[Biofilm control in urological practice].

Urinary tract infections (UTIs) have long been among the most common diseases. In the structure of the general infectious morbidity, UTIs rank second after acute respiratory viral infection. Every year, researchers note an increasing number of mutations in the genomes of bacteria that cause infectious diseases, which leads to the formation of more and more aggressive forms of pathogens. Patients with infectious diseases of the urinary system have the highest risk of biofilm formation, the frequency of which is directly proportional to the length of time the urethral catheter is located and accounts for more than half of all nosocomial infections. The presence of resistant strains of pathogenic bacteria and the development of bacterial biofilms are major problems in the treatment of urinary tract infections. The increasing number of nosocomial bacterial strains in the hospital increases the postoperative bed-day, the frequency of readmission and the number of antibacterial drugs used. In light of increasing antibacterial resistance, the use of medical resources is dramatically increasing, which ultimately leads to an increase in the cost of treatment. Along with this, the selection of resistant strains brings to the fore both the rational use of antibacterial drugs and the search for alternative methods of therapy. This review of publications on the problem of bacterial biofilm formation in urological practice demonstrates updated information on the role of enzymes, probiotics, and bacteriophages in preventing biofilm formation on various medical biomaterials, such as urethral catheters.

[ORGANIZATION OF MEDICAL CARE FOR ELDERLY PATIENTS UNDER THE CONDITIONS OF THE COVID-19 PANDEMIC].

The first report of the new coronavirus infection (COVID-19) appeared at the end of December 2019 and in March,2020 the World Health Organization announced COVID-19 a pandemic. The steady number of newly detected cases increase predetermined the modernization of the global healthcare system, shifting the paradigm of fighting with the COVID-19 pandemic towards maximum resource conservation. The change in the medical care provision for infectious patient's approach led first to a gradual decrease, and then to a complete cessation of planned surgical treatment, outpatient examinations, as well as observation of high-risk patients, which primarily include elderly patients. As a result of this, the key objective of this systematic review was to analyze sources of existing practice of providing urological care to patients of the older age group in the context of the COVID-19 pandemic. In accordance with the search for the keywords, the study reflects world and its own experience of MSMSU Urology Department in the treatment of age-related patients in the current epidemiological situation. The analysis showed that infectious complications from the urinary system take a leading position among the common complications inherent in elderly patients with COVID-19. The development of catheter-associated infection, the occurrence of antibiotic-resistant forms of bacteria, asymptomatic bacteriuria are only a small part of the problems clinicians have to face in newly profiled departments.

[Immune response to lower urinary tract infections].

Urinary tract infections are one of the most common and widespread infectious diseases. A certain role in etiopathogenesis may play genetic predisposition, as well as a decrease in antiadhesive properties and an increase in urothelium permeability due to incompetence of bladder glycosaminoglycan layer. The prevalence of infectious diseases increases significantly with age, as well as in patients with chronic diseases. The introduction of modern biotechnology has allowed clinicians to greatly expand therapeutic armamentarium, while having a number of advantages, including minimal frequency of complications and adverse events, the possibility for long-term use, accessibility, and etc. Priority research areas include the study of toll-like receptors, which are transmembrane proteins that provide pathogen recognition and activate the immune response. The role of these receptors in the development of the immune response to urinary tract infections was evaluated in our study, which allows to predict the course of the disease and to increase treatment efficiency.

Effects of Catechin on Activity of Angiotensin-Converting Enzyme and Generation of Reactive Oxygen Species in Rat Aorta.

Activity of angiotensin-converting enzyme (ACE) and intensity of ROS generation in the aorta were studied in male Wistar rats intraperitoneally injected with a mixture of (+) and (-) stereoisomers of catechin. ACE activity in aortal segments was evaluated by hydrolysis of hippuryl-histidine-leucine; ROS generation was measured by oxidation of dichlorodihydrofluorescein. The dynamics of ACE activity and intensity of ROS generation in the aorta after catechin administration and their dependence on the catechin dose were studied. The effects of dihydroquercetin and fucoidin on the studied parameters were analyzed. Catechin increased ACE activity; the maximum increase was achieved in 3 h after administration. Catechin dose producing a half-maximum increase in ACE activity was 0.04 µg/kg. The effects of catechin on ACE activity was attenuated by dihydroquercetin and completely abolished by fucoidin. Catechin did not enhance ROS production in the aorta, and in a dose of 0.1 µg/kg even inhibited this process. It is hypothesized that isomers of catechin produce opposite effects on ROS generation in the aorta.

[Prospects of using bacteriophages in urological practice].

In modern clinical practice, antimicrobial resistance creates a significant problem for the effective metaphylaxis of various infectious and inflammatory diseases of the urinary system. Annually, researchers note an increasing number of mutations in the genomes of bacteria that cause infectious diseases, which leads to the appearance of more aggressive strains. The inefficiency of antibiotic therapy requires to a search for alternative methods for treatment and prevention of infectious diseases. use of viruses that infect bacteria (bacteriophages) represent one of such methods. A literature review of recent publications indicates that phage therapy has been gained significant increase. The general aspects of phage therapy, mechanism of action, as well as the existing possibilities and limitations of phage therapy in treatment and prevention of infectious diseases of the urinary system are highlighted in this article.

Blood Pressure Changes After Exposures Increasing Angiotensin-Converting Enzyme Activity and After Its Normalization with Dihydroquercetin in Male Wistar Rats.

Changes in BP and HR were assessed after exposures increasing activity of angiotensin-converting enzyme: ionizing radiation, NO synthase inhibitor (L-NAME), and dexamethasone. Effects of dihydroquercetin and angiotensin-converting enzyme inhibitor enalapril on activity of this enzyme, BP, and HR were also evaluated under these exposures. Wistar male rats were subjected to X-ray irradiation in a dose of 2.5 Gy. Angiotensin-converting enzyme activity in the aorta sections was determined by Hip-His-Leu hydrolysis. BP and HR were recorded using a non-invasive tail-cuff method and PowerLab 8/35 software. BP and HR were not altered with the increase in activity of angiotensin-converting enzyme after irradiation. In case of prolonged (7 days) treatment with NO synthase inhibitor and dexamethasone, the increase in enzyme activity was accompanied by elevation of BP and, in the case of NO synthase inhibitor, HR reduction. Dihydroquercetin normalized the enzyme activity and lowered BP, but not to the normal level. Enalapril normalized BP, increased by NO synthase inhibitor solution intake; at the same time, the angiotensinconverting enzyme activity decreased more than 2-fold in comparison with the normal.

Dihydroquercetin and Fucoidin Inhibit the Increase of Angiotensin-Converting Enzyme Activity in the Rat Aorta after Irradiation.

The time course of angiotensin-converting enzyme activity in the rat aorta after fractionated exposure to ionizing radiation and the effects of dihydroquercetin and fucoidin on this parameter were studied. Male Wistar rats were exposed to single or repeated (fractionated) X-ray radiation in a dose of 2.5 Gy at 200 kV. Activity of angiotensin-converting enzyme in aorta segments was evaluated 2 h after the last exposure by hydrolysis of hippuryl-histidineleucin substrate. Enzyme activity in the rat aorta was higher than normally after all the studied doses of fractionated exposure (2.5 Gy per fraction) with the maximum effect after the total dose of 7.5 Gy (3 fractions). Fucoidin, a blocker of endothelium receptors realizing the leukocyte adhesion to the endothelium, and flavonoid dihydroquercetin inhibiting expression of adhesion molecules in the endothelium abolished the increase in activity of angiotensinconverting enzyme in the rat aorta after single exposure; moreover, dihydroquercetin reduced significantly the effect of fractionated exposure. These data indicate that leukocyte adhesion to the endothelium is an important factor contributing to the increase of angiotensin-converting enzyme activity in the aorta.

[Evaluation bacteriological analysis of urine in patients with long-term bladder drainage].

INTRODUCTION: The experience of comparative evaluation of the effectiveness of various types of urethral catheters in prevention of catheter-associated infection is described in this article. MATERIALS AND METHODS: The study included 69 patients treated at the CCH n.a. S.I. Spasokukotsky in the period from December 2017 to March 2018. The average age of patients was 67.5 years. In all patients, the bladder was drained by a two-way Foley catheter No. 16-18 Ch (100% silicone). In the 1st group (n=18), the bladder was drained with a standard urethral uncoated catheter, in the 2nd (n=16) - with a silver impregnated urethral catheter, in the 3rd (n=15) - with an urethral catheter coated with nitrofuran, in the 4th (n=20) urethral catheter with the possibility of controlled irrigation of the bladder and urethra with antiseptic solutions and (a new model of the urethral catheter developed during cooperative work of the Moscow State University of Medicine and Dentistry n.a. A.I. Evdokimov Urology Department and National Medical Research Center of Obstetrics, Gynecology and Perinatology n.a. V.I. Kulakov). RESULTS: The bladder was drained by Foley urethral catheter for more or equal 15 days. A microbiological study of urine (on the example of clinical isolates of conditionally pathogenic microorganisms) with preparation of an inoculum, inoculation of nutrient media, counting cultures of pathogenic bacteria and determining the sensitivity of pathogenic bacteria to antibiotics was carried out. The study showed the effectiveness of the new urethral catheter model in patients with long-term bladder drainage. CONCLUSIONS: Conducting multicenter studies evaluating the effectiveness of the proposed urethral catheter model with the inclusion of a larger number of patients will reduce the economic costs, associated with treating patients with prolonged bladder drainage in the long term by reducing the number of nosocomial infection cases and reducing postoperative day.

Dihydroquercetin Does Not Affect Age-Dependent Increase in Blood Pressure and Angiotensin-Converting Enzyme Activity in the Aorta of Hypertensive Rats.

We analyzed changes in angiotensin-converting enzyme activity in the aorta of hypertensive SHR rats against the background of age-related BP increase (from week 7 to 14) and the effect of dihydroquercetin on BP rise and angiotensin-converting enzyme activity. Normotensive WKY rats of the same age were used as the control. BP and activity of angiotensin-converting enzyme in the aorta of SHR rats increased with age. Dihydroquercetin in doses of 100 and 300 µg/kg per day had no effect on the increase of these parameters; dihydroquercetin administered to 14-week-old WKY rats in a dose of 300 µg/kg reduced activity of the angiotensin-converting enzyme. Thus, the early (7-14 weeks) increase in BP and angiotensin-converting enzyme activity in the aorta of SHR rats was not modified by flavonoids (dihydroquercetin) in contrast to other rat strains and humans, which is indicative of specificity of hypertension mechanism in SHR rats.

[Screening of Organisms Producing Inhibitors of 15-Lipoxygenase Among Micromycetes.]

The effects of extracts from the mycelium of Lecanicilium lecaniiNo.169, Beauveria fellina No.7 and Beauveria bassianaNo.15 on the activity of 15-lpoxygenase (15-LO) recovered from rat reticulocytes was investigated. The activity of 15-LO was determined by oxidation of linolic acid. The extract from the mycelium of the fungal complex was shown to inhibit 15-LO (IC50 of 12 mcg/ml). The inhibitory effect of the combined extract on 15-LO was due to the substances recovered from Lecanicilium lecanii No.169. The extract fractions responsible for the activity were determined and the compounds containing the fractions were identified. They proved to be 10 - 4-hydroxybenzoic acid and 4-hydroxybenzyl alcohol and genistein, a flavonoid from fraction 11. The possible role of the inhibitory effect of the compounds on 15-LO in the antiatherosclerotic activity of the fungal extract is discussed.

Effect of perfluorodecalin on viability of Ehrlich ascites tumor cells under conditions of hypoxia.

Perfluorodecalin increased survival rate of Ehrlich ascites tumor cells under pathological conditions of hypoxia in combination with hyperkalemia. High potassium medium increased the content of lysophospholipids in samples, while in the presence of perfluorodecalin, phosphatidylethanolamine level decreased.

Effect of melafen on structure and function of liposome and ehrlich ascitic carcinoma cell membranes.

The effects of melafen (plant growth stimulant) on membrane structure and functions of animal cells were studied. The process of signal transduction from cell surface to intracellular structures and conformation changes in membranes in the presence of this substance were studied by light scatter and differential scanning microcalorimetry. Melafen in a wide range of concentrations (10(-13)-10(-3) M) inhibited Ca(2+) signal system involved in the function of Ca(2+)-dependent K(+) and Cl(-) channels in Ehrlich ascitic carcinoma cells. Being a hydrophilic substance, melafen had little effect on the lipid phase of artificial membranes, but impaired the function state of transformed cell. The importance of studies of transformed cells causes no doubt because of increasing incidence of diseases associated with uncontrolled cell division.

Changes in the structure and functions of membranes in erythrocytes and Ehrlich ascites carcinoma cells under the influence of a new generation hybrid antioxidant IKhFAN-10.

We studied the effect of a new generation hybrid antioxidant IKhFAN-10 on the structure and function of cell membranes (organization of the lipid bilayer and proteins and activity of ion channels). The test preparation proposed for the therapy of neurodegenerative diseases modified properties of membranes in erythrocytes and Ehrlich ascites carcinoma cells and affected functional activity of cells. We determined the doses of this antioxidant, which did not cause side effects.

Acceleration of fibril formation and thermal stabilization of collagen fibrils in the presence of taxifolin (dihydroquercetin).

We studied the effect of flavonoid taxifolin (dihydriquercetin) on the structure and thermal stability of collagen I fibrils. Taxifolin accelerated fibril formation with reconstruction of periodical cross-striation characteristic of these fibrils. Differential scanning calorimetry showed elevation of melting temperature of collagen fibrils formed in neutral or weakly alkaline media, but not of individual tropocollagen molecules in acid medium. Taxifolin capacity to stimulate fibril formation and promote stabilization of fibrillar forms of collagen can be used in medicine.

Effect of Ca2+ gradient on the structure of sarcoplasmic reticulum membranes.

The structure of sarcoplasmic reticulum membranes was studied in the presence of modeled transmembrane Ca2+ gradient corresponding to the status of Ca2+ depot at different stages of the muscle contraction-relaxation cycle in health and disease. Various sites of the membrane were characterized using spectral analysis of tryptophan, pyrene, and merocyanine-540 fluorescence without evaluating specific changes in the molecules of membrane components (Ca2+ -ATPase, ryanodine receptor, and lipids). The transmembrane Ca2+ gradient modulates the protein-lipid interactions and structural characteristics of the membrane. The proposed model can be used for studies of the effects of pharmacologically active substances and endogenous regulators.

Fusion and endocytosis of anionic liposomes with Ehrlich ascitic carcinoma cells.

Polyethylene glycol 300 and low pH of the incubation medium initiate fusion of anionic lipid liposome membranes with Ehrlich ascitic carcinoma cell membranes. Some liposomes are endocytosed in cells and are distributed near the inner surface of the membrane. Liposome membranes spontaneously fuse with the cells under certain conditions.