon with potential consequent multiorgan failure, and the various sequelae of critical illness. There is growing evidence that an early invasive approach to coronary reperfusion with percutaneous coronary intervention, together with active targeted temperature management and optimization of hemodynamic, ventilator, and metabolic parameters, may improve survival and neurologic outcomes in cardiac arrest survivors. Neuroprognostication is complex, as are survivorship issues and long-term rehabilitation. Our paramedics, emergency physicians, and resuscitation specialists are all to be congratulated for ever-increasing success with ROSC… but now the real work begins.  相似文献   
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目的探讨miRNA-449a在肺癌组织中的表达及其临床应用价值。方法收集右江族医学院附属医院2011年1月1日~2013年6月30日收治的58例肺癌患者为研究对象,采用反转录荧光定量聚合酶链式反应(RT-PCR)检测miRNA-449a在肺癌组织和癌旁正常组织中的表达量,分析miRNA-449a与临床病理特征的关系,并采用荧光电子显微镜观察miRNA-449a模拟物对体外培养肺癌细胞株95D细胞凋亡的影响。结果鳞癌组和腺癌组miRNA-449a平均表达量均明显低于癌旁正常对照组(LSD-t=6.712,P=0.000;LSD-t=4.572,P=0.000),其相对表达量与瘤体大小(u=78.412,P=0.012)有关,与患者年龄(u=920.000,P=0.615)、性别(u=800.000,P=0.215)、病理类型(χ2=4.221,P=0.155)和临床分期(u=754.000,P=0.009)无关。与阴性对照组比较,miRNA-449a模拟物可明显促进肺癌细胞的凋亡,且呈剂量依赖性。结论 miRNA-449a在肺癌组织中呈低表达,可诱导肺癌细胞凋亡,发挥抑癌基因的作用,可能成为肺癌早期诊断与治疗的新分子靶标。  相似文献   
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The principle of empirical therapy for patients with intra-abdominal infections (IAI) should include antibiotics with activity against Enterobacteriaceae and Bacteroides fragilis group species. Coverage of Pseudomonas aeruginosa, Enterobacter cloacae, and Enterococcus faecalis is also recommended for hospital-associated IAI. A nationwide survey was conducted to investigate the antimicrobial susceptibility of pathogens isolated from postoperative IAI. All 504 isolates were collected at 26 institutions and referred to a central laboratory for susceptibility testing. Lower susceptibility rates to ciprofloxacin and cefepime were demonstrated in Escherichia coli. Among E. coli, 24.1% of strains produced extended-spectrum β-lactamase (ESBL). Carbapenems, piperacillin/tazobactam, cephamycins/oxacephem, aminoglycosides, and tigecycline had high activity against E. coli, including ESBL-producing isolates. Among E. cloacae, low susceptibility rates to ceftazidime were demonstrated, whereas cefepime retained its activity. P. aeruginosa revealed high susceptibility rates to all antimicrobials tested except for imipenem. Among B. fragilis group species, low levels of susceptibility were observed for cefoxitin, moxifloxacin, and clindamycin, and high susceptibility rates were observed for piperacillin/tazobactam, meropenem, and metronidazole. Ampicillin, piperacillin, and glycopeptides had good activity against E. faecalis. Imipenem had the highest activity against E. faecalis among carbapenems. In conclusion, we suggested the empirical use of antimicrobials with the specific intent of covering the main organisms isolated from postoperative IAI. Piperacillin/tazobactam, meropenem, or doripenem, are appropriate in critically ill patients. Combination therapy of cefepime (aztreonam in patients with β-lactam allergy) plus metronidazole plus glycopeptides, imipenem/cilastatin or cephamycins/oxacephem plus ciprofloxacin plus metronidazole are potential therapeutic options.  相似文献   
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成力  李小庆  陈文江  陈灿 《重庆医学》2015,(36):5103-5106
目的:探讨 miRNA-126-3p 与肺动脉高压(以下简称肺高压)发病机制的相关性。方法选取25例先天性心脏病患者,其中,肺高压患者11例,对照组14例,采用 qRT-PCR 法检测其肺组织 miRNA-126-3p 的表达,并采用 starBase 进行靶基因预测,并从 mRNA 水平和蛋白水平进行验证。结果肺高压患者与对照组在年龄、性别、生化指标检查等方面比较差异无统计学意义(P>0.05);肺高压患者 miRNA-126-3p 表达水平与对照组比较差异有统计学意义(P<0.01);生物信息学预测发现 miRNA-126-3p 的生物学功能主要与结合蛋白、信号转导、细胞分化、调控细胞形态、调控 MAPK 和胰岛素受体信号通路等有关,其靶基因主要有 VEGFA 、SPRED1、PIK3R2等;肺高压组的 VEGFA 表达在 mRNA 水平和蛋白水平与对照组比较差异有统计学意义(P<0.01);miRNA-126-3p 与 VEGFA 呈现正相关(P<0.01)。结论 miRNA-126-3p 可能通过调控 VEGFA 参与先天性心脏病相关性肺动脉高压发病。  相似文献   
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