Duplex PCR快速检测松材线虫

利用duplexPCR技术对松材线虫 (Bursaphelenchusxylophilus)与拟松材线虫 (B .mu cronatus)的rDNA部分核苷酸序列扩增。根据松材线虫与拟松材线虫的ITS1序列区别 ,设计出特异性引物 ,检测松材线虫的存在 ;在 5 8S ,2 8S保守序列区设计通用引物 。

鉴别猪圆环病毒2型和3型双重TaqMan MGB探针FQ-PCR检测方法研究

建立一种快速、特异鉴别检测猪圆环病毒2型(PCV2)和猪圆环病毒3型(PCV3)的双重TaqMan MGB探针FQ-PCR方法,本研究以PCV2的Rep蛋白和PCV3的Cap蛋白基因作为靶基因,各设计1对特异性引物和1条TaqMan MGB探针,经优化各反应条件和进行敏感性、特异性、重复性和干扰性试验,建立鉴别检测PCV2/PCV3的双重FQ-PCR方法。结果显示:该方法可特异性扩增PCV2、PCV3核酸,与猪伪狂犬病病毒(PRV)等8种病原及阴性对照无交叉反应,特异性较强;对PCV2和PCV3阳性质粒标准品的最低检出限均可达10 copies/μL,敏感性较高;PCV2/PCV3批内/批间重复试验变异系数(CV)值均在3%以下,表明方法稳定性、重复性较好;干扰性试验表明在两种病毒阳性质粒起始模板相差较大时该方法不会影响对其中任一病毒核酸的检出和准确定量。对42份临床疑似PCV感染样品检测结果与PCV2、PCV3基因测序结果符合率100%。本研究建立的双重FQ-PCR方法具有敏感性高达10 copies/μL、特异性强、在同一反应体系中能同时快速鉴别检测PCV2、PCV3等优点,可用于临床PCV2/PCV3感染的快速鉴别检测。

基于二重实时荧光PCR方法精准快速鉴定大豆转基因种子转化体纯度

【目的】耐除草剂大豆SHZD3201、DBN9004、中黄6106(ZH10-6)相继获得生产应用安全证书,针对这3个转化体建立二重实时荧光PCR检测方法,应用于大豆转基因转化体种子纯度的精准、快速鉴定,为大豆转基因品种种子质量安全监管提供技术支撑。【方法】搜集耐除草剂大豆SHZD3201、DBN9004和中黄6106 3个转化体以及4个大豆内标准基因Lectin的实时荧光PCR方法,通过比较ΔCt值,遴选出二重实时荧光PCR的最佳大豆内标准基因检测方法;设置转化体和Lectin不同引物/探针浓度,优化二重实时荧光PCR的反应体系;根据不同类型的特异性测试样品测试二重实时荧光PCR方法的特异性;设置2 000、200、20、10、5和1拷贝的梯度样品,测试方法的检出限。利用一步提取液快速研磨单粒种子,以稀释后的粗提液直接作为模板进行二重实时荧光PCR扩增,进而开展耐除草剂大豆SHZD3201、DBN9004和中黄6106单粒种子纯度的检测。【结果】经测试计算最小ΔCt值,在SHZD3201、DBN9004和中黄6106转化体二重实时荧光PCR中,遴选出最佳大豆内标准基因Lectin检测方法。经优化,SHZD3201/Lectin二重实时荧光PCR反应体系中,SHZD3201转化体的引物/探针浓度为0.3μmol·L^(-1)/0.15μmol·L^(-1),Lectin的引物/探针浓度为0.3μmol·L^(-1)/0.15μmol·L^(-1);DBN9004/Lectin二重实时荧光PCR反应体系中,DBN9004转化体的引物/探针浓度为0.4μmol·L^(-1)/0.2μmol·L^(-1),Lectin的引物/探针浓度为0.4μmol·L^(-1)/0.2μmol·L^(-1);中黄6106/Lectin二重实时荧光PCR反应体系中,中黄6106转化体的引物/探针浓度为0.4μmol·L^(-1)/0.2μmol·L^(-1),Lectin的引物/探针浓度为0.5μmol·L^(-1)/0.25μmol·L^(-1)。3种方法特异性良好,检出限均达10个拷贝。利用100粒模拟单粒种子样本,快速研磨,模板稀释5倍后,采用二重实时荧光PCR快速扩增,成功地检测了SHZD3201、DBN9004和中黄6106种子转化体纯度。【结论】成功建立了耐除草剂大豆SHZD3201/Lectin、DBN9004/Lectin和中黄6106/Lectin的二重实时荧光PCR方法,结合一步提取液的DNA快速提取方法,实现了大豆转基因种子转化体纯度精准快速检测。

Identification of Orientia tsutsugamushi,spotted fever group and typhus group Rickettsia by duplex and nested PCR methods

Objective:To identify members of genera of rickettsia and O.tsutsugammhi simultaneously.Methods:Rapid and duplex and nested PCR methods have been established by designing primers based on the conserved regions of heat shock protein GroEL gene.345 mouse viscera samples including liver,spleen and kidney,96 Xenopsylla cheopis and 32 chiggers collected from Hongta areas of Yuxi city,Yunnan province were tested by the new PCR methods.Results:The result of the study showed that the new PCR methods could identify most members of genera -Rickettsia and Orientia simultaneously with 100%specificity and its sensitivity could test one copy per microliter.The results of detection prevalence of rickettsioses in mouse,flea and mites DNA samples showed that the total rickettsia infection rate in mouse was 34.78%(120/345).The total infection rates in R.typhi,O.t Karp and R.sibirica of mouse samples were 28.12%(97/345),19.71%(68/345) and O. 29%(1/345) respectively.Co-infection rates in R.typhi and 0.t Karp of mouse samples were 13.33%(46/ 345).O.t Karp type has been the main epidemic strain in these areas.Conclusion:We concluded that this PCR method could be used to detect multi-genera rickettsia simultaneously.Molecular evidences provided in this and previous studies strongly support that Hongta areas of Yuxi city are a natural focus for typhus and scrub typhus with the common occurrence of their confection.

A duplex PCR for the rapid and simultaneous detection of Brucella spp.in human blood samples

Objective:To design a duplex PCR for rapid and simultaneous detection of Brucella species, in human blood samples.Methods:Fifty-two peripheral bloods samples were collected from suspicious patients with brucellosis.Following DNA extraction,PCR assay were performed, using three primers that could simultaneously identify and differentiate three major species of pathogenic Brucella in humans and animals.Results:Of the 52 peripheral bloods samples tested, 25 sample(48%) showed positive reactions in PCR.Twelve samples were positive for Brucella abortus(B.abortus)(23%,13 for Brucella melUensis(B.melUensis)(25%) and 0 for Brucella ovis (6.ovis)(Ow.Conclusions:This work de=monstrates dial in case where specific primers were utilized,duplex PCR has proved to be a simple,fast,and relatively inexpensive method for simultaneous detection of important species of Brucella in clinical samples.

One-Step Multiplex PCR for Simultaneous Detection and Identification of Eight Medically Important <i>Candida</i>Species

Recently, the incidence of Candida infections has substantially increased. Conventional identification methods for Candida species are technically difficult to conduct and cannot accurately distinguish each species. The purpose of the present study was to design primers to identify and detect simultaneously eight medically important Candida species using one-step multiplex PCR. PCR primers were designed based on partial sequences of intergenic spacer (IGS) and internal transcribed spacer (ITS) genes of eight medically important Candida species. These primers were able to distinguish each Candida species and did not display cross-reactivity with representative Candida species other than the eight Candida species. Moreover, our developed one-step multiplex PCR method is accurate, specific, cost-effective, time-saving, and worked without requiring DNA extraction.

A duplex RT-PCR assay for detection of H9 subtype avian influenza viruses and infectious bronchitis viruses

H9 s ubtype avian influenza virus（AIV） and infectious bronchitis virus（IBV） are major pathogens circulating in poultry and have resulted in great economic losses due to respiratory disease and reduced egg production. As similar symptoms are elicited by the two pathogens, it is difficult for their differential diagnosis. So far, no reverse transcription-polymerase chain reaction（RT-PCR） assay has been found to differentiate between H9 AIV and IBV in one reaction. Therefore, developing a sensitive and specific method is of importance to simultaneously detect and differentiate H9 AIV and IBV. In this study, a duplex RT-PCR（d RT-PCR） was established. Two primer sets target the hemagglutinin（HA） gene of H9 AIV and the nucleocapsid（N） gene of IBV, respectively. Spec ific PCR products were obtained from all tested H9 AIVs and IBVs belonging to the major clades circulating in China, but not from AIVs of other subtypes or other infectious avian viruses. The sensitivity of the d RT-PCR assay corresponding to H9 AIV, IBV and mixture of H9 AIV and IBV were at a concentration of 1×10^1, 1.5×10^1 and 1.5×10^1 50% egg infective doses（EID_（50）） m L^–1, respectively. The concordance rates between the d RT-PCR and virus isolation were 99.1 and 98.2%, respectively, for detection of samples from H9N2 AIV or IBV infected chickens, while the concordance rate was 99.1% for detection of samples from H9N2 AIV and IBV co-infected chickens. Thus, the d RT-PCR assay reported herein is specific and sensitive, and suitable for the differential diagnosis of clinical infections and survei llance of H9 AIVs and IBVs.

肺炎克雷伯菌与链球菌双重PCR检测方法的构建

【目的】旨在建立一种可同时检测肺炎克雷伯菌和链球菌的双重PCR检测方法。【方法】选取肺炎克雷伯菌KP-Khe基因和链球菌EF-Tu基因保守片段,分别合成2对特异性引物,优化双重PCR反应体系,摸索其特异性、最佳退火温度、引物浓度和细菌核酸浓度,并通过该方法对临床样品进行检测验证。【结果】该双重PCR检测方法可有效扩增出肺炎克雷伯菌和链球菌的489bp和197bp的特异性片段,最适退火温度为58℃、最适引物浓度为12ng/µL、最适模板浓度为3ng/µL。将该方法应用于临床对15份样品进行检测,其中2份样品检测出肺炎克雷伯菌呈阳性,1份样品检测出链球菌呈阳性,与分离鉴定结果一致。【结论】该研究建立的双重PCR技术,可为临床诊断肺炎克雷伯菌、链球菌及混合感染提供了一种便捷高效的检测方法,具有一定的应用价值。

猫冠状病毒和猫细小病毒双重荧光定量PCR方法的建立

为建立猫冠状病毒(feline coronavirus,FCoV)和猫细小病毒(feline parvovirus,FPV)的双重荧光定量PCR方法,选取FCoV 3'UTR和FPV VP2基因保守区域,分别设计2对特异性引物和TaqMan MGB探针,并进行反应体系和条件优化,以及特异性、敏感性和重复性试验,探讨所建方法的可行性。结果显示:该方法可特异性检出FCoV和FPV,与猫疱疹病毒、猫杯状病毒、猫轮状病毒、支原体、衣原体、波氏杆菌、犬腺病毒和犬副流感病毒等病原核酸无交叉反应,对FCoV和FPV检测限均为1 copies/μL;FCoV和FPV阳性参考质粒组间和组内重复试验变异系数均小于3%;对35份临床样本进行检测,发现建立的双重荧光定量PCR方法阳性检出率比普通PCR方法高。结果表明,本研究建立的双重荧光定量PCR方法具有灵敏、特异和稳定等优点,可用于临床FCoV和FPV感染的早期鉴别诊断。

Development of a Duplex Real-Time PCR Method for the Pharmaceutical Rapid Microbial Detection of <i>Staphylococcus aureus</i>and <i>Pseudomonas aeruginosa</i>

Objective: To develop a duplex real-time PCR assay for pharmaceutical rapid microbial detection of Staphylococcus aureus and Pseudomonas aeruginosa. Methods: The specific primers and probes were designed to amplify the femB gene of S. aureus and the DNA gyrase subunit B gene of P. aeruginosa. The sensitivity of the system was detected by a multiple proportional dilution method. In order to examine the specificity of the system, other twenty-one bacteria strains were assayed simultaneously. Results: A highly sensitive and specific duplex real-time PCR assay for the detection of S. aureus and P. aeruginosa was established. The sensitivity was 50 copies/μL. The specificity was 100%. The whole detection procedure can be finished within 2.5 h. Conclusion: The duplex real-time PCR method is efficient in detecting with good sensitivity and specificity. There is a good prospect of this method applying in disease prevention and pharmaceutical industry due to the simultaneous detection of two pathogens.

非洲猪瘟病毒、高致病性猪繁殖与呼吸综合征病毒二重实时荧光定量PCR检测方法的建立与初步应用

建立一种特异、敏感、快速的实时荧光定量PCR(FQ-PCR)方法,用于非洲猪瘟病毒(ASFV)和高致病性猪繁殖与呼吸综合征病毒(HP-PRRSV)的鉴别诊断。针对ASFV的B646L基因和HP-PRRSV的NSP2基因分别设计特异性引物/探针对,经优化反应体系、反应程序等反应条件,建立一种基于探针技术的FQ-PCR方法,验证方法的敏感性、特异性和重复性,对130份临床样品进行检测,并与OIE检测方法(ASFV)及国标方法(HP-PRRSV)进行比较分析。本研究成功建立的ASFV和HP-PRRSV二重FQ-PCR检测方法在10^(-1)~10^(5) copies/μL模板范围内有良好的线性关系;对ASFV和HP-PRRSV基因出现阳性扩增,但对猪日本乙型脑炎病毒(JEV)、猪瘟(CSFV)、猪细小病毒(PPV)、猪伪狂犬病病毒(PRV)、猪圆环病毒2型(PCV2)、猪繁殖与呼吸综合征病毒(PRRSV)美洲经典株(VR2332株)、健康猪脾脏等7种病原核酸样品对照未出现扩增;批内、批间试验变异系数在0.53%~3.14%,重复性良好;对ASFV和HP-PRRSV的最低检测模板浓度均为10 copies/μL;利用建立的二重FQ-PCR方法对130份临床样品进行检测,检测结果与OIE检测方法(ASFV)及国标方法(HP-PRRSV)完全一致。本研究成功建立了鉴别ASFV和HPPRRSV二重FQ-PCR检测方法,为ASFV和HP-PRRSV的鉴别诊断提供了快速、敏感、特异且能满足临床检测需求的检测方法。

Development of a Duplex Real-time PCR assay for Detection of Perkinsus and Marteilia refringens in Shellfish

[ Objective] To improve the accuracy and efficiency of the detection which used in Perkinsus sp and Marteilia refringens, and then short- en the detective cycle. [ Method] According to the gene sequence of Perkinsus sp and Marteilia refringens from gene bank, design two pairs of spe- cific primers and two TaqMan probes with different fluorophores labeled. Optimizing the reactive conditions and reagent concentration in order that establishing the duplex real-time PCR method for detecting Perkinsus sp and Marteilia refringens simultaneously. [ Result ] The sensitivity of the du- plex real-time PCR method which about Pertdnsus sp and Marteilia refringens is 40 template copies. After combine the templates of Perkinsus sp and Marteilia refringens with different concentrations, this method still could be detect this two protozoan efficiently and synchronously. [ Condudon] The es- tablished duplex real-time PCR method for detecting Perkinsus sp. and Marteilia refringens possesses lots of advantages, such as specific, sensitive, rapid, quantitative and reproducible, can be used for clinical detection of infection which was caused by Perkinsus sp. and Marteilia refringens.

非洲马瘟病毒和西尼罗病毒双重TaqMan荧光定量RT-PCR检测方法的建立及应用

本研究旨在建立一种可同时检测非洲马瘟病毒(African horse sickness virus,AHSV)和西尼罗病毒(West Nile virus,WNV)的双重荧光定量RT-PCR检测方法。根据AHSV VP 7基因序列和WNV Poly Protein基因的高度保守区域设计特异性引物和探针,优化反应条件及体系,绘制标准曲线,对其特异性、敏感性和重复性进行测定,并采用该方法对临床样品进行检测验证。结果显示:该方法能够同时检测AHSV和WNV,且特异性良好,与马动脉炎病毒、马疱疹病毒1型、马传染性贫血病毒、马腺疫链球菌、马流感病毒等马病核酸均无交叉反应;敏感性高,AHSV和WNV最低检测限均为10 copies·μL^(-1);组内变异系数为0.04%~0.93%,组间变异系数为0.17%~4.83%,重复性良好;使用该方法对30份马全血样品进行检测,结果均为阴性。本试验建立的检测方法对马属动物检疫、非洲马瘟和西尼罗热的监测与防控具有重要意义。

Duplex PCR Detection of Pseudomonas savastanoi pv.phaseolicola and Curtobacterium flaccumfaciens pv,flaccumfaciens in Soybean

The paper aimed to establish a duplex PCR method for simultaneous detection of Pseudomonas savastanoi pv. Phaseolicola （Psp） and Curtobaeterium /accumfadens pv. Flaccumfaciens （Cff）. Based on the argK gene of Psp in GenBank, the primers PSPF1/PSPR2 were designed. The duplex PCR assay was dereloped using the combined primers PSPF1/PSPR2 and CflF1/CffR2, which were specific primers for Cff. The reaction conditions were optimized and specificity md sensitivity of the duplex PCR were tested. The expected DNA fragment was specifically amplified from the genomic DNA of Psp and Cff. Specificity was conirmed in the artificially inoculated soybean samples imparted. Thus, the duplex PCR developed in this study could be used for the simultaneous detection of Psp md Cff from imported soybean.

双重PCR区分检测花生黑腐病菌和花生基腐病菌

黑腐病和基腐病是威胁花生生产的重要病害。两种病害在田间发病症状十分相似,凭症状区分诊断困难。本研究利用calmodulin(cmdA)基因序列设计特异性引物,通过优化反应体系和反应条件,针对花生黑腐病菌和基腐病菌进行了双重PCR的区分检测。结果表明,在反应体系浓度为1.8×、引物浓度为0.2μmol/L、退火温度为62℃、反应循环数为37的条件下,可特异性地分别扩增出两条目的条带(274 bp和409 bp),检测灵敏限度为100 pg/μL。成功建立了可准确、快速区分检测花生黑腐病菌和花生基腐病菌的双重PCR,可为准确诊断和及时防控花生两种易混淆的病害提供科学的参考。

Establishment and Preliminary Application of One-step Reverse Transcriptase Droplet Digital PCR Assay for Bovine Viral Diarrhea Virus

[Objective]The paper was to establish a one-step reverse transcriptase droplet digital PCR(RT-ddPCR)assay for bovine viral diarrhea virus(BVDV).[Method]Based on one-step real-time quantitative PCR(RT-qPCR)assay,BVDV-specific primers and probes were designed in this study.The reverse transcriptase,annealing temperature,primer and probe concentrations and reaction conditions of RT-ddPCR assay were optimized.Meantime,the specificity,sensitivity and repeatability of RT-ddPCR assay were evaluated.[Result]The optimal reverse transcription system for the established RT-ddPCR assay was as follows:commercial one-step reverse transcriptase droplet digital PCR kit with matching reagents,a final primer concentration of 900 nmol/L,a final probe concentration of 250 nmol/L and an optimal annealing temperature of 57℃.The results were negative when the method was used to detect other common epidemic viruses;the minimum detection limit was 3.2 copies/μL with good repeatability,and the coefficient of variation was less than 5%.RT-ddPCR and RT-qPCR assays were used to test 24 bovine swab samples and the test results showed that the established RT-ddPCR assay was superior to RT-qPCR assay.[Conclusion]The RT-ddPCR assay established in this study has strong specificity,high sensitivity and good repeatability,and is suitable for nucleic acid detection of clinical samples.This study provided a technical support for early detection and quantitative diagnosis of BVDV infection.

O型口蹄疫病毒和塞内卡病毒双重荧光定量RT-PCR检测方法的建立

为建立O型口蹄疫病毒(FMDV-O)和塞内卡病毒(SVV)快速鉴别检测方法,本实验根据FMDV-O VP2基因序列和SVV P3基因序列,采用Primer Express3.0软件分别设计引物与探针,并经各反应条件的优化初步建立了可同时鉴别检测FMDV-O和SVV的双重荧光定量RT-PCR方法。利用该方法检测临床常见猪病毒,结果显示可同时检测出FMDV-O和SVV核酸,且与猪水泡性口炎病毒(VSV)、猪水疱病毒(SVDV)、猪瘟病毒(CSFV)、猪繁殖与呼吸综合征病毒(PRRSV)、猪细小病毒(PPV)、A型口蹄疫病毒(FMDV-A)、A-1型口蹄疫病毒(FMDVA-1)核酸均无交叉反应,并可检测到FMDV-O PanAsia株、cathay株、Ind-2001株和Mya-98株等主要流行株,特异性强;该方法对含FMDV-O和SVV拼接质粒标准品的最低检测限为7.17×10^(2)拷贝/μL,敏感性高;利用该方法检测了同一时间和不同时间提取的3种不同浓度的质粒标准品,结果显示批内和批间重复性试验Ct值的变异系数均小于3%,重复性好。利用本实验所建立的方法对30份临床样品进行检测,结果与各病毒单一荧光定量RT-PCR检测结果一致。本研究建立的FMDV-O和SVV双重荧光定量RT-PCR方法能够快速准确的鉴别检测FMDV-O和SVV,为口岸检疫的快速通关提供了技术手段。

miR-451a和miR-21-5p双重实时荧光定量PCR检测体系的建立及应用

目的为了提高微量样本中miRNA的检测通量和检测效率,本文建立了一种能够同时准确定量两种miRNA的双重实时荧光定量PCR(real time fluorogenic quantitative PCR)检测体系,并通过实际样本检测验证其应用于体液鉴别的效果。方法设计适用于miRNA双重检验的相关引物及探针并优化实验体系组分,建立基于TaqMan技术的miRNA双重实时荧光定量PCR检测体系并验证其特异性、灵敏度和可重复性;使用此检测体系对58份不同体液样本中的miR-451a与miR-21-5p进行检测,并借助miR-451a与miR-21-5p的比值鉴定法评估该体系的体液鉴别能力;使用该检测体系样本数据确定的最佳截断值对模拟案件样本进行鉴别。结果优化的检测体系能够实现对血液与非血液、月经血与外周血的100%区分,同时可以实现对模拟案件样本的准确鉴别。结论该双重实时荧光定量PCR检测体系将时间和材料成本均缩短至原来的一半,为后续建立更多重的实时荧光定量PCR检测体系并应用于体液鉴别打下了基础。

日勾维多细菌源菌双重PCR快速检测方法建立

建立日勾维多细菌源菌快速检测方法,快速有效地检出样品中的日勾维多细菌源菌。利用日勾维多细菌源菌的看家基因gyrB和ropB,设计2对特异性的扩增引物,以培养液作为DNA扩增模板,建立双重PCR快速检测方法,并通过优化扩增反应的退火温度,提高双重PCR的特异性;利用引物gyrB-F/gyrB-R和ropB-F/ropB-R(insert)扩增4株日勾维多细菌源菌,可得到2条特异性的目标DNA条带,但非目标菌会出现非特异性DNA条带。优化后的退火温度为65℃,以4株日勾维多细菌源菌为DNA模板时,可扩增出特异性的目标DNA条带;以大肠埃希氏菌、金黄色葡萄球菌、铜绿假单胞菌、阴沟肠杆菌和洋葱伯克霍尔德菌为DNA模板时,均检测不到DNA条带。当样品中的日勾维多细菌源菌达到4.4 CFU/mL时,双重PCR即可高灵敏检出样品中的日勾维多细菌源菌。可用双重PCR方法快速检出沐浴露、洗发水等淋洗类化妆品中的日勾维多细菌源菌。

羊泰勒虫与嗜吞噬细胞无浆体双重PCR检测方法的建立

为建立一种能快速对羊泰勒虫(ovine and caprine theileria)和嗜吞噬细胞无浆体(A.phagocytoph-ilum)同时进行检测的双重PCR方法。根据GenBank已报道的羊泰勒虫MPSP基因和羊嗜吞噬细胞无浆体16S rRNA基因设计合成了2对特异性引物,通过条件优化,建立了双重PCR检测方法。双重PCR可特异扩增出羊泰勒虫和嗜吞噬细胞无浆体目的条带,片段大小分别为875bp和394bp。该方法具有较好的特异性,对羊泰勒虫和嗜吞噬细胞无浆体的最低检出浓度为16fg/μL和1fg/μL。对采集的60份血液样本进行双重PCR检测,羊泰勒虫阳性率为46.67%(28/60),嗜吞噬细胞无浆体阳性率为13.33%(8/60),混合感染率为10%(6/60)。结果表明,双重PCR方法可用于羊泰勒虫和嗜吞噬细胞无浆体的快速诊断和流行病学调查。