草鱼呼肠孤病毒新分离株(GCRV991)的病毒学特性分析

从湖南长沙分离到一株致病性强的草鱼呼肠孤病毒(GCRV991),该病毒能使草鱼CIK,肥头鲤FHM细胞产生明显的CPE,对水生动物BF2,EPC及哺乳动物BHK,VERO细胞株不敏感.中和实验显示,GCRV873抗体能有效地中和GCRV991病毒颗粒,形成抗原抗体免疫复合物.纯化的病毒核酸与蛋白经SDS-PAGE分离,分别呈现11条清晰的核酸带及5条主要与2条微量结构多肽图谱,其核酸蛋白分子量大小与GCRV873相近似.该毒株基因组总分子量为14.48×106kD,大小范围是0.55～2.61×106kD;5条主要与两条微量结构多肽分子量近似值分别为136kD、132kD、65kD、43kD、34kD及138kD、82kD.上述结果提示,新分离的GCRV991与GCRV873具有相似的抗原性.     

草鱼呼肠孤病毒新分离株（GCRV991）的病毒学特性分析

从湖南长沙分离到一株致病性强的草鱼呼肠孤病毒 (GCRV991) ,该病毒能使草鱼CIK ,肥头鲤FHM细胞产生明显的CPE ,对水生动物BF2 ,EPC及哺乳动物BHK ,VERO细胞株不敏感。中和实验显示 ,GCRV873 抗体能有效地中和GCRV991病毒颗粒 ,形成抗原抗体免疫复合物。纯化的病毒核酸与蛋白经SDS PAGE分离 ,分别呈现 11条清晰的核酸带及 5条主要与 2条微量结构多肽图谱 ,其核酸蛋白分子量大小与GCRV873 相近似。该毒株基因组总分子量为 14.48× 10 6kD ,大小范围是 0 .5 5～ 2 .6 1× 10 6kD ;5条主要与两条微量结构多肽分子量近似值分别为136kD、132kD、6 5kD、43kD、34kD及 138kD、82kD。上述结果提示 ,新分离的GCRV991与GCRV873 具有相似的抗原性     

猪流行性腹泻病毒地方株LJB/03分离及培养特性

从黑龙江省某猪场疑为病毒性腹泻的发病猪采集腹泻粪便样品,以RT-PCR法扩增出猪流行性腹泻病毒M基因后,采用细胞培养法进行病毒分离。对细胞培养分离物进行间接免疫荧光、免疫电镜观察、RT-PCR及ELISA法检验,其中间接免疫荧光试验可见培养细胞中存在明显的特异性绿色荧光;免疫电镜下可见大小符合预期、有囊膜、花瓣状的典型冠状病毒结构特征;RT-PCR检测证实存在PEDVM基因;间接ELISA检测中平均P/N比值为7.6;从而确认为分离到一株猪流行性腹泻病毒(Porcine epidemic diarrhea virus,PEDV),命名为PEDVLJB/03株。随后,对该分离毒株的培养特性及如何提高病毒滴度进行探索。通过摸索该分离毒株的蚀斑形成条件,建立了PEDV蚀斑形成方法,并采用该方法进行病毒的蚀斑纯化,纯化得到PEDV大蚀斑克隆株和小蚀斑克隆株。对大、小两种蚀斑克隆株的病毒滴度测定结果表明,大小蚀斑克隆株细胞感染滴度相差明显。     

家蚕溶茧酶基因的真核表达及其产物的生物活性检测

为了研究家蚕 Bombyx mori 溶茧酶基因 （cocoonae）真核表达及其产物的生物活性,将溶茧酶基因（GenBank 登录号 EF428980）克隆至杆状病毒转移载体 pFastBac^TM 1 中获得 pFast-cocoonase,将其转化 DH10Bac 感受态细胞后,PCR 方法检测证实所分离的重组病毒 DNA 中含有目的片段溶茧酶基因。用脂质体法 转染家蚕 BmN 细胞,获得重组病毒。SDS-PAGE 分析显示,感染重组杆状病毒 Bac-cocoonase 的细胞表达产物在约为 27.6 kD 处出现特异性条带,这与预测的蛋白大小相符。用该表达产物与茧丝反应后,电镜下观察茧丝的形态,结果表明表达产物对茧丝的丝胶层有一定的水解作用。     

甲型肝炎病毒Vero细胞适应株的选育研究

将甲肝患者粪便中分离的甲型肝炎病毒在Vero细胞中进行适应性培养 ,选育高滴度适应株应用于甲肝灭活疫苗研究。在Vero细胞上连续传代 ,测抗原滴度和感染性滴度 ,满意后按WHO推荐的甲型肝炎灭活疫苗规程进行灭活疫苗试制研究。经Vero细胞 14次适应性传代后 ,病毒抗原滴度可高达 1∶2 5 6 0 ,感染性滴度为 8.2 3LogC CID50 /ml。试制的灭活疫苗HPSEC检测在 2 80nm时仅有一个高峰 ,SDS PAGE电泳 ,在 2 2kD、2 6kD和 33kD处有三条蛋白带 ,和HAVVP3、VP2和VP1的位置相同。ICR小鼠效力试验表明疫苗剂量 16 0 0EU/ml与Merck疫苗5 0U效果相似。通过研究获得了Vero细胞甲肝病毒适应株YN5株 ,初步证明可作为甲型肝炎灭活疫苗的候选毒株。     

鱼类培养细胞抗病毒基因差减cDNA文库的构建

紫外线灭活的草鱼出血病病毒（GCHV）能诱导鲫囊胚培养细胞（CAB）产生高滴度的干扰素,从而诱导宿主细胞基因表达的改变并处于抗病毒状态。提取灭活病毒诱导未经病毒诱导的CAB细胞mRNA,利用抑制性差减杂交技术,成功构建了鱼类培养细胞抗病毒基因差减cDNA文库。以鲫管家基因α－tubulin和β－actin作为差减指标,检测差减cDNA文库的差减效率分别高达2^15和2^7倍,表明经过病毒诱导后的细胞中,某些差异表达基因的富集效率也接近2^15倍。鱼类抗病毒基因差减cDNA文库的建立对快速分离、克隆鱼类抗病毒相关基因和认识鱼类细胞抗病毒免疫的分子机理有重要意义。     

中国本溪虹鳟一株弹状病毒的分离及初步研究

１９９０年４月,辽宁省本溪市虹鳟鱼种场的虹鳟稚鱼爆发大规模疾病,死亡率近１００％。取病鱼组织处理后接种于鱼类细胞,出现明显的细胞病变,测定细胞培养物中的病毒滴度,最高达１０￣（６．３）ＴＣＩＤ＿（５０／０．１ｍｌ）。感染病毒的细胞用１％营养琼脂糖覆盖后可形成０．５－１．５ｍｍ的蚀斑。分离到的病毒对氯仿敏感,不耐热、不耐酸,在细胞内复制的最适温度为１５℃。室内人工感染的虹鳟稚鱼能复制出与天然发病相同的症状。对感染病毒的细胞制成超薄切片,透射电镜观察,病毒长为１３１－１７３ｎｍ,平均１４８ｎｍ,直径为５８－９１ｎｍ,平均７１ｎｍ,形状为子弹状,表明是弹状病毒,有囊膜及纤突。采用挑斑法得到了纯化的病毒株,暂称之为传染性造血器官坏死症病毒中国本溪株ＩＨＮＶ－Ｂ。     

用蚀斑法进行麻疹疫苗的病毒滴定

按世界银行中国疫苗项目对麻疹疫苗检定的要求,建立了麻疹疫苗病毒滴定的蚀斑方法。以蚀斑法对Ｈｕ１９１株生产的冻干麻疹活疫苗样品进行了测定。结果发现,Ｈｕ１９１株生产的麻疹疫苗在琼脂和甲基纤维素覆盖下所形成的蚀斑大小及形状不同,但滴度无显著性差异;在室温和３７℃吸附的滴度无显著性差异,但细胞在３７℃生长较好;在本实验条件下,蚀斑滴定和ＣＣＩＤ５０测定的滴度呈正相关,蚀斑滴定相对较敏感;采用国产６孔聚苯乙稀培养板,Ｖｅｒｏ细胞单层,在３７℃吸附,用甲基纤维素覆盖,经结晶紫及甲醛固定染色后计数空斑,操作简便易行,结果特异敏感,重复性好,可用于麻疹疫苗病毒滴定     

锦鲤鳍条组织细胞系的建立及其生物学特性

采用组织块移植培养技术,对来源于锦鲤（Cryprinus carpiod）鳍条组织的细胞进行原代培养,建立了锦鲤鳍条组织细胞系,已稳定传代60多次,命名为Koi-Fin。锦鲤鳍条组织细胞为成纤维样细胞,最佳培养基为MEME,最适血清体积分数为10%,最适培养温度为25 oC,群体倍增时间为43.5 h。该细胞经液氮冷冻保藏12个月后采用台盼蓝染色,约（80.21±5.84）%的细胞具有细胞活性,复苏细胞生长旺盛。细胞染色体分析显示,第16代锦鲤鳍条组织细胞的染色体数目为正常二倍体2n=100,第40代细胞的染色体众数为52。病毒敏感性试验结果表明,Koi-Fin细胞系对锦鲤疱疹病毒（Koi Herpesvirus,KHV）敏感,可产生典型细胞病变效应,病毒滴度为107.86±0.51TCID50/mL。针对锦鲤疱疹病毒胸苷激酶（thymidine kinase,TK）基因设计特异性引物进行PCR检测,可扩增出病毒靶基因片段。     

AKT2基因短发夹结构RNA慢病毒载体的构建及鉴定

目的：构建丝/苏氨酸蛋白激酶2（AKT2）基因RNA干扰（RNAi）慢病毒载体。方法：利用公用网站按照RNAi序列设计原则,设计RNAi靶点序列并合成靶序列的Oligo DNA,退火形成双链DNA,与经MluI和ClaI进行酶切后的PLVTHM载体连接产生shRNA慢病毒载体。应用shRNA慢病毒载体转染293T细胞及U87细胞,测定病毒滴度,流式细胞仪测定U87细胞的转染效率,PCR及Western blot鉴定AKT2基因在U87细胞中的下调作用。结果：成功构建了shRNA-AKT2慢病毒载体,经测序与设计合成的靶向链完全一致。荧光显微镜下观察293T细胞感染效率大于90%,病毒滴度为3.59×107TU/ml;流式细胞仪测定对AKT2细胞的转染效率为86.93%。PCR测定shRNA载体感染U87细胞后AKT2的干扰效率为68%。Western Blot结果显示该慢病毒载体对AKT2的表达有较为显著的敲减作用。结论：成功构建了人胶质瘤细胞株AKT2基因RNAi慢病毒载体,为后续的体内外功能学试验创造了条件。     

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.     

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.     

肝癌中HBV和HCV基因和抗原的分布及意义

采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细     

Selection with two alleles and complete dominance

For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.