关键词： 脊髓灰质炎   病毒   核糖核酸  

摘要： 脊髓灰质炎病毒RNA 5′及3′端各有一段非编码(NC)区,长度分别为745及73核苷酸。现已发现5′NC区与病毒mRNA翻译时的内启动、病毒RNA的复制有关。同时也是决定病毒神经毒力的主要部分。3′NC区的完整性直接与病毒的感染性有关。

关键词： 卫生保健工作   上海市虹口区   卫生工作   上海市区   慢病防治   战略目标   预防保健   脊髓灰质炎疫苗   儿童死亡率   人民健康水平  

摘要： 虹口区位于上海市区的东北部,总面积23.47平方公里,有17个街道和一个镇,333个居委会。有蒙古族、回族,满族等19个少数民族。1989年全区人口850 493人,其中14岁以下的儿童占16.04％,60岁以上的老人占16.58％。世界卫生组织提出的“2000年人人享有卫生保健”的战略目标,我国政府早已承诺并把它作为卫生工作的组成部分。

关键词： 脊髓灰质炎   病毒   抗原  

摘要： 脊髓灰质炎(以下简称脊灰)病毒,具有三种比较稳定的血清型,近年来,先后有应用中和性单克隆抗体(N-McAb)分析型内毒株间抗原差异的报导.免疫荧光单克隆抗体(F-McAb),在识别脊灰病毒抗原表位与中和性单克隆抗体具有相似的特性,且检测的活性范围比后者宽.为了研究我省脊灰病毒型内各毒株间的抗原性差异,以便更好的指导脊灰预防,我们用F-McAb对四川省1980～1990年79株脊灰病毒,采用交义间接免疫荧光试验,进行了抗原性分析,现将结果报告如下.

关键词： 脊髓灰质炎   病毒   嵌合病毒   载体  

摘要： 脊髓灰质炎病毒(Polio)具有多个结构精细的中和抗原位点(N-Ag),能分别刺激机体产生中和抗体。利用这一性质,近年来陆续报道了以Folio作载体进行病毒嵌合。利用基因工程方法在N-Ag位点进行几个氨基酸的替换所产生的嵌合病毒具双重抗原性。这已在Polio型间(Ⅰ/Ⅱ、Ⅰ/Ⅲ)、Polio/HIV、Polio/乳头状病毒等方面取得进展。并且由于Polio病毒的稳定性及疫苗加工的成功经验,以Polio作载体构建的嵌合疫苗很可能开创疫苗生产的另一新途径。

关键词： 脊髓灰质炎   病毒   单克隆抗体  

摘要： 用PcAb血清NT与F-McAb IF对286株Polio Ⅰ、Ⅱ和Ⅲ型病毒进行定型,结果两者的符合率Ⅰ型为100％,Ⅱ型和Ⅲ型均为99％。Ⅰ型与Ⅱ、Ⅲ型符合率的微小差异,可能是实验技术上的误差所致,也可能是McAb本身识别抗原表位的局限性所致。提示要得到真正理想的型特异McAb,必须用大量有代表性的毒株进行交叉试验。本试验证明,F-McAb IF可以代替PcAb参考血清NT作为Polio病毒的定型方法。IF比NT简单、快速、特异和敏感,是组装试剂盒的理想材料。

关键词： STOOL ISOLATES   NEUROVIRULENCE   FORMULATION   INTERTYPIC RECOMBINATION  

摘要： Derivatives of Sabin 3 shed from recipients of oral poliovirus vaccine in the United States (U.S.) were examined for genetic changes identified in strains excreted by vaccinees in the United Kingdom [U.K.;Evans et al., 1985;Cammack et al., 1988, Macadam et al., 1989]. Among the eight primary vaccinees studied, the duration of excretion and molecular evolution of type 3 strains varied greatly. The period of virus excretion after vaccination ranged from as few as 2 days to as many as 36 days. Nucleotide sequence analysis of viral RNAs extracted from shed virus indicated that only fifty percent of the vaccinees exclusively excreted strains in which the attenuating mutation at nucleotide 472 in the 5' noncoding region of the genome had reverted from uracil (U) to cytosine (C), the nucleotide found in neurovirulent strains. Compared to the wild-type Leon strain, the low activity of stool isolate KW4 in a complete monkey neurovirulence test demonstrated that presence of C at 472 does not render a type 3 strain pathogenic. Conversely, an isolate was identified which efficiently replicated in monkey nervous tissue and maintained the attenuated U at 472. Oligonucleotide fingerprinting and sequence analysis of viral RNAs from stool isolates indicated that one vaccinee (KW) eventually excreted intertypic recombinant strains consistent with those reported in the U.K. studies. Unique to this study, one vaccinee (KS) excreted nonrecombinant virus possessing U at 472 for up to 21 days. The significance of the KS strain profile in relation to differences in the U.S. vaccine compared to the vaccine distributed in the U.K. and other countries is discussed.

关键词： Cell Growth   Extenders   Poliomyelitis   Vero Cells   Extender Device Component   Cells   Poliovirus   Serum   Production   viruses  

摘要： A serum extender, SERASUP II, was evaluated for its ability to maintain VERO cell cultures at long term, and for its influence on virus production by cells adapted to that medium. SERASUP II allowed a 90 % reduction of the serum amount while maintaining a correct long-term growth. The production of Poliovirus strains 1 and 2 is improved in the extender containing medium, while it is strongly decreased for strain 3.

关键词： POLIOVIRUS PROTEINASE-3C   POLYMERASE-III TRANSCRIPTION   TRANSCRIPTIONAL INHIBITION   TRANSCRIPTION FACTOR-IIIC  

摘要： In HeLa cells, RNA polymerase III (pol III)-mediated transcription is severely inhibited by poliovirus infection. This is due primarily to a reduction in the transcriptional activity of TFIIIC, a transcription factor which binds in a sequence specific manner to the internal promoter of pol III genes. Using gel retardation assays, we have shown previously that inhibition of pol III transcription by poliovirus is correlated with disappearance of a transcriptionally active form of TFIIIC (complex I) concomitant with the appearance of a faster mobility, transcriptionally inactive form of TFIIIC (complex III). We show here that a poliovirus with a point mutation in the proteinase 3C (3C(pro)) region failed to produce complex III and is limited in its ability to inhibit pol III transcription compared with the wild-type virus. Incubation of purified 3C(pro), expressed in Escherichia coli, with transcriptionally active TFIIIC (complex I) in vitro resulted in generation of the transcriptionally inactive complex III form of TFIIIC. In an in vitro transcription assay, treatment of the complex I form of TFIIIC with 3C(pro) almost completely inhibited pol III transcription. Finally expression of the 3C(pro) gene in transfected HeLa cells resulted in significant inhibition of pol III-mediated transcription. The results presented here suggest that proteolysis of the transcriptionally active form of TFIIIC by poliovirus 3C(pro) is a mechanism by which poliovirus inhibits host cell RNA pol III transcription.

关键词： Humans   India   Poliovirus Vaccine, Inactivated/immunology   Poliovirus Vaccine, Oral/adverse effects   Poliovirus Vaccine, Oral/immunology   Vaccines, Inactivated/immunology  

关键词： Oral poliovirus vaccines   Dosage   Poliomyelitis   Poliovirus   Developing countries   Antibodies   Inactivated poliovirus vaccines   Infants  

摘要： Although rates of seroconversion following administration of trivalent oral poliovirus vaccine (TOPV) approach 100% in industrialized countries, only 73% (range, 36%-99%) and 70% (range, 40%-99%) of children in developing countries have detectable antibody to poliovirus types 1 and 3, respectively, after three doses. While factors accounting for these differences have not been fully elucidated, available data suggest that type 2 vaccine virus and enteric pathogens often interfere with responses to types 1 and 3 vaccine viruses but that this interference may be overcome by modifying the absolute and relative dosage of the three Sabin types. Increasing the interval between doses beyond 30 days may also be important, in view of the prolonged excretion of vaccine virus and the potential for interference with responses to subsequent doses. Although advances in molecular biology may ultimately lead to the development of more-immunogenic vaccine candidates, approaches such as increasing the number of doses of TOPV, mass vaccination campaigns, and combined use of oral and inactivated vaccines should also be considered.