Background and Aim: With the development of industrial maintenance technology, a group of pathogens called avian pathogenic Escherichia coli (APEC) became very common. The initiation, development, and outcome of the infectious process mediated by virulent APEC strains occur through a decrease in the colonization resistance of the intestine, an immunobiological marker of homeostasis stability in susceptible species. This study focused on the pathogenetic features of colibacillosis and the morphological features of E. coli. Materials and Methods: Clinical, immunological, bacteriological, and histological studies were conducted on 15-day-old white Leghorn birds (n = 20). The birds were divided into two groups: Control group (Group I; n = 10) with birds intranasally inoculated with 0.5 mL of 0.9% NaCl solution and experimental group (Group II; n = 10) with birds intranasally inoculated with 0.5 mL of an E. coli suspension at 1 billion/mL. Results: During the biofilm formation, clusters of microcolonies were formed as a gel-like intercellular matrix that accumulated due to cell coagulation. The intercellular matrix “glues” heteromorphic cells together and forms a structure of densely packed heteromorphic cells arranged in an orderly manner and growing in different directions. During the experimental reproduction of E. coli, excessive growth was observed in material isolated from poultry. Pathogenic E. coli strains implementing virulence factors adhered to the receptors of erythrocytes, alveolocytes, and enterocytes. Multicellular heterogeneous biofilms, united by an intercellular matrix, were located at the apical poles of the respiratory tract alveolocytes and enterocytes of the terminal ileum villi. Many bacteria exudate containing desquamated epithelial cells with an admixture of mucus, and polymorphonuclear leukocytes were detected in the lumen of the birds’ abdominal organs. Invasive bacteria damaged the epithelial layer, violated the endothelial layer of blood vessels, and developed inflammatory hyperemia of the lamina propria of the respiratory and digestive systems’ mucous membrane. A correlative dependence of changes developed by the type of delayed hypersensitivity reaction was established. Signs of accidental transformation of the thymus, atrophy of the bursa of Fabricius, disseminated thrombosis, and septic spleen developed. Moreover, toxic cardiomyocyte dystrophy, signs of congestive vascular hyperemia, massive disintegration of lymphocytes, macrophage reactions, perivascular edema resulting from the release of plasma, and shaped blood elements were detected. Conclusion: The development and outcome of the infectious process in escherichiosis primarily depend on the homeostasis stability of susceptible species and virulence factors of the pathogenic microorganisms. One of the selected strains, E. coli O78:K80 displayed the highest ability to form biofilms. Its strong adhesion ability to bird erythrocytes was demonstrated. Deepening the scientific knowledge of the interaction between eukaryotes and prokaryotes will contribute to a better understanding of the pathogenetic aspects of avian escherichiosis and eventually find promising anti-adhesive drugs that could reduce primary bacterial contamination in vivo and in vitro. Keywords: avian colibacillosis, biofilm formation, Escherichia coli, intercellular matrix, poultry.

One of the most important functions of the oral fluid is to maintain oral homeostasis. In-office teeth whitening systems are able to change the mineral metabolism and the activity of a number of enzymes in the oral fluid, but there are conflicting data in publications about this. The aim of this study was to compare the effect of Opalescense Boost, ZOOM Advance POWER, and ZOOM Phillips White Speed, which contain different percentages of hydrogen peroxide, on the performance of oral fluid. After the procedure of whitening teeth with the studied in-office systems, the concentration of calcium in the oral fluid increased, and the activity of alkaline phosphatase decreased. Calcium levels returned to baseline values after 30 days, and alkaline phosphatase activity returned after 14 days. There was no significant difference in the changes in calcium concentration and alkaline phosphatase activity between different tooth whitening systems. Chemical teeth whitening with the Opalescense Boost system caused the largest change in the activity of superoxide dismutase in the oral fluid compared to the ZOOM Advance POWER and ZOOM Phillips White Speed photocatalytic teeth whitening systems. An increase in the activity of superoxide dismutase by +75.5% was shown immediately after the procedure of teeth whitening with the Opalescense Boost system, which indicated an increase in the power of antioxidant defense mechanisms. To assess the effectiveness and safety of using various whitening systems, it is possible to study the dynamics of the activity of superoxide dismutase, which reflects the processes of antioxidant protection of the oral cavity.

Objective. To determine the cause of variable clinical efficacy of local anesthetics containing active substances (articaine and epinephrine) and to substantiate the indicators for their selection in trade names. Material and methods. In our experiment, we used a mathematical approach to calculate the ratio of ionized and non-ionized forms of anesthetic drugs found in various biological fluids and human tissues. Articaine-based anesthetics containing epinephrine at a dilution of 1:100.000 or 1:200.000 were chosen for the study: Articain-Bynergy, Brilocaine, Articaine Inibsa, Orablok, Primakain, Septanest with adrenaline, Ubistezin and Ultracain with adrenaline. We obtained appropriate data from analytical passports or literature databases. Results. Articaine-containing local anesthetics are bases by their chemical nature. Being subjected to hydrolysis, these anesthetics realize their direct effect, i.e. reversible disturbance of nerve cell excitation and cessation of pain impulses for a certain period of time. Prolongation of these effects depends on the dose of injected artificial adrenaline. When comparing some characteristics of articaine-containing local anesthetic substances with epinephrine, we found different pH of solutions depending on concentration. Adrenaline is also a base that must be kept from hydrolysis. Conclusion. Lower pH of articaine-containing drug is accompanied by higher percentage of stable ionized form of local anesthetic.

Relevance. As medical research develops, more and more attention is being paid to the study of elemental changes in cancer patients not only as a marker of the disease, but also as a possible complication of the disease. The aim was to study changes in the level of essential and toxic trace elements in patients who have undergone antitumor therapy (AT) for malignant neoplasms (MN). Materials and Methods. As part of a retrospective monocenter study, a group of 214 patients from the Russian Field Medical and Rehabilitation Research Center aged 4 to 17 years was formed. All patients were in remission after the completion of antitumor treatment: 107 patients with hemoblastosis and 107 with solid tumors. The age of the participants ranged from 4.2 to 17.6 years, with an average age of 11.4 years. For a comprehensive assessment of the elemental status in children, hair and blood serum were used, measurements were carried out by mass spectrometry after mineralization of the samples. Results and Discussion. The results of the study of hair samples and blood serum showed that the elemental profile of patients after AT has both similar patterns and distinctive features depending on the histological type of tumor. Conclusions. Patients with solid tumors had a higher accumulation of toxic metals compared to samples taken from patients with tumors of the hematopoiesis organs. Nevertheless, no serious specific changes in elemental homeostasis were observed depending on the histological structure. The results obtained emphasize the importance of careful monitoring of homeostasis parameters to prevent the development of complications of antitumor therapy associated with elemental homeostasis.

We studied the immunomodulatory activity of L-lysine-α-oxidase (LO) from Trichoderma harzianum Rifai F180 to model endogenous colony-forming cells surface of the spleen of the mice of line F/SVA С 157В 1. LO shows immunomodulatory activity on models in vivo and in vitro.