ISSN:0300-5526    

DOI:10.1159/000149313

出版商:S. Karger AG    

年代:1982

数据来源: Karger

摘要:

Biophysical and biochemical analysis of hepatitis A virus has shown it to be a 27- to 32-nm icosahedral particle with 32 capsomers. The mature virion has a buoyant density of 1.33–1.34 g/cm3, a sedimentation coefficient of 156–160S, and is composed of four polypeptides with molecular weights of 30,000–33,000 (VPl), 24,000–27,000 (VP2), 21,000–23,000 (VP3), and 7,000–14,000 (VP4). The genome of hepatitis A virus consists of a single piece of single-stranded RNA which sediments at 32–35S and has a buoyant density of 1.64 g/cm3. The molecular weight of RNA is 2.25 × 106 when measured under nondenaturing conditions and 2.8 × 106 when measured under fully denaturing conditions. The genome contains a 40–80 nucleotide sequence of polyadenylic acid and is capable of infecting cell cultures. These findings, together with the observation that the virion is stable at pH 3.0 and resistant to ether and a temperature of 60° for 1 h, indicate that hepatitis A virus should now be classified as an Entero-virus within the family

ISSN:0300-5526    

DOI:10.1159/000149314

出版商:S. Karger AG    

年代:1982

数据来源: Karger

摘要:

The preliminary characterization of four temperature-sensitive (ts) mutants of the O1 Caseros strain of foot-and-mouth disease virus is described. Two mutants, ts 6 and ts 40, showed a very low RNA synthesis rate at nonpermissive temperature and were classified phenotypically as RNA(–). Shift-up experiments demonstrated an incapacity to organize the RNA replicative process at nonpermissive temperature. Another mutant (ts 139) behaved phenotypically as RNA( + ) and its virions were more thermolabile than the wild type virus, so the defect in this mutant is likely to be in one of its structural proteins. Finally, mutant ts 5 was phenotypically RNA( + ); its leak production at nonpermissive temperature was high, and the shift-up experiment showed a defect that was expressed either late in the replicative cycle or continuousl

ISSN:0300-5526    

DOI:10.1159/000149315

出版商:S. Karger AG    

年代:1982

数据来源: Karger

摘要:

The developmental sequence of a neurotropic strain (JHM) of mouse hepatitis virus was examined by transmission electron microscopy and immunocytology. The nucleo-protein core of this coronavirus, which contains RNA of positive polarity and is helical in configuration, becomes incorporated into enveloped particles in the same manner as the nucleocapsids of the orthomyxo- and paramyxoviruses. However, JHM virus is assembled intracellularly by budding at surfaces of smooth membranous vacuoles. A comparison of JHMvirus replication in L2 and 17C1-1 cell lines revealed that L2 cells undergo more rapid cytopathology and cease virus production much sooner than 17C1-1 cells. In L2 cells the accumulation of core material appears to continue after the abrupt cessation of virus assembly. This is evident by the massive cytoplasmic accumulation of structures resembling nucleocapsids, which react with hybridoma antibody to the nucleocapsid antigen as demonstrated by the immunoperoxidase procedure. The current findings are consistent with our previously published demonstration, using cells of neural and other deviation, of the fundamental role of the host cell type in regulating the replication and expression of coronaviruses.

ISSN:0300-5526    

DOI:10.1159/000149316

出版商:S. Karger AG    

年代:1982

数据来源: Karger

摘要:

Six terms are recommended to describe the techniques applied and the effects observed when antibody/virus particle interactions are examined in the electron microscope. These are: immunoelectron microscopy, immunosorbent electron microscopy, antiserum- (or antibody-)coated grids, trapping, clumping and antibody coating. These recommendations are intended to assist authors and editors alike, by decreasing the confusion resulting from the use of a wide variety of alternative terms.

ISSN:0300-5526    

DOI:10.1159/000149317

出版商:S. Karger AG    

年代:1982

数据来源: Karger

摘要:

The structural characteristics and intracellular disposition of microtubules present in osteoclasts in Paget’s disease of bone were compared with those of nucleocapsids in cells infected with measles virus and respiratory syncytial virus (RSV). The distribution of microtubules in pagetic osteoclasts closely paralleled that of measles nucleocapsids in monkey kidney cells, but the dimensions of the pagetic microtubules were significantly different from those of measles virus. In contrast, pagetic microtubules were not distinguishable in dimensions from RSV nucleocapsids but were dissimilar in their conformation and location. The observations support the hypothesis that Paget’s disease of bone is a slow virus disease and suggest that the virus is a pneumovirus (RSV) rather than a morbillivirus (measl

ISSN:0300-5526    

DOI:10.1159/000149318

出版商:S. Karger AG    

年代:1982

数据来源: Karger

摘要:

The amino acid compositions of the virion proteins of several tobamoviruses isolated in China were determined. A classification computed from these and published data of other tobamoviruses was compared with published data of their relatedness assessed using the cDNA: RNA molecular hybridization technique. The classifications are clearly congruent; that based on amino acid composition appears to be best for determining the hierarchical relationships of members within a taxonomic group, rather than for distinguishing between closely related members, whereas nucleic acid hybridization unequivocally places a virus into the appropriate subgroup but is less useful for determining distant relationships.

ISSN:0300-5526    

DOI:10.1159/000149319

出版商:S. Karger AG    

年代:1982

数据来源: Karger

摘要:

5 patients with primary genital herpes simplex virus (HSV) infection were studied prospectively for the production of serum antibody reactivity as measured by the virus micro-neutralization test (NT), micro-solid phase radioimmunometric assay (micro-SPRIA), and antibody-dependent cellular-cytotoxic (ADCC) test. ADCC antibody was detected before reactivity measured by either NT or micro-SPRIA in 2 of the 5 patients. A 3rd patient failed to produce neutralizing antibody, whereas specific activity was detected by the other two methods. In 2 other patients a good correlation was observed for development of antibody by all three methods. There were several discordant results in the kinetics of production of antibody detected by these assays, suggesting that not all individuals produce similar types of antiviral antibody.

ISSN:0300-5526    

DOI:10.1159/000149320

出版商:S. Karger AG    

年代:1982

数据来源: Karger