实时荧光定量-PCR和酶联免疫吸附法检测巨细胞病毒-IgM抗体的比较

目的:比较实时荧光定量-PCR和酶联免疫吸附法检测巨细胞病毒-IgM抗体水平的敏感性及准确率。方法:收集108例孕前筛查妇女,同时采用实时荧光定量-PCR和酶联免疫吸附法检测外周血巨细胞病毒-IgM抗体水平,并对这两种检测方法的阳性率进行比较。结果:实时荧光定量-PCR法阳性率为74%,酶联免疫吸附法为57%,两者差异有统计学意义(P<0.05);18例荧光定量-PCR法阳性的妇女血清巨细胞病毒-IgM拷贝数低于10-4/ml。结论:实时荧光定量-PCR与酶联免疫吸附法相比,对巨细胞病毒-IgM抗体检测具有较高的敏感性和准确率,值得临床推广使用。

沙门氏菌荧光实时定量PCR检测试剂的研制及应用

荧光实时定量PCR技术是近年来广泛应用于沙门氏菌快速检测的现代方法之一,本研究建立了检测沙门氏菌快速、敏感、特异以及准确定量的FQ-PCR方法。采用沙门氏菌fimY基因序列,设计特异引物和探针,通过对Taq酶、Mg2+和引物探针浓度等反应体系和条件的优化,然后进行特异性和适用性实验。最优化结果为:Taq酶用量2.5U;Mg2+浓度为3.75×10-3mol/L;引物浓度为0.65×10-6mol/L,探针浓度为0.30×10-6mol/L;循环条件为step1:95℃2min,step2:95℃5s,60℃40s,40cycles。结果表明该FQ-PCR检测试剂具有快速、简单、灵敏度高、特异性强和适用范围广等优点,可应用于食品卫生监管、商品检验检疫以及临床诊断等领域。

乙型肝炎病毒SYBR GreenⅠ实时荧光定量PCR方法的建立及临床应用

目的建立 SYBR Green I实时荧光定量 PCR检测乙型肝炎病毒 DNA的快速方法，并探讨其临床应用价值。方法根据GenBank公布的Hepatitis B virus gp1基因序列设计引物，建立SYBR Green I实时荧光定量PCR，并对反应体系和扩增程序进行优化。定量标准品通过基因克隆方法获得，同时以浙江省夸克公司 HBV DNA定量检测试剂盒作对照，应用于随机选取的100份乙型肝炎患者血清检测。结果 SYBR Green I 实时荧光定量 PCR 检出限范围为5＆#215;102 copies／ml～5＆#215;108 copies／ml，HBV DNA浓度与CT值有良好线性关系，无交叉反应，整个过程仅需2.5 h。在随机抽取的100份临床标本应用中，与浙江省夸克公司的 HBV荧光定量 PCR检测试剂相比，建立的 SYBR Green I实时荧光定量PCR体系灵敏度100％，特异度92.5％。结论 SYBR Green实时荧光定量PCR快速、简便、灵敏度高、特异度强，可用于乙型肝炎患者病情监测，有效指导临床用药，准确评价 HBV感染者的病情。

实时荧光定量PCR检测皱纹盘鲍Δ5脂肪酸去饱和酶基因表达方法的建立及应用

研究以皱纹盘鲍(Haliotis discus hannai Ino)体内存在的2条Δ5 Fad(Hdhfad1和Hdhfad2)为目的基因,β-肌动蛋白(β-actin)和核糖体蛋白S9(Ribosomal protein S9,RPS9)为内参基因,应用2–ΔΔCt方法建立了实时荧光定量PCR(Real-Time quantitative PCR,RT-qPCR)检测体系,并应用此体系分析了鲍鱼肌肉组织Δ5 Fad在不同饲料处理下的表达差异。实验饲料含有不同的脂肪源,分别是棕榈酸甘油酯(Tripalmitin,TP饲料)、富含二十碳四烯酸(Arachidonic acid,ARA)的油脂(AO饲料)和富含二十碳五烯酸(Eicosapentaenoic acid,EPA)的油脂(EO饲料)。结果表明:针对Hdhfad1、Hdhfad2、β-actin和RPS9所设计的引物特异性强。各引物对的PCR扩增效率(Efficiency,E)分别为1.05、0.99、0.97和0.98,满足2–ΔΔCt方法对E的要求。当退火温度为52℃,反应体积为25μL时,RT-qPCR的扩增效果最好。所建立的体系能够准确定量Δ5 Fad的基因表达。利用该方法分析Δ5 Fad在不同饲料处理下的表达结果显示,与TP对照组相比,EO和AO饲料显著降低了鲍鱼肌肉组织Δ5 Fad(Hdhfad1和Hdhfad2)的表达量。

鹿布鲁氏菌实时荧光定量PCR检测方法的建立

本研究依据布鲁氏菌的特异性基因Omp25c的部分片段作为靶基因,设计探针引物,且优化了反应体系,筛选出引物、探针的最优浓度配比。将扩增产物连接到PGEM-T载体上,制备标准品及标准曲线,建立鹿布鲁氏菌荧光定量PCR检测方法,并对其特异性、稳定性、敏感性进行评价。由标准曲线可知该方法的最低检测浓度可达到36拷贝/μL,比常规PCR灵敏度高出很多。

实时荧光定量PCR在EB病毒检测的临床应用

EB病毒在人群中广泛感染,中国3-5岁儿童EB病毒VCA-IgG抗体阳性率达90%以上,幼儿感染后多数无明显症状,或引起轻症咽炎和上呼吸道感染,青年期发生原发感染,约有50%出现传染性单核细胞增多症。主要通过唾液传播,也可经输血传染。EB病毒在口咽部上皮细胞内增值,然后感染B淋巴细胞,这些细胞大量进入血液循环而造成全身性感染。

牛奶子实时定量PCR分析中内参基因的评价与验证(英文)

【目的】实时定量PCR结果的精确性在很大程度上取决于选择的内参基因的稳定性。通过评估候选管家基因的表达稳定性,筛选出用于牛奶子研究的最佳内参基因。【方法】设计简并引物从牛奶子中克隆12个潜在的内参基因片段,包括14-3-3、18S核糖体RNA(18SrRNA)、β-actin(Actin)、延长因子1-α(EF1-α)、真核起始因子4A(e IF4A)、3-磷酸甘油醛脱氢酶(GAPDH)、RNA聚合酶-Ⅱ(RPⅡ)、60S核糖体蛋白(RPL7)、翻译延长因子2(TEF2)、泛素连接酶E2(UBCE)、泛素(UBQ)和泛素延伸蛋白5(UBQ5)。采集牛奶子5个不同器官(根、茎、叶、花和红果)、4个成熟期的果实(绿果、黄果、深粉果和完全成熟的红果)、2种激素(脱落酸、赤霉素)处理4个时间点的绿果、热处理4个时间点的离体叶片、幼苗盐胁迫2个时间点的根茎叶,应用实时荧光定量PCR技术检测12个内参基因在各样品中的表达情况,采用基于CT值的ge Norm、Normfinder和Best Keeper及CT比较4种算法评价这些内参基因的稳定性,最终的排名则由Ref Finder算法产生。【结果】器官组稳定性好的前2位内参基因为UBCE和RPL7,果实成熟期组排名前2的为e IF4A和UBCE,激素处理组排名前2的为e IF4A和UBCE,非生物胁迫组排名前2的则为Actin和EF1-α,综合分析所有样品排名前3位的是e IF4A、RPL7和UBCE。分别用筛选出的稳定的e IF4A、RPL7、UBCE和不稳定的RPⅡ作为内参基因评价目的基因八氢番茄红素合成酶基因Eut Psy在果实成熟过程中的表达,结果显示分别以3个稳定的内参基因为单内参基因与以e IF4A同UBCE组合做内参基因所得到的结论一致,而RPⅡ给出的则不同。【结论】在应用荧光实时定量PCR技术研究牛奶子基因转录表达时,通常情况下e IF4A、RPL7和UBCE相对于其他9个候选内参基因更为可靠。研究结果为牛奶子及胡颓子属其他物种的基因表达分析奠定基础。

实时荧光定量PCR在食品致病菌及转基因成分检测中应用

与传统定性PCR技术相比,实时荧光定量PCR有更多的优点,其速度快,特异性更强、灵敏度更高、无污染性、自动化水平高等,且能对DNA模板进行定量。本文综述了实时荧光定量PCR技术原理、分类及其应用,并对其存在的问题和发展前景进行了展望。

应用Q-PCR定性检测KIR基因有无方法的建立

目的建立定性检测KIR基因有无的Q-PCR方法。方法根据高分辨水平中国人群KIR等位基因的多态性,并参考国际IPD-KIR数据库,针对16种KIR基因及2DS4-Normal、2DS4-Deleted两种亚型,设计KIR基因特异性引物用于Q-PCR扩增反应;同时设置一孔阴性对照、一孔阳性对照(特异性扩增人体生长激素HGH基因片段),以监控假阳性、假阴性的结果。为验证Q-PCR方法的可靠性,随机选择302份已采用KIR PCR-SSP商品化试剂盒检测的标本,采用Q-PCR方法盲检和对比。结果300人份的Q-PCR检测结果与已知的PCR-SSP检测结果相符,有2份标本结果不一致,其中1例标本的2DS5基因Q-PCR检测结果为阴性,而PCR-SSP检测结果为阳性;另一例标本2DS1基因Q-PCR检测结果为阳性,而PCR-SSP检测结果为阴性。对2份标本分别进行2DS5、2DS1基因测序分型,证实Q-PCR定性检测结果正确。结论本文建立的KIR Q-PCR方法结果准确、可靠,可用于KIR基因有无的定性检测。

Detection of Survivin mRNA in nasopharyngeal carcinoma by real-time fluorescence quantitative RT-PCR

Objective： To establish the method of real time fluorescence quantitative RT-PCR for detecting the expression of Survivin mRNA in nasopharyngeat carcinoma （NPC） tissues. Methods： The total RNA was extracted from NPC cell line CNE-2 and tissues with Trizol and then been transcribed reversely to cDNA, a method of real time fluorescence quantitative RT-PCR for detecting the expression of Survivin mRNA in NPC tissues had been established, in which chronic nasopharyn-gitis patients＇ nasopharynx tissues treated as control group. Results： The expression of Survivin mRNA all could be detected either in CNE-2 cells, NPC tissues or in chronic nasopharyngitis patients＇ nasopharynx tissues, and there was higher the expression level of Survivin mRNA in NPC tissues than which in chronic nasopharyngitis patients＇ nasopharynx tissues, the difference was significant （P 〈 0.01）. The expression of Survivin mRNA could be detected both in stage Ⅰ ＋ Ⅱ and stage Ⅲ ＋ Ⅳ NPC, and there was no significant difference in relative quantifications of gene expression between these two groups （P 〉 0.05）. There was no relationship between Survivin mRNA expression and age and sex of NPC patients （P 〉 0.05）. Conclusion： Real time fluorescence quantitative RT-PCR is a rapid, effective and high sensitive method for detecting the expression of Survivin mRNA in NPC tissues. The overexpression of Survivin mRNA may play some roles in pathogenesis of NPC.

Detection of Syndecan-1 and Heparanase-1 Genes in Esophageal Carcinoma by Quantitative RT-PCR

OBJECTIVE To quantitatively explore the expression of Syndecan-1 and heparanase-1 in esophageal cancer tissue as well as their relationship with the clinicopathological factors, in order to evaluate their roles in tumor invasion and metastasis.METHODS Real-time fluorescence quantitative PCR （Q-PCR） was used to analyze the expression levels of Syndecan-1 and heparanase-1 genes￡？participants included 67 cases with esophageal cancers and 32 healthy volunteers.RESULTS The expression of Heparanase-1 gene in esophageal cancers was higher than that in normal esophageal tissue （P 〈 0.001）, and the expression of Syndecan-1 gene in the normal esophageal tissue was higher compared with esophageal cancers （P 〈 0.001）. The positive rates of Syndecan-1 and Heparanase-1 gene in esophageal cancer were 13.4% （9/67） and 85.1% （57/67）.The expression of Syndecan-1 and Heparanase-1 genes was signifi cantly related to di. erentiation, depth of infi ltration, lymph node metastasis, vessel metastasis, and TNM stages of disease （P 〈 0.05）. In an attempt to measure the association between the 2 agents, this study found that the expression of Syndecan-1 mRNA had a significantly negative correlation with the expression of Heparanase-1 mRNA by using Spearman rank correlation test （OR = -0.572, P 〈 0.001）.CONCLUSION Syndecan-1 and Heparanase-1 play important roles in the invasion and metastasis of esophageal cancer. The reduction of Syndecan-1 and/or the increase of Heparanase-1 may influence the invasion and metastasis of malignant tumors.Thus the combination assay of Syndecan-1 and Heparanase-1 may contribute to the diagnosis and treatment of malignant tumors.

Identification of normalization factors for quantitative realtime RT-PCR analysis of gene expression in Pacific abalone Haliotis discus hannai

Quantitative real-time reverse transcription-polymerase chain reaction （qRT-PCR） is widely used in studies of gene expression. In most of these studies, housekeeping genes are used as internal references without validation. To identify appropriate reference genes for qRT-PCR in Pacific abalone Haliotis discus hannai, we examined the transcription stability of six housekeeping genes in abalone tissues in the presence and absence of bacterial infection. For this purpose, abalone were infected with the bacterial pathogen Fibrio anguillarum for 12 h and 48 h. The mRNA levels of the housekeeping genes in five tissues （digestive glands, foot muscle, gill, hemocyte, and mantle） were determined by qRT-PCR. The PCR data was subsequently analyzed with the geNorm and NormFinder algorithms. The results show that in the absence of bacterial infection, elongation factor-l-alpha and beta-actin were the most stably expressed genes in all tissues, and thus are suitable as cross-tissue type normalization factors. However, we did not identify any universal reference genes post infection because the most stable genes varied between tissue types. Furthermore, for most tissues, the optimal reference genes identified by both algorithms at 12 h and 48 h post-infection differed. These results indicate that bacterial infection induced significant changes in the expression of abalone housekeeping genes in a manner that is dependent on tissue type and duration of infection. As a result, different normalization factors must be used for different tissues at different infection points.

Evaluation of Sensitivities and Specificities of SARS-CoV Detection by Real-time Quantitative Reverse Transcription-PCR Assays

The etiological agent of severe acute respiratory syndrome(SARS) was identified as a new coronavirus,termed SARS-CoV. Establishment of an efficient and sensitive diagnostic system of SARS-CoV genetic materials is crucial for SARS control. In this study,we quantified SARS-CoV mRNAs in both infected cell culture lysate and in supernatant by using Real-time quantitative revere transcription-PCR based on EvaGreenTM dye and Taqman-MGB probes. For extensive evaluation of sensitivities and specificities,13 pairs of primers and 4 probes were designed based on different genes of SARS-CoV. Glyceraldehydes-3-phosphate dehydrogenase(GAPDH) was selected as the internal control gene. Results showed that S-gene-specific PCR was the most sensitive for detection,but because of its sequence variability in the different viral strains,primers and a probe based on the N gene were suitable substitutions. Meanwhile,we found the mRNA concentrations in cell culture lysates were much higher than in cell supernatant and facilited more sensitive detection of the SARS-CoV.

From Phenotypes to Molecules: Revolutionizing Gut Microbiota Identification Methods

The gut microbiota is a complex ecosystem composed of many bacteria and their metabolites.It plays an irreplaceable role in human digestion,nutrient absorption,energy supply,fat metabolism,immune regulation,and many other aspects.Exploring the structure and function of the gut microbiota,as well as their key genes and metabolites,will enable the early diagnosis and auxiliary diagnosis of diseases,new treatment methods,better effects of drug treatments,and better guidance in the use of antibiotics.The identification of gut microbiota plays an important role in clinical diagnosis and treatment,as well as in drug research and development.Therefore,it is necessary to conduct a comprehensive review of this rapidly evolving topic.Traditional identification methods cannot comprehensively capture the diversity of gut microbiota.Currently,with the rapid development of molecular biology,the classification and identification methods for gut microbiota have evolved from the initial phenotypic and chemical identification to identification at the molecular level.This review integrates the main methods of gut microbiota identification and evaluates their application.We pay special attention to the research progress on molecular biological methods and focus on the application of high-throughput sequencing technology in the identification of gut microbiota.This revolutionary method for intestinal flora identification heralds a new chapter in our understanding of the microbial world.

Notch1在GES-1和其他胃癌细胞中表达差异性的比较

目的探讨Notch 1在GES-1、AGS、SGC-7901和BGC-823中的表达差异性。方法采用real time RT-PCR技术和Western blot方法研究Notch 1在GES-1、AGS、SGC-7901和BGC-823细胞mRNA和蛋白质水平上的表达。结果与GES-1相比较,Notch 1 mRNA和NOTCH 1蛋白在AGS,SGC-7901和BGC-823中表达显著降低,差异均具有显著性(P<0.01)。结论Notch 1在胃癌的发生中可能作为抑癌基因起作用。

B细胞激活因子在支气管哮喘患者中的变化及意义

目的:探讨B细胞激活因子(Bcell activating factor,BAFF)在支气管哮喘发病中的作用。方法:采用酶联免疫吸附测定法检测31例健康成人(对照组)和43例哮喘急性发作期和缓解期患者治疗前后血清BAFF水平,采用实时定量-PCR法检测外周血单个核细胞(peripheral blood mononuclear cells,PBMCs)BAFFmRNA表达水平。计量资料血清BAFF水平和BAFFmRNA呈非正态分布,以中位数(最小值～最大值)表示,应用Kruskal-Wallis法比较3组间BAFF水平的差异,采用Mann-WhitneyU检验作两两比较。采用Pearson相关分析进行相关性检验。结果:血清BAFF水平和PBMCs BAFF mRNA表达水平在急性发作期患者高于缓解期患者和对照组,差异具有统计学意义(P<0.05),缓解期患者与对照组相比,差异无统计学意义(P>0.05);急性发作期和缓解期哮喘患者血清BAFF水平和PBMCs BAFF mRNA表达水平呈正相关(分别r=0.456,P<0.05和r=0.523,P<0.05)。结论:血清BAFF水平和PBMCs BAFF mRNA表达水平在急性发作期哮喘患者明显增高,其动态变化与病情变化有关。

Developmental Changes of the FAS and HSL mRNA Expression and Their Effects on the Content of Intramuscular Fat in Kazak and Xinjiang Sheep

Twenty-four male Kazak sheep and 30 Xinjiang fine wool sheep at different ages were selected to investigate the development-dependent expression levels of fatty acid synthase （FAS） gene and hormone-sensitive lipase （HSL） gene in muscle and their effects on the contents of intramuscular fat （IMF）. Longissimus dorsal muscle was sampled to measure IMF and total RNA was extracted to determine FAS and HSL mRNA expression levels by real-time PCR. The results showed that： l） The IMF content increased continuously with growth and showed significant differences （P 〈 0.05） between different age groups in male Kazak sheep, but in Xinjiang fine wool sheep there was no such difference observed. Furthermore, the IMF contents in Kazak were much higher （P 〈 0.01） than that of the other breed from day 30 to 90. 2） FAS mRNA expression level was the highest （P 〈 0.05） on day 0 in Kazak sheep and then declined with growth, in the other breed the gene showed a d‘ecline-rise-decline-rise＇ expression manner as the animals grew. HSL mRNA expression level had a similar model in two breeds, in Kazak sheep it was the highest on day 0 （P 〈 0.05） and in Xinjiang fine wool sheep on day 30 （P 〈 0.01）, then both decreased after this term. 3） In male Kazak sheep, FAS and HSL mRNA expression level were both negatively related to IMF content （r= -0.485 （P = 0.02）, r= -0.423 （P = 0.05））, and the ratio of FAS/HSL expression exhibited significantly negatively related IMF contents. In male Xinjiang sheep, there were no obvious relationship between FAS and HSL expression and IMF content （P 〉 0.05）.

Selection of Reference Genes in Transcription Analysis of Gene Expression of the Mandarin Fish, Siniperca chuasti

At present, transcription analysis of gene expression commonly uses housekeeping genes as control for normalization. In this study, the expression levels of three housekeeping genes including GAPDH, β-actin, and 18S rRNA in six tissues and five developmental stages of the Mandarin fish Siniperca chuatsi were assayed with quantitative real-time PCR （qPCR）. Differences in expression levels were analyzed using geNorm program. The results demonstrate that β-actin is the most stable gene at developmental stages and GAPDH is the most stable in different tissues. While 18S rRNA expression during development is differentially regulated, which indicates it is suitable as an internal control for gene expression normalization at the developmental level. Overall, the data suggest that the two most stable housekeeping genes are enough to accurately calibrate gene expression in S. chuatsi. The significance of this study provided convincing references and methodology for housekeeping gene selection and normalization in gene expression analysis with regular PCR or qPCR.

肺癌组织中Cyr61基因表达及临床意义

目的:研究人肺癌组织中Cyr61基因表达的临床意义。方法:采用实时荧光定量-PCR技术和免疫组织化学染色法对60名肺癌患者的肺癌组织和癌旁肺组织的Cyr61 mRNA和蛋白表达水平进行测量。结果:80%(48/60)肺癌患者的癌组织中Cyr61表达水平低于其配对的癌旁肺组织中的水平,与免疫组织化学染色法测定的结果相一致。统计分析显示,两组间差异有统计学意义(2.742±4.165vs4.933±3.349,t=-5.112,P=0.000)。肿瘤恶性程度分级、淋巴结转移、病理学类型、吸烟状况及家族史等临床参数均可影响癌组织中的Cyr61的表达水平(P<0.05)。结论:Cyr61对肺癌的进展起重要作用,因此Cyr61表达的蛋白产物可作为临床诊断的重要指标。

莪术醇对人卵巢癌SKOV3细胞株JAK2/STAT3信号通路影响的研究

目的观察莪术醇对人卵巢癌SKOV3细胞株体外生长的影响及对SKOV3细胞株JAK2/STAT3信号通路基因表达的影响,探讨莪术醇治疗卵巢癌的分子机制。方法不同浓度莪术醇作用于人卵巢癌细胞株SKOV3,MTT法检测SKOV3细胞的增殖抑制率,实时荧光定量-PCR法检测SKOV3细胞中JAK2、STAT3基因表达水平。结果莪术醇对卵巢癌SKOV3细胞有明显的增殖抑制作用,其强度随药物作用时间及浓度的增加而增强,呈时间-剂量依赖性。实时荧光定量-PCR法检测证实莪术醇作用后SKOV3细胞中JAK2、STAT3基因表达受到明显抑制。结论莪术醇能明显抑制SKOV3细胞的体外增殖,诱导细胞凋亡,其机制可能是通过降调节JAK2、STAT3基因的表达来实现的。