摘要:

A labile subviral particle (‘the equestron’) is proposed as a multifunctional regulator of poliovirus growth, withaffinities for 45s ribosomal subunits and 5’ ends of viral RNA. These suggested properties suffice to explain suppression of hostprotein synthesis, synchronous synthesis of viral RNA and protein, and timing of maturation. The candidate for the equestron is a precursor to the virionstructural

ISSN:0300-5526    

DOI:10.1159/000148826

出版商:S. Karger AG    

年代:1973

数据来源: Karger

摘要:

A noninfectious hamster C-type oncornavirus (D9) associated with a spontaneous hamster lymphoma was characterized. The defective virions contained 70S RNA and the base composition was similar to that of a murine sarcoma-leukemia virus. With both endogenous and added templates, the virions were found to be deficient in DNA polymerase activity. These results suggest that DNA polymerase may be required for D9 infectivity.

ISSN:0300-5526    

DOI:10.1159/000148827

出版商:S. Karger AG    

年代:1973

数据来源: Karger

摘要:

Sixteen cultures of continuous human cell lines were tested for oncornaviruses. Six cultures spontaneously released theviruses into the culture fluid. Five cultures released the virusesafter treatment with 5-bromodeoxyuridine or mitomycin C. Five cultures were negative. The viruses belonged to the B and Ctypes of oncornaviruses. Possible origin of the viruses is discussed.

ISSN:0300-5526    

DOI:10.1159/000148828

出版商:S. Karger AG    

年代:1973

数据来源: Karger

摘要:

Both 35S and 20S viral RNA species from transformed rat cells which produce the murine sarcoma-leukemia virus complex were retained on nitrocellulose membrane filters, yielding a 33-fold purification and over a 50 % recovery of virus-specific RNA. These findings suggest that intracellular 35S and 20S RNA species contain poly(A) tracts.

ISSN:0300-5526    

DOI:10.1159/000148829

出版商:S. Karger AG    

年代:1973

数据来源: Karger

摘要:

RNA synthesis in larvae of Bombyx mori was examined by theincorporation of 32P into purified single- and synthesis double-stranded RNAs. In larvae infected with a cytoplasmic polyhedrosis virus (CPV), both single- and double-stranded RNA were synthesized after pre-treatment with 10 µg actinomycin D. Approximately 70 % of the single-stranded RNA synthesized in these larvae re-annealed with heat-denatured RNA extracted from purified virions of B. mori CPV. It did not self-anneal, nor did it anneal significantly with RNA from Arctia caja CPV, or from B. morilaτvae. This suggested that the single-stranded RNA is largely virus-specific and represents viral messenger RN

ISSN:0300-5526    

DOI:10.1159/000148830

出版商:S. Karger AG    

年代:1973

数据来源: Karger

摘要:

By heating neutralized mixtures of type 1poliovirus and antibody at 50° in 2 m Cad 2 or MgCl2, the virus could be dissociated from its antibody, and 100 %recovery of infectious virus could be achieved. Heating alone was not responsible for this phenomenon, sincecystine-stabilized thermoresistant polioviruses could not be recovered from neutralized mixtures by 50° treatment. Only 10 % recovery was achieved with other enteroviruse

ISSN:0300-5526    

DOI:10.1159/000148831

出版商:S. Karger AG    

年代:1973

数据来源: Karger

摘要:

Three methods were compared for sensitivity and specificity in detecting rubella IgM antibody in early sera from post-natal infections and in sera from congenital infections. treatment pro-Mercaptoethanol duced a significant reduction in hemagglutination-inhibiting antibody titer in only 2 of 20 sera, but sucrose density centrifugation and indirect fluorescent antibody staining with an anti-IgM conjugate demonstrated rubella IgM antibody in all 20 sera. None of the methods detected rubella IgM antibody at a titer of 1:8 or greater in 10 sera from long-past infections. The anti-IgM conjugate appeared to be somewhat less specific than the anti-IgG conjugate from the same commercial source. It gave low FA staining titers with a number of 7S gradient fractions which could not be shown to contain IgM by immunodiffusion or immunoelectrophoresis; the anti-IgG conjugate did not stain 19S gradient fractions unless they were shown to be contaminated with IgG. Anti-IgM conjugates from 4 different commercial sources were found to vary widely in their ability to detect rubella IgM antibody. The sensitivity of FA staining for detection of IgM antibody was also affected by the time and temperature of incubation, and the specificity of sucrose density gradient centrifugation by the volume of fractions collected and the time of centrifugation.

ISSN:0300-5526    

DOI:10.1159/000148832

出版商:S. Karger AG    

年代:1973

数据来源: Karger

摘要:

A 2½-year-old boy was severely bitten April 1 1969, by a rabid bobcat in San Diego, Calif. He was promptly treated with duck embryo rabies vaccination but not with rabies antiserum. Clinical rabies developed April 18, but with intensive hospital care he survived 133 days after onset of symptoms. Virus could not be isolated from stool, throat, urine, cerebrospinal fluid, saliva, brain biopsy tissue, or from autopsy tissues, probably due to neutralization of virus by antibody, but the diagnosis of rabies was proven by the extremely high rise in rabies antibody titer and by fluorescent antibody staining of brain biopsy tissue. Optimal rabies preventive treatment should be given to all exposed individuals, but if clinical rabies develops, intensive supportive treatment should be given, since survival of at least some cases may be possible. Careful virologic and serologic studies, undertaken as early as possible, are especially important to differentiate rabies from rabies vaccine reaction, and to fully document recovery from rabies should this occur

ISSN:0300-5526    

DOI:10.1159/000148833

出版商:S. Karger AG    

年代:1973

数据来源: Karger