Evaluation of the potential pathogenicity of microorganisms associated with urinary calculi.

Due to the prevalence of postoperative complications in the treatment of urolithiasis, the study of the contamination of urinary calculi and the potential pathogenicity of isolated bacteria is of great importance in laboratory diagnostic practice. It has been shown that uropathogenic bacteria are found in the composition of urinary stones in 65±7.1% of cases, mainly representatives of the Enterobacteriaceae and Staphylococcaceae families. Bacteria of the generas Escherichia, Enterococcus, Staphylococcus were most frequently detected. The analysis of biofilm activity and antibiotic resistance in 50 uropathogenic strains was carried out. It was shown that all the studied strains were resistant to at least two tested drugs, and the average value of the multiple resistance index was 0.51. When cultured on nutrient agar with Congo red, it was shown that more than half of the tested strains have high biofilm activity and about 80% potential for biofilm formation. The greatest biofilm activity was observed in bacteria of the generas Escherichia, Klebsiella, Enterobacter, Staphylococcus.

Controlled Fragmentation of Urinary Stones as a Method of Preventing Inflammatory Infections in the Treatment of Urolithiasis (Experience in Successful Clinical Use).

The introduction of technologically advanced methods of lithotripsy into medical practice changes the nature of postoperative complications. Among them, the main complications are inflammatory infections. This largely determines the search for new, improved methods of stone fragmentation avoiding small stone fragments and dissemination of the pelvicalyceal system of the kidney with stone-associated infection. The authors have developed a method for controlled stone fragmentation using a continuous-wave diode laser with a hot-spot effect at the optical fiber end. The aim of the study was to evaluate the efficacy of controlled urinary stone fragmentation using a continuous-wave diode laser with a highly heated distal end of the optical fiber light guide as a method of preventing inflammatory infections in clinical practice. MATERIALS AND METHODS: We analyzed 1666 case histories of urolithiasis patients who underwent percutaneous nephrolithotripsy/ nephrolithoextraction and contact ureterolithotripsy/ureteroextraction, we also performed a prospective analysis of complications based on the Clavien-Dindo classification in 90 patients who underwent fine fragmentation of stones with various lithotripters: ultrasonic, pneumatic, and holmium laser. The method of controlled stone fragmentation by a diode laser with a hot-spot effect was tested on postoperative samples of 26 renal calculi. For the first time in clinical practice, this method was tested in the bladder cavity (n=10). RESULTS: In the percutaneous nephrolithotripsy group, postoperative infectious and inflammatory complications occurred in 34.1% of cases, in the percutaneous nephrolithoextraction group - in 24.6%, in the contact ureterolithotripsy group - in 7.8%, in the ureterolithoextraction group - in 2.5%. The analysis made it possible to identify factors promoting the development of infectious and inflammatory complications. For the first time in clinical practice, there were successfully performed ten operations of stone fragmentation using a continuous-wave diode laser with a hot-spot effect. Controlled coarse fragmentation of stones providing the possibility to reduce the number of infectious and inflammatory complications was performed in the bladder as a model for testing the method. CONCLUSION: The method of laser-induced controlled coarse fragmentation of stones with a hot-spot effect, developed and tested in clinical practice, is promising for the prevention of infectious and inflammatory complications in patients with potentially infected stones since their fine fragmentation and, consequently, spread of stone-associated toxins and microflora within the urinary system is avoided.

[Evaluation of the influence of culturing on the intensity of biofilm formation by Klebsiella pneumoniae strains.] / Влияние условий культивирования на интенсивность биоплёнокообразования штаммами Klebsiella pneumoniaе.

Due to the prevalence of biofilm infections caused by Klebsiella pneumoniae, in laboratory diagnostic practice it has a great importance to obtain a standard model of Klebsiella biofilm for evaluating the bactericidal effect and effectiveness of antimicrobial drugs. Describes the method of Klebsiella biofilms formation in vitro. The intensity of biofilm formation was evaluated by the ability of bacteria to bind the crystal violet. The degree of film formation was measured by optical density. The presence of an intercellular matrix was confirmed by staining of Congo-red solution followed by light microscopy. The effect of exogenous and endogenous factors on biofilm formation by K. pneumoniae strains was investigated. The influence of the nutrient composition, the age of the culture («daily¼, «weekly¼), the presence of oxygen and the temperature conditions were studied. The nutrient composition of the medium significantly influenced on biofilm formation of K. pneumoniae: DMEM stimulated biofilm formation in most strains in vitro compared to TSB. The age of the culture (daily, weekly) did not significantly affect the biofilm formation of Klebsiella. At the same time, the temperature of culturing and the presence of oxygen can both stimulate and inhibit biofilm formation, depending on the strain under study. Most strains of Klebsiella better form a biofilm under aerobic conditions at 37º C.

[Enzyme preparations and biocatalytic processes in the food industry].

Enzyme preparations are essential to biotechnological processes for the production of food. Classification of enzymes, the specificity of their action on various substrates and processes of obtaining enzyme preparations based on various microorganisms-producers of enzymes are presented. Overview of the world and internal market of enzyme preparations used in the food industry is provided. The issues of efficient bioconversion of different plant materials to improve the quality of juices, fruit drinks, reducing the viscosity and increasing the productivity of biologically valuable components for functional products are considered; microbial raw materials - to produce protein or amino acid and vitamin enriched foods, as well as food ingredients; animal raw materials - for intensification of technological processes, for processing of wastes of meat, dairy industry, as well as in cheese making to improve the quality of products. The review is of scientific and practical interest for specialists in the field of biotechnology of food production of high quality food obtained by the enzymatic conversion of different types of agricultural raw materials.