[Comparative Computational Modeling of Agonist Binding to the Leukotriene Receptors BLT1 and BLT2].

The leukotriene B4 receptors BLT1 and BLT2 are promising targets for the treatment of allergic and inflammatory diseases. However, no working model of ligand binding to either of these receptors has been developed so far. Under the assumption that homologous receptors bind their ligands in a similar way, computational modeling of agonist binding to BLT1 and BLT2 was performed using fully flexible docking in Galaxy 7TM. For both receptors, the carboxyl group of the ligand forms a salt bridge with an arginine residue, while the tail hydroxyl groups form hydrogen bonds with three amino acid residues. The differential specificity of ligands to BLT1 and BLT2 is explained by the replacement of histidine with tyrosine. In BLT1, the histidine residue binds the 5-OH group of the ligand, while the tyrosine residue in BLT2 repels it. The presented models are in agreement with experimental data and may be useful for developing new BLT1- and BLT2-targeted drugs.

[Infra-red spectrometry in oral liquid study for diagnostic purposes].

Infra-red (IR) spectrometry of the saliva was done by means of specially developed hardware-software complex. It was established, that in 9 wide ranges of the IR-spectrum there were diverse fluctuations of transmittance that characterize intermolecular interactions of various molecules associated with water and metabolites of biological systems. The found fluctuations were characterized quantitatively by dispersion of transmittance coefficients. It gave chance on 9 values of the given values by means of multidimensional analysis (Mahalanobis distance and Bartlett's criteria) defined on various frequencies of spectrum in comparison with the standard, quantitatively characterize the state of biological liquid that can be used 4 diagnostic purposes.

[Changes in phosphatidylinositol content in patients with myocardial infarct]. / Issledovanie dinamiki soderzhaniia fosfatidilinozita u bol'nykh s infarktom miokarda.

The changes of phosphatidylinositol content in blood of patients with myocardial infarction was studied. A procedure is developed for multiple estimation of phosphatidylinositol content within short-time intervals which enabled one to obtain additional data on the functional state of biomembranes. In the clinical practice the data obtained may be used for diagnosis and evaluation of efficiency of ischemic heart disease treatment.

[The dynamic change in the content of total lipids in myocardial infarct patients]. / Dinamika izmeneniia soderzhaniia obshchikh lipidov u bol'nykh infarktom miokarda.

The dynamics of the content of total lipids (cholesterol and cholesterol esters) was studied in patients with acute large-focal uncomplicated myocardial infarction in different disease periods. Rapid quantitative changes that occur in the content of cholesterol and its esters in the test groups were established to be characterized by marked specificity and by the form of its own in different disease periods (in the acute period--days 2-5 and on day 15--the health status stabilization). It is advisable that the characteristics of the dynamics of rapid reversible changes in the content of total lipids may be used for estimating the status gravity of patients with uncomplicated large-focal myocardial infarction.

[Changes in the level of tightly-bound mitochondrial phospholipids induced by exogenous factors]. / Izmenenie soderzhaniia prochnosviazannykh fosfolipidov mitokhondrii pod vliianiem ékzogennykh faktorov.

The effects of some parameters of the incubation medium (tonicity, H+ and Pi concentration) on the phospholipid content in rat mitochondrial extracts prepared by normal extraction and by extraction with strongly acidified solvent mixtures, were studied. It was found that after normal extraction with a chloroform-methanol mixture, 8% to 25% of mitochondrial phospholipids can be additionally extracted by acidified solvent mixtures. The concentration of weakly extractable lipids depends on the tonicity and ionic composition of the incubation medium. It was suggested that there exist in mitochondria two lipid pools, a loosely and a tightly-bound ones; the equilibrium between these pools is effectively regulated by medium tonicity and other external factors.

[The dynamics of the blood level of phosphatidylinositol in patients with myocardial infarction]. / Dinamika soderzhaniia v krovi fosfatidilinozita u bol'nykh infarktom miokarda.

Phospholipids, particularly inositol-containing ones, that serve as secondary messengers and bioregulators of fundamental biochemical processes, essentially contribute to the origination of cardiovascular diseases. These compounds are highly labile and the data on their levels in the blood and its components in various cardiovascular conditions are contradictory. This may be explained by the fact that phosphatidylinositol levels change immediately after blood collection. Therefore the authors found it interesting to investigate the time course of this phospholipid levels, that may to a certain measure reflect the pattern of the metabolic disorders present in this case. They suggest a method of multiple measurements of phosphatidylinositol levels, carried out in short intervals, this yielding additional data on the function of biologic membranes, that may be useful in the diagnosis of coronary disease and assessment of the efficacy of treatment of this condition.