Dual wavelength Talbot self-imaging using facet patterned nonlinear crystals.

A method for functional patterning of facets of a nonlinear crystal using focused ion beam milling has been developed. The near-field diffraction on periodic gratings has been experimentally and theoretically studied. The periodicity of the structure enables Talbot self-imaging at the fundamental and second-harmonic frequencies simultaneously. Spatial interference patterns for both harmonic frequencies are individual ones, which can enable the higher-accuracy optical testing, coupling the radiation at both frequencies, and wavelength-division demultiplexing. The impact of the aperture effect on a Talbot carpet is discussed.

[On respiratory protection of workers].

The article deals with employer's requirements regulating choice and management of respirators use in RF. Considerations include drawbacks of these requirements, their inadequacy to contemporary western standards, and evidences that fulfilment of these requirements fails to reduce risk of polluted air effects towards the safety. The authors demonstrate that decreasing jeopardy class with workers' use of respirators according to legal regulations is unallowable. Recommendations are given to improve requirements for workers' protection against air pollution.

Nonlinear Raman-Nath diffraction of femtosecond laser pulses in a 2D nonlinear photonic crystal.

We study second-harmonic generation (SHG) of femtosecond laser pulses in a rectangular two-dimensional nonlinear photonic crystal (NLPC). Multiple SH beams were observed in the vicinity of the propagation direction of the fundamental beam. It has been verified that the angular positions of these beams obey the conditions of nonlinear Raman-Nath diffraction (NRND). The measured SH spectra of specific NRND orders consist of narrow peaks that experience a high-frequency spectral shift as the order grows. We derive an analytical expression for the process studied and find the theoretical results to be in good agreement with the experimental data. We estimate the enhancement factor of nonlinear Raman-Nath diffraction in 2D NLPC to be 70.

[Proper use of gas masks as prevention of occupational diseases].

In the paper there are considered the problems arising from the use of respirators: 1. Modern methods used to replace the gas mask filter, 2. Conditions for safe re-use filters which are not fully developed their service life period 3. The conditions of safe use ofrespiratory protective equipment (RPE) in the immediately dangerous air pollution. Measures for the protection of health, based on the common practice of using RPE in the developed countries, which include: the development and application of regulations governing the selection and the use of respirators, filter replacement, training of staff have been proposed.

[On individual protective means for workers' respiratory organs (review of literature)].

The article covers topics of selecting and organizing the application of individual protective means for respiratory organs in Russian Federation and abroad. The authors reviewed recommendations of the national authors on respirators selection (over last 50 years) and demonstrated the inconsistency with contemporary worldwide practice. Absent legal regulation of respirators selection and of respiratory organs protection programs, lack of training programs and tutorials based on legislation requirements can be potentially harmful for workers' health. The authors therefore suggested ways to lower this potential harm, based on practice of selection and application of respiratory protection systems in foreign countries and on increased control over respirators certification and outdated models replacement.

[Individual devices for protection of the respiratory organs against dust].

The article covers efficiency of individual protective means for respiratory organs in high dust content of workplace air, define ways to increase the efficiency.

[A new approach to the determination of glycogen concentration in various tissues and comments on the interpretation of its results].

A simple specific method for the detection of glycogen concentration in various tissues without disintegration of its structure is described. The method includes staining of glycogen molecules with iodine. The results of determination do not depend on the presence of polysaccharides because they are not stained with iodine but release reducing sugars during hydrolysis. Glycogen content is calculated from the calibration curve.

[Specificity of the lipoproteins metabolism in rats]. / Osobennosti metabolizma lipoproteinov u krys.

The article reviews the data on rat lipoproteins metabolism and points to some principal differences from that in humans. Sixteen such differences are described concerning spectrum of lipoproteins, their quantity and chemical composition, characteristics of biosynthesis and catabolism, absence of the systems of lipid transport between some classes of lipoproteins.

[Blood serum cholesterol and the state of the immune system]. / Kholesterin syvorotki krovi i sostoianie sistemy immuniteta.

This review deals with information on the relationship of the immunity system and the lipid transport system. The data of literature and the results obtained by the authors indicated that an elevated level of cholesterol in the blood serum is associated with the increased activity of the immunity system. On the one hand, lipids and their metabolites produce an immunomodulating effect and, on the other hand, biologically active molecules, synthesized by immunocompetent cells in the process of their activation and proliferation, regulate lipid metabolism.

Effect of bile acids on the proliferative activity and apoptosis of rat hepatocytes.

Bile acids are known to have damaging as well as protective effects on liver cells. A likely candidate for bile acid-mediated hepatocellular injury during cholestasis is glycochenodeoxycholic acid (GCDCA), a hydrophobic bile acid with a direct cytotoxic effect on hepatocytes. In contrast, ursodeoxycholic acid was shown to exhibit protective effects. Our aim was to determine the effect of GCDCA on proliferation, synthesis and secretion of proteins and death processes in cultured rat hepatocytes. Furthermore, it should be studied whether the hydrophilic bile acid tauroursodeoxycholic acid (TUDCA) might be able to protect cells from the damaging effect of GCDCA. Our results demonstrate that GCDCA decreased dose-dependently hepatocellular proliferation, synthesis and secretion of newly synthesized proteins and, at low concentration, induced apoptosis or, at high doses, cytolysis of cultured hepatocytes. TUDCA did not exert cytotoxic effects on the isolated hepatocytes at a wide range of concentrations. However, TUDCA coincubated with GCDCA protected the cells from the damaging effect of GCDCA at all measured parameters except the secretion of newly synthesized protein.

Antiatherogenic effects of 17 beta-estradiol and 17 alpha-estradiol and its derivative J811 in cholesterol-fed rabbits with thyroid inhibition.

OBJECTIVE: The aim of this study was to investigate the antiatherogenic effects of 17 beta-estradiol and 17 alpha-estradiol and its derivative J811 (estra-1,3,5(10),8-tetraene-3, 17 alpha-diol), having a non-feminizing effect and high antioxidant potential, in male rabbits. EXPERIMENTAL DESIGN: Male White-Russian rabbits weighing 2.1-2.6 kg were fed either a standard or a high-cholesterol (200 mg/kg) diet, with thyroid function-inhibiting thiouracil (20 mg/kg) combined with cholic acid (40 mg/kg) administered daily in sunflower oil for 3 months. During the last month of the study, estrogens were administered by gavage at a dose of 0.02 or 0.1 mg/kg. RESULTS AND CONCLUSIONS: All three estrogens exerted remarkable antiatherosclerotic effects. Decreases in serum and aortic-wall lipid parameters and the index of atherogenicity were dependent on estrogen dose. Morphological evaluation of the aortic wall (height of plaques, size of plaque relative to aortic half-circumference) showed only weak therapeutic effects with all three estrogens. It is an open question whether the treatment period was too short to reverse the above changes. On the other hand, the data clearly suggest that 17 alpha-estradiol and J811 offer new perspectives for the prevention of atherosclerosis in men, which is similar to that found with 17 beta-estradiol in women.

[The role of biochemical study of the saliva in diagnosing diseases]. / Rol' biokhimicheskogo issledovaniia sliuny v diagnostike zabolevanii.

Mixed saliva contains numerous biological molecules which participate in regulation of the functions of the major physiological systems or are products of their work. Therefore, salivary components reflect the status of body systems and can provide diagnostic information about their abnormalities.

Effect of polyunsaturated phosphatidyl-choline on lipid transport system in alcoholic liver injury.

The aim of this study was to determine whether serum lipid composition and lipolytic activities in alcoholinduced liver dystrophy were modified by the co-administration of polyunsaturated phosphatidylcholine (PPC). Chronic alcohol intoxication was induced in rats by intragastric ethanol administration of 3.5 g/kg body weight per day over 56 days. Aqueous PPC suspension was given intragastrally in doses of 100 and 300 mg/kg body weight. Chronic alcohol intoxication led to the development of protein and lipid dystrophy of hepatocytes. PPC partially prevented alcoholic injury of the liver cells and had a normalizing effect on cholesterol esterification, lipolysis of lipoproteins and on the fatty acid composition of the main lipoprotein classes.

[The radioprotective properties of a lipocarotenoid extract of Rhodotorula glutinis yeasts]. / Protivoluchevye svoistva lipokarotinoidnogo ékstrakta iz drozhzhei Rhodotorula glutinis.

The dynamics of formation of lipids and carotinoids by the Rh. glutinis yeast and the influence of the culture's age on the composition of the product were studied. The composition of a lipocarotinoid complex isolated from the yeast (at a stage of its stationary growth) was determined. It was shown that this complex lipocarotinoid preparation produces a normalizing effect on the parameters of the lipid-transport system and peroxide oxidation of blood serum lipids of irradiated rats.

[Effect of polyunsaturated phosphatidylcholine on the activity of antioxidant and lipolytic enzymes in alimentary hypercholesterolemia in irradiated rats]. / Deistvie polinenasyshchennogo fosfatidylkholina na aktivnost' antioksidantnykh i lipoliticheskikh fermentov pri alimentarnoi giperkholesterinemii u obluchennykh krys.

A high-cholesterol diet containing 3.5% cholesterol, 0.2% methyl thiouracil and 20% of heated sunflower-seed oil caused an increase in the content of cholesterol, triacylglycerols, diene conjugates and in the activity of phospholipase A2 in rat liver and of serum total cholesterol and cholesterol of low density lipoproteins, and a decrease in the activity of hepatic cholesterol esterase, in the fractional activity of lecithin:cholesterol acetyl transferase (LCAT), in the activity of the enzymes involved in the lipolytic transformation of lipoproteins and in the serum levels of very low density lipoprotein cholesterol. The content of malonic dialdehyde in liver tissue and molar activity of LCAT in blood serum were increased after preirradiation (0.5 and 5.0 Gy) of rats kept on the cholesterol diet. The preparation of polyunsaturated phosphatidylcholine was shown to decrease the content of triacylglycerols and diene conjugates in liver tissue of rats with alimentary hypercholesterolemia. In rats irradiated in a dose of 0.5 Gy the phosphatidylcholine preparation decreased the content of cholesterol in liver tissue and blood serum, exhibited the normalizing effect on the content of cholesterol of high density lipoproteins, on the activity of superoxide dismutase and glutathione peroxidase; in a dose of 5.0 Gy this phosphatidylcholine preparation normalized the content of malonic dialdehyde, activity of the enzymes involved in lipolytic transformation of lipoproteins and increased the LCAT activity.

[Differential forms of self-directed study of biochemistry in medical schools]. / Differentsirovannye formy samostoiatel'noi raboty studentov pri izuchenii biokhimii v meditsinskom vuze.

Methods of self-directed study of biochemistry by students are considered in connection with initial levels of their theoretical knowledge and laboratory experience. This type of training involved individual tasks and free discussion on the results obtained. Optimal results were observed in organization of self-directed work in small groups.

[Status of the pituitary-adrenal system and biogenic amine levels after extensive resection of the intestines]. / Sostoianie gipofizarno-adrenalovoi sistemy i soderzhanie biogennykh aminov posle obshirnykh rezektsii kishechnika.

A clinico-experimental investigations for the determination of contents of serotonin, histamine, 11-OCS and ACTH in blood as well as excretion of adrenaline and noradrenaline after extensive resection of the intestine are described. It was shown that the dynamics of contents of biologically active substances in the blood depended on the level of resection and terms after operation. Extensive resection of the intestine is followed by inhibition of the sympatho-adrenal system resulting in reduction of noradrenaline in blood and its excretion with increased excretion of adrenaline.

[The characteristics of the lecithin-cholesterol-acyltransferase reaction in the blood serum during liver regeneration]. / Kharakteristika letsitin-kholesterol-atsiltransferaznoi reaktsii v syvorotke krovi pri regeneratsii pecheni.

The rate of cholesterin ether formation in blood serum during the periods of rapid recovery of liver mass decreases after partial hepatectomy in rats. This effect is connected with the changes in quantity and composition of lecithin cholesterin acyltransferase (LCAT) as well the kinetic characteristics of lipoprotein of high density. This ferment was isolated from blood serum and purified in 28,500 times at different periods of liver regeneration. A conclusion concerning the presence of reverse dependence between the pronounced regeneration processes in liver and LCAT activity at high level of nonetherificated cholesterin in substrate has been drawn. Some recommendations for LCAT activity reducing processes in liver are given.