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Hepoxilin A3-methyl ester is taken up by intact human neutrophils where it is first hydrolyzed into the free acid which is subsequently converted into a single major metabolite. The structure of this metabolite was determined through mass spectral analysis of several derivatives, and through identity with an authentic compound prepared by chemical synthesis. The metabolite was identified as omega-hydroxy-hepoxilin A3 showing that the epoxide functionality of the parent hepoxilin is not opened during incubation with human neutrophils. All attempts to investigate hepoxilin metabolism in broken cells, despite the presence of protease inhibitors (Aproteinin, PMSF, DFP) and supplementation with NADPH were unsuccessful. Metabolism of hepoxilin A3 required the intact cell, while parallel experiments with LTB4 as substrate demonstrated that this eicosanoid was metabolized into its omega-hydroxy metabolite regardless of whether intact or broken cell preparations were used provided that NADPH was present in the latter. Hepoxilin metabolism in intact cells was inhibited dose-dependently by CCCP (0.01-100 microM), a mitochondrial uncoupler, whereas LTB4 metabolism was unaffected by CCCP. This data suggests that metabolism of hepoxilin A3 occurs in intact human neutrophils through omega-oxidation, is likely located in the mitochondrial compartment of the cell (inhibition by CCCP) and is carried out by an activity that is independent of the well characterized, relatively stable microsomal LTB4 omega-hydroxylase.

Background There are few studies of injury rates in Russia9s Volleyball Championship. Objective To investigate incidence and characteristics of injuries in one male volleyball team. Design Prospective cohort pilot study, 2009–2010 (preseason and the competitive season). Setting Professional athletes of elite male division of Russia9s Championship (Super League). Participants 16 players had been taking part in preparation and competitions from 23 June 2009 to 15 May 2010 as The ‘Lokomotiv-Belogorie’ volleyball team. Interventions Volleyball exposure during training and matches was recorded by the coach. The team physician recorded all injuries which had occurred. The incidence of injury was expressed as number of injuries per 1000 player hours. Results 105 injuries were recorded, 22 (20.95%) resulted in one or more days of missed practice or competition. The overall incidence of time-loss injuries was estimated as 2.37 per 1000 player hours. The game incidence was 10.7 and the practice incidence was 1.84. Majority of injuries (86.36%) had slight or minor severity. The most common location of time-loss injuries was the ankle/foot (32.82%), followed by the spine/back (27.27%) and shoulder (13.63%). The most common types were sprain (22.73%) and overuse injuries (63.64%). Many slight and overuse injuries did not cause player to stop playing (only 32.6% of the acute and 11.86% of the overuse were time-loss injuries). Among all registered injuries the prevalence locations were spine/back (22 cases or 21.95%), shoulder (21 cases or 20%) and knee (18 cases or 17.14%) and 71.43% were overuse and 28.57% traumatic. Conclusions The study revealed a high injury incidence rate in games compared to practice. The majority of injuries were overuse injuries. Slight and minor injuries often occurred and most of them were not time-loss. Future investigations are required.

The effects of two acyclic derivatives of arachidonic acid which are formed under the action of 5- and 12-lipoxygenases 5(S)-hydroxy-(6,8Z,11Z,14Z)-eicosatetraenoic acid (5-HETE) and (8R/S)-hydroxy-(11S,12S)-epoxy-5Z,9E,14Z-eicosatrienoi c acid (hepoxilin A3) on extinction of inward current evoked by local acetylcholine (ACh-current) application on soma of Helix lucorum RPa3 and LPa3 neurons were studied by the double-electrode voltage clamp technique. It was shown an increase in ACh-current extinction by 5-HETE. Hepoxilin A3 did not influence cholinoreceptor plasticity. The present results confirm earlier assumptions concerning the regulation of cholinoreceptor plasticity by acyclic eicosanoids which were formed from arachidonic acid under the influence of 5-lipoxygenase and the lack of 12-lipoxygenase metabolites in this regulation.

Acetylenic fatty acids, 8,11,14-eicosatrienoic, 5,8,11,14-eicosatetraenoic and 5,8,11,14,17-eicosapentaenoic acids, were compared with respect to their effects on the particulate prostaglandin H synthase. All the acetylenic acids inactivated the enzyme in a time-dependent manner. The eicosatriynoic and eicosatetraynoic acids exhibited comparable efficacies, whereas the eicosapentaenoic acid proved to be a weaker inactivator. The time-courses of inactivation fitted a kinetic model suggest an enzyme-catalysed conversion of the compounds via alternative suicidal and non-suicidal routes. The characteristics of inactivation of prostaglandin H synthase differ from those of lipoxygenases.

The impact of a non-cyclized arachidonic acid derivative 15S-hydroxy-5Z, 8Z, 11Z, 13E-eicosatetraenoic acid (15-HETE) upon the dynamics of the inward current extinction, caused by repeated ion-tophoretic acetylcholine applications on the soma, was studied through a double electrode voltage clamp technique on the Helix lucorum identified neurons RPa3 and LPa3. The extracellular effect of 15-HETE (4-16 microM) was found to have a two phase influence on the inward current extinction, depending on the time of exposure to the compound. The short-latent effect (up to 60-80 min) displays itself as an extinction decrease, whereas the long-latent effect (after 60-80 min) - as an enhanced extinction. The effects caused by 15-HETE are irreversible. The short-latent one was probably due to the earlier described inhibition of 5- and 12-lipoxygenase enzymes by 15-HETE while the long-latent one - due to its intrinsic function.

The review deals with the basic features of the fatty acid lipoxygenation resulting in the formation of leukotrienes, hydroxy fatty acids, lipoxins, hepoxylins. The biological role, prospects for the further studies of this class of bioregulators are discussed.

The synthesis of 20-azido(tri-n-butyltin)benzoate of 20-hydroxy-(8S)-hepoxilin A3 (HxA3*) methyl ester, a tool for the labelling of proteins involved in hepoxilin metabolism, has been performed starting from a synthetic precursor of 20-hydroxy hepoxilins.

In the summer of 1983, G. A. Sobolev and V. M. Demin of the U.S.S.R. came to Canada to demonstrate techniques using piezoelectrical and other mechanoelectrical effects for in‐mine geophysical surveys. We performed field trials using Soviet and Canadian equipment in the Giant Yellowknife Mine, N. W. T., and the Sullivan Mine, Kimberley, B.C., Canada. The principle of the technique involves detonating an explosive charge and subsequently measuring the strength and delay time of electromagnetic fields generated by excited minerals. Ore grade gold zones at the Giant Yellowknife Mine occur within large quartz lenses in a shear zone in Archean volcanics. Our tests there produced strong signals in the 8 kHz range, which were very similar to piezoelectrical signals produced by quartz samples, in the laboratory at the University of British Columbia. The Sullivan orebody is a 160 million ton iron‐lead‐zinc sulfide deposit lying comformably in Proterozoic rock. Our tests there yielded some very strong electromagnetic signals with frequencies as high as 350 kHz. The short delay times of these signals preclude any possibility that the signals were simple seismic phenomena generated at the antenna sites. Sobolev et al., (1982a, b) suggest that such high‐frequency signals are produced by a highly nonlinear discharge phenomenon occurring at the grain boundaries of naturally occurring semiconductors such as galena, sphalerite, and pyrrhotite.

Using the linear isotropic elasticity-theory approximation, an analysis is made of the splitting of linear superdislocations with an arbitrary Burgers vector near plane interfaces of different types as defined by Head [4].

An alternative technology of benzene alkylation with propylene is proposed at OJSC Omsk rubber. The effectiveness of aluminum chloride catalyst replacement is evaluated on sulfocationites. A discrete supply of propane-propylene fraction to the alkylation reactor is proposed. The mathematical model of benzene alkylation process with propylene using the sulfocationites catalysts was developed. Mathematical model of the process was developed in the program environment AspenTech. The numerical values of the rate constants were determined. An adequate process model allow carrying out numerical experiments on the variation of the basic reagents relations reactions.

Fluroescent spectra of six b-type ferredoxins of plant and animal origins were obtained. All investigated proteins do not contain tryptophan. The emission maxima of the native proteins, apoproteins prepared by various methods, and denaturated proteins are compared. The effects of pH, ionic strength and ferricyanide on the ferredoxins fluorescence were studied. "Unusual" emission at 340nm noted previously for adrenal ferredoxin was observed for spinach and Chenopodium album ferredoxins too. The localization of tyrosine fluorescent maximum at 340nm in the ferredoxins is not due to interaction of tyrosine with the iron-sulfur center. The data obtained allow to suggest that the tyrosine residues in ferredoxins have different environments.

Adrenal and hypothalamic structure has been studied in mice at functional inhibition of the sympathetic region of the vegetative nerve system by means of antibodies against the nerve growth factor. Routine histological, histochemical, morphometric, electron microscopic and radioautographic methods have been applied. In the experiment the hypothalamic region is in the state of a continuous functional stress which is evident from enlargement of neurons and their nuclei in the macrocellular neurosecretory nuclei of the hypothalamus. The method of radioautography proves increasing activity in synthetic processes taking place in supraoptic, paraventricular and ventromedial nuclei of the hypothalamus and in the medial habenular nucleus of the epithalamus. In 30-day-old mice certain structural changes have been revealed in the adrenals demonstrating an increasing activity in their cortex: blood vessels are dilated, cholesterine, lipid and ascorbic acid granules are not evenly distributed, enzymatic activity in cytoplasm of adrenocorticocytes is increased. Ultramicroscopic destructive and regenerative alterations have no definite zonal specificity, nevertheless they are more pronounced in the fascicular zone. Radioautographic and morphometric investigations demonstrate an increasing functional activity in glomerular and fascicular adrenal zones. Taking into account morphologic demonstration of functional stress in hypophysial adenocytes in the same animals (Molostov O. K., 1974), it is possible to conclude that lesions in the sympathetic system center result in adaptive reaction of the hypothalamo-hypophysial system which, in its turn, produces reactions in the adrenals and in the vascular complex. This interconnection is accompanied by the reaction depending on breaking off direct sympathetic effects in the adrenals and vessels.

A synthetic route to 5,8,11,14,17-eicosapentaynoic acid, an acetylenic precursor of 5Z,8Z,11Z,14Z,17Z-eicosapentaenoic acid, has been developed based on condensation of a propargyl synthon with omega-acetylenic fragments. Physico-chemical constants and spectral characteristics (IR, 1H-NMR, and mass-spectrometry) of the target and intermediate compounds are given.

Background Hemozoin is the pigment produced by some blood-feeding parasites. It demonstrates high diagnostic and therapeutic potential. In this work the formation of co-called hemozoin “knobs” – the bile duct ectasia filled up by hemozoin pigment - in Opisthorhis felineus infected hamster liver has been observed. Methods The O. felineus infected liver was examined by histological analysis and magnetic resonance imaging (MRI). The pigment hemozoin was identified by Fourier transform infrared spectroscopy and high resolution electrospray ionization mass spectrometry analysis. Hemozoin crystals were characterised by high resolution transmission electron microscopy. Results Hemozoin crystals produced by O. felineus have average length 403 nm and the length-to-width ratio equals 2.0. The regurgitation of hemozoin from parasitic fluke during infection leads to formation of bile duct ectasia. The active release of hemozoin from O. felineus during in vitro incubation has also been evidenced. It has been shown that the hemozoin knobs can be detected by magnetic resonance imaging. Conclusions In the paper for the first time the characterisation of hemozoin pigment extracted from liver fluke O. felineus has been conducted. The role of hemozoin in the modification of immune response by opisthorchiasis is assumed. Electronic supplementary material The online version of this article (doi:10.1186/s13071-015-1061-5) contains supplementary material, which is available to authorized users.

Models of slopes were used to measure elastic strains. The formulae presented were used to calculate the stresses. The arrangement of the potential failure surface at various angles of slope was determined on the basis of a set of criteria. A method of determining the stability of slopes is proposed on the basis of the experimental data. It consists in determining the safety factor as the ratio of the sum of the resisting stresses along the failure surface and the sum of the tangential stresses. Calculations made by the recommended method give higher values of the safety factor, which are closer to actual data.