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目的:利用整合生物信息学手段分析EZH2(enhancer of zeste 2 polycomb repressive complex 2 subunit)基因在乳腺癌中的表达及其临床意义。方法:在肿瘤基因组计划数据库(The Cancer Genome Atlas,TCGA)中下载乳腺癌与正常乳腺组织的基因表达谱数据,进一步利用Ualcan数据库和人类蛋白质图谱(The Human Protein Atlas)数据库数据分析EZH2基因在乳腺癌中的mRNA及蛋白表达水平。利用Ualcan数据库分析EZH2基因的甲基化水平并筛选其共表达基因;对EZH2及其共表达基因进行GO(Gene Ontology)富集分析和KEGG通路分析以明确EZH2的共表达基因参与的生物学过程和相关通路;使用Kaplan-Meier生存分析法分析乳腺癌患者的总生存期、无病生存期、无远处转移生存期及后进展生存期与EZH2基因表达水平的关系并绘制生存曲线。结果:与正常乳腺组织相比,EZH2在乳腺癌组织中的mRNA及蛋白表达量明显升高。而EZH2的甲基化程度在乳腺癌组织与正常乳腺组织中则差异不明显。同时,EZH2的表达水平与年龄、乳腺癌分期及乳腺癌分子分型等因素密切相关。EZH2及其共表达基因主要参与了核碱基的调节、细胞周期调控、染色体分离、DNA复制、DNA修复等生物学过程,并参与了细胞周期、DNA 复制、M/G1期转化、M期、有丝分裂前中期、ATM通路等生物学通路。此外,EZH2基因表达水平高的乳腺癌患者的总生存期、无病生存期、无远处转移生存期及后进展生存期均明显低于EZH2基因低表达的患者。结论:EZH2在乳腺癌组织中高表达并且与患者不良预后密切相关。同时,EZH2的表达水平与乳腺癌的发生、发展密切相关。EZH2在乳腺癌诊断、靶向治疗及预后分析中具有重要的临床意义。  相似文献   
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目的研究快速成型(RP)技术辅助下制作的个体化假体复合珊瑚羟基磷灰石(CHA)、重组人骨形成蛋白2(rhBMP-2)修复兔下颌骨缺损的成骨效果。 方法以27只新西兰大白兔为实验对象,随机数字表法平均分成3组(每组9只),全部建立下颌骨连续性缺损模型,并在兔下颌骨缺损区分别植入个体化假体+自体骨(A组)、个体化假体+CHA(B组)、个体化假体+CHA+rhBMP-2(C组)。分别于术后4、12、24周3个时间点处死动物取材,进行大体标本观察,以及骨钙素(OC)、Ⅰ型胶原(COL-1)的免疫组化观察,分别比较各组修复骨缺损的能力,并对实验数据进行重复测量设计资料的单因素方差分析。 结果术后24周各组实验兔外形均对称,通过OC及COL-1的吸光度检测,骨缺损区均有大量新骨形成,A组(0.537 ± 0.010)、C组(0.530 ± 0.010)可见大量骨小梁及编织骨结构,缺损区的新骨OC、COL-1的免疫组化观察基本一致,差异无统计学意义(t = 0.007,P>0.05);但A组强于B组(0.415 ± 0.009,t = 0.122,P<0.001);C组也强于B组(t = 0.121,P<0.001),差异均有统计学意义。 结论在兔下颌骨缺损修复中,通过RP技术和组织工程技术相结合,CHA复合rhBMP-2后成骨能力明显增强,成骨效能肯定,为后期的临床应用提供可靠的实验基础。  相似文献   
155.
Sodium-glucose cotransporter-2 inhibitors (SGLT2 inhibitors) are a new type of drug for the treatment of diabetes, and they have been proven to have a good hypoglycemic effect. Several lines of clinical evidence have shown that SGLT2 inhibitors can significantly reduce the risks of atherosclerosis, hospitalization for heart failure, cardiovascular death, and all-cause mortality and delay the progression of chronic kidney disease. Because of the protective effects of SGLT2 inhibitors on the heart and kidney, they are being studied for the treatment of heart failure and chronic kidney disease in patients without diabetes. Therefore, it is necessary for cardiologists, patients with diabetes, and nephrologists to fully understand this type of drug. In this review, we summarize the following three aspects of SGLT2 inhibitors: the recent clinical evidence of their cardiovascular benefits, their mechanisms of action, and their safety.  相似文献   
156.
BackgroundBacteremia causes a major worldwide burden, in terms of financial and productivity costs, as well the morbidity and mortality it can ultimately cause. Proper treatment of bacteremia is a challenge because of the species-dependent response to antibiotics. The T2Bacteria Panel is a U.S. Food and Drug Administration–cleared and culture-independent assay for detection of bacteremia, including common ESKAPE pathogens—Escherichia coli, Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, and Pseudomonas aeruginosa—and provides species identification in as little as 3.6 h directly from blood.ObjectiveOur aim was to evaluate the T2Bacteria assay performance and potential to affect patient care in the emergency department (ED).MethodsED patients from a Louisiana and Florida center were enrolled as part of the T2Bacteria Panel clinical study, which was prospective and noninterventional. Blood samples for blood culture (BC) and T2Bacteria were matched in time and anatomic location.ResultsData from 137 ED patients were evaluated. Relative to BC, T2Bacteria showed 100% positive percent agreement and 98.4% negative percent agreement. In addition, for species on the T2Bacteria Panel, the T2Bacteria assay detected 25% more positives associated with infection, and on average identified the infectious species 56.6 h faster. The T2Bacteria assay covered 70.5% of all species detected by BC. Finally, relative to actual care, the T2Bacteria assay could have potentially focused therapy in 8 patients, reduced time to a species-directed therapy in 4 patients, and reduced time to effective therapy in 4 patients.ConclusionsIn this ED population, the T2Bacteria assay was a rapid and sensitive detector of bacteremia from common ESKAPE pathogens and showed the theoretical potential to influence subsequent patient therapy, ranging from antibiotic de-escalation to faster time to effective therapy.  相似文献   
157.
【目的】评价复方番石榴制剂治疗超重肥胖2型糖尿病的临床疗效。【方法】将120例超重肥胖2型糖尿病患者随机分为治疗组和对照组各60例,治疗组给予口服二甲双胍肠溶片及复方番石榴制剂治疗,对照组给予口服二甲双胍肠溶片治疗,疗程均为12周。观察2组治疗前后腰围(WC)、体质量指数(BMI)、空腹血糖(FBG)、餐后2h血糖(P2hBG)、糖化血红蛋白(HbA1c)、胆固醇(TC)、甘油三酯(TG)、游离脂肪酸(FFA)等的变化情况,评估复方番石榴制剂的临床疗效。【结果】(1)中医证候总疗效:治疗后,治疗组的总有效率为95.00%,优于对照组的70.00%,差异有统计学意义(P0.01)。(2)治疗后,治疗组的WC和BMI均较治疗前显著下降(P0.01),而对照组均无明显下降(P0.05),治疗组对WC和BMI的下降作用均优于对照组(P0.05)。(3)治疗后,2组FBG、P2hBG、HbA1c、TC、TG、FFA水平均较治疗前显著改善(P0.05),且治疗组对上述各项指标的改善作用均优于对照组(P0.05)。(4)安全性评价:除治疗组有3例患者出现轻度的胃部不适感,未予特殊处理后自行缓解外,其余患者均未发现不良反应。【结论】复方番石榴制剂联合二甲双胍治疗超重肥胖2型糖尿病,疗效确切,可有效降糖、降脂、减肥及改善中医证候。  相似文献   
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Helicobacter pylori (H. pylori) is a main risk factor for gastric cancer (GC). Epithelial-mesenchymal transition (EMT) is involved in the development and progression of H. pylori-associated GC. However, the exact molecular mechanism of this process remains unclear. The AKT/GSK3β signaling pathway has been demonstrated to promote EMT in several types of cancer. The present study investigated whether H. pylori infection induced EMT, and promoted the development and metastasis of cancer in the normal gastric mucosa, and whether this process was dependent on AKT activation. The expression levels of the EMT-associated proteins, including E-cadherin and N-cadherin, were determined in 165 gastric mucosal samples of different disease stages by immunohistochemical analysis. The expression levels of E-cadherin, N-cadherin, AKT, phosphorylated (p-)AKT (Ser473), GSK3β and p-GSK3β (Ser9) were further determined in H. pylori-infected Mongolian gerbil gastric tissues and cells co-cultured with H. pylori by immunohistochemical analysis and western blotting. The results indicated that the expression levels of the epithelial marker E-cadherin were decreased, whereas the expression levels of the mesenchymal marker N-cadherin were increased during gastric carcinogenesis. Their expression levels were associated with H. pylori infection. Furthermore, H. pylori infection resulted in downregulation of E-cadherin expression and upregulation of N-cadherin expression in Mongolian gerbils and GES-1 cells. In addition, an investigation of the associated mechanism of action revealed that p-AKT (Ser473) and p-GSK3β (Ser9) were activated in GES-1 cells following co-culture with H. pylori. Furthermore, following pretreatment of the cells with the AKT inhibitor VIII, the expression levels of E-cadherin, N-cadherin, p-AKT and p-GSK3β did not show significant differences between GES-1 cells that were co-cultured with or without H. pylori. The levels of p-AKT and p-GSK3β were increased in H. pylori-infected Mongolian gerbils. In conclusion, the present study demonstrated that H. pylori infection activated AKT and resulted in the phosphorylation and inactivation of GSK3β, which in turn promoted early stage EMT. These effects were AKT-dependent. This mechanism may serve as a prerequisite for GC development.  相似文献   
160.
目的:探讨 miR-9 通过靶向 E 盒结合锌指蛋白 2(zinc finger E-box binding homeobox 2,ZEB2)对小细胞肺癌(small cell lung cancer,SCLC)细胞生物学行为的调控作用,分析miR-9在SCLC中的作用及其工作机制。方法:采用qPCR、WB和免疫组化方法检测于2018年2月至2019年11月于河北医科大学第四医院肿瘤内科接受手术治疗的67例SCLC患者癌组织及癌旁组织中ZEB2的表达。采用TargetScan预测miR-9的潜在靶基因并通过双荧光素酶报告基因试验、qPCR和WB法进行验证。CCK-8法、流式细胞术和Transwell实验检测miR-9和ZEB2 过表达对 NCI-H446 的生物学行为影响,WB法检测对细胞中E-cadherin,N-cadherin和Vimentin蛋白表达的影响。利用miR-9过表达NCI-H446细胞构建SCLC裸鼠移植瘤模型,观察miR-9对裸鼠移植瘤生长的影响。结果:SCLC组织中ZEB2的mRNA和蛋白表达水平明显高于癌旁正常组织(P<0.01)。miR-9在ZEB2的3'' UTR上具有潜在的结合位点,与对照组相比,miR-9过表达组NCI-H446细胞中ZEB2的mRNA和蛋白表达水平明显降低(P<0.01),细胞增殖、迁移和侵袭能力均显著下降(P<0.05或P<0.01),促EMT蛋白表达减少,而同时过表达ZEB2能够逆转上述影响。体内实验中,miR-9过表达组移植瘤体积、重量均明显低于对照组(P<0.05或P<0.01)。miR-9组裸鼠肿瘤组织中和ZEB2蛋白的表达均较对照组明显降低(P<0.01)。结论:miR-9通过靶向调控ZEB2从而抑制SCLC细胞的生物学行为以及NCI-H446裸鼠移植瘤的生长。  相似文献   
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