汉坦病毒抗原性差异及其基因分型

用抗汉坦病毒单克隆抗体（Ｍｃ－Ａｂ）对汉坦病毒Ｂ７８株（来自病人血）和Ｒ１７８株（分离自褐家鼠）进行间接免疫荧光试验,以分析病毒的单克隆抗体反应谱,又用病毒免疫血清进行交叉中和试验,结果表明,两株病毒均具有双型（Ⅰ型／ＨＴＮ型和Ⅱ型／ＳＥＯ型）反应特征,但Ｒ１７８株基本上属于Ⅰ型。用汉坦病毒Ⅰ￣Ⅳ型型特异性引物进行ＰＣＲ扩增,Ｂ７８株用Ⅰ型和Ⅱ型引物均得到特异性扩增,而Ｒ１７８株虽经重复扩增均未见     

应用聚合酶链反应对我国不同来源肾综合征出血热病霉的型别分析

应用聚合酶链反应（ＰＣＲ）,对分离自不同地区、不同宿主来源的２６株肾综合征出血热病毒进行了分型,其中包括４个型别的国际标准株,用异硫氰酸胍－酚－氯仿方法从感染的Ｖｅｒｏ－Ｅ６细胞中提取总ＲＮＡ,设计了５对寡核苷酸引物,一对为汉坦病毒特异性引物;４对为不同型特异性引物。ＰＣＲ分型表明,２６株中除１株Ｒｒ可同时被汉坦（ＨＹＮ）和Ｓｅｏｕｌ（ＳＥＯ）两型特异性引物扩增外,其余２５株分别只被４个型别引物中的一个所扩增,依次为ＨＴＮ１６株,ＳＥＯ７株,Ｐｕｕｍａｌａ（ＰＵＵ）１株,ＰｒｏｓｐｅｃｔＨｉｌｌ（ＰＨ）１株。ＰＣＲ分型的结果与空斑减少中和试验完全一致,表明ＰＣＲ可以对肾综合征出血热病毒准成分型。应用限制性内切酶分析了扩增产物,结果与理论基本一致,证实了扩增产物的特异性。     

用温度循环法测定扩增DNA的序列比较汉坦病毒同型间的核酸序列

用温度循环法测定扩增ＤＮＡ的序列比较汉坦病毒同型间的核酸序列作者应用温度循环测序法对汉坦病毒血清型特异性引物扩增所得的ＰＣＲ产物进行序列测定以确定同一血清型几株病毒间序列的相似水平。测序用模板为上游引物和下游引物之间,测得的２８２,２６４和２９１个碱...     

PCR和生物素探针对HFRSV的检测和分型的探讨

分析比较肾综合征出血热病毒（ＨＦＲＳＶ）７６／１１８株和Ｒ＿（２２）株的核苷酸序列,根据引物设计原则及检测分型的目的,设计并合成了３对引物。１对引物取于两毒株间的高同源区段,作为共同引物和外引物;另两对引物取于两毒株间的低同源区段,分别作为野鼠型引物、家鼠型引物和内引物。建立了ＤＮＡ聚合酶链反应（ＰＣＲ）和ＮｅｓｔＰＣＲ方法,并用ＮｃｓｔＰＣＲ合成了两种型特异的生物素探针。ＰＣＲ检测７６／１１８、Ａ＿９、陈、Ｒ＿２、Ｒ＿２２５个毒株,用外引物时均扩增出１条约３００ｂｐ的条带;用内引物的野鼠型引物时,除Ｒ＿（２２）株之外,其余４株均扩增出１条约７０ｂｐ的条带。斑点杂交试验证实了ＰＣＲ检测分型的准确性。ＮｅｓｔＰＣＲ和生物素探针斑点杂交试验可以测出１－１０ｂｇ的目的ｃＤＮＡ。     

马铃薯卷叶病毒基因间隔区的克隆及序列分析

根据已报道的马铃薯卷叶病毒基因组序列．设计合成一对特异性引物,以马铃薯卷叶病毒中国分离株（ＰＬＲＶ－Ｃｈ）的ＲＮＡ为模板,反转录合成ｃＤＮＡ第一条链,经ＰＣＲ扩增后克隆于ｐＵＣ１９质粒中,进一步用ＰＣＲ鉴定、限制酶切分析和序列分析,结果表明：ＰＬＲＶ－Ｃｈ基因间隔区由１９７个核苷酸组成,与国外报道的荷兰ＰＬＲＶ－Ｎ加拿大ＰＬＲＶ－Ｃ,澳大利亚ＰＬＲＶ－Ａ,苏格兰ＰＬＲＶ－Ｓ各株系核苷酸序列具有很高的同源性,同源率依次为９９％、９８％、９３％、９８％。     

湖北省不同地区汉坦病毒M片段的分析研究

参考汉坦病毒（ＨＶ）的基因文库软件设计Ｍ片段Ｇ－１区型特异性引物,以ＨＶ　７６／１１８、Ｈ－１１４、Ａ－９及Ｒ－｛２２｝株ＲＮＡ为阳性模板,建立ＨＶ的分型方法──逆转录一半巢式聚合酶链反应（ＲＴ－ｈｅｍｉｎｅｓｔｅｄ　ＰＣＲ）,对湖北省不同地区分离的３０株ＨＶ进行分　型。结果显示：（１）建立的ＲＴ－ｈｅｍｉｎｅｓｔｅｄ　ＰＣＲ分型方法对ＨＶ两型的代表株７６／１１８（ＨＴＮ）、Ａ－９（ＨＴＮ）、Ｈ－１１４（ＨＴＮ）及Ｒ－｛２２｝（ＳＥＯ）ＲＮＡ进行了特异性扩增,其大小与理论值一致;此　法只能检测ＨＶ　ＲＮＡ,不能检测其它病毒ＲＮＡ。（２）分离于湖北省不同地区的３０株ＨＶ的分型结果　为汉滩型２１株、汉城型９株,其中长江以南汉滩型１２株、汉城型２株;长江以北汉滩型９株、　汉城型７株。这表明建立的ＲＴ－ｈｅｍｉｎｅｓｔｅｄ　ＰＣＲ用于ＨＶ的检测特异性好;分析湖北省不同　地区分离的３０株ＨＶ,显示湖北省ＨＦＲＳ流行为混合疫区;且在湖北地区具有一定的地理聚集性。     

马铃薯卷叶病毒中国株（PLRV—Ch）复制酶基因结构研究

用设计合成的两对特异性引物,以马铃薯卷叶病毒中国分离株ＰＬＲＶ－Ｃｈ ＲＮＡ为模板,经反转录ＰＣＲ扩增,将复制酶基因３＇端０．６ｋｂ和５＇端１．２ｋｂ,克隆于ｐＵＣ１９中,分别构建了重组质粒ｐＬＲ３和ｐＬＲ５,并分五段进行了序列分析。将获得的核苷酸序列氨基酸序列与国外报导的四个ＰＬＲＶ分离株的相应区段的序列同源性进行了比较。结果表明具有高度同源性。文中对核苷酸序列中存在的问题移码序列和其下游的茎环     

汉坦病毒陈株S基因编码区的克隆,序列分析及表达

从汉坦病毒陈株感染的ＶｅｒｏＥ６细胞裂解液中提取病毒ＲＮＡ,经逆转录ＰＣＲ获得病毒Ｓ基因编码区约１．３ｋｂｃＤＮＡ片段,克隆该片段后进行核苷酸序列测定,并与汉坦病毒７６１１８株进行同源性比较,结果二者核苷酸序列同源性为８６％,推导的氨基酸序列同源性为９７％。将该基因片段插入原核表达载体ｐＧＥＸ４Ｔ１,在大肠杆菌中获得高效表达。表达产物为ＧＳＴＮＰ融合蛋白。ＳＤＳＰＡＧＥ检测表达蛋白分子约７２ｋＤ左右。Ｗｅｓｔｅｒｎｂｌｏｔｉｎｇ和ＥＬＩＳＡ试验结果表明,表达产物可与多株抗汉坦病毒核蛋白的ＭｃＡｂ发生反应,其抗原表位及ＭｃＡｂ反应谱与７６１１８株相比存在某些差异。     

应用反转录-套式PCR方法检测肾综合征出血热病人血清中的汉坦病毒特异性RNA

采用５′端生物素标记汉滩病毒特异性寡核苷酸探针,结合磁性分离技术和异硫氰酸胍－酚一步法（胍酚法）提取病毒ＲＮＡ,进行反转录－套式ＰＣＲ,检测肾综合征出血热（ＨＦＲＳ）病人血清样本,胍酚法能检测血清中至少几个ＰＦＵ病毒的ＲＮＡ,比磁珠法敏感１０倍,整个检测过程在５小时完成。应用该方法对１３７份汉滩型和汉城型ＨＦＲＳ病人血清进行检测分型,总阳性率达６０．５０％。其中,病程在７日以内（急性期）的病人血清仍能检测到２２．７３％阳性率。扩增产物经打点杂交检测证实为特异性扩增,并能准确分型。与空斑减少中和试验（ＰＲＮＴ）分型的符合率为１００％。对２０份正常人及２４份非ＨＦＲＳ患者血清进行ＰＣＲ扩增,结果均为阴性。将全部试剂做成试剂盒,为基层单位早期诊断肾综合征出血热病人提供了操作简便、特异、敏感、快速、直接的诊断方法。     

水稻条叶枯病毒基因组组分3的克隆与序列分析

利用ＲＴ－ＰＣＲ技术,合成并扩增了水稻条叶枯病毒（ＲＳｔＶ）中国云南分离 物基因组组分３的全长ｃＤＮＡ。将ＰＣＲ产物克隆在载体ｐＣＲⅡ上,进行全序列测定。将所得核苷酸序列及其所推导的氨基酸序列与日本分离物Ｔ进行同源性比较,结果表明,在核苷酸水平上,两分离物的５’端非编码区序列相同,ｖＯＲＦ、ｖｃＯＲＦ及基因间非编码区序列的同源性分别为９７．６％、９６．８％及８７．６％,而３’端非编码区同源性为９８     

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.