禽网状内皮组织增生流行病学概述

禽网状内皮组织增生病病毒属于C型反转录病毒。该病毒可引起家禽免疫功能抑制和慢性肿瘤。本文就禽网状内皮组织增生病病毒的生物学特性、引起免疫抑制机制、引起肿瘤的发生和预防措施的研究进行简要综述。     

禽网状内皮组织增生流行病学概述

禽网状内皮组织增生病病毒属于C型反转录病毒。该病毒可引起家禽免疫功能抑制和慢性肿瘤。本文就禽网状内皮组织增生病病毒的生物学特性、引起免疫抑制机制、引起肿瘤的发生和预防措施的研究进行简要综述。     

JC病毒研究进展及其在人类起源研究中的应用

综述了JC病毒的遗传特性、传播途径及相关疾病。JC病毒是人类多瘤病毒的一种,在人群中广泛存在。JC病毒感染发生在人的童年时期,没有明显的症状,对绝大多数人没有危害,但对于免疫力缺陷和长期服用免疫抑制药物的患者,能够引起致命的进行性多灶性白质脑病(Procreative Multifocal Leukoence Phalopathy,PML)。由于JC病毒属无症状感染,其具体感染途径至今不清楚。JC病毒具有家庭内部传播的特点,从父母传给子女,属事实上的垂直传播。因此,可以通过研究JC病毒的基因分型来研究人类的起源和迁移。     

小鼠诱导转基因传代细胞对AFP粪便标本中脊灰和其他肠道病毒的分离鉴别研究

报告４６份ＡＦＰ粪便标本用Ｌα、ＲＤ和Ｈｅｐ－２三种细胞作病毒分离，阳性率分别为２６．０９％、６０．８７％、４３．４８％。同步分离出脊灰病毒Ⅰ型３株，Ⅱ型２株，Ⅲ型４株，Ⅰ＋Ⅱ型１株，Ⅰ＋Ⅲ型１株，混合Ｐ２＋Ｅ１株。脊灰病毒总分离阳性率为２８．９５％。非脊灰肠道病毒分离阳性率分别为０％、３６．９６％、２３．９１％。从６份第１次分离结果阴性的高危病例和高度临床病例粪便标本重新分离出１株Ⅲ型脊灰病毒和３株非脊灰肠道病毒。应用Ｌα细胞不仅能作型别鉴定，而且能区别脊灰病毒和非脊灰肠道病毒混合感染     

汉滩病毒VLP的构建及其生物学特性的研究

汉滩病毒是一种单负链RNA病毒,在我国主要引起以发热、出血、急性肾功能损害和免疫功能紊乱为主要特征的肾综合征出血热(HFRS),临床治疗尚无特效治疗药物,主要依靠灭活疫苗进行预防,但其诱导机体产生病毒中和抗体滴度较低,诱导细胞免疫反应能力差。病毒样颗粒(virus like particles,VLP)具有病毒天然蛋白成分和构象,但不含病毒核酸,是理想的候选疫苗。将表达汉滩病毒包膜糖蛋白Gn和Gc的M片段与含有表达汉滩病毒核蛋白的S片段的载体在哺乳动物细胞中共表达,包装出汉滩病毒VLP,对包装出的VLP进行初步纯化和生物学特性的鉴定。     

SARS相关冠状病毒及与动物冠状病毒的关系

比较了6株人、5株禽、4株鼠、7株牛、2株猫、9株猪、4株犬和5株人非典型肺炎共42株冠状病毒S糖蛋白基因序列。DNAstar软件比较表明，人冠状病毒S基因核苷酸序列同源性介于27．2％～99．5％；禽的介于81．5％～100％；鼠的介于79．5％～89．6％；牛的介于97．7％～100％；猫的介于56．2％～93．9％；猪的介于54．8％～100％；犬的介于64．9％～98．8％；人非典型肺炎病毒的介于99．9％～100％。非典型肺炎冠状病毒与所有比较的42株序列的同源性均低于30．8％，预示该病毒似乎不是其它病毒株变异进化的结果，而是人类和畜禽从未接触过的一种新型病毒。     

斜纹夜蛾核型多角体病毒日本株(C3)p10基因的克隆及序列分析

从斜纹夜蛾核多角体病毒(Spodoptera litura mukieapsid nucleopolyhedrovirus，Splt MNPV)日本株(C3)基因组中克隆了p10基因．核苷酸序列分析表明，该克隆片断涵盖了318bp的读码框及5’端启动子区191bp和3’端终止区62bp的序列．在起始密码子ATG上游-63～-59bp处有一杆状病毒晚期和晚晚期启动子基序TAAG．联配分析表明，Splt MNPV日本株(C3)的核苷酸序列和氨基酸序列与其它9种核多角体病毒的同源性有较大差异．以p10基因为基础绘制的杆状病毒分子进化树将家蚕核多角体病毒(Bombyx mori nuchopolyhedrovirus，BmNPV)与苜蓿丫纹夜蛾核多角体病毒(Autographa californica multicapcid nucleopolyhedrovirus，AcMNPV)归到同一分枝，这与以gp37基因和egt基因为基础绘制的杆状病毒分子进化树结果一致．     

甜菜夜蛾核多角体病毒基因组13.7～21.6 m.u.区域的分析

甜菜夜蛾核多角体病毒(Spodoptera exigua multicapsid nucleopolyhedrovirus,SeMNPV)基因组13．7～21．6m．u．区域是SeMNPV的重组热点区。以SeMNPV美国分离株SeUS1为模板,长片段PCR对SeUS1的13．7～21．6m．u．区域扩增,得到11．3kb,2．0kb和0．7kb3个片段。对照已发表的SeMNPV基因组序列,11．3kb片段是具完整SeMNPV序列基因型的产物,2.0kb和0．7kb片段表明SeUS1中还存在两种缺失突变株。对2．0kb和0．7kb片段的序列分析揭示了这两株突变株在缺失部位的DNA一级结构。对三株重组SeMNPV病毒(SeXDl、SeXD2和SeXD3)的分析发现,它们和野生型病毒SeUS1中的一个基因型一样,均缺失了SeMNPV nt 18513～29105之间长10593bp的片段,暗示SeUS1中一株自发形成的缺失突变体在离体细胞中具有复制优势。将该片段基因排列与其它10种基因组序列已测定的杆状病毒比较,发现两个在GroupⅡ NPVs中保守的基因簇。最大简约性法对部分基因的系统发育分析表明,缺失片段中某些基因可能存在于杆状病毒分化之前的病毒基因组中。     

脊髓灰质炎病毒I型单克隆抗体的制备

目的: 为建立脊灰病毒Sabin株I型特异的单克隆抗体．方法:以Vero细胞增殖病毒并用蔗糖密度梯度离心法纯化后,用病毒免疫SPF级Balb/c小鼠．取小鼠免疫脾淋巴细胞与SP2/0-Ag14骨髓瘤细胞进行细胞融合,通过间接 ELISA 法筛选抗体阳性的杂交瘤细胞,并用有限稀释法克隆化．用细胞培养法制备脊灰病毒单抗,并以中和试验测定单抗效价．结果:获得了8株分泌抗脊灰病毒Sabin株I型单克隆抗体的杂交瘤细胞株,其中1株G8G7能够稳定分泌抗体．间接ELISA 法测得单抗的效价为1∶8,中和试验测得中和抗体的效价为1∶58．结论:G8G7分泌的抗体为抗脊灰病毒Sabin株I型特异的单克隆抗体.     

新疆普氏野马鼻肺炎病毒的分离鉴定

从新疆昌吉州吉木萨尔野马饲养繁殖中心送检的野马病料中分离到一株病毒,并对其进行了全面鉴定．该病毒株在ＢＨＫ－２１细胞上连传６代出现典型细胞病变,用适应ＢＨＫ－２１细胞的病毒接种鸡胚成纤维细胞、乳豚鼠肾原代细胞、豚鼠睾丸细胞均出现程度不同的细胞病变．在电镜下可见到典型的马鼻肺炎病毒粒子（疱疹病毒样颗粒）．病毒对５－碘脱氧尿核苷、氯仿、乙醚等敏感．在ｐＨ３下失活,５６℃３０ｍｉｎ灭活．病毒能被马鼻肺炎病毒标准阳性血清所中和．病毒接种乳豚鼠出现典型致死性肝炎．结果表明所分离病毒为马鼻肺炎病毒,并将该毒株定名为ＰＨ９３－１株     

Chemical basis of antigenic variation in foot-and-mouth disease virus

One of the difficulties in controlling foot and mouth disease by vaccination is the occurrence of the virus as seven distinct serotypes because immunity conferred by vaccination against one serotype leaves the animals susceptible to infection by the other six. Moreover, the antigenic variation, even within a serotype, can be so great that immunity against the homologous strain of virus need not necessarily ensure protection against infection by other viruses within that serotype. Here we report the separation of three natural antigenic variants, distinguishable in cross-neutralization tests from an isolate of foot-and-mouth disease virus (FMDV). The serological differences could also be demonstrated by antisera elicited by synthetic peptides corresponding to residues 141-160 of the capsid polypeptide VP1, showing that this region contains a major immunogenic site of the virus. The results have practical implications for the choice of viruses for vaccine production.     

计算机病毒免疫技术的新途径

首先给出了计算机病毒免疫的严格定义,并在此定义下分析了它在同计算机病毒进行信息对抗中的作用与地位。同时,还给出了通过加强自主访问控制和设置磁盘禁写保护区来实现病毒免疫的基本构想。     

T-cell responses to human AIDS virus in macaques immunized with recombinant vaccinia viruses

There is much interest in developing vaccines against acquired immune deficiency syndrome (AIDS), which is caused by a retrovirus termed human immunodeficiency virus (HIV). Isolates of this virus include human T-lymphotropic virus type III (HTLV-III), lymphadenopathy-associated virus (LAV), and AIDS-associated retrovirus (ARV). Several approaches towards the development of an AIDS vaccine result in the production of antibodies in subprimates. These methods involve the use of: antigens isolated from the AIDS virus; viral antigens expressed by transfected cells or by recombinant vaccinia viruses; and particular synthetic peptides of viral antigens. Because T-cell-mediated immunity (in addition to antibodies) is involved in resistance to diseases and death caused by various enveloped viruses, we sought to determine whether potential AIDS vaccines can induce T-cell responses against the AIDS virus. Here we report that immunization of non-human primates, Macaca fascicularis (macaques), with recombinant vaccinia viruses that express LAV envelope glycoproteins gp41 and gp110 results not only in the production of antibodies against the LAV envelope antigens but also in the generation of T-cells that proliferate and produce the lymphokine interleukin-2 (IL-2), in response to stimulation with purified LAV. We believe this is the first report demonstrating T-cell-mediated immunity to the virus that causes AIDS.     

Combined immunity of DNA vector and recombinant vaccinia virus expressing Gag proteins of equine infectious anemia virus

In order to develop a new vaccine candidate for equine infectious anemia virus (EIAV), gag gene of Chinese donkey leukocyte attenuated strain (EIAV DLV) and its parental virulent strain (EIAV LN) were inserted respectively into the TK region of the Tiantan strain (VV) of vaccinia virus by homologous recombination and the positive clone was confirmed by blue plaque assay. Protein expression was examined by Western blot. Prime and prime-boost procedures were used to immunize mice with two DNA vectors and two recombinant vaccinia viruses expressing EIAV Gag proteins. The results showed that the specific lysis of CTL responses in the DNA rVV groups was stronger than those in the DNA groups, amounting to 31%. Although the levels of specific antibodies were not significantly different, we could conclude that the recombinant vaccinia virus could boost the cellular responses following DNA vector priming. There was no detectable difference between the immune responses induced by DLV and LN Gag proteins. This data demonstrates that the combined immunity of DNA vector and recombinant vaccinia virus expressing EIAV gag proteins, utilizing the prime-boost procedure, can drive immunized mice to produce powerful cellular responses. These results lay an important foundation for the development of a new EIAV genetic engineering vaccine.     

利用节理张量确定岩体代表性单元体积

代表性单元体积 ( REV)是工程地质重要概念之一 ,目前 REV的确定尚无确切的量化方法。利用节理张量确定 REV的方法是利用现场节理量测资料 ,通过节理统计和岩体结构面网络模拟技术 ,计算岩体的 REV。该法可用于确定野外现场原位测试或室内实验试件的尺寸     

Neutralizing antibodies derived from the B cells of 1918 influenza pandemic survivors

Investigation of the human antibody response to influenza virus infection has been largely limited to serology, with relatively little analysis at the molecular level. The 1918 H1N1 influenza virus pandemic was the most severe of the modern era. Recent work has recovered the gene sequences of this unusual strain, so that the 1918 pandemic virus could be reconstituted to display its unique virulence phenotypes. However, little is known about adaptive immunity to this virus. We took advantage of the 1918 virus sequencing and the resultant production of recombinant 1918 haemagglutinin (HA) protein antigen to characterize at the clonal level neutralizing antibodies induced by natural exposure of survivors to the 1918 pandemic virus. Here we show that of the 32 individuals tested that were born in or before 1915, each showed seroreactivity with the 1918 virus, nearly 90 years after the pandemic. Seven of the eight donor samples tested had circulating B cells that secreted antibodies that bound the 1918 HA. We isolated B cells from subjects and generated five monoclonal antibodies that showed potent neutralizing activity against 1918 virus from three separate donors. These antibodies also cross-reacted with the genetically similar HA of a 1930 swine H1N1 influenza strain, but did not cross-react with HAs of more contemporary human influenza viruses. The antibody genes had an unusually high degree of somatic mutation. The antibodies bound to the 1918 HA protein with high affinity, had exceptional virus-neutralizing potency and protected mice from lethal infection. Isolation of viruses that escaped inhibition suggested that the antibodies recognize classical antigenic sites on the HA surface. Thus, these studies demonstrate that survivors of the 1918 influenza pandemic possess highly functional, virus-neutralizing antibodies to this uniquely virulent virus, and that humans can sustain circulating B memory cells to viruses for many decades after exposure-well into the tenth decade of life.     

Enhanced virulence of influenza A viruses with the haemagglutinin of the 1918 pandemic virus

The 'Spanish' influenza pandemic of 1918-19 was the most devastating outbreak of infectious disease in recorded history. At least 20 million people died from their illness, which was characterized by an unusually severe and rapid clinical course. The complete sequencing of several genes of the 1918 influenza virus has made it possible to study the functions of the proteins encoded by these genes in viruses generated by reverse genetics, a technique that permits the generation of infectious viruses entirely from cloned complementary DNA. Thus, to identify properties of the 1918 pandemic influenza A strain that might be related to its extraordinary virulence, viruses were produced containing the viral haemagglutinin (HA) and neuraminidase (NA) genes of the 1918 strain. The HA of this strain supports the pathogenicity of a mouse-adapted virus in this animal. Here we demonstrate that the HA of the 1918 virus confers enhanced pathogenicity in mice to recent human viruses that are otherwise non-pathogenic in this host. Moreover, these highly virulent recombinant viruses expressing the 1918 viral HA could infect the entire lung and induce high levels of macrophage-derived chemokines and cytokines, which resulted in infiltration of inflammatory cells and severe haemorrhage, hallmarks of the illness produced during the original pandemic.     

基于免疫和代码重定位的计算机病毒特征码提取与检测方法

针对当前感染率高、威胁性极大的感染型计算机病毒,提出了一种基于免疫和代码重定位的计算机病毒特征码提取与检测方法.借鉴生物免疫系统机理,定义了计算机系统中的自体、非自体、抗体、病毒检测器、病毒基因等免疫概念,利用感染型病毒独特的代码重定位特性来提取病毒基因、构建病毒基因库,并在此基础上建立了自体/非自体、病毒基因库和病毒检测器动态演化模型.理论分析与实验结果表明,本方法有效克服了传统方法存在的自体集完备性问题和病毒检测器抗体完整性问题,因而比传统方法有更好的效率与适应性.      

基于REV的岩质边坡力学参数模拟试验方法

从岩体宏观连续性假设出发,引入岩体表征单元体(REV)概念.首先根据岩块的三轴与卸载回弹试验以及结构面的室内直剪试验确定其基本力学参数;然后以数值模拟试验方法,依据当岩体区域体积达到并超过岩体REV尺寸时其力学性质趋于稳定的变化规律,对岩质边坡岩体REV的存在以及大小进行确定;最后根据满足REV尺寸的三维模型最终计算出对应边坡岩体的力学参数.