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Olfactory disorders is one of the first symptoms of diseases from various departments of medicine (otorhinolaryngology, psychology, neurology, etc.). Based on international clinical recommendations, olfactory tests are the gold standard for the diagnosis of olfactory disorders. There are many different psychophysical tests: UPSIT (USA, Pennsylvania), Sniffin' Sticks test (Germany), BAST-24 (Spain), etc. Currently, there is an acute shortage of olfactory tests available for clinical practice In Russia. This problem is related to the fact that there are no olfactory tests registered as medical devices on the territory of the Russian Federation. Also, a significant limitation is the unrecognizability of odors by the population of our country, which include foreign analogues (licorice, anise, turpentine, etc.)., Objective: To develop and validate the national olfactory test on healthy volunteers., Material and Methods: The development and validation of the olfactory test included several stages. First, the development of an olfactory test was carried out, the selection of aromas to assess the threshold and identification ability of olfaction. 25 dilutions of n -butanol were used for the assessment of the threshold olfactory ability. For the stage of assessing the identification ability of the sense of smell, in our previous study, an assessment of the recognition of odor names in the territory of the Russian Federation was carried out. A total of 3.000 people from 8 federal districts of the Russian Federation were interviewed. During the development of the test, 20 names of flavors with the highest rating were used. By the 8 th , the selection of monocomponent substances was carried out. Commercially available certified food and perfume flavorings have been used for fragrances whose equivalent in the test cannot be a monocomponent substance. A group of 25 healthy volunteers selected a flavor or a monocomponent for each of the 20 positions. To carry out the identification stage of testing, a booklet was developed with answer options for each fragrance, including 80 images associated with the smell. A methodology for conducting diagnostics has been created. Next, the validation of the developed olfactory test was carried out on 150 healthy volunteers. The study included an assessment of the threshold and identification ability of the sense of smell using the developed test and conducting a comparative analysis with a set of flavors and descriptors corresponding to the Sniffin' Sticks test., Results: The developed test includes: 2 panels - panel 1 to assess the threshold ability of smell, panel 2 to assess the identification ability of smell, a booklet with 80 images and captions to them. The norms of threshold and identification olfactory abilities were also determined in the developed test. The domestic test was validated against the relative foreign Sniffin' Sticks test. Spearman's correlation between the accuracy values of the domestic test (17-20; 85.00-100.00%) and the values of the foreign test (11-16; 68.75-100.00%) did not reveal statistically significant differences ( rs =0.065, p =0.432), which confirms the equally effective assessment of olfactory ability by the domestic olfactory test in comparison with its foreign counterpart., Conclusion: In this work, a methodology for the use of Russian olfactory test was developed and validated on healthy volunteers. The features of the developed test are an assessment of the threshold and identification ability of smell, an adapted set of odors for the Russian population, the use of paper blotters when applying flavor and visual images of descriptors. Despite the wide variety of psychophysical tests, this problem requires further study and comparative analysis of olfactory tests available In Russia and foreign analogues in order to obtain a universal and effective diagnostic method for the populations of our country., This work was supported by the Russian Foundation for Basic Research (Project No. 24-25-00415).

Three enzymes with milk-clotting activity have been isolated from the fruiting bodies of Pleurotus ostreatus (Fr.) Kumm.) by (NH4)2SO4 precipitation, gel chromatography on Sephadex G75, and ion exchange chromatography on carboxymethylcellulose (CMC). Isoelectric points of the enzymes, as determined by isoelectrofocusing, equaled 4.2, 6.7, and 8.8. Inhibition analysis showed that the enzymes with isoelectric points of 4.2 and 6.7 belong to the class of metal-dependent proteinases, while the enzyme with the isoelectric point of 8.8 belongs to the serine protease class.

On the basis of previously published experimental data, the catalytic cycle of Escherichia coli galactosidase has been reconstructed. The enzyme plays a key role in the transcription regulation of lac operon. Using the proposed scheme, we have built a kinetic model that takes into account the reactions of hydrolysis, isomerization as well as galactosylation. Using the experimental data and optimization algorithms, all parameters of the model have been estimated. On the basis of the model, the features of beta-galactosidase functioning have been predicted in a wide range of conditions.

A Rapid Equilibrium Random Bi Ter mechanism of formation of two dead-end complexes was proposed to describe the experimental data on the functioning of E. coli isocitrate dehydrogenase (IDH). A kinetic model for the enzyme functioning was constructed, which assumes that it is regulated through reversible phosphorylation by its kinase/phosphatase, which in turn is regulated by IDH substrates and central metabolites such as pyruvate (Pyr), 3-phosphoglycerate (3-PG), and AMP. It was shown using the model that increasing the concentration of these effectors results in an increase of the active part of IDH, thus leading to an increase in the Krebs cycle flux. We predict that the ratio of the phosphorylated and free forms of IDH (IDHP/IDH) is more sensitive to AMP, NADPH, and isocitrate concentrations than to Pyr and 3-PG. The model allows a realistic prediction of changes in the IDHP/IDH ratio, which would occur under changes of biosynthetic and energetic loading of the E. coli cell.

Based on the available experimental data, we developed a kinetic model of the catalytic cycle of imidazologlycerol-phosphate synthetase from Escherichia coli accounting for the synthetase and glutaminase activities of the enzyme. The rate equations describing synthetase and glutaminase activities of imidazologlycerol-phosphate synthetase were derived from this catalytic cycle. Using the literature data, we evaluated all kinetic parameters of the rate equations characterizing individually synthetase and glutaminase activities as well as the contribution of each activity depending on concentration of the substrates, products, and effectors. As shown, in the presence of 5 -phosphoribosylformimino-5-aminoimidazolo-4-carboxamideribonucleotide (ProFAR) and imidazologlycerol phosphate (IGP) glutaminase activity dominates over synthetase activity at sufficiently low concentrations of 5 -phosphoribulosylformimino-5-aminoimidazolo-4-carboxamideribonucleotide (PRFAR). Increased PRFAR concentrations resulted in decreased contribution of glutaminase activity and, consequently, increased the contribution of synthetase activity in the enzyme functioning.

A kinetic model of the cytochrome bf complex was developed on the assumption that the Q-cycle operates. The bf complex was considered as a membrane enzyme catalyzing the electron transfer from plastoquinol to plastocyanine, which is coupled with proton translocation from the chloroplast stroma to the thylakoid lumen. The dependence of the electron transfer rates on the value of the transmembrane electric potential was taken into account. The model was applied to describe the experimental data on the flash-induced turnover of cytochromes b, plastocyanine, and the kinetics of proton deposition in the thylakoid lumen. The estimation of model parameters was performed.

A kinetic model was developed, which describing the system of generation and consumption of the transmembrane electrochemical proton potential delta mu H+ in primary photosynthetic processes. The model describes the catalytic cycles of photosystems I and II and the cytochrome b/f complex, as well as the ATP synthesis and passive leakage of H+, K+ [symbol: see text] Cl- ions through the thylakoid membrane. The dependence of the electron transfer rates on the value of transmembrane electric potential was taken into account. The model was applied to describe the experimental data on the registration of the fast phase of fluorescence induction. The model gives a realistic description of the fast phase of induction curves at different light intensities (from high to low).

The basic mechanisms of kinetic regulation of photosynthetic processes are considered, which provide a strict light regulation of electron transfer in photosynthetic reaction centers and a more flexible regulation at the level of interaction of photosystems, transmembrane ion fluxes and coupling with dark reactions of the Calvin cycle. A generalized model was developed, which integrates the modern knowledge about photosynthetic processes of higher plants. The general principles of multilevel regulation in photosynthetic systems are discussed.

Experimental measurements of intracellular pH kinetics detect intracellular pH (pHin) rhythms with a period about an hour and an amplitude comparable with the standard deviation of pHin in cell population. It was shown that pHin oscillations were probably to affect the experimental pH-distribution pattern. The pH-distribution of the population at normal physiological state is usually close to the normal pattern. The time-course of the pHin value for the cell population was shown to have a pattern of a kind of beatings to get the normal pH-distribution. Distributions of several "beating"--functions were used to approximate an experimental pH-distribution of immunocompetent cell population.

The intracellular pH distribution of peripheral cattle lymphocytes has been studied in normal state and at six stages of the development of bovine leukosis by the dye microfluorimetry of single cells. It has been shown that the increase of mean intracellular pH value occurs as well some distribution parameters, such as pH range and asymmetry change during the disease process. Probable reasons responsible for the observed modification of the distribution pattern are discussed.

Some problems of establishing the complex of diagnostic investigations based on the use of medical instrumentation in outpatient clinics with 50 000 and more population being served are discussed. The methodology to evaluate informative signs according to every diagnostic examination is presented. Computational relationships for quantitative evaluation of informative signs are given as well as an algorithm of generalized examination results reporting.