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R S Dreizin

Publications and source records attributed to R S Dreizin.

At least 19 recordsLinked to original sources
PubMed1983

Analysis of sequences of simian adenovirus SA7 (C8) DNA in transformed rat cells and hamster tumour cells.

Different methods of molecular hybridization were used to study DNA sequences of the highly oncogenic simian adenovirus SA7 (C8) present in the genomes of two transformed rat cell lines and in cells from three hamster tumours induced by adenovirus SA7. The entire DNA or the left-hand terminal SalI C fragment (19.5% of the genome) were employed. All cell lines retained an intact left-hand region of the SA7 genome (0 to 12.4 map units). The blot hybridization technique failed to detect any site specificity of integration of SA7 DNA into the cell genome. In all cell lines the expression of the Bg/II D fragment (1.8 to 10 map units) of SA7 DNA was observed. As judged by the patterns of integration of virus sequences into the cell genome, the highly oncogenic simian adenovirus SA7 (C8) is similar to the non-oncogenic human adenoviruses of group C, and is different from the highly oncogenic human adenovirus type 12.

Adenoviridae↗
PubMed1981

Integration of foreign genome fragments into cells transformed or cotransformed with fragmented adenoviral DNA.

The integration of DNA of highly oncogenic simian adenovirus type 7 (SA7) and non-oncogenic human adenovirus type 6 (Ad6) into the genome of newborn rat kidney cells transformed by fragmented DNA preparations was studied using reassociation kinetics and spot hybridization. Transforming DNA was fragmented with the specific endonuclease SalI (SA7) and BglII (Ad6). In contrast to the cell transformation by intact viral DNA, transformation by fragmented DNA resulted in integration into the cellular genome of not only the lefthand fragment with the oncogene but also of other regions of the viral genome. Additionally integrated fragments were stable and preserved during numerous passages of cells lines, although they were no expressed, at least in the case of the Ad6-transformed cell line. The integration of the fragments of SA7 DNA was accompanied by loss of 25-50% of the mass of each fragment. Adding the linear form of the pBR322 plasmid to the preparation of transforming Ad6 DNA also contributed to its cointegration into the genome of the transformed cell. This technique of cell cotransformation with any foreign DNAs together with the viral oncogens may be used as an equivalent of an integration vector for eukaryotic cells.

Adenoviridae↗
PubMed1981

The distribution of guanine-cytosine pairs in adenovirus DNAs.

The distribution of guanine-cytosine (GC) pairs in the DNA of the highly oncogenic simian adenovirus type 7 (SA7) and the non-oncogenic human adenovirus type 6 (Ad6) has been studied by thermal denaturation and CsC1 density-gradient centrifugation. The differential of the DNA thermal denaturation curves shows the presence of pronounced peaks which indicates uneven distribution of GC pairs along the DNA chains and the presence of regions with GC content from 30 to 74% in SA7 DNA and from 40 to 68% in Ad6 DNA. The DNA restriction fragments obtained by treatment with EcoRI, BamHI, SalI, BglII and HindIII were subjected to CsC1 density-gradient centrifugation. GC content of the fragments ranged from 45 to 70% for SA7 DNA and from 43 to 61% for Ad6 DNA. The GC content of the extreme left-hand fragments, where the transforming gene(s) is located, was higher than the average for SA7 DNA and lower than the average for Ad6 DNA. The most GC-rich regions were localized in the centre of the genome. The GC content of the right-hand part of both viral genomes was lower than the average.

Adenoviridae↗
PubMed1979

Biophysical properties of virions of human adenovirus of the type 6 and its DNA.

A study has been made of human adenovirus type 6 (Ad 6) which belongs to the C subgroup of the nononcogenic adenoviruses. The buoyant density of the Ad 6 virions in CsCl gradient was 1.3545 +/- 0.0010 g/cm3. The DNA content determined from the buoyant density values and direct phosphorus analysis was 11.2 +/- 0.5 and 11.5 +/- 0.5 per cent, respectively. The S20,w0 and D20,w0 values for the Ad 6 virions were 795 +/- 18S and (3.255 +/- 0.035) X 10-8 cm2/s. The hydrodynamic parameters of the viral particle and its volume as well as the specific partial volume, the content and the molecular weight of the DNA have yielded a molecular weight of the virions of (203.6 +/- 10.0) X 10(6). The sedimentation constant and the intrinsic viscosity of the DNA have been found to be 32.7 +/- 0.7S and 93.5 +/- 5.0 dl/g, respectively. The molecular weight of the DNA found from these results is (23.4 +/- 0.8) X 10(6). The buoyant density of the Ad 6 DNA measured in CsCl and Cs2SO4 density gradients was 1.7128 +/- 0.0010 and 1.427 +/- 0.001 g/cm3, respectively. The GC content found from the buoyant density and the melting temperature (90.5 +/- 0.1 degrees C in 1 SSC and 75.0 +/- 0.1 degrees C in 0.1 SSC) was 52.6 +/- 1.0 per cent, that is, it is considerably lower than the GC content of 56-60 per cent which, according to the "Green's rule", should be typical of the DNAs of all the human adenoviruses of the subgroup C (30).

Adenoviruses, Human↗
PubMed1979

Physicochemical properties and restriction maps of simian adenovirus type 38 DNA.

The sedimentation constant of simian virus type 38 (SV-38) DNA was estimated to be 31.6S. The intrinsic viscosity of DNA was on average 86.5 dl/g and the length of the molecule determined by electron microscopy was 10.6 micrometer. The average mol. wt., as determined by sedimentation and viscometry, was 21.5 x 10(6), which agreed well with the value derived from the length of the molecule (21.4 x 10(6)) and with the value of 21.2 x 10(6) determined by the relative electrophoretic mobility of the DNA fragments produced by restriction endonucleases EcoR1, SalI and BglII. The buoyant density of the DNA in caesium chloride and casesium sulphate was 1.7185 and 1.4295 g/ml respectively. The melting temperature of the DNA in 1 x SSC was 93.5 degrees C. The GC content calculated from p and Tm values was 59.3%. BglII cleaves SV-38 DNA at three sites producing four fragments with mol. wt.: A, 9.3 x 10(6), B, 5.6 x 10(6), C, 3.3 x 10(6); and D, 2.9 x 10(6). After treatment with EcoR1 and SalI, SV-38 DNA is cleaved into five and six fragments respectively, with mol. wt. for EcoR1 fragments: A, 8.2 x 10(6), B, 6.5 x 10(6), C, 4.0 x 10(6), D, 1.27 x 10(6); and E, 1.07 x 10(6), and for SalI fragments: A, 6.5 x 10(6); B, 5.4 x 10(6); C, 4.2 x 10(6), D, 2.8 x 10(6); E, 2.5 x 10(6) and F, 0.25 x 10(6). The sequence of fragments within the SV-38 DNA molecules for BglII was deduced to be BDCA, and for ECOR1--BCEAD.

Adenoviridae↗
PubMed1979

The spread of rhinoviruses in the Soviet Union (USSR) and in Czechoslovakia (CSSR) and the role of their pathology.

Virological, serological and immunofluorescence studies revealed circulation of rhinoviruses of the strains 1A, 1B, 2, 3, 7, 9, 10, 12, 13, 14, 16-23, 27, 29-33, 42, 48, 53, 56, 60 and 69 on the territory of Czechoslovakia and the Soviet Union. According to virological results, type 48 predominated and was followed in frequency of occurrence by types 27, 14 and 16 in the USSR and 30, 1A and 31 in the CSSR. RV infection in adults with ARD diseases was the aetiology in 28.5% of cases. Among the causative agents of acute rhinitis, rhinosinusitis and otitis, rhinovirus infection makes up a large proportion. Interrelation has been found between rhinovirus infection and chronic inflammation of the mucosa of the nose, the accessory sinuses and the ears. Prolonged course of rhinovirus infection and isolation of the virus in the late stages of disease (1-4 months after its onset) support the presumption that rhinoviruses promote chronicity of inflammation. RV was isolated from patients with chronic pneumonia from the lower respiratory passages (bronchial secretion). Rhinoviraemia was found in a child who died of ARD.

Adolescent↗
PubMed1976

Adenoviridae.

The elevation of the genus Adenovirus to a family named Adenoviridae is described. This family at the present stage contains two genera, mammalian adenoviruses--Mastadenovirus--and avian adenoviruses--Aviadenovirus. The two genera are separated primarily on the basis of difference in immunological properties of the virions.

Adenoviridae↗
PubMed1976

A stable antibody-sensitized erythrocyte diagnostic preparation for detection of rhinovirus type 17 and its antibody.

A diagnostic preparation was obtained by sensitization of formalinized sheep erythrocytes with antibody to rhinovirus type 17. This preparation was agglutinated in the presence of relatively high concentrations of type 17 but not other types of rhinovirus. It could also be used for detection of antibody to rhinovirus type 17 in the antigen neutralization test, the antibody levels determined in this way being similar to those found by conventional virus neutralization tests in cell cultures.

Animals↗
PubMed1975

Diagnosis of rhinovirus-infections by virological and immunofluorescent methods.

In January--May, 1971, detection of rhinoviurs infections among ambulatory patients with respiratory diseases in Moscow was carried out in parallel by virological and immunofluorescent methods. Rhinovirus infections were virologically confirmed in 13% out of 238 patients. By the indirect immunofluorescence technique, rhinovirus antigens of serotype 17 were detected in 2.2% out of 220 patients, of type 1B in 4.3% out of 183 patients, of type 48 in 5.6% out of 123 patients and of type 7 in 4.6% out of 86 patients. The use of immunofluorescence supplemented the results of virological examinations and increase the effectiveness of aetiological diagnosis of rhinovirus infections.

Adenoviridae↗
PubMedDate not supplied

[Viremia in respiratory syncytial virus infection].

Viremia was demonstrated to occur in experimental respiratory syncytial (RS) virus infection in suckling cotton rats and in natural infection in children. RS virus was isolated from the whole blood of the animals in 3 out of 6 experiments at 2, 5, 6, 7 and 15 days after inoculation, the maximum infectious titer being more than 10(4) TCPD50/0.1 ml. RS virus was also isolated from the blood of 7 out of 15 examined children presenting the typical clinical picture of RS virus disease during the epidemic season of RS virus infection. In 6 patients RS virus was isolated from one blood specimen at 1, 6 and 7 days after the onset, in one patient from 3 blood specimens at 6, 9 and 22 days after the onset. The demonstrated long-term persistence of virus in the blood suggests the possibility of existence of chronic RS virus infection.

Animals↗
PubMedDate not supplied

[Development of optimal conditions for isolation of rhinoviruses].

When 366 dispensary patients with respiratory diseases were examined in Moscow during the period December 1969--May 1971, 49 strains of rhinoviruses were isolated out of which 21 strains were identified as type 48. Using Eagle's medium with a single set of amino acids and vitamins for isolation rhinoviruses were isolated in 4.7% of cases, empdoying Eagle's medium with a double set of amino acids and vitamins in 16% of cases. Virus isolation experiments were carried out in HeLa-Bristol cell cultures and diploid strain of skin-muscle cells KM-13-70 in the presence of 30 mM MgCl2 and 2% aminopeptide. The isolation rate of rhinoviruses in both the cell cultures was approximately similar. The average duration of time for isolation of rhinoviruses in diploid cells was 13.4 days, in HeLa-Bristol cells 15 days. All rhinovirus strains were isolated within 3 passages. In addition to rhinoviruses, from the same group of patients 25 Coxsackie A-21 strains, 12 adenovirus strains and 2 herpesvirus strains were isolated using Eagle's medium with double set of amino acids and vitamins.

Adenoviridae↗
PubMedDate not supplied

[Preparation of immune serums for the identification of rhinoviruses].

Six schedules of immunization of rabbits, guinea pigs and rats for production of antirhinovirus immune sera were studied. Sera with virus-neutralizing antibody titers of 1:1000 to 1:50,000 were obtained in rabbits immunized into popliteal lymph nodes. The resulting sera had high titers of antibody to cell components and neutralized the cytopathic effect induced by heterologous strains. Sera from which cell components had been absorbed showed strict type-specificity in the neutralization and indirect immunofluorescent tests. A mixture of sera has been shown to be useful for identification of rhinoviruses by the immunofluorescent procedure.

Animals↗