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The review presents data on the importance of mitochondrial DNA in aging of cardiomocytes. The mechanisms of accumulation of mutations in mtDNA and reduction of its content, as well as the consequences of these phenomena in cardiomyocytes are described. The similarity of the aging processes of cardiomyocytes and skeletal muscle cells and comparison with the aging processes occurring in mononuclear cells of peripheral blood is indicated. The death of cardiomyocytes and skeletal muscle cells leads to the destruction of mutant forms of mtDNA, as a result of which the content of mutant forms of mtDNA, constantly increasing with age, does not exceed 1-2% of the total number of mtDNA molecules. In addition, the death of cardiomyocytes and myocytes is accompanied by the release of CpG-motive cells mtDNA, which can cause local and general inflammation in old age. It is concluded, that in the treatment of elderly patients it is desirable to take into account the degree of aging ("biological age”) of their myocardial and their presence of chronic myocarditis, for which appropriate diagnostic methods should be developed.

Stainless steels of austenite class 08–12Х18Н10Т have a high corrosion resistance, which stipulates for their wide application in various areas of industry. Technology of pipes production of the steels is rather specific and requires observation of some conditions. It was shown that temperature of a work-piece heating before deformation is an important parameter of the technology. It was noted that for the piercing of a steel work-piece with various chrome content, there is a rational temperature interval. Nonobservation of the temperature can lead to defects formation on internal pipe surface because of earlier destruction and opening of metal cavity during piercing. The choice of the rolling-out scheme has a direct effect on the work-piece forming in cross-sections. Results of hot rolling of Ø37×2,5 tube samples, manufactured of 08–12Х18Н10Т steel and carbon steel of grade 40 presented. The rolling was done at a laboratory mill. As a result of the experiment the lower limit of ovality of rolls grooves was specified for conditions of rolling of pipes from 08–12Х18Н10Т steels by 2-roll scheme. At the rolling with ovality B/H ≤1,07, defects appeared on the internal tube surface in the form of scratches caused by the mandrel. The rational range of ovality of grooves at multi-stand rolling can be from 1.08 to 1.15. According to criterion of groove overfilling by metal for steels 08–12Х18Н10Т, requirements were formed towards the groove width of the first stand of longitudinal rolling mill. The groove width must be larger than the sleeve diameter: for 3-roll scheme – at least by 2–3%, for 2-roll scheme – at least by 7.0–7.5%. Potential advantages of 3-roll scheme comparing with 2-roll scheme for rolling of 08–12Х18Н10Т steels were established as follows: lower probability of grooves overfilling by metal of the work-piece, absence of defects (scratches caused by mandrel), on the tube internal surface at minimal ovality level of 1.07, lower level of transverse pipe wall non-uniform thickness.

Аbstract. The current regulatory framework of the Ministry of Health and the Ministry of Defense of the Russian Federation on the regulation of the provision of medical assistance to military personnel affected by the infection caused by the SARS-CoV-2 coronavirus is considered. The state of the problem of information support for the provision of medical care to military personnel of this category is assessed. The developed methodology and the draft regulatory document for organizing the collection of medical information in the register of military personnel affected by the infection caused by the SARS-CoV-2 coronavirus are presented, and a regulation on this register is developed. The content, scope and algorithm of creating an information-analytical system for registering this pathology among military personnel, as well as the need to introduce new medical document management technologies into the medical service of the Armed Forces of Russia based on personified records of military personnel and the medical and psychological assistance provided to them, are substantiated. It is shown that for the smooth functioning of the register within the framework of a justified list of tasks, the presence of high-speed secure communication channels between the participating military units, institutions and medical service management bodies will be required. Consequently, the improvement of the information support system for managing the medical support of troops in peacetime and wartime is an important component of increasing the effectiveness of managing medical support for military.

Brown algae of the Fucaceae family, collected in the western segment of the Arctic, contain a large number of polyphenolic compounds—phlorotannins—with a unique chemical nature, macromolecular structure, and physicochemical properties, exhibiting bioactive properties. The peculiarity of the biopolymers’ properties and structure, which are an element of fundamental scientific research of the cycle, structure—functional nature—properties, determines the priority of the directions of use of polyphenols as effective biologically active pharmaceutical preparations. This work aims to develop methods for selective extraction of phlorotannins from the Arctic brown alga Fucus vesiculosus, characterization of physicochemical properties, and biological activity of these compounds. The efficiency of solid-phase extraction (SPE) on a hydrophobic sorbent with grafted hexadecyl groups was shown for fractionation of the polyphenolic extract: active fractions were obtained, characterized by a high content of polyphenols (yield of polyphenols up to 98% relative to the content of these components in algae) with mass-average molecular weights of 21.4–35.8 kDa and oligomeric components in the mass range 374–994 Da. The IR spectra of the fractions were characterized, and the tendency of phlorotannins to form aggregates at high concentrations of the extract was shown. During hydrodynamic studies, a strong polyelectrolyte swelling of polyphenols (PP) was noted. The obtained polyphenolic fractions differ in physicochemical characteristics (acid-base and redox properties) and antioxidant activity.

The extraction of polyphenol component of arctic brown algae of the Fucus vesiculosus type and the subsequent fractionation of the extract by column chromatography on a Sephadex LH-20 adsorbent are carried out. The obtained fractions are characterized by size-exclusion chromatography, HPLC with UV and mass spectrometric detection (HPLC–UV-MS), and matrix-assisted laser desorption/ionization mass spectrometry (MALDI–MS). Using the MALDI–MS method, the presence of oligomeric compounds containing up to 13 phloroglucin structural units is detected. Using HPLC–UV-MS, oligomeric compounds in the mass range 374–870 Da (trimers–octamers) are detected, and their ratio is estimated.

Arctic brown algae of the species Fucus vesiculosus are characterized by a high content of polyphenolic compounds - phlorotannins, exhibiting high biological activity. The aim of this study is to develop a methodology for the isolation and analysis of biologically active polyphenolic compounds from arctic brown algae. The proposed scheme for the isolation of polyphenols from Fucus vesiculosus brown algae is based on the principles of "green chemistry" and is carried out by sequential disassembly of the biomass of the plant object with the release of associated components (lipid-pigment complex, polysaccharides, mannitol) and maximum yield of polyphenol fraction. As a result of the experimental work, the optimal parameters for carrying out each stage of the proposed scheme were determined and a stepwise assessment of its effectiveness was carried out. The extractable fraction of polyphenols contains up to 67% of polyphenols relative to their content in the initial biomass, and the proportion of polyphenols in the fraction is up to 83%. A study of the phlorotannins fraction showed that its antioxidant activity is meaningful and it was 553±24 (mg of ascorbic acid/g extract). The polymolecular composition of the target fraction was investigated by the method of exclusion gel filtration chromatography, which showed the polymodal distribution, indicating the presence of several groups of components - low molecular weight and high molecular weight phlorotannins with masses ranging from thousands to hundreds of thousands of Daltons. The data obtained using chromatography-mass spectrometry and MALDI mass spectrometry make it possible to identify the presence of low molecular weight phlorotannins in the polyphenol fraction with masses from 250 to 1638 Da, which are close analogues in structure.

Introduction A screening of prostate cancer is an important problem of healthcare system worldwide. Aim To evaluate a possibility and efficiency of Belgian Malinois dogs sense of smell in diagnosis of prostate cancer. Materials and methods Urine samples from 176 men were assessed. Of these, 112 samples were taken from patients with biopsy-proven prostate cancer, and 64 from healthy young men. The study with two Belgian Malinois dogs consisted of two stages. The first stage was to train the dogs to distinguish the urine of patients with prostate cancer. A total of 66 urine samples were used at this stage (from 42 patients with prostate cancer and 24 healthy people). At the second detection stage, urine samples of patients with prostate cancer was identified. A total of 110 urine samples were evaluated (70 patients with prostate cancer and 40 healthy people). Results The first dog correctly identified 68 samples from patients with prostate cancer, and in 37 cases it indicated the absence of disease (sensitivity 97.1%, specificity 92.5%, accuracy 95.4%). The second animal correctly identified 69 and 39 samples, respectively (sensitivity 98.6%, specificity 97.5%, accuracy 98.2%). Conclusion A possibility of training dogs to identify patients with prostate cancer has been demonstrated. Further studies dedicated to the detection of volatile organic compounds in the urine using specialized analyzers of "electronic nose" type, as well as gas chromatography in combination with mass spectrometry, are of both scientific and practical interest.

This study presents results for the isolation, fractionation and characterization of Arctic brown algae polyphenols. New analytical data on the structure, functional nature and polymolecular properties of brown algal phlorotannins were obtained using modern analytical methods (size exclusion chromatography, liquid chromatography–mass spectrometry and fluorescence spectroscopy). The interrelation of radical scavenging activity and molecular weight of the algal polyphenolic components has also been established. Relatively high radical scavenging activity (776 ± 36 mg of ascorbic acid per g of extract) is observed for phlorotannin subfractions with average molecular weights from 8 to 18 kDa, enriched with phlorotannin oligomers with three to eight phloroglucinol units. Radical scavenging activity decreases with increasing molecular mass.

One of the most significant groups of compounds that determine the pharmacological significance of Arctic brown algae is the polyphenols, namely phlorotannins. Brown algae of the family Fucaceae, growing in the waters of the Arctic seas, accumulate a large number of polyphenolic compounds. The pharmacological significance of plant polyphenols is related to their structure; however, it is worth noting that the relationship between the molecular weight and the biological activity of brown algae phlorotannins is still not well understood. Thus, the aim of this work was the isolation and characterization of the polyphenol fraction of the Arctic brown algae Fucus vesiculosus with the following evaluation of the radical scavenging, bacteriostatic, fungistatic, and phagocytic activities. The highest radical scavenging activity (700–900 mg of ascorbic acid g−1 of extract) has fractions whose composition is characterized by the predominance of oligomeric phlorotannins containing from 3 to 8 structural units of phloroglucinol in the range of 374–994 Da. The polyphenol fractions obtained exhibit bacteriostatic effects in 45–85% of the studied pathogenic bacterial cultures. The fungistatic effect reaches a maximum of 35%. The test samples do not possess immunosuppressive properties and do not inhibit the phagocytic activity of neutrophilic granulocytes of human blood.

Introduction Pentacyclic triterpenoids (PCTs) are secondary plant metabolites. They are of exceptional interest as biologically active substances and raw materials for a wide range of medications. Thus, the development of a methodology for rapid screening of PCTs in plant biomass is an important task. Objective The goal of this work was to develop an approach for simultaneous screening and semi-quantitative determination of PCTs in plant tissues by liquid chromatography-tandem mass spectrometry with a precursor ion scan (PrecIS). Materials and methods Pressurised liquid extraction (PLE) with methanol was used for the isolation of PCTs from plant biomass. Screening and semi-quantitative determination of PCTs in the obtained extracts were carried out by reversed phase high-performance liquid chromatography-tandem mass spectrometry in a PrecIS mode. Results The product ion at m/z 95 with collision energy of 40 V was used as a diagnostic ion to identify PCTs by the PrecIS mode. In plant materials, 26 PCTs and their derivatives, such as PCTs esters and glycosides, were detected and identified. Calculation of the relative response factor for nine available PCTs showed that using a betulin calibration curve allows us to estimate the semi-quantitative content of PCTs and their derivatives in plant PLE extracts. Conclusion The developed approach can be applied for simultaneous untargeted screening and semi-quantitative determination of PCTs and their derivatives in various plants at sub-parts per million levels.

The Nucleodur HILIC zwitterionic stationary phase was characterized by linear solvation energy relationship (LSER) analysis in the supercritical fluid chromatography mode. It was shown that the main contribution to retention is made by hydrogen bonding interactions.

One of the greatest statesmen of the Russian Empire in the late XVIII century, count Aleksei Ivanovich Vasil’ev, is one of the few personalities who have left their mark in different fields - Finance and health care. Being a financier by education and the main duration of activity and having done much for formation of harmonious budgetary policy of Russia, he was able to reconstruct system of health care and medical education, to turn the medical and surgical schools located in St. Petersburg into the Academy which became the basis of medical education in Russia

The fatty acid composition of arctic brown algae was studied using supercritical (SC) fluid extraction. A method for fractionating the SC extract based on the differences in the solubility of its components (fatty acids, polyphenols) was proposed. The composition and biological activity of the fractions were studied.

Enterosorption properties of algae fiber were studied. Determination of the thermodynamic characteristics of heavy metal sorption showed that the process is endothermic with the prevalence of chemisorption interactions. Algae fiber exhibits high sorption capacity for heavy metals and pathogenic microorganisms.

A scheme for producing cellulose from the artic brown algae Fucus vesiculosus and Laminaria digitata was proposed. The physicochemical and structural features of the cellulose samples were studied and compared with those of celluloses from higher plants. Cellulose from Fucus vesiculosus was found primarily in the Iα-form; from Laminaria digitata, the Iα- and Iβ-forms. The studied samples were assumed to contain slightly crystalline cellulose with a structure similar to that of cellulose II. Its content was typically greatest in F. vesiculosus (58%).

Natural pentacyclic triterpenes were extracted from birch bark with subcritical solvents. The influence of the solvent nature, temperature, and the number of extraction cycles on the efficiency of the process was studied. Using methanol at 100 °С provides the highest tri-terpene extraction rate. Bark extracts prepared using various solvents were analyzed for chemical composition and antioxidant activity.

A screening of prostate cancer is an important problem of healthcare system worldwide.To evaluate a possibility and efficiency of Belgian Malinois dogs sense of smell in diagnosis of prostate cancer.Urine samples from 176 men were assessed. Of these, 112 samples were taken from patients with biopsy-proven prostate cancer, and 64 from healthy young men. The study with two Belgian Malinois dogs consisted of two stages. The first stage was to train the dogs to distinguish the urine of patients with prostate cancer. A total of 66 urine samples were used at this stage (from 42 patients with prostate cancer and 24 healthy people). At the second detection stage, urine samples of patients with prostate cancer was identified. A total of 110 urine samples were evaluated (70 patients with prostate cancer and 40 healthy people).The first dog correctly identified 68 samples from patients with prostate cancer, and in 37 cases it indicated the absence of disease (sensitivity 97.1%, specificity 92.5%, accuracy 95.4%). The second animal correctly identified 69 and 39 samples, respectively (sensitivity 98.6%, specificity 97.5%, accuracy 98.2%).A possibility of training dogs to identify patients with prostate cancer has been demonstrated. Further studies dedicated to the detection of volatile organic compounds in the urine using specialized analyzers of "electronic nose" type, as well as gas chromatography in combination with mass spectrometry, are of both scientific and practical interest.

A mathematical model of wheel-rail interaction for unworn profiles in the final-element modeling environment under different movement conditions, i.e. with the addition of additional torque and frictional forces, has been developed and tested in the article. Thus, the movement of rolling stock in the mode of braking (related to all cars and locomotives) and gaining traction (related to locomotives) is simulated. A significant influence of friction forces in the contact zone and additional torque on the stress-strain state during the interaction of the wheel and the rail are shown. The data obtained are additional refinements of one of the important factors in testing the durability of the material from which the rails are made – the loading of the samples and load application frequency. The work also approximated the results to maximize compressing and stretching stresses on the rail surface not only in a few variants of the studied original data. With the help of approximation, it is possible to study the stress state of the “wheel – rail” system at any point in a given range of vertical forces and additional torque.

Non-symmetric derivatives of actinocin containing fragments of benzo-18-crown-6 and dimethylaminopropylamine (with the crown ether group separated from the heterocyclic chromophore by β-alanine moiety) have been prepared as models of actinomycin D.

Derivatives of benzoic and cinnamic acids are secondary metabolites of plants, widely distributed in nature and possessing biological activity. Supercritical fluid chromatography (SFC) is shown to provide a high performance separation of nine most important representatives of this class of compounds with selectivity, dramatically different from the reversed-phase high-performance liquid chromatography. The retention and chromatographic separation parameters of analytes for four stationary phases of different nature are compared and the effect of supercritical fluid parameters and the composition of the mobile phase onto the chromatographic separation are analyzed. The optimal separation is found to be achieved when using a silica-based sorbent with 2-ethylpyridinium linked groups. The proposed approach for determination of the above-mentioned compounds is based on the combination of chromatographic separation with multiwavelength spectrophotometric detection and provides the detection limits in the range of 13.0–51.3 μg/L and the analysis duration about 2.5 min. The approach is successfully tested on real objects, such as different kinds of wine.

Anniversary of the science regulatory body of the S.M.Kirov Military medical academy. In the nineteenth century the Military-medical scientific committee was responsible for organization of scientific activity in the system of medical service of the Armed Forces; in the soviet period - the Military-scientific committee of the Main military-medical authority (since 1930) and scientific department of the S.M.Kirov Military medical academy (since 1931). In 1931-1936 and in 2010-2014 the Military-scientific committee of the Main military- medical authority was dissolved, and in 1936-1940 and in 2014-2015 conducted a supernumerary activity, during these periods the scientific department of the S.MKirov Military medical academy was responsible for coordination of scientific work in the Armed Forces. An experience of organization of the scientific regulatory bodies brought positive results and allows developing medical science further in the interests of the Army and the Navy.

Forum of military physicians of Asia Pacific region. Authors proviae a report about the 3rd Military medical Asia Pacific congress, which was held in August 2016 in Saint Petersburg under the authority of the International military medical committee. Within the frame of the congress was held regional workshop, in the course of which was heard a report of the Thailand representative, requests of observer states for the entry. The country, which will hold the 4th Military medical Asia Pacific congress, is Iran. On the last day of the congress delegates visited the finals of the Military-medical race of the military physicians profession skill competition withinThe international army games-2016.

The article describes the experience of reconstructive and restorative operative treatment of patients with, defects of the skin of the fingers at the daily surgical hospital. It is shown that surgeons applying standard instruments and having additional training in hand surgery, using a technique non -free skin plastic flap on a temporary pedicle and using inpatient technology, get cosmetic and functional results compared to-those of treatment in hospitals. Cited in -the article data on the direct and separate treatment outcomes, quility of life of patients, the estimated non-specfic and organ-specific method, clearly show that non-free skin plastic flap on a temporary pedicle - a reliable and effective method of restoration of the skin fingers defects which can be accompanied wit the use of resource-saving technologies in health care.

Four polar stationary phases (ethylene-bridged hybrid silica, cyanopropyl, 2-ethylpyridine, and zwitterionic sulfobetaine) have been characterized in supercritical fluid chromatography (SFC) by linear free energy relationships (LFER) method with an extended set of Abraham's descriptors. Temperature (25–55 °C) and pressure (110–180 bar) effects on analyte retention, separation selectivity and LFER-coefficients of chromatographic systems have been studied using the 89 test compounds of various chemical classes and carbon dioxide – methanol (9:1 v/v) binary solvent as a mobile phase. It was found that for the selected stationary phases temperature and pressure had only moderate effects on selectivity. The retention times of all analytes decrease, as can be expected, if the pressure rises at the isothermal conditions due to the increase of the fluid density and its eluting power. The effect of temperature on retention is complicated and depends both on the chemical class of analyzed compounds and the stationary phase type. Temperature and pressure variations lead to small changes in the LFER-coefficients, and general trends observed do not depend much on the stationary phase type. It may be difficult to interpret the LFER-analysis results because of the evident, more significant chromatographic phenomena.

Pentacyclic triterpenoids (PCTs) possess high biological activity, including antitumor, anti-inflammatory, antiviral and hepatoprotective properties and are widespread in a plant biomass. Due to significant differences in polarity and other physicochemical properties, the simultaneous determination of different classes of PCTs by the methods of reversed phase liquid chromatography is difficult. In the present study, we proposed a new approach to chromatographic separation of such compounds based on the use of a stationary phase with a mixed retention mechanism combining hydrophobic, weak anion exchange and hydrophilic interactions. The use of the Acclaim Mixed-Mode WAX-1 column and tuning the selectivity by changing the contributions of different types of analyte–stationary phase interactions allowed the separation of 10 PCTs (betulin, erythrodiol, uvaol, friedelin, lupeol, β-amyrin, α-amyrin, betulinic, oleanolic and ursolic acids) belonging to four different classes (monools, diols, ketones and triterpenic acids) during 7.5 min in isocratic elution mode. The combination of this approach with atmospheric pressure chemical ionization tandem mass spectrometric detection and pressurized liquid extraction of analytes with methanol allowed to develop a rapid, accurate and highly sensitive method for analyzing PCTs in plant tissues with a total duration of the analytical cycle (including sample preparation steps) of not more than 40 min. It provides the detection limits in plant biomass extracts of 3–12 µg L–1 (44 µg L–1 for friedelin). The developed method was validated and successfully tested in the analyses of real birch bark and lingonberry peels.

A group G is m-rigid if there exists a normal series of the form G = G1 > G2 > . . . > Gm > Gm+1 = 1 in which every factor Gi/Gi+1 is an Abelian group and is torsion-free as a (right) Z[G/Gi]-module. A rigid group is one that is m-rigid for some m. The specified series is determined by a given rigid group uniquely; so it consists of characteristic subgroups and is called a rigid series; the solvability length of a group is exactly m. A rigid group G is divisible if all Gi/Gi+1 are divisible modules over Z[G/Gi]. The rings Z[G/Gi] satisfy the Ore condition, and Q(G/Gi) denote the corresponding (right) division rings. Thus, for a divisible rigid group G, the factor Gi/Gi+1 can be treated as a (right) vector space over Q(G/Gi). We describe the group of all automorphisms of a divisible rigid group, and then a group of normal automorphisms. An automorphism is normal if it keeps all normal subgroups of the given group fixed.

Methods for measuring the resistivity of materials during elastic and elastoplastic interactions of a current-conducting indenter and a studied sample are described. Analytical methods that describe the dependences of the contact ohmic resistance on the pressure force and the contact stiffness are proposed. The considered models are experimentally tested with a NanoScan scanning nanohardness tester using indenters made of boron-doped diamond single crystals.

A case of elution order inversion caused by cosolvent percentage change in supercritical fluid chromatography was observed and investigated in some detail. Z- and E-isomers of phenylisobutylketone oxime experience an elution order reversal on most columns if the mobile phase consists of CO2 and alcohol. At lower percentages of alcohol Z-oxime is retained less, somewhere at 2-5% coelution occurs and at larger cosolvent volume elution order reverses - Z-oxime is eluted later than E-oxime. We suppose inversion with CO2-ROH phases happens due to a shift in balance between two main interactions governing retention. At low ROH percentages stationary phase surface is only slightly covered by ROH molecules so oximes primarily interact with adsorption sites via hydrogen bond formation. Due to intramolecular sterical hindrance Z-oxime is less able to form hydrogen bonds and consequently is eluted first. At higher percentages alcohols occupy most of strong hydrogen bonding sites on silica surface thus leaving non-specific electrostatic interactions predominantly responsible for Z/E selectivity. Z-oxime has a much larger dipole moment than E-oxime and at these conditions it is eluted later. Additional experimental data with CO2-CH3CN, hexane-iPrOH and CHF3-ROH mobile phases supporting this explanation are presented.

Microalloying with boron (up to 0.005%) has a considerable influence on the hardenability of steel. Four alloying systems with complete and partial replacement of molybdenum by microadditions of boron are studied. The resulting mechanical properties are satisfactory for high-strength pipe corresponding to strength groups from N80 (type Q) to Q135, according to the API 5CT, ISO 11960, and GOST R 53366 standards. The reversible tempering brittleness of Nb-B steel and Mo-B steel is considered. Overall, the strength and impact strength of Mo-B steel are greater than for steel without molybdenum.

A probabilistic-statistical parameterization of time series characterizing geological and climatic processes allows determining some regularities by an autocorrelation analysis of signals which differ in nature. The use of the autocorrelation method for analyzing data related to solar and tectonic activity and characterizing the level of stratospheric ozone (total ozone content), hydrothermal regimes (De Martonne aridity index), and wood structure (maximum density of annual rings) allows us to find regularities in time series of various natural processes. Data on the maximum density of Siberian larch trees growing in the Altai Mountains made it possible to calculate the past changes in total ozone content and the aridity index in the Altai Mountains from 1900 to 2014 based on some similarities in the series and a separation of a dendrochronological signal into its main components.

A number of actinocin amides containing residues of aza-15-crown-5 and aza-18-crown-6 where crown fragments were separated from the heterocyclic chromophore by the residues of ω-amino acids were obtained as actinomycin D models.

An important problem of molecular biophysics is the influence of pH and ionic strength of a solution on chemical structures and charge of biologically active substances. By means of pH titration and Raman spectroscopy methods, the influence of solution acidity on structural changes of actinocin derivatives was investigated, analogues to antitumor antibiotic actinomycin D. It has been shown that these ligands have different values of cation charges in neutral solutions. From analysis of Raman spectra, it was concluded that protonation of nitrogen atom and amino group of the phenoxazone ring starts only at pH

Biochemist Fedor Aronovich LeviN (1869-1940) graduated with honours from the S.M.Kirov Military Medical Academy in St. Petersburg in 1891 where he had received a fundamental knowledge from A.P.Dianin and I.P.Pavlov, and then he immigrated to the US. More than three and a half decades of his successful research at the Rockefeller Institute for Medical Research contributed to the foundation of the doctrine of nucleic acids. Scientists, who continued to research nucleic acids, were awarded the Nobel Prize, but Levin and his contribution were forgotten. The authors of the given article didn't found any source in Russian about this prominent biochemist of the 20th century and member of the Russian scientific school. The purpose of the article is to acquaint the reader with a scientific biography of the scientist. who became, without exaggeration, one of the founders of modern genetics.

Achalasia is a progressive oesophageal motility disorder of unstudied aetiology involving the smooth muscle layer of the oesophagus. Insufficient knowledge of the pathogenesis of achalasia and the lack of clear treatment approaches has led to an increase of advanced disease forms. Common clinical manifestations of the disease are: incomplete LES relaxation, non-specific initial manifestations and as a result late medical seeking. Occurrence of achalasia cardiae is significantly low, therefore it is important to analyse the available clinical data. The article presents an experience of treatment of 30 patients over the last 16 years of observation. The average age of patients was 50, 5 years; insignificant male predominance is noted. III or IV disease state was diagnosed in 86.7% of patients; this diagnosis was confirmed by esophagogastroduodenoscopy. In the group of 24 patients who underwent attempted endoscopic dilatation of the cardiae, most of the included patients with stage II and III disease. Immediate good and satisfactory results of endoscopic treatment were obtained in 20 patients (83.3%), in 4 cases (16.7%) developed recurrent disease.

Complexes of DNA with benzocrown derivatives of actinocin were studied by viscometry and dynamic birefringence. Changes in the macromolecular structure of DNA caused by complex formation were determined. Models of DNA binding to the studied compounds were suggested on the basis of data obtained. The intercalation of actinocin chromophore of benzocrown derivatives of actinocin was shown to occur only when benzocrown groups were bound to the chromophore via the glycine spacer. A change of the distance between the crown group and the chromophore prevented ligand intercalation. Increase of the ionic strength resulted in appearance of a new, nonintercalative binding mode for crown-containing compounds determined by interaction of the crown groups with DNA.

Percutaneous endoscopic gastrostomy for provision of the long-term enteral nutrition is well established in clinical practice because unlike from traditional gastrostomy and jejunostomy allowed to avoid many complications. The technique is used for enteral tube feeding in the absence of real positive predictive recovery of consciousness and swallowing function. During presented study from 387 patients with a gastrostomy imposed by percutaneous endoscopic technique, observed only 1,8% of suppurative complications and in 1% of cases - uncontrolled removal of the tube by the patient. Our experience allows us to recommend this technique for wide implementation in practice of medical institutions in case when it is necessity in enteral feeding more than 3 weeks of patients with impaired

Training of scientific and scientific-pedagogical staff is one of the most important tasks of any high school. The problem of staff training arose in the Kirov Military Medical (Medical Surgical) Academy before its official foundation. In 1741 first scholars were sent abroad for the preparation of theses. The scholars were supposed to return to the hospital schools for teaching activity. Since 1802 scholars have defended their theses in the Academy. In 1858 special medical institute, the prototype of the Institute for postgraduate military studies was established. Many outstanding scientists studied in the Academy and brought name of the Academy into repute. At the present time, the Institute of postgraduate military studies (postgraduate) of the Kirov Military Medical Academy continues to train scientific staff. The Institute of postgraduate military studies remains one of the most successful institutes in Russia.

The article presents an analysis of long-term experience of treatment of 128 patients with benign esophagus and esophageal anastomosis strictures in Kirov Military Medical Academy. This significant data included all possible variations of scarry esophageal strictures according their etiology, localization and the extension. The wide range of methods, which involved the different variants of bouginage, balloon dilation, stenting, electrosurgical dissection and resection of the stomach, were applied in treatment of the patients. The analysis of immediate and long-term results allowed detecting the criteria of choice and indication for use of the methods or their combination. Practical recommendations reflect the strategy of each variant of treatment and have the specific character. Possible complications and negative results of irrational application of different methods were presented. The immediate and long-term results gave evidence of the successful treatment of the patients with scarry esophagus and esophageal anastomosis strictures.

An algorithm for computer simulation of images obtained by magnetic force microscopy (MFM) is suggested. It is based on the Brown formalism and takes into account the shapes and the magnetic properties of the MFM tip and sample studied. The robustness and efficiency of the algorithm are tested by simulating the MFM image of a point magnetic dipole for the case where the tip is approximated by a nonmagnetic truncated cone covered by a thin uniformly magnetized layer. From the computer simulation of the MFM images of the dipole, the optimum parameters of the MFM probe are obtained.

We have developed the atomic force microscope (AFM) for in situ observation of SiO 2 etching in the HF aqueous solution. This work is devoted to the AFM investigation of etching of the SiO 2 surface layer modified by high-dose Fe + ion bombardment. Such samples have a two-phase nanostructure (SiO 2 containing buried Fe nanoparticles). Formation and dissociation of nanorelief during etching was observed in situ with AFM. The computer animation of this phenomenon was made with morphing of the experimental AFM images. The additional in situ registration of the optical absorption of Fe nanoparticles during etching, ex situ AFM and ferromagnetic resonance measurements enable us to propose that observed morphology transformation takes place because the etching rate of Fe nanoparticles is much higher than the SiO 2 etching rate. This etching mechanism was used for computer simulation of the AFM image transformation during etching of the model samples with buried nanoparticles. Good correlation of simulated and experimental AFM images and the corresponding surface roughness parameters vs. etching time confirms that this structural model and the mechanism of selective etching are correct.