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Biomedical subjects

A Iu Sungurov

Publications and source records attributed to A Iu Sungurov.

At least 19 recordsLinked to original sources
PubMed1995

[The effect of millimeter-range electromagnetic and of ionizing radiation on the body and thymocytes of mice and rats].

Radiomodifying effects of ultra-high frequency electromagnetic radiation (UHFER) were studied using laboratory mice and rats, as well as irradiated rat thymocytes in vitro. The resistance of mice to lethal effects of X irradiation was increased by preceding UHF treatment at 7.1 mm wavelength. By means of electron paramagnetic spin resonance, it was revealed that UHFER induced a sufficient decrease in free radicals and iron-binding proteins in rat thymus following UHF irradiation in vivo. The UHFER of rat thymocytes caused similar changes in Acridine orange binding to cellular DNA, light scatter parameters of thymocytes, their own UV fluorescence and partition in two phase systems as X irradiation. Possible mechanisms of these effects are discussed.

Animals↗
PubMed1994

[Lymphocyte mechanoluminescence].

A unique installation and an original investigation method are described for studying mechanoluminescence of lymphocytes. The spectral content of mechanoluminescence of lymphocytes of human peripheral blood showed maxima of optical emission at 262, 291, 335 and 412 nm. Intraperitoneal administration of hydrocortisone in mice enhances thymocyte mechanoluminescence intensity after 2 and 3 days by 33 and 62%, resp. It is shown that Acridine orange, reacting with murine thymocytes and their nucleoids, affects intensity of their mechanoluminescence, depending on the value of concentration of the injected intercalator.

Acridine Orange↗
PubMed1987

[Early changes in the state of the cell surface and nucleoid of irradiated Ehrlich ascites carcinoma cells].

For cells of Ehrlich ascite carcinoma, irradiated by the dose of 10 Gy, a decrease in the coefficient of cell distribution in the two-phase polymer system--dextrane-polyethylene-glycol and an increase in the nucleoid viscosity are shown. The values of both indices characterizing the state of the cell surface and nuclear DNA by the same way have changed in time after irradiation: the maximum effect was observed 1 hour after irradiation and the normalization of the both indices was marked 5-6 hours after it.

Animals↗
PubMed1987

[Comparative study, using fluorescent methods, of cell membranes and their reconstituted liposomes].

Cell plasma membranes and proteoliposomes reconstituted from solubilized plasma membranes of thymocytes and Ehrlich ascites carcinoma cells have been studied by fluorescent methods. It has been shown that proteoliposomes are characterized by greater polarization and rigidity of microsurroundings in membrane proteins and greater microviscosity of membrane lipids. Proteoliposomes from thymocyte membranes contain less membrane proteins and express lower polarity of the lipid bilayer than proteoliposomes from Ehrlich ascites cells.

Animals↗
PubMed1986

[Changes in thymocyte size over time].

The dynamics of cell sizes was studied for rat thymus lymphocytes under a short-term culture in the Ringer-Krebs medium and in medium 199 with 10% serum, as well as under in vivo conditions. It has been shown that under incubation in the nourishing medium and in vivo, there are rhythmical changes in the shape of cell distribution according to sizes. Ionizing irradiation of cells causes an increase in the portion of small cellular forms, this process also being of phase character.

Animals↗
PubMed1986

[Surface changes in irradiated thymocytes studied by partition in 2-phase systems and electrophoresis].

A study was made of thymocyte surface changes 1-6 hour after the irradiation in a dose of 4 Gy by means of two phase partition in dextran-polyethylenglycole systems and of electrophoretic mobility registration. A decrease in the two phase partition coefficient (by 20% per cent in one hour after irradiation) was registered. The electrophoretic mobility of irradiated cells did not change.

Animals↗
PubMed1986

[Changes in the ultraviolet fluorescence and the size of Ehrlich ascites carcinoma cells in the 1st hours after X-ray irradiation].

Using the Ehrlich ascite carcinoma cells, a decrease in ultraviolet fluorescence (UVF) was demonstrated one hour following a 10 Gy X-irradiation, and an increase in UVF 5 hours following the same irradiation. The same changes were demonstrated for cell turbidity. Association between the optical changes and those in cell radius and membrane protein state is discussed.

Animals↗
PubMed1984

[Partition of cell suspensions in 2-phase systems].

The physical principles of cell suspension partition in aqueous two-polymer phase systems are considered. The partition procedures and phase composition are analyzed. The results of application of analytic and preparative two-phase partition are presented.

Affinity Labels↗
PubMed1984

[Cell electrophoresis].

The physical principle of cell electrophoresis, the role of media pH and ionic strength, and the nature of cell coat electric charge are considered. The advantages and defects of analytic and preparative cell electrophoresis variants are analyzed. The results of use of cell electrophoresis for studying and separation of erythrocyte, leukocyte and bone marrow cell suspension are presented.

Animals↗
PubMed1983

[Isovelocity separation of cell suspensions].

The physical principles of cell isovelocity sedimentation are considered. The advantages and disadvantages of various methods used for cell velocity sedimentation are analysed. Results of employment of these methods for separation of erythrocytes and bone marrow cell suspensions are presented.

Animals↗
PubMed1982

[Separation of a rat thymocyte population in a ficoll-paque gradient. I. Relation of cell buoyant density to biological parameters].

Rat thymic cells were fractioned in the one-step Ficoll-Paque gradient. The three fractions obtained differed from one another with respect to average cell sizes, protein and DNA contents per cell. The light fraction cells revealed the maximum incorporation of labeled precursors into their nucleic acids, a relatively low hydrocortisone sensitivity and a diminished adhesion capacity. Following preincubation of thymus cell suspension and its gamma-irradiation, the number of the heavy fraction cells increased. The enrichment of the heavy fraction of cells with cortical thymocytes, including terminal ones, is supposed.

Animals↗
PubMed1982

[Separation of a rat thymocyte population in a ficoll-paque gradient. II. Dynamics of the cell count in different media and the effect of thymolytic factors].

Rat thymocytes were fractioned in the Ficoll-Paque gradient. Cells of various fractions were tested for their ability to survive in several nutritional media at 37 degrees C for 5 hours. In serum-less medium 199, the majority of cells died. The addition of bovine serum (10%) to medium 199 resulted in a sharp increase in the number of live cells in the light fractions. Again, the number of live cells in the light fractions was increased upon the 3 hrs-incubation in the serum-less medium containing hydrocortisone, as well as of cells obtained from animals previously injected with hydrocortisone. The X-irradiation of thymocyte suspension led to an obvious augmentation of the number of live cells, belonging to the medium fraction, after a 5 hours' incubation. A possibility is discussed of the increase in cell numbers of different fractions as the result of the "apoptotic" manner of their death.

Animals↗
PubMed1982

[Separation of a rat thymocyte population in a ficoll-paque gradient. III. The optical characteristics of the fractions].

Values of the own ultraviolet fluorescence (UVF) intensity, of the relative UVF intensity (i/R2 proportion, where i--UVF-intensity, R--cell radius), of optical densities of cell suspensions beyond their light absorption band as well as of rates of light scattering by cells at the 90 degrees angle to the beam direction were determined for rat thymocyte fractions obtained by sedimentation of the total thymocyte population on the Ficoll-Paque layer (rho=1.077). It has been shown that the upper (less dense) thymic fractions have the greatest values of parameters assayed when compared with the bottom cells. Interrelations of the data obtained with those on the cell sizes, cytoprotein contents and internal cellular structure are discussed.

Animals↗
PubMed1981

[Various biochemical and biophysical properties of a subpopulation of rat thymocytes isolated in a Ficoll gradient].

Subpopulations of rat thymocytes were obtained by cell precipitation in a single-stage transient phycoll gradient (isorapid precipitation). The fraction obtained were characterized in terms of the size, intensity of UV fluorescence, protein content and nucleoid mobility. The radius of thymocytes and UV fluorescence intensity monotonously increased during the transfer from the upper to lower fractions. The cells of medium-size fractions were characterized by the minimum content of cytoproteins and maximum mobility of nucleoid. In order to evaluate the density of thymocytes in the fractions, use was made of an additional cell precipitation in the phycoll-paque stage rho = 1.077. Incubation of thymocytes in medium 199 with a 10% rat serum led to the increased cell density in all the fractions, particularly in medium-size ones. Gamma-irradiation of thymocytes in a dose of 5 Gy appreciably accelerated the process under consideration. It is assumed that the medium-size fractions are enriched with thymocytes in G1 S phase, while lower fractions in G2 phase of the mitotic cycle. At the same time the fractions obtained appear to contain the subpopulations of thymocytes undergoing different stages of differentiation.

Animals↗