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In the work an there is given an assessment of the working conditions during intense visual activity without the use of displays medium and optical devices. It is proved that the indices of evaluation of the light environment in accordance with "Guidelines for hygienic assessment of factors working environment and labor process" P 2.2.2006-05 R 2.2.2006-05 were substantiated to be been supplemented by indices of uneven brightness and color temperature of the light source. It is confirmed that the intense visual work is a meaningful evaluation of the constraint, especially in terms of sensory loads. In the dynamics of the working day there was revealed the deterioration of the visual analyzer and psychoemotional state. In periodic medical examinations there was noted a marked gain in revealed pathology of diseases of the eye and adnexa with increasing work experience. A method for estimation of the risk in people doing intense visual work, taking into account the evaluation of the light environment, intensity of work, dynamics of the functional state during the shift has been proposed.

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Protein translocation in the ER (endoplasmic reticulum) and N-glycosylation are fundamental processes essential for the normal functioning of eukaryotic cells. They are the initial steps in the intracellular pathway that are followed by secretory proteins and membrane proteins of the endomembrane system and the plasma membrane. The translocation and concurrent N-glycosylation of these proteins take place on a large molecular machine, the TC (translocon complex), which is associated with membrane-bound polysomes. Segregation of TCs into a differentiated domain of the ER, the rough ER, may increase the efficiency of protein synthesis on membrane-bound polysomes. Our research is concerned with the assembly, functional organization and dynamics of the TCs in the ER, and their contribution to the functioning and the morphological appearance of this organelle. We hypothesize that the TCs form higher-order structures defining the rough domain of the ER. These structures, which are immobilized or diffuse slowly in the plain of the ER membrane, may be formed and stabilized by mRNAs interconnecting the TCs, by cytoskeletal elements and/or by hypothetical proteins that form links between the TCs. We have established the M3/18 cell line, which expresses the GFP (green fluorescent protein)-Dad1 fusion protein quantitatively and functionally incorporated into the OST (oligosaccharyltransferase). GFP-Dad1 can be used as a reporter molecule for the lateral mobility of the TCs since the OST is tightly associated with the complex. As determined by FRAP (fluorescence recovery after photobleaching), the lateral mobility of GFP-Dad1-tagged TCs was much more restricted than expected from the estimated size of the TC and can be affected by the functional state of the TCs. Currently, we are studying the possible involvement of cytoskeletal elements in the organization of the TCs. Our data suggest that microtubules also play a role in the immobilization of the TCs.

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The topography of rat glycerophosphate acyltransferase (GAT) in the transverse plane of the mitochondrial outer membrane (MOM) was investigated. Computer analysis of the amino acid (aa) sequence derived from rat mitochondrial GAT cDNA (GenBanktrade mark accession nos. and ) predicts the presence of two possible transmembrane domains (aa 473-493 and 574-594) separated by an 80-aa stretch (aa 494-573). To determine the actual orientation of the native protein, we prepared anti-peptide antibodies to three regions: one in between (aa 543-559) and the other two (aa 420-435 and 726-740) flanking the two putative transmembrane regions. Both immunoreaction and immunoprecipitation experiments employing intact and solubilized mitochondria indicate that regions on the N- and C-terminal sides of the transmembrane regions are sequestered on the inner surface of the MOM, while the region between the transmembrane domains is present on the cytosolic face of the MOM. Additionally, two green fluorescent protein (GFP) fusion proteins consisting of full-length GAT fused to GFP at either the C terminus or inserted 115 amino acids from the N terminus were also constructed to determine the orientation of the N and C termini. COS-1 cells expressing these fusion proteins were fractionated to obtain mitochondria. Protease digestion of intact and solubilized COS-1 cell mitochondria revealed that the GFP domains of these fusion proteins are sequestered on the inner side of the MOM. The present findings indicate that GAT is a dual-spanning, transmembrane protein adopting an inverted "U" conformation in the transverse plane of the MOM, where the N and C termini are sequestered on the inner surface of the MOM, while aa 494-573 are exposed on the cytosolic surface of the MOM.

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In five strains of Mycoplasma gallisepticum, a protein with a molecular mass of about 40 kDa was detected by immunoblotting with anti-pig brain tubulin polyclonal and monoclonal antibodies. In eight other mycoplasma species similarly tested no reaction was observed. Thin serial sections of M. gallisepticum and Acholeplasma laidlawii cells examined by transmission electron microscopy revealed a submembrane system of tubules in M. gallisepticum but not in A. laidlawii. The intracellular spatial distribution of the tubular structures was reconstructed. Thin sections of M. gallisepticum treated with anti-tubulin antibodies and colloidal gold particles (immunogold labelling) revealed distinct labelling of the tubular system. Analysis of the tubular structures by high resolution electron microscopy and optical diffraction showed their helical organization to be: diameter 40 nm, helix pitch approximately 20 nm and electron-transparent core 10 nm in diameter. A possible involvement of the tubular system in mycoplasma motility is suggested.

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In all the strains of M. gallisepticum investigated, a protein with apparent molecular weight 40 kDa was revealed by immunoblotting with polyclonal anti-calf brain tubulin antibodies and monoclonal anti-chicken alpha-tubulin antibodies. In other 8 investigated Mycoplasma species no positive reactions with the same antibodies were found. The M. Gallisepticum cells were examined under electron microscope on fine serial sections and on some sections going at different angles to the long cell axis. Undermembrane system of tubules was revealed and the intracellular pattern of the tubular structures were reconstructed. The immunoelectron microscopic data suggest that tubulin-like protein may be included into the structures.

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Differences in virulence of two Mycoplasma gallisepticum strains, S6 and A5969, are confirmed in experiments with chickens. Macromolecular discrepancies detected between these two strains are concerning the genomic size, electrophoretic spectra of DNA and proteins. Cross immunoblotting data with polyclonal and monoclonal antibodies reveal major immunogens of protein nature in both the strains. Homologous proteins with different electrophoretic mobility are detected in other four M. gallisepticum strains. A possible participation of these proteins of M. gallisepticum in adhesion to the host cells is discussed.

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In a previously healthy woman aged 36 years with 16% of the skin surface burned, an injection of sombrevin elicited basilar artery thrombosis which manifested in isolation syndrome (IS) with temporary left sight paresis and vertical ocular divergence. Pathological investigation revealed the infarct involving right brain pedicle and pontine paramedian regions.

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