[HYGIENIC ASSESSMENT OF NUTRITION AND INCIDENCE OF INDIVIDUAL DISEASES OF STUDENT'S SECONDARY PROFESSIONAL EDUCATION IN MODERN CONDITIONS].

The primary prevention of a significant number of diseases today is based on the principles of a healthy lifestyle which are the most important conditions for maintaining and strengthening the health of the population. At the same time, one of the main tasks is to optimize the nutritional status, preserve and improve the health of certain groups of the population and, above all, children and adolescents. The purpose of the work is a hygienic assessment of the characteristics of the nutritional status and nutritional health of young students and the scientific substantiation of recommendations for their optimization. It has been established that the insufficient level of knowledge of the basics of a healthy lifestyle and the existing shortcomings in the organization of nutrition of adolescents, as well as economic factors, lead to an inadequate nutritional status of students in secondary professional education, which is expressed in the low energy value of the diet, its imbalance and lack of diversity, as well as its low provision with macronutrients, vitamins and minerals. There is a significant increase in the incidence of diseases of the digestive system from junior to senior years, which allows us to consider college education as a risk factor for diseases of this class.

[The morbidity of medical personnel of mobile teams of emergency medical care].

The medical personnel of mobile teams of emergency medical care are exposed to factors of working environment that affect health state and results in development of occupational diseases. The purpose of study is to analyze morbidity of medical personnel of mobile teams of emergency medical care according data of temporary disability and results of medical check-ups. The analysis was made according information from certificates of incapacity for work and the final acts of periodic medical examinations for five-year period. The study established significant increase of rate and duration of primary and general morbidity with increase of age and length of service of workers, higher susceptibility to diseases of physicians as compared with paramedics and employees of pediatric teams and specialists of other clinical profiles. In the structure of morbidity according to results of medical examinations, diseases of the eye and its accessory apparatus, the circulatory system and the musculo-skeletal system prevailed.

[The characteristics of life-style of medical students].

The article considers the results of study of characteristics of lifestyle and behavioral risk factors of students of the medical university. MATERIALS AND METHODS: The object of the study was students of medical university. The survey was implemented in remote mode using the Google Forms. The relative values and their confidence intervals were calculated using the Wilson method. MS Excel 2019 and IBM SPSS Statistics 19 software were used to statistical process the research results. RESULTS: It is established that only every tenth student observed recommended duration of night sleep. The youths were about 1.7-4.6 times more likely to violate rules of personal hygiene as compared with girls. The unreasonable diet and low motor activity were more typical for girls. The prevalence of active tobacco smoking and nicotine use in dosage more than 0.1 mg/day among youths was 1.4 and 2.0 times higher than among girls, respectively (p<0.05). More than a half of respondents consume alcoholic beverages daily. At that, 44.12% of girls do not maintain sexual life, while among youths there were 1.5 times less of such individuals. The condoms during sexual contacts are obligatory used by 52.18% of youths that is 1.3 times more often than among girls. Almost three-quarters of medical students have insufficient alertness about their health and are characterized by irresponsible medical behavior. CONCLUSIONS: The gender differences in prevalence of lifestyle risk factors among medical students were revealed.

Biological and polymeric self-assembled hybrid systems: structure and properties of thylakoid/polyelectrolyte complexes.

A novel hybrid system composed of biological components and synthetic polymer, thylakoid/polycation complex, has been formed and studied. Effects of complex formation on the structure, electrostatics and functioning of thylakoid membranes have been examined. Thylakoids from bean leaves were used to form complexes with polycation polyallylamine hydrochloride (PAAH) in two systems: (i) thylakoid/polycation complexes formed in an aqueous bulk phase, and (ii) immobilized thylakoid/polycation planar complexes. Immobilized on a solid substrate surface, thylakoid/polycation complexes were prepared using layer-by-layer stepwise alternate adsorption technique, i.e., via the sequential alternate adsorption of thylakoids and polycation molecules. The morphology of built up structures was investigated by scanning electron microscopy. Light-induced electron transport in chloroplasts was studied by the electron paramagnetic resonance (EPR) method. Spin probe technique was employed to study the structural and electrostatic characteristics of thylakoid membranes. We have found that efficiency of light-induced electron transport in thylakoid membranes and membrane structure were not changed noticeably by PAAH binding to thylakoids in a wide range of PAAH concentrations. The data obtained indicate the physiologically-soft character of polycation interactions with thylakoid membranes and demonstrate effectiveness of interfacial self-assembly approach to fabrication of complex planar functional nanostructures from biological components and synthetic polymers.

Structural characterization of extracellular ribonuclease of Bacillus polymyxa: amino acid sequence determination and spatial structure prediction.

The primary structure of extracellular Bacillus polymyxa ribonuclease (RNase Bpo) was established by mass spectroscopy analysis and automatic Edman degradation of the individual peptides obtained from protein digestion with Glu-specific protease V8. RNase Bpo consists of 111 amino acid residues, with a relative molecular weight of 12 607. RNase Bpo is a close structural homolog of RNases of B. amyloliquefaciens (RNase Ba) and B. intermedius (RNase Bi), the similarity of their primary structures being 68%. Molecular modelling of the structure of the complex of RNase Bpo with substrate analog d(CGAC) was performed and a spatial model based on the known crystal structure of RNase Ba complex with the corresponding nucleotide was constructed using the methods of interactive computer graphics and energy minimization. The differences in the primary and tertiary structures of the enzymes were analyzed in order to understand the substrate specificity of Bacillus RNases.

A novel guanyl-preferable ribonuclease of Bacillus polymyxa: isolation and characterization of the enzyme.

Three forms of the extracellular alkaline ribonuclease of B. polymyxa (RNases Bpo I, Bpo II and Bpo III) were obtained in the homogeneous states. Relative molecular weights, N- and C-terminal amino acid sequences of the proteins were determined. The two higher-molecular weight forms of the enzyme (RNases Bpo I and Bpo III) were shown to be precursor molecules which differed from the mature B. polymyxa RNase (RNase Bpo II) by the presence of a extra twelve and six amino acid residues at the amino terminus, respectively. The study of catalytic properties of the enzyme elucidated that the extent of specificity of B. polymyxa RNase in respect to highpolymeric substrates is different from that of other natural Bacillus RNases. Amino acid composition of B. polymyxa RNase was established and structural similarity within family of Bacillus RNases is discussed. B. polymyxa RNase was shown to be inhibited by intracellular protein inhibitor of B. amyloliquefaciens RNase with the dissociation constant of 2.7 x 10(-12) M.

A novel Bacillus intermedius extracellular alkaline phosphatase: isolation, physico-chemical and catalytic characteristics.

A new alkaline phosphatase was obtained as homogeneous preparation from culture filtrate of the spore-forming Bacillus intermedius. B. intermedius phosphatase was shown to be monomer with molecular weight of 47 kDa. The enzyme possesses phosphomonoesterase and phosphodiesterase activities and exhibits a broad specificity towards a wide variety of substrates. The purified phosphatase had an optimum temperature of 50 degrees C, optimum pH of 9.5 and was stable until 60 degrees C at pH 8-10. The effect of divalent metal ions and thiol reagents on catalytic activity of the enzyme was studied.

Primary structure and catalytic properties of extracellular ribonuclease of Bacillus circulans.

A complete amino acid sequence of extracellular Bacillus circulans RNase was established and compared with a structure of B. amyloliquefaciens RNase. Gln15, Gly65 and Gln104 in B. amyloliquefaciens RNase were found to be replaced by Leu, Ala and Lys, respectively, in B. circulans RNase. Catalytic properties of B. circulans RNase were studied.

Two isoforms of Serratia marcescens nuclease. Crystallization and preliminary X-ray investigation of the enzyme.

Two isoforms of an extracellular endonuclease, nucleases Sm1 and Sm2, were purified from culture fluid of Serratia marcescens strain BIO MI by ligand-exchange chromatography on phosphocellulose and DEAE-Toyopearl 650S. The pI-values for nucleases Sm1 and Sm2 were found to be 7.1 and 6.7, respectively. The amino acid analysis and N-terminal amino acid sequencing of the proteins showed a significant degree of homology between the enzymes. The nuclease Sm1 has been crystallized from ammonium sulfate solution by the vapour diffusion technique. The crystals belong to the space group P2(1)2(1)2(1) with unit cell constants a = 69.0, b = 106.7, c = 74.8 A, contain two molecules in an asymmetric unit, packing density Vm = 2.3 A/Da, and diffract to at least 1.5 A resolution. The Pt- and UO2-derivatives of the protein were obtained. Preliminary X-ray investigation of nuclease Sm2 crystals was carried out.

Amino acid sequence determination of guanyl-specific ribonuclease Sa from Streptomyces aureofaciens.

Using automated Edman degradation of two nonfractionated peptide mixtures of tryptic and staphylococcal protease digests of the protein, the complete amino acid sequence of the guanyl-specific ribonuclease Sa from Streptomyces aureofaciens was established. Ribonuclease Sa contains 96 amino acid residues (Mr 10,566). A 50% sequence homology of ribonuclease Sa to the guanyl-specific ribonuclease St from S. erythreus was found.