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Biomedical subjects

Iu A Romanov

Publications and source records attributed to Iu A Romanov.

At least 19 recordsLinked to original sources

[On some basic issues and factorial structure of ecological pulmonology].

Consideration is given to the place occupied by diseases of respiratory organs in the general structure of morbidity. In many ways, growth in their number has been determined by amplification of anthropogenic factors. This is manifested in emergence of new eco-dependent diseases and syndromes including more difficult course of pulmonary pathology. One of the prioritized disciplines of the modern pulmonology is ecological pulmonology which lies in the domain of medical ecology and is central to the concept of eco-dependent human diseases. A factorial structure of ecological pulmonology built on the etiological principle is proposed to facilitate inquiry into the origin and course of various forms of eco-dependent pathology of the lung.

Adolescent↗

[Alterations in actin cytoskeleton and rate of reparation of human endothelium (the wound-healing model) under the condition of clinostatting].

Effects of long-term simulation of hypogravity on actin cytoskeleton and cell migration were investigated in cultured human endothelium cells (EC). In control, F-actin resided predominantly on the periphery of cell forming an array of parallel bundles with "dense bodies" along the edge. A small number of actin cable fibers was found in the center. Already after 1-2 hrs of clinostatting at 5 RPM the cell cytoskeleton showed actin filament thinning and displacement toward the cell edges. In subsequent 6-18 hrs, almost all actin fibers had left the center part of EC and had ranged themselves in a continuous F-actin line in the intercellular contact area. In most cases, these changes resulted in the so-called "ruff-edge". Since both the disappearance of cable fibers and formation of the "ruff-edge" add to the cell migration activity, this parameter was studied with the would-healing model. According to our data, 24-48 hrs of exposure to hypogravity stimulates cell migration and expedites 2-3 times reparation of mechanically damaged monolayer. The results suggest that effects of hypogravity on cultured human EC are likely to be consequent to alterations in the activity of protein kinase C and/or adenylate cyclase involving many members of the cellular metabolism.

Actin Cytoskeleton↗

[Chrono-ecological analysis of population health and ways of its recreation].

Reported are results of multiyear observation of the structure of individual and population health in Vladikavkaz, and the authors' concept of health recovery and protection through application of modern high technologies of active chronoadaptation to extreme living conditions. The proposed methods of active chronoadapation, i.e. phytocorrection and phytopro-phylaxis, reflexocorrection, bioradiological correction, bioresonance chronolasercorrection can be also of interest for aerospace medicine.

Adaptation, Physiological↗

[From chronobiology to chronotopobiology].

Based on the data available in the literature and his own findings, the author presents a concept of the spatial-temporary organization of biological systems. Experimental evidence is provided for this concept with emphasis on its theoretical and medical values. A role of spatial and temporary organization in the activity of the biological system is shown separately. It is emphasized that the spatial-temporary organization of biological system is not the sum of properties of components of its spatial and temporary organizations and has its own features. The author proposed to single out a section of theoretical biology dealing with the study of the spatial-temporary organization of biological systems and to call it chronotopobiology.

Aging↗

[Spatial and temporary changes in sensitivity of murine proliferative system and energy exchange to typhoid fever infection].

The authors studied the spatial and temporary organization of the proliferative system and energy exchange in the small intestinal epithelium, as well as spatial and temporary changes in the sensitivity of these systems in mice to typhoid fever infection (cultured Salmonella typhi, 4446) at day and night. The small intestinal epithelial systems were found to show a spatial and time organization and a close correlation between their temporary and spatial changes after infection. The temporary organization of the proliferative system in the esophageal epithelium is more sensitive to infection in the day-time and that of the small intestinal epithelial proliferative system is more marked at night. Thus, these changes are tissue-specific. Typhoid fever infection causes a negative effect on the proliferative system of the small intestine at night and on its energy exchange in the day-time, which shows the system-specific response of the temporary organization of a biological process within the same organ. The changes in the spatial proliferative and energy exchange parameters in the small intestinal epithelium, which have been caused by the infection of animals, depend on the time of a day.

Animals↗

[Gravitation sensitivity of human endothelium].

Experiments on the effects of hypogravity (clinostatting) on growth and formation of monolayer of cultivated endothelium cells of the human umbilical vein demonstrated sensitivity of endothelium to the gravitational stimulus as it responded by a significant reduction of the proliferative activity of cells in culture. The most favorable conditions for cultivating endothelium cells under extended (15-d) hypogravity in vitro were determined.

Adaptation, Physiological↗

[Coculture of human endothelium and smooth muscle cells: functional heterogeneity of endothelial cells from zones with different susceptibility to atherosclerosis].

Using co-culture technique and 3H-thymidine radioautography we have studied effects of human aortic endothelial cells (EC), isolated separately from zones of low (LP) and high (HP) probability of atherosclerosis of grossly normal and atherosclerotic aortas, on 3H-thymidine incorporation by human intimal smooth muscle cells (SMCs). It was found that EC activity depended on a zone of probability, from which the cells were isolated, and on the degree of atherosclerotic lesion. The first-passage ECs from grossly normal LP zones inhibited 3H-thymidine incorporation, compared to control, incubated without Ecs, SMCs (63.5 +/- 27.5%). Cells from HP zones of the same vessels were less active or stimulated SMC proliferation (99.4 +/- 42.9%). EC cultures obtained from both LP and HP zones of atherosclerotic vessels had, as a rule, no effect or increased 3H-thymidine incorporation by SMCs (100.3 +/- 19.8 and 124.1 +/- 20.1%). In contrast to morphologically heterogeneous primary and first-passage cultures obtained from high seeding density, EC monolayers obtained with a split 1:10 were composed predominantly of small mononuclear cells. These cultures effectively inhibited SMC DNA synthesis independently of a zone of probability and a degree of atherosclerotic lesion of aorta (60.4 +/- 10.0 and 51.5 +/- 12.7%). The obtained data suggest that EC morphological heterogeneity is accompanied by functional changes of cells and may be involved in atherosclerotic plaque formation.

Arteriosclerosis↗

[Role of staphylococcus aureus hemolytic toxin-alpha in pathogenesis of infectious endocarditis: studies in vitro].

AIM: To study effects of alpha-toxin (AT) Staphylococcus aureus on human platelets and endothelial cells. MATERIALS AND METHODS: Concentrations of intracellular calcium in human platelets and endothelial cells were estimated by fluorescence, phosphoinositide metabolism in the endothelial cells was studied using 3H-myoinositole. RESULTS: AT induced a dose-dependent increase of intracellular calcium in blood and vascular cells, stimulates dose-dependent formation of inositol phosphates in endothelial cells. CONCLUSION: AT action on the platelets and endothelial cells results in a significant receptor-independent rise in concentration of intracellular calcium, activation of phosphoinositide metabolism, death of cells. These data support the hypothesis that the platelet and endothelial cell damage is mostly due to the passive Ca2+ influxvia pores formed by AT in cellular membrane.

Bacterial Toxins↗

[Induction of cell adhesion molecules, E-selectin, VCAM-1 and ICAM-1, in a co-culture of human endothelial and smooth muscle cells].

Using immunofluorescence and flow cytometry, we studied the surface expression of cell adhesion molecules, E-selectin, VCAM-1 and ICAM-1, in human umbilical vein endothelial cells (HUVEC) co-cultured with human aortic intimal smooth muscle cells (SMC). It was found that inactivated HUVEC constitutively expressed only ICAM-1. After 3-4 h of co-culturing with SMC in the Transwell system we observed the appearance of E-selectin and VCAM-1, and the increase of ICAM-1 content on the cell surface. In all the cases, the maximum expression of these molecules (85-100% of positively stained cells) was detected within 18-24 h after co-culturing. Similar effect was exerted by SMC-conditioned culture medium, whose action well compared with that of a direct addition of interleukin-1 to EC at a concentration of 5-10 u/ml. The obtained data suggest that the cytokines secreted by SMC may participate in the regulation of endothelial cell adhesion molecule expression, and influence cell accumulation in sites of inflammation, immune disorders, etc.

Cell Adhesion Molecules↗

[Morphologic and functional characterization of human aortic endothelium. III. Growth in culture and colony formation at low seeding density].

In human aortic endothelial cell (HAEC) cultures, obtained separately from aortic zones of low (LP) and high (HP) probability of atherosclerosis, proliferative characteristics of cells and HAEC ability to form colonies at clonal seeding density were studied. It has been found that the population doubling time is significantly higher in endothelial cell (EC) cultures from HP-zones, compared to that in cultures from LP-zones of the same vessels. In cultures from both LP- and HP-zones only a few percent of EC had a proliferative potential enough to form cell colonies. The number of formed colonies was always lower in EC cultures from HP-zones, and decreased depending on atherosclerotic lesions and cell donor age. The obtained data suggest that the decline of EC proliferative potential, mostly in HP-zones (even without visible signs of atherosclerotic lesions) is due to a decrease in the number of cells with a high mitotic activity, i.e. "cambial" cells.

Aorta↗

[A chronobiological study of the function of the epithelial proliferative system of the murine esophagus after its infection with typhoid and the use of lomefloxacin].

The rhythmical character of the function of the proliferative system of the oesophagus epithelium of mice changed after infection by Salmonella typhi and after injection of lomefloxacin to intact and infected mice. The degree of the changes depended on the exposure time. The proliferative system of the oesophagus epithelium was more resistant to the infection in the night-time than the day-time and equally resistant to the effect of lomefloxacin in both the day-time and the night-time. The proliferative system of the oesophagus epithelium of the infected mice exposed to lomefloxacin in the day-time proved to be in a noncompensated state and in the night-time it proved to be in the hyperfunctional state.

Animals↗

[The general concepts of development and the principle of sustainable development].

A concept of the sustainable development principle proposed by the United Nations/International Committee on Environment and Development (ICED, 1987) and gained acceptance at the United Nations Conference on Environment and Development (Rio-de-Janeiro, 1992) lies not in the notion of a sustained character of the development but in an understanding of the development as a steadily and long existing and maintained process that is in advocating the stability of the development. It is known, that the state instability of open self-organizing and self-developing systems including the social ones is the the source of the development having a probabilistic, bifurcate and not quite predictable character. Such an understanding of the development should be well represented in the action initiated in the frame work of national and international state ecological policies.

Conservation of Natural Resources↗

[Interaction of a monoclonal antibody to P-selectin with activated platelets and endothelial cells. Heterogeneity of expressing P-selectin in human aorta endothelial cells].

Monoclonal antibody (MAb) CRC81 against P-selectin, a membrane cell adhesion protein of platelets and endothelial cells (EC), has been obtained and characterized. The antibody selectively interacted with the surface of activated platelets and EC due to the redistribution of P-selectin from intracellular organelles onto the surface by activation. MAb CRC81 could recognize not only human but also rabbit and dog P-selectins. MAb CRC81 was used to establish the heterogeneity of human aorta EC with regard to the P-selectin content. Some of the cells in culture did not contain this protein but were nevertheless positively stained for von Willebrand factor, a specific marker for EC which, similar to P-selectin, is localized in Weibel-Palade's bodies. The proportion of P-selectin negative EC increased dramatically in the course of cell passaging: in primary cultures of aortic EC their content was about 15%, while after the 6th passage it exceeded 90%.

Animals↗

[Antiendothelial antibodies in systemic scleroderma and Raynaud's disease].

Using ELISA on fixed endothelial hybridoma (EAhy.926) cells we investigated the occurrence of antiendothelial antibodies (AEA) in the sera from patients with scleroderma systematica (SS) (n = 70) and Raynaud's disease (RD) (n = 19). The mean IgG and IgA-AEA levels were significantly higher in the SS patients than RD patients (p < 0.001) and controls (p < 0.001). We have detected circulating IgG-AEA in 64.2% of patients with SS, 35.2% of SS sera were positive for IgA-AEA. In patients with RD, the frequency of AEA corresponded to that of the random population sample. We have found a high incidence of Raynaud's phenomenon, myositis, telangiectasia and marked digital ischaemia (digital ischemic pulp ulcers, digital scars, osteolysis and autoamputation) among AEA positive patients with SS. AEA-positive patients were characterized by high extent and severity of Raynaud's phenomenon and higher average nailfold capillary microscopy scores. No correlations were found between AEA and different clinical or laboratory parameters, including the type of scleroderma (diffuse and limited), the presence of anti-Scl-7O and anticentromere antibodies and the clinical features of SS (lungs, kidneys and heart involvement, esophageal dysfunction, calcinosis, Sjogren's syndrome). There was no significant correlation between the AEA level and patient age, extent of skin involvement (skin score). Thus, in SS, AEA is associated with a peripheral vasculopathy and represent a useful marker for the diagnosis of endothelial dysfunction.

Adolescent↗

[Temporal organization and information in biological systems].

Analysis of the available chronobiological data leads to the following conclusions about the role of biorhythms in the informational interface in living systems: (1) temporal organization of living systems is the main channel of informational interface in organism (the principle of the bond between information and temporal organization); (2) biorhythms or, more accurately, temporal organization of type one postulates the fulfillment of one of the fundamental statements of the general information theory, i.e., correspondence of information to the substratum of its application (the correspondence principle); (3) the biorhythm phases can either unidirectionally strengthen, weaken or realize in different directions the biological potentials of information brought into organism by one and the same material carrier (the principle of amplification, attenuation or inversion of informational potential by biorhythm); (4) biorhythm is the mechanisms driving the transformation of continuous informational signal, if any, into discrete, i.e. the one apt to fulfil a substantial informational stimulus (the quantification principle); (5) as an oscillating reiterative process responsible for reproduction of a biological phenomenon or a biosystem state within nearly equal periods, biorhythm can be viewed as one of the mechanisms of propagation of information in biosystem (the multiplication principle); (6) reproduction of information through biorhythm is one of the universal mechanisms of information survival in biosystem (the information survival principle); (7) aggregation of biorhythms with different periodicity of the same function, i.e. temporal organization of type two, makes it possible for living system to cover a wide frequency spectrum of perception, transmission and replication of signals carrying bio-information with similar semantics, and to make its differential choice when necessary (the principle of optimality of differential choice in perception, transmission and replication of information); biorhythms of an integral whole (temporal organization) is the mechanism underlying the informational interface between biological time of living system and physical time of its environment (the principle of informational interface between biological and physical time).

Animals↗