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Abstract Objective The resurgence of lumpy skin disease virus isolates of different genotypic natures abolishes the accuracy of assays that target either vaccine or field strain genome. The aim of the present study was to develop a universal real-time PCR assay using TaqMan chemistry to cover field, vaccine, and recombinant strains of lumpy skin disease virus isolates. Results The PCR assay was designed based on a LSDV044 target region that offers a unique identification locus to facilitate the sensitive and specific detection of all isolates known to date. The efficiency of amplification, determined over five orders of magnitude, was 93%, with the standard deviation remaining in the range of 0.11–0.23. Evaluation of the assay repeatability on three different days revealed that the inter-run variability ranged from 0.83 to 1.22 over five repetitions across three runs. This new screening assay is proposed as a fast, efficient, and sensitive tool that can be employed in the basic or applied surveillance studies regardless of the genotype. Moreover, the assay can be used for the routine laboratory testing of animal samples during eradication programs for lumpy skin disease.

The use of unmanned aerial vehicles (hereinafter referred to as “UAV”) is one of the most popular ways of collecting objective spatial data on the land plots under survey. The main advantages of UAVs include the significantly lower cost of surveying, design and complex cadastral works compared to traditional methods of determining coordinates (e.g. performing a tacheometric survey and plane-table survey). The designed sector of block No. 9 in the Yurga urban district of Kemerovo region with cadastral No. 42:36:0102001 (land category: residential), comprising 22 apartment buildings, is taken as an example. The economic performance of land plots marking, carried out with cadastral accuracy, based on data obtained using UAVs and without the use thereof, is assessed.

The structural features and thermophysical and transport properties of dense nonporous membranes of the casting type from (co)polyamide-imides synthesized by the polycondensation of the diacid chloride of 2-(4-carboxyphenyl)-1,3-dioxoisoindoline-5-carboxylic acid and diamines 5,5'-methylene-bis (2-aminophenol) (DADHyDPhM) and 4,4'-methylenebis(benzeneamine) (DADPhM), taken in molar ratios of 7:3, 1:1, and 3:7, have been studied. The effect of hydroxyl-containing modifying fragments of dihydroxy diphenylmethane introduced in various amounts into the main polymer chain on the pervaporation properties of the formed films is discussed. It has been shown that the presence of the residual solvent N-methyl-2-pyrrolidone in the films not only has a plasticizing effect on the characteristics of film membranes but also promotes the preferential transmembrane transport of polar liquids, primarily methanol (permeation rate over 2 kg for a copolymer with a ratio of DADHyDPhM:DADPhM = 7:3). The removal of the residual solvent from the polymer film, both thermally (heating to 200 °C) and by displacement with another solvent as a result of sequential pervaporation, led to a significant decrease in the rate of transfer of polar liquids and a decrease in the selectivity of the membrane. However, the dehydrocyclization reaction resulted in more brittle films with low permeability to penetrants of different polarities. The results of our comprehensive study made it possible to assume the decisive influence of structural changes in membranes occurring in connection with the competitive formation of intra- and intermolecular hydrogen bonds.

The structure, thermophysical characteristics, and pervaporation properties of composite membranes based on poly(vinyl alcohol) (PVA) are studied in dependence of the film preparation conditions. It is shown that the nature of the supramolecular organization of the composite polymer film determines which of the components of the separated mixtures of toluene and heptane predominantly penetrate through the corresponding pervaporation membrane. The observed structural effects can become more pronounced if the second component of a polymer mixture is purposefully selected (in this case, poly(N,N-dimethylaminoethyl methacrylate) instead of poly(acrylic acid)) or a nano-sized filler that can be well dispersed in the polymer matrix is introduced. Multi-wall carbon nanotubes are introduced into binary PVA-containing polymer blends. The influence of these fillers on the structure and transport properties of the obtained membranes is studied.

The structure and transport properties of the new Cellokon-AKH membrane based on animal cellulose obtained from tunic of ascidian Halocynthia aurantium were studied. The results of scanning electron microscopy (SEM), FTIR spectroscopy, and the X-ray diffraction data revealed significant differences in the structure and morphology of upper and lower surfaces of this layered film membrane based on animal cellulose. It was shown that the membrane surface is a network of intertwined cellulose fibers, with both denser and looser areas present on the lower surface compared to the completely uniform morphology of the main part of the upper surface. The hierarchical structure of tunicin-based outgrowths evenly distributed over the upper surface was determined and analyzed. The 3D visual representation of the surface structure was performed with the surface reconstruction technique using scanning electron microscope images. A surface model was calculated from the aligned images based on the photogrammetric approach. The transport properties of samples with different prehistory with respect to ethanol, water, and their mixtures of different compositions were studied depending on the pressure. Representing an alcohol-containing gel film in its original state, as solvents are removed, the membrane transforms into a low-permeability fibrillary organized selective film. The obtained results confirmed the possibility of using Cellokon-AKH (dried form) for the filtration of substances with a molecular weight of more than 600 Da in various media. Further study of this new material will allow to get closer to understanding the structure of the studied seabed inhabitants and to use these natural resources more efficiently.

Polymer film membranes are used to solve specific separation problems that dictate structural requirements. Structural and morphological parameters of film membranes based on glassy polyheteroarylenes can be controlled in the process of preparation from solutions that opens up prospects for obtaining structured membranes required for targeted separation. In the case of aromatic poly(amide-imide)s, the possibility of controlling film formation and structure virtually has not been studied. In the present work, a series of homologous co-poly(amide-imide)s differing in the number of repeating units with carboxyl-substituted aromatic fragments was synthesized by polycondensation. Comparative analysis of the processes of formation of membranes with different morphologies based on these polymers under equal conditions was performed. New information was obtained about the influence of the amounts of carboxyl groups and the residual solvent on structural properties of asymmetric membranes. The influence of these factors on transport properties of dense membranes under pervaporation conditions was studied. It was demonstrated that in the case of carboxyl-containing poly(amide-imide)s, the domains formed during film preparation had a significant effect on membrane properties.

This study investigates the thermal and structural properties of multilayer composites based on chitosan (CS) and polyanions with different functionalities, including sodium sulfoethyl cellulose (SEC), sodium alginate (ALG), and sodium hyaluronate (HA). Unlike polyelectrolyte complexes (PECs) obtained by polymer mixing, the formation of a PEC layer by a process of layer-by-layer deposition of oppositely charged polymers is accompanied by the transformation of the CS polymorphic state, and this affects the relaxation and thermal properties of the resulting multilayer composite. X-ray diffraction analysis showed that the formation of the PEC layer in the CS/SEC multilayer film is accompanied by crystallization of the CS chains and the formation of a predominantly anhydrous CS modification. Thermogravimetric analysis of the CS/SEC film registers a high-temperature peak associated with the thermal decomposition of crystalline CS in the PEC composition. According to the dynamic mechanical analysis, the CS/SEC composite was characterized by a single glass transition temperature, indicating a strong interaction between the layers when using SEC (a strong acid salt) as the counterion to CS. For multilayer composites with weak polyacid salts (ALG and HA), the crystallization of CS in the PEC layer is weaker, as reflected in the thermal degradation of these films. A high-temperature peak is recorded in the thermal decomposition of CS/HA and is absent in the case of CS/ALG. Dynamic mechanical analysis of the CS/ALG composite showed two glass transition temperatures close to those of the original polymers, indicating weak PEC formation. The CS/HA composite showed an intermediate response. Thus, the effect of the PEC layer on the properties of the poly-layer composites decreases in the order CS/SEC > CS/HA > CS/ALG.

This review summarizes the features of cold shock domain (CSD) proteins in the context of their interactions with nucleic acids and describes similarities and differences in the structure of cold shock proteins of prokaryotes and CSD proteins of eukaryotes with special emphasis on the functions related to the RNA/DNA-binding ability of these proteins. The mechanisms and specificity of their interaction with nucleic acids in relation to the growing complexity of protein domain structure are described, as well as various complexes of the mammalian Y-box binding protein 1 (YB-1) with nucleic acids (filaments, globules, toroids). The role of particular amino acid residues in the binding of nitrogenous bases and the sugar-phosphate backbone of nucleic acids is emphasized. The data on the nucleic acid sequences recognized by the Y-box binding proteins are systematized. Post-translational modifications of YB-1, especially its phosphorylation, affect the recognition of specific sequences in the promoter regions of various groups of genes by YB-1 protein. The data on the interaction of Lin28 protein with let-7 miRNAs are summarized. The features of the domain structure of plant CSD proteins and their effect on the interaction with nucleic acids are discussed.

Self-supporting multilayer films containing a polyelectrolyte complex (PEC) were prepared by the sequential layering of sodium hyaluronate (HA, MW 5.4 × 10 4 ) and chitosan (CS, MW 1.6 × 10 5 , the degree of deacetylation 0.80) in different orders. Imaging with low-voltage scanning electron microscopy (LVSEM) showed that the CS/HA films had a multilayer structure, while X-ray diffraction (XRD) indicated significant structuring of the CS layer near the PEC-CS region. Analysis of the thermal properties of the CS/HA films revealed differences in the structural organization and morphological features of the polymer layers and high thermal stability of the PEC layer. Testing of the transport properties of the CS/HA film in pervaporation (PV) separation using different compositions of ethanol-water mixtures indicated that the multilayer membrane was selective across a wide range of concentrations in the feed. Separation of an azeotropic ethanol-water mixture containing 5 wt% water yielded a permeate consisting of about 100 wt% water. LVSEM revealed that the membrane microstructure changed during the PV process due to membrane swelling and changes in the arrangement of the macromolecules during transport of the penetrant. The results support the use of CS/HA composite films as highly effective PV membranes. In addition to pervaporation separation, CS/HA multilayer films can also be used for drug delivery, tissue engineering, and wound healing applications., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

A polyelectrolyte complex (PEC) was prepared from chitosan (CS) and λ-carrageenan (λ-CAR) using a layer-by-layer deposition of polyion solutions on a plated nonporous support. This material was then used as a multilayer membrane for the pervaporation separation of aqueous ethanol solutions. The fabricated complex film (25-30μm thick) was a multilayer system (λ-CAR-PEC-CS) containing a polycation CS (MW 3.1×10 5 , DDА 0.93), a polyanion λ-CAR (MW 3.5×10 5 , extracted from the alga Chondrus armatus), and a PEC layer formed between the two polyion layers. X-ray diffraction indicated a significant structuring of the film in the region of the composite PEC-CS bilayer. The structural and morphological characteristics of the CS surface in the multilayer membrane, as revealed by atomic force microscopy, were close to the characteristics of the dense CS film. However, this structure changed following pervaporation (i.e., the distinct spherical structures on the surface disappeared). Similarly, the initially loose surface of λ-CAR in the composite changed to an ordered domain after pervaporation. The transport properties of the pervaporation membranes were tested by examining the separation of ethanol-water mixtures of different compositions. The flux increased with an increase in the weight percentage of water in the feed mixture, but the separation capacity of the membrane was unchanged. In a range of feed concentrations of 50-94wt%, the membrane mainly releases water with a corresponding concentration in the permeate of 99.9-99.8wt% and substantial fluxes of 0.003-1.130kgm -2 h -1 at 40°C. The obtained results indicate significant prospects for the use of non-gelling type CARs for the formation of highly effective pervaporation membranes., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Two-ply composite membranes with separation layers from chitosan and sulfoethylcellulose were developed on a microporous support based on poly(diphenylsulfone- N -phenylphthalimide) and investigated by use of X-ray diffraction and scanning electron microscopy methods. The pervaporation properties of the membranes were studied for the separation of aqueous alcohol (ethanol, propan-2-ol) mixtures of different compositions. When the mixtures to be separated consist of less than 15 wt % water in propan-2-ol, the membranes composed of polyelectrolytes with the same molar fraction of ionogenic groups (-NH₃⁺ for chitosan and -SO₃ - for sulfoethylcellulose) show high permselectivity (the water content in the permeate was 100%). Factors affecting the structure of a non-porous layer of the polyelectrolyte complex formed on the substrate surface and the contribution of that complex to changes in the transport properties of membranes are discussed. The results indicate significant prospects for the use of chitosan and sulfoethylcellulose for the formation of highly selective pervaporation membranes.

This corrects the article DOI: 10.1134/S0006297917090012.

Formation of appropriate gut microbiota is essential for human health. The first two years of life is the critical period for this process. Selection of mutualistic microorganisms of the intestinal microbiota is controlled by the FUT2 and FUT3 genes that encode fucosyltransferases, enzymes responsible for the synthesis of fucosylated glycan structures of mucins and milk oligosaccharides. In this review, the mechanisms of the selection and maintenance of intestinal microorganisms that involve fucosylated oligosaccharides of breast milk and mucins of the newborn's intestine are described. Possible reasons for the use of fucose, and not sialic acid, as the major biological signal for the selection are also discussed.

Aim: To analyze actual drug consumption based on the defined daily dose (DDD analysis) and to analyze the utilization of drugs based on their proportion of the total defined daily doses (DU90% analysis) for the antimicrobial therapy of community-acquired pneumonia (CAP) in clinical practice at a hospital in Russia., Material and Methods: The investigation materials were the data of 117 case histories of male (51.3%) and female (48.7%) patients hospitalized with CAP at Nizhny Novgorod City Clinical Hospital Five in 2015. The investigation enrolled all the patients admitted to the hospital over the analyzed period. DDD analysis and DU90% analysis were used as study methods., Results: DDD analysis and DU90% analysis of antimicrobial therapy for CAP were carried out at the hospital in clinical practice during a year. The annual number of defined daily doses (NDDD) for antimicrobial drugs, the number of defined daily doses per 100 bed-days (NDDD/100 bed-days), and a drug load (g) per 1000 CAP patients per day and per CAP patient per year were determined. The largest NDDD/year for CAP treatment with ceftriaxone was 376 g, or 43.43 NDDD/100 bed-days, which is much higher than that with other antimicrobial agents. The daily drug load of ceftriaxone per 1,000 CAP patients was 8.8 g, which exceeds that of moxifloxacin by 18.7 times, azithromycin and levofloxacin by 5 times, and ampicillin/sulbactam by 2.3 times. The daily drug load of ceftriaxone per CAP patient was 3.2 g, which exceeds that of of ampicillin/sulbactam by 2.3 times, levofloxacin and azithromycin by 5 times, and moxifloxacin by 19 times., Conclusion: It may be recommended that the proportion of cephalosporins as drugs that promote the rise of resistance in microbes and their production of extended-spectrum β-lactamases should be further limited, the proportion of penicillins be extended, and the administered ampicillin/sulbactam be added, for example, by amoxicillin/clavulanate. Penicillins contribute to the rise of resistance to a lesser degree, and the use of two different penicillin molecules specified in the guidelines for the treatment of CAP will be able to slow the process further. By the same reasoning, it is also advisable to use cefuroxime (second-generation cephalosporins) along with ceftriaxone in patients in stable condition, without impairing vital functions.

Aim: By using the risk concept, to determine a quantitative relationship between smoking in patients with chronic obstructive pulmonary disease (COPD) and the development of an exacerbation., Subjects and Methods: Case history data were studied in 166 patients admitted for a COPD exacerbation in 2009 to 2012. There were 2 exacerbations for a year or longer. The patients were divided into 2 groups: smokers (n=110) and nonsmokers (n=56). The concept for estimating the risks was based on the calculation of absolute risk in the exposed and unexposed groups, attributable risk, relative risk, and population attributable risk and on the determination of standard errors for each type of risk and confidence interval., Results: The methodological aspects of determining the quantitative relationship between smoking in patients with COPD and the development of its exacerbations (twice or more per year) were considered on the basis of the statistical concept of risk factors. A risk factor concept-based analysis has shown that the impact of smoking is directly related to the worsening of COPD. The frequency of exacerbations is 71.8% in the group of smoking patients and 32.1 % in that of nonsmoking patients; the risk factor increases the likelihood of this event by 39.7%., Conclusion: Smoking leads to a 2.2-fold increase in the frequency of COPD exacerbations. The potential hazard index was 2.5.

The paper considers the state-of-the-art of membrane technologies, as applied to the needs of medicine and ecology, the major benefits of membranes for microfiltration and ultrafiltration, and perspectives for the application of new membranes based on new materials. A number of membranes based on aromatic polyamide imides (PAs) have been investigated using rotavirus models. Due to the good solubility of PAs in amide solvents, their based asymmetric membranes can be formed in one step, by applying a water setting bath. The one-stage procedure developed at the Institute of High Molecular Compounds, Russian Academy of Sciences, for the synthesis of aromatic PAs allows one to prepare polymers with required viscosity and strength characteristics. This gives rise to a membrane as porous films of digitiform morphology and asymmetric porous structure.

A system has been developed for in vitro testing of E. coli C-P-lyase (the enzyme cleaving C-P bonds in phosphonates). NADH, ATP, and the system of ATP regeneration were necessary but not sufficient for expression of the C-P-lyase activity in cell-free extracts of E. coli. Experimental evidence suggests that glucose 6-phosphate and (or) glucose activate C-P-lyase, serving as precursors in the formation of (alkylphosphono)ribose, an intermediate in the reaction. Guanine is the most likely acceptor of the phosphate group.

Phosphonates are a class of organophosphorus compounds characterized by a chemically stable carbon-to-phosphorus (C-P) bond. Wide occurrence of phosphonates among xenobiotics polluting the environment has aroused interest in pathways and mechanisms of their biodegradation. Only procaryotic microorganisms and the lower eucaryotes are capable of phosphonate biodegradation via several pathways. Destruction of the non-activated C-P bond by the C-P lyase pathway is of fundamental importance, and understanding of the process is a basic problem of biochemistry and physiology of microorganisms. This review offers analysis of available data on phosphonate-degrading microorganisms, degradation pathways, and genetic and physiological regulation of this process.

The efficiency of secretion of Escherichia coli alkaline phosphatase depends on the presence in cells of a cytoplasmic chaperone--protein SecB. Secretion increases in the presence of this chaperone at 30 degrees C, which is the most favorable for the interaction of SecB with the export-initiation domain found previously in the N-terminal region of the mature enzyme. This interaction most likely occurs in the region of the export domain, which is located close to the signal peptide and in complex with a translocational ATPase--protein SecA.

The export signal has been assumed to be localized not only in the signal peptide of a secreted protein precursor, but also in the N-terminal region of the mature polypeptide chain. Mutant alkaline phosphatases with amino acid substitutions of two positively charged residues (Lys or Arg) in this region at different distances from the signal peptide have been studied to test this assumption. The efficiency of secretion has been shown to decrease in mutant proteins with amino acid substitutions in the region of 16-18 amino acid residues; the closer to the signal peptide is the substitution, the greater is the decrease. A change in the primary structure of the N-terminal domain results also in an increase in the Michaelis constant, which is greater the farther is the amino acid substitution from the signal peptide, suggesting a change in the enzyme function as well.

Thirteen investigated strains of ascomycetous yeasts able to produce secretory heat-shock proteins (sHSPs) do not response equally to a high temperature by induction of the synthesis and secretion of these proteins. In this respect the above yeasts can be divided into three groups having a positive (I), a negative (II), and an indefinite reaction (III) to the heat shock. The thermotolerant yeast Hansenula polymorpha belongs to the first group. In this yeast heat shock induces the synthesis and secretion of sHSP gp280. This new representative differs from known sHSPs in molecular mass and subunit composition. In other respects (glycosylation, mainly extracellular localization, and the character of export into the culture medium) it displays similar properties.

Using affinity-purified rabbit polyclonal antibodies against an extracellular mannoprotein (gp400) of Saccharomyces cerevisiae, the presence of immunohomologic proteins with similar electrophoretic mobility was shown in the culture medium of S. bayanus, S. paradoxus and S. pastorianus. Cross-reactive bands with different electrophoretic behaviour were observed for S. dairensis, S. exiguus, S. kluyveri, S. unisporus and also for the species moved from Saccharomyces to Arxiozyma, Kluyveromyces, Pachytichospora, Torulaspora and Zygosaccharomyces, in contrast to ascosporous yeasts of other genera in which these proteins were not found.

A new secreted yeast glycoprotein with an Mr of about 400 kDa (gp400) has been found. The glycoprotein is an O-mannosylated oligomer, whose synthesis and export into culture medium are stimulated by heat shock. Intracellular transport of gp400 is carried out by membrane vesicles distinct from the known constitutive secretory vesicles. Immunological analysis revealed gp400 only in Saccharomyces species.

Human ceruloplasmin (Cp) molecule is split into fragments by a contaminating protease upon storage of enzyme preparations. These fragments were separated by SDSPAAG electrophoresis and their Mr were estimated. Separate fragments were subjected to immunoelectrophoresis in agarose gel containing rabbit antibodies to human Cp. The immunoprecipitation peaks were then specifically stained to reveal the oxidase activity of the fragments towards o-dianisidine and L-cysteine. All the fragments were able to oxidize the latter, however, only the whole Cp molecule and the two of its largest fragments could oxidize the former. It seems likely that oxidation of L-cysteine does not require the presence of several copper ions constituting the catalytic centre of the blue oxidase (Cp.). contrarily, o-dianisidine seems to be oxidized by the multicopper active site of the enzyme rather than by the autonomously acting singular copper(s). Since o-dianisidine is oxidized by the fragments of Cp lacking the C-terminal polypeptide, which was thought to bind all the coppers of the active centre, it was assumed that some of the latter are bound by amino acids located in another part of the molecule.