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At least 19 recordsLinked to original sources
PubMed1977

Comparison of primary rhesus and cynomolgus monkey kidney cell cultures for viral isolation from clinical specimens.

Rhesus monkey kidney and cynomolgus monkey kidney cell cultures were compared for viral isolation by using clinical specimens that yielded 203 viral isolates. Cynomolgus and rhesus monkey kidney cells were comparable for the isolation of 22 adenoviruses, 12 coxsackieviruses, and one poliovirus. Four of 50 echoviruses and seven of ten herpesviruses were detected only in cynomolgus monkey kidney cells. Influenza virus was isolated in 84 instances, of which eight were detected only in rhesus and four only in cynomolgus monkey kidney cells. Rhesus monkey kidney cells yielded six more parainfluenza virus isolates. Except possibly for parainfluenza virus, cynomolgus monkey kidney cells appear to be as sensitive as rhesus monkey kidney cells for viral isolation from clinical specimens.

Animals↗
PubMedDate not supplied

Infectious tenosynovitis (viral arthritis): characterization of a Connecticut viral isolant as a reovirus and evidence of viral egg transmission by reovirus-infected broiler breeders.

Connecticut isolant S1133 of tenosynovitis was characterized as a reovirus by physicochemical, biological, and morphologic studies. After inoculation of 35-week-old broiler breeders with tenosynovitis virus by subcutaneous route, virus was found in embryos of eggs laid by the breeders during a period of 8 to 12 days after inoculation.

Animals↗
PubMed1979

In vivo infectivity of the fibrotropic C-type viral isolates from C57BL/Ka mice.

Of the three fibrotropic C-type viral isolates from C57BL/Ka mice, only the BL/Ka(B) virus is capable of infecting normal hematopoietic and lymphoid cell populations of C57BL/Ka mice in vivo, and none are tumorigenic. Inoculation of this virus alone into neonates resulted in transient replication in the bone marrow, spleen, and occasionally the thymus. Thymocytes could, however, be permanently infected in such animals if BL/Ka(B) were coinoculated with the xenotropic BL/Ka(X) virus. Neonatal injection of BL/Ka(B) prior to fractionated wholebody irradiation yielded an increase in the percentage of virus-productive radiogenic lymphomas and a decrease in incidence of such tumors. Injection of BL/Ka(B) into normal adult C57BL/Ka mice did not yield overt expression of virus replication in any of the tissues tested; latent infection could, however, be detected in the marrow and in the reticuloepithelium of the thymus. Whole-body X-irradiation of adults with 400 rads partially restored the neonatal susceptibility of bone marrow cells to infection by the isolate. BL/Ka(B) injection after fractionated whole-body irradiation of weanling C57BL/Ka mice increased the percentage of virus-positive lymphomas and revealed that a bone marrow cell subpopulation permissive for infection by the virus increases greatly in abundance soon after irradiation.

Animals↗
PubMed1975

Infectious bovine rhinotracheitis-infectious pustular vulvovaginitis viral isolates from cattle with epididymitis and vaginitis.

Infectious bovine rhinotracheitis-infectious pustular vulvovaginitis (IBR-IPV) viral isolates were obtained from cattle affected with epididymitis-vaginitis. Isolation of virus from the diseased animals indicated that the genital form of IBR-IPV virus infection exists in Kenya and that epididymitis-vaginitis may be associated with IBR-IPV virus. Serums prepared from cattle having the genital form of the disease did not always have detectable antibody titers.

Animals↗
PubMed1978

Transmission of herpes-simplex virus type 1 in a nursery for the newborn. Identification of viral isolates by D.N.A. "fingerprinting".

The occurrence of herpes-simplex-virus type-1 infections in two newborn infants in a nursery within a one-month period suggested the possibility of transmission in the nursery. One infant may have been infected by his father, who had active herpes labialis at the time of the child's birth. The source of the second infant's infection was not apparent. Viruses isolated from the two infants were "fingerprinted" by cleaving the virus-specific D.N.A. with several restriction endonucleases and comparing the electrophoretic patterns. Isolates from the two infants were identical and differed from other isolates from epidemiologically unrelated cases. This observation confirmed the possibility of transmission of herpes-simplex virus type 1 in the nursery, but did not define the mode of transmission. Type-1 infections are serious in neonates: one of the infants died and an oesophageal stricture developed in the other. The "fingerprinting" technique provides a useful epidemiological technique for tracing the transmission of herpes virus infections.

Adult↗
PubMed1975

In vitro cellular responsiveness in multiple sclerosis patients to a viral isolate from multiple sclerosis brain tissue and to other antigens.

The Clausen modification of the leukocyte migration test was used to test patients with multiple sclerosis, normal subjects, and patients with other neurologic diseases for cell-mediated immunity to 6/94 virus (a parainfluenza virus previously isolated from the brain tissue of a multiple sclerosis patient), c-RNA virus isolated from a tumor, and the nonviral antigens Candida and purified protein derivative. Leukocytes of multiple sclerosis patient showed significantly less mean inhibition of migration by the 6/94 virus (but not by the c-RNA virus, purified protein derivative, and Candida) than did the cells of normal controls and patients with other neurologic diseases. The relationship of these findings to previous observations in this area and to the pathogenesis of multiple sclerosis is discussed.

Antigens, Viral↗
PubMed1976

Isolation of viral specific RNA from SV40 infected cells by viral DNA chemically linked to a cellulose matrix.

SV40 DNA fragments chemically attached to neutral cellulose powder with a water-soluble carbodiimide have been used to isolate late lytic viral specific RNA from virus infected cells. Exhaustive hybridization to SV40 DNA reveals that virtually all of the isolated RNA molecules contain SV40 specific sequences. Comparison with SV40 cRNA prepared with purified Escherichia coli RNA polymerase and a SV40 DNA I template suggests that the purity of the isolated SV40 specific RNA is very close to 100%. The background level for the nonspecific binding of RNA to a purified cellulose matrix is very low. Retention of nonspecific RNA by SV40 DNA-cellulose is only 1.5% of the viral specific RNA isolated under saturating conditions for the column. Sedimentation in neutral sucrose suggests that the major 16S viral specific RNA has been isolated largely intact.

Cell Line↗
PubMedDate not supplied

Morphologic alterations of experimental rubella syndrome in rabbits.

Rabbits were used as experimental subjects for study of circulation of the rubella virus in intrauterine life and of the histopathological alterations produced by inoculation of wild strains during the first third of pregnancy. Fetuses taken in the 14th, 21st and 28th days of pregnancy, as well as 1-month-old and 5-month-old animals were used for the embryologic and virological studied. Of the 20 animals infected, 90% presented histopathological lesions. The most affected viscera being the liver (80%), heart (60%). kidney (30%) and the crystalline lens (5%). Virological study was made of only 11 animals, from which 100% viral isolation was obtained, with similar results between viral isolation and the appearance of lesions in the liver (72%) and the kidney (44%), while a marked discrepancy in the virus-lesion relationship was found for the heart (33%) and the crystalline lens (77%). We conclude that the etiopathogeny of the syndrome cannot be explained only by direct action of the virus on the fetal tissues, but must be multiple.

Animals↗
PubMed1978

Isolation of viral double-stranded RNAs using a LiCl fractionation procedure.

A general procedure for the isolation of virus-specific double-stranded RNA (ds-RNA) is discribed. The procedure is based on the differential solubility of different types of nucleic acids in LiCl. Principal advantages over conventional methods are simplicity, avoidance of enzymatic treatment, and relatively good yields of undegraded ds-RNA while permitting separation of several main groups of cellular and viral nucleic acids from the same batch of tissue. The method has been successfully applied in tissues infected by several representative plant RNA viruses. The virus-specific ds-RNAs obtained have been identified by their resistance to ribonuclease and comparison of their electrophoretic mobilities with those of the corresponding single-stranded RNA (ss-RNA) in polyacrylamide gels. The molecular weights of the ds-RNAs of tobacco mosaic virus, turnip yellow mosaic virus, alfalfa mosaic virus, and peanut stunt virus fit the curved log molecular weight-migration relationship constructed from a set of known marker ds-RNAs.

Chlorides↗
PubMedDate not supplied

Serologic comparison of hepatitis A antigen to echovirus 25 isolate CR69(076) recovered from a patient with viral hepatitis.

A serologic comparison was performed by immune electron microscopy between hepatitis A antigen (related to the MS-1 strain of hepatitis A virus) and a viral isolate, CR69(076), from the stool of a patient in Costa Rica with viral hepatitis. CR69(076) was not antigenically related to hepatitis A antigen but was related to echovirus 25. Thus, it is unrelated to the MS-1 strain of hepatitis A virus.

Antigen-Antibody Reactions↗
PubMed1978

Comparison of WI-38, MRC-5, and IMR-90 cell strains for isolation of viruses from clinical specimens.

With the diminishing supply of the human fetal lung WI-38 cell strain, a replacement for viral isolation is needed. Two candidates are the human fetal lung strains MRC-5 and IMR-90. A comparison of WI-38, MRC-5, and IMR-90 was performed to evaluate efficiency and speed of viral isolation, clarity of cytophatic effect, and ease of growing the cells. The inocula were clinical specimens rather than tissue culture-adapted isolates. Frozen samples of 46 specimens that had previously yielded an isolate on WI-38 were thawed and inoculated onto WI-38, MRC-5, and IMR-90 cells. In addition, 95 freshly taken clinical specimens uf undetermined infectivity were inoculated onto the cell strains. Viral recovery rates were similar on all three strains, as were the appearance and speed of onset of the cytophatic effect. MRC-5 and WI-38 cells remained healthy until generation 36, whereas IMR-90 cells went into crisis by generation 20. The longer life span of the MRC-5 cells makes them more suitable than IMR-90 cells to replace the WI-38 strain for routine use in viral diagnosis.

Cell Line↗
PubMed1978

Simian virus 40 DNA replication in isolated replicating viral chromosomes.

Three subnuclear systems capable of continuing many aspects of simian virus 40 (SV40) DNA replication were characterized in an effort to define the minimum requirements for "normal" DNA replication in vitro. Nuclear extracts, prepared by incubating nuclei isolated from SV40-infected CV-1 cells in a hypotonic buffer to release both SV40 replicating and mature chromosomes, were either centrifuged to separate the total SV40 nucleoprotein complexes from the soluble nucleosol or fractionated on sucrose gradients to provide purified SV40 replicating chromosomes. With nuclear extracts, CV-1 cell cytosol stimulated total DNA synthesis, elongation of nascent DNA chains, maturation and joining of "Okazaki pieces," and the conversion of replicating viral DNA into covalently closed, superhelical DNA. Nucleoprotein complexes responded similarly, but frequently the response was reduced by 10 to 30%. In contrast, isolated replicating chromosomes in the presence of cytosol appeared only to complete and join Okazaki pieces already present on the template; without cytosol, Okazaki pieces incorporated alpha-(32)P-labeled deoxynucleoside triphosphates but failed to join. Consequently, replicating chromosomes failed to extensively continue nascent DNA chain growth, and the conversion of viral replicating DNA into mature DNA was seven to eight times less than that observed in nuclear extracts. Addition of neither cytosol nor nucleosol corrected this problem. In the presence of cytosol, nonspecific endonuclease activity was not a problem in any of the three in vitro systems. Extensive purification of replicating chromosomes was limited by three as yet irreversible phenomena. First, replicating chromosomes isolated in a low-ionic-strength medium had a limited capability to continue DNA synthesis. Second, diluting either nuclear extracts or replicating chromosomes before incubation in vitro stimulated total DNA synthesis but was accompanied by the simultaneous appearance of small-molecular-weight nascent DNA not associated with intact viral DNA templates and a decrease in the synthesis of covalently closed viral DNA. Although this second phenomenon appeared similar to the first, template concentration alone could not account for the failure of purified replicating chromosomes to yield covalently closed DNA. Finally, preparation of nucleoprotein complexes in increasing concentrations of NaCl progressively decreased their ability to continue DNA replication. Exposure to 0.3 M NaCl removed one or more factors required for DNA synthesis which could be replaced by addition of cytosol. However, higher NaCl concentrations yielded nucleoprotein complexes that had relatively no endogenous DNA synthesis activity and that no longer responded to cytosol. These data demonstrate that continuation of endogenous DNA replication in vitro requires both the soluble cytosol fraction and a complex nucleoprotein template whose ability to continue DNA synthesis depends on its concentration and ionic environment during its preparation.

Cell Line↗
PubMed1977

Characteristic early electroencephalographic changes in herpes simplex encephalitis.

We review electroencephalograms taken from 17 patients with severe meningoencephalitis within seven days of onset of CNS symptoms and prior to cortical brain biopsies. All patients had CNS disease clinically compatible with the diagnosis of herpes simplex encephalitis (HSE). The diagnosis was demonstrated by the isolation of virus from the brain in five patients (group 1) but considered highly unlikely in the other 12 patients (group 2) by negative immunofluorescent studies and failure of viral isolation from the brain tissue. Abnormal but nonspecific EEGs with diffuse or focal slowing were found in all patients. Distinctive high-voltage, 1-cycle-per-2-to-3 seconds periodic sharp waves from unilateral temporal lobes were seen only in three of the five patients with virologically proved HSE but in none of the 12 patients without viral isolation. This EEG pattern is strikingly similar in all three patients, regardless of their age, and may be specific for the early diagnosis of HSE prior to brain biopsy. The EEGs of the other two patients with proved HSE did not contain such abnormalities. Athough periodic EEGs with some resemblance to those previously described may occur in other CNS disorders, their presence strongly suggests the diagnosis of HSE when recorded from patients with viral meningoencephalitis. Moreover, EEGs may help locate the best site for cerebral biopsy since maximal yield of the virus in this study was from unilateral temperoal lobes corresponding with the site of local EEG changes.

Adolescent↗