摘要:

The family Bunyaviridae comprises over 200 viruses (serotypes, subtypes, and varieties) that infect vertebrates and/or invertebrates. Four genera of viruses have been defined (Bunyavirus, Nairovirus, Phlebovirus, and Uukuvirus). The main characteristics of the member viruses are: (i) the virus particles are for the most part uniformly spherical, 80–110 nm in diameter, and possess a unit membrane envelope from which protrude polypeptide spikes 5–10 nm long; (ii) the viruses have three helical nucleocapsids, often in the form of supercoiled circles, each consisting of a single species of single-stranded RNA, a major nucleocapsid polypeptide, N, and at least in some cases minor amounts of a large polypeptide which may be a transcriptase component; (iii) the genome is composed of three species of RNA (L, large; M, medium; and S, small), organized in end-hydrogen bonded circular structures; (iv) most viruses have three major virion polypeptides (N, and two surface polypeptides, designated Gl and G2); (v) for at least some member viruses, the virions have been shown to contain an RNA-directed RNA polymerase, believed to be responsible for the synthesis of viral complementary mRNA, so that bunyaviruses are considered to be negative-stranded viruses; (vi) at least some bunyaviruses are capable of heterologous virus genome segment reassortment and can form recombinant viruses at high or low frequency; (vii) viruses appear to mature primarily at smooth membrane surfaces and accumulate in Golgi vesicles and saccules, or nearby; (viii) transovarial, venereal and/or transstadial transmission in arthropods has been shown to occur for some members of the fam

ISSN:0300-5526    

DOI:10.1159/000149174

出版商:S. Karger AG    

年代:1980

数据来源: Karger

摘要:

Serological relationships among viruses of the Nairovirus genus, family Bunyaviridae, were investigated. Relationships were found among viruses of the following serogroups: Congo-Crimean hemorrhagic fever, Nairobi sheep disease, Dera Ghazi Khan, Bandia, and Hughes.

ISSN:0300-5526    

DOI:10.1159/000149175

出版商:S. Karger AG    

年代:1980

数据来源: Karger

摘要:

Five antigenically distinct serotypes of human papillomavirus (HPV) cause various cutaneous verrucae with distinct clinical features. Laryngeal and other mucosal papillomas, also suspected to have a viral etiology, were examined for the presence of a genus-specific (common) antigen of HPV using a peroxidase-antiperoxidase (PAP) technique. The primary antiserum used was reactive against laryngeal papillomas from 26 of 35 randomly selected patients (74%); overall, 49 of the 102 squamous papillomas stained were positive for HPV (48%). HPV antigen was not demonstrated within frankly dysplastíc squamous cells. Nuclear localization of virus was confirmed by electron microscopy in 3 cases positive for HPV. PAP localization of HPV is rapid and more efficient than routine electron microscopy. Our data indicate a common pathogenesis for some papillomas and cutaneous verrucae and suggest a future role for immunohistochemistry in evaluating the epidemiology and pathobiology of laryngeal papillomatosis

ISSN:0300-5526    

DOI:10.1159/000149176

出版商:S. Karger AG    

年代:1980

数据来源: Karger

摘要:

An indirect peroxidase antibody to membrane antigen (IPAMA) technique was applied for determination of immunoglobulin G (IgG) antibody to human cytomegalovirus (CMV). The antigen consisted of air-dried, CMV-infected cells. The results were compared with those obtained with the CMV complement-fixation (CF) test. Comparison of titers obtained by IPAMA with those obtained by CF for sera of 48 healthy adults and 7 CMV patients showed good agreement between the tests. No cross-reactivity with other herpesviruses was observed. There was no problem of nonspecific cytoplasmic reaction with Fc receptors for IgG, even at low serum dilutions. The IPAMA technique appears to be reliable, is easily and rapidly performed, and is recommended as a routine test for serological diagnosis of CMV infections as well as for screening the general population.

ISSN:0300-5526    

DOI:10.1159/000149177

出版商:S. Karger AG    

年代:1980

数据来源: Karger

摘要:

Densonucleosis viruses (types 1 and 2) contain four major structural polypeptides with a total molecular weight in excess of the coding capacity of the DNA. Peptide maps obtained by limited proteolysis of isolated 125I-labeled proteins of both virus types indicate a common origin of the virus proteins and homology between the different viruses. The structure of densonucleosis virus type 2 and its homologous top component (naturally occurring empty particles) was compared by proteolysis using several proteases and the bifunctional cross-linking reagents dimethylsuberimidate (DMS) and dimethylmalonimidate. Similar susceptibilities of both components with proteases were obtained. The top components alone were accessible to the action of the cross-linking reagent DMS. The lowest molecular weight major structural polypeptide was most resistant to the action of the proteases and DMS.

ISSN:0300-5526    

DOI:10.1159/000149178

出版商:S. Karger AG    

年代:1980

数据来源: Karger

摘要:

A purified enzyme mixture obtained by extraction of Aspergillus niger cells with saline was shown to have glycosidase, carboxypeptidase, and endopeptidase activities and to abolish the hemagglutinating and infectious activities of the PR8 strain of influenza virus. The endopeptidase activity of the A.niger extracts was shown to be responsible for inactivation of the virus.

ISSN:0300-5526    

DOI:10.1159/000149179

出版商:S. Karger AG    

年代:1980

数据来源: Karger

摘要:

A BHK/21 cell line persistently infected by an arenavirus is described. During four consecutive passages, 30–45% of the cells showed granular cytoplasmic antigen by indirect immunofluorescence, employing both Argentine hemorrhagic fever convalescent sera and sera from animals immunized with Junin virus. Virus isolated from the cells killed suckling mice but not adult mice and protected guinea pigs against further challenge with the virulent prototype strain of Junin virus. Neutralization tests showed that the virus isolated from the cells was neutralized by anti-Junin virus antisera. The usefulness of this cell line in rapid immuno-fluorescent serological procedures is describe

ISSN:0300-5526    

DOI:10.1159/000149180

出版商:S. Karger AG    

年代:1980

数据来源: Karger

摘要:

A fibroblastic cell line transformed by ts-P155, an early temperature-sensitive mutant of polyoma virus, has been isolated after infection of secondary mouse embryo cells at the restrictive temperature of 39°. These cells, designated Cyp, undergo a massive CPE accompanied by the production of infectious, temperature-sensitive virus when transferred to the nonrestrictive temperature of 33°. Several independent clones were established from cells which survived the induction of virus multiplication occurring at 33°. When routinely cultured at this temperature, these cells, termed R, displayed the growth properties of transformants and produced variable amounts of infectious, temperature-sensitive virus. This shedding of virus could not be ‘cured’ by the addition to the culture medium of antipolyoma serum which had already been found to effectively suppress virus production in Cyp cell cultures transferred to 33°. Moreover, R cells seemed to have developed a resistance to superinfection that the parent Cyp cell line did not exhibit. Therefore, virus production in R cell cultures probably reflects the occasional excision and replication of integrated viral genomes rather than a carrie

ISSN:0300-5526    

DOI:10.1159/000149181

出版商:S. Karger AG    

年代:1980

数据来源: Karger

摘要:

R clones are derived from cells which have survived the induction of virus multiplication in cultures of permissive mouse transformants carrying a temperature-sensitive polyoma virus genome. R cells are transformed cells characterized by the shedding of small amounts of temperature-sensitive, infectious virus and a resistance to superinfection. Immunofluorescence tests and infectious center assays indicated that virus production in R cell cultures probably resulted from the entry, at all times during the growth of the cultures, of a minority of the cell population into a lytic cycle of normal burst-size. Although large T antigen was readily detectable in extracts from R cells, free viral DNA was generally present in small amounts, but free of defective molecules as judged from its susceptibility to restriction enzymes. Resistance toward exogenous polyoma virus is probably due to rather specific changes in the surface of R cells, as indicated by the measurement of two parameters, uptake of whole virus and susceptibility toward transfection by viral DNA. Thus, R cells appeared to escape lysis-from-within because the replication of the endogenous viral genome was rarely being activated, and lysis-from-with-out because exogenous virus was largely unable to invade them.

ISSN:0300-5526    

DOI:10.1159/000149182

出版商:S. Karger AG    

年代:1980

数据来源: Karger

摘要:

Herpesvirus ateles (HVA) can transform lymphocytes from certain nonhuman primates, leading to established lymphoid lines. We have found that HVA adsorbs preferentially to the T lymphocytes (E-rosette-forming cells) of marmoset monkeys and that DNA synthesis is induced within 2–6 days after infectio

ISSN:0300-5526    

DOI:10.1159/000149183

出版商:S. Karger AG    

年代:1980

数据来源: Karger