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Biomedical subjects

H Cerná

Publications and source records attributed to H Cerná.

At least 37 records · Page 2Linked to original sources
PubMed1987

Sexual aggressivity and androgens.

Male sex hormones are ascribed a great importance in the literature from the point of view of sexual activity and aggressive behaviour. Two cases of sexually motivated murder are described, committed by delinquents with low levels of testosterone in plasma: one a patient with Klinefelter's syndrome; the other a man after castration. Even a decreased level of androgens, either primary or secondary, is not an absolute prevention of sexually aggressive behaviour.

Adult↗
PubMed1987

Two-dimensional gel electrophoresis of myc gene products after cleavage by viral protease p15.

An analysis of myc-specific protein (p58myc), precipitated from cells transformed by virus OK10, by means of two-dimensional gel electrophoresis revealed the presence of two variants of p58myc differing in their isoelectric point. Both variants are completely cleaved by protease p15 as is the c-myc gene product precipitated from 16Q cells. The cleavage fragments of c-myc and v-myc protein do not differ in size but differ in their stability.

Animals↗
PubMed1985

Evidence for p15 cleavage site in myc-specific proteins of avian MC29 and OK10 viruses.

Myc-related proteins were precipitated from MC29 virus-transformed cells (PR-2) and from OK10 virus-transformed cells (9C) by anti-gag and anti-myc sera. Immunoprecipitates were cleaved with the avian retroviral protease p15 and the cleavage products analyzed in SDS-PAGE. Cleavage fragments of p110gag-myc (product of MC29 virus) and p58myc (product of OK10 virus) showed the presence of a p15 cleavage site within the myc-specific region. The site is missing in deletion mutants of MC29 virus.

Animals↗
PubMed1985

Comparison of avian MC29 and MC31 viral onc proteins.

Lysates of [35S]methionine-labelled quail cells transformed by MC31 virus were immunoprecipitated with anti-myc or anti-gag serum and analysed in SDS-PAGE. A protein with a molecular weight 110K was found in both immunoprecipitates. Thus, the product of the MC31 genome is a gag-myc fusion protein with the molecular weight as the product of the MC29 genome. Comparison by tryptic peptide mapping and p15 cleavage analysis showed no differences between both P110 proteins.

Animals↗
PubMed1984

Analysis of gag-myc proteins of partially transformation-defective mutants of avian myelocytomatosis virus strain MC29 by in vitro cleavage with protease p15: indication for the presence of specific cleavage site p15 in the myc domain of fusion protein.

Gag-related proteins were immunoprecipitated from [35S]methionine-labelled cells of the PR-2 line which contained p110 protein as well as from quail cells transformed by deletion mutants 10A, 10C, and 10H of MC29 virus. Immunoprecipitates were incubated with oncoviral protease p15 and cleavage products were analyzed in SDS-PAGE. The major 56K fragment (F56) of p110 was further analyzed by tryptic peptide mapping. The results showed that except for the myc domain of p110, a portion of p27 is also present in F56. Cleavage of 100K, 95K, and 90K proteins coded by three MC29 deletion mutants resulted in major fragments 66K, 60K, and 56K, respectively. The existence of further cleavage fragments and presence of the p15 specific cleavage site in the myc domain of MC29 specific proteins is discussed.

Animals↗
PubMed1982

In vitro cleavage of gag-myc fused protein P110 of a defective leukaemia virus MC29 by retroviral protease p15.

Gag-related proteins were precipitated from 35S-methionine-labelled cells of the PR-2 line derived from a hepatoma induced by virus MC29. Immunoprecipitates were incubated with viral protease p15 and the cleavage products of P110 were analysed in SDS-PAGE. The major cleavage fragment of P110 is a protein with mol. wt. of 56 000. Preparative isolation of the non-gag fragments from protein P110 by means of a gag immunosorbent showed that the 56K fragment did not contain any gag specific antigenic determinants. This finding was also confirmed by performing immunization with this fragment. Cleavage of protein P110 and the properties of cleavage products are discussed.

Animals↗
PubMed1980

Characterization of tumors induced in adult Macaca mulata monkeys with Carr-Zilber strain of Rous sarcoma virus.

The Carr-Zilber strain of Rous sarcoma virus is highly oncogenic for adult monkeys of the species Macaca mulata. In the present study, we examined some characteristics of tumor growth when the tumor either regressed or progressed until it killed its host. We followed the kinetics of antibody formation to antigens coded by CZ-RSV in animals with a different course of tumor disease. The sera of animals tested contained virus-neutralizing antibodies, in addition to gs antibodies. The results are discussed with regard to the possible virus-productive type of interaction between RSV and the monkey cell.

Animals↗
PubMed1980

Presence of antibodies to the viral proteins in sera of mammals bearing RSV-induced tumours.

The sera of RSV tumour-bearing rats, hamsters and monkeys were tested for the presence of antibodies to RSV proteins. Complement fixation test and radioimmunoprecipitation followed by SDS-polyacrylamide gel electrophoresis were used for detection of antibodies to the products of the gag, env and src genes of RSV. Antibodies to the env and gag gene products were found in sera of tumour-bearing monkeys. Hamster sera contained antibodies to the gag gene products only. No antibodies were detected in sera of tumour-bearing rats. The differences in immunogenicity of RSV gene products in various hosts are discussed.

Animals↗
PubMed1978

Study of group-specific proteins in mammalian cells transformed by Rous sarcoma virus.

Lysates of various mammalian RSV-transformed cells labelled with 35S-methionine were tested for the presence of gs proteins and for the size of these molecules by means of antisera, using sodium dodecyl sulphate--polyacrylamide slab gel electrophoresis. In no case was the presence of gs proteins detected in the analyzed immunoprecipitates; only in RSH-mix cells a quantitative difference in the contrast of a 70 000-molecular weight protein was found. The autoradiograms of simultaneously tested immunoprecipitates of lysates of RSV-transformed chicken cells clearly showed the presence of p27 and after a short-term labelling also of the gs precursor molecule (pr76). The cause of the failure in detecting gs proteins by the used method in two mammalian RSV-transformed lines, in which the gs antigens were previously detected by complement fixation test, are discussed.

Avian Sarcoma Viruses↗
PubMed1978

Fractionation of proteins from Rous sarcoma virus and avian myeloblastosis virus by isoelectric focusing.

The isoelectric focusing technique in the pH gradients was used for a preparative isolation of proteins from Rous sarcoma virus and avian myeloblastosis virus. The purified major gs protein, p27 (pI = 9.1) and the gP86 (pI = 5.3) were obtained after disruption of virus with 1% non-ionogenic detergent in the presence of 6M urea. The p10, p15, and p19 were present in the same range of pH (pI = 6.8). A strongly basic protein, immunologically active, presumably the p12, was found in the alkaline region of the pH gradient 10.8. These proteins fully retained their immunological activity. On the other hand, in the acidic region of the pH gradient between pH 4 and 5, strong precipitates were regularly found. These precipitates were complexes which were formed by interaction of the acid components of ampholines with the viral proteins during isoelectric focusing. Almost all viral proteins were present, differing only in quantity. The complexes were stabile in 1% non-inogenic detergent and 6M urea. They were dissociated with 1% SDS and 5M urea, and had no immunological activity. The methods of virus disruption and possibilities of formation of the ampholine-viral protein complexes are discussed.

Avian Leukosis Virus↗
PubMed1977

Biosynthesis of subviral oncogenic particles (virosomes) in mitochondria of Rous sarcoma and Rauscher murine leukemia cells.

Experimental evidence for the presence and biosynthesis of subviral, leukemogenic particles in the isolated mitochondria of spleen cells of mice infected with Rauscher murine leukemia (RML) virus is presented. These subviral particles sediment at a density of 1.27-1.29 g/ml and induce splenomegaly and RML three weeks after i.v. or i.p. administration to white mice. Virosomes have been labelled with [32P]phosphate in the isolated mitochondria from RML spleen cells and high molecular weight (70S) [32P]RNA has been isolated from these subviral, leukemogenic particles. Rauscher virus group specific antigens were detected by immunodiffusion in the inner membrane and matrix fraction of the mitochondria of RML spleen cells. These results together with our earlier findings strongly suggest that mitochondria of the transformed cells participate in the biosynthesis of RNA tumor viruses. Possible mechanism of the penetration of viral genetic information of RNA tumor viruses into mitochondria of tumor cells in vivo is discussed.

Animals↗