Detection of antibodies to the hepatitis E virus in domestic reindeer (Rangifer tarandus) in the Republic of Sakha (Yakutia).

INTRODUCTION: Although domestic pigs and wild boars are the main reservoir of zoonotic hepatitis E virus (HEV) genotypes in temperate countries, the presence of antibodies to HEV (anti-HEV) in the indigenous population of circumpolar territories, i.e. outside the habitat of wild and domestic pigs, indicates the presence of an alternative reservoir of the virus. Reindeer (Rangifer tarandus) may be a potential reservoir for HEV in the polar regions. The purpose of the study was to determine the prevalence of anti-HEV among domestic reindeer in the Republic of Sakha (Yakutia). MATERIALS AND METHODS: Sera from 497 domestic reindeer from the Oymyakon (n = 425) and Ust-Yansky districts (n = 72) of the Republic of Sakha (Yakutia) were tested for anti-HEV. A commercial ELISA kit DS-ELISA-ANTI-HEV-G (Diagnostic Systems-Stolitsa LLC, Russia) was used for detection of anti-HEV IgG, but a rabbit polyclonal antibody against deer IgG labeled with horseradish peroxidase (KPL, USA) at a dilution of 1 : 100 in phosphate-buffered saline were used instead of the human specific conjugate from the kit. RESULTS: The average detection rate of anti-HEV in reindeer sera was 15.5% (95% CI: 12.6-19.0%). The detection rate of anti-HEV significantly increased with age, from 3.5% (95% CI: 1.1-9.0%) in calves aged 3-6 months to 25.0% (95% CI: 1.6 -36.5%) in deer aged 2-4 years (p < 0.0001). From this age group, anti-HEV detection rates reached a plateau, not differing significantly between older age groups (p > 0.05). The average anti-HEV detection rate among reindeer 2 years of age and older was 19.0% (95% CI: 15.3-23.4%). There were no statistically significant differences in the frequency of anti-HEV detection between female and male reindeer, both among adult animals and among calves. CONCLUSION: The observed anti-HEV detection rates among domestic reindeer in the Republic of Sakha (Yakutia) indicate that infection caused by HEV or an antigenically similar virus is common in these animals. The dynamics of antibody accumulation in the reindeer population indicates that infection apparently occurs during the first two years of life.

[Assessment of external risk factors of hepatocellular cancer development and markers of genetic predisposition to its development in the ethnic group of yakut - men].

AIM: To establish the main external and genetically determined risk factors for the development of hepatocellular cancer in the ethnic group of male Yakuts living in the Republic of Sakha (Yakutia) [RS (Y)] in the epidemiologically unfavorable conditions of the incidence of viral hepatitis. MATERIALS AND METHODS: A total of 97 male Yakuts were examined, including 44 people diagnosed with hepatocellular cancer and 53 people diagnosed with chronic viral hepatitis. HCC risk factors were identified by analyzing medical records and questioning patients. In the experimental and control groups, genetic studies of single nucleotide polymorphisms of genes mapped on the X-chromosome and involved in the activation of antiviral immunity along the TLR7 signaling pathway were performed. RESULTS AND DISCUSSION: In 100% of patients with hepatocellular cancer, infection with hepatitis B, C, D viruses or co - infection with these agents was detected. Every fourth patient with HCC in the RS (Y) was infected with hepatitis D. The course of hepatocellular cancer associated with HDV was characterized by rapid progression of liver cirrhosis, development of portal hypertension, bleeding from varicose veins of the stomach and esophagus (36.4%) and edematous ascitic syndrome (63.6%). In addition to viral agents, additional risk factors for liver cancer were identified, such as alcohol abuse, overweight, diabetes mellitus, and smoking. Among the studied variation sites of genes localized on the X-chromosome and encoding the reaction of innate antiviral immunity, no genetic marker was found with a sufficient degree of confidence determining the likelihood of hepatocellular cancer developing. CONCLUSIONS: The high incidence of hepatocellular carcinoma of the male population in the RS (Y) is due to the widespread prevalence of parenteral viral hepatitis, especially viral hepatitis D. Due to the introduction of mass vaccination of the population against hepatitis B in the Russian Federation in the foreseeable future in the RS (Y) we should see a decrease in the proportion of hepatocellular cancer associated with hepatitis B and D viruses, and therefore the focus should be on the treatment and prevention of hepatitis C virus and non - infectious risk factors.

[FREQUENCY OF OCCURRENCE OF POLYMORPHIC VARIANTS OF IL28B GENE AND GENOTYPES OF HEPATITIS C VIRUS IN POPULATION OF YAKUTIA: CLINICAL OUTCOMES].

AIM: Study clinical outcomes in patients with chronic hepatitis C depending on genotype of hepatitis C virus (HCV) and IL28B gene polymorphism. MATERIALS AND METHODS: 592 indi- viduals Were examined, 75 ofthosehad HCVRNAgenotypes determined by PCR. Genotyping of single nucleotide polymorphisms (SNP) - rs12979860 (C/T) and rs8099917 (T/G) in IL28B gene was carried out by real-time PCR. RESULTS: HCV RNA was detected in 72 examined residents of Yakutia. HCV lb genotype was determined in 74.2% of cases, 3a - in 11.4%, la and 2 - 5.7% each. Frequency of polymorph variant rs12979860 CC was 72.2%, CT - 27.8%, rs8099917 TT - 61.1%, TG - 23.2%. CONCLUSION: Combination of HCV lb with polymorphic variants of IL28B'gene rs12979860 CC and rs8099917 CT showed a less aggressive course of the disease. On the other hand, HCV infection of individuals with geno- type 3a and polymorphism rs12979860 CC or rs809917 TT of IL28B gene showed a more severe clinical presentation. The presence ofpolyorirphvariants rs8099917 T/G and rs12979860 C/T showed more severe clinical outcomes of HCV infection (viral load up to 19035212 copies, cirrhosis with ascite, hepatocarcinoma).

[COMPARATIVE CHARACTERISTICS OF IMMUNE STATUS OF PATIENTS WITH CHRONIC FORMS OF VIRAL HEPATITIS B, C, D AND HEALTHY INDIVIDUALS].

AIM: Evaluate immune status in patients with chronic hepatitis (CH) depending on type of causative agent and severity of the infectious process. MATERIALS AND METHODS: 232 residents of Yakutia including 127 patients with various forms of chronic hepatitis and 105 healthy individuals were examined. Relative levels of mature T-lymphocytes (CD3⁺), T-helpers (CD4⁺), T-suppressors (CD8⁺), B-lymphocytes (CD72⁺) and naturalkillers (CD16⁺) were studied by flow cytometry, as well as concentration of sera immune globulins of classes A, M and G by ELISA. RESULTS: In patients with chronic hepatitis of various forms, a decrease of expression of differentiating antigens - CD3⁺, CD4⁺, CD72⁺ on the surface of lymphocytes and concentration of sera immune globulins was established. In CHD patients in phase of monoreplication high activity of the infectious process is accompanied by a shift of immune regulatory index to the increase of activity of cytotoxic cells with simultaneous development of deficiency of mature functionally active T-lymphocytes. In the -group of patients with hepatitis D virus with liver cirrhosis normal concentration of sera immune globulins is retained against the decrease of the number of T-helpers and B-lymphocytes. CONCLUSION: In patients with various forms of viral hepatitis acquired immune deficiency can emerge, which is often accompanied by enhancement of NK-cell activity. The noted reduction of the number of mature functionally active T-cells, as well as main classes of sera antibodies could be con- nected with immune system load during a chronic infectious process.

[Hardware and software for X-ray therapy planning].

Hardware, circuitry, and software suggested in this work make it possible to use the SLS-9 X-ray simulator for classical and computer tomographic imaging. The suggested hardware and software can be used as a basis for designing special-purpose tomographic systems.

[Viral hepatitis in different population groups of Republic of Sakha (Iakutia)]. / Shirota rasprostraneniia virusnykh gepatitov sredi razlichnykh grupp naseleniia na territorii respubliki Sakha (Iakutia).

A survey for the presence of markers of viral hepatitis B, delta, C and E among different groups of the population of the arctic and agricultural zones of the Republic of Sakha (Yakutia), as well as in Yakutsk, was carried out. The survey revealed that viral hepatitides with the parenteral mechanism of the transmission of infective agents were widely spread among the population. In the arctic zone HBsAg was detected in persons aged 20 years and older in 10.8-17.1% of cases. On the average, in the arctic zone antibodies to virus delta were detected in 2.4% of cases. In different regions of the agricultural zone the detection rate of HBsAg was also high (10.4-23.8%). In the Namsk and Vilyui regions delta infection was registered among adolescents (15-19 years of age) in 8.7 and 22.4% of cases respectively. In the Mountainous region anti-delta antibodies were detected among persons aged 20 years and older in 31% of cases. The survey showed the presence of considerable differences in the detection rate of the markers of hepatitis B, depending on the ethnic origin of the examined patients. Similar tendencies were found to exist with respect to delta infection.

[Evaluation of morbidity and etiological structure of acute and chronic viral hepatitis in the Sakha Republic (Yakutiia)]. / Otsenka zabolevaemosti i étiologicheskoi struktury ostrykh i khronicheskikh virusnykh gepatitov na territorii Respubliki Sakha (Iakutiia).

The morbidity of viral hepatitis was epidemiologically analyzed and the etiological structure of severe and chronic viral hepatitis was studied in the Republic of Sakha (Yakutia). Acute viral hepatitis B, whose portion is 43.5%, was found to be of the key significance within the structure of acute viral hepatitis (AVH). Acute viral hepatitis C (with 4.7% in the AVH structure) is by far more rare. The latter is close to the value registered in other Russia's regions. Apart from the prevalence of viral hepatitis B (32.4%) an exceptionally high share of chronic hepatitis delta (24.5%) was established for the etiological structure of chronic viral hepatitis, which is a specificity of the discussed region. The epidemic situation in the Republic of Sakha (Yakutia) was stated to be linked with the mentioned extra dangerous diseases, which requires appropriate emergency measures with the prevention vaccination program against hepatitis B being a priority.