摘要： 电子显微学金标记技术是将电镜技术同免疫学及免疫细胞化学相结合而发展起来的一项新技术。本研究将此技术同时应用于液体样品及感染细胞中脊髓灰质炎等病毒抗原的标记，对反应物混合法同悬浮法、低温包埋同常规包埋金标记以及标记条件、反应物浓度等不同条件下的标记结果进行了摸索和比较。结果表明，应用反应物混合法，并适当控制琼脂扩散时间及反应物浓度，可获得低背景金标记结果，该方法可广泛应用于液体标本中各种病毒抗原特别是小球形病毒的标记，具有明显提高病毒检出率和检出速度的特点。低温包埋超薄切片金标记能较好地保存抗体活性，比其他标记方法更适合于感染细胞中病毒抗原的标记，只要认真注意各反应浓度、稀释及清洗用缓冲液的选择以及适当地清洗，能得到高特异性标记及低背景污染的标记效果，可作为病毒形态发生学研究的首选方法。 应用低温包埋超薄切片金标技术，对脊髓灰质炎病毒的形态发生学及病毒感染后所引起的细胞超微病理形态变化进行了研究。病毒感染后不同时期的细胞形态学变化主要是细胞质内大量的小体、小泡形成。在该病毒的形态发生学方面，观察到以下特殊现象；小体来源于细胞核，它是在扩张的核被膜中，由内层核膜向外突起芽生形成，形成的小体经过同核周池局部融合的内质网池迁移至胞质中；进入胞质中的小体同胞质内小泡密切接触，共同与病毒复制；致密斑同小体及小泡在形态上有密切联系，病毒在此区域内复制，因此，将它们称为脊髓灰质炎病毒的复制复合体。 通过对上述现象形态学观察及金标记实验的进一步研究表明，细胞核参与脊髓灰质炎病毒的复制，该过程是通过核突出物小体由细胞核到细胞质的迁移来实现的。

关键词： 脊髓灰质炎   小儿麻痹   肠道病毒感染   接种者   OPV   粘膜   生物膜   疫苗   菌苗  

摘要： 作者用单价口服脊髓灰质炎病毒疫苗（OPV）1型病毒高、低两种剂量分别攻击经OPV和增效灭活的脊髓灰质炎疫苗（E-IPV）初免的幼儿,比较其咽部和胃肠道的粘膜免疫力。试验对象是在2、4和18月龄时接种过OPV（79人）或E-IPV（93人）的20～30月龄的幼儿,按口服单价1型OPV的剂量分成两组,其中一组服500 TCID;,另一组服500000TCID;。取攻击前及攻击后第3、7、14、21、42天的咽部及粪便样品,旧标准方法处理样品在Vero细胞上培养,用型特异性鼠或马抗

摘要： 为了评价冷链运转工作状态,我们于1988年开始,连续三年进行了对温度敏感的三价脊髓灰质炎减毒活疫苗(TOPV)效力检测。一、方法

摘要： Poliovirus RNA encodes an RNA-dependent RNA polymerase, designated 3D(pol) that catalyzes the synthesis of both plus and minus strand viral RNA. This enzyme was purified to near homogeneity from poliovirus-infected HeLa cells, recombinant baculovirus-infected insect cells, and from Escherichia coli transformed with an expression plasmid containing poliovirus 3D sequences. The two recombinant expression systems produced significantly higher yields of active enzyme than could be attained from virus-infected HeLa cells. All preparations contained a 52-kDa protein, recognized by antisera raised against 3D expressed as a fusion protein in E. coli. Immunoreactive protein resolved into 3-4 species on isoelectric focusing sodium dodecyl sulfate-polyacrylamide gel electrophoresis two-dimensional gels. Efforts to demonstrate that the multiple spots resulted from phosphorylation were negative. Furthermore, no evidence for autophosphorylation of purified 3D(pol) was obtained. Purified 3D(pol) from recombinant sources manifested the same specific activities as enzyme from poliovirus-infected HeLa cells in both a poly(A)-dependent poly(U) polymerase assay and a poliovirus RNA-dependent RNA polymerase assay. The products of the latter reaction reached the length of the template (7.5 kilobases) in 20-30 min, indicating an elongation rate of approximately 300 nucleotides/min at 30-degrees-C. No products exceeded the length of the template. Intermediate length products were detected, which presumably resulted from pauses in transcription due to template structure. All transcription was dependent on primer. The kinetic parameters of all three purified enzyme preparations were the same;the K(m) for UTP was 2-4 +/- 0.1-mu-m in an RNA polymerase activity assay. Product formation was linear for up to 45 min, except for a 35 min lag before synthesis began. The lag was independent of enzyme concentration, and independent of the template used. The lag was eliminated by preincubating enzyme,

关键词： Poliovirus   HeLa cells   Complementary DNA   Virions   Polymerase chain reaction   Viral RNA   Gels  

摘要： Cell-free translation of poliovirus RNA in an extract of uninfected human (HeLa) cells yielded viral proteins through proteolysis of the polyprotein. In the extract, newly synthesized proteins catalyzed poliovirus-specific RNA synthesis, and formed infectious poliovirus de novo. Newly formed virions were neutralized by type-specific antiserum, and infection of human cells with them was prevented by poliovirus receptor-specific antibodies. Poliovirus synthesis was increased nearly 70-fold when nucleoside triphosphates were added, but it was abolished in the presence of inhibitors of translation or viral genome replication. The ability to conduct cell-free synthesis of poliovirus will aid in the study of picornavirus proliferation and in the search for the control of picornaviral disease.

关键词： 病毒类型   病毒污染   生活废水   溶解氧浓度   自来水厂   肠道病毒   人类疾病   江河湖泊   轮状病毒   脊髓灰质炎病毒  

摘要： 环境中有哪些引起人类疾病流行的病毒类型?它们的分布、传播途径有什么规律?它们与人类健康的关系如何?怎样使它们得以控制和消除?对这些问题的了解,有助于增进人们对病毒污染环境所造成严重后果的认识及其防治对策的选择。

关键词： VACCINE-ASSOCIATED POLIOMYELITIS   POLIOVIRUS RECOMBINANTS   SEROTYPE-2 SPECIFICITY  

摘要： Five representatives from a collection of 21 Sabin type 2-like poliovirus strains isolated from paralytic poliomyelitis cases in two regions of the USSR have been subjected to limited nucleotide sequencing. All proved to be intertypic recombinants having the genes encoding capsid proteins of Sabin 2 origin and a 3'-end portion of the genome derived from either type 1 (3 isolates) or type 3 (2 isolates) Sabin strains. The crossover points in all the 5 genomes have been mapped to different loci of the P3 region. At least 6 additional isolates from the same collection (and 2 isolates from healthy contacts), appeared to have a type 2/type 1 recombinant genome, as judged by oligonucleotide mapping. The biological significance of frequent occurrence of recombinants among field isolates of vaccine-related strains is discussed.

摘要： The picornavirus 3C proteinases are substrate-specific thiol proteases that have been shown by secondary structure predictions and protein modeling studies to be similar to the trypsin-like serine proteases. We have examined several mutations of the 3C proteinase at putative active site and non-active site residues. The effect on 3C-mediated protein processing supports the model of serine protease similarity. In particular, we have shown that 3C can utilize a serine at position 147, which is predicted to supply the nucleophilic residue of the catalytic triad. We suggest that picornavirus 3C proteinases may represent a class of enzymes that have maintained the catalytic mechanism characteristic of a proposed enzyme ancestral to the highly divergent class of serine proteases.