Molecular Genetic Research Methods Research Articles

Milk productivity of simmental cattle by combined kappacasein and somatotropin genes

The economically important productive traits of cattle that contribute to the development of the dairy industry are considered to be abundant milk yield, protein and fat content in milk. In recent years, breeders have focused their attention on cattle breeding programmes based on molecular genetic research methods. The potential of animal productivity largely depends on genetic variants of marker genes present in the genotype of an individual. The genes of kappa-casein and somatotropin are considered to be promising DNA markers, as they are responsible for qualitative and quantitative traits of cattle productivity. In this work we studied milk productivity of 84 cows of Simmental breed from the breeding plant in the Urals by kappa-casein and somatotropin genes, as well as by complex genes. On the gene kappa-casein on milk yield in advantage are individuals with genotypes CSN3AB 6937,6 kg. The higher content of protein in milk, milk fat and protein yield, as well as the sum of nutrients were recorded in cows with CSN3BB genotypes 3.40%, 282.5 kg, 234.2 kg and 516.7 kg, respectively. In terms of somatotropin gene, cows with GHVV genotypes had the most abundant milk production 7160.0 kg. In terms of protein-milk yield, coevals with GHLL genotypes are more productive 3.4 %. The sum of nutrients, milk fat and protein yield is more established in milk of cows with GHVV genotypes 522.7 kg, 293.6 kg and 229.1 kg, respectively. All nine possible variants of complex genotypes for kappa-casein and somatotropin genes occur in this Simmental herd: AA/LV 26 cows; AA/LL 14; AA/VV 12; AB/LL 13; AB/LV 10; AB/VV 2; BB/LL 4; BB/ VV 2; BB/LV 1. Data processing on the effect of complex genotypes on milk productivity included a number of 10 cows or more. Higher milk yield, milk protein content, milk fat and protein yield, and nutrient sum were found in AB/LL complex genotypes: 6756.0 kg, 3.4 %, 277.0 kg and 229.7 kg, 506.7 kg, respectively. Significant differences were found between cow groups in the content of mass fraction of protein.

The frequency of detected pathogen genomes in children with acute respiratory infections

Due to the high prevalence of acute respiratory infections in children, it was of interest to determine the composition of bacterial and viral-bacterial associations for respiratory tract inhabiting microorganisms. To identify respiratory tract pathogens, especially viruses and unculturable bacteria, it is advisable to use molecular genetic research methods particularly PCR. The work was aimed at comparatively analyzing rate of genome detection for respiratory tract pathogens in children with acute respiratory infections and apparently healthy controls. Materials and methods. Children (97 people) were examined, of which 35 people — with acute respiratory infections of the upper respiratory tract (nasopharyngitis, pharyngitis, laryngitis) (ARI URT), 32 people — with acute respiratory infections of the lower respiratory tract (acute bronchitis, acute obstructive bronchitis) (ARI NDP) and 30 people — apparently healthy control at the time of examination. RNA and DNA of viral and bacterial pathogens were assessed in the oropharyngeal smears using PCR. Test systems produced by the Federal Budgetary Institution Central Research Institute of Epidemiology of Rospotrebnadzor and JSC Vector-Best were used. Results. An analysis of detection rate for DNA and RNA of bacterial and viral pathogens showed the presence of a wide range of them (20 different species/strains out of 27 identified) in oropharyngeal biomaterial from all examined children. The peak diversity and detection rate of pathogen genomes were found in apparently healthy subjects and children with ARI UDP (DNA of members from Herpesviridae family, S. pneumoniae, H. influaenzae, MSSA, MRCoNS). Associations of 4–6 pathogens prevailed in the microflora, and the “core” of both bacterial and viral-bacterial associations was the combination of S. pneumoniae and H. influenzae (in 93.3% and 60.0% of cases, respectively). In bacterial associations, staphylococci (MRSA and MRCoNS) and P. aeruginosa were also detected in healthy children, MSSA and other very rarely bacterial types were detected in children with ARI UDP. In children with NPD infections, the majority of whom (75.0±7.7%) were classified as long-term ill and had a complicated disease course, a noticeable depletion (decrease in taxonomic diversity) of the nasopharyngeal microbiota was found. Conclusion. The presented data indicate the presence in the biomaterial of the examined children of molecular genetic markers of a wide range of pathogens presented as viral-bacterial and bacterial associations, with varying composition being related to patient clinical status. Detection of pathogen genomes is important for choosing proper etiotropic therapy at early disease stages as well as prescribing probiotic drugs that can restore a balance in respiratory tract microflora.

Syndromic obesity in children (using the example of clinical cases)

Obesity is a heterogeneous group of hereditary and acquired diseases associated with excessive accumulation of adipose tissue in the body. One example of syndromic obesity in children is Bardet-Biedl syndrome. This is a rare autosomal recessive disease from the group of ciliopathies, characterized by retinal dystrophy, obesity, polydactyly, mental retardation, hypogonadism, and renal dysfunction. The article presents two clinical cases of Bardet-Biedl syndrome. Diagnostic criteria for the disease are given, and the need for molecular genetic research methods in the early stages of the diagnostic search is shown. Promising directions in the treatment of the syndrome are considered.

Possibilities of using nested PCR-RFLP for taxonomic identification of L3 larvae of the family Trichostrongylidae, Leiper, 1912

The purpose of the research is to apply molecular genetic research methods to identify the taxonomic affiliation of gastrointestinal parasitic sheep nematodes of the family Trichostrongylidae using nested PCR followed by the restriction fragment length polymorphism (RFLP) analysis.Materials and methods. Parasitic nematodes, L3 Strongylata larvae obtained from incubated fecal samples of sheep. The genomic DNA was isolated using a commercial kit for DNA extraction from micro-quantities of tissues (Synthol, Moscow) as per the manufacturer’s guidelines. For DNA amplification, a T-100 Bio-Rad thermal cycler and a commercial Eurogen Master Mix reagent kit were used. The PCR regime was performed according to the WAAVP guidelines, 2006. The restriction endonuclease Rsa I of amplified Trichostrongylidae fragments was performed according to guidelines of the enzyme manufacturer (Sibenzyme, Novosibirsk).Results and discussion. To determine the taxonomic affiliation of Strongylata larvae isolated after incubation of feces from sheep, molecular genetic studies were performed using nested PCR followed by the restriction fragment length polymorphism (RFLP) analysis. This method makes it possible to identify, with the least effort, the genotypes of three species of Strongylata Haemonchus contortus, Trichostrongylus colubriformis, and Teladorsagia circumcincta at the larval stage.

Assessing molecular genetic and immunological predictors of COVID-19 course in healthcare worker risk group

Relevance. Studying features of innate and adaptive mechanisms of immune response in medical workers (MW), the most vulnerable social group with a high risk of infection, is an urgent research task. The aim of the study: Comprehensive study of innate and adaptive immune mechanisms and analyzing relationships between clinically significant polymorphisms (SNPs) in TLR2, TLR4 genes, TLR2 expression level on peripheral blood monocytes, peripheral blood cytokine profile (IL-1β, IL-10, IL-6, IFNγ, platelet activation marker) and SARS-CoV-2-specific humoral immune response in medical workers (MW) at a temporary infectious disease hospital in early and late COVID-19 convalescence. Materials and methods. immunologic, cytofluorimetric and molecular-genetic research methods were applied. Adaptive immune response in medical workers — COVID-19 convalescent subjects. Results. Early post-COVID-19 convalescence period in MW was linked to higher TLR2 monocyte expression; the mean fluorescence intensity was significantly elevated by 1.5-fold compared to control group. Late convalescence period (7 months post-COVID-19) was characterized by lowered serum IFNγ level. A decline in IFNγ production was significant: decreased by 82-fold in MR that was markedly stronger compared to control group (59 times). The imbalance of cytokines controlling antiviral innate and adaptive immune response was revealed in MW with identified combination of polymorphisms rs5743708 and rs4986790 in TLR2, TLR4 genes with the rate not exceeding 6.7%. It was found that 7 months after COVID-19 there was a markedly decreased IFNγ, IL-1β and IL-10 levels. The studies indicate both altered innate and adaptive immune mechanisms and a need to optimize therapeutic and prophylactic measures aimed at increasing patient-intrinsic resistance, protection of respiratory tract mucosal barriers and identification of genetic predictors of defects in innate and adaptive immune response in medical workers — COVID-19 convalescent subjects.

Морфофункциональные изменения СОЖ откормочных свиней при хеликобактериозе

Abstract. The purpose is to study the features of morphofunctional changes in the gastric mucosa of fattening pigs in gastric ulcer disease and to establish a possible correlation between pathological changes and colonization of the gastric mucosa of H. suis. Methods. The study is based on pathoanatomic, microscopic, molecular genetic and histological research methods. Results. In 86 % of cases, significant pathomorphological changes in the gastric mucosa of pigs were detected during a pathoanatomical autopsy. Spiral-shaped microorganisms in smears were found in 28 %, H. suis DNA on the gastric mucosa – in 76 %. In the examined samples in which H. DNA was found. suis in the gastric mucosa, 76.3 % revealed various pathologies in the esophagus, 92% revealed various pathologies on the gastric mucosa. In 24 %, when H. suis DNA was not detected, 33.3 % showed no visible damage and 66.7 % revealed various pathologies. The results of the correlation between morphological changes in the gastric mucosa and its infection with helicobacter reached the limits of statistical reliability. Histological methods revealed that active chronic gastritis was detected in 48.0 %, inactive chronic gastritis was detected in 34.0 % and the norm (almost the norm) was found in 8.0 %. Chronic gastritis during exacerbation was reliably diagnosed in 55.2 % of cases when H. suis DNA was detected on the gastric mucosa. Chronic gastritis during remission was diagnosed in 34.2 % of cases when H. suis DNA was detected on the gastric mucosa. The results presented in the work reflect the undoubted connection between the presence of H. suis and the development of gastritis in pigs.

Hospital environment microbiome

The aim of the review is to give a brief description of the biodiversity and structure of the hospital environment microbiome based on molecular genetic research methods. Until a certain time, studies of the hospital environment microbiota for the purposes of epidemiological surveillance and control of healthcare-associated infections (HAIs) were based on routine microbiological identification of clinically relevant bacterial taxa. Discovery of DNA, the development of sequencing technologies, PCR and cloning techniques enabled the investigation of microbial communities using cultivation-independent, DNA and RNA-based approaches. At the current level of knowledge, the hospital environment can be considered as a superorganism with its own microbiome. Multiomic technologies, including meta-transcriptomic, meta-proteomic and metabolomic approaches, provide detailed information about microbial activity in the environment. Now it has been established that there is a stable core of the hospital microbiome where the vast majority of microorganisms are necessary for the functioning of the hospital ecosystem and are not classified as human pathogens. The hospital microbiome has a homogeneous structure composed by a massive dominance of a few taxa and microbial network with low connectivity forming a clustered topology. A keystone species is a taxon whose importance for maintaining community structure is relatively higher than others and its identification is of paramount importance. Due to the lack of knowledge of the hospital environment microbiome by molecular genetic technologies, there is no single shared point of view on the microbial diversity in different healthcare facilities. But there is no doubt that molecular genetic technologies will shed light on the evolution of hospital strains and determine which indicators are the most informative for monitoring and prognosis of HAIs.

РОЛЬ МОЛЕКУЛЯРНО-ГЕНЕТИЧЕСКИХ МЕТОДОВ ИССЛЕДОВАНИЙ В ЭТИОПАТОГЕНЕЗЕ ОСТЕОМИЕЛИТА ЧЕЛЮСТЕЙ

The subject of the study is the importance of molecular genetic research methods in the study of the etiopathogenesis of osteomyelitis of the jaws. The purpose of the work is to provide up-to-date information to researchers, dental surgeons, and maxillofacial surgeons on the possibilities of molecular genetic research in identifying bacterial pathogens in osteomyelitis of the jaws, as well as to reflect genetic markers of pathogenicity factors for a number of the main causative agents of the disease. Methodology. International scientific databases PubMed, ScienceDirect, Scopus, Cochrane Collaboration, Elsevier, as well as electronic catalogs eLIBRARY.RU and CyberLeninka.ru were used. Results. A review of publications demonstrated that S. aureus and S. Epidermidis dominate the etiological spectrum of causative agents of bone tissue infections. The participation of these microorganisms is determined by a whole range of pathogenicity factors. Toxins and Panton-Valentine leukocidin (PVL) genes play a major role in the pathogenesis of osteomyelitis and disease progression. It has been shown that the pathogenic bacteria Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans are capable of inducing differentiated production of cytokines. The most attention has been attracted to E. faecium, which exhibits multidrug resistance to a wide range of antibiotics. The proportion of infections mediated by S. epidermidis and S. Saprophyticus is, on average, about 25% of cases. The proportion of representatives of gram-negative flora Escherichia, Klebsiella, Enterobacter, Citrobacter, Proteus, Providencia, Serratia reaches 23% of cases. Pathogenic nosocomial strains of P. aeruginosa are also involved in the formation of chronic inflammation in osteomyelitis. According to the results of published studies, more than a third of cases of chronic osteomyelitis are mediated by microbial associations, which are dominated by S. aureus, S. epidermidis and, less commonly, E. faecalis. Conclusions. The use of PCR analysis to identify the causative agents of osteomyelitis and gene amplification using specific primers has a huge advantage over routine microbiological tests, being an informative method for studying the pathogenicity factors of the main pathogens. The high importance of molecular genetic methods in the study of the etiopathogenesis of osteomyelitis of the jaws requires their widespread use in the clinic of surgical dentistry and maxillofacial surgery to successfully solve complex problems in the rehabilitation of patients with this disease.

Эпидемиологические аспекты формирования новых рисков заболеваемости и лечения туберкулеза среди населения.

In accordance with the instruction of the Minister of Health of the Russian Federation No. 19 dated 02/07/2023, specialists currently face several important tasks: from 2015 to 2025, to reduce the incidence of tuberculosis, as well as the number of deaths from tuberculosis by 75%. To do this, it is necessary to identify all the risk factors that may create difficulties in achieving these goals. Purpose of the study is to characterize the epidemiological aspects of the formation of new risks of morbidity and treatment of tuberculosis among the population. Materials and methods. An analysis was carried out among newly identified patients with tuberculosis by molecular genetic (n=1682) and bacterial (n=1630) research methods in the period from 2017 to 2020 according to drug resistance indicators. Results. It was found that in the period from 2015 to 2017, the indicators of drug resistance in tuberculosis patients were almost at the same level. The leading antimicrobial drugs in demand among the population were ceftriaxone, azithromycin, levofloxacin, moxifloxacin. The maximum increase in sales in 2020 relative to 2019 data to 150% was determined among quinolone derivatives of moxifloxacin and levofloxacin, which began to be used in the treatment of coronavirus infection. At the same time, these drugs are traditionally used to treat tuberculosis, but in 2020, an alarming trend was revealed, which was that drug resistance was detected in patients with tuberculosis to these drugs. Among newly diagnosed tuberculosis patients, from 2018 to 2020, an increase in the proportion of patients with primary drug resistance to levofloxacin and moxifloxacin was established by 189-480%; whereas for other antibiotics, the increase averaged up to 60.8%. Findings. The findings suggest an alarming scenario in which drug resistance develops towards highly virulent and highly resistant to antibacterial drugs genotypes.

РАСПРЕДЕЛЕНИЕ ГЕНОТИПОВ ГЕНА SLC2A9, УРОВЕНЬ МОЧЕВОЙ КИСЛОТЫ И МЕТАБОЛИТЫ ПУРИНОВОГО ОБМЕНА У ПАЦИЕНТОВ С АРТЕРИАЛЬНОЙ ГИПЕРТЕНЗИЕЙ И ФИБРИЛЛЯЦИЕЙ ПРЕДСЕРДИЙ

The aim is to investigate the frequency of genotypes and alleles of the SLC2A9 gene rs734553 polymorphism, the level of serum uric acid (sUA) and metabolites of purine metabolism in patients with arterial hypertension (AH) and atrial fibrillation (AF), as well as in healthy individuals. Material and methods. The study included 154 patients: 50 were healthy individuals (group 0), of which 22 (44%) were men and 28 (56%) were women aged 50 [45;53] years and 104 were patients with AH and AF (main group), of which 94 (90.4%) were men and 10 (9.6%) were women aged 55 [45; 61] years. The main group was divided into subgroups: subgroup I – patients with AF without a history of AH and other rhythm disorders (n=13); subgroup II – patients with AH in combination with AF (n=68); subgroup III – patients with AH without a history of AF or other rhythm disturbances (n=23). Hyperuricemia was detected in 34 (22.1%) patients, normal uric acid levels were revealed in 120 (77.9%) patients. All patients were studied using clinical, laboratory, instrumental and molecular genetic research methods. The level of sUA was determined by the enzymatic colorimetric method. Serum xanthine oxidase was measured using a method based on a solid phase sandwich-type enzyme-linked immunosorbent assay. Metabolites of purine metabolism in blood plasma were measured using the method of high-performance liquid chromatography. The SLC2A9 gene rs734553 polymorphism was determined using the polymerase chain reaction with real-time detection of results. Results. The patients with AH and AF, as compared to healthy individuals, had more severe disturbances of purine metabolism, characterized by higher concentration of sUA (330 [283; 412] µmol/l and 197 [161; 229] µmol/l (p<0.001), respectively). Also, in contrast to the group of healthy individuals, the group of patients with AH and AF demonstrated an increase in the level of adenosine (p=0.001), and a decrease in the levels of hypoxanthine and xanthine (p<0.001). There were no statistically significant differences in xanthine oxidase activity level (p>0.05), however, in 54% of patients in the main group it was higher than normal values. The dominant allele A and the dominant genotype A/A of the SLC2A9 gene rs734553 polymorphism (75%, p=0.005; 64%, p=0.001, respectively) occurred significantly more often in healthy individuals, while the recessive allele C and the heterozygous genotype A/C were found significantly more often in the group of patients with AH and AF (41.3%, p=0.005; 48.1%, p=0.003, respectively). The C/C genotype (41.7%, p=0.001) was significantly more common in patients with AH in combination with AF and hyperuricemia, compared to patients with AH combined with AF without hyperuricemia as well as healthy individuals (6.8%; 14%, p=0.001, respectively). Patients with AH in combination with AF and the C/C genotype were characterized by a significantly higher level of sUA (p=0.003) compared to patients with the A/A genotype. Conclusions. A statistically significant predominance of the recessive allele C of the SLC2A9 gene rs734553 polymorphism was established in patients with AH and AF compared with healthy individuals (p=0.005). In patients with AH in combination with AF and hyperuricemia, the C/C genotype was significantly more common (41.7%, p=0.001). Patients with AH in combination with AF and the C/C genotype were characterized by a significantly higher level of sUA (p=0.003) compared to patients with the A/A genotype.

Analysis of polymorphism and development of a molecular-genetic system for genotyp-ing by the telomerase reverse transcriptase (TERT) gene

This article explores the genetic variability of the gene that encodes telomerase reverse transcriptase (TERT), which plays a key role in maintaining telomere length and, as a result, genome stability in various eukaryotic species. The study employs a comprehensive approach that combines phylogenetic and bioinformatic analysis with molecular-genetic research methods. The research involved the screening of genetic databases to investigate TERT gene orthologues across organisms belonging to different systematic groups. The TERT gene, which is prevalent in a wide range of eukaryotic biological species, exhibits polymorphisms that have the potential to influence TERT enzyme function and, consequently, animal phenotypes. The primary focus of this study centers on the pig TERT gene, selected as a model organism due to its genetic similarity to humans and its importance as a productive agricultural species. The article explores the exon-intron structure of the TERT gene, analyzing the size of the corresponding transcript and protein product. Furthermore, it provides data on polymorphisms in the pig TERT gene, including missense and synonymous variants. The chromosomal localization of these polymorphisms is characterized and correlated with the domain structure of the TERT enzyme. For the evaluation of the impact of polymorphisms on the structural and functional properties of the TERT enzyme, a molecular-genetic system based on the PCR-RFLP method has been developed. This PCR-RFLP system serves as a basis for subsequent experimental analyses of missense and synonymous variants in population and association studies, allowing for an assessment of the prevalence of these polymorphisms and their significance for animal phenotypes. Given the significance of further laboratory investigation of the pig TERT gene, the developed PCR-RFLP system becomes necessary for the assessment of the functional implications of the polymorphisms within this gene and the potential identification of causative ones among them. The synergy of bioinformatics and molecular-genetic methods in this study lays the groundwork for future impactful research in this field. The presented study holds promise for marker-associated selection, as it opens the way for the use of the TERT gene as a marker in the genetic improvement of agricultural animal species.

Features of the profile of drug resistance to first-line and second-line anti-tuberculosis drugs in patients with human immunodeficiency virus infection

BACKGROUND: Drug resistance to anti-tuberculosis drugs directly affects the disease course. However, a high percentage of multidrug resistance in patients with HIV infection not only worsens the disease course but also forces the development of new strategies for managing such patients.
 AIMS: To characterize drug resistance to anti-tuberculosis drugs in patients with HIV infection.
 MATERIALS AND METHODS: The study recruited patients with newly diagnosed tuberculosis by molecular genetic research methods and bacterial research methods in the Orenburg Regional Clinical Tuberculosis Dispensary.
 RESULTS: For 20182022, the proportion of people with HIV infection who are resistant to isoniazid by 14.6%, rifampicin by 28.85%, moxifloxacin by 717.39%, and amikacin by 104.25% has increased. The reduction in the choice of drugs and possibility of effective anti-tuberculosis therapy in people with HIV infection are also complicated by the detection of a multidrug-resistant culture in 20.34% of the examined patients and multidrug resistance in 39.6%. In over 5 years, the percentage of gene mutations of mycobacteria responsible for resistance to anti-tuberculosis drugs has increased.
 CONCLUSIONS: The results of this study indicate the need to search for new solutions and prevent resistance to existing anti-tuberculosis drugs and for the development of new drugs effective for use as first- and second-line drugs.

Clinical case of diagnosis of generalized tuberculosis in a child with a positive result of an intradermal test

At present day, generalized forms are rarely found in the structure of tuberculosis in children. A significant risk factor for the development of generalized lesions is prolonged contact with a tuberculosis patient. The diagnosis of a specific etiology is often complicated by the absence of pathognomonic symptoms. Immunodiagnostics, microbiological and molecular genetic research play an important role in the diagnosis of tuberculosis infection in children. The purpose of this study was to analyze the case of the development and diagnosis of generalized tuberculosis in a child of primary school age (7 years and 11 months) with lesions of the lungs, larynx, middle ear. The examination methods included immunological intradermal tests (Mantoux test, RTA test), in vitro test (QuantiFERON-TB), multispiral computed tomography, bronchoscopy and laboratory methods of examination. The manifestation of the disease occurred gradually with the occurrence of hypochromic anemia with a further increase in symptoms of intoxication. A comprehensive examination established a disseminated process in the lungs, larynx and middle ear lesions. Family tuberculosis contact was established when the disease was detected in a child. During the examination, the evaluation result of the Mantoux test showed an increase in sensitivity to tuberculin. The hyperergic result of the RTA test indicated the activity of MBT in the body. At the same time, the irregular conduct of immunodiagnostics using the Mantoux test, the monotony of the test did not allow timely measures to be taken in relation to the in-depth examination of the child for tuberculosis. The specific etiology of the disease was reliably confirmed by cultural and molecular genetic research methods. The child was diagnosed with generalized tuberculosis, disseminated pulmonary tuberculosis in the infiltration phase, MBT (+) with drug resistance to isoniazid, streptomycin, paraaminosalicylic acid, tuberculosis of the larynx and vocal apparatus, PCR (+) with drug resistance to isoniazid, tuberculous right-sided otitis media, MBT (+) with drug resistance to isoniazid, streptomycin, paraaminosalicylic acid. The presented clinical case indicates the need for timely detection of tuberculosis contacts, regular immunodiagnostics, and compliance with phthisiological alertness of doctors of all specialties in relation to children with long-lasting symptoms of various diseases. The complete physical examination using an intradermal RTA test (Diaskintest), microbiological and molecular genetic research methods allows to establish the tuberculous etiology of the lesion.

Founding of the culture collection of antibiotic-resistant strains of zoonotic bacteria in the Russian Federation.

The main purpose of a national bioresource center is to standardize, centralize, preserve, and ensure accessibility of microbial bioresources that accumulate there because of state research programs. The establishment of national bioresource centers for antibiotic-resistant microorganisms allows to solve practical problems in the field of veterinary service, as well as to develop effective chemotherapeutic and disinfectant drugs to overcome the mechanisms of resistance. This study aimed to outline the process of forming a national culture collection of antibiotic-resistant strains of zoonotic bacteria in the Russian Federation using two microbial strains. The object of research was isolates of Salmonella spp., Escherichia coli, Enterococcus spp., Campylobacter spp., Listeria monocytogenes, and Staphylococcus spp., all of which were obtained from biomaterials of farm animals, feed samples, bedding, water from livestock buildings, washouts from environmental objects, and food products. The resistance of bacterial isolates was determined using microbiological and molecular-genetic research methods. During monitoring studies, 1489 bacterial isolates were isolated. In total, 408 bacterial isolates were tested for sensitivity to antimicrobial agents, including E. coli (47.6%), Salmonella spp. (30.4%), Enterococcus spp. (11.3%), and Campylobacter spp. (10.8%). For genetic characterization, 95 isolates of Salmonella enterica, E. coli, Campylobacter spp., L. monocytogenes, Staphylococcus spp., Enterococcus spp. were chosen from the research collection, which was formed as part of the monitoring program for antibiotic resistance. Deposited isolates that underwent whole-genome analysis can be used as positive control samples both in the development and use of methods or test systems for the detection of various resistance genes in zoonotic bacteria. In addition, such isolates can also be used for microbiological studies related to determining the sensitivity of microorganisms to antibacterial drugs, for phenotypic studies in the diagnosis of various bacterial infections in animals and birds, and retrospective analysis of strains from numerous collections.

Development of test systems for the analysis of polymorphism of the TNFAIP3 and CDS1 genes associated with the fat thickness in pigs

Relevance. In pig husbandry, one of the main issue in selection and breeding work is the efficiency of increasing the yield of quality products. The development of molecular genetic research methods using chips of various densities and subsequent genome-wide association studies made it possible to identify a large number of new genes potentially associated with selectively significant traits. Some of these potential genes are the TNFα-induced protein 3 (TNFAIP3) and CDP-diacylglycerol synthase 1 (CDS1) genes. The results of domestic and foreign studies show that these genes are associated with the regulation of the process of catabolism of cellular proteins and differentiation of fat cells.Methods. For further investigation, two polymorphisms were selected that showed a reliable association with the signs: the thickness of the fat over the 6–7 thoracic vertebrae and the thickness of the fat over the 10–12 thoracic vertebrae — in the TNFAIP3 genes (SSC1, rs81351586, A/G) and CDS1 (SSC8, rs331818788, C/A). Polymorphism was determined by real-time PCR. The selection of oligonucleotide probes and primers was carried out based on the localization of the mutation using the BLAST online resource. To test the information content of the developed RT-PCR test systems, alternative primer pairs were selected for RFLP analysis. DNA samples from 50 Large White pigs were used as genetic material.Results. The developed test systems for potential marker genes of productivity TNFAIP3 and CDS1 made it possible to clearly determine the genotypes of animals in the PCR-RT format. Both studied loci were found to be polymorphic. The developed test system can be used for genotyping a large number of animals and selecting animals with certain genotypes.

Current Information on the Diversity of Dinoflagellates of Ukraine

Presenting current information on the diversity of <i>Dinoflagellata</i> in Ukraine. The use of electron microscopy, as well as molecular genetic research methods over the past 10 years have made it possible to observe significant changes in the taxonomic system of the<i> Miozoa</i> division of the superclass <i>Dinoflagellata.</i> Based on the analysis of 216 literary sources and bringing all the names of dinoflagellates in line with those accepted in the international database AlgaeBase, it was established that the current list of <i>Dinoflagellates</i> of Ukraine includes 368 species (395 infraspecific taxa), belonging to 3 classes, 14 orders, 45 families and 98 genera. The number of species found in Ukraine is an order of magnitude lower than that currently known for<i> Miozoa</i> in the world (3636), and their distribution by order almost coincides and is very uneven: 3 orders include 63% of currently known species in the peace and 71% - in Ukraine. The most diverse orders in Ukraine are<i> Peridiniales</i> (118 species, 32%),<i> Gymnodiniales</i> (82/22%) and<i> Gonyaulacales</i> (60/16%). In comparison with the most complete review by Krakhmalnyi (2011), the species richness of dinoflagellates of Ukraine and their taxonomy underwent significant changes in the last decade. The number of species, orders and genera has increased twice and number of new species and infraspecific taxa has increased by 85 units and one species has been described as new to science. But the species diversity of some dinoflagellates regions of Ukraine remains insufficiently studied, and some of them require additional research. The analysis of the distribution of dinoflagellates in the territorial waters of Ukraine confirmed that most of them inhabit the seas (302 species and infraspecific taxa), which is more then to three times higher than in estuaries (112) and is more to twice those in aquatic complexes on the land (134). Overall, 70% were unique (not found in other ecotopes), while 30% were shared. Naturally, most of them were found in the contact zone between seas and estuaries (14/7%), 4/3% - between the estuaries and land water bodies, 3% were found in the seas and in the land water bodies, and 8/1% were found in all studied ecotopes. This shows the high role of the estuaries, as water contact zones, for the dinoflagellates diversity and the necessity for their additional studies. Among the species occurring on the land water bodies, the largest number is assigned to the Dnieper-Black Sea, Middle Dnieper and Carpathian-Danube algofloristic subprovinces, due to the presence of water contact zones of different origins and greater study of these areas.

ВИДОВОЕ БОГАТСТВО ИНФУЗОРИЙ МАЛОГО ЗАБОЛАЧИВАЮЩЕГОСЯ ВОДОЕМА: ОБЩИЕ ПРОБЛЕМЫ СОХРАНЕНИЯ ИХ БИОРАЗНООБРАЗИЯ

This article presents the results of the fi rst study of the species composition of ciliates from the polyhumous lake Mohovoye, located in the Volga-Kama State Natural Biosphere Reserve; discusses the general issues of the need to organize the conservation and protection of protozoa and their habitats; provides a brief overview of the experience accumulated in the world on this issue. The aim of the work was to identify new and rare species of ciliates, to describe their autecological and distributional features as a descriptive basis for further identifi cation of potential diversity. 53 species have been recorded in the deep-water part of the lake, while there are species that have not even been identifi ed to the genus level. Lacrymaria cf. sapropeliсa Kahl, 1927, Trichospira inversa (Claparède & Lachmann, 1858), two species from the family Spathidiidae, as well as the main dominant Pseudoblepharisma tenue var. viride (Kahl, 1926) have not previously been recorded in this region. Their detection is more likely due to the low level of study of such undisturbed habitats than to the endemism of these species. The uniqueness of the lake and the whole complex of ciliates species lies in the signifi cant magnitude of the maximum abundance – 753.7 million cells/m3 ; 53-75% of the abundance was formed by P. tenue var. viride (Kahl, 1926), which is a rare species in other waterbodies. In general, mainly mixotrophic ciliares form a very narrow and high, like a “bacterial plate” abundance maximum. The problem of the conservation of the ciliates biodiversity lies in the underestimation of their importance, due to their inconspicuousness and cosmopolitanism; the low attractiveness of small reservoirs as “pockets of diversity” for limnologists and the lack of well-trained specialists in the systematics of ciliates who can be able to competently combine morphological and molecular genetic research methods.

Molecular genetic and bioinformatic approaches for the allele reconstruction of the <i>rolB/C</i>-like gene in representatives of the genus <i>Vaccinium</i> L.

Agrobacterium mediated transformation is one of the most studied examples of horizontal gene transfer between pro- and eukaryotes. During this process a part of the Ti-plasmid T-DNA is transferred into the plant cell genome. These sequences could be preserved in the genomes during evolution and inherited in a series of sexual generations. Such plants are described within the genus Vaccinium L. [1]. Our research team is currently analyzing natural transgenes in V. oxycoccos L., V. japonicum Miq., V. conchophyllum Rehder, V. emarginatum Hayata, V. myrtilloides Michx., V. virgatum Ait., V. corymbosum L., V. darrowii Camp, V. smallii A. Gray, V. praestans Lamb., V. ovalifolium Sm., V. myrtillus L., V. uliginosum L., V. vitis-idaea L. Previously, analyzing the natural transgenes in another genus (Camellia L.) [2], we showed the importance of reconstructing the allelic states of transgenes for phylogenetic studies. In this paper, we present a comprehensive approach for studying the allelic state of the rolB/C-like gene in plants of the genus Vaccinium. It combines molecular genetic and bioinformatic research methods. Molecular genetic methods involve Sanger sequencing of a gene sequence in a large number of samples, while for each sample the sequence is presented as a set of polymorphic positions in binary form. Allele resolution occurs based on the description of alleles in homozygotes and a series of subtractions of known alleles in heterozygous samples. The second method involves the analysis of SRA (Sequence Read Archive) sequences available in the databases. SRA is a repository of high-throughput sequencing raw data. Based on our work, we can conclude that both of these approaches make it possible to describe the allelic state of the rolB/C-like gene in representatives of the genus Vaccinium. The work was performed using the equipment of the Resource Center of Saint Petersburg State University Development of Molecular and Cellular Technologies with the support of the Ministry of Science and Higher Education of the Russian Federation in accordance with agreement No. 075-15-2022-322 dated 04/22/2022 on the provision of a grant in the form of a subsidy from the Federal budget of the Russian Federation. The grant was provided as part of the state support for the creation and development of the world-class Scientific Center Agrotechnologies for the Future.

RESULTS OF THE STUDY OF RESISTANCE TO CLARITHROMYCIN IN PATIENTS WITH HELICOBACTER PYLORI-ASSOCIATED GASTRIC DISEASES IN UZBEKISTAN

The authors studied the resistance of bacteria to clarithromycin in 194 patients with a positive CagA gene of H. pylori-associated stomach diseases. The study is based on the results of molecular genetic research methods and statistical data. According to the study, the studied population was characterized by the presence of three types of gene mutations in the 23S-rRNA gene: 2142 G, 2142C and 2143 G. Wild type Wt type H. pylori was detected in 58.8% of cases.

Human Сysticercosis caused by <i>Taenia solium, Taenia crassiceps, Taenia hydatigena, Taenia martis</i>

The urgency of the problem of human cysticercosis is due to the widespread prevalence of this disease, polymorphism and the severity of clinical manifestations. The purpose and result of the work is to summarize the available information about the etiology, epidemiology, clinical picture, diagnosis, and treatment of human cysticercosis.Conclusion. Cysticercosis affects several million people worldwide. The clinic depends on the location of the cysticercus. Diagnostics is carried out on the basis of a morphological study of the obtained biomaterial, instrumental, serological and molecular genetic research methods. Albendazole, praziquantel are used as etiotropic therapy. Surgical removal of cysticercus is performed according to indications.