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S I Kolesnikov

Publications and source records attributed to S I Kolesnikov.

At least 19 recordsLinked to original sources
PubMed2005

[Problems of evolution of extraembryonic organs].

Complex of extraembryonic organs is a special functional system that is one of the earliest to arise in ontogenesis. Fetal development significantly depends upon successful ontogenesis of its extraembryonic organs, which possess their special evolutionary history. What are concrete mechanisms of "adjustment" of a developing organism to the requirements of an environment, which in many respects is new in comparison with those conditions that existed during the ontogenesis of parental forms? Authors believe that it is very promising to look for their morphological manifestations at the level of placenta which is the collector of homeostatic mechanisms. Taking into considerations the rapid course of noosphere evolution, the determination of the strategy of the evolution of the "mother-extraembryonic organs-fetus" system at all the stages of its formation, remains an urgent issue. However, the problem of interrelations between the extraembryonic organs both during their morphogenesis and, especially, in already formed extraembryonic provisional complex often escapes the attention of researchers. This article presents the examination and analysis of phylogenetic history of formation and integration of extraembryonic organ complex. The problems, perspectives and possible mechanisms of their evolutionary transformations are discussed. It appears that at placental level, the mechanisms of co-adaptation of maternal and fetal organisms are realized by trial-and-error process. Placenta plays a role of molecular peacemaker between these organisms. Specific mechanisms, in our opinion, have a clonal-selection nature, that is based on the phenomenon of an alternative splicing. Morphological equivalent of clonal diversity is associated with an enormous number of variations of morphotypes of cell nuclei at the level of trophoblastic elements with the reduction of this variability during their normal development. However, it must be preserved under conditions of ill-being as a morphological reaction, indicating the continuing search for new clones.

Animals↗
PubMed2001

Study of the pathogenesis of Ebola fever in laboratory animals with different sensitivity to this virus.

Pathophysiological parameters were compared in animals with different sensitivity to Ebola virus infected with this virus. Analysis of the results showed the differences in immune reactions underlying the difference between Ebola-sensitive and Ebola-resistant animals. No neutrophil activation in response to Ebola virus injection was noted in Ebola-sensitive animal. Phagocytic activity of neutrophils in these animals inversely correlated with animal sensitivity to Ebola virus. Animal susceptibility to Ebola virus directly correlated with the decrease in the number of circulating T and B cells. We conclude that the immune system plays the key role in animal susceptibility and resistance to Ebola virus.

Animals↗
PubMed2000

Effect of 3,4-benzopyrene on ultrastructure of sinusoidal cells of the liver in adult male rats.

Reorganization of sinusoidal cells (endotheliocytes, Kupffer cells, and Ito cells) in the liver microregion of male rat liver exposed to 3,4-benzopyrene was studied. Synchronous activation of the lysosome-vacuole systems in Kupffer cells and endotheliocyte indicates cooperation of these cells in detoxification of benzopyrene and its metabolites. Ito cells lose lipid inclusions and actively proliferate; the appearance of intermediate forms between lipocytes and fibroblasts attests to activation of fibrogenesis in the liver.

Animals↗
PubMed1998

Immunocytochemical and In situ hybridization studies of the distribution of calbindin D9k in the bovine placenta throughout pregnancy.

The fetus must transport considerable and increasing amounts of calcium across the placental trophoblast epithelium to support growth and development and bone formation. Active calcium transport across epithelia has been shown to correlate with calbindin D9k or 28k content. This study examined the distribution of calbindin D9k (9CBP) protein and mRNA during pregnancy in the bovine placenta to determine its possible role in calcium transport in this system. The immunocytochemical results show 9CBP in an increasing percentage of interplacentomal uninucleate trophoblast cells until, at term, all show a level at least eight times that of any other placental cell. There is a similar, although smaller, rise in their 9CBP mRNA content. The mature interplacentomal binucleate cell ( approximately 5% of the total) contains no 9CBP at any stage of pregnancy. In interplacentomal uterine epithelium, 9CBP protein and mRNA decrease to zero in late pregnancy but the glands maintain constant low levels throughout. In the placentome trophoblast, uninucleate cells show insignificant amounts but binucleate cells (15-20% of the total trophoblast cells) contain considerable levels of both 9CBP protein and mRNA, as do all the uninucleate uterine epithelial cells. The placentomal binucleate cells show peak values at mid-pregnancy; the placentomal uterine epithelium shows only small changes in levels in the second half of pregnancy. Increase in fetal calcium demand in the second half of pregnancy therefore correlates with a major increase in 9CBP only in the interplacentomal trophoblast, as we have also shown in the sheep and goat, indicating an important role for this region in active calcium transport by the ruminant placenta. The 9CBP is distributed uniformly in the cytosol and nucleoplasm, supporting a role in facilitated diffusion of calcium through the cell rather than a vesicular shuttle system.

Animals↗
PubMed1996

[Infectious morbidity in technogenic environmental pollution].

Technogenic environmental pollution has a marked indirect influence on the growth of infection morbidity. While comparing areas with different technogenic loads, the most significant differences in the levels of morbidity were noted in the period of minimal epidemic process intensity. This period was the most susceptible link of an epidemiological year.

Environmental Pollution↗
PubMed1995

Distribution of colloidal gold tracer within rat parasternal lymph nodes after intrapleural injection.

BACKGROUND: Tracer studies are an important tool to obtain information about the processes involved in the immunological response. Colloidal gold is widely used as a tracer, but its small size of label can cause some difficulty during low-resolution analysis. To overcome this difficulty, we developed a new method to follow the route of tracer movement within lymph nodes. METHODS: We applied conventional X-ray analysis, X-ray fluorescence analysis (XFA) subtractional microscopy using synchrotron radiation (SR) beams, light microscopy, and ultrastructural analysis to study the distribution and quantity of colloidal gold coupled with albumin within rat parasternal lymph node 2, 4, 6, 8, and 10 h after intrapleural injection of the tracer. RESULTS: At all the time points XFA-SR revealed that tracer formed a circle with a maximum concentration in the node periphery. XFA-SR measured colloidal gold concentration in the nodes reached its maximum (0.5-0.75 weight %) in 6-8 h. Subtractional microscopy revealed superficially located groups of cells filled with colloidal gold tracer. Light microscopy and ultrastructural analysis confirmed that the tracer was concentrated in the reticular cells, situated in the sinuses of the node. Sinusoidal reticular cells concentrated tracer at much higher rates than sinusoidal macrophages. Four hours after injection, gold appeared in the lysosomes of the follicular reticular cells. At the same time point, evidence of antigen presentation was obtained. Antigen presentation proved to be an extremely rara event since only one ultrastructural incident was found in 150 analysed grids. CONCLUSIONS: SR is a valuable tool for the analysis of gold tracer passage within the living organism.

Animals↗
PubMed1994

[The effect of the activation of lipid peroxidation on the structure of extraembryonic organs and the liver in rats at different periods of ontogeny].

The influence of activation of lipid peroxidation (LP) on morphofunctional organization of extraembryonic compounds and liver on different stages of rat's ontogenesis was studied. It is found that LP-activation (paraquat injection) in late pregnancy leads to extensive vacuolization of trophoblastic and yolk sac cells. In the embryonic liver, the number of hemopoietic cells decreases. During the first days after LP activation in the liver of adult animals, enlargement of granular endoplasmic reticulum elements and their degranulation were revealed. In the liver cells of the offsprings, administered paraquat prenatally, signs of bile formation activation were detected.

Animals↗
PubMed1993

Histochemical localization of oxidized glutathione-catalysing enzymes in human term placenta.

This paper reports a new cytochemical affinity technique for detecting oxidized-glutathione-binding enzymes by light microscopy and for carrying out fine structural analyses by means of oxidized glutathione labelled with colloidal gold. Albumin-colloidal gold particles were prepared. Oxidized glutathione, added to the solution, replaced albumin on the surface of the gold, thus forming a new histochemical reagent. In human placenta, oxidized-glutathione-catalysing activity was detected on the brush border of the placental villi, over the foldings of endothelial membranes, and in the ground substance of connective tissue in the villous core. Every process of the cell membrane demonstrated enhanced oxidized-glutathione-catalysing activity. This new reagent is a unique example of a low-molecular-weight compound labelled with colloidal gold, and it permits direct measurement of oxidized-glutathione-binding activity in tissue sections.

Albumins↗
PubMed1992

[The marker histochemical detection of glucose-6-phosphate residues in the human placenta].

Glucose-6-phosphate residues were revealed by fine structural analysis using glucose-6-phosphate dehydrogenase-gold conjugate. In human mature placenta specific staining was detected over the stroma of placental villi. Colloidal gold particles were found over the collagen fibrils and reticular lamina of basal membrane. Syncytiotrophoblast cells, fibroblasts, endothelial cells of fetal capillaries avoided labelling. Nucleated blood cells and thrombocytes inside the lumen of fetal capillaries demonstrated intense staining. The present investigation demonstrates histochemically the process of extracellular glycosylation. Glycated collagen fibrils formed channels inside the stroma of placental villi.

Biomarkers↗
PubMed1992

[The detection of albumin intraperitoneally administered to rabbits in the subclavian lymph node].

With light and electron microscopy, the localization of human albumin labeled with colloidal gold is described in the subclavia lymph nodes of rabbits following an intraperitoneal injection of this labeled albumin. Most of the particles were found in the reticular cells of the sinus, and some particles were identified in the sinus macrophages. No particles were found inside lymph node follicules within 1 hour after injection. All stages of internalization of foreign protein inside lymph node cells were demonstrated.

Animals↗
PubMed1991

[Immunohistochemical localization of cytochrome P-450].

Distribution of different forms of cytochrome P-450 (forms C, D and B) in human placenta by immunohistochemical methods on light microscopy level with colloid gold was studied. Positive reaction with cytoplasm of endothelial cells, called the "epithelioid" plates of chorionic villi was found. Trophoblastic and stromal cells were not stained.

Chorionic Villi↗
PubMed1991

[Morphological evidence of the possible role of cytochrome P-450 in the development of an autoimmune process in the liver].

Morphological alterations in rat's liver during lipid peroxidation induction by paraqat were studied. Infiltration of liver by lymphocytes, macrophages and plasma cells was studied. On ultrastructure level profound extension of rough reticulum cistern and destruction of mitochondrial cristae were revealed by immunohistochemical methods. Cytochrom P-450 was localized on the fibrin fibers.

Animals↗