[Effects of infusion media on human red blood cell morphology]

The effect of various infusion media on the structure of human red blood cells was evaluated in vitro and in vivo. The in vitro experiments used 10% sodium chloride (NaCl) solution, 10% glucose solution, 20% albumin solution, Rheopolyglucin, HyperHAES solution (18 g of NaCl in combination with 60 g of hydroxyethylstarch (HES), 200/0.5), Voluven (HES 130/0.4/9:1), and a combination of hypertensive NaCl solution and Rheopolyglucin. The morphofunctional response of red blood cells was studied in the clinical setting when 6% Voluven solution (HES 130/0.4/ 9:1) and hypertensive NaCl and glucose solutions were used. It was established that 10% NaCl solution caused considerable changes in the morphology of red blood cells both in the experiment and in patients with severe brain injury. The magnitude of structural changes increased as blood NaCl concentrations became higher. 10% glucose solution, Voluven, Rheopolyglucin, and albumin did not virtually affect the structure of red blood cells. Infusion of Voluven (500 ml of 6% solution for 40 minutes) induced no changes in the morphology of red blood cells in the clinical setting. Among the test solutions used to correct intracranial hypertension (HyperHAES, 10% NaCl, a combination of rheopolyglucin and 10% NaCl), HyperHAES exerted the least effect on the morphology of red blood cells.

[Structural-functional motifs of sterol 14-alpha demethylases (CYP51)]

CYP51 family of cytochromes P450 (sterol 14-alpha-demethylases) comprises the representatives from different kingdoms of living world, thus positioning itself as the most ancient member of the superfamily. In the course of the present research the collection of 36 full-length CYP51 amino acid sequences was submitted to cluster analysis. Each node of the clustering dendrogram corresponds to the groups of proteins, located on the branches descending from the node. By making the multiple alignment of each group of protein sequences we obtained the node-specific consensus sequences. The informational content of the consensus was defined as the presence of the compact conserved sites, the motifs. The assessment of informational content was computed using Sherman's non-parametric statistical criterion. The high informational content was observed for the 100% conserved consensus sequences of the following CYP51,s groups: fungi, animal+plant, plant+protista and bacteria. These selected consensus sequences were next aligned all together to get the final consensus for the whole family. To enrich the informational content of the CYP51 consensus the level of its conservation was dropped to 75%. Regions of statistically significant conservation were unraveled in the CYP51 consensus sequence. These regions (motifs) were then correlated with the information on secondary structure elements and substrate recognition sites reported for CYP51 from Mycobacterium tuberculosis. Seven motifs appeared to be obligatory for every CYP51 protein. The motifs thus obtained were searched for among all the known cytochrome P450 proteins. Some motifs were found to be absolutely specific for 14-alpha-demethylases, whereas others were common to different species of cytochromes P450.

[Intracranial cavernous angiomas: ultrastructural and immunochemical study]

43 brain cavernous angiomas (CA) were clinically and morphologically studied. The presence of smooth muscles and endotheliocytes in the trabeculae was confirmed. The sources of blood supply and the nature of medullary changes at the CA periphery were clarified. The hypothesis of CA hormonal dependence has been rejected.

Cytochrome P450 database

This paper describes a specialized database dedicated exclusively to the cytochrome P450 superfamily. The system provides the impression of superfamily's nomenclature and describes structure and function of different P450 enzymes. Information on P450-catalyzed reactions, substrate preferences, peculiarities of induction and inhibition is available through the database management system. Also the source genes and appropriate translated proteins can be retrieved together with corresponding literature references. Developed programming solution provides the flexible interface for browsing, searching, grouping and reporting the information. Local version of database manager and required data files are distributed on a compact disk. Besides, there is a network version of the software available on Internet. The network version implies the original mechanism, which is useful for the permanent online extension of the data scope.

[The ultrastructural changes in the collagenous-elastic skeleton of the wall of the cerebral vessels in spasm in the acute period of a subarachnoid hemorrhage]

Electron microscopic study of arteries in spasm and ischemia of the brain revealed substantial ultrastructural changes in the vascular wall. The changes are characterized by varying thickness, edema, dissociation of fibrillar and amorphous components of internal elastic membrane of the arterial wall, by lesion in the network of collagen fibers on its inner surface, by the presence of defibrotic and uncoiled collagenous fibers of the adventitia. The changes are followed by the impairment of the arterial skeleton and hence they lead to their altered elastic properties.

[Alpha-fetoprotein suppresses keratinocyte proliferation 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 characteristics of the absorption in the small intestine of 2 casein hydrolysates and of an equivalent amino acid mixture]

Using casein hydrolysates and the amino-acid mixture applied to mucosal or serosal surfaces, their effect on the transport of free glycine, glycine formed during glycyl glycine hydrolysis, and galactose, was studied in the small intestine. The data obtained suggest a mechanism of peptide transport in the enterocytes as well as a possibility of a regulatory effect of the peptides contained in casein hydrolysates on the transport of some basic nutrients.

[The hydrolases of the mucosal, submucosal and muscular layers of the small intestine and their functions]

Proceeding from the newly obtained evidence on the distribution of digestive enzymes in mucosal, submucosal and muscular layers of the small intestine in rats, a hypothesis has been formulated: in addition to the enterocyte enzyme complex forming the epithelial barrier, there seems to exist a postepithelial barrier formed by the enzymes localized in subepithelial structures. The efficiency of this second barrier was manifested by the study of the peptide hydrolysis and transport using everted intact and de-epithelialized intestinal sacs.

[Morphological substantiation of selection of the method of surgical treatment of patients with prolapse of internal genital organs]

Morphology of uterine ligaments and the vaginal mucosa has been examined in 61 patients with uterine prolapse in order to provide guidelines for an optimum management with respect to tissue functional status. Specimens were obtained intraoperatively and examined in a usual microscope and a S-570 Hitachi scanning electron microscope (Japan). The study suggests that morphologic evaluation of the vaginal walls and uterine ligaments provides an exact measure of tissue status, offering an optimum choice of treatment in these patients.

[Laser irradiation: study of general and local mechanisms of its action in irradiation of the eyeball. An experimental study. 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.

Localization of peptide hydrolysis in the enterocyte and the transport mechanisms of apical membrane

1. The absence of the effect of anoxia on the hydrolysis rate of a number of dipeptides and one tripeptide by the intact and homogenized mucosa of the small intestine in different mammals (rat, mouse and guinea pig) has been demonstrated. 2. It has been shown that in rats anoxia inhibits intestinal transport both of free glycine and glycine formed during the hydrolysis of Gly-Leu, Leu-Gly, Gly-Pro but not Pro-Gly. 3. Data obtained using the anoxic criterion suggest that the systems of membrane hydrolysis of peptides with the subsequent absorption of released amino acids presents a dominant mechanism of protein assimilation under normal physiological conditions. 4. However, they do not exclude the possibility of the transport of peptides across the apical membrane of enterocytes.

Normal-incidence multilayer mirrors for the 120-450 å wavelength region

An electron-beam deposition method is used to fabricate spherical and flat mirrors with a peak reflectivity of 20% for wavelengths between 120 and 450 Å. It is experimentally shown that the fabricated mirrors can be employed to form an image with a resolution of 1 μm for ultrasoft x rays. The possibility of producing intense directional high-temperature plasma radiation by spherical multilayer mirrors is demonstrated. A radiation intensity of 107 W/cm2 around 182 Å has been experimentally obtained in the laser plasma image plane.

[Identification of digitonin binding sites on the plasma membrane of the rabbit aorta endotheliocytes]

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.

[The phenomenon of the accumulation of biological and nonbiological corpuscular particles in mammalian lungs]

When injecting yeast, staphylococcus, polyacrolein microspheres, 3 microns in diameter, into the blood stream of white common rats, it was found that these tend to accumulate in the lumen of pulmonary capillaries, being disposed there in the cytoplasm of macrophages and neutrophils.

[Cholesterol in the plasmalemma of endotheliocytes in the normal aorta and in hypercholesterolemia (scanning electron microscopy research)]

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]

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]

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.

[Regional characteristics of the organization of the aortic endothelium (a quantitative analysis)]

By means of SEM-analysis in 110 microphotos (from 14 aortas of white rats) with the aim to estimate heteromorphism of the thoracic part endothelium, quantitative characteristics of endotheliocytes have been studied in the ventral and dorsal surfaces, and also around the ostia of the intercostal arteries. For the quantitative analysis organization of the lines of the interendotheliocyte borders is taken into account. Endotheliocytes around the ostium are more elongated but occupy less area and have less straight contours in comparison with cells in other regions; they have also greater variability. Essential differences in arranging the endothelial cells into the layer on the ventral and dorsal surfaces of the aorta are revealed.

[Pathogenesis of cardiovascular disorders in acute experimental arterial obstruction]

Agents producing toxic myocardial effects are shown to appear in systemic blood flow as a result of acute occlusion of aortal trifurcation with subsequent recovery of blood flow in the limbs. The most pronounced effect was noted following blood infusion in dogs whose ischemia of the limbs had lasted for nine hours, instead of twelve, which must be due to specific features of circulation recovery in the ischemic area.