[Alpha-fetoprotein suppresses keratinocyte proliferation in vitro]. / Al'fa-fetoprotein podavliaet proliferatsiiu keratinotsitov in vitro.

The influence of alpha-fetoprotein (AFP) on the proliferation of human epidermal keratinocytes in vitro has been studied. AFP (1p microgram/ ml) inhibits the proliferation of keratinocytes cultivated in a serum-free medium. The addition of fetal bovine serum significantly enhances the effect of AFP in this culture. A similar effect of AFP is observed in a medium with a low content of calcium ions.

[The cholesterol content of biomembranes (an electron microscopic study)]. / Izuchenie soderzhaniia kholesterina v biomembranakh (élektronno-mikroskopicheskoe issledovanie).

A new specific cholesterol marker and scanning electron microscopy were used to study the quantity and distribution of cholesterol in the artifical phospholipid membranes and in the plasmalemma of animal and human endotheliocyte and erythrocytes in health and in hypercholesterolemia.

[The detection of the cholesterol of the erythrocyte plasmalemma by using a latex marker]. / Vyiavlenie kholesterina plazmalemmy éritrotsitov s pomoshch'iu lateksnogo markera.

Using a new specific cholesterol marker (SCM) and scanning electron microscopy, the distribution of cholesterol in the plasmalemma of rabbit and human erythrocytes was studied. Investigation of SCM linking with the erythrocyte membranes with different cholesterol/phospholipid indices shows that the increase of cholesterol/phospholipid index of the erythrocyte membrane correlates with the increase in the number of SCM particles on the erythrocyte surface.

[Laser irradiation: study of general and local mechanisms of its action in irradiation of the eyeball. An experimental study. 3]. / Lazernoe izluchenie: issledovanie obshchego i mestnogo mekhanizma deistviia pri obluchenii glaznogo iabloka. Eksperimental'noe issledovanie. Soobshchenie 3.

Rabbit ocular tissues, brain, and blood were examined before and after irradiation of the eyeball with He-Ne laser. Scanning electron microscopy, radioimmunoassay, and biochemical methods were employed in the study. The findings evidence that irradiation of the eyeball results in reduced lipid peroxidation activity and elevated antiradical defense enzymes activity not only in ocular tissues but in the corresponding brain hemisphere and blood, which fact appears to be due to direct effect of laser radiation on the blood and brain via the optic nerve that may be a light conductor for a certain wavelength. Local increase of the eyeball corneal permeability in laser irradiation may be explained by activation of membrane phospholipases, combined with electrolyte shifts; morphologically and functionally it manifests by changed endotheliocyte stereotopography.

[Identification of digitonin binding sites on the plasma membrane of the rabbit aorta endotheliocytes]. / Identifikatsiia digitoninsviazyvaiushchikh uchastkov plasmaticheskoi membrany éndoteliotsitov aorty krolika.

Specific reagents comprising digitonin bound to latex spheres were used as visual markers for the detection of cholesterol sites on the endothelial cell surface by scanning electron microscopy. The distribution of latex markers in the plasmolemma of the endothelial cells was investigated. These markers have strong bonds with the ligands. This interaction guarantees high specificity of binding between labeled markers and cellular membrane cholesterol.

[Cholesterol in the plasmalemma of endotheliocytes in the normal aorta and in hypercholesterolemia (scanning electron microscopy research)]. / Kholesterin v plazmolemme éndoteliotsitov aorty v norme i pri giperkholesterinemii (skaniruiushchee élektronno-mikroskopicheskoe issledovanie).

Using a specific latex marker (SLM) and scanning electron microscopy, distribution of cholesterin in plasmolemma of endotheliocytes of the thoracic part of the rabbit aorta has been studied under normal conditions and at experimental atherosclerosis, as well as on the surface of liposomes and flat bilayer films. SLM reacts with a high specificity directly with cholesterin of the membrane. When studying microtopography of cholesterin, it is possible to distinguish microdomains with various density of distribution of SLM particles. Amount of SLM per 1 mcm2 of the artificial membrane surfaces grows at increase of the cholesterin-phospholipid (Ch/Phl) index of the membrane; Ch/Phl can bind with the membranes beginning only with the threshold value of the Ch/Phl index equal to 0.5. At hypercholesterolemia amount of SLM on the luminal surface of plasmolemma of the aortal endotheliocytes increases by 78%. Hence, at hypercholesterolemia in the luminal part of plasmolemma of the aortal endotheliocytes the Ch/Phl index increases; this should be taken into consideration, when observing mechanisms of reorganization of the endothelial cells layer at atherosclerosis.

[The distribution of negative charges on the luminal surface of Descemet's endothelium]. / Raspredelenie otritsatel'nykh zariadov na liuminal'noi poverkhnosti destsemetova éndoteliia.

The localization of anionic sites on the surface of corneal endothelium was investigated using colloidal nickel. The distribution of the binding sites of colloidal nickel along the cell surface was examined with the scanning electron microscope. The application a special detector of high sensitivity reflection allows to register a composed contrast determined by colloidal nickel. Colloidal nickel is bound with the surface of endothelium in areas of cell junctions only. A 1 X 10(-4)% sol. adrenaline injection into the anterior rabbit eye chamber in vivo changed the distribution of colloidal nickel. These findings demonstrate that colloidal nickel allows to mark the anionic sites on the cell surface for scanning electron microscopic studies.

[Detection of the intercellular borders of the endothelium using scanning electron microscopy]. / Vyiavlenie mezhkletochnykh granits éndoteliia s pomoshch'iu skaniruiushchei élektronnoi mikroskopii.

Three different approaches for studying aorta endothelial cells by scanning electron microscopy (SEM) were compared to expose cell border lines and surface shape simultaneously. Staining of aorta probes with silver nitrate leads to more specific silver deposits at cell junctions, but unsatisfactory image resolution obscures any detail of cell junctions and other fine structural features. Endothelium impregnated with tannin-osmium showed enhanced cell junction detail, but this method resulted in formation of presumably artificial structures. Osmium tetraoxide was most optimal for impregnation of aorta probes, as it exposed well cell border lines, excluded artifacts of tannin-osmium staining, provided a good image resolution in SEM, and allowed to analyse the ultrastructural features of cell surface.

[Scanning electron microscopy of injected replicas in the study of the vascular system of the liver in mice and rats]. / Skaniruiushchaia élektronnaia mikroskopiia in"ektsionnykh replik v izucheniii sosudistoi sistemy pecheni myshei i krys.

Three-dimensional organization of the liver vascular bed in (C57B1/6 X CBA)F1 mice and rats was examined by scanning electron microscopy of injection replicas. The data have been obtained on the character of branching, diameter of injection replicas in arterial and venous vasculature and different types of microvascular surface relief, depending on their location in the vascular bed.

[Morphogenic role of the underlying substrate of endothelial and mesothelial cells]. / O formogennoí roli podlezhashchego substrata éndotelial'nykh i mezotelial'nykh kletok.

Endothelial and mesothelial cell form, cell surface microrelief and intercellular contacts were studied by scanning electron microscopy. The pattern of the underlying substrate (geometry and expressiveness of basal membrane) is shown to influence the endothelial and mesothelial cell morphology. The morphogenic role of the underlying substrate is discussed.

[Dynamics of the structural transformations of the microcirculatory bed of growing and atretic ovarian follicles]. / Dinamika strukturnykh preobrazovanii mikrotsirkuliatornogo rusla rastushchikh i atreticheskikh follikulov iaichnikov.

Synchronized populations of growing and atretic cavitary follicles in the ovaries of prepubertal mice were produced by administration of serum gonadotropin. Light and electron microscopy with the use of morphometric analysis revealed a definite correlation between the size of the follicles and their vascularization in the course of growth and atresia. The evidence obtained suggests the leading role of the microcirculatory bed initiation of atresia.

[Action of histamine on the aortic endothelium]. / Deistvie gistamina na éndotelii aorty.

Changes of the shape and surface of aortal endotheliocytes under the effect of histamine were studied by scanning electron microscopy. Incubation of fragments of the aorta in a histamine solution for 1 min results in changes of the nucleus-containing zone of some portion of the endotheliocytes into a spindle shape. The surface of the peripheral zone was characterized by the presence of spherical swellings. In some parts of the marginal zones of the cells there were numerous stomata of various sizes. Incubation of aorta for 5 min resulted in considerable alterations in the endotheliocyte stereoultrastructure. The nucleus- containing zones strongly protruded into the lumen. The cells became spherical. The peripheral zone was perforated by numerous stomata. The cell edges separated markedly at contact sites. The results suggest that the mechanism of the observed changes in the shape and surface of the cells may be associated with activation of the cytoskeletic complex (microtubules, microfilaments) under the effect of histamine.

[Ultrastructural changes in the nephron during ischemia and organ "survival"]. / Ul'trastrukturnye izmeneniia vi nefrone pri ishemii i "perezhivanii" organa

Ultrastructural analysis of the epithelium of the proximal and the distal portions of the kidney nephron of albino rats in "survival" of the organ in the cadaver and in experimental ischemia showed a different reaction of the cells to these actions. An intracellular edema and characteristic changes in the ultrastructure of the mitochondria appear in the tubular epithelium during the organ autolysis in the animal cadaver. Under conditions of experimental ischemia, against the background of intracellular edema, there develop marked changes in the lysosomal apparatus of the cells, swelling of the mitochondria and also a marked dilatation of the cysternae of the endoplasmic reticulum and of the Golgi complex.