PubMed Health⌕ Search

Biomedical subjects

A M Serebrianyĭ

Publications and source records attributed to A M Serebrianyĭ.

At least 19 recordsLinked to original sources
PubMed2006

[Use of a cytogenetic method for buccal epithelium study, and a method of laser correlation spectrometry for health disturbances monitoring in children].

Buccal epithelium cytogenetic disturbances were studied in schoolchildren from Moscow schools, a country school (Novgorod region) and a Moscow boarding school for chindren with musculoskeletal diseases (scoliosis and kyphosis). The minimal mean frequency of cells with karyorrhexis were revealed in children from an ecologically pure Novgorod region. Moscow schoolchildren demonstrated more than 13-fold higher level of this parameter. Children with spinal deformities had an intermediate frequency. Cells with karyolysis minimal mean frequency were observed in Moscow pupils. Children from Novgorod demonstrated a statistically valid higher level of this parameter, and the maximum was reached in Moscow boarding school. No difference between these groups was revealed in a study of the mean frequency of binucleated cells, cells with pyknosis, cells with micronuclei, or "broken eggs" incidence. Laser correlation spectrometry (LCS) method was used for parallel studies. It was shown that the distribution of spectra in Moscow pupils and in children with spinal deformities differs from that in children living in ecologically pure region. Normal spectra prevailed in pupils of country school, who demonstrated, in addition, high levels of anabolic and low levels of catabolic type metabolism. The examined Moscow schoolchildren demonstrated almost the same incidence of normal spectra. They differed from the country children by statistically valid reduction of anabolic type spectra, and by increased levels of catabolic type spectra. Young patients with spinal deformities demonstrated the maximum incidence of catabolic type spectra. The authors suggest the availability of a qualitative correlation between both the monitoring methods used in this study. It was shown that children living in unfavorable conditions and patients with musculoskeletal diseases manifested an enhanced incidence of buccal epithelium cells with karyorrhexis and karyolysis, as well as higher levels of catabolic type spectra accompanied by reduction of normal and anabolic type spectra.

Cell Nucleus↗
PubMed2005

[On antimutagenesis mechanism in plants].

The effect of nitrosylmethylurea (NMU) on the mitotic index and the frequency of cells with aberrations, as well as the effects of pre- and posttreatment with antioxidant ambiol on the NMU effects were studied on seedlings of common winter wheat Triticum aestivum, cultivar Moskovskaya 39. Both pre- and posttreatment with ambiol resulted in antimutagenic effect but after posttreatment, the effect was lower. Irrespective of type of seedling treatment with ambiol and the time of their fixation (45, 48, and 51 h), when mitotic index is plotted versus frequency of cells with aberrations, all experimental points fall on the same regression line with coefficient of correlation of -0.82 (P < 0.001). This implies that the same mechanism underlies antimutagenic effect irrespective of when the antimutagen was applied, before or after the knockout mutagen dose. This also suggests that the antimutagenic effect is independent of the degree of the mutagen-induced damage, because by the time of posttreatment, the volume of genome damage is already determined and the antimutagen fails to change it. Finally, this suggests that irrespective of time of antimutagen treatment, the mutation frequency is reduced by the mechanism of stimulated repopulation.

Antimutagenic Agents↗
PubMed2003

[The cell composition in the lymphocyte population and the radiation adaptive response].

Using lymphocytes of 5 healthy individuals the ability to adaptive response (AR), cell composition of population after PHA stimulation, changes in cell composition population after irradiation in the dose of 1.0 Gy and after irradiation in adaptive (0.05 Gy) and challenge (1.0 Gy) doses have been studied. AR observed in 2 of the 5 individuals only. After PHA stimulation the persons with AR have the total amount of cells after mitosis or during mitosis (the number of binucleated cells + the number of multinucleated cells + the whole cells with micronuclei + the number of mitotic cells) on average is higher than in persons without AR. In individuals with AR the linear correlation between the number of binucleated cells with micronuclei (on the 1000 scored binucleated cells) and the part of binucleated cells in the population is observed with coefficients of correlation -0.89 and -0.91. In the humans without AR this correlation is absent. The correlation observed permits to suppose that AR may occur at the expense of not only the decrease in number of damaged lymphocytes, but also the increase in the share of not damaged binucleated cell with the stable number of damaged cells.

Adaptation, Physiological↗
PubMed2002

[Stimulated repopulation as a basis of antimutagenesis and the adaptive response in plants].

Wheat seeds were used to study (1) modification of the radiation adaptive response (AR) with antioxidant anphen and (2) modification of the clustogenic effect of N-methyl-N-nitrosourea (MNU) with various agents. Pretreatment with anphen enhanced AR. Each pretreatment (irradiation with 0.25 Gy, treatment with anphen, treatment with anphen followed by irradiation with 0.25 Gy) decreased aberration frequency. This parameter proved to be in a linear dependence with mitotic index (MI) with correlation coefficient -0.978; the regression line passed through the point corresponding to spontaneous MI and spontaneous aberration frequency. Upon treatment with MNU, the antimutagenic effect was observed for various pretreatments (a low concentration of MNU, antioxidant phenoxan, irradiation with 0.25 Gy). Again, MI and aberration frequency were in inverse proportion with correlation coefficient -0.99, and the regression line passed through the point with spontaneous MI and spontaneous aberration frequency. The same dependence was observed for previously published data on modification of radiation AR with phenoxan. The results were hard to explain in terms of the repair-associated mechanism of AR and the antimutagenic effect. Hence, a nonspecific inducible process of stimulated repopulation was assumed to be a common mechanism of AR and the antimutagenic effect in plants.

Adaptation, Physiological↗
PubMed1998

[Properties of progeny of irradiated cells].

On cells in culture (HeLa, Chinese hamster cells) examined after gamma-irradiation with different doses, properties of the progeny of cells that survived for more than 30 generations have been studied. In the progeny of irradiated cells, the induction of lethal (micronuclei-MN) and nonlethal (sister chromatid exchanges--SCEs) cytogenetic alterations, radiosensitivity, adaptive response induction, and the influence of repair of potentially lethal damages (PLD) on the appearance of MN were detected. The cytogenetic damages are considered as manifestation of genomic instability. In descendants of the irradiated cells the increase in SCE induction and the formation of cells with high SCE level were observed; besides, an enhanced frequency of cells with MN were noticed. Then in the progeny of irradiated cells the radiosensitivity was increased and no adaptive response was induced. It has been found that the PLD recovery led to a decrease in the degree of manifestation of lethal damages (MN) in the progeny of irradiated cells. It was stated that PLD repair could eliminate the damages that result in genomic instability. These effects were registered during more than 20 generations after irradiation. The degree of alterations in the progeny of irradiated cells depends on the dose of irradiation, but the alterations are seen induced when cells are irradiated by low does (0.5 Gy). We can conclude that the low level of DNA damages can induce genomic instability. Forms of genomic instability in the progeny of irradiated cells and possible ways of its induction are discussed.

Adaptation, Physiological↗
PubMed1996

[A comparison of the patterns of delayed cell death after exposure to genotoxic agents].

A lot of data have been provided on different types of cells showing that ionizing radiation induces a hereditable genome instability, which may lead to mutations chromosome aberrations and cell death. In this paper we studied delayed death, proliferative activity, sensitivity to genotoxic agents to progeny of HeLa and LL cells following treatment with ionizing radiation, cis-platinum, methylhydroxurea which induce different types of lesions with different rate of repair. The rate of death of the progeny, dynamics of the clonogen ability recovery, growth rate recovery after the treatment with genotoxic agents are different. We have supposed that the delayed cell death may be associated with different types of hereditable lesions.

Animals↗
PubMed1988

[Specificity of mutagenic effect of N-nitroso-N-methylurea and relation between its mutagenic activity and carbamoylating properties].

Significance of carbamoylation for mutagenic effects of N-nitroso-N-methyl-urea (NMU) on the CHO-AT3-2 cell line of Chinese hamster was studied. True point mutations occurred, due to alkylation. Carbamoylation combined with alkylation, or carbamoylation after alkylation induced the increase in other types of gene mutations as well as micro- and macroaberrations. These effects may be explained by the synergistic effect of alkylation and carbamoylation. Possible mechanisms and levels of interaction between alkylation and carbamoylation are discussed.

Animals↗
PubMed1987

[The structure of products of modification of nucleotides and DNA by ethyleneimine and thio-TEPA].

Previously undescribed products of dGMP, GMP, AMP, dCMP and TMP aminoethylation by ethylenimine and N,N',N"-triethylenethiophosphoamide (thio-TEPA) have been obtained and shown to be aminoethyl esters of nucleotides with the free or substituted amino group. In case of dGMP and GMP ethylenimine and tio-TEPA alkylate not only phosphate but also the base residue at the N7 position. The 7-aminoethyl derivatives of dGMP and GMP, which thio-TEPA afforded, were characterized whereas the corresponding ethylenimine derivatives are decomposed under alkaline conditions in the course of the isolation. Possible reasons of extreme instability of these compounds are given. For the first time the ability of thio-TEPA to alkylate DNA at position 7 of guanine residue is shown by means of the luninescence method.

Alkylation↗
PubMed1986

[Directions of alkylation of deoxyguanosine and deoxyguanylic acid by thio-TEPA].

As exemplified with the reaction of well-known anticancer agent thio-TEPA with dGMP, the ability of ethylenimine derivatives to modify this DNA component under the conditions approaching the biological ones was demonstrated for the first time. Modification involves mainly the phosphate group alkylation. In addition, thio-TEPA alkylates the base in dGMP at position 7. The formation of dGMP 7-alkyl derivatives was confirmed by detecting the luminescent products generated in the course of this reaction.

Alkylation↗
PubMed1980

[Role of carbamoylation processes in the cytotoxic action of nitrosoalkylureas].

The treatment of an asynchronous LL cell line population, being in the log phase of growth, with isocyanate (one of the nitrosourea degradation products) results in the cell death of about 50% of the whole population. The other part of this cell population is unsensitive to this chemical, even at concentrations 100 times more than those equal the LD50 doses. The cell death is due neither to inhibition of DNA-synthesis nor to DNA (single or double strand) breaks or DNA-membrane complex degradation. It is assumed that a mechanism highly sensitive to carbomoylation may be operating in some period of the cell cycle.

Alkylation↗
PubMed1976

[Structural derangements in deoxyribonucleoprotein complex damaged by N-nitroso-N-methylurea].

The effect of deoxyribonucleoproteid (DNP) solubilization under conditions of the ionic strength of the medium approaching the physiological one depended greatly after the treatment with a mutagen - N-nitroso-N-methylurea (NMU) on the NMU concentration. Apparently, for the change of DNA into a soluble state the critical number of groups in the DNA and protein should be modified. On the basis of the data obtained by circular dichroism and viscosimetry a conclusion was drawn that after the NMU treatment the DNP complex became soluble in the solvents with the ionic strength approaching the physiological one, chiefly as the result of labilization and dissociation of DNA-protein bonds.

Chemical Phenomena↗