[Identification of Clinical Isolates of the Bacillus cereus Group and Their Characterization by Mass Spectrometry and Electron Microscopy].

Bacillus cereus is a spore-forming bacterium found in the environment mainly in soil. Bacillus spores are known to be extremely resistant not only to environmental factors, but also to various sanitation regimes. This leads to spore contamination of toxin-producing strains in hospital and food equipment and, therefore, poses a great threat to human health. Two clinical isolates identified as B. cereus and B. cytotoxicus were used in the present work. It was shown that their calcium ion content was significantly lower than that of the reference strains. According to electron microscopy, one of the SRCC 19/16 isolates has an enlarged exosporium, and the SRCC 1208 isolate has large electron-dense inclusions of an unclear nature during sporulation. We can assume that these contain a biologically active component with a cytotoxic effect and possibly play a role in pathogenesis. Comparative chemical, biochemical, physiological, and ultrastructural analysis of spores of clinical isolates and reference strains of B. cereus was performed. The results we obtained deepen our understanding of the properties of spores that contribute to the increased pathogenicity of B. cereus group species.

Actual approaches to the transportation of biological samples at low temperatures.

Taking into account the impact of shipment method of biosamples is necessary for obtaining high-quality biological samples in biobanking and laboratory research. The impact of liquid nitrogen, dry ice and cold accumulators on the quality of biological markers was considered, as well as recommendations to reduce the impact of these methods of shipment. The liquid nitrogen provides the best preservation of samples, however, dry ice is used much more often during their transportation. When transporting certain types of cells using dry ice, there is the way to use CryoStor CS1 and Cell Banker 1 cryoprotectors. The dry ice has a significant effect on both the pH of liquid biological samples and the coagulological parameters of plasma samples. The penetration of CO2 into the sample leads to changes in the parameters of PTT and APPT, as well as to decrease the protein C and fibrinogen level under certain conditions. Serum and plasma samples exposed to dry ice for more than 16 hours should be thawed open at room temperature, or instead of it should be kept at -80 °C for 24 hours to avoid changes in coagulation parameters, The use of cold accumulators is unacceptable for long-term shipment of serum and plasma containing unstable biomarkers because of insufficiently low temperature (increase over time to -25 °C and above). Besides, metal pellets can be used as cold storage batteries at low temperatures (up to -80 ° C), but they are not as effective as dry ice, since it is able to hold the required temperature for much longer.

[Relationship between blood lipid spectrum and activity of the disease in patients with rheumatoid arthritis].

Patients with rheumatoid arthritis (RA) are at risk of cardiovascular disorders. Pathogenesis of rapidly developing atherosclerosis in RA remains to be elucidated. The aim of this study was to compare cholesterol content in serum lipoprotein subfractions in patients with RA and healthy subjects and to establish relationship between lipid profile variations, severity of the disease, and plasma levels of anti-inflammatory cytokines. The study included 15 patients with active RA and 120 healthy subjects of comparable sex and age. RA was found to be associated with a significant decrease of cholesterol of high density (HDL2) and intermediate density (IDL) lipoproteins and its elevation in low density lipoproteins (LDL1-3). There was negative correlation between the latter parameter and disease activity index. No relationship between lipoprotein cholesterol and serum interleukins (IL-6, IL-8) TNF-alpha, and IFN-gamma) was documented. It is concluded that patients with RA exhibit proatherogenic changes of cholesterol content in different lipoprotein subfractions related to the severity of the disease. Further studies are needed to elucidate molecular mechanisms of dyslipidemia in RA and to ensure the choice of optimal targets for therapeutic modalities reducing the risk of cardiovascular disorders.

[Effect of yeast disintegration conditions on protein properties]. / Izuchenie vliianiia uslovii dezintegratsii drozhzhei na svoistva belkov

The influence of the cellular treatment with the aid of a vibrocolloidal mill on the model proteins--albumin and yeast glutelin was studied. The treatment of the model proteins in methylene chloride using the vibrocolloidal mill did not change the protein solubility. By analytical centrifugation, electrophoresis in polyacrylamide gel and gel filtration it was shown that these proteins underwent no destruction.