Antigen and antibody in Aleutian disease in mink. II. The reaction of antibody with the Aleutian disease agent using immunodiffusion and immunoelectroosmophoresis.
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Aleutian disease viral (ADV) antigen was prepared by fluorocarbon extraction of spleen, liver, and lymph nodes from mink experimentally infected ten days previously. Using a potent ADV antigen, antibody was detected by immunodiffusion (ID) and immunoelectroosmophoresis (IEOP). Utilizing these precipitin tests, antibody was detected in all the mink sera tested as early as seven days after experimental infection. Titer of antibody increased throughout the infection period. Titers of more than 100 were reached by 15 days post infection, titers of 1,000 at one month, and titers of more than 5,000 to 10,000 were achieved at two months post infection and thereafter. The immunodiffusion test gave similar or slightly lower titers than those detected by the IEOP. The IEOP test promises to be a most useful technique for the diagnosis of aleutian disease because it is simple, rapid and specific and is capable of detecting infection early in the course of the disease. It is suggested that this test should be utilized especially for the screening of animals purchased or imported as breeding stock onto ranches. (+info)
Previously unrecognized virus from submaxillary glands of gnotobiotic and conventional rats.
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Ashe, Warren K. (National Institute of Dental Research, Bethesda, Md.), Henry W. Scherp, and Robert J. Fitzgerald. Previously unrecognized virus from submaxillary glands of gnotobiotic and conventional rats. J. Bacteriol. 90:1719-1729. 1965.-A serially transmissible cytopathic agent was isolated from histologically normal submaxillary glands, but not from various other tissues or specimens, from 74 of 97 gnotobiotic and conventional rats. Triturates of the glands or subsequent culture supernatant fluids induced specific cytopathic effects (CPE) in monolayer cultures of primary rabbit kidney cells (14 passages), a line of human skin cells (8 passages), and HeLa cells (17 passages). Transfer of supernatant fluids containing infected cells enhanced transmissibility. Neutralization of the CPE was demonstrated with sera of gnotobiotic and conventional rats and with homologous rabbit antiserum. A cold hemagglutinin specific for rabbit erythrocytes is associated with, but separable from, the infectious particle. Cultures of the agent induced no discernible effect on inoculation by various routes into suckling, weanling, or adult conventional mice, rats, and hamsters. Weanling and adult rabbits were also unaffected. Cultures for bacteria in gland extracts and infected cell supernatant fluids were uniformly negative. Negative cultures on PPLO media and negative arginine deiminase tests indicated that this agent is not a Mycoplasma. The data indicate that it is a virus whose biological and physical properties distinguish it from the known cytomegaloviruses. Because it has been found so far only in rat submaxillary glands, this agent is designated provisionally as RSMG virus. (+info)
In vitro studies on the antiviral activity of 1, 3-bis(2-chloroethyl)-1-nitrosourea.
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Chemotherapy experiments carried out in vitro demonstrated that 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) was active against lymphocytic choriomeningitis virus and had an equivocal antiviral effect on Semliki Forest, herpes simplex, and vaccinia viruses. No antiviral effect was observed with BCNU against western equine encephalomyelitis, polio, and parainfluenza (HA-1) viruses. Activity of the drug was determined by inhibition of viral-induced cytopathogenic effect in KB or chick embryo cells and by reduction of virus titer in cell culture supernatant fluid. Maximal activity against the viruses was observed when drug and virus were incubated together for 30 min prior to addition to cells; essentially no activity could be demonstrated if BCNU and virus were added to cells with no prior incubation. (+info)
Characterization of bluetongue virus ribonucleic acid.
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An improved purification procedure yielded bluetongue virus free from any single-stranded ribonucleic acid (RNA) component. Double-stranded RNA obtained from purified virus or isolated from infected cells was fractionated into 5 components by means of sucrose gradient sedimentation analysis, and into 10 components by electrophoresis on polyacrylamide gels. The size of these components vary from 0.5 x 10(6) to 2.8 x 10(6) daltons, with a total molecular weight estimate of about 1.5 x 10(7) for the viral nucleic acid. The denaturation of the genome and separation of the resulting fragments are also discussed. (+info)
Characterization of the Kilham rat virus.
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Kilham rat virus (KRV) was found to grow in a rat nephroma cell line and to form plaques on secondary rat embryo monolayers. The virus was purified by enzymatic treatment and isopycnic cesium chloride sedimentation. KRV bands at a density of 1.41 g/cm(3) in cesium chloride. It contains about 26.5% deoxyribonucleic acid (DNA). The sedimentation coefficient S(20,w) in sucrose gradients was 122 corresponding to a molecular weight of 6.6 x 10(6) daltons. The reaction of formaldehyde with the KRV virion suggests that the DNA in situ is single-stranded. DNA extracted from KRV had a buoyant density of 1.715 g/cm(3) in cesium chloride. The S(20,w) was determined in sucrose gradients to be 16, and the molecular weight was calculated to be approximately 1.7 x 10(6) daltons. The base composition of the DNA is 26.7% adenine, 30.8% thymine, 20.0% guanine, and 22.5% cytosine. On the basis of its noncomplementary nucleotide ratio, melting curve, and the reaction with formaldehyde, the DNA of KRV is believed to be single-stranded. (+info)
Ultrastructural comparison of a virus from a Rhesus-monkey mammary carcinoma with four oncogenic RNA viruses.
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The ultrastructure and morphogenesis of Mason-Pfizer monkey virus, isolated from a mammary carcinoma in a Rhesus monkey, was compared with those of murine mammary tumor virus, murine leukemia virus, L1210 leukemia-associated virus, and avian myeloblastosis virus. The simian virus resembled murine mammary tumor virus and the L1210 virus in that it produced intracytoplasmic particles that were enveloped during budding. It resembled L1210 virus and murine leukemia virus in budding with smooth envelopes. It differed from all the others in being more fragile. These similarities, combined with biochemical characteristics reported elsewhere in this issue, suggest that the monkey virus is an oncogenic RNA virus. (+info)
Linear, single-stranded deoxyribonucleic acid isolated from Kilham rat virus.
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Kilham rat virus (KRV) was grown in a rat nephroma cell line and was purified by two isopycnic centrifugations in cesium chloride. The virus contains single-stranded deoxyribonucleic acid (DNA) with a molecular weight of approximately 1.6 x 10(6). The DNA was extracted from the virion by both phenol extraction and by 2% sodium dodecyl sulfate at 50 C. KRV DNA, extracted by both procedures, was observed in an electron microscope by using a cytochrome c or diethylaminoethyldextran monolayer. The DNA was also exposed to exonuclease I, an enzyme which hydrolyzes specifically linear, single-stranded DNA. Hydrolysis of 70 to 80% of the DNA was observed. Both the enzymatic and the electron microscope studies support the conclusion that extracted KRV DNA is a single-stranded, linear molecule. The length of the DNA was measured in the electron microscope and determined to be 1.505 +/- 0.206 mum. (+info)
Comparison of the ribonucleic acid polymerases of two rhabdoviruses, Kern Canyon virus and vesicular stomatitis virus.
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A ribonucleic acid (RNA)-dependent RNA polymerase has been demonstrated in Kern Canyon virus (KCV) particles. The RNA product of the KCV polymerase hybridizes to KCV viral RNA. The properties of this viral enzyme have been characterized and compared with those of vesicular stomatitis virus (VSV). RNA polymerases from both viruses require similar conditions of temperature, pH, and detergent and magnesium concentrations for maximal synthesis of RNA. The RNA polymerase contained in the virion of KCV was more dependent on the presence of a sulfhydryl agent than was the VSV enzyme. Under optimal conditions, the specific activity of the VSV polymerase is about twenty-five times as great as that of KCV. (+info)