PubMed Health⌕ Search

Biomedical subjects

A I Kolosov

Publications and source records attributed to A I Kolosov.

11 recordsLinked to original sources
PubMed1979

N-acetyltransferase activity as a possible criterion in prognosing the anti-tumor effect of cyclophosphamide.

The results obtained in the present study indicated that a reduction in the activity of N-acetyltransferase (EC 2.3.1.5) occurs in cyclophosphamide-treated mice with sarcoma 37. A difference in variations of the level of N-acetyltransferase activity in outbred mice with and without tumors was observed in cyclophosphamide-treated animals. It was established that the effect of cyclophosphamide on the activity of N-acetyltransferase depends on the initial level of the enzyme activity (phenotype of acetylation) as well as on the genotype which determines the N-acetyltransferase activity.

Acetyltransferases↗
PubMed1978

[Phenotypic changes in acetylation in tumor patients].

The authors have determined the activity of N-acetyltransferase and the type of acetylation in patients with cancer of the lung (38) and gastrointestinal tract (39), and in 72 control individuals. It was found that there is a changed distribution of patients in relation to the activity of acetylation in maintaining the normal correlation of "slow" and "fast" acetylators. There was noted an increase in N-acetyltransferase activity with greater spread of the tumor process, whereas the activity decreased in radical operations and increased in palliative surgical procedures and in the presence of recurrences or metastases.

Acetylation↗
PubMed1977

[Activity of coenzyme A and N-acetyltransferase during tumor growth].

The activity of acetylation of sulphadimezine in C57B1/He mice with the low spontaneous tumour incidence was significantly lower than in the C3H/Sn mice with high spontaneous tumour incidence. The development of malignant melanoma B-16 in the C57B1/He mice led to increase in the activity of the sulphadimezine acetylation. Along with the previously obtained information, these data indicated the relationship between the development of tumour process and changes in the activity of the enzyme N-acetyltransferase. No difference in the acetylation of the sulphaylamide was found in the same groups of mice; this points to the absence of any differences in the coenzyme A level.

Acetyltransferases↗
PubMed1976

On the relationship between the activity of acetylation, growth of experimental tumors and efficacy of their suppression by hydrazine sulphate.

The growth of experimental tumors was found to involve an intensification of acetylation of sulphadimidine. Inhibition of carcinosarcoma Walker-256 by 88% and sarcoma-180 by 36% on treatment with 60 mg/kg body weight of hydrazine sulphate was followed by decreases in the rate of acetylation of 39.4 and 29.4%, respectively. When treatment failed to suppress tumor growth (sarcoma-45), acetylation level showed no decrease. The results point to a correlation between growth of tumors and their inhibition on the one hand and the level of acetylation on the other.

Acetylation↗
PubMed1976

Effects of some polynucleotides on DNA synthesis in human lymphocytes.

The effect of several single-and double-stranded synthetic polyribonucleotides on the 3H-thymidine incorporation in intact and PHA-stimulated human lymphocyte cultures was investigated. Only polyuridilic and polyguanilic acids were found to stimulate DNA synthesis in the intact cells. All other polynucleotides tested had much weaker or had no stimulating activity. PHA-activated lymphocytes responded to addition of polynucleotides by the decrease of 3H-thymidine uptake. The mostly profound inhibition of lymphocyte response to PHA was observed with polyguanilic acid.

Adjuvants, Immunologic↗
PubMedDate not supplied

[Antiviral activity of several nucleic acid components methylated in the N-position].

The degree of reproducation of Rous sarcoma, mumps, and vaccinia viruses in chick embryo cell culture incubated in the presence of 9-methyladenine was considerably lower than reproducation of these viruses in the cells propagated without this substance. 1-methyluracil and 1-methylthymine reduced considerably the amount of Rous sarcoma virus produced by the cells as compared to the controls. The presence of these substances in the maintenance medium does not prevent virus infection of the cells, and their effect appears to be associated with nonspecific action on the late stages of the virus reproduction.

Adenine↗
PubMedDate not supplied

[Effect of synthetic polyribonucleotides on the immunological and colony-forming activity of irradiated bone marrow cells].

The experimental data are presented concerning the effect of polyribonucleotides on the immunologic and colony forming ability of bone marrow or irradiated mice. All the compounds under study exhibited a pronounced, but to a different degree, colony-forming and immunostimulating action. The comparative study of the influence of polyribonucleotides on the number of endogenous colonies and antibody-forming cells showed an inverse relationship between these parameters: The preparations exerting the most pronounced immunostimulating effect had an insignificant colony-forming action and vice versa. This is evidently indicative of the capacity of these preparations to turn the differentiation of haemopoietic stem cells towards the immunopoiesis.

Animals↗