Vol 99, No 1 (2022)

The aim of the study was to analyze genetic characteristics of strains belonging to group A rotaviruses (RVA) circulating in Moscow in 2015–2020, including rare strains non-typeable by polymerase chain reaction (PCR).

Materials and methods. A total of 289 stool samples were tested; the samples were collected from children aged 1 month to 17 years, hospitalized with acute gastroenteritis. Immunochromatography and real-time reverse transcription-polymerase chain reaction (real-time RT-PCR) assays were used for detection of rotaviruses in the samples. The rotavirus genome sequencing was performed using the Sanger technique and nanopore sequencing.

Results and discussion. RVA RNA was detected in 131 clinical samples, and the G/[P] genotype was identified in 125 samples. The general profile showed prevalence of RVA strains with the G9P[8]I1 genotype (37%) followed by G3P[8]I2, G4P[8]I1, G2P[4]I2, G1P[8]I1, and G3P[8]I1 variants (18, 15, 11, 5, and 2%, respectively). Seven (5%) isolates were identified as GxP[8]. In 2015–2020, the region reported a decline in G4P[8]I1 genotype prevalence (from 39% to 9%) and an increase in the proportion of the G9P[8]I1 genotype (from 6% to 37%) as compared to 2009–2014. In 2018–2020, a large number of cases with the previously unknown DS-1-like reassortant strain with the G3P[8]I2 genotype were reported; the above strain has become widely common worldwide in the recent years. Nanopore sequencing was performed to analyze the genome of the G3P[8]I2 strain and the rare G4P[6]I1 strain. It was found that the G4P[6]I1 strain was phylogenetically related to porcine rotaviruses.

Conclusion. In the recent years, the genetic diversity of RVA circulating in the Moscow Region has changed significantly. The obtained results prove the importance of continuous monitoring of rotavirus infection and selective sequencing of RVA genes to fine-tune data of the type-specific real-time RT-PCR. The ever-changing genetic composition of the circulating RVA strains calls for regular optimization of RVA genotyping systems based on real-time RT-PCR. 

Introduction. For more than 10 years, the Tumen Region has been reporting steadily high rates of HIV infection prevalence. Among the groups at risk for HIV infection, a special place is occupied by the group of incarcerated individuals. This group is mostly represented by drug users, men who have sex with men, commercial sex workers. Diseases acquired during imprisonment or exacerbated in a prison setting become a problem not only for released inmates, but also for communities outside the prison system. Epidemiologically, it is critically important to identify the prison-related factors contributing to HIV progression, considering their unequal significance among incarcerated individuals and civilian population.

The aim of the study is to identify and assess the risk factors affecting the HIV epidemic process in the high riskgroup density areas.

Materials and methods. The study was performed using epidemiological study and stepwise logistic regression methods.

Results. Since 2008, the epidemiological situation in prison settings has become increasingly severe, being characterized by higher rates of detection of HIV cases and HIV prevalence among inmates. The situation has also been aggravated by high death rates among HIV-infected inmates. Our study found that the high risk of fatal outcomes in HIV-infected inmates was associated with multiple parameters: the male gender, parenteral (injection drug use) HIV transmission, existing comorbidities – viral hepatitis and thoracic diseases. 

Introduction. Pathologies of the visual organ (keratitis, glaucoma, etc.) occupy a leading place among the causes of vision loss and blindness. According to the literature, the immunopathogenesis of bacterial keratitis is associated with the activation of macrophages and oxygen explosion. The role of these mechanisms in the pathogenesis of primary open-angle glaucoma is not fully understood. There are isolated studies in which the development of this pathology is associated with nitric oxide NO, which is produced by endothelial NO synthase (nos). However, despite numerous studies, the role of immunogenetics in the pathogenesis of glaucoma remains insufficiently researched.

The aim of the study is to explore the association of T786C, C774T, Glu298Asp polymorphic markers of the eNOS gene with development of POAG in residents of the Perm Territory.

Materials and methods. The study was performed using peripheral blood collected from 93 patients with POAG and 96 patients with cataracts. The real-time polymerase chain reaction was performed after the DNA extraction. The frequencies of alleles and genotypes in the study groups were measured using the chi-square (χ2 ) test and Fisher’s exact test. Results with p < 0.05 were seen as statistically significant. The calculated odds ratio and the 95% confidence interval were used to quantify the association between POAG development in patients and the existence of an unfavorable polymorphic marker.

Results. The C774T and Glu298Asp markers did not show any significant differences in the distribution of genotypes and alleles of the eNOS gene. Higher frequencies of the homozygous TT genotype; and lower frequencies of the C allele of T786C polymorphic locus of eNOS gene were detected in patients with POAG.

Conclusion. Polymorphic markers of the eNOS gene can be seen as factors associated with the risk of POAG. 

Introduction. Due to the remaining tense situation on cholera in the world, research continues on the creation of new preventive drugs, as well as ways to increase the immunogenicity of existing anti-cholera vaccines. The combined use of vaccines with immunomodulators and cytokines is successfully used for the specific prevention of various infections, including particularly dangerous ones.

The aim of the work is an experimental study of the effect of immunomodulators on the immunogenic and protective activity of the cholera bivalent chemical vaccine in order to assess the possibility of their use to improve the specific prevention of cholera.

Materials and methods. The parameters of cellular and humoral local and systemic immune response in experimental animals vaccinated and receiving immunotherapy, as well as the effect of immunomodulators on the protective activity of antigens that are part of the cholera bivalent chemical vaccine, were evaluated.

Results. The studies revealed that the use of immunomodulators in combination with the vaccine leads to an increase in the immunogenic properties of antigens. Immunomodulators stimulate the differentiation of CD4⁺- lymphocytes, ensuring the development of an immune response mainly along the humoral pathway, increase the number of B-lymphocytes, antigen-specific antibody-forming cells, as well as secretory immunoglobulin A in the intestines of vaccinated experimental animals. It is shown that the immunomodulator glucosaminylmuramyl dipeptide increases the protective properties of the antigens that are part of the chemical cholera bivalent vaccine. It was the most effective additive, since it protected all the animals included in the experiment from generalized cholera.

Conclusion. The use of immunomodulators in anti-cholera vaccination, especially with glucosaminylmuramyl dipeptide, may be one of the approaches to improving the specific prevention of cholera. 

In general, the characteristic of the genetic diversity of the Epstein-Barr virus (EBV) underlies the study of pathogenesis, targeted development of laboratory diagnostic methods, vaccines, specific therapy for associated diseases, improving the system of epidemiological surveillance of EBV infection, as well as further detailing the taxonomy and virus classification. The purpose of this review is to summarize and analyze the literature data on the genetic diversity of EBV for the prospective development of the methodology of molecular research in clinical practice and epidemiological surveillance of EBV-associated diseases. The work was carried out based on an analysis of publications in the PubMed, Web of Science, Scopus, eLibrary databases. Special attention was focused on the studies in Russia. It has been shown that approaches based on the analysis of nucleotide and amino acid variability of individual EBV genes or their regions have been used for several decades. However, there is no single, unified system that takes into account the entire genetic diversity of EBV, and the strengths and weaknesses of both earlier and modern classifications. Most publications are devoted to the study of the LMP-1 oncogene. With the development of whole genome sequencing technologies, the search for genovariants and subtypes of EBV has resumed. It is demonstrated that despite the dynamic development of this area, the conclusions of researchers are still based on a relatively small number of genomes sequenced with variable quality, analyzed using different bioinformatic strategies, with an unequal sample in terms of geographical origin. Moreover, some nosological forms of EBV-associated diseases, geographical areas and ethnic groups remain uncharacterized. The development and optimization of methodological approaches based on whole genome sequencing and sequencing of a specific set of genes will contribute to the expansion of existing ideas about the genetic diversity of EBV throughout the world, its relationship with diseases and, possibly, the clinical features of their course, and the improvement of epidemiological surveillance of EBV infection. 

In this review, methods for isothermal amplification of nucleic acids are considered and analyzed, in particular, loop isothermal amplification of DNA and RNA (LAMP/RT-LAMP), helicase-dependent amplification (HDA) and recombinase polymerase amplification (RPA). The advantages and disadvantages of each of the techniques are described. The possibility of their application in the molecular diagnostics of infectious diseases is evaluated. A brief review of the literature on the use of LAMP, HDA, RPA in the diagnostics of viral, bacterial infections and diseases of protozoal etiology was conducted. It has been shown that the LAMP method has a number of advantages over other diagnostic methods: high efficiency, specificity, simplicity, turnaround time and minimum requirements for instrument equipment. As a result, it is concluded that loop isothermal amplification is a promising method for detecting the DNA/RNA of various pathogens. The data on the introduction of the LAMP method in the diagnostics of particularly dangerous bacterial and viral infections, including for the detection of RNA of a new coronavirus infection (SARS-CoV-2) in clinical samples, are presented.

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