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Pseudomonas phage MD8 is a temperate phage isolated from the freshwater lake Baikal. The organisation of the MD8 genome resembles the genomes of lambdoid bacteriophages. However, MD8 gene and protein sequences have little in common with classified representatives of lambda-like phages. Analysis of phage genomes revealed a group of other Pseudomonas phages related to phage MD8 and the genomic layout of MD8-like phages indicated extensive gene exchange involving even the most conservative proteins and leading to a high degree of genomic mosaicism. Multiple horizontal transfers and mosaicism of the genome of MD8, related phages and other λ-like phages raise questions about the principles of taxonomic classification of the representatives of this voluminous phage group. Comparison and analysis of various bioinformatic approaches applied to λ-like phage genomes demonstrated different efficiency and contradictory results in the estimation of genomic similarity and relatedness. However, we were able to make suggestions for the possible origin of the MD8 genome and the basic principles for the taxonomic classification of lambdoid phages. The group comprising 26 MD8-related phages was proposed to classify as two close genera belonging to a big family of λ-like phages.

Micromycetes are known to secrete numerous enzymes of biotechnological and medical potential. Fibrinolytic protease-activator of protein C (PAPC) of blood plasma from micromycete Aspergillus ochraceus VKM-F4104D was obtained in recombinant form utilising the bacterial expression system. This enzyme, which belongs to the proteinase-K-like proteases, is similar to the proteases encoded in the genomes of Aspergillus fumigatus ATCC MYA-4609, A. oryzae ATCC 42149 and A. flavus 28. Mature PAPC-4104 is 282 amino acids long, preceded by the 101-amino acid propeptide necessary for proper folding and maturation. The recombinant protease was identical to the native enzyme from micromycete in terms of its biological properties, including an ability to hydrolyse substrates of activated protein C (pGlu-Pro-Arg-pNA) and factor Xa (Z-D-Arg-Gly-Arg-pNA) in conjugant reactions with human blood plasma. Therefore, recombinant PAPC-4104 can potentially be used in medicine, veterinary science, diagnostics, and other applications.

Statins are the main class of drugs that are used to treat patients with hyperlipidemia and atherosclerosis. Over the past decades, dozens of randomized clinical trials with this group of drugs have been conducted. Their results showed a significant reduction in cardiovascular and overall mortality, regardless of gender, age, baseline cholesterol levels. Currently, 6 drugs of this class are registered in the Russian Federation: Atorvastatin, Lovastatin, Simvastatin, Pravastatin, Rosuvastatin and Fluvastatin.

The article studies the effect of activated carbon with sorption capacity saturated by manganese (II) and chromium (III) ions on the vital activity of organisms and systems. Desorption of the toxic component from the surface of the sorbent occurs in accordance with the sorption equilibrium constant. This can produce a polluting effect on the water passing through carbon, on the activity of the soil microorganisms, and on the areas allocated for storage of used sorbents. The article presents new data on the effect of extracts of activated carbon saturated with manganese (II) and chromium (III) salts on the parameters of the blood of laboratory mice and the vital activity of soil microorganisms. The authors synthesized activated carbons with manganese (II) and chromium (III) ions adsorbed on the surface. The activity of alanine aminotransferase and aspartate aminotransferase and the content of total protein, albumin, urea, medium molecular weight molecules, malonic dialdehyde, and products of protein oxidation were identified in the blood of mice after oral administration of extracts of sorbents. After contact with the soil, the effect of adsorbed metals on its catalase and phosphatase activity was detected, as well as changes in the number and composition of soil microorganisms. The study demonstrated that carbons, with a sorption capacity filled by metal ions, affected some of the studied parameters. The authors recorded an increase in the number of products of lipid peroxidation and in urea content after the administration of sorbent suspensions; at the same time, a decrease in the total protein content in the blood of mice was noted. Manganese-adsorbed by carbon also causes a decrease in the number of oligonitrophilic, oligotrophic, and amylolytic groups of soil microorganisms, as well as a simplification of the generic structure of soil micromycetes due to the disappearance of rare genera of Miceliasterilia, Myrothecium.

In review presents the patological effects of aldosterone, clinical pharmacology of aldosterone antagonists and their role in countering the development of cardiovascular diseases are highlighted. The results of clinical studies have demonstrated high clinical efficacy and safety of spironolactone and eplerenone in a wide range of cardiovascular risk. However, the potential adverse drug reactions associated with these drugs limit their use in some categories of patients. However, adequate monitoring of these reactions, including hyperkalemia and acute kidney injury, can be avoided. In situations where there are indications for the use of spironolactone or eplerenone, the latter is the drug of choice due to the lower risk of gender adverse reactions. The frequency of other adverse drug reactions, in particular hyperkalemia, spironolactone and eplerenone are comparable.

Aim. To find antihypoxic properties in complex compounds of some divalent metals on the model of acute hypoxia with hypercapnia. Methods. In the experiments on mice in acute hypoxia with hypercapnia (AH+Hc), the protective effect of 6 new complex compounds was studied in comparison with the effectiveness of reference antihypoxants. Substances were injected intraperitoneally 60 min before acute hypoxia with hypercapnia in doses of 25 and 50 mg/kg. Antihypoxic effect was compared with their ability to change the rectal temperature. Results. The most active substance πQ-2116 with Nickel as a complexing metal was established. Mice resistance to acute hypoxia with hypercapnia at a dose of 25 mg/kg was increased to 89.5%, at a dose of 50 mg/kg – to 165.8%. The effect was accompanied by serious hypothermia, reaching 28.5 °C. Antihypoxic activity of the substance πQ-2116 is comparable with reference substance πQ-1983 and greater than the effect of aminothiol antihypoxants – Amtizole and Sunazole.

Bioinformatic analysis demonstrates the presence of SGNH-domain in the receptor-binding tail spike protein of Pectobacterium bacteriophage PP16. This protein has a modular structure, and the enzymatic part of the tail spike is a subject to horizontal transfer. The experiments with the recombinant protein indicated that the C-part of the tail spike is insufficient for binding with the receptor.

The electronic properties of single-layer graphene doped with nitrogen and boron atoms with varying doping consen-trations and configurations have been investigated via firs-principles density functional theory calculation. It is found that the electronic properties of such systems are strongly influenced by the concentration of dopants and their arrangement in the graphene crystal lattice. The effects of doping of a graphene monolayer on its electronic spectrum are studied. These results indicate the possibility of adjusting the band gap by appropriately choosing the concentration of dopants and their location in the graphene crystal lattice.

The recent taxonomic diversification of bacterial genera Pectobacterium and Dickeya, which cause soft rot in plants, focuses attention on the need for improvement of existing methods for the detection and differentiation of these phytopathogens. This research presents a whole genome-based approach to the selection of marker sequences unique to particular species of Pectobacterium. The quantitative real-time PCR assay developed is selective in the context of all tested Pectobacterium atrosepticum strains and is able to detect fewer than 102 copies of target DNA per reaction. The presence of plant DNA extract did not affect the sensitivity of the assay.

Aim. Comparative analysis of the efficiency of metal-complex (πQ1983, πQ2721) and aminothiol (Amtizole, Sunazole) antihypoxants in experiments on rats exposed to acute hypoxia with hypercapnia. Methods. Experiments performed on 182 male rats of Wistar line weighing 150-170 g. The study of antihypoxic activity of substances was carried out on the model the AH+Hc. The condition of acute hypoxia in rats was formed by placing them in glass airtight containers with a free volume of 1.0 L. Antihypoxic effect was evaluated by the life expectancy of animals in the described conditions. Substances πQ2721, πQ1983, Amtizole and Sunazole was administered once intraperitoneally at doses of 25, 50 and 100 mg/kg. Previously each substance was dissolved in 0.9% NaCl (1.0 ml). Testing the effectiveness of the substances on AH+Hc model was carried out after 1 h after administration of the substances and after 24 h. Animals of control groups were injected with 1.0 ml of 0.9% NaCl. In animals exposed to test AH+Hc in 1 h after administration were performed measurements of the rectal temperature before the experiment and through 1 h after administration, i.e. before AH+Hc. In animals selected for 24-hour observation, rectal temperature was measured before the experiment, and then after 1, 3, 6, 12, 18 and 24 h of observation, after which they were exposed to AH+Hc. Results. The antihypoxic effect of a selenium-containing substance πQ2721 based on Zn2+ was confirmed in experiments on rats. In a number of substances for comparison the πQ2721 proved himself not only as equally effective. It is found that after 1 h after administration at a dose of 50 mg/kg πQ2721 superior to all studied compounds, including antihypoxant with succinate Sunazole. An important advantage of the new promising antihypoxic agent was the preservation of its action for 24 hours after injection. (For citation: Evseev AV, Surmenev DV, Evseeva MA, et al. Comparative analysis of metal-complex and aminothiol antihypoxants efficiencies in the experiment. Reviews on Clinical Pharmacology and Drug Therapy. 2018;16(2):18-24. doi: 10.17816/RCF16218-24).

Aim. To test the new selenium containing metal complex (Zn2+) compounds by acute hypoxia-hypercapnia method in experiments on mice for antihypoxic effect finding. Methods. The screening of antihypoxants in experiments on mice placed in acute hypoxia-hypercapnia condition (AH + H) among 11 new metal complex selenium containing compounds have been performed. Condition of AH + H in animals was formed by their placing in hermetic glass boxes with 0.25 L free volume. Each substance has been used once by intraperitoneal introduction 60 min. before mice placing in AH + H area in doses 10, 25, and 50 mg/kg. The “life span” parameter was used as a criterion of antihypoxic activity. At the definite steps of investigation all animals where undergone to rectal temperature measuring. Results. The antihypoxic effect was shown by 4 compounds among 11 (πQ2719, πQ2720, πQ2721, πQ2882). The greatest result in life span was found in substance πQ2721. In this case the right positive interaction between doses of substances and results was marked - doses 10, 25 and 50 mg/kg provide life span enlargements to 25.1, 81.7 (р < 0.05), and 186.1% (р < 0.005) in comparison with control groups correspondently. The efficiency of etalon substance πQ1983 was near to that of πQ2721 but in dose 50 mg/kg it becomes weaker in activity than new compound. Conclusion. The test resultant of 11 new metal complex (Zn2+) substance with selenium in structure of ligand in use of acute hypoxia-hypercapnia method shows the πQ2721 as an antihypoxant that was confirmed by significant mice life span enlargement after doses 25 and 50 mg/kg during its action that according with dose-dependent rectal temperature decrease. (For citation: Yevseyev AV, Surmenev DV, Parfenov EA, et al. Testing of new selenium containing metal complex compounds by acute hypoxia-hypercapnia method. Reviews on Clinical Pharmacology and Drug Therapy. 2017;15(4):46-52. doi: 10.17816/RCF15446-52).

Anthropogenic air pollution attracts attention of scientists and the public around the world for many years. Traveling over vast distances, particles and aerosols pollute the environment many kilometers away from emission sources. Primary anthropogenic aerosols enter the air mainly with industrial emissions from factories. Secondly aerosols are formed in the atmosphere through various physical and chemical processes involving water vapor, organic compounds, etc. This group includes sulphur dioxide. The article discusses issues related to the pollution of the environment as a result of the activities of the copper-nickel plant Severonickel, located on the Kola Peninsula. In particular, the problem of accumulation of sulfur compounds in the soil, which occurs over decades at a different distance from the industrial factory. Sulphur dioxide is a toxic substance, at high concentrations in the air there is a harmful impact on living organisms, precipitation leads to acidification of the soil, disturbance of soil and vegetation cover, changes balance and destroy ecosystems. For this reason, it is important to monitor the condition of ecosystems that are under the influence of industrial plants. This issue is dedicated to the work of researchers and students of the Department of Environmental Management of the Faculty of Geography of Lomonosov Moscow State University, who for more than twenty years have been monitoring the state of ecosystems in the impact zone of Severonickel plant, including a number of studies devoted to pollution of the soil with sulfur compounds.

We have studied structural and electronic properties of fluorinated graphene with different coverage of fluorine using first-principles calculations based on the density functional theory. The atomic structures and electronic structures of fluorinated graphene are investigated. Our results show that the electronic properties of a fluorinated graphene sheet exhibit strong dependence on the degree of fluorination. Our study suggests that the property of graphene can be modified by absorbing different amounts of fluorine.

The article discusses the effects of cetyltrimethylammonium bromide, sorbed on activated carbons, on vital signs of some living systems.Extracts from carbon, saturated with cetyltrimethylammonium bromide, were injected into the organisms of laboratory mice and soil samples. The biochemical blood parameters were determined from laboratory mice. In soils was determined the enzymatic activity, as well as the number of major groups of soil microorganisms.In mice, under the influence of surfactants on active carbons, the activity of enzymes associated with the functioning of the liver changes to a greater extent. The effect on the urease activity of the soil was not detected, the phosphatase activity under the action of surfactants increases, catalase and dehydrogenase - fall. The number of oligonitrophils, oligotrophs and amylolytics is reduced. A decrease in the effect of surfactant bonded to the active carbons surface on the systems as compared with free surfactants has been recorded.The increase in the number of ammonifiers with the introduction of surfactants can be used for microbiological cleaning of waste active carbone.

The developed absorbing microwave energy coatings of TiO2 and Al2O3/TiO2 deposited by the detonation method were investigated in this work. Thermal cyclic tests of the obtained samples of different layer thickness on copper substrates were carried out, the phase composition of the obtained coatings was investigated, the effect of high-temperature heating in hydrogen on the phase composition of the coating and its stability was determined. The gas emission was studied on evacuated and degassed experimental model.

Highly precise calculations of analytical Hartree–Fock orbitals and energies have been performed within the limits of the Roothaan–Hartree–Fock atomic theory (Roothaan–Bagus method) for all open p-shell atoms of the Periodic Table. They were calculated in an algebraic approach using Slater-type atomic orbitals (AOs) as basis functions. Nonlinear parameters (orbital exponents) of AOs were optimized with exceptional accuracy by second-order methods. As a result, it was possible to satisfy exactly the virial relation (10–14–10–17) with calculated atomic term energies being close to the Hartree–Fock limit.

Application of the Roothaan-Bagus method (Hartree-Fock atomic theory) for atoms with one open fn-shell is considered. Energy values for lanthanide atoms in the ground and excited states are calculated by minimization methods of the first and second orders within the limits of Roothaan-Hartree-Fock atomic theory using orbital exponents of Slater-type atomic orbitals.

The paper reports on the test data on the elastic-plastic deformation of mottled sylvinite and rock salt under trialxial compression conditions. The basic regularities are established for variations of strain and strength parameters of salt rocks depending upon the structure and shape of specimens and the loading rates.

We studied the effects of complex N-acetyl-L-cysteine compounds with transitional biometals on the inflammatory and adaptation reactions. Some compounds were superior to known antihypoxants and actoprotectors and exhibited significant antiinflammatory activity.

Countercurrent chromatography (CCC) works with a liquid stationary phase. It is proposed to create a concentration gradient in the stationary phase during the chromatographic run. The gradient concentration is initiated putting a known volume of neat stationary phase at the head of the CCC column and a known volume of dithizone (a test die) concentrated stationary phase at the end of the CCC column. Water‐organic solvent biphasic liquid systems were tested. The aqueous phase is the mobile phase. Hexane, decane, chloroform, methylisobutyl ketone, tetrachloromethane, or ethyl acetate were used as the dithizone containing stationary phase. It was found that the concentration gradient created inside the column is dependent on the operational hydrodynamic parameters and physicochemical properties of two‐phase liquid systems used. The water‐organic solvent liquid systems were divided into two types: 1. “Nimble” (easily mixed) systems that readily form concentration gradients, which can be completely le...

Aspects of applying n-pulse periodic initiation in pulsed laser polymerization/size-exclusion chromatography (PLP/SEC) experiments are studied via simulation of molecular weight distributions (MWDs). In n-pulse periodic PLP/SEC, sequences of n laser pulses at successive time intervals Δt 1 up to Δt n are periodically applied. With the dark time intervals being suitably chosen, n-modal MWDs with n well separated peaks occur. The n-pulse periodic PLP/SEC method has the potential for providing accurate propagation rate coefficients, k p . Among several measures for k p , the differences in molecular weights at the MWD peak positions vield the best estimate of k p under conditions of medium and high pulse laser-induced free-radical concentration. Deducing k p from n dark time intervals (corresponding to n regions of free-radical chain length) within one experiment at otherwise identical PLP/SEC conditions allows addressing in more detail a potential chain-length dependence of k p . Simulations are compared with experimental data for 2-pulse periodic polymerization of methyl methacrylate.

A numerical procedure is developed which allows taking into account the chain length dependence of the termination and propagation constants for calculating molecular weight distributions (MWDs) formed under free-radical polymerization initiated by an arbitrary sequence of laser pulses. The law k p L = k p 0 L -β1 + (k p 1 - k p 0 )L -β2 (where k p 0 is a constant close to the experimentally determined propagation rate constant, k p 1 is the constant of the propagation of radicals with unity degree of polymerization, β 1 and β 2 are constants reflecting the chain length dependences of the propagation of long-chain and ultra-short radicals, respectively) is considered for description of the chain length dependence of the propagation constant. The effect of this dependence on MWDs is considered in detail. It is shown that the time dependence of the chain length of growing radicals, ψ(t), can be used for model-independent determination of chain-length-dependent propagation constants k p L . Theoretically the well-known pulsed laser polymerization (PLP) method for evaluation of the propagation constant can be used for determination of ψ(t), but this determination is questionable in practice. Direct application of this method gives L/∫ 0 L dL'/RL'P instead of k p L . The consideration of methyl methacrylate polymerization at 25°C as an example shows that the weak chain length dependence of the long-chain k p value with β 1 0.01 (if the propagation constant is assumed to be equal to a constant value) and k t L,L /k p L values of these radicals with uncertainty

For polymerization initiated by an arbitrary sequence of laser pulses a numerical technique for calculating molecular weight distributions (MWDs) is developed, which takes into consideration the chain length dependence of the termination rate constant k t . The MWDs for methyl methacrylate and styrene are calculated by use of a and k 0 values (for the law k ij t = k 0 (i) -a of termination of radicals with chain length i) and averages (i, j) (for rate constants k ij t = k 0 (i, j) of termination of radicals with different degrees of polymerization) taken from the literature. The dependences of the overall termination constant (k t ) on initiation parameters (pulse repetition rate (v) and pulse intensity for initiation by periodic laser pulses) are presented. Two methods are proposed for a and k 0 determination : a) by experiments on polymerization with periodic laser pulses where monomer-to-polymer conversions per pulse are determined for different v; b) by experiments on polymerization with packets of pulses where the constants k p (the rate constant of propagation), a and k 0 can be determined simultaneously from MWD. For both methods simple analytical equations are derived for evaluation of the constants. The limits of application of the methods are determined by use of the numerical technique for MWD calculation.

Molecular weight distributions (MWDs) under free radical polymerization initiation by an arbitrary sequence of radiation pulses have been investigated. Analytical expressions enabling to account for influence of the polymer chains linear termination (for example, inhibition) have been obtained. On the basis of these expressions the MWDs generated by pulse-periodic radiation have been investigated theoretically. The calculated MWDs for polymerization in the presence of high concentration of retarder have been given and the influence of the inhibitor burning within the irradiation process on the MWDs character have been studied. It has been shown that possibility to employ the PLP method for determination of polymerization rate constant (kp) depends significantly on the efficiency ofchains linear termination: the PLP method can be confidently used at τ > T (where τ is the effective lifetime of growing radicals, T is the pulse irradiation period) and it is doubtful if τ < T/3. The expression for specifying of pulses number required for establishment of pseudostationary polymerization has been obtained for the polymerization at high concentration of retarder. The calculated MWDs for polymerization of MMA are presented.

An investigation of molecular weight distributions (MWDs) resulting from initiation of free radical polymerization by an arbitrary sequence of short laser pulses has been undertaken. The analytical expressions have been derived to calculate MWDs for a polymerization scheme that contains reactions of chain initiation, propagation and termination by recombination or disproportionation. The MWDs produced by pulse-periodic irradiation have been calculated for a wide range of initiating pulses repetition rates (f = 0.05–100 Hz). The MWD dynamics in the act of polymerization and the influence of the duration of polymerization pseudostationary regime establishment upon the MWD have also been studied. The suitability of the derived expressions for describing the MWD generated by CW radiation before and after the establishment of polymerization quasi-stationary regime has been considered.

Polymerisation of OKM-2 and TGM-3 films was photoinitiated by pulse-periodic XeCl laser radiation (λ = 308 nm). The radiation-dose dependences of the mass and thickness of hardened films, and of the degree of conversion of double bonds were determined for polymerisation both in air and in an inert gas. A study was made of the influence of the energy density of laser pulses on the polymer yield. The changes in the transmission spectra of the irradiated films were studied. The energy expenditure in the hardening of the films depended strongly on the energy density of the laser pulses. The parameters of the polymerisation kinetics were estimated.

1. The cyclic instability associated with the alloys tested is a function of their structural instability at the test temperature. 2. The increase in the cycle threshold amplitude for structurally unstable alloys at high temperatures is due to the increased friction stress that prevents movement by the dislocations. The increased friction stress is related to the pinning of the dislocations by precipitates.

The fabrication of three-dimensional (3-D) structures using computer-controlled ultraviolet (UV) photopolymerization of acrylates (laser stereolithography) often results in the trapping of residual unreacted monomer and initiator. These residuals can leach from the finished structure and affect the biological response of cells and tissues. Thus the potential applications of these structures for tissue engineering have not been fully realized. In this paper we demonstrate that conventional post-lithography treatments followed by processing in the environmentally benign solvent, supercritical carbon dioxide (scCO(2)), dramatically increased biocompatibility. The scCO(2) processing of pure polyacrylate and polyacrylate/hydroxyapatite composite structures extracts residuals from all structures including those that had received full conventional post-lithography treatment (acetone washing/UV drying). Human osteoblast cells seeded on the extracted surfaces of these structures demonstrated increased cell attachment and proliferation on the scCO(2)-treated materials.

In present paper we describe the development of advanced laser stereolithography (LS) methodology based on photopolymerisation of a new liquid mixture of polyfunctional acrylic monomers and osteoinductive hydroxyapatite powder. Supercritical carbon dioxide treatment of LS samples introduced both surface and bulk microporosity for enhanced primary cell attachment and to remove toxic additives improving biocompatibility of the materials. The results of in vitro tests comprising human osteoblast cells attachment, spreading and proliferation on the implants demonstrate low level of their cytotoxicity and high level of biocompatibility. We also present a novel Surface Selective Laser Sintering (SSLS) technique for biodegradable polymer scaffolds fabrication from thermosensitive poly(D,L-lactic) - and poly(D,L-lactic-co-glycolic) acids - polymers, which have a wide spread occurrence in biomedical applications. Unlike conventional Selective Laser Sintering (where the powder particles melt because of their volumetric absorption of the laser radiation), in SSLS initiation of the sintering occur due to near IR laser beam absorption by a small amount (

A new approach to the spectroscopy of highly excited vibrational states of polyatomic molecules has been elaborated. The molecules of CrO 2 Cl 2 were prepared in states with a vibrational energy of the ground electronic term A 1 of ≈ 19000 cm −1 by means of internal conversion of electronic energy from the electronic state B 1 excited by laser radiation. The spectroscopy of the vibrationally excited molecules has been carried out in the region of the ν 6 and ν 1 bands with diode and CO 2 lasers. The fwhm of the obtained spectrum was ≈ 15 cm −1 . The intermode interaction in CrO 2 Cl 2 has been theoretically analyzed, and the calculated spectrum compared with that measured experimentally. The time evolution of the spectrum of vibrationally excited CrO 2 Cl 2 molecules has been studied. The average energy transferred per one collision with unexcited CrO 2 Cl 2 molecules was equal to 〈δ E 〉 ≈ 1200 cm −1 .

The three-frequency IR excitation of visible luminescence was used as the method for probing of the IR multiphoton absorption of OsO4 molecules cooled in a supersonic jet. The first laser pulse was used to form a certain vibrational distribution below the onset of vibrational quasicontinuum. The possibility of direct excitation of the vibrational states ν = 2, 3 of pumped ν3 mode by direct two- or three-photon absorption has been shown. The excitation spectra under the influence of the second variable laser frequency show the features attained for transitions from initially prepared vibrational levels ν = 2 or ν = 3. The dependencies of the luminescence intensity on the IR laser fluence were studied also to prove the role of the direct multiphoton transitions. The different multiphoton and multifrequency resonances were analysed in the frame of simple spectroscopic model, and appropriate anharmonicity constants were derived.

A simple method to obtain from a single CO2 laser a multiple-frequency radiation suitable for experiments in laser chemistry is suggested and experimentally realized.