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Biomedical subjects

B Ia Ryzhavskiĭ

Publications and source records attributed to B Ia Ryzhavskiĭ.

At least 19 recordsLinked to original sources
PubMed2005

[Peculiarities of ovarian and adrenal histophysiology in female rats producing the offspring with an accelerated brain development].

The purpose of the present study was to determine what peculiarities of endocrine and reproductive systems of female rats may favor the birth of the offspring with an accelerated brain development. The study included 20 female rats examined 1 day after the parturition and their 1-day-old offspring (n = 201). In females the activity of 3b-hydroxysteroid dehydrogenase (HSD) and lipid concentration were determined in ovarian steroid-producing structures and in all the zones of adrenal cortex. Estradiol and triiodothyronine concentrations were measured in blood and the prenatal mortality of the offspring was determined. In newborn rats the brain mass, neocortex and its layer I thickness were measured as well as the numerical density of neurons in layer V. Using the method of cluster analysis, newborn rats and their mothers were divided into 3 groups, depending upon the degree of brain development of the offspring. It was shown that an accelerated brain development was associated with somewhat smaller number of newborn rats per litter, an increased prenatal fetal loss, and lower HSD activity in ovarian and adrenal cortex steroid-producing cells, low estradiol concentration in blood. It is assumed that these peculiarities of maternal endocrine and reproductive systems could cause a higher level of brain development in their offspring.

3-Hydroxysteroid Dehydrogenases↗
PubMed2004

[Morphological and cytochemical features of the gingival mucosal epithelium in women during different phases of the menstrual cycle].

Morphological analysis of smears of the gingival epithelium by computer-aided morphometry was carried out in women during the secretory and proliferation phases of the menstrual cycle. During the secretory phase the cell ratio was characterized by higher percentage of epitheliocytes in the terminal stages of differentiation. Size of the nuclei and cytoplasm of intermediate cells, concentration of total protein in them, number of the nucleolar organizer zones, and degree of bacterial contamination of epitheliocytes is higher during the secretory phase than during the proliferation phase.

Adult↗
PubMed2004

[A comparative morphological description of the gingival and buccal epithelium in females in various phases of the menstrual cycle].

Computer morphometry was used to analyze morphologically and histochemically the smears of the gingival and buccal epithelium obtained from women at the secretion and proliferation phases of the menstrual cycle. A variety of reliably statistic differences conditioned by a menstrual-cycle phase was found to be typical of the gingival epithelium. A high percentage of epitheliocytes of differentiation terminal stages as well as signs of enhanced protein-synthesizing processes were typical of the cells ratio in the gingival epithelium at the secretion phase. The number of differences in the buccal epithelium conditioned by a menstrual cycle was by far less, which denotes a lesser dependence of this epithelium on hormones, whose concentration at the proliferation phase essentially differs from that observed at the secretion phase.

Adult↗
PubMed2003

[Comparative morphofunctional characteristics of the ovaries in women of reproduction age in the norm and with chronic anovulatory infertility].

This work was aimed at the study of ovarian histophysiology in patients with chronic anovulation. The biopsy specimens obtained by endoscopic laparoscopy from the ovaries of women of reproductive age with anovulation or normal cycle (control) were examined. It was found that in the ovaries of anovulation patients the thickness of both tunica albuginea and follicular theca externa was increased. The number of primordial follicles was not different in groups studied, while the number of antral follicles was decreased in anovulation group. No differences in 3 beta-hydroxysteroiddehydrogenase and NADH-dehydrogenase activities in the cells of theca interna and cyst walls were found in both groups, while NADPH-dehydrogenase and NO-synthase activities in these structures were reduced in anovulation. Reduction of estradiol concentration and increase of testosterone concentration were noted in blood of women with anovulatory infertility. The data obtained can be used for the analysis of etiology and pathogenesis of anovulatory infertility and for development of the methods of its treatment.

Adolescent↗
PubMed1999

[Comparisons of brain weight and neocortical thickness in 21-day-old fetuses and 1-day-old rats with the histophysiological indices of the ovaries and adrenal glands of their mothers (a correlational and cluster analysis)].

The correlation and cluster analysis revealed that the brain weight of the rat 21-day-old foetus obviously depended on 3 beta-hydroxysteroiddehydrogenase activity in adrenal cortex. No such dependence was found in 1-day-old foetus. Thickness of the brain cortex in 21-day-old foetus and in 1-day-old rat correlated with parameters of the enzyme activity in the corpus luteum, corpus atretic, and theca folliculi of mother's ovaries.

3-Hydroxysteroid Dehydrogenases↗
PubMed1995

[The ultrastructure of the cord blood lymphocytes of newborn infants in normal and complicated pregnancies].

Ultrastructure of the umbilical cord blood lymphocytes was studied in full-term newborns with mothers suffering from toxemia (nephropathy) of the pregnancy second part and without any pathology, in part-term newborns and adult donors. Lymphocytes demonstrated in newborns were the same as in adults (small light, small dark, medium and large ones) with their ultrastructure close to that of adults. Morphometric analysis revealed signs characteristic for newborn lymphocytes. Second and third group newborns were found to have pathological changes in part of lymphocytes concerning both nucleus and cytoplasm and also some morphometric peculiarities. They are manifested as different in expression and direction in different types of lymphocytes of absolute and relative square of mitochondrial section and as signs of synthetic processes activation in all types lymphocytes.

Adult↗
PubMed1993

[Morphofunctional features of the ovary remaining after unilateral ovariectomy in various stages of the sexual cycle and during pregnancy].

The activity of 3 beta-ol-steroid-dehydrogenase in yellow bodies, theca, athretic bodies of hemi-ovariectomized rats and the mass of steroid-producing ovary structure during diestrus, estrus on the 8th, 20th days of pregnancy was studied. The findings about progesterone concentration, number and mass of fetus and placenta in hemi-ovariectomized rats as those in control are presented.

Animals↗
PubMed1993

[The morphological characteristics of the brain in 20- to 21-day-old embryos and 1- and 5-day-old rats].

Absolute and relative brain mass, specific rate of its growth, hemispheric cortex thickness, neurocyte distribution in the second and fifth cortical layers were investigated. A positive relationship between body mass and absolute brain mass was revealed in 21-day embryos and 1-day-old rats. Correlation coefficient between the values in 20-day embryos and 5-day-old rats was 0.2-0.3 (p > 0.05). All age groups showed a reliable correlation between relative brain mass and body mass. Both the parameters differed much in animals of the same age and sex and even within the same litter. Rate of brain growth was the highest during days 1-5 and the lowest between embryogenesis day 21 and day 1 of life, and higher in males than in females. Brain cortex was thicker in 5-day-old males than in females; this parameter varied within a wide range in all age groups. Neuron distribution density in the second layer decreased by the first day of life, that in the fifth layer by day 5 of life.

Animals↗
PubMed1992

[The effect of chemical damage to the adrenal cortex on its ontogenetic development].

We studied adrenal gland of rats at the age of 1 month, which underwent injections of dioxin-preparations during a week. In 1, 6, 12 days; 1, 3, 5, 5, 7, 13 months adrenal gland mass, adrenal cortex size, adrenocorticocytes number, 3B-ol-steroid dehydrogenase and succinate dehydrogenase activities of the experimental animals differed greatly from that of the control. It was found that chemical damage of the gland at an early stage changes it greatly during the following ontogenic development.

Adrenal Cortex↗