[Functional food ingredient - chromium complex with protein fermentolysate of bivalve Mactra chinensis for the prevention of hyperlipidemia and obesity].

The creation of specialized food systems capable of correcting body weight and influencing lipid metabolism is an urgent task at the present stage. The main way to create such food systems is to modify product profiles (lipid, protein, carbohydrate, mineral, vitamin, etc.). The aim of the study was to obtain and characterize a new food source of an organic form of chromium for the prevention of hyperlipidemia and obesity in the form of a complex with peptide fractions of fermentolysate proteins of the Mactra chinensis bivalve mollusk from the Far Eastern region. Material and methods. Soft food parts of the Mactra chinensis bivalve mollusk from the Far Eastern region (the motor muscle and mantle) were used as objects of research. Mollusk specimens were collected in the Amur Bay in June - September 2022. Biotechnological modification of soft tissue proteins was carried out using alkaline protease protozyme B with the following parameters: the duration of the process - 12 and 24 hours, pH - 7.0-7.2, temperature 55 °C. The fractional composition of proteins and peptides was determined by medium pressure gel permeation chromatography, the molecular weight (MW) of proteins and peptides was calculated using MW markers by comparing retention volumes. Extraction of free amino acids was carried out with 70% ethanol for 24 hours at a temperature of 20 °C, the composition and quantitative content of amino acids were determined by HPLC. The complexation reaction was carried out by adding to the fermentolysate with stirring a 10% aqueous solution of CrCl3×6H2O in a mass ratio of 6.25 × nitrogen in the liquid fraction : chromium (III) chloride = 20:1. Process conditions: temperature 20-25 °C, time 60 min, pH 7.0-7.1. The chromium content was determined by the atomic absorption method using spectrophotometer. Results. The content of low-molecular fractions increased more significantly over time in the mantle fermentolysate. The content of the high-molecular fraction of peptides weighing more than 160 kDa was minimal for both the muscle and the mantle and didn't exceed 1.1%. Low-molecular fractions weighing no more than 18 kDa in the 24-hour fermentolysate accounted for 79.6% for the muscle and 86.9% for the mantle. The obtained fermentolysates were characterized by a high content of the biologically active amino acid taurine - 25.9% (muscle) and 30.05% (mantle) of the total amino acid content. The high content of such essential amino acids as glycine, alanine, leucine, lysine, and the conditionally essential amino acid arginine was also determined. The obtained fermentolysates of soft tissue proteins of the Mactra chinensis were characterized by a fairly balanced amino acid composition. It has been experimentally established that more than 84% of the total chromium content in muscle fermentolysate and 80.9% in mantle fermentolysate was associated with peptide fractions with molecular weights from 24 to 1.4 kDa, and the highest specific chromium content - 1.67 mg/g protein (muscle) and 1.58 mg/g protein (mantle) was determined in the interval fractions with molecular weights of 18.0-12.5 kDa. The minimum specific content of the trace element was established for high-molecular fractions of 160-67 kDa and low-molecular fraction weighing less than 1.4 kDa. Conclusion. Biotechnological modification of soft tissue proteins of the Mactra chinensis bivalve mollusk from the Far Eastern region made it possible to obtain a balanced amino acid composition fermentolysate with a high content of the free biologically active amino acid taurine. Fortification of the obtained fermentolysate with chromium demonstrated high efficiency of its binding to the amino acid and peptide matrices of the protein hydrolysate. The chromium complex with fermentolysate of proteins of the Mactra chinensis bivalve mollusk can be used as a food source of chromium and taurine, including as a functional ingredient in special food systems for the prevention of hyperlipidemia and obesity.

[Effect of microand nanoplastics on the gastrointestinal mucosa and intestinal microbiome].

Worldwide production and use of the polymers has led to intensive environmental pollution with micro- and nanoplastics (MP and NP). Accumulating in ecosystems, MP are transmitted through food chains and enter the human body. The associated health risks are of grave concern and require assessment. The main entry gate for MP/NP supplied with food is the gastrointestinal tract (GIT). Despite the well-established concept of MP/NP toxicity, information about their actual effects on the GIT is contradictory. The aim of the research was to establish the nature and mechanisms of NPs and MPs action on the gastrointestinal mucosa and intestinal microbiome, basing on the literature data. Material and methods. The review was compiled after selecting of 90 documents from major databases including Web of Science, PubMed, Scopus, Elsevier, Springer and Google Scholar (up to March 2023). Results. In animal studies and in vitro models, it was shown that MP/NP affect mucus secretion, its rheological characteristics, and can cause an increase in the permeability of tight junctions of epithelial cells by reducing the expression of zonula occludens protein 1 (ZO-1), occludin and claudin-1, which promotes the penetration of MP through the intestinal wall. Various adsorption layers (coronas) formed on the surface of MPs both abiotically and during transit through the GIT can lead to both increased and reduced toxicity of MPs. Biofilms formed on MP/NP surface create favorable conditions for the activity of pathogenic bacteria and horizontal gene exchange between the components of the biofilm and the intestinal microbiome. Animal experiments have shown an unfavorable effect of MP/NP on the intestinal microbiota and its key metabolites, contributing to the development of dysbiosis. Conclusion. Most data on the effect of MP on the GIT have been obtained using a model object - polystyrene microspheres, which are rarely found in practice. A frequent limitation of the in vitro studies is the discrepancy between used doses (concentrations) of MP and those that may occur when MP are consumed with food. Data on the potential impact of MP/NP on the GIT protective barrier and intestinal microbiota obtained under various experimental conditions are contradictory. Thus, evidence of the impact of MP/NP on the GIT and intestinal microbiota of humans needs further confirmation, which will allow us to move on to the development of a set of measures that can reduce the risks of MP exposure to human health.

Endoparasites of Wild Boars (Sus Scrofa) in Primorsky Krai, Russia.

This study identified helminthic species among wild boars (Sus scrofa) in Primorsky Krai, Russia. In total, 66 fecal samples were taken from wild boars and examined using the floatation-sedimentation method to identify helminths eggs and protozoan cysts. Age and sex were estimated for each host animal investigated. The helminthic fauna of the wild boars examined involved six parasite genera, but 4 are helminths and 2 are protozoans: the nematodes Metastrongylus spp., Trichuris suis, Capillaria sp. and Ascaris suum; and the protozoan parasites Eimeria sp. and Cystoisospora suis. The most prevalent parasite was Metastrongylus spp. (13.6 %) followed by Trichuris suis (7.6 %). The other parasites found were Eimeria sp. (3 %), Ascaris suum (3 %), Capillaria sp. (1.5 %) and Cystoisospora suis (1.5 %). Not found positive correlation between the host's age and sex and the parasite prevalence. This was the first detailed study on helminths infections among wild boars in Primorsky Krai.

Ultrastructure and Morphological Variability of Non-Culturable Forms of Yersinia pseudotuberculosis Bacteria.

One of the mechanisms underlying the appearance of chronic infections is transition of pathogens into a non-culturable state, which is largely associated with the use of antibiotics. We studied ultrastructure of dormant bacteria Yersinia pseudotuberculosis obtained from the vegetative form of strain 512 by inhibition with kanamycin. On the model of the causative agent of pseudotuberculosis we showed that transition of prokaryotes to a dormant state occurs through apoptosis of bacteria. Fragmentation and condensation of chromatin with the formation of electron-dense fibrils, clumps and large conglomerates characteristic of apoptosis were found in the nucleoid zone of the cytoplasm of inhibited bacterial cells. These results are of great importance for understanding the mechanisms of the existence of pathogens in different conditions, as well as for identifying the causative agents of infectious diseases.

Clinical and diagnostic manifestations of tickborne mixed infection in combination with COVID-19.

The coexistence of various pathogens inside the patient's body is one of the poorly studied and current issues. The aim of the study is to identify the relationship between the indicators of complex laboratory diagnostics and the clinical manifestations of a mixed disease during subsequent infection with the SARS-CoV-2 virus using the example of a case of chronic encephalitis-borreliosis infection. Seven blood serum samples were collected from the patient over the course of a year. For the etiological verification of the causative agents of TBE, Lyme disease and COVID-19, the methods of ELISA and PCR diagnostics were used. The patient was diagnosed with Lyme disease on the basis of the detection of IgG antibodies to Borrelia 5 months after the onset of the disease, since she denied the tick bite. In the clinical picture, there was an articular syndrome and erythema migrans. Later, IgG antibodies to the TBEV were found in the blood. Throughout the study, IgM antibodies to Borrelia were not detected. The exacerbation of Lyme disease could be judged by the clinical manifestations of this disease and by the growth of specific IgG antibodies. A feature of this case was that during an exacerbation of the Lyme disease, an infection with the SARS-CoV-2 virus occurred. Treatment (umifenovir, hydroxychloroquine, azithromycin, ceftriaxone) was prescribed, which improved the condition of the underlying disease, decreased joint pain, decreased IgG levels to borrelia. However, during this period, serological markers of TBEV appear: antigen, IgM antibodies, and the titer of IgG antibodies increases. Most likely, this was facilitated by the switching of the immune system to the SARS-CoV-2 virus, with the simultaneous suppression of borrelia with antibiotics and the appointment of hydroxychloroquine, which has an immunosuppressive effect. Despite the activation of the virus, clinical manifestations of TBE were not observed in the patient, which is most likely associated with infection with a weakly virulent TBEV strain. The further course of tick-borne infections revealed the dominant influence of B. burgdorferi in relation to TBEV. Laboratory studies have shown that suppression of the activity of the borreliosis process by etiotropic treatment subsequently led to the activation of the persistent TBEV.

Comparative In Vitro Study of Antiherpetic Activity of Echinochrome A and Product of Its Oxidation Dehydroechinochrome.

The quinoid pigment echinochrome A isolated from the sea urchin Scaphechinus mirabilis, the product of its oxidation dehydroechinochrome, and structurally similar antiviral agent oxolin were tested for their ability to inhibit plaque formation induced by herpes simplex virus type 1 (HSV-1) in Vero cells. The tested compounds showed significant anti-HSV-1 activity, mainly due to their direct effect on viral particles and on virus attachment to cells. The antiviral efficacy of the test compounds increased in the following order: oxolin→echinochrome A→dehydroechinochrome.

[Evolution of pandemic influenza virus A(H1N1)pdm09 in 2009-2016: dynamics of receptor specificity of the first hemagglutinin subunit (HA1).]

INTRODUCTION: The new reassortant of the swine flu virus A(H1N1)pdm09, which emerged in 2009, overcame the species barrier and caused the 2009-2010 pandemic. One of the key points required for the influenza virus to overcome the species barrier and adapt it to humans is its specific binding to the receptors on the epithelium of the human respiratory tract. PURPOSE: Studying the dynamics of changes in receptor specificity (RS) of the HA1 subunit of the hemagglutinin of the influenza A(H1N1)pdm09 virus strains isolated during the period 2009-2016 on the territory of the Russian Federation, and an analysis of the possible impact of these changes on the incidence rates of the population of the Russian Federation of pandemic influenza in certain epidemic seasons. MATERIAL AND METHODS: Standard methods of collecting clinical materials, isolation of influenza viruses, their typing and genome sequencing were used. For the study of RS of influenza A virus (H1N1)pdm09, the method of solid phase sialosidenzyme analysis was used. RESULTS: It is shown that the change in the parameter W3/6 , which characterizes the degree of a2-3 receptor specificity (a2-3-RS) of the influenza virus A(H1N1) pdm09 over a2-6-RS, coincides with the change in the incidence rates of the Russian Federation's pandemic flu in separate epidemic seasons. There is a tendency to increase the affinity of the virus A(H1N1)pdm09 to α2-3 analogs of the sialyl-glycan receptors of the human respiratory tract epithelium - α2-3-sialoglycopolymers (α2-3-SGP), and falls to α2-6-SGP, with the virus showing the greatest affinity for sulfated sialoglycopolymers. DISCUSSION: Screening for RS strains of influenza A (H1N1)pdm09 virus isolated on the territory of the Russian Federation in 2009-2016 revealed a decrease in the affinity of viruses for a2-6-sialosides, especially for 6'SL-SGP, which is probably due to the presence of amino acid substitutions in the 222 and 223 positions of RBS HA1 viruses. Previous studies have shown that the presence of such substitutions correlates with an increase in the virulence of the influenza A virus (H1N1)pdm09 [16, 23]. Probably, the pandemic virus has evolved towards the selection of more virulent pneumotropic variants. CONCLUSION: Monitoring of the receptor specificity of a pandemic influenza virus makes it possible to identify strains with altered RS to the epithelium of the human respiratory tract and an increased ability to transfer from person to person. Change in the period 2009-2016 the W3/6 parameter characterizing the degree of α2-3-RS excess of the influenza A(H1N1)pdm09 virus over α2-6-RS, coincides with the change in the incidence rates of the pandemic influenza population of the Russian Federation in certain epidemic seasons.

Development and evaluation of a RT-qPCR assay for fast and sensitive rabies diagnosis.

Rabies virus is endemic to Russia, among other countries. It is therefore critical to develop a high-quality and high-precision diagnostic procedure for the control and prevention of infection. The main objective of the research presented here was to develop a reliable RT-qPCR assay for rabies diagnostics. For this purpose, a RABV strains from various biological and geographical origins were used. In addition, rabies-positive and rabies-negative samples, as well as nucleic acids from other viruses and DNA extracted from the brain tissues of mice, dogs, cats, bats and humans, were studied using the developed assay. The analytical sensitivity of the assay, as assessed using armored recombinant positive control dilutions, was 103 copies/ml, and the sensitivity measured using characterized strains was between 0.1 LD50/ml and 1.0 LD50/ml. A broad range of RNA from RABV strains circulating in different regions of Russia, as well as RNA from RABV-positive primary brain samples from 81 animals and two humans, was detected using the developed assay. No false-positive or false-negative results were obtained. Given that high analytical and diagnostic sensitivities and a high specificity were verified for this assay, it has high potential as a screening test that may be suitable for the epizootiological monitoring of animals and for the fast postmortem diagnosis of rabies.

[Time course of changes in cytokines (IFN-γ, IFN-α, IL-18, TNF-α) in the treatment of moderate influenza A (H1N1) pdm09 (2013-2016) with oseltamivir (Tamiflu) and umifenovir (Arbidol) alone and in combination with Kagocel]. / Dinamika tsitokinov (IFNγ, IFNα, IL-18, TNFα) pri lechenii srednetiazhelogo grippa A (H1N1) pdm09 (2013-2016 gg.) osel'tamivirom (Tamifliu) i umifenovirom (Arbidol) v monoterapii i v sochetanii s Kagotselom.

AIM: To assess correlation of cytokines levels and therapy regimes a relationship of the time course of changes in the cytokines IFN-γ, IFN-α, IL-18, and TNF-α to the treatment option for influenza A (H1N1) pdm09 with umifenovir (Arbidol) 800 mg/day for 5 days (n=50); oseltamivir (Tamiflu) 150 mg/day for 5 days (n=50); umifenovir (Arbidol) 800 mg/day for 5 days in combination with Kagocel 72 mg/day for 2 days.; 36 mg/day for 2 days (n=50); oseltamivir (Tamiflu) (150 mg/day for 5 days) in combination with Kagocel 72 mg/day for 2 days; 36 mg/day for 2 days (n=50). A comparison group consisted of 30 healthy volunteers. MATERIAL AND METHODS: The state of immunologic reactivity was assessed twice: at admission of the patients to an infectious disease clinic (at 1-3 disease days) and in the early convalescent period (at 7-8 disease days): venous blood samples were collected to determine the concentrations of IFN-γ, IFN-α, IL-18, and TNF-α by a solid-phase enzyme immunoassay. RESULTS: All the patients in the acute phase of influenza A showed a statistically significant increase in the levels of IFN-γ, IFN-α, and IL-18 as compared with the control group. The groups receiving monotherapy in the early convalescent period had a decrease in the IFN-γ, IFN-α, and IL-18 concentrations that could be compensated by the combined use of the immunomodulator Kagocel. No statistically significant changes in the levels of TNF-α were found in the patients of all the groups, but the groups receiving monotherapy exhibited its lower concentrations in the convalescence period. CONCLUSION: The combination of etiotropic antiviral drugs with Kagocel enhances the efficiency of antiviral therapy. Monitoring of antiviral cytokines during the treatment of influenza A is a convenient tool to verify the efficiency of antiviral therapy and needs to be more widely introduced into medical practice.

[Complete genome analysis of the Batai virus (BATV) and the new Anadyr virus (ANADV) of the Bunyamwera group (Bunyaviridae, Orthobunyavirus) isolated in Russia].

Almost complete nucleotide sequences for the S, M, and L segments were obtained for three strains of the Batai virus (Bunyamwera serogroup, genus Orthobunyavirus, Bunyaviridae family). Based on the results of the phylogenetic analysis conducted forthe three genomic segments LEIV Ast507 and LEIV-Ast528 strains were grouped with other European BATV isolates and were found to be almost identical to the strain 42 isolated from Volgograd Region, Russia, 2003. Surprisingly, LEIV-13395 strain isolated from the Aedes sp. mosquitos in Magadan Oblast, 1987, turned out to be a novel genotype inside Bunyamwera serogroup. The highest nucleotide identity levels of LEIV-13395 genomicsegments (86.9%, 80.8%, 79.7% for S, M and L segments respectively) were observed with corresponding segments of the Batai virus.

Evolution of highly pathogenic avian influenza H5N1 virus in natural ecosystems of northern Eurasia (2005-08).

Fifty-four strains of H5N1 highly pathogenic avian influenza (HPAI) virus were isolated from wild birds in the ecosystems of northern Eurasia and from poultry in the south of western Siberia (July 2005), at the mouth of Volga River (November 2005), at Uvs-Nur Lake on the boundary of the Great Lakes Depression in western Mongolia and the Tyva Republic of Russia (June 2006), in the vicinity of Moscow (February 2007), in the southeastern part of the Russian Plain (September 2007 and December 2007), and in the far east (April 2008) of the Russian Federation and were phenotypically characterized and deposited into the Russian state collection of viruses. Complete genome nucleotide sequences for 24 strains were obtained and deposited into GenBank. In all cases when strains were isolated from both wild birds and poultry in the same outbreak these strains were genetically closely related to each other. Until 2008 all HPAI H5N1 strains isolated in northern Eurasia clustered genetically with the viruses from Kukunor Lake (Qinghai Province, China), known as genotype 2.2 or the "Qinghai-Siberian" genotype. The viruses from the Qinghai-Siberian genotype have continued to evolve from those initially introduced into western Siberia in 2005 into two genetic groups: "Iran-North Caucasian" and "Tyva-Siberian." In vitro replication potential (50% tissue-culture infectious dose in porcine embryo kidney) of Qinghai-Siberian strains decreased over time, which could reflect decreasing virulence. Comparison of genome sequences with biological characteristics of the respective strains permitted us to identify point mutations in PB2, PB1, PA, HA, NP, NA, M2, NS1, and NS2 that possibly influenced the level of replication potential. The HPAI H5N1 virus, which penetrated into the south of the Russian Far East in spring 2008, belonged to genotype 2.3.2.