[Ultrastructure of coronary microvessels in conditions of heart reperfusion following prolonged ischemia while applying various methods of artificial hypothermia].

It has been found out that in children with Roger's disease corrected in the conditions of two fundamentally different procedures of anesthetic management, myocardial reperfusion after cardiac arrest under artificial hypothermic circulation is accompanied by obstruction of more than 30% of coronary bed microvessels with hydropic endothelial cells or their cystiform fragments. The content of necrotic cells increases, while the "working" cells demonstrate a decrease in myocropinocytotic transport characteristics. Circulatory arrest under perfusionless hypothermia and immersion reperfusion do not result in a dramatic change of general morphology of microvessels as compared to the control group, while a heterogenic response of the structures responsible for transendothelial transfer of macromolecules provides the basis for recovery of the endothelium structure and function, as a patient's temperature reaches a standard value.

[Endothelial ultrastructure of myocardium microvessels affected by various methods of artificial hypothermia].

A comparative analysis of the endothelial ultrastructure of myocardium microvessels affected by various methods of artificial hypothermia was carried out. Tissue samples were harvested in children with a congenital ventricular septum defect after cooling the whole body under the conditions of hypothermic artificial circulation and perfusionless (immersion) hypothermia. It was found out that the shifts in population composition of endothelial cells, as well as the changes in the ultrastructure of organelles participating in endocellular syntheses and transendothelial transfer of macromolecules depended upon the rate body cooling. Under perfusionless hypothermia and of moderately low cooling rate, morphological signs of inhibition of endothelial cells metabolism were observed alongside with quantitative reduction of their micropinocytic transport indicators. Under hypothermic artificial circulation these reactions tended to lag behind due to the high cooling rate that initiates a heterogenic response of various endothelial processes to the changes of body temperature.

The choice of the technique for harvesting and preparation of the radial artery for coronary artery bypass grafting.

At present coronary artery disease (CAD) is a most frequently occurring cause of the lethality and disability of patients. One of the basic methods for CAD treatment is coronary artery bypass grafting (CABG). Actuality of the problem of applying the radial artery (RA) for CABG is determined by the proven advantage of arterial grafts versus vein grafts in myocardial revascularization. Today the RA ranks second in frequency of using the arterial graft subsequently to the internal thoracic artery (ITA). The RA may be harvested by two techniques: skeletization and in a case with surrounding tissue. However, to this day there is no unanimous opinion as regards the advantages of one or another approach. Of importance is conduit conservation from the time of harvesting to implantation into the coronary artery position. Despite a great number of conservants offered for conservation before implantation, comparative analysis of their effect on the conduit endothelium was not carried out. The problem of the safety of the RA conduit also remains open to discussion.

[Endothelium of myocardium microvessel under conditions of hypothermia, ischemia, reperfusion and pharmaco-cold cardioplegia with calcium antagonist].

Microvessels of the right atrium endothelium were investigated with electron microscope for patients with congenital heart disease receiving surgical treatment under deep perfusionless hypothermia and various methods of pharmaco-cold cardioplegia. In group 1, pharmaco-cold cardioplegia was performed, with hyperosmolar normopotash solution cooled down to 2-4 degrees C. In group 2, the same solution combined with isoptin, a potash-ion blocker, was applied. It has been shown that during global ischemia, stability of ion gradients on plasmalemma of endothelial cells is impaired, irrespective of the composition of cardioplegia solution. Alongside with this, ultrastructural reactions in group 1 proceed towards hyperosmia of endothelium accompanied by building up a large group of cells following coagulation necrosis. In group 2, by contrast, an intracellular edema progresses. The cardioprotective effect of isoptin, which is able to block Ca2+, manifests itself most vividly at reperfusion, when the blocking of cell potash overload prevents the development of dystrophic and destructive changes in endothelium of coronary microvessels, which present one of the most severe consequences in the process of blood flow recovery in ischemic tissues.

[The role of specific endothelial granules in changes of myocardium microvessel reperfusion at open-heart operations under hypothermia]. / Rol' spetsificheskikh éndotelial'nykh granul v reperfuzionnykh izmeneniiakh mikrososudov miokarda pri operatsiiakh na otkrytom serdtse v usloviiakh gipotermii.

For patients with congenital heart defects, a comparative analysis was carried out of specific endothelial granules and morphological properties of perfusion capacity of microvessels at various stages of reperfusion after prolonged circulatory arrest. At all stages of reperfusion, the quantity of specific granules in microvessel endothelium dramatically dropped, as compared with the control group. At the early stages of reperfusion, the level of granule exocytosis does not lead to any statistically significant changes in perfusion characteristics in the right atrium microvessels, as compared with the control group. Conversely, at the late stages of reperfusion, degranulation of endothelial cells is enhanced, and physiological mechanisms intended to remove the microvessels from circulation are replaced with pathological ones. These results suggest the existence of a threshold in exocytosis of specific endothelial granules, whose exceeding may switch on some pathological mechanisms in blood flow regulation.

[The comparative morphology of the specific endothelial granules in the microvessels of the hypertrophied myocardium in patients with congenital heart defects and in experimental animals]. / Sravnitel'naia morfologiia spetsificheskikh éndotelial'nykh granul v mikrososudakh gipertrofirovannogo miokarda patsientov i éksperimental'nykh zhivotnykh.

Specific endothelial granules of myocardial microvessels were studied in both patients, suffering from different congenital heart pathology, and dogs, before and during hyperthermia. In the intact myocardium of dogs we found two morphological varieties of granules, dark and light ones. The ultrastructural polymorphism of these granules was due presumably to hyperthermia. In cases of heart disease, a third morphological form of granules was revealed in the endothelium of myocardium microvessels in the hemodynamic overloaded heart compartments. These granules were larger and had a lighter matrix and a lesser amount of tubes. The granules are considered to be ultrastructural characters of structural reconstruction in the wall of hypertrophied myocardium microvessels at the endothelial level.

[The ultrastructural characteristics of specific endothelial granules in the myocardial microvessels in congenital heart defects]. / Ul'trastrukturnaia kharakteristika spetsificheskikh éndotelial'nykh granul v mikrososudakh miokarda pri vrozhdennykh porokakh serdtsa.

Specific granules in endothelium of microvessels of the right atrium were studied in 15 patients with congenital heart diseases (Fallot tetrad, defect of interventricular septum and aortal stenosis) aged from 3 to 11 by electron microscopy 2 morphological types of granules, varying in optic density-dark and light ones, were found in all observations. Great number of the light granules young forms was also discovered. Maturity of the latter is associated with the increase of number and density of localisation of tubular structures in the granule matrix. Share of granule-containing endotheliocytes varied significantly depending on the kind of the defect (from 27% in aortal stenosis up to 44% in Fallot tetrad), with number of granules varying from 1 to 37 in profile 1. This demonstrates that granule-producing function of endotheliocytes in congenital heart diseases depends on the load exerted on the region, compensating the disturbed hemodynamics in specific pathology and either on presence or absence of hypoxemia.

[The ultrastructural characteristics of the capillary endothelium from different sections of the canine heart]. / Osobennosti ul'trastruktury éndoteliia kapilliarov raznykh otdelov serdtsa u sobak.

Electron microscopy of auricular and ventricular endothelial blood capillary cells (EC) was performed for two groups of dogs, both at normal body temperature (control) and after cooling up to 28-30 degrees C. Cell organelles involved in synthetic processes were developed more in the auricular EC, and the number of specific granules in these exceeded that in organelles of the ventricular EC. The ventricular transport structures were more numerous and more diverse compared to the auricular ones. These subcellular features retained under hypometabolism induced by cooling. Both common (reduction of organelles involved in synthesis) and different ultrastructural responses to cooling were observed in auricular and ventricular endothelial cells. It is established that under hypothermia the ratio between "dark" and "light" granules in auricular EC remains invariable. At the same time, in ventricular EC the share of "light" granules in this ratio was 4 times more than in the control group. These results suggest an existence of ultrastructural differentiation of auricular and ventricular EC.

[A method of pharmacologic support in experimental operation on the dry heart]. / Metod farmakologicherskogo obespecheniia operatsii na sukhom serdtse v éksperimente.

The method of prolonged (up to 35 min) reversible circulatory arrest at anesthetized dogs consists of body external cooling, main vascular occlusion with cardioplegia, cardiac function recovery and animal body warming. Special reference was made to anesthetic security of the experiment. The method provides the study of hypothermic protective mechanisms, the improvement of surgical techniques up to organ transplantation, as well as the observation of long-term results.

[Characteristics of the ultrastructural organization of the nuclei of somatic cell hybrids]. / Osobennosti ul'trastrukturnoi organizatsii iader gibridov somaticheskikh kletok.

A study was made of the ultrastructure of cell nuclei of two types of hybrid clones obtained from the fusion of Chinese hamster with human skin fibroblasts, and from that of mouse hepatoma cells with mink fibroblasts. In cell nuclei of the eight hybrid clones deep invaginations of the inner membrane, not characteristic of the parent cells, were revealed. Analysis of serial sections, and application of electron microscopic radioautography and histochemistry have suggested that these structures are associated with the nuclear envelope which is necessary for regulating the superfluous chromosome localization in the hybrid nucleus.

[Characteristics of the submicroscopic structure of hybrid clone cells obtained by the fusion of mouse hepatoma cells and mink fibroblasts and containing different numbers of mink chromosomes]. / Osobennosti sumbikroskopicheskogo stroeniia kletok gibridnykh klonov, poluchennykh ot sliianiia kletok gepatomy myshi i fibroblastov norki i soderzhashchikh raznoe chislo khromosom norki.

Four hybrid clones obtained by fusion of mouse hepatoma cells with mink fibroblasts treated with polyethyleneglycol were studied morphologically and morphometrically using electron microscopy. The clones studied contained a double set of mouse chromosomes and different numbers of mink chromosomes. It is demonstrated that clones containing different mink chromosomes differ considerably from each other and from the parental cells in the manifestation of some morphological characters (form and type of cell growth, form of the nucleus, structure of mitochondria, distribution of membranes of the granular endoplasmic reticulum), as well as in some quantitative parametres of organelles (area of the cut of the cell and of the nucleus, a relative volume of the nucleus). The data obtained witness for the fact that some morphological traits characteristic of cells of a certain parental type may appear in hybrids independently of each other, and that the degree of their manifestation may depend on the number of chromosomes of one of the parents or, possibly, on one particular chromosome.

[Incidence of staphylococcal carriage in pregnant women]. / Rasprostranenie stafilokokkovogo nositel'stva u beremennykh.

In 1,494 pregnant women (on weeks 32-36) staphylococcal carriership was studied. One-third of the women under investigation were found to be carriers, their bacterial discharge increasing in spring and summer. The isolated strains proved to be polyresistant to antibiotics and belonged to epidemic strains. About a half of Staphylococcus aureus strains could not be identified with the use of the international set of phages.