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G V Selivanova

Publications and source records attributed to G V Selivanova.

At least 37 records · Page 2Linked to original sources
PubMed1988

A cytophotometric analysis of the structure of hypothalamic cell populations in the frog, Rana temporaria (L.), with special reference to seasonal changes in chromatin status.

We used cytophotometry after the Feulgen reaction and UV cytophotometry to measure the DNA content of quiescent cells of the hypothalamic preoptic region (HPR) of adult and juvenile frogs (Rana temporaria) that had been caught in their natural habitat in winter, spring and summer. The histone-to-DNA ratio in cell nuclei was cytophotometrically determined using a combined Feulgen, heparine and alcian-blue staining procedure. The vast majority of HPR cells studied had nuclei with a diploid DNA content. However, we observed great variability in the Feulgen-DNA content of the HPR cell population, which was not detected in the diploid standard (hepatocytes). This heterogeneity in the diploid sample of the HPR cell populations was always greater in prespawning frogs and may have been due to differences in the chromatin arrangement in nuclei. About 1% of cells had a DNA content either ranging between diploid and tetraploid levels (H2C cells) or at the tetraploid level (4C and 2C x 2 cells). The proportion of these cells was not affected by the age of the animals or the annual cycle, thus suggesting that there is no age-related increase in the mean DNA content in the frog HPR. The mean DNA contents of H2C and 4C cells were much higher than those in the standard (hepatocytes). This cannot be simply attributed to the presence of different amounts of nuclear proteins, but rather indicates that at least a certain proportion of the highest DNA contents may be due to a real extra-DNA synthesis.

Animals↗
PubMed1988

[Comparative cytophotometric analysis of the nucleic acid content in the cardiomyocytes of normal rats and following experimental infarct].

The cytophotometrical investigation of gallocyanine-chrome alum stained cardiac muscle cells allows to ascertain that a mean content of the nucleic acids calculated for a single nucleus is essentially higher in the left ventricle myocytes in comparison with the left auricle cells of healthy adult rats. These values in 1-, 2- and 3-nuclear cells of the ventricle are, respectively, 21.3, 19.3, and 18.0, and 14.1, 13.7, 13.5 of arbitrary units (a. u.) in the auricle cells. A difference in cytoplasmic RNA contents of the same cells is more significant, these values are 65.7, 116.4, and 158.9 a. u. in ventricle myocytes, and 33.4, 60.8 and 95.2 a. u. in auricle cells. The nucleic acids content in the nuclei and RNA content in the cytoplasm increase with the development of proliferation in myocytes after experimental myocardial infarction. A relative increase in the nucleic acids content in the nuclei of the same cell types reaches 50, 24, and 10% 11 days after infarction and 56, 38, and 45% 31 days after infarction. A relative increase in cytoplasmic RNA of the same cells reaches, respectively, 52, 17, and 25%, and 70, 57, and 53% 11 and 31 days after infarction. These findings evidence on the greatest synthetic activity of the single-nuclear auricle muscle cells in the process of heart restoration after infarction.

Animals↗
PubMed1987

[Cytophotometric analysis of the protein and nucleic acid content of the nucleus and cytoplasm of resting and proliferation-activated hepatocytes in the mouse].

Mouse hepatocytes, quiescent and activated to proliferation after hepatectomy, were investigated using cytophotometry in the ultraviolet region of selective absorbtion of nucleic acids, and then were examined in the visible region of spectrum after cytochemical reaction for total protein. Some features of RNA and protein accumulation were revealed in the nucleus and cytoplasm of activated cells of different ploidy. The activation resulted in the reduction of histone content and in the increase in the nucleus: cytoplasm ratio in cells of all the ploidy classes.

Animals↗
PubMed1987

[Characteristics of the granules formed in nucleated erythrocytes as affected by cardiotrast].

Numerous granules are formed in frog erythrocytes under the influence of cardiotrast (C) (diethanolamine-3,5-diiodo-4-pyridone-1-acetic acid). However, as revealed by cytospectrophotometric investigation and X-ray microanalysis, no C was accumulated in these granules. It is known that C can dissociate into diethanolamine and 3,5-diiodo-4-pyridone-1-acetic acid. It was assumed that under the influence of C granule formation may occur at the expense of an uncharged diethanolamine form penetrating into lysosome-like structures to be accumulated by protonation process. Diethanolamine was found to provoke granule formation in frog erythrocytes. It is impossible to reveal substance in granules because it is colourless and has no ultraviolet absorbtion band. Under the influence of some inhibitors of energy metabolism on granule formation and the granules formed, their inhibitory effect is exerted on the process of granule formation. In granules isolated by differential centrifugation activity of some marker lysosomal enzymes was found which enabled us to attribute these granules to lysosome-like structures.

Animals↗
PubMed1987

[Cytophotometric analysis of the cell population composition of the the preoptic area of the hypothalamus in the common frog].

DNA contents in squashed cells of the adult frog hypothalamic preoptic region (HPR) were measured using the Feulgen and UV cytophotometry techniques. The histone-DNA ratio in the cell nucleus was determined by means of a combined Feulgen-heparin-Alcian blue staining procedure. The nuclei of the vast majority of HPR cells have a diploid DNA content. However, in cells of this group the mean values of DNA amount and the distribution range were always higher than those in hepatocytes used as a diploid standard. Such a heterogeneity in DNA content in the diploid part of HPR cell population could apparently suggest some differences in the nuclear chromatin arrangement to be always higher in spring before the frog spawning, and it seems to be characteristic of this type of cells. About 1 per cent of cells with hyperdiploid surplus of DNA (H2c cells) as well as of tetraploid cells (4c and 2c X 2 cells) is found in HPR in frogs sacrificed both in winter and in summer. The quota of these cells has no reference either to the frog's age or to the annual cycle. The fact that the mean DNA values in H2c and 4c cells are much higher than in the standard cannot be explained by the presence of different amounts of nuclear proteins only. It is suggested that at least some part of the highest DNA values may be due to an actual extra DNA synthesis in a small constantly existing pool of HPR cell population.

Animals↗
PubMed1987

[Cytophotometric and electron microscopic studies of chronic human skin lymphomas. II. Research on lymph node involvement].

Results of electron microscopic and cytophotometric studies of biopsy material from lymph nodes of patients with cutaneous lymphomas with low degree of malignancy are discussed, with special reference to early diagnostic criteria of the disease. Specific characteristics of tumor tissue involve the presence of atypical lymphocytes with marginal condensed chromatin extrusions of nuclear material, deep invaginations of the nuclear membrane, nuclear pockets, excess of the mean DNA content per nucleus above the diploid standard level, more than 5% of nuclei being in the hyperdiploid area. Electron microscopic and cytophotometric methods allowed to diagnose the tumor injury of lymph nodes, when the traditional histological techniques revealed no signs of malignancy.

Biopsy↗
PubMed1984

[Cytophotometric study of the granules formed in frog erythrocytes incubated in solutions of acridine orange, chloroquine and daunorubicin].

Granules arising in the cytoplasm of Rana temporaria erythrocytes incubated in either solution containing acridine orange, chloroquine or antibiotic daunorubicine were studied cytophotometrically. The stuff concentrations in the granules were estimated under various conditions of incubation. The stuff concentrations in the granules appeared to be 1000-fold higher than in the incubation solutions. The average concentration in the granules did not depend on either the initial concentration of the stuff solution or the incubation time. The stuff concentration in the granules decreases with the increase of the granule size. Mechanisms of cation-acid segregation and accumulation by living cell are discussed.

Acridine Orange↗
PubMed1984

[Cytophotometric and electron microscopic study of chronic human skin lymphomas. I. A study of skin manifestations].

Electron microscopic and cytophotometric studies of low-grade malignant cutaneous lymphomas and non-malignant skin diseases revealed substantial differences between these groups of diseases. In the latter case, the DNA content per nucleus is diploid but in the former an atypical distribution of DNA content per nucleus (more than 5% aneuploid and polyploid nuclei) is observed in addition to a significant excess of the mean DNA content per nucleus above the diploid standard level. In lymphomas electron microscopy reveals clusters of atypical lymphoid cells with irregularly shaped nuclei, nuclear pockets, nuclear extrusions, network of cytoplasmic microfilaments. These features never occur with skin diseases. The data obtained can be helpful in the diagnostics of the low-grade malignant cutaneous lymphomas.

Biopsy↗
PubMed1983

[Possible use of DNA cytophotometry and karyometry for the cytological diagnosis of human prostate cancer].

Karyometric and cytophotometric parameters of the prostate epithelium are examined on the pattern of aspiration biopsy under benign hyperplasia and carcinoma of different grades of differentiation. The results obtained suggest that the distribution of the nuclei, according to their volume and DNA values, and the calculated index of DNA accumulation per cell may be used for differential diagnostics of the prostate cancer and for making the morphological type of tumor more precise.

Biopsy, Needle↗
PubMed1983

[Cytophotometric study of the DNA content in the cells of the preoptic area of the hypothalamus in hibernating common frogs].

The DNA content in the squashed Feulgen stained cells of the hypothalamic preoptic region in wintering adult and juvenile frogs was measured cytophotometrically. The vast majority of hypothalamic cells studied showed diploid DNA contents. Only 0.9% of tetraploid cells (4c and 2c X 2 cells) was found in this region, both in adult and juvenile frogs. The incidence of tetraploid hypothalamic cells varied among the individuals studied. In some adult frogs as well as in some juveniles no tetraploid cells were detected. The data obtained do not confirm the age related increase in the mean DNA content in frog's hypothalamic cells population.

Animals↗
PubMed1982

[2-wave-length method for the quantitative determination of DNA and histones in the same cell nucleus].

A cytophotometric method is proposed for measuring DNA and histones in the same nucleus after two consecutive cytochemical reactions. Optimum conditions are defined for realization of the reactions. From spectral curves of components under investigation equations are concluded for calculations of DNA and histone contents, according to the data obtained from measuring the optical density of the nucleus at the two specially selected wave lengths. The method ensures receiving results with the same accuracy as ordinary methods of DNA and histone determination.

Animals↗
PubMed1979

[Microspectrophotometric study of the crystalline inclusions in different strains of Amoeba proteus].

Using microspectrometric technique, integral extinction and extinction spectra of crystalline inclusions of two amoeba strains, C and Ct, have been studied. The analysis of extinction spectrum form allowed to suggest that the crystals seen in both amoeba strains have identical chemical composition, whereas the morphological differences between cells in their transparency may be due to different mode of the crystal package. The relative amount of the crystals was measured in both amoeba strains on the basis of the integral extinction value. The distinct differences between the strains were detected in the integral extinction value and in the extinction spectra, which allowed us to use these parameters as genetic markers in the experiments on the nuclear transplantation in amoeba.

Amoeba↗