Effect of compounds with anxiolytic properties on voluntary ethanol consumption by rats

The effect of different chemical anxiolytic agents on ethanol consumption has been studied on the model of experimental alcoholism in rats. The decrease of ethanol consumption was dose-dependent. The existence of non-benzodiazepine anxiolytic systems is suggested.     

Aggregates of modified low density lipoproteins indicate accumulation of lipids in human aortic intima cells in vitro

Spontaneous aggregation of glycosylated, desialated, oxidized and malondialdehyde modified low density lipoprotein (LDL) as well as LDL of coronary heart disease patients has been discovered using methods for determination of light transmission fluctuations in suspensions and gel filtration. At the same time; LDL of healthy donors failed to aggregate under conditions of cellular culture. On the other hand, human aortic cells from unaffected intima incubated with modified LDL, but not native LDL of healthy donors, showed a rise in esterified cholesterol levels. There was a strong correlation between the degree of LDL aggregation and intracellular cholesterol ester accumulation (r-0.86, p 0.001, n-21). Removal of aggregates by passing preparations through and 0.1 um filter significantly inhibited the accumulation of cholesterol esters. The obtained data point to the essential, if not decisive, role of LDL aggregation in the processes of lipid accumulation by intimal cells in vitro.     

Association of low-density lipoprotein with particulate connective tissue matrix components enhances cholesterol accumulation in cultured subendothelial cells of human aorta

Low-density lipoproteins (LDL) were incubated with elastin particles, collagenase-resistant debris isolated from human aorta, and latex beads of 1.13 microns in diameter. As a result of incubation, insoluble LDL-associates were formed. These associates, as well as LDL-heparin-fibronectin-gelatin complexes described by other workers, were added to a 7-day primary culture of enzyme-isolated cells of human aortic subendothelial intima. The culture contained a mixed cell population made up mostly of typical and modified smooth muscle cells. 24 h later, total cholesterol, phospholipid, triacylglycerol, free cholesterol and cholesteryl ester levels were measured. Addition of insoluble LDL-complexes as well as LDL-associates to culture brought about a substantial accumulation of intracellular lipids; primarily, cholesteryl esters. The total cholesterol level in cultured cells was raised 3- to 8-fold. Addition of free LDL or LDL-free particles had no effect on the content of intracellular lipids. The results obtained allow the assumption that the occurrence of the LDL-mediated accumulation of intracellular lipids is due mainly to the LDL penetration inside the cell via 'nonspecific' phagocytosis and not through a regulated receptor-dependent pathway.     

Molecular cloning of tylosin-producing Streptomyces fradiae B-45 genes determining increased inducible resistance to tylosin in Streptomyces lividans TK64

DNA of S. fradiae B-45 partially cleaved by Sau3A restrictase was cloned in S. lividans TK64 in the plasmid vector pIJ702. Three recombinant plasmids pVG251, pVG262, and pVG253 with tlr1, tlr2 and tlr3 genes were isolated from the transformed clones of S. lividans TK64 with higher inducible resistance to tylosin as compared to the plasmid-free strain. DNA-DNA blot hybridization was performed between the total DNA cleaved by several restrictases from S. fradiae B-45 and some other strains and the DNA probes containing the tlr genes. It was shown that tlr1 and tlr3 genes were unique in S. fradiae B-45. Sequences homologous to tlr2 gene were present both in DNA of S. fradiae B-45 in 7 copies and in strains of S. antibiotics and S. hygroscopicus producing respectively oleandomycin and turimycin.     

Study of the structural and functional properties of fibronectin--a high molecular weight plasma glycoproteins--by using monoclonal antibodies

Functional and structural properties of fibronectin--high molecular weight glyco-protein from human plasma--were studied by monoclonal antibodies against fibronectin. It was shown that monoclonal antibodies against human plasma fibronectin exhibit a certain species specificity. Antigenic determinant for our monoclonal antibody is located in the central part of the protein polypeptide chain--in the structural domain. The monoclonal antibodies studied do not inhibit any tested functions of fibronectin. In contrast, polyclonal antibodies are not species specific and inhibit all fibronectin functions.     

Similarity Between Naturally Occurring Modified Desialylated, Electronegative and Aortic Low Density Lipoprotein

The sialic acid content of electronegative low density lipoprotein (LDL) and LDL isolated from human aortic intima was measured. Sialic acid level in electronegative LDL of healthy subjects was 1.7-fold lower than in native LDL. Sialic acid content in electronegative LDL of coronary atherosclerosis patients was 3-fold lower than in native LDL. Lipoproteins isolated from grossly normal human aortic intima and from fatty streaks contained 20-56% less sialic acid as compared to blood plasma LDL. A negative correlation was established between the ability of electronegative and aortic LDL to stimulate lipid accumulation in cells cultured from uninvolved human aortic intima and lipoprotein sialic acid content. The results obtained indicate that electronegative and aortic LDLs have a low sialic acid content, i.e., are desialylated lipoproteins. Considered together with the fact that all known atherogenic LDLs have similar characteristics, our findings suggest that modified LDLs are the same lipoprotein particles subjected to multiple modification.     

An estimate of spin diffusion in a spin subset: Application to iterative distance calculation from 3D 15N NOESY-HMQC

Summary A method for quantification of distances between amide hydrogens using only the 3D NOESY-HMQC experiment recorded on a ¹⁵N-labelled protein is presented. This method is based on an approximate expression of the NOE intensities between amide hydrogens obtained from continuum modelling of the non-amide spins; this expression is used in a distance calculation algorithm. The algorithm has been named CROWD, standing for Continuum approximation of Relaxati On path Ways between Dilute spins. This approximation as well as the CROWD algorithm are tested on a simulated case; the CROWD algorithm is then applied to experimental data, measured on a fragment of bacteriorhodopsin.     

Stellate cells of aortic intima: I. Human and rabbit.

Stellate cells hitherto accounted exclusively in the innermost elastic-hyperplastic layer were already reported to inhabit human aortic intima. The present paper shows that most of these cells are situated just beneath the endothelium. Stellate cells also appear in the deendothelialization-induced myointimal thickening of rabbit aorta. In the myointimal thickening these cells were revealed in the direct proximity to the endothelium. A conclusion is available that the previously demonstrated polymorphism of human aortic intimal cells may be reproduced in a simple experimental model, which gives new possibilities for the study of the cellular polymorphism in the vessel wall.     

Stellate cells of aortic intima: II. Arborization of intimal cells in culture.

The present study analyzed effects of different cAMP-elevators on cell morphology in primary culture of human intimal and medial cells from grossly normal and atherosclerotic areas. In primary culture of human aortic cells adenylate cyclase activator forskolin and other cAMP elevators induced arborization of cells, i.e. they reversibly changed the shape of cells. This resulted in the formation of thin branching processes and in the concentration of cytoplasm around the nucleus. In the culture, the shape of the arborized cells resembled that of stellate ones detected in the aortic intima in situ. The arborization of cells was accompanied by destruction of myofilaments. Due to cAMP elevators' effect, most of the arborized cells were exhibited in the cultures isolated from the elastic-hyperplastic layer of the intima. The number of arborized cells was significantly less in the cultures isolated from the musculo-elastic layer and still lesser in those isolated from media. We failed to reveal any significant difference in the number of arborized cells cultured from fatty streaks, atherosclerotic plaques and grossly normal aortic areas. Obtained results suggest that the previously revealed polymorphism of human aortic intimal cells may be accounted for by the cell shape transformations underlined by the mechanism similar to that of arborization in vitro.     

Quantitative estimation of lipid-laden cells in atherosclerotic lesions of the human aorta.

The intima of the adult human aorta consists of three sublayers: a muscular layer lying next to the media, a median hyperplastic layer and an innermost connective tissue layer, adjoining the lumen. The cells inhabiting these sublayers were isolated by the method of alcoholic-alkaline dissociation from grossly normal areas, fatty streaks and atherosclerotic plaques. The populations obtained contained cells with different numbers of cytoplasmic inclusions and a number without any. In unaffected intima and in fatty streaks, the cells with lipid inclusions were found predominantly in the outermost intimal layer including the connective tissue and in part of the median hyperplastic layer. In the superficial layer of unaffected intima and the fatty streak, these cells accounted for 15 and 25% of the total cell population, respectively. In the plaque, most cells with lipid inclusions were localized in the median hyperplastic layer of the intima (10%). The muscular layer was characterized by the lowest content of cells with lipid inclusions both in the unaffected intima and atherosclerotic lesions (from 0.75% in unaffected intima to 5% plaques). Among the intimal smooth muscle cells of various shapes, the cells with lipid inclusions were most often found in the stellate cell subpopulation (5-35%). A possible role of stellate cells in atherogenesis is discussed.