263 research outputs found

    The role of non-commercial cyprinids in maintenance and spread of the opisthorchiasis focus in the middle Ob River basin (Tomsk region, Russia)

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    The study assessed the role of non-commercial cyprinid species in maintaining the opisthorchiasis focus in the middle Ob River basin, Tomsk region, Russia. The source of O. felineus infection for humans and carnivores is fish of the family Cyprinidae. This is the most numerous family, 14 species live in the middle Ob River basin, which includes 6 commercial species and 8 non-commercial species. This study aimed to investigate the current situation on infestation of non-commercial cyprinids with O. felineus metacercariae and their role in maintaining and spreading the natural focus of opisthorchiasis in the middle Ob River basin. We investigated 4 non-commercial species (tench, sunbleak, common bleak, gudgeon), which are highly abundant in water bodies. Tench, common bleak and gudgeon are objects of amateur fishing. These species are traditionally included in the diet of the local population. Opisthorchis felineus metacercariae were recorded in muscles of all the examined fish species. The identification of metacercariae was confirmed by morphological methods and PCR diagnostics. Tench and sunbleak are the main sources of opisthorchiasis infection in the floodplain lakes of the Ob River basin (the prevalence of tench infection is 89.3% and mean intensity of infection is 11.2 metacercariae per fish, the prevalence of sunbleak infection is 50.9% and the intensity of infection is 4.25 metacercariae per fish). The prevalence of infection in the introduced common bleak from the rivers of the middle Ob River basin is rapidly increasing from 2.4 (2016-2018) to 37.5% (2020-2021), and mean intensity of infection increased from 1 to 4.15. The epizootic state of water bodies in the middle Ob River basin remains unfavorable in relation to opisthorchiasis. Tench, common bleak and sunbleak, along with ide and dace, are the main source of infection for humans and animals, which is evidenced by high infection with Opisthorchis felineus metacercariae in these numerous fish species. They pose the greatest danger of infection of people and animals with opisthorchiasis. These species should be included in the campaign to avoid raw and poorly cooked fish in the diet. In addition, such species as roach, bream and sunbleak also pose the danger of infection with opisthorchiasis, but to a lesser extent

    Electrochemically induced phosphorylation of alkenes

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    The processes of electrochemical phosphorylation of alkenes were investigated. It was found that anodically generated radical-cations of trialkyl phosphites, dialkyl trimethylsilyl phosphites, mono-and diamidophosphites were added to olefin molecules to give unsaturated alkenephosphonates. The anodic oxidation of tetraalkyl pyrophosphites proceeds with disintegration of initial radical-cations and leads to mixture alkane-and alkenephosphonates. Greater amounts of alkanephosphonates were formed during anodic oxidation of sodium (or lithium) dialkyl phosphites in the presence of alkenes. © 1997 Published by Elsevier Science Ltd

    Development of a stable eukaryotic strain producing fully human monoclonal antibody on the basis of the human antibody against ectromelia virus

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    Fully­human antibodies have a great therapeutic importance; however, the development of stable strains providing a high level of production of full­size antibodies is a challenging task, as antibody molecules contain two types of polypeptide chains. To develop the producing strain, random integration of the plasmid containing the gene encoding the target protein into the genome of the host cells is commonly used. The aim of this study was the development of an original expression system, using gene targeting to integrate the gene encoding the fully­human antibody into the transcriptionally active region of the genome of eukaryotic suspension cells CHO­S. To develop a stable strain, the cassette vector plasmid pCDNA5/FRTDHFR­CH­CL containing the site of homologous recombination and the genes encoding heavy and light chains of the fully human antibody of the IgG1/kappa class was constructed at the first step. Notably, DNA of the plasmid pCDNA5/FRT­DHFR­CH­CL was organized in such a way that the restriction sites for rapid cloning of DNA fragments encoding the variable domains of heavy and light chains were inserted upstream of the sequences encoding constant domains of the heavy and light chains of the antibody. Secondly, DNA fragments encoding the variable domains of the heavy and light chains of antibody against orthopoxvirus protein p35 were inserted into the pCDNA5/FRT­DHFRCH­CL cassette plasmid. Then, CHO­S/FRT cells, which contain the FRT­site for homologous recombination and are able to produce green fluorescence protein GFP, were transfected with the constructed plasmid. After the insertion of the target genes into the FRT­site, GFP production was supposed to stop. Using this selection system, a stable clone producing target antibody fh8E was selected with the level of production of about 100 μg/ml. The binding affinity of purified antibody fh8E with the targeted protein, measured by surface plasmon resonance, was 12 nM. In addition, antibody fh8E demonstrated anti­vaccinia virus activity in the plaque reduction neutralization test in vitro

    The results of treatment of chronic recurrent aphthous stomatitis by gel containing zero-valent silver

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    The article presents the results of complex treatment of chronic recurrent aphthous stomatitis by methylcellulose-based gel with arabinogalactan biocomposite containing zero-valent silver in nano-valent condition. The gel was applied 3-6 times a day at the prescription of Diquertin 0,06 g 3 times a day and Fibrolar 0,3g 3 times a day. The proposed method of treatment allows to improve the effectiveness of treatment by increasing remission and reducing treatment terms

    Taxonomic composition and biodiversity of the gut microbiome from patients with irritable bowel syndrome, ulcerative colitis, and asthma

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    To date, the association of an imbalance of the intestinal microbiota with various human diseases, including both diseases of the gastrointestinal tract and disorders of the immune system, has been shown. However, despite the huge amount of accumulated data, many key questions still remain unanswered. Given limited data on the composition of the gut microbiota in patients with ulcerative colitis (UC) and irritable bowel syndrome (IBS) from different parts of Siberia, as well as the lack of data on the gut microbiota of patients with bronchial asthma (BA), the aim of the study was to assess the biodiversity of the gut microbiota of patients with IBS, UC and BA in comparison with those of healthy volunteers (HV). In this study, a comparative assessment of the biodiversity and taxonomic structure of gut microbiome was conducted based on the sequencing of 16S rRNA genes obtained from fecal samples of patients with IBS, UC, BA and volunteers. Sequences of the Firmicutes and Bacteroidetes types dominated in all samples studied. The third most common in all samples were sequences of the Proteobacteria type, which contains pathogenic and opportunistic bacteria. Sequences of the Actinobacteria type were, on average, the fourth most common. The results showed the presence of dysbiosis in the samples from patients compared to the sample from HVs. The ratio of Firmicutes/Bacteroidetes was lower in the IBS and UC samples than in HV and higher the BA samples. In the samples from patients with intestinal diseases (IBS and UC), an increase in the proportion of sequences of the Bacteroidetes type and a decrease in the proportion of sequences of the Clostridia class, as well as the Ruminococcaceae, but not Erysipelotrichaceae family, were found. The IBS, UC, and BA samples had signif icantly more Proteobacteria sequences, including Methylobacterium, Sphingomonas, Parasutterella, Halomonas, Vibrio, as well as Escherichia spp. and Shigella spp. In the gut microbiota of adults with BA, a decrease in the proportion of Roseburia, Lachnospira, Veillonella sequences was detected, but the share of Faecalibacterium and Lactobacillus sequences was the same as in healthy individuals. A signif icant increase in the proportion of Halomonas and Vibrio sequences in the gut microbiota in patients with BA has been described for the f irst time

    Genetic characterization of clinical <I>Klebsiella</I> isolates circulating in Novosibirsk

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    72 clinical strains of Klebsiella spp. isolated from samples obtained from humans in Novosibirsk, Russia, were analyzed. Species identification of strains was performed using 16S rRNA and rpoB gene sequences. It was revealed that Klebsiella pneumoniae strains were dominant in the population (57 strains), while the remaining 15 strains were K. grimontii, K. aerogenes, K. oxytoca and K. quasipneumoniae. By molecular serotyping using the wzi gene sequence, K. pneumoniae strains were assigned to twenty-one K-serotypes with a high proportion of virulent K1- and K2-serotypes. It was found that K. pneumoniae strains isolated from the hospitalized patients had a higher resistance to antibiotics compared to the other Klebsiella species. Real-time PCR revealed that the population contained genes of the blaSHV, blaTEM, blaCTX families and the blaOXA-48 gene, which are the genetic determinants of beta-lactam resistance. It has been shown that the presence of the blaCTX sequence correlated with the production of extended-spectrum beta-lactamases, and phenotypic resistance to car-bapenems is due to the presence of the blaOXA-48 gene. At the same time, the carbapenemase genes vim, ndm, kpc, imp were not detected. Among the aminoglycoside resistance genes studied, the aph(6)-Id and aadA genes were found, but their presence did not always coincide with phenotypic resistance. Resistance to fluoroquinolones in the vast majority of strains was accompanied by the presence of the aac(6’)-IB-cr, oqxA, oqxB, qnrB, and qnrS genes in various combinations, while the presence of the oqxA and/or oqxB genes alone did not correlate with resistance to fluoroquinolones. Thus, the detection of blaCTX and blaOXA-48 can be used to quickly predict the production of extended-spectrum beta-lactamases and to determine the resistance of Klebsiella to carbapenems. The detection of the aac(6’)-Ib-cr and/or qnrB/qnrS genes can be used to quickly determine resistance to fluoroquinolones

    ANALYSIS OF DOMAIN SPECIFICITY OF THE PROTECTIVE CHIMERIC ANTIBODY ch14D5a AGAINST GLYCOPROTEIN E OF TICK-BORNE ENCEPHALITIS VIRUS

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    A drug for the prevention and therapy of tick-borne encephalitis virus is being developed on the basis of the protective chimeric antibody ch14D5a. At the same time, the epitope recognized by this antibody on the surface of glycoprotein E has not been localized yet. The aim of this work was to identify the domain of glycoprotein E, to which the protective antibody ch14D5a binds. As a result, four recombinant variants of glycoprotein E were generated using the bacterial expression system: (1) the rE protein containing the domains D1, D2, and D3 of glycoprotein E; (2) the rED1+2 protein containing domains D1 and D2; (3) the rED3_301 protein, which is domain D3 of glycoprotein E, and (4) the rED3_294 protein comprising domain D3 and a hinge region connecting domains D1 and D3. The rED3_294 and rED3_301 proteins were obtained in soluble monomeric form. The rE and rED1+2 proteins were extracted from the inclusion bodies of Escherichia coli. Using Western blot analysis and surface plasmon resonance analysis, it was demonstrated that the protective chimeric antibody ch14D5a and its Fab fragment bound specifically to domain D3 of glycoprotein E. Since the antibodies recognizing epitopes on the surface of domain D3 do not tend to cause antibody-dependent enhancement of the infection as compared to antibodies directed to domains D1 and D2, the data obtained confirm the promise of using the antibody ch14D5a in the development of a therapeutic preparation against the tick-borne encephalitis virus

    Non-universal equilibrium crystal shape results from sticky steps

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    The anisotropic surface free energy, Andreev surface free energy, and equilibrium crystal shape (ECS) z=z(x,y) are calculated numerically using a transfer matrix approach with the density matrix renormalization group (DMRG) method. The adopted surface model is a restricted solid-on-solid (RSOS) model with "sticky" steps, i.e., steps with a point-contact type attraction between them (p-RSOS model). By analyzing the results, we obtain a first-order shape transition on the ECS profile around the (111) facet; and on the curved surface near the (001) facet edge, we obtain shape exponents having values different from those of the universal Gruber-Mullins-Pokrovsky-Talapov (GMPT) class. In order to elucidate the origin of the non-universal shape exponents, we calculate the slope dependence of the mean step height of "step droplets" (bound states of steps) using the Monte Carlo method, where p=(dz/dx, dz/dy)$, and represents the thermal averag |p| dependence of , we derive a |p|-expanded expression for the non-universal surface free energy f_{eff}(p), which contains quadratic terms with respect to |p|. The first-order shape transition and the non-universal shape exponents obtained by the DMRG calculations are reproduced thermodynamically from the non-universal surface free energy f_{eff}(p).Comment: 31 pages, 21 figure

    Production of {\pi}+ and K+ mesons in argon-nucleus interactions at 3.2 AGeV

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    First physics results of the BM@N experiment at the Nuclotron/NICA complex are presented on {\pi}+ and K+ meson production in interactions of an argon beam with fixed targets of C, Al, Cu, Sn and Pb at 3.2 AGeV. Transverse momentum distributions, rapidity spectra and multiplicities of {\pi}+ and K+ mesons are measured. The results are compared with predictions of theoretical models and with other measurements at lower energies.Comment: 29 pages, 20 figure
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