摘要:

Japanese quail cells transformed by the replication-defective, Bryan high-titer strain of Rous sarcoma virus, BH RSV(-)Q, clone 3, revealed intracytoplasmic A-type particles after dexamethasone treatment. In the absence of dexamethasone, or when super-infected with a helper virus in the presence or absence of dexamethasone, no such particles were observed. Chick embryo cells (CEC) infected with a temperature-sensitive sarcoma virus mutant, LA 334, coordinately defective for transformation and viral replication, showed abnormal accumulation of viral core substances and aberrant budding at the non-permissive temperature (41°). CEC infected with LA 334 and treated with dexamethasone at 41° resulted in more extensive accumulation of abnormal budding without increased release of viral particles. Dexamethasone, however, did not lead to abnormal morphogenesis of virus under permissive conditions. The selective effects of dexamethasone on the morphogenesis of these two mutants of avian sarcoma virus are discusse

ISSN:0300-5526    

DOI:10.1159/000148962

出版商:S. Karger AG    

年代:1978

数据来源: Karger

摘要:

Marek’s disease herpesvirus (MDHV) isolated from chickens free of naturally occurring avian leukosis virus (ALV) infection produced characteristic foci in both chicken embryo fibroblast (CEF) and chicken kidney cell (CKC) cultures. MDHV-A, which was extracted from the feather follicle epithelium of chickens naturally infected with ALV, did not induce cy tologic changes in CEF cultures, but did cause focus formation in CKC cultures. ALV was detected in MDHV-A, but not in MDHV preparations. MDHV-A (reconstructed in vivo) and MDHV were further distinguished from one another by inoculation of ALV-free LSI-SPF chickens. MDHV-A elicited a high incidence of early mortality which was not accompanied by the gross tumor spectrum characteristic of Marek’s disease, although extensive histologic lesions were present. The differences between MDHV and MDHV-A were not as striking in another line of ALV-free chickens (SPAFAS). By contrast, among conventional chickens with naturally occurring ALV infection, neither MDHV-A nor MDHV caused appreciable early mortality although both were highly oncogenic (gross tumor development). These observations demonstrate that the presence of an oncornavirus (ALV), detected by radioimmune but not complement fixation assays, can influence the in vitro and in vivo characteristics of an oncogenic herpesvirus (MDHV). The observations recorded here resolve some of the inconsistencies reported in the literature. Thus, the apparent failure by some to find interactions between MDHV and oncornaviruses can be ascribed to the comparatively limited sensitivity of the complement fixation assay used to detect oncornaviruses (ALV). We have shown that the presence of oncornavirus detectable by radioimmune assay, but not by complement fixation, can influence the in vitro and in vivo responses of an oncogenic herpesvirus (MDHV). Our observations relating to viral interaction do not imply that MDHV required the presence of ALV to produce dise

ISSN:0300-5526    

DOI:10.1159/000148963

出版商:S. Karger AG    

年代:1978

数据来源: Karger

摘要:

Hepatitis A virus was purified from fecal specimens obtained from 3 patients with naturally acquired hepatitis A, by a process of differential centrifugation, chloroform extraction, column chromatography, and isopycnic ultracentrifugation. Analysis of purified virus by discontinuous SDS-PAGE revealed three major polypeptides with molecular weights of 34,000, 25,500, and 23,000 daltons. These polypeptides appear to be specific for hepatitis A virus and have similar molecular weights to three of the four major polypeptides reported for members of the genus Enterovirus within the family Picornaviridae.

ISSN:0300-5526    

DOI:10.1159/000148964

出版商:S. Karger AG    

年代:1978

数据来源: Karger

摘要:

Studies of the Fc receptor induced by herpes simplex virus using the 7S EA rosette assay reveal that (i) the percentage of cells showing receptor activity is multiplicity-dependent; (ii) the percentage of cells rosetting is independent of the cell cycle phase of the host cell; (iii) RNA and viral protein synthesis, and probably glycosidation, are required for the induction of the receptor but not viral DNA synthesis; and (iv) the receptor is neuraminidase-resistant but trypsin-sensitive.

ISSN:0300-5526    

DOI:10.1159/000148965

出版商:S. Karger AG    

年代:1978

数据来源: Karger

摘要:

A simple method for rapid identification and subtyping of herpes simplex virus from clinical specimens is presented. Inoculated cultures demonstrating cytopathic changes were treated with type-specific cytotoxic antisera against herpes simplex virus and complement. Lysis of cells was revealed by staining with trypan blue. The technique allowed identification and subtyping of herpes simplex virus within 2 h after the appearance of CPE.

ISSN:0300-5526    

DOI:10.1159/000148966

出版商:S. Karger AG    

年代:1978

数据来源: Karger

摘要:

Particles resembling togaviruses were observed by electron microscopy in the urinary bladder lamina propria of one capuchin monkey and in placental syncytiotrophoblasts of one baboon. Type C viruses were observed in the baboon placenta, but not in the tissues of the capuchin monkey.

ISSN:0300-5526    

DOI:10.1159/000148967

出版商:S. Karger AG    

年代:1978

数据来源: Karger

摘要:

San Miguel sea lion virus (SMSV) is indistinguishable from vesicular exanthema virus (VEV) and feline calicivirus (FCV) in its morphology and in possessing a single capsid polypeptide with a molecular weight of approximately 65 × 103. Neutralization tests readily differentiate the three viruses, but immunodiffusion tests show that SMSV is closely related serologically to VEV but not to FCV. Although the RNAs of the three caliciviruses have similar base compositions, homology tests show that SMSV is closely related to VEV but is not related to FCV. Tryptic peptide maps of the single major polypeptide comprising the capsid of each virus also show that SMSV and VEV are more closely related to each other than to FCV

ISSN:0300-5526    

DOI:10.1159/000148968

出版商:S. Karger AG    

年代:1978

数据来源: Karger

摘要:

Experimental transmission of non-A, non-B hepatitis was apparently accomplished in 5 chimpanzees following inoculation with presumably infectious human sera. Administration of sera from implicated donors with normal alanine aminotransferase (ALT) values, as well as from those with abnormal ALT levels, resulted in the development of ALT abnormalities in the inoculated chimpanzees. Transmission from donors with normal ALT values implies that healthy carriers of non-A, non-B virus exist. Evidence is presented which indicates that a period of viremia precedes the clinical illness by at least 12 days.

ISSN:0300-5526    

DOI:10.1159/000148969

出版商:S. Karger AG    

年代:1978

数据来源: Karger