[Association of polymorphic variants of hemostatic system genes with the course of COVID-19].

INTRODUCTION:   COVID-19 is characterized by a varied clinical course. The aim of the work was to identify associations of SNPs of hemostatic system genes with COVID-19. MATERIALS AND METHODS: DNA was isolated from patients (n=117) and healthy participants (n=104). All infected patients were divided into 3 groups, depending on disease severity assessment, which was appreciated by NEWS2. Another group consisted of participants, who had asymptomatic infection in the past. Determination of SNPs of the genes FGB (-455 G/A), FII (20210 G/A), FV (1691 G/A), FVII (10976 G/A), FXIIIA1 (103 G/T), ITGA2 (807 C/T), ITGB3 (1565 T/C), SERPINE1 (-675 5G/4G) were performed by PCR using the "Genetics of Hemostasis" kit ("DNA-Technology", Russia). RESULTS: In analyzed SNPs, no significant differences were detected between the group of infected patients and healthy participants. But significant association was revealed in gene SERPINE1 (-675 5G/4G), when patient groups, differing in the disease severity, were analyzed relative to the group of participants with asymptomatic infection (p=0.0381; p=0 .0066; p=0.0009). It was found, that as COVID-19 severity scores increased, the proportion of 5G allele of gene SERPINE1 decreased, and the proportion of the 4G allele increased (p=0.005; p=0.009; p=0.0005). Similar processes were observed for genotypes 5G/5G and 4G/4G. DISCUSSION: The gene SERPINE1 (-675 5G/4G) is associated with the severity of COVID-19. CONCLUSION: For the first time, it was discovered that 5G/5G genotype of gene SERPINE1 (-675 5G/4G) can be a marker of a milder course of COVID-19, and the 4G/4G genotype as a more severe one.

[Peculiarities of the influenza and ARVI viruses circulation during epidemic season 2019-2020 in some regions of Russia].

INTRODUCTION: The surveillance of influenza viruses in ARVI structure and study of their properties in epidemic season 2019-2020 in Russian Federation are actual for investigations due to tasks of Global Influenza Strategy initiated by WHO in 2019. MATERIAL AND METHODS: The data of epidemiological surveillance on influenza- and ARVI-associated morbidity and hospitalization in different age groups of population were analyzed; virological, genetic and statistical methods were used. RESULTS: Preschool children were involved in epidemic the most. Meanwhile, the highest rate of hospitalization was observed in patients of 18-40 years old. Influenza A(H1N1)pdm09 virus dominated in etiology of ARVI in hospitalized patients and pneumonia. The role of respiratory viruses in severe cases of pneumonia and bronchoalveolar syndrome in children was shown. The differences in spectrum of circulating viruses caused ARVI in different regions of Russia were found. Influenza A(H1N1)pdm09 and B/Victoria-like viruses were the main etiological agents that caused of epidemic; its activity among all ARVI was 7.3 and 8.0%, respectively. The differences in antigenic properties of influenza A(H3N2) and B epidemic strains compared to vaccine viruses were found. The populations of epidemic strains were presented by following dominant genetic groups: 6B1.A5/183P for A(H1N1)pdm09, 3С.2а1b+137F for A(H3N2) and V1A.3 line B/Victoria-like for B viruses. The good profile of epidemic strains susceptibility to anti-neuraminidase inhibitors has been saved. The most of the studied influenza strains had the receptor specificity characteristic of human influenza viruses. CONCLUSIONS: Obtained results identified the peculiarities of viruses caused the influenza and ARVI in epidemic season 2019-2020 in different regions of Russia. These results suggested the important role of influenza A(H1N1) pdm09 in severe cases and pneumonia in adults 18-40 years old. The continuing drift in influenza viruses was found, which, apparently, could not but affect the efficacy of vaccine prophylaxis and was also considered in the recommendations of WHO experts on the composition of influenza vaccines for the countries of the Northern Hemisphere in the 2020-2021 season.

[Clinico-laboratory characteristics of viral hepatitis C with various HCV genotypes]. / Kliniko-laboratornaia kharakteristika virusnogo gepatita C pri razlichnykh genotipakh HCV.

Clinical and biochemical features of the acute phase of icteric hepatitis C in various HCV genotypes have been studied. The HCV genotypes determine the duration of incubation period and some clinical signs in the preicteric and icteric periods of acute hepatitis C. The biochemical picture and formation of chronic hepatitis virtually did not depend on the virus genotype.

[Effect of hepatitis G virus on the course of acute hepatitis B and C]. / Vliianie virusa gepatita G na techenie ostrogo gepatita B i C.

Examinations of 204 patients with acute viral hepatitis revealed HGV RNA in 65 (32%) cases. Clinical and laboratory data in HBV or HCV monoinfection virtually did not differ from these in co-infection with HBV + HGV and HCV + HGV.

[Role of delta infection in fulminant course of viral hepatitis]. / Rol' del'ta-infektsii pri ful'minantnom techenii virusnogo gepatita.

Sera from 35 fulminant hepatitis patients admitted to the hospital at the USSR AMS Research Institute of Virology in 1985-1989 were studied for specific markers of NB and delta infection. Delta-infection as etiological factor of the disease proved in 26 patients (74.3%). Acute hepatitis of mixed etiology (HBV and HDV) occurred in 17, acute hepatitis delta in 9 patients carrying chronically HBsAg. Acute hepatitis B was verified in the rest 9 patients. Clinical, biochemical and serological aspects typical for the variety of etiological variants of hepatitis running a fulminant course are considered.

[Lymphocyte subpopulations in patients with viral hepatitis B and delta-infections]. / Subpopuliatsii limfotsitov u bol'nykh virusnym gepatitom B i del'ta-infektsiei.

Changes in subpopulations of T3, T4, T8, HNK-1, Ia-positive, B-IgM and B-IgG producing lymphocytes were studied in patients with acute and chronic active virus hepatitis B and delta infection. A decrease of T4-helpers/inducers was demonstrated in all the groups under study and of T3-lymphocytes only in patients with delta-hepatitis turning into liver cirrhosis. The number of suppressors/cytotoxic T8 cells increased and T4/T8 ratio decreased in most patients. The number of HNK-1, Ia-positive, B-IgM and B-IgG lymphocytes increased in many subjects examined. Most marked quantitative changes in lymphocyte subpopulations were observed in patients with severe forms of delta-hepatitis and with liver cirrhosis. Changes in lymphocyte subpopulations in patients with viral hepatitis B and delta-infection are explained by reconstruction of the immune system in response to infection, affection of lymphocytes with viruses and emergence of antilymphocyte antibodies.

Monomeric (7S) and polymeric (19S) IgM anti-delta in acute and chronic delta infections.

The chromatographic profiles of IgM anti-delta in 45 acute and 24 chronic delta patients were analyzed by fast protein liquid chromatography (FPLC). Predominance of 19S IgM anti-delta was observed in the sera of 100 percent of coinfected and 62% of superinfected patients. In contrast, 7S IgM anti-delta was predominant in 83% of patients with chronic hepatitis delta. The study of the chromatographic profiles of IgM anti-delta in the development of the disease showed an association between the process of chronic delta-infection and the failure of 7S IgM anti-delta monomers to form 19S pentamers. The results showed that the test for 7S and 19S IgM anti-delta could be useful for differential diagnosis of acute and chronic hepatitis delta infection and for determining the prognosis of acute delta infection.

[The immune status in variants of the course and outcome of acute delta virus infection]. / Immunnyi status pri razlichnykh variantakh techeniia i iskhodov ostroi del'ta-virusnoi infektsii.

The immune status was investigated in 32 patients with acute hepatitis of mixed etiology and in 39 HBsAg carriers, superinfected with delta virus. The relationship of changes in the immune status with a course and outcomes of acute delta virus infection was revealed. These changes returned to normal on patients with a cyclic course of disease, persisted in patients with a lingering process, and progressed in the development of subacute liver dystrophy. The most noticeable shifts (a decrease in all indices of the immune system) were revealed in patients with a fulminant course of disease.