HIV-1抗体蛋白印迹确认与核酸检测复核对比研究

应用病毒核酸载量法NASBA和HIV-1 RNA的巢式逆转录PCR(nested RT-PCR)法与HIV抗体蛋白印迹(WB)方法,对经过初筛的44例HIV-1抗体阳性标本进行了对照检测研究。发现了2例(gp160、p24)和1例(gp160g、p120p、66、p24)的特殊阳性样本,经NASBA法和该RT-PCR法核酸检测为阴性;WB确认的4例gp160阳性带、1例p24、p17阳性带和13例p24阳性带,经NASBA法和该RT-PCR法核酸检测也为阴性;而WB确认的其余全部带型的抗体阳性标本经过NASBA法和该RT-PCR法检测均为阳性。该研究表明对只有gp160p、24和gp160、gp120p、66、p24的特殊阳性标本和以p24为主的抗体不确定标本需要用RT-PCR或NASBA方法进行核酸检测,以进一步确认。     

巢式荧光定量RT-PCR检测中枢神经系统HCV方法的构建

目的 建立丙型肝炎病毒5′NCR基因的巢式荧光定量RT-PCR检测方法 ,用于中枢神经系统感染超低浓度HCV的准确和快速定量检测.方法 选择高度保守区5′NCR基因片段,设计并合成相应的特异性引物和探针,建立巢式荧光定量RT-PCR检测中枢神经系统感染样本中的超低浓度HCV正负链RNA的方法 .并对32例血清HCV抗体检查阴性的病毒性脑炎患者脑脊液有核细胞和外周血单个核细胞(PBMC)进行检测.结果 可特异性地检出脑脊液有核细胞及PBMC中HCV正负链RNA,最低检出浓度均可达7.85 copies/μl,与其他单股正链RNA病毒如登革热病毒(DEV)无交叉反应.32例血清HCV抗体检查阴性样本脑脊液有核细胞和PBMC中 HCV 5′NCR正链片段阳性的分别为1例(1/32)和2例(2/32),负链片段阳性的分别为1例(1/32)和0例(0/32).结论 本方法 的构建适用于中枢神经系统感染超低浓度HCV正负链RNA检测,且快速有效、敏感性和特异性较高,不易出现假阳性,可有效提高检出率,进一步完善目前临床常规检测HCV的方法 .     

丙型肝炎病毒分片段抗体检测蛋白质芯片质控参比品的建立及质量验证

建立能同时检测丙型肝炎病毒(HCV)嵌合抗体、核心抗体和NS3、NS4、NS5抗体的蛋白质芯片质控参比品,对质控合格的芯片进行质量验证。用3种HCV EIA试剂分别检测从3家医院收集的丙型肝炎病毒感染患血清及其他非HCV感染患血清,从3种EIA试剂同时阴性或阳性的血样中挑取阳性和阴性血清,然后用RNA hyb PCR试剂进行检测,从中再选取部分样本用RIBA3．0进行检测,确定HCV分片段抗体检测蛋白质芯片质控参比品。经质检合格的芯片用中国药品生物制品检定所的HCV参比品进行检定。通过490例临床标本的检测对芯片的质量进行进一步的验证。从收集的240份丙型肝炎病毒感染患血清及其他非HCV感染患血清筛选出30份血样(15份阳性,15份阴性)作为HCV分片段抗体检测蛋白芯片质控参比品。中国药品生物制品检定所的80份HCV参比品检定结果表明,混合抗体阳性检出率为39／40,阴性符合率为40／40,总符合率为98．7％;核心抗体阳性检出率为27／40,阴性符合率为40／40;NS3抗体阳性检出率为26／40,阴性符合率为39／40;NS4抗体阳性检出率为19／40,阴性符合率为40／40;NS5抗体阳性检出率2／40,阴性符合率为40／40。490例临床标本的检测结果表明,对于194例HCV阳性标本,蛋白质芯片混合抗体与ELISA的符合率达99．5％,分片段抗体符合率达97．4％,两种方法检测结果不符的标本经RIBA试剂确认,蛋白质芯片与RIBA试剂的符合率高度一致。对于296例各种HCV抗体阴性标本,蛋白质芯片检测结果全部为阴性。以上结果表明,制备的丙型肝炎病毒分片段抗体检测蛋白质芯片质控参比品可用于芯片生产的质量控制,经质控合格的芯片符合国家标准的要求,可用于临床检测。     

95例肺炎支原体快速液体培养阳性标本分析

目的:采用巢式PCR法(nPCR)及全自动微生物鉴定仪对肺炎支原体(MP)快速液体培养阳性标本进行分析,探讨MP快速培养假阳性情况及原因.方法:收集95例MP快速液体培养阳性标本,巢式PCR检测MP核酸,用全自动微生物鉴定仪检测导致培养假阳性的微生物.结果:95例MP快速液体培养阳性标本中,90例巢式PCR结果阴性,假阳性率94.7%;经全自动细菌鉴定仪鉴定,97.8%为真菌所致.结论:普通的敏感细菌在MP快速液体鉴定培养基中可以被有效抑制;真菌是引起的快速培养假阳性的主要原因.     

啮齿类动物中汉坦病毒感染血清学和病原学检测方法比较研究

致病性汉坦病毒的宿主主要为啮齿类动物,其病毒感染状况是人间疫情发生的关键影响因素,可通过检测宿主动物标本中病毒基因组RNA、蛋白抗原及特异性抗体而进行监测。本研究利用367份鼠肺及鼠血标本,对双抗原夹心ELISA(ELISA)、实时荧光RT-PCR(RT-PCR)和免疫荧光(IFA)等三种分别检测抗体、核酸和抗原的方法进行比较评估。ELISA法检出抗体阳性鼠血标本46份,阳性率为12.53%;RT-PCR法检出病毒RNA阳性鼠肺标本28份,阳性率为7.63%;IFA检出抗原阳性鼠肺标本24份,阳性率为6.54%。宿主动物组织标本中检出汉坦病毒RNA和(或)结构蛋白抗原的标本,对应的血液标本中可检出病毒特异性抗体,100%(24/24)IFA检测阳性标本和89.3%(25/28)RT-PCR检测阳性标本对应血标本ELISA抗体检测阳性,反之亦然,检出抗体的标本基本包含了可检出抗原和RNA的标本。RT-PCR与IFA检测结果差异无显著性(χa2=0.64,P0.05),一致性检验Kappa系数为0.71,一致性高(Z=13.66,P0.05),首先对血标本开展基于ELISA的特异性抗体检测,可显著缩小RT-PCR或IFA法检测病毒RNA或抗原的范围(χb2=12.04,χc2=20.05,P0.05)。本研究为宿主动物汉坦病毒感染实验室监测方案优化提供了有益的依据。     

吉林省延边地区丙型肝炎病毒基因型分布

为了解延边地区不同丙型肝炎病毒(HCV)基因型的分布特点,应用逆转录-聚合酶链反应(RT-PCR)技术,检测了48例本地区抗HCV阳性血清,结果有29例出现HCVRNA阳性.再利用限制性片段长度多态性(RFLP)技术,对29例RT-PCR阳性标本进行HCV基因分型.结果延边地区主要流行HCVⅡ型,其次是HCVⅢ型,也存在HCVⅡ/Ⅲ混合型,且HCVⅢ型的感染率较高.     

实时定量RT-PCR对乙型肝炎病毒全长RNA(fRNA)的定量检测

目的:建立一种简便的定量检测慢性乙型肝炎患者血清中终止于聚腺苷酸化位点的乙型肝炎病毒全长RNA(f RNA)的方法。方法:选取53例未治疗的乙型肝炎患者及22例HBs Ag阴性的健康者为研究对象,使用锚定oligo-d T的引物对其血清中f RNA进行实时定量反转录PCR检测,统计分析其与HBV DNA、HBcr Ag和HBe Ag的相关性。结果:对f RNA进行实时荧光定量RT-PCR检测的下线为2.3 log copies/ml,标准曲线的相关系数为0.99(P0.0001)。53例乙型肝炎患者中,29例(54.7%)可以检测到f RNA,22例正常对照中没有检测到f RNA。27例HBe Ag阳性和/或高水平HBV DNA的患者全部检测到f RNA,26例HBe Ag阴性并且低水平HBV DNA的乙型肝炎患者中有2例(7.7%)检测到f RNA(P0.0001)。HBe Ag阳性患者血清中f RNA水平高于HBe Ag阴性患者(5.0±0.3 vs.2.9±0.4 log copies/ml,P0.001)。f RNA与HBV DNA/HBcr Ag具有显著相关性(r=0.905、0.881,P0.0001)。Hayashi's定量分析法I显示f RNA与HBV DNA相关性强于其与HBcr Ag的相关性。结论:与HBV DNA和HBe Ag一样,f RNA可作为常规检测判断HBV的复制水平并指导用药。     

NASBA荧光分子信标技术定量检测丙型肝炎病毒

建立NASBA荧光分子信标探针检测技术,并对国家HCV标准品、人工构建HCVRNA野生株及HCV抗体阳性不同人群进行检测。实验结果:该方法检测HCV的灵敏度为103拷贝ml血清,阴性参比品的符合率为100%;检测的线性范围为103拷贝～109拷贝ml血清;精密性(CV值)小于6%,在HCV抗体阳性人群中HCVRNA的检出率在45%～65%之间。结论:该方法在HCVRNA临床定量检测中具有良好的灵敏度、特异性、重复性与实用性。     

检测低拷贝数HBV DNA含量的临床研究

目的:了解不同试剂在应用实时荧光定量聚合酶链反应(FQ-PCR)以及巢式PCR方法在检测低拷贝数的HBV DNA量的差异与灵敏度。方法:用上海复星医学科技发展有限公司(A方法)检测出了68例HBV DNA结果为5.1×101-1.0×103拷贝数/亳升的低拷贝数标本。然后,三家不同公司的试剂(方法 B、方法 C、方法 D)对这些样本进行复核。另外,巢式聚合酶链反应PCR法检测此68例标本。随访巢式PCR结果为阳性的10例低拷贝数HBV DNA的病人。结果:用四种方法(A、B、C、D)检测的68个样本的HBV DNA拷贝数结果如下:无拷贝(0,9,12,4);101-102(21,17,18,22);102-103(47,36,28,35),大于103(0,6,10,7)。同时,用巢式聚合酶链反应检测此68例标本,有55例检测为阳性,有13为阴性结果。巢式PCR结果为阳性的10例低拷贝数HBV DNA含量的病人,随访发现此10病人有8例均在1~3月后出现HBV DNA的反跳,并伴肝功能的不正常,其HBV DNA的含量均在104拷贝数/毫升以上。结论:目前所用的实时荧光定量聚合酶链反应(FQ-PCR)的方法和试剂对低拷贝数HBV DNA存在不稳定性和不确定性。巢式PCR法对低拷贝数HBV DNA的检测灵敏度要远高于实时荧光定量PCR法。该研究提示测对抗病毒治疗过程中患者进行低拷贝数HBV DNA的检将提供有效的药物评价和预后信息。     

RT套式PCR检测血浆HCV RNA及与抗HCV检测的比较

应用微量血清热变性法提取核酸,逆转录套式聚合酶链反应(RT-nest PCR)检测血浆HCV RNA,并与抗HCV ELISA检测结果比较,对HCV RNA阳性标本进行HGV RNA的筛查.结果在32例抗HCV阳性和20例抗HCV阴性血浆中,HCV RNA分别检出18例和2例,总符合率为70%,20例HCV RNA阳性者中有2例合并感染HBV,1例合并感染HGV.证明血浆样本中抗HCV与HCV RNA间存在很大的相关性.     

Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis

It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.     

A Unique Protease Cleavage Site Predicted in the Spike Protein of the Novel Pneumonia Coronavirus (2019-nCoV) Potentially Related to Viral Transmissibility

正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

The structure, reproduction and taxonomy of Vidalia and Osmundaria (Rhodophyta, Rhodomelaceae)

Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.     

New or rare chromosome counts in Artemisia L. (Asteraceae, Anthemideae) and related genera from Kazakhstan

Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.