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Biomedical subjects

L A Semenova

Publications and source records attributed to L A Semenova.

At least 19 recordsLinked to original sources
PubMed2006

Effect of radioprotector indralin on carboplatinum hemotoxicity.

A decrease in carboplatinum hemotoxicity was detected in experiments on C57B1 mice treated with the drug in combination with indralin (urgent radioprotector). Carboplatinum in a dose of 125 mg/kg, injected intraperitoneally, caused 80-100% death; the median term of death was 6 days (3-17). Single oral dose of indralin (100 mg/kg) during the 1st min or 15 min after carboplatinum injection (125 mg/kg) increased animal survival by 40.0-46.7% by day 20 of the experiment primarily during the period of manifest hemotoxicity (days 7-17), indralin injected 1, 2, or 4 h after carboplatinum exhibited no chemoprotective effect.

Animals↗
PubMed2004

Effect of melatonin, ascorbic acid, and succinic acid on the cumulative toxic effect of repeated treatment with gammafos (amifostine).

Daily treatment of outbred albino mice with gammafos in radioprotective doses of 300 and 500 mg/kg for 4 days produced a cumulative toxic effect. This effect was not observed after decreasing the dose of gammafos to 100 mg/kg. Repeated peroral administration of melatonin and ascorbic acid in a dose of 200 mg/kg 30 min before treatment with gammafos reduced its cumulative toxic effect. Succinic acid in a dose of 100 mg/kg was ineffective under these conditions. The cumulative death time for 50% animals receiving gammafos alone or in combination with melatonin, ascorbic acid, and succinic acid was 3.08, 4.29, 4.06, and 2.97 days, respectively.

Amifostine↗
PubMed2002

[Molecular markers of the cervical cancer].

The genome of human papilloma viruses from a high-risk group (HPV types 16 and 18) has been detected in 90% of cervical tumors and, in some cases, in the adjacent normal tissues. The presence of viral DNA is the main molecular marker of this neoplasia. HPV genome may persist in the tumors as episomal and integrative forms at early and late stages of tumor progression. The status of viral DNA and the pattern of its expression are similar in all cells of this tumor cell population and seem to be a marker of tumor cell monoclonality. Antibodies to the products of viral oncogenes E6 and E7 were found only in 35% of the patients with tumor where HPV genome is present. Thus, this criteria cannot be used for diagnostic and prognostic purposes. On chromosome 6 in the cervical tumors, the specific marker of heterozygocity on loci 6p21.3 was found. The marker appears at the precancer stage and may be regarded as a marker of tumor monoclonality. Heterozygocity loss in the specific locus in the region 6q16-21 correlates with tumor progression and suggests that there are potential tumor-suppressor genes in this region of chromosome 6. A group of HPV positive tumors with a hypermethylator phenotype is described. These tumors are characterized by the simultaneous methylation and inactivation of multiple genes, including tumor suppressor genes.

Female↗
PubMed2002

[Residual variation of morphochronometric traits in hybrid tomatoes: analysis and possible mechanism of emergence].

Different expressivity of several morphometric and chronometric traits in tomato plants having similar genetic composition in the identical environmental conditions manifested as genotypic residual variation. Using correlation and artificial neural network analyses, we determined the relationship between productivity and other morphochronometric parameters. It was shown that chronology of the development may be important for the determination of productivity. Random epigenetic modifications independent of environmental factors are considered to underlie the residual variation. The different trait expression in different plants may lead to higher phenotypic diversity of a population characterized by low gene polymorphism.

Chimera↗
PubMed1994

Inherited enhancement of hydroxyl radical generation and lipid peroxidation in the S strain rats results in DNA rearrangements, degenerative diseases, and premature aging.

Previously by selection and inbreeding of Wistar rats susceptible or resistant to the cataractogenic effect of galactose the S and R rat strains differing in the intensity of hexose transport into the animal cells were developed. High level of OH-radical generation and enhanced lipid peroxidation are revealed in the liver and myocardium of the S rats in contrast to the R rats. Data are obtained supporting the view that enhanced generation of OH-radicals within the S rat tissues is due to oxidation and autooxidation of the abundant amounts of monosacharides intensely accumulating in the rat cells. In spite of continuous inbreeding for more than 40 generations and a high rate of homozygosity, numerous DNA rearrangements are revealed in the S rat genomes. Fragility of the S rat cell membranes is detected. Cataracts and other lens lesions, emphysema, tumors, cardiomyopathy-like changes in the myocardium, scoliosis, brain disfunctions are characteristic of the S rats, as well as low fertility and short life-span indicative of premature aging.

Aging↗
PubMed1993

Embryonic stem cells derived from morulae, inner cell mass, and blastocysts of mink: comparisons of their pluripotencies.

A characterization of cell lines that we derived from morulae (three lines), blastocysts (two lines), and the inner cell mass (ICM) is given. The karyotype of all the lines was normal; the genotype of four lines was XX, and four lines were genotypically XY. The pluripotencies and commitment status of the derived lines were estimated. First, there were not less than two-thirds of cells in the populations of the lines derived from morulae and the ICM with both Xs active; 70-100% of cells of the blastocyst-derived lines had one of the Xs in an inactive state. The activity of glucose-6-phosphate dehydrogenase (G6PD) in the lines (genotype XX) derived from morulae and ICM was found to be twofold higher than in lines with genotype XY, and G6PD activity was the same in the blastocyst-derived XX lines and XY lines. Second, when injected intraperitoneally into athymic mice, morulae- and ICM-derived cells gave rise to simple and complex embryoid bodies (EB) resembling to typical "cystic" mouse EBs. Third, when injected subcutaneously to athymic mice, the ICM- or morula-derived cells gave rise to typical teratomas containing derivatives of the three germ layers and components of organogenesis. Comparisons of cell lines of different derivations demonstrated that the pluripotencies of the ES cells derived from morulae or the ICM are higher than those of blastocyst derivation.

Animals↗
PubMed1993

[Myocardial infarction in systemic lupus erythematosus].

Six patients under 50 with confirmed systemic lupus erythematosus (SLE) developed myocardial infarction at different intervals from the disease onset (1-21 years). Five of them had chronic disease, one suffered from acute SLE. The analysis of clinical findings identified myocardial infarction risk factors in SLE (chronic course of the disease, long-term glucocorticosteroid treatment, hypercholesterolemia, persistent nephrotic syndrome, arterial hypertension, vasculitis, hypercoagulation, antiphospholipid antigens) and provided a basis for prevention of this severe SLE complication.

Acute Disease↗
PubMed1992

[Amyloidosis in systemic lupus erythematosus].

Based on the authors' experience from 1982 to 1990 it was noted that out of 26 cases of renal amyloidosis in the presence of nonpurulent and purulent conditions 2 patients (7%) demonstrated the association with systemic lupus erythematosus (SLE). It was also noted that amyloidosis developed in the patients with a long history of the disease. Long-course immunosuppression treatment could be regarded as the other factor-of-risk for amyloidosis development. Histochemical examination of both patients demonstrated that amyloid deposits in the renal glomeruli were resistant to the potassium permanganate effect and consisted of AL-protein. The results obtained indicated the possibility of appearance of immunoglobulins AL--the proteins of the primary amyloidosis--synthesized in the spectrum in the SLE presence as well as their deposition in the renal glomeruli. As a possible cause of proteinuria and the nephrotic syndrome in SLE patients amyloidosis should be diagnosed in the life time and be regarded in the choice of therapeutic policy as well as in the assessment of pulse immunosuppressive therapy practicability.

Adolescent↗
PubMed1991

[Pathomorphology of experimental pneumocystosis and cytogenesis of the pathogen Pneumocystis carinii].

A lung pneumocystosis model has been developed in white non-inbred rats (83 animals). The pathological process develops during 1 month versus 2-3 months in other models. Pathomorphology is in principle similar to human pneumocystosis. Bauer's method appeared to be the simplest and adequate for the detection of mature pneumocysts in the lung sections among many other methods used.

Animals↗
PubMed1990

[Reciprocal differences in the susceptibility to induction by ortho-aminoazotoluene of liver and vascular tumors in A/HeJ and CC67BR/Mv mice].

When administered subcutaneously, ortho-aminoazotoluene induces predominantly liver tumours in A/HeJ mice but vascular tumours (located mainly in the interscapular brown fat pads) in CC57BR/Mv mice. Liver tumours are more frequent in females, while vascular tumours--in males. Under crossing, the susceptibility to induction of the both types of tumours in male F1 hybrids is inherited intermediately, whereas in females the resistance to induction of vascular tumours predominates.

Animals↗
PubMed1990

[Comparative evaluation of the glycosaminoglycan composition in plasma membranes of normal and transformed mouse liver cells].

Using electrophoresis in agarose gel, a comparative study of composition of membrane-bound glycosaminoglycans (GAG) from normal mouse liver cells and from o-aminoazatoluene-induced mouse hepatoma cells was carried out. Differences in the composition and localization of GAG were revealed. The plasma membrane fraction of hepatoma cells contained no GAG; the bulk of GAG (approximately 98%) was localized in the plasma membrane free fraction. Within this fraction GAG contained no heparan sulfates with a high electrophoretic mobility that were detected in plasma membranes of normal liver cells. The possible involvement of proteoglycans bound to cell surface in transmembrane signal transfer is discussed.

Animals↗
PubMed1990

[Different predisposition to the development of spontaneous and induced liver tumors in mice of different strains and their hybrids].

No correlation between the sensitivity to induction of liver tumours by ortho-aminoazotoluene and predisposition to spontaneous development of these tumours was found in mice. Under crossing the predisposition to spontaneous tumours was inherited dominantly, while sensitivity to their induction was inherited by the intermediate type. Spontaneous hepatomas were more frequent in males, whereas induced onesin females of the same genotype.

Animals↗
PubMed1989

[Ultrastructural mechanisms of myocardial atrophy in white rats during starvation].

By means of complex morphological, morphometrical and stereological analyses the myocardium of Wistar rats was studied in full alimentary starvation during 6 days. The availability of two mechanisms of myocardial atrophy in adaptation to full starvation was revealed, these are the diminution of dimensions of parenchymatous elements and the decrease of muscle cell number. By ultrastructural investigation of cardiomyocytes the signs of structural protein synthesis decline were revealed, this is a simple myocardial atrophy. In quantitative analysis of cardiomyocytes the decrease of their number without changes in proportions of cells with different nuclei number was observed, that indicated systematic character of muscle cell elimination out of myocardium by apoptosis mechanism involvement, this is a numerical myocardial atrophy. Stereological analysis of myocardial atrophy development in conditions of full starvation determined the main regulated indices, these are the absolute total myofibril mass and mitochondrial mass and surface area.

Animals↗
PubMed1989

[Stereologic analysis of the myocardium in alcoholic cardiomyopathy].

By methods of light and electron microscopies, morphometric and stereologic analysis the effect of ethanol, thiamine deficiency diet and ethanol combined with B1 hypovitaminosis in 24 Wistar male-rats during 6 weeks was studied. Ultrastructural features of decreasing protein synthesis and carbohydrate metabolism were revealed both in ethanol administration and in B1 hypovitaminosis. There is shown in alcoholic intoxication the statistically significant decrease of capillary volume density and increase of volume density of connective tissue cells in myocardium. It was shown, that B1 hypovitaminosis resulted in decrease of myocardial mass mainly at the expense of volume density and absolute total mass of muscle fibers. The most expressed changes of tissue organization were revealed in combined influence of ethanol and B1 hypovitaminosis.

Animals↗