激光微切和巢式逆转录聚合酶链反应联合检测单个肝细胞的基因表达

目的 探讨检测单个肝细胞基因表达的方法。方法 应用激光微切的方法从冰冻切片上将单个肝细胞切下，提取总RNA，将RNA逆转录成cDNA，采用巢式逆转录聚合酶链反应（RT-PCR）检测mRNA的表达。结果 在显微镜下用紫外激光微切机，将单个肝细胞成功切下，提取RNA后，逆转录成cDNA，巢式RT-PCR的扩增产物在琼脂糖凝胶上清晰可见，其表达与细胞数量成正比。结论 联合应用激光微切和巢械RT-PCR可以检测单个肝细胞的基因表达。     

联合应用激光微切和实时定量PCR检测单个胰岛的基因表达

目的本研究中,我们联合应用激光微切和实时定量逆转聚合酶链反应(RT-PCR)检测胰岛的基因表达.     

实时荧光定量PCR在登革热病毒快速检测中的应用

目的应用实时荧光定量PCR快速检测登革热病毒感染。方法采集疑似登革热患者血清,采用实时荧光定量PCR检测登革热病毒,同时采用ELISA检测血清登革热IgM抗体。结果患者发病第7d血清登革热IgM血清抗体A值为0.236和0.237(临界值0.250),高度疑似阳性,第13d血清IgM抗体阳性。患者发病第2d,通用型核酸检测显示血清登革热病毒核酸含量较多,经过治疗,于第7d病毒拷贝下降。发病第2d,核酸检测确定感染病毒为登革热Ⅲ型;发病第13d血清登革Ⅲ型病毒核酸检测阴性。结论实时荧光定量PCR法具有准确性好、灵敏度高等优点,可用于登革热病毒感染的快速检测。     

定量RT-PCR方法检测衰老大鼠肾脏PAI-1基因的表达

目的采用SYBR 绿色荧光染料Ⅰ(SYBR GREENⅠ)定量PCR法,对来源珍贵的微量组织中的基因进行检测,并对其可行性及适用性进行研究. 方法取24月龄的老年大鼠、3月龄青年大鼠各6只,提取其肾脏组织的RNA, 采用SYBR GREEN I实时检测的逆转录-聚合酶链反应(RT-PCR)检测纤溶酶系活化剂抑制物-1(PAI-1)基因的表达,并用磷酸甘油醛脱氢酶(G3PDH)作为外参. 结果标准曲线有良好的相关性(R2>0.99),PCR产物特异,将PAI-1的拷贝数与G3PDH的拷贝数相除,青年大鼠肾脏PAI-1表达水平为(1.27±0.90)×10-3,老年大鼠肾脏PAI-1表达水平为(3.84±2.00)×10-3,两者比较,差异有显著性(P<0.05). 结论只要严格控制PCR反应条件,SYBR GREENⅠ定量PCR法可以作为一种良好的定量PCR方法对来源珍贵的微量组织的基因表达进行检测,并证实了老年大鼠肾脏PAI-1表达水平明显增加.     

实时定量PCR检测siRNA对小鼠巨噬细胞中FTH1基因表达的抑制作用

目的通过实时定量PCR(real-ti me PCR)检测基因表达的mRNA,建立一种直接观察小干扰RNA(si RNA)抑制目的基因表达的方法。方法化学设计合成对应于FTH1(ferritin heavy chain1,FTH1)基因表达mRNA的si RNA,经TurboFectTMin vitro Transfection Reagent转染小鼠RAW264.7巨噬细胞,48h后,提取总RNA,逆转录为cDNA。以3-磷酸甘油醛脱氢酶(glyceraldehyde-3-phosphate dehydrogenase,GAPDH)为内参,定量检测FTH1的表达,比较干扰前后FTH1基因mRNA的量。结果 3种si RNA处理的小鼠巨噬细胞中FTH1基因的表达抑制率最高为97.60%。结论实时定量PCR方法的建立为研究布鲁氏菌在侵染巨噬细胞过程中FTH1的功能提供了有效途径。     

鼠类携带淋巴细胞脉络丛脑膜炎病毒实时荧光定量RT-PCR检测方法的建立

目的建立检测鼠类携带淋巴细胞脉络丛脑膜炎病毒（lymphocytic choriomeningitis virus,LCMV）的实时荧光定量RT-PCR方法。方法根据LCMV核蛋白编码基因序列设计合成特异性引物对和TaqMan荧光探针,经优化反应体系和条件,建立LCMV实时荧光定量RT-PCR检测方法,然后进行灵敏度、特异性和重复性试验,并对79份宁波口岸捕获的鼠样品进行检测。结果建立实时荧光定量RT-PCR方法对鼠肺总RNA检测的灵敏度为20pg,是常规PCR方法的100倍;试验的重复性良好,CV值为0.85%;试验的特异性为100%。用该方法检测79份鼠样品有3份LCMV阳性,与常规RT-PCR结果一致。结论成功建立了鼠LCMV实时荧光定量RT-PCR检测方法,对于监测和防控鼠传LCM有重要意义。     

实时荧光定量PCR检测胆囊结石中华支睾吸虫DNA的研究

目的运用基于Taqman探针实时荧光定量PCR技术检测胆囊结石中的华支睾吸虫DNA。方法选取2012年3～4月份40例实施内镜取石保胆手术患者的胆囊结石,通过傅里叶红外光谱法分析结石成分,对结石研磨涂片镜检观察,并提取其DNA,运用实时荧光定量PCR技术检测华支睾吸虫基因。结果 40例患者的胆囊结石按主要成分可分为胆色素性结石(25例),胆固醇性结石(6例),混合性结石(9例)。结石涂片镜检有23例发现华支睾吸虫虫卵(阳性率57.5%),其中胆色素性结石19例,混合性结石4例。实时荧光定量PCR检测华支睾吸虫DNA阳性率为65.0%(26/40),其中包括23例镜检虫卵阳性标本及3例镜检阴性标本。结论运用实时荧光定量PCR在胆囊结石中检测出华支睾吸虫DNA,敏感性高于镜检法查虫卵。这不仅为华支睾吸虫感染诱发胆囊结石形成提供了分子生物学证据,同时也提供了一种诊断华支睾吸虫感染的有效手段,对胆囊结石病人的病因诊断、临床治疗以及术后预防复发等具有重要的指导意义。     

中东呼吸综合征冠状病毒实时荧光定量PCR检测方法的建立

目的建立一种快速、敏感、特异的实时荧光定量PCR(Real-time PCR)方法,用于中东呼吸综合征冠状病毒(MERS-CoV)的检测。方法根据中东呼吸综合征冠状病毒S蛋白基因的保守序列设计并合成一对引物及一条特异性TaqMan探针。通过条件优化,以10倍系列稀释重组质粒为标准品,进行Real-time PCR扩增,绘制标准曲线,并进行重复性、准确性、特异性及敏感性检测。结果建立的Real-time PCR方法检测中东呼吸综合征冠状病毒所绘制标准曲线的相关系数0.99,灵敏度为1.00×101拷贝,高于常规PCR方法(1.00×102拷贝);用该方法检测中东呼吸综合征冠状病毒基因为阳性,其他6种对照呼吸道病原体及冠状病毒基因检测均呈阴性;批内、批间重复试验的变异系数均1%。结论建立的中东呼吸综合征冠状病毒Real-time PCR检测方法灵敏、特异、重复性好,可用于中东呼吸综合征冠状病毒感染的快速诊断和流行病学调查。     

实时荧光定量PCR检测新型冠状病毒的不确定度评定

目的评定实时荧光定量PCR检测新型冠状病毒不确定度。方法按照JJF 1059.1-2012《测量不确定度评定与表示》分析和评定检测结果,以测量重复性为A类不确定度,以温度、仪器、微量移液器和标准物质等引入的因素为B类不确定度。结果A类不确定度为1.59×10^(-3),B类不确定度为0.444,合成不确定度为0.444,扩展不确定度为0.888(k=2)。结论测量不确定度的主要来源是B类不确定度,其中标准物质和移液器转移量不确定度占主要因素;而测量复现性引入的A类不确定度可忽略。     

Gene expression patterns in synchronized islet populations

In vivo levels of insulin are oscillatory with a period of ~5–10 minutes, indicating that the islets of Langerhans within the pancreas are synchronized. While the synchronizing factors are still under investigation, one result of this behavior is expected to be coordinated and oscillatory intracellular factors, such as intracellular Ca²⁺ levels, throughout the islet population. In other cell types, oscillatory intracellular signals, like intracellular Ca²⁺, have been shown to affect specific gene expression. To test how the gene expression landscape may differ between a synchronized islet population with its reproducible intracellular oscillations and an unsynchronized islet population with heterogeneous oscillations, gene set enrichment analysis (GSEA) was used to compare an islet population that had been synchronized using a glucose wave with a 5-min period, and an unsynchronized islet population. In the population exposed to the glucose wave, 58/62 islets showed synchronization as evidenced by coordinated intracellular Ca²⁺ oscillations with an average oscillation period of 5.1 min, while in the unsynchronized population 29/62 islets showed slow oscillations with an average period of 5.2 min. The synchronized islets also had a significantly smaller drift of their oscillation period during the experiment as compared to the unsynchronized population. GSEA indicated that the synchronized population had reduced expression of gene sets related to protein translation, protein turnover, energy expenditure, and insulin synthesis, while those that were related to maintenance of cell morphology were increased.     

Changes in gene expression in beta cells after islet isolation and transplantation using laser-capture microdissection

Aims/hypothesis The process of islet isolation can cause chemical and mechanical injury to beta cells. In addition, hyperglycaemia after islet transplantation can compromise beta cell function. The aim of this experiment was to evaluate changes in gene expression in endogenous islets using laser-capture microdissection (LCM). Materials and methods Islets from B6AF1 mice were studied in situ in the pancreas as well as those freshly isolated or cultured for 24 h. Fresh islets were transplanted under the kidney capsule of syngeneic diabetic (streptozocin-induced) and non-diabetic mice. Frozen sections from all the samples were prepared for LCM to obtain beta cell-enriched tissue; RNA was extracted and amplified using T7 polymerase. RT-PCR was used to assess expression of selected genes critical for beta cell function (Ins, Ipf1 [previously known as Pdx1], Slc2a2 [previously known as GLUT2] and Ldha) and the stress response (Hmox1 [previously known as HO-1], Gpx1, Tnfaip3 [previously known as A20] and Fas). Immunostaining was also performed. Results In freshly isolated and cultured islets, insulin and Ipf1 mRNA levels were decreased by 40% (compared with islets in situ), while stress genes were upregulated. Comparison between in situ pancreatic islets and engrafted beta cells of cured mice showed declines in Ipf1 expression. Conclusions/interpretation Our experiment, the first report to investigate changes in gene expression in endogenous islets using LCM, indicate that beta cells following islet isolation and residing in a foreign graft environment have decreased expression of genes involved in insulin production and increased expression of stress genes. Our data suggest that an islet graft, even in successful transplantation, may be different from endogenous islets in gene expression. Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible to authorised users.     

Comparison of gene expression profiles between primary tumor and metastatic lesions in gastric cancer patients using laser microdissection and cDNA microarray

INTRODUCTION Gastric cancer is one of the leading causes of cancer death in the world, its clinical behavior depends on the potential metastasis of the tumor, and the prognosis of advanced gastric cancers remains very poor. Until now, several molecules ha…     

肝癌相关基因表达的荧光定量PCR检测及分子诊断指数的建立

目的:研究肝细胞癌相关基因表达,建立肝癌分子诊断指数,以期能更准确的诊断肝癌.方法:采用实时荧光定量PCR检测40例肝细胞癌患者癌组织和配对的癌旁2 cm及手术切缘组织、10例肝硬化组织、10例正常肝脏组织中11个基因的表达,以管家基因G3PDH为对照,2-ΔΔCT法计算目的基因相对表达量,挑选出特异性好且与正常肝、肝...     

实时荧光定量PCR方法检测幼兔粪便双歧杆菌的实验研究

目的:应用实时荧光定量PCR技术对实验幼兔粪便内双歧杆菌进行定量分析．方法:依据双歧杆菌16S rDNA序列设计属特异性引物,以常规PCR产物经克隆后的质粒 DNA为标准品,经光谱定量、梯度稀释后制备标准曲线．抽提正常对照组和双歧杆菌喂饲组幼兔粪便内的细菌基因组DNA,用实时荧光定量PCR技术定量分析样品中双歧杆菌数量．结果:两组幼兔粪便内双歧杆菌测定结果均成阳性,双歧杆菌喂饲组0．05 g湿粪内菌量的对数值较对照组显著升高(6．37±0．58 vs 5．18 ±0．98,P=0．004)．结论:实时荧光定量PCR方法可正确定量实验兔粪便内双歧杆菌数量．     

实时相对定量反转录PCR检测小鼠阴道黏膜炎症因子的表达

目的建立实时相对定量反转录聚合酶链反应(real-time RQ RT-PCR)方法,能快速准确地检测各种炎症因子在阴道黏膜的转录表达情况,从而评价包括杀微生物剂在内的生殖道或直肠黏膜用候选药物的刺激毒性。方法以Eppendorf Mastercycler ep realplex实时荧光定量PCR仪为检测平台,选择小鼠β-actin基因为内参,建立基于SYBR GreenⅠ荧光染料的real-time PCR检测方法,对白介素2(Interleukin 2,IL-2)、IL-4、IL-6、IL-10、IL-17A、肿瘤坏死因子α(Tumor necrosis factorα,TNF-α)、γ干扰素(Interferonγ,IFN-γ)等炎症因子在生殖道黏膜的mRNA转录水平,同时进行检测,并用2-⊿⊿Ct方法计算实验组小鼠目的基因相对于空白组小鼠的表达差异情况。用微量样本多指标流式蛋白定量技术(Cytometric Bead Array,CBA)对结果进行验证。结果使用real-time RQRT-PCR能对小鼠阴道黏膜炎症因子的表达情况进行快速检测,结果与CBA检测结果相吻合。结论该方法快速、灵敏、特异性强、价格低廉、高通量。可用于杀微生物剂等生殖道或直肠黏膜用候选药物的临床前安全性评价工作。     

慢性浅表性胃炎不同证型与胃黏膜水通道蛋白3、4基因表达的相关性

目的:探讨慢性浅表性胃炎不同证型与胃黏膜水通道蛋白3、4基因表达的相关性.方法:胃镜下取胃体上部黏膜,液氮罐保存,荧光定量PCR法检测胃黏膜AQP3、AQP4的基因表达.结果:脾胃湿热证组AQP3、AQP4高于胃阴不足证组和正常人组(4.5980±0.8234 vs 3.4362±0.3450,3.8495±0.5072,7.7062±0.6859 vs 6.800±0.5544,7.0384±0.6706;P<0.051,脾虚湿困证组、寒湿困脾证组AQP3均高于胃阴不足证组(4.5158±0.5603,4.8083±0.8419 vs 3.4362±0.3450,P<0.05).脾胃湿热证组、脾虚湿困证组、寒湿困脾证组3组间AQP3、AQP4比较没有明显差异(P>0.05).胃阴不足证组和正常人组间AQP3、AQP4比较也没有明显差异(P>0.05).结论:慢性胃炎中医证型不同,胃黏膜AQP3、AQP4基因表达不同,胃黏膜AQP3、AQP4可能成为脾虚湿困、寒湿困脾、脾胃湿热、胃阴不足等病证的发生机制之一.