PubMed HealthSearch

Biomedical subjects

Iu A Romanov

Publications and source records attributed to Iu A Romanov.

At least 19 recordsLinked to original sources

[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

[Chronobiological patterns in the course of amphibian metamorphosis].

Metamorphic rates in Rana temporaria larvae treated with thyroxine and prolactin were observed in different phases of the light-dark cycle. Different hormonal effects on tadpole development were demonstrated depending on the light-dark phases. Thyroxine always accelerated the development. Thyroxine employed at L-D and D-L phases was more effective than in T and D phases. Prolactin retarded metamorphosis in D phase and accelerated in L-D phase. This work demonstrated some temporal relief of hormonal sensitivity of anuran metamorphosis.

Amphibians

[Signal-conducting and low molecular weight GTP-binding proteins from the lung and endothelium: localization in membranes and cytosol, interaction with F-actin].

The following proteins have been identified in mammalian lung and endothelium, using [32P]ADP-ribosylation by bacterial ADP-ribosyltransferase, immuno- and [alpha-32P]GTP-blottings: 41 kDa Gi1 alpha, 40 kDa Gi2 alpha, 41 kDa Gi3 alpha, 40 kDa and 45 kDa subunits of GS alpha, 36 kDa beta 1 and 35 kDa beta 2 subunits of signal-transmitting GTP-binding proteins (G-proteins), the 19-26 kDa low molecular weight GTP-binding proteins (SMG-proteins) ras, rho, rac, G25K (Gp), as well as ARF and SMG proteins binding with a high affinity to [alpha-32P]GTP. These G- and SMG-proteins are contained in various proportions in membrane and cytosol fractions of lung and endothelium cells. Subunits Gi2 alpha and GS alpha (but not beta 1 or SMG-proteins) my partially (approximately 1%) dissociate from the membrane by the action of the GTP analogs GTP[S] or Gpp(NH)p in the presence of magnesium ions. Extraction with low ionic strength buffer solutions in the presence of EDTA is accompanied by the release of G-actin sensitive to whooping cough toxin Gi2 alpha and beta i subunits. The functionally coupled into a alpha beta gamma heterodimer Gi-protein subunits (predominantly Gi2 alpha and beta i) present in the cytosol fraction as well as the SMG-proteins revealed by [alpha-32P]GTP-blotting (but not the SMG-proteins sensitive to the botulinic C3 exoenzyme, rho/rac, or ARF, may interact with F-actin. Approximately 20% of these proteins are associated with the Triton X-100 insoluble (cytoskeletal) fraction of the endothelium. A conclusion is drawn that interactions of G- and SMG-proteins with actin filaments may be the reason for the formation of "multidisperse" structure in a cell.

Actins

[Changes in the level of DNA synthesis in a culture of Ehrlich ascites tumor cells under the action of different concentrations of a chalone-containing preparation].

The study was made of the effect of various concentrations of chalone-containing preparation from ascitic Ehrlich tumor on DNA synthesis in the tumor. The preparation was shown to suppress DNA synthesis in dose-dependent manner. The dose dependence was characterized by the effect of saturation which is likely to reflect binding of chalone molecules with specific cell receptors.

Animals

[Effects of phytoadaptogens on biorhythms of indicators of the hemostasis system in dogs].

Circadian rhythms in dog hemostasis were studied in winter. The animals were fed with eleutherococcus and liquorice extracts with bread in different time of the day. Hemostatic investigations revealed chronosensitivity of hemostasis to the phytoadaptogens which is important for assessment of their chronopharmacological properties and prospects of their use.

Adaptation, Physiological

[The morphological and functional characteristics of human aortic endothelium. II. Cellular polymorphism and the incorporation of 3H-thymidine in a culture].

The content of multinuclear endothelial cells and the ability of cells to incorporate 3H-thymidine were studied in primary cultures isolated from zones of low (LP) and high (HP) probability of atherosclerosis of adult human aortas. It was found that the percentage of multinuclear EC was at mean 2-fold higher in cultures from HP zones compared to LP zones of the same vessels. In primary cultures and in the first passage cultures only small mononuclear EC were able to incorporate 3H-thymidine. A significant decrease in the thymidine index (TI) was found only in cultures from HP zones of atherosclerotic aortas. In cultures of EC from the LP zones of these aortas the TI was as high as in cultures from the LP and HP zones from grossly normal vessels.

Aorta

[Effects of propranolol on mitosis-inhibiting activity of G2-chalone and adrenaline in cell culture of Ehrlich's ascites tumor].

Chalone-containing preparation from ascite Ehrlich's tumour blocks these cell transition from G2-phase to mitosis and its motion in mitosis in vitro (G2-block, M-block). Adrenaline blocks these cell transition from G2-phase to mitosis. Propranolol raises G2-block of chalone or adrenaline. Consequently this way of chalones action on cell division includes beta-adrenergic receptors influence of preparation on cell motion in mitosis doesn't change with addition of propranolol. Consequently this way of chalone system action on mitosis doesn't include beta-adrenergic receptors.

Animals

[The morphological and functional characteristics of the human aortic endothelium. I. 2 variants of the organization of the endothelial monolayer in atherosclerosis].

The en face organization of human aortic endothelium in zones of low (LP) and high (HP) probability of sudanophilia was examined in preparation impregnated with silver nitrate. It is found that the heterogeneity of endothelial cells (EC) by area is "random" or "clusterized". In the latter case the major part of small and medium-sized EC (less than 800 microns 2) is associated in distinct groups ("clusters") and form foci with high monolayer density. The luminal surface outside the clusters was formed by preferentially large and giant EC. Clusterized endothelium was found with statistically significant higher frequency in HP zones of both "normal" and "atherosclerotic" vessels. The maximum clusterization of EC was revealed on the shoulder region and on the periphery of atherosclerotic plaques which was speculated to be a growth zone of the lesion. It is suggested that the appearance of clusterized endothelium is associated with the active development of atherosclerosis.

Aging

[Fractionation of a chalone-containing substance from Ehrlich's ascites tumor using high pressure chromatography].

The effect of various fractions of chalone--containing preparation from ascyte Ehrlich's tumour obtained by high performance liquid chromatography (HPLC) on mitotic activity and DNA synthesis in the tumour has been studied. After filtration the division of active chalone component which inhibits entering cells into M-phase and S-phase took place. The component inhibiting DNA synthesis eluated with G1-chalone.

Animals

[Use of chemiluminescence analysis in the determination of the activity of hepatic antichalone and chalone].

Partially purified antichalone and chalone from the liver of the mammals possess significant antiradical activity revealed by the chemiluminiscent analysis in the system capable of generating free radicals. Chemiluminiscent damping degree is proportional to the quantity of antichalone and chalone in the system. During the first three days the activity of antichalone is increased, while that of chalone in decreased in the liver of partially hepatectomized rats. In 14 days after partial hepatectomy the activity of both antichalone and chalone decreased, but their ratio is normalized. Thus, the regeneration of the liver in different periods after the operation takes place when the condition of antichalone/chalone system in the organ is unequal.

Animals

[Space-time organization of cellular systems in the normal and pathologic states].

The time-space organization of biological systems, cell systems in particular, is one of the most important problems of current theoretical biology having medical implications. The presented view of the general structure of the temporal organization of biosystems and their development in the course of life evolution interprets the temporal organization of a living system as a complex of regular changes in time, the biological rhythms included, its structures and functions which are interactive and show relationships with cyclic alterations of environmental conditions. A special organization is composed of a group of different structures and related functions which are arranged according to a certain pattern in the space occupied by the biological system and interact with each other. The experimental evidence obtained in studies of the proliferative and metabolic systems of the liver, testify to the existence of a general time-space organization in the cell systems. This organization represents an entity formed by the cellular temporal and special organizations and maintained by relationships and interactions between them.

Animals

[Chronobiological analysis of thyroxine action on cell proliferation in the hypotetraploid strain of Ehrlich's ascitic tumor].

Experiments on white random-bred male mice were made to study the effect of L-thyroxine on cell proliferation of the hypotetraploid strain of Ehrlich's ascites carcinoma. It was shown that prolonged thyroxine administration (during 6 days of carcinoma growth) lead to synchronization of cell proliferation and the maximum values of the mitotic index was found 3 hours earlier then in the control experiments. At the same time thyroxine did not exert any noticeable effect on the average daily magnitudes of the number of DNA-synthesizing cells and did not change the pattern of modulations in the radioactive index. The changes in the mitotic index and radioactive index were asynchronous in control and experimental animals. Analogous results were found for hyperdiploid strain of Ehrlich's ascites tumor. Ploidy of cells did not influence the tipe rhythms of the cell proliferation and its reaction on the action of thyroxine.

Animals