Proton beam therapy in repeat irradiation of recurrent head and neck tumors: analysis of short-term results

Introduction. Recurrence of head and neck tumors occurs in 50 % of cases and usually has locoregional character. Due to the characteristics of dose distribution, proton beam therapy is a promising treatment option for patients with recurrences of tumors in this location who previously underwent radiation therapy.

Aim. To evaluate the effectiveness and tolerability of repeat irradiation using active scanning proton beam therapy in patients with recurrent head and neck tumors who previously underwent radiation therapy.

Materials and methods. Between November of 2015 and December of 2020, 40 patients with locoregional recurrence of head and neck tumors underwent treatment using active scanning proton beam therapy at the A. F . Tsyb Medical Radiological Research Center – branch of the National Medical Research Radiological Center. Median cumulative dose of primary irradiation was 64.5 Gy. Median time between primary and repeat irradiation was 35.7 months, mean irradiated volume of the repeat course was 94.5 cm3. Proton beam therapy was performed using standard mode (2 isoGy) and accelerated hypofractionation (2.4 isoGy / 3 isoGy) with mean equivalent cumulative dose of 56.4 Gy (α / β = 10). Radiation toxicity was evaluated using the Radiation Therapy Oncology Group European (RTOG) / Organization for Research and Treatment of Cancer (EORTC) scale.

Results. Treatment response was achieved in 34 (85 %) patients: in 17 (42.5 %) patients, stable disease was observed; in 10 (25 %) patients, partial response was observed; and in 7 (17.5 %) patients, complete response was observed. In 6 (15 %) cases, disease progression was diagnosed at first follow-up examination. One- and two-year locoregional control, progression-free survival and overall survival were 58.4 / 19.8; 44.5 / 19.8 and 82.3 / 38.8 % respectively with median follow-up duration of 14.2 months. Median survival was 19.5 months. Grade III and above early radiation toxicity was observed in 3 (7.5 %) patients. In total, 6 (15 %) cases of grade III complications and 2 (5 %) episodes of carotid artery rupture leading to death were observed. Overall frequency of complications of grade III and higher was 20 %.

Conclusion. Repeat irradiation using proton beam therapy can be considered an effective and safe treatment method for patients with recurrent head and neck tumors. Dosimetric and radiobiological benefits of proton beams allow to achieve balance between high doses and radiation exposure in previously irradiated tissues.

Modified quantitative approach for assessing peripheral blood TREC and KREC levels in immunodeficient patients

Introduction. The immune status is a multifaceted parameter quantitatively and qualitatively analyzing functional activity immune system state in immune organs as well as some non-specific mechanisms of antimicrobial protection. Peripheral blood level of T-receptor excision rings (TREC) and B-cell excision rings (KREC), respectively, can serve as surrogate markers of T- and B-cell maturation. Currently, the diagnostic kits available on the market have two significant disadvantages: i) the kits are aimed at diagnosing immunodeficiency conditions only in newborns and children, while keeping adult patients uncovered; ii) essentially, use solely single reference normalization gene for data normalization resulting in increased variability and decreased sensitivity of the assay data. The aim: to develop a highly sensitive method for laboratory assessment of the state of immunity in immunodeficient patients by using real-time PCR for assessing TREC and KREC level in children and adults. Materials and methods. There were used whole blood and dry blood spot samples obtained from newborns and adults, apparently healthy individuals as well as patients with verified PID and HIV-infection. A total of 2577 samples were examined. Commercial kits were used as comparison methods. Results. Multiplex PCR was carried out, analyzing the number of target molecules TREC and KREC, as well as fragments of the HPRT and RPP30 normalization genes analyzed with the developed series of plasmid calibrators. The established analytical range of TREC/KREC DNA measurements comprised 103 to 109 copies/mL. The accuracy of measurements on a tablet-type instrument (CFX) was 95.84%, on a rotary-type instrument (Rotor-Gene 3000) 95.11%, which corresponds to the standard indicator. The equivalence between the data obtained after assessing whole blood samples and dry blood drops was shown. The data analysis allowed to find out 100%-diagnostic specificity and sensitivity of the method proposed. Conclusion. The method developed by us allows to diagnose decline in T- and/or B-cell immunity in children and adults and can be used to detect TREC and KREC molecules both in peripheral whole blood samples and dry blood spots using Guthrie cards. Moreover, the uniform values of reference norms can be used regardless of the type of analyzed clinical material. The study data evidence about potential for effective use of multiplex PCR diagnostics both for complex primary testing/screening of newborns and assessing state of immunity to identify adult patients with PID and as a part of the diagnostic monitoring of patients with secondary immunodeficiencies, e.g., HIV infection.

Method for hepatitis B virus DNA detecting in biological material at low viral load based on nested PCR with detection on three viral targets in real-time mode

A method has been developed for HBV DNA finding in biological material at low viral load based on nested PCR with real-time detection of three viral targets. When developing the method, blood plasma samples were used from 128 CHB patients living in the regions of the Russian Federation and countries of Central Asia and 173 hemodialysis center patients living in the North-West Federal District. Analytical sensitivity was tested using the stepwise dilution method. HBV was detected by nested PCR. According to the method developed by us, at the first stage, the HBV DNA is amplified using at the first stage oligonucleotides complementary to the greatest similarity regions of the various HBV isolates genomes flanking the entire virus genome. At the second stage, when using the amplification product of the first stage as a template, PCR was performed using three pairs of oligonucleotides and the corresponding oligonucleotide fluorescently labeled probes to three virus genome regions (Core gene, S gene and X gene), as well as one pair of primers and the corresponding probe complementary to a human HPRT gene region. The method sensitivity for DNA extraction from plasma with a 100 μl volume was 10 IU/ml. Obtaining a threshold Ct cycle for only one fluorophore may indicate the presence of HBV DNA in the sample at a load of less than 10 IU/ml, HBV detection in this case is possible with a repeated PCR study of the corresponding sample with HBV DNA extraction from an increased plasma volume (200-1000 μl). The developed method makes it possible to identify the disease in various HBV subgenotypes and can be used to diagnose CHB in the population and risk groups, including those with the HBsAg-negative form of the disease.

[Genetic diversity of the human immunodeficiency virus (HIV-1) in the Kaliningrad region]

INTRODUCTION

As is currently known, the epidemic process in the Kaliningrad Region was mainly associated with the spread of the recombinant form of HIV-1 (CRF03_AB); however, regular HIV importations from other countries and continents has created favorable conditions for emergence and spread of various recombinant forms of the virus.The most complete information on the diversity of recombinant forms in the region is also necessary to understand the structure of drug resistance (DR). The aim of the study was to explore the HIV-1 genetic diversity in the Kaliningrad Region.

MATERIALS AND METHODS

We studied 162 blood plasma samples obtained from patients from the Kaliningrad Region, both with confirmed virological failure of antiretroviral therapy (ART) and with newly diagnosed HIV infection. For reverse transcription and amplification of HIV genome fragments, diagnostic «AmpliSense HIVResist-Seq».

RESULTS AND DISCUSSION

The various recombinants between subtypes A and B (74%) were predominant in study group: recombinant was between CRF03_AB and subtype A (33.95%) and CRF03_AB-like (13.58%) were the most common. Among the "pure" subtypes of the virus, subtype A6 (16.67%). The circulation of subtypes B (3.70%) and G (1.23%) was also noted.Ninety-six patients (59.26%) were identified with at least one mutation associated with antiretroviral (ARV) drug resistance.

CONCLUSION

The observed diversity of subtypes and recombinant forms of the virus implies that the new recombinants are actively emerging in the studied region, both between existing recombinant forms and "pure" subtypes, as well as between "pure" subtypes.

[Prevalence of viral hepatitis B markers among blood donors in the Republic of Guinea]

INTRODUCTION

The problem of transfusion safety in relation to parenteral viral hepatitis still remains relevant. Viral hepatitis B (HB) remains the most common viral infection transmitted through transfusion procedures. One of the natural phases of chronic hepatitis B (CHB) is occult hepatitis B infection (OBI), characterized by an undetectable HBsAg (regardless of the other serological markers content) in the presence of hepatitis B virus (HBV) DNA in the liver tissue and an extremely low, up to undetectable, level of viral load in the blood. In the Republic of Guinea, as in most countries on the continent, the prevention of HBV transmission through transfusion is still based on HBsAg serological testing of donors only. In this connection, OBI remains as a potential threat to blood transfusion safety. Detection of HBV DNA is a reliable preventive measure against transmission of the virus from donors with HBsAg-negative HBV infection, especially in highly endemic regions. In this regard, the study was conducted to substantiate recommendations for improving blood safety against the background of significant HBV prevalence in the Republic of Guinea.The aim of the work was the evaluation of serological and molecular markers of HBV infection in blood donors in the Republic of Guinea.

MATERIAL AND METHODS

We examined 250 blood samples obtained from donors living in Conakry, Republic of Guinea. Samples were tested for the presence of serological (surface antigen, HBsAg; antibodies (ABs) to surface (anti-HBs IgG) and core (anti-HBc IgG) antigens) and molecular (DNA) markers of HBV infection.

RESULTS AND DISCUSSION

The overall detection rate of hepatitis B markers was 83.2%; HBsAg was detected in 16.4% of all individuals. The high incidence of HBsAg in men (19.55%) compared to women (8.45%) was shown, the relative risk of HBV infection with the formation of HBsAg-positive chronic hepatitis B in males was also significantly higher. The prevalence of the HBV DNA in the study group was 30.4%, the OBI cases accounted for 15.6%. The prevalence of this form of the disease was shown in donors aged 30-49 years (24.78%), in the group of people younger than 30 years, the incidence was lower (8.73%), and at the age of over 50 years, OBI was not detected. Based on the phylogenetic analysis of 76 virus isolates, it was shown that genotype E prevails in the examined group (85.53%).Cases of pathogen DNA detection occurred in HBsAg-negative blood donors in the presence of anti-HBs IgG (n = 4), as well as in the simultaneous presence of ABs anti-HBs IgG and anti-HBc IgG (n = 7). The viral load exceeded 200 IU/ml in OBI samples. Escape mutations were detected by sequencing in each OBI sample, contributing to the virus escaping from diagnostic based on screening for HBsAg.

CONCLUSION

Assessment of the prevalence viral hepatitis B markers in blood donors, determination of genotypes and clinically significant mutations of virus variants are necessary to ensure safe medical manipulations, control and prevention of the spread of this infectious agent.

HIV-1 subtype diversity, phylogenetic analysis and study of drug resistance in strains circulating in the Ural Federal District

Introduction. Ural Federal District (UFD) has been one of the most HIV-affected areas in the Russian Federation during past 20 years. The total number of people living with HIV/AIDS (PLWH) and receiving antiretroviral therapy (ART) exceeds 100,000 (61.7% of all PLWH in the UFD), which creates opportunities for the wide spread of resistant HIV strains.Research aim was to determine the distribution of HIV-1 subtypes, evaluate the genetic heterogeneity of HIV-1 strains, and analyze the prevalence of HIV-1 drug resistance mutations (DRM) and the incidence of acquired resistance to antiretroviral drugs (ARVDs) in PLWH receiving ART in the UFD.Materials and methods. 223 patients receiving ART at stage III–IV of HIV infection living in the UFD were examined. To determine the subtypes and the DRM in the HIV-1 pol gene, molecular genetic studies were performed using the AmpliSense® HIV-Resist-Seq kit by Sanger sequencing on the Applied Biosystems 3500 Genetic Analyzer. The genetic heterogeneity was evaluated by calculating the identity of the genome region of the isolated strains in comparison with the genomes of foreign HIV strains, as well as using phylogenetic analysis.Results. In the studied group of patients, 5 subtypes of HIV-1 were identified: subtype A6 prevalence was 91.03%, that of subtype B was 2.69%, 3 recombinant subtypes (CRF03_A6B, CRF02_AG, CRF63_02A6) accounted for 6.28%. Among analyzed HIV-1 strains, 43.9% had a significant genetic similarity (identity of at least 97%) with the strains isolated from patients from neighboring countries (Belarus, Kazakhstan, Kyrgyzstan, Uzbekistan, Lithuania), 35.9% were similar to the strains isolated from patients from far-abroad countries (USA, China, South Korea, Australia, Sweden, Germany). A high heterogeneity of the circulating genetic variants of HIV-1 strains in the territory of the UFD region was established, which is an unfavorable factor for the diagnosis and treatment of HIV. The most common DRMs to both nucleoside reverse transcriptase inhibitors (NRTI) and non-nucleoside reverse transcriptase inhibitors (NNRTI) were detected in 81 specimens (36.3%). NRTI resistance-forming M184V DRM was more common than any other DRM with statistical significance (p = 0,0008) and was detected in 88 specimens (39.5%).Conclusion. In the subtype structure of HIV-1, the dominant subtype was subtype A6, the most common in the countries that were formerly part of the USSR. The heterogeneity of the HIV-1 strains circulating in the UFD suggests that HIV-1 infection continues to be introduced into the UFD from populations outside the Russian Federation. The findings confirm the high prevalence of DRMs (62.8%) and secondary drug resistance of HIV-1 (60.1%) among PLWH in the territory of the UFD. At the same time, high-level resistance was detected in 56.5% of patients, which requires increasing the coverage of HIV resistance testing, including the introduction of monitoring for primary resistance, in order to optimize first-line ART regimens. 

Algorithm for laboratory diagnostics of parvoviral infection in risk groups

Parvovirus infection (PVI) is widespread, characterized by airborne, bloodborne and vertical transmission routes. Parvovirus B19 (PVB19) exhibits tropism to erythropoietic cells. According to the increased likelihood principle of PVB19 infection and the severity of the consequences, immunocompromised individuals, especially those with hematological manifestations of diseases, are in increased risk group. Based on the own research results and analysis of the published data, we have proposed specific algorithms for PVI laboratory testing in individual risk groups, taking into account the peculiarities of the development and infection manifestation in each group: in HIV-infected patients, in oncohematological patients with to whom allogeneic hematopoietic stem cell transplantation (allo-HSCT) have been prescribed (blood and bone marrow recipients), as well as in patients with chronic anemia of parasitic etiology. For each group, the main clinical or laboratory marker, treatment procedure, or patient physiological parameters have been determined, based on which it was recommended to test for PVI. For HIV-infected patients, the main criterion for PVI testing is persistent anemia. For oncohematological patients, the basis for PVI testing is allo-HSCT procedure, which is planned or performed for this particular patient. For malaria patients, the patient's age was considered as major criterion, since in malaria and PVI coinfected young children can lead to a fatal outcome. The proposed PVI diagnostics algorithms usein risk groups can help to predict the severe course of underlying disease associated with PVB19 infection, and timely correct the therapy used.

Peptidoglycan of Bacterial Cell Wall Affects Competitive Properties of Microorganisms

We studied the effect of bacterial wall peptidoglycan of 7 bacterial species on the competitive properties of human-associated microorganisms. Addition of peptidoglycan to the culture medium did not change the growth characteristics of the test cultures; however, an increase in the antagonism and hydrophobicity of Bifidobacterium sp. and Enterococcus sp. was observed, while the effect on enterobacteria was predominantly indifferent or inhibitory. The effect did not depend much on the source of peptidoglycan and was equally manifested on both indigenous and probiotic strains. The observed new property of peptidoglycan indicates its participation in the formation and functioning of microbiota. The obtained data on the regulation of the properties of microorganisms provide new possibilities for the correction and maintenance of host homeostasis through host-associated microbiota.

Method for detecting hepatitis B virus in blood plasma at low viral load using real-time PCR

A method for detecting HBV DNA in peripheral blood at low viral load using real-time PCR was developed and its significance in identifying HBsAg-negative viral hepatitis B was evaluated. When developing the method, blood plasma samples and liver tissue biopsy material were used from 128 patients living in St. Petersburg, in various regions of the Russian Federation, as well as in the Central Asia countries. We also used blood plasma samples from 96 pregnant women and 37 hemodialysis center patients living in Northwestern Federal District, 199 foreign citizens undergoing medical examination to obtain work permits at the Directorate for Migration in the Northwestern Federal District, 397 conditionally healthy people living in the Socialist Republic of Vietnam. HBV was detected by nested PCR. Analytical sensitivity was tested using the stepwise dilution method. According to the method developed by us, at the first stage, the HBV DNA is amplified using at the first stage oligonucleotides flanking the genome region 2932-3182 ... 1-1846 nt., and at the second stage two oligonucleotides pairs to the genome virus regions (gene S and gene X) and corresponding oligonucleotide fluorescently labeled probes complementary to the amplified fragments regions carrying fluorophores at the 5'-end, and non-fluorescent quenchers at the 3'-end. The channel corresponding to the FAM fluorophore detects the HBV DNA S-region amplification product, and the channel corresponding to the ROX fluorophore detects the HBV DNA X-region amplification product. The method sensitivity for DNA extraction from plasma with a 100 μl volume was 10 IU/ml. Obtaining a threshold cycle Ct for only one FAM or ROX fluorophore may indicate the HBV DNA presence in a sample at a load of less than 10 IU / ml, HBV detection in this case is possible with a repeated PCR study of the corresponding sample with HBV DNA extraction from an increased plasma volume (200-1000 μl). The developed method makes it possible to identify various HBV genovariants, both characteristic and rare in the Russian Federation, circulating in other world regions. The method can be used to detect HBV in risk groups, in the population, as well as in screening blood donors in order to ensure the blood transfusions safety.

Optimization of the algorithm diagnosis chronic hepatitis B markers in patients with newly diagnosed HIV infection

The possibility of modifying the algorithms for chronic viral hepatitis B laboratory diagnosis in individuals with newly diagnosed HIV infection is analyzed. Plasma samples were used from 196 patients residing in the Northwestern Federal District. Serological HBV markers were found in 79.6% of cases. However, HBsAg was detected in 5.6% of patients. Anti-HBcore IgG antibodies are found in 62.24% of cases, anti-HBe IgG antibodies in 27.55%, anti-HBs IgG antibodies in 52.55% of cases. Using a commercial kit with a 100 IU / ml sensitivity, HBV DNA was detected in 4.6% of patients, that is, 81.8% of HBsAg-positive individuals. Using the method developed by us, HBV DNA was found in 18.36% of HIV-infected individuals, including 12.75% of cases was HBsAg-negative (latent) disease form. In the examined group, HBV of genotype D prevailed (91.7%), genotype A was detected in 8.3% of cases. The distribution of subgenotypes is presented in the following ratios: D2 - 55.6%, D1 - 22.2%, D3 - 13.9%, A2 - 8.3%. Mutations were detected in the reverse transcriptase (RT) region in 91.6% of patients, in the SHB region in 83.3%, in the Core and Precore regions in 72.2% and in 27.7% of patients, respectively. Three HBV isolates (8.3%) were identified with drug resistance mutations to lamivudine, entericavir, telbivudine and tenofovir, which are amino acid substitutions in the HBV polymerase gene at positions L180M, T184A, M204V. Vaccine escape mutations were detected in 61.1% of patients. In all samples with drug resistance mutations, escape-mutants were simultaneously present. When analyzing the basal nucleus promoter, Precore and Core regions, 22.2% of patients with the double mutation A1762T / G1764A, 25% with the mutation G1896A were identified. In one person, all three substitutions were found. In the Core region, 77.7% of patients showed mutations in one of the hot spots (codons 87, 97, 112, and 130 substitution), which can play a role in immunomodulation in CHB. Analysis of the HBV genetic structure, mutations detection early in the virus in patients with HBV can help predict the clinical course and disease progression, and ART complications. To reduce the HIV HBV co-infection burden and to appointer anti-HBV therapy, it is necessary to introduce detection the occult HBV to modify the algorithm for CHB laboratory diagnosis.

Serological diagnosis and prevalence of HIV-1 infection in Russian metropolitan areas

BACKGROUND

HIV infection is a major health problem in Russia. We aimed to assess HIV prevalence in different population groups and to compare the characteristics of 4th generation immunoassays from Abbott, Bio-Rad, Vector-Best, Diagnostic Systems, and Medical Biological Unit.

METHODS

The study included 4452 individuals from the general population (GP), 391 subjects at high risk of HIV infection (HR) and 699 with potentially interfering conditions. HIV positivity was confirmed by immunoblot and by HIV RNA, seroconversion and virus diversity panels were also used. HIV avidity was employed to assess recent infections.

RESULTS

The prevalence in GP was 0.40%, higher in males (0.62%) and in people aged < 40 years (0.58%). Patients attending dermo-venereal centers and drug users had a high prevalence (34.1 and 58.8%). Recent infections were diagnosed in 20% of GP and in 4.2% of HR. Assay sensitivity was 100% except for one false negative (99,54%, MBU). Specificity was 99.58-99.89% overall, but as low as 93.26% on HR (Vector-Best). Small differences on early seroconversion were recorded. Only the Abbott assay detected all samples on the viral diversity panel.

CONCLUSION

HIV infection rate in the high-risk groups suggests that awareness and screening campaigns should be enhanced. Fourth generation assays are adequate but performance differences must be considered.

[Identification and molecular-genetic characteristics of the hepatitis B virus among HIV-infected patients in Arkhangelsk.]

AIM

To estimate the prevalence and characterize the hepatitis B virus among HIV-infected patients with virological failure of antiretroviral therapy in Arkhangelsk.

MATERIAL AND METHODS

HBV markers determinations (HBsAg, anti-HBs IgG, antiHBcor IgG, DNA HBV) were performed in isolates from blood plasma samples 64 HIV-infected patients with virological failure of antiretroviral therapy (viral load >50 IU / ml after 6 months of antiretroviral therapy or an increase in viral load after primary suppression of viral replication). For the detection of the hepatitis B virus, nucleic acids were isolated using the commercial kit «AmplePrime Ribo-prep». The virus presence analysis was performing by the polymerase chain reaction (PCR) method with hybridization-fluorescence detection in "real time" using the commercial set of «AmpliSens^® HBV-FL». In the future, we used the method developed by the Saint-Petersburg Pasteur Institute, which allows detecting HBV in biological material with a low viral load.

RESULTS

HBsAg-negative (occult) HBV was detect in 28 (43.8%) HIVinfected patients. Only HBV genotype D was detected, and the HBV subgenotype D1 prevailed (39.3%) compared with the HBV subgenotype D2 (32.1%) and D3 (28.6%). Serological markers in 42.8% of patients with HBV DNA were founding. Two HBV isolates with drug resistance mutations in the polymerase gene, leaded to amino acid substitutions (L180M, M204V) associated with the resistance development to lamivudine, entecavir, telbivudine and tenofovir were identifying.

CONCLUSION

The occult (HBsAg-negative) HBV high prevalence among HIV-infected patients suggests the need to use molecular-biological diagnostic methods to identify HBV, as well as to analyze the HBV drug resistance mutation before starting antiretroviral therapy for HIV.

[The prevalence clinically significant virus mutations among patients with chronic viral hepatitis B.]

The prevalence of clinically significant virus mutations in patients with chronic viral hepatitis B from the Kyrgyz Republic was analyzed. Blood plasma samples of 64 patients with verified chronic viral hepatitis B obtained from Kyrgyzstan indigenous people were used in the work. Asymmetric PCR was carried out with extended oligonucleotides and the first reaction amplification product was further used in a new PCR with one of the nested pairs overlapping primers that flanked the entire HBV genome together, followed by sequencing. Based on the phylogenetic analysis of 64 HBV isolates obtained from patients from the Kyrgyz Republic, it was shown that only the genotype D virus was present in the examined group, the HBV subgenotype D1 (68.75%) prevailed compared with the HBV subgenotype D2 (18.75%) and subgenotype D3 (12.5%). For all subgenotypes, several independent infection sources are obvious, subclusters that include isolates from Kyrgyzstan, Kazakhstan and Uzbekistan are distinguished, as well as subclusters that include isolates only from Kyrgyzstan, which are less similar to isolates previously deposited in the international database, which probably indicates an independent HBV homologous evolution in the region. Clinically significant mutations were identified in 26.5% of patients. Including 12.5% with escape mutations that prevent the virus detection and / or allow the virus to replicate despite the vaccine (122K, 128V, 133I, 134N). Another 12.5% of the isolates are characterized by mutations that are independently associated with the liver cirrhosis and hepatocellular carcinoma development, including 21, 24, 27 nucleotides deletions in the Pre-S2 region and the S11F mutation in the PreCore region. In one case, unusual 236S and 250P mutations were found in the positions described as drug resistance sites of the P region associated with the resistance development to adefovir, tenofovir, and entecavir. The hepatitis B virus genetic structure analysis, early virus mutations detection in patients with chronic hepatitis B virus can help to choose the right vaccination strategy, antiviral and immunosuppressive therapy, as well as predict the clinical course and disease progression.

Plasma Cytokines Profile in Patients with Parkinson's Disease Associated with Mutations in GBA Gene

Plasma cytokine concentration in patients with Parkinson's disease and mutation in GBA gene, in patients with sporadic Parkinson's disease, and in healthy volunteers were measured by ELISA and multiplex analysis. In patients with Parkinson's disease and mutation in GBA gene, elevated plasma concentrations of IL-1β and TNFα were revealed by ELISA in comparison with both controls and patients with sporadic form of Parkinson's disease. Multiplex analysis revealed enhanced secretion of IL-1β, IL-2, IFNγ and reduced plasma levels of monocyte chemoattractant protein-1 (MCP-1) in patients with Parkinson's disease and mutation in GBA gene (in comparison with other groups) and increased plasma levels of IL-13 (only in comparison with the healthy volunteers). Our results support the hypothesis that the concentrations of inflammatory mediators are increased in patients with Parkinson's disease and mutation in GBA gene.

[Hepatitis B virus identification in a blood plasma at a low viral load.]

To analyze the method for detecting HBV DNA in peripheral blood at low viral load and evaluate its significance in identifying HBsAg-negative viral hepatitis B. In this work, samples of blood and liver tissue biopsy material were used from 128 patients living in the Russian Federation and the Republic of Uzbekistan without CHB and with CHB confirmed detection of circle covalently closed HBV DNA in hepatocytes. Plasma viral load was measured using the «AmpliSens® HBV-Monitor-FL» kit. HBV at low viral load was detected by nested PCR. Analytical sensitivity was checked by step dilution. According to our method, at the first stage, an asymmetric PCR is carried out using extended oligonucleotide primers with different melting points, complementary to the hepatitis B different genotypes genomes greatest similarity region. To increase the sensitivity, a second PCR is performed using the first reaction amplification product and internal primers. The sensitivity of the method for DNA extraction from 100 μl of plasma was 5 IU / ml, specificity 100%. Since, in spite of the HBV genotypes characteristic geographical distribution, the detection of "alien" genovariants for certain territories is becoming more frequent, we tested the method in geographically remote but active international relations with the Russian Federation regions with a high frequency of hepatotropic viruses. The developed method for detecting HBV DNA in blood plasma at low viral load based on PCR technology allows the various HBV gene variants identification and genotyping, both characteristic and rare in the Russian Federation, circulating in other world regions. The method can be used to detect HBV in risk groups, in a population, as well as when screening blood donors in order to ensure the blood transfusions safety.

[The quantitative determination method of covalently closed circular DNA HBV in puncture biopsy specimens of the liver.]

To analyze the method HBV covalent-closed circular DNA quantitative determination in liver puncture biopsies and evaluate its significance in identifying HBsAg-negative viral hepatitis B. In this work, samples of liver tissue biopsy material were used from 128 patients living in St. Petersburg, in various regions of the Russian Federation, as well as in the Republic of Uzbekistan. For quantitative analysis of HBV covalently closed circular DNA in a biopsy material a method was developed based on real-time PCR using TaqMan probes for the target fragment and for the endogenous reference gene, based on the detecting ccc HBV DNA method of Pollicino T. et al. When quantifying ccc DNA HBV in liver tissue of 18 moderately HBV activity with HBV DNA PCR positive results patients and 16 inactive HBsAg carriers, the ccc DNA HBV content was significantly different between groups (p<0.034) and in terms 1 copy of the β-globin gene among moderate activity HBV patients amounted to 1.71±1.32 copies/cell, and for inactive HBsAg carriers 0.15±0.14 copies/cell. In the group of patients with severe liver fibrosis and cirrhosis, the amount of ccc DNA HBV in liver tissue in patients with HBV averaged 2.5±0.4 copies/cell, in patients with HBV + D on average 0.7±0.25 copies/cell, in patients with HCV + HBV co-infection 0.45±0.07 copies/cell, in patients with a preliminary diagnosis of chronic hepatitis C hepatitis, on average 0.12±0.04 copies/cell, in patients with cryptogenic hepatitis 0.2± 0.05 copies/cell. A significant difference was shown between the group of patients with chronic hepatitis B with marked fibrosis and cirrhosis of the liver with other patients groups, except for the group of 18 moderate activity chronic hepatitis B patients. The values of Student's t-test when compared with other groups were respectively: for patients with a HCV preliminary diagnosis t=5,92 p<0,05 f = 19, patients with cryptogenic hepatitis t=5,71 p<0,05 f = 18, with «inactive HBsAg carriage» t=5,55 p<0,05 f = 29, with HCV + HBV co-infection t=5,05 p<0,05 f = 15 and HBV + D co-infection t=3,82 p<0,05 f = 17. The covalently closed circular DNA HBV quantitative assessment method in liver puncture biopsies allows identifying HBsAgnegative chronic viral hepatitis B forms and also reflects the virus replication activity, which, in turn, makes it possible to assume further disease progression and evaluate the antiviral therapy effectiveness.

Variety of the hepatitis B virus genovariants in the military

Aim. To estimate the distribution of genotypes and subgenotypes of the hepatitis B virus among military personnel with chronic viral hepatitis B. Materials and methods. The work used samples of blood plasma and biopsy material obtained from 90 active or retired military personnel with chronic viral hepatitis B with various degrees of fibrosis undergoing treatment in St. Petersburg. Primary detection of HBV was carried out by isolating nucleic acids (NK) from the blood plasma using the «AmplePrime Ribo-prep» commercial kit (FBIS CRIE, Moscow). Specific primers were used for the amplification and sequencing reaction. Overlapping primer pairs were used, jointly flanking 1475 base pairs (bp) fragment, including the recommended for HBV genotyping the 1169 bp Pre-S1/Pre-S2/S. Results. Among 90 samples from patients with chronic viral hepatitis B from different regions of the Russian Federation, HBV subgenotypes are represented in the following ratios: D2 = 45.6% (n=41), D1 = 32.2% (n=29), D3 = 13.3% (n=12), A2 = 6.7% (n=6), D4 and A1 by 1.1%, respectively. The distribution of HBV subgenotypes from the North Caucasian federal district (D1 – 63.6%, D2, D3, D4, A2 – by 9.1%) was significantly different from the distribution among patients from the Central and North-Western federal districts (D1-20, 9%, D2 – 58%, D3 – 16.3%, A2 – 4.8%) (χ2=11,9приp=0,0076, df=3). Uncharacteristic for the Russian Federation subgenotypes D4 and A1, representing single imported cases. The tendency to shift the distribution of genovariants due to imports of the corresponding HBV subgenotypes from other countries, including the Central Asian countries, is discussed. Conclusion. A systematic study of the HBV isolates phylogeny provides new information about the HBV subgenotypes distribution among certain population groups, including military personnel.

The NNbar and multihadron production at the threshold at VEPP2000

A study of hadron production at the nucleon-antinucleon threshold has been performed with the CMD-3 detector at the VEPP-2000 e+e− collider. A very fast rise with an about 1 MeV width has been observed in the e+e−→ pp̅ cross section. A sharp drop in the e+ e−→ 3(π+π−) cross section has been con?rmed and found to have a width of less than 2 MeV, in agreement with the observed fast rise of the e+e−→ pp̅ cross section. For the ?rst time a similar sharp drop is demonstrated in the e+e−→ K+ K−π+π− cross section. The behavior of the e+e−→ 3(π+ π−), K+ K−π+π− cross sections cannot be explained by an interference of any resonance amplitude with continuum, therefore this phenomenon cannot be due to a narrow near-threshold resonance. No such structure has been observed in the e+e−→ 2(π+π−) cross section.

Recent results from CMD-3

Regular data taking with the CMD-3 at the electron-positron collider VEPP-2000 is under way since 2010. The collected data sample corresponds to about 200 inverse picobarns of integrated luminosity per detector in the energy range from 0.32 up to 2 GeV, with a goal to collect about 1 fb−1 during next five years. Some of the recent results from the CMD-3 detector are discussed.

THE PREVALENCE OF OCCULT HEPATITIS B AMONG HBSAG-NEGATIVE PERSONS WITH HIV IN VELIKY NOVGOROD

Aim: to estimate the prevalence of the occult hepatitis B virus among HIV-infected patients with the virological ineffectiveness of antiretroviral therapy in Veliky Novgorod. Materials and methods. Blood plasma samples from 76 HBsAg-negative HIVinfected patients with virological inefficiency of antiretroviral therapy from Veliky Novgorod were used in the work. For the detection of the hepatitis B virus, nucleic acids were isolated using the commercial kit AmplePrime Ribo-prep. For amplification and sequencing, overlapping pairs of specific primers were used, jointly flanking a 1475 base pair fragment including the 1169 base pair Pre-S1/Pre-S2/S region recommended for genotyping the hepatitis B virus. Results. Among 76 samples of hepatitis B virus DNA, 44 samples were found, which was 57,89%. None of the patients had HBsAg, and 6 patients (13,63%) had HBcor IgG and HBe IgG antibodies. On the basis of phylogenetic analysis, it was shown that only genotype D, which is the most common genotype of the hepatitis B virus in the Russian Federation, was detected in the examined group. The subgenotype D2 (47,72%) prevailed in comparison with the subgenotype D1 (34,09%) and the subgenotype D3 (18,18%). The distribution possible ways of the subgenotype D1 hepatitis B virus, which is uncharacteristic for the region, are discussed. Only one isolate of hepatitis B virus with mutations of drug resistance to nucleotide / nucleoside analogue therapy has been identified — amino acid substitution in the polymerase gene of the virus (L180M, M204V) associated with the development of resistance to lamivudine, entecavir, telbivudine and tenofovir. Conclusion. The high prevalence of occult hepatitis B among HIVinfected patients indicates a lack current tests for the diagnosis of chronic HBV infections. The identification of occult hepatitis B in HIV-infected individuals seems appropriate for timely treatment of patients and requires the use more sensitive methods.

Study of the process e+e−→ K+K−π0 in the center-of-mass energy range 1.2–2 GeV with the CMD-3 detector

The process e+ e−→ K+ K−π0 has been studied in the center-of-mass energy range from 1.2 to 2 GeV using a 80.6 pb−1 data sample collected with the CMD-3 detector at the electron-positron collider VEPP-2000. Preliminary results of the cross-section measurement are presented.

Study of the e+e−→ KS KLπ0 process up to 2 GeV with the CMD-3 detector at the VEPP-2000 collider

The cross section of the process e+ e−→ KS KL π0 has been studied with the CMD-3 detector at the VEPP-2000 electron-positron collider in the center-of-mass energy range from 1.1 to 2 GeV. Preliminary results on the total cross section of the process are presented.

An amplitude analysis of the process e+e-→ 4π in the center-of-mass energy range 900–2000 MeV with the CMD3 detector at the VEPP-2000 e+e- collider

A large data sample of e+e-→ 4π collected by the CMD-3 experiment at the VEPP-2000 e+ e− collider allowed for an amplitude analysis of the process e+e−→ 4π in the center-of-mass energy range 900–2000 MeV. Various intermediate components were distinguished and dominance of the ωπ0 and a1π amplitudes has been proved.

Study of the process e+e-→π+π-γ with the CMD-3 detector at the e+e- collider VEPP-2000

Existing Monte-Carlo generators with radiative corrections to the e+e-→π+π- process are usually developed under the assumption that pions can be treated as pointlike particles. We study the e+e-→π+π-γ process with final-state radiation and test this assumption using simulated events from the MCGPJ generator based on the scalar QED hypothesis. In order to increase a fraction of events with FSR, the analysis was performed in the energy region to the left from the ρ-meson peak (660÷785 MeV) that is based on the integrated luminosity of about 8.4 pb-1. The experimental data for the photon energy spectrum agree with the simulation results at 1% level.

Search for the process e+e−→D*(2007) with the CMD-3 detector

A search for the process e+e−→ D*0(2007) has been performed with the CMD-3 detector at the VEPP-2000 e+e−-collider. Two main decay modes of the D*0(2007) decay, D0π0 and D0γ, followed by D0 → K+π−π+π−are used in this analysis. With an integrated luminosity of 3.7 pb−1 collected at the center-of-mass energy Ec.m. =2006.62 MeV our preliminary upper limit is BD*0→e+ e− <1.6× 10−6 at 90%C.L.

Study of π+π−π+π− production with CMD-3 detector at the VEPP-2000 collider

The cross section of the process e+e−→ π+π−π+π− has been measured using an integrated luminosity of 17 pb−1 collected with the CMD-3 detector in the center-of-mass energy range 650-1000 MeV. High-precision measurements of various hadronic cross sections are of great interest in relation with the problem of the muon anomalous magnetic moment g-2. This measurement can be also used to test the relation between the cross section of e+e−→ π+ π−π+ π− and the spectral function for the τ−→ π−π0π0π0 decay predicted by the conservation of vector current (CVC).

Nanocrystalline SiC film thermistors for cryogenic applications

We developed a heat-sensitive material based on nanocrystalline SiC films obtained by direct deposition of carbon and silicon ions onto sapphire substrates. These SiC films can be used for resistance thermometers operating in the 2 K-300 K temperature range. Having high heat sensitivity, they are relatively low sensitive to the magnetic field. The designs of the sensors are presented together with a discussion of their thermometric characteristics and sensitivity to magnetic fields.

[THE IDENTIFICATION OF STENOTPHOMONAS MALTOPHILIA USING THE TECHNIQUES OF DIRECT SEQUENATION 16S P RNA AND MALDI-TOF MASS-SPECTROMETRY]

The in-hospital infections are one of the most serious problems of medicine, especially if patients have a background immunosuppression of various genesis conditioned by both disease itself and corresponding therapy. The detection of presence of infection and identification of agent and detection of its resistance are needed for choosing adequate therapy. At that, high heterogeneity of strains and multiple resistance of nosocomial infections to antibiotics and antimicrobial pharmaceuticals and standardization of antibacterial prevention and number of other causes becomes an obstacle for both determination of medicinal sensitivity of bacterium and for identification of pathogen itself in patient. One of the most complicated in antibacterial therapy pathogens causing pyo-septic diseases, are bacteria Stenotrophomonas spp., the only significant species out of them - Stenotrophomonas maltophilia has primary multiple antibiotic resistance. The significance of early identification of S.maltophilia is obvious. The application of MALDI-ToF mass-spectrometry requires shortage of of time of species identification of primary bacterial culture up to 1-2 hours including sampling preparation and analysis of obtained specters. The sequencing of 16S rRNA requires shortage of of total time od species identification of pathogen from clinical sample (blood) up to 1-12 hours, including sampling preparation ans comparison with successions presented in international data base. The given technique permits to exclude out of analysis prolonged period of obtaining a pure hemoculture of agent. The application of sequencing of 16S rRNA and MALDI-ToF mass-spectrometry as an alternative high-precision techniques shorten time of identification of bacteria, including detection of agent directly in blood of patient. Hence, occurs optimization of complex treatment and shortage of time of selection of adequate therapy that is especially important in case of oncological patients because sensitivity of cultural methods can be diminished due to preventive antibiotics' therapy.

[ZIKA FEVER: CLINICAL, EPIDEMIOLOGICAL, LABORATORY, AND DIAGNOSTIC ASPECTS]

The authors overview data on the prevalence of Zika fever with reference to biological properties of the causative agent, epidemiological process, pathogenesis, and clinical symptoms of the disease. Special attention is given to the identification of the virus in pregnant women, microcephaly in the babies born by Zika-infected women, algorithm of laboratory diagnostics, and measures needed to prevent and control mosquitoes that spread viruses.

[The possibilities for diagnostics of prescription of death coming based on the changes in the lumbar intervertebral disks (the comparison of the morphological, immunohistochemical and topographical findings)]

The objective of the present study was the comprehensive analysis of the postmortem changes in the lumbar intervertebral disks within different periods after death. A total of seven vertebromotor segments were distinguished in the lumbosacral region of the vertebral column based on the examination of 7 corpses. All these segments were divided into three groups in accordance with the prescription of death coming as follows: up to 12 hours (group 1), between 12 and 24 hours (group 2), and between 24 and 36 hours (group 3) after death. The models of the segments thus obtained were subjected to the study by means of diffusion weighted MRI. The removed intervertebral disks were used for morphological and immunohistochemical investigations. The comparison of the diffusion coefficients (DI) revealed the significant difference between the intervertebral disks assigned to groups 1 and 2 (p<0.01). The number of the cells in the pulpal core, the vertebral end plate, and the fibrous ring in all the above groups of the intervertebral disks was significantly reduced (p<0.01). The analysis of the correlation dependence between cell density and diffusion coefficients has demonstrated the well apparent relationship between these characteristics of the intervertebral disks comprising groups 1 and 2. It is concluded that diffusion weighted MRI in the combination with the calculation of diffusion coefficients for the intervertebral disks provides a tool for diagnostics of prescription of death coming as confirmed by the results of the morphometric studies and immunohistochemical analysis.

Superconductivity in highly disordered NbN nanowires

The topic of superconductivity in strongly disordered materials has attracted significant attention. These materials appear to be rather promising for fabrication of various nanoscale devices such as bolometers and transition edge sensors of electromagnetic radiation. The vividly debated subject of intrinsic spatial inhomogeneity responsible for the non-Bardeen-Cooper-Schrieffer relation between the superconducting gap and the pairing potential is crucial both for understanding the fundamental issues of superconductivity in highly disordered superconductors, and for the operation of corresponding nanoelectronic devices. Here we report an experimental study of the electron transport properties of narrow NbN nanowires with effective cross sections of the order of the debated inhomogeneity scales. The temperature dependence of the critical current follows the textbook Ginzburg-Landau prediction for the quasi-one-dimensional superconducting channel I _c ∼ (1-T/T _c)^3/2. We find that conventional models based on the the phase slip mechanism provide reasonable fits for the shape of R(T) transitions. Better agreement with R(T) data can be achieved assuming the existence of short 'weak links' with slightly reduced local critical temperature T _c. Hence, one may conclude that an 'exotic' intrinsic electronic inhomogeneity either does not exist in our structures, or, if it does exist, it does not affect their resistive state properties, or does not provide any specific impact distinguishable from conventional weak links.

HBV COVALENTLY CLOSED CIRCULAR DNA AS A MARKER OF PREVALENCE OF OCCULT HEPATITIS В IN PATIENTS WITH HBV, HDV AND HCV INFECTION IN UZBEKISTAN

Aim. Evaluate significance of covalently closed circular DNA of hepatitis В virus as a marker for detection of occult viral hepatitis В in Uzbekistan population with hepatitis of various genesis. Materials and methods. Blood plasma and liver biopsy from 39 patients with different severity levels of liver fibrosis and cirrhosis served as study material. HBV covalently closed circular DNA detection was carried out according to Pollicino T. et al. (2004). Results. Covalently closed circular DNA of hepatitis В virus was detected in 82% of samples, including in 54.5% of patients with chronic viral hepatitis C (CVHC) and in 100% of patients with hepatitis of unknown etiology. Quantitative evaluation of content of covalently closed circular DNA of hepatitis В virus in liver tissue in patients with CVHB has shown an average of 2.5 copies of HBV genome as ccc DNA per cell, in patients with CVHB + D an average of 0.7 copies/cell, in patients with co-infection by HCV and HBV - 0.5 copies/cell, in patients with CVHC an average of 0.12 copies/cell, and in patients with cryptogenic hepatitis - 0.2 copies/cell. Conclusion. Detection of HBV DNA is a complex problem for effective laboratory diagnostics of hepatitis. Detection of H BV ccc DNA as a marker of occult hepatitis В in patients with CVHC and patients with hepatitis of unclear etiology is an important factor for diagnostics, selection of adequate therapy, prognosis of disease outcome and prevention of development of severe liver diseases.

MOLECULAR-BIOLOGICAL MARKERS OF HEPATITIS В IN PATIENTS WITH LIVER FIBROSIS/CIRRHOSIS IN UZBEKISTAN

Aim. Evaluate prevalence of genetic variants of hepatitis В viruses in population of various regions of Uzbekistan with hepatitis of various genesis and different severity levels of liver fibrosis and cirrhosis. Materials and methods. Blood plasma and liver biopsy from 39 patients with different severity levels of liver fibrosis and cirrhosis served as study material. Genotyping based on direct sequencing of Pre-Sl/Pre-S2/S HBV DNA region was applied. Results. Hepatitis В virus was detected in 32 samples ofthe 39 provided, frequency of occurrence - 82%, respectively. Phylogenetic analysis has shown, that only genotype D was detected among the examined patients, hepatitis В virus subtype D1 predominated (84.38%) compared with D2 (3.12%) and D3 (12.5%) subtypes. Conclusion. Large-scale sequencing of HBV in Central Asia will allow to evaluate routes of transmission and time of evolutionary separation of virus isolates. Understanding the epidemiology of the infectious process is important for development of programs for prophylaxis and therapy of the infection.

Dose-Response of Micronuclei in Binucleated and Mononucleated Lymphocytes from Cytochalasin Culture (Irradiation in vivo and in vitro)

The dose-responses of micronuclei (MN) in binucleated (BN) and mononucleated (MONO) lymphocytes cultivated with cytochalasin B (CBMN-assay) were studied. Irradiation of lymphocytes was performed in vitro (donor A) at the single dose of 1 and 2 Gy of (60)Co y-rays, or in vivo, during whole-body exposure of a cancer patient (donor B) to (60)Co γ-rays each day at a single dose of 0.115 Gy up to a total dose of 1.15 Gy. The linear dose-response for MN was determined in both BN and MONO lymphocytes of donor B. It means that when CBMN assay is applied, the MN in MONO cells represent those preexisted in vivo before each exposure. On the contrary, in lymphocytes of donor A irradiated in vitro an essential elevated MN yield with an - increased dose was observed only in BN lymphocytes. A slight dose dependent elevation of MN in MONO cells seems to be due to either their division before cytochalasin was introduced in the culture medium or their insensitivity to the CB block of cytokinesis.

[MOLECULAR-BIOLOGICAL MARKERS OF HEPATITIS B IN PATIENTS WITH LIVER FIBROSIS/CIRRHOSIS IN UZBEKISTAN]

AIM

Evaluate prevalence of genetic variants of hepatitis B, viruses in population of various regions of Uzbekistan with hepatitis of various genesis and different severity levels of liver fibrosis and cirrhosis.

MATERIALS AND METHODS

Blood plasma and liverbiopsy from 39 patients with different severity levels of liver fibrosis and cirrhosis served as study material. Genotyping based on direct sequencing of Pre-S1/Pre-S2/S HBV DNAregion was applied.

RESULTS

Hepatitis B virus was detected in 32 samples ofthe 39 provided, frequency of occurrence - 82%, respectively. Phylogenetic analysis has shown, that only genotype D was detected among the examined,patients, hepatitis B virus subtype D1 predominated (84.38%) compared with D2 (3.12%) and.D3 (12.5%) subtypes.

CONCLUSION

Large-scale sequencing of HBV in, Central Asia will allow to evaluate routes of transmission and time of evolutionary separation or virus isolates. Understanding the epidemiology of the infectious process is important for development of programs for prophylaxis and therapy of the infection.

[HBV COVALENTLY CLOSED CIRCULAR DNA AS A MARKER OF PREVALENCE OF OCCULT HEPATITIS B IN PATIENTS WITH HBV, HDVAND HCV INFECTION IN UZBEKISTAN]

AIM

Evaluate significance of covalently closed circular DNA of hepatitis B virus as a marker for detection of occult viral hepatitis B in Uzbekistan population with hepatitis of various genesis.

MATERIALS AND METHODS

Blood plasma and liver biopsy from 39 patients with different severity levels of liver fibrosis and cirrhosis served as study material. HBV covalently closed circular DNA detection was carried out according to Pollicino T et al. (2004).

RESULTS

Covalently closed circu- lar DNA of hepatitis B virus was detected in 82% of samples, including in 54.5% of patients with chronic viral hepatitis C (CVHC) and in 100% of patients with hepatitis of unknown etiology. Quantitative evaluation of content of covalently closed circular DNA of hepatitis B virus in liver tissue in patients with CVHB has shown an average of 2.5 copies of HBV genome as ccc DNA per cell, in patients with CVHB + D an average of 0.7 copies/cell, in patients with co-infection by HCV and HBV - 0.5 copies/cell, in patients with CVHC an average of 0.12 copies/cell, and in patients with cryptogenic hepatitis - 0.2 copies/cell.

CONCLUSION

Detection of HBV DNA is a complex problem for effective laboratory diagnostics of hepatitis. Detection of HBV ccc DNA as a marker of occult hepatitis B in patients with CVHC and patients with hepatitis of unclear etiol- ogy is an. important factor for diagnostics, selection of adequate therapy, prognosis of disease outcome and prevention of development of severe liver diseases.

Coherent Excited States in Superconductors due to a Microwave Field

We describe theoretically the depairing effect of a microwave field on diffusive s-wave superconductors. The ground state of the superconductor is altered qualitatively in analogy to the depairing due to a dc current. In contrast to dc depairing, the density of states acquires, for microwaves with frequency ω_{0}, steps at multiples of the photon energy Δ±nℏω_{0} and shows an exponential-like tail in the subgap regime. We show that this ac depairing explains the measured frequency shift of a superconducting resonator with microwave power at low temperatures.

[Zika virus infection: clinical and diagnostic aspects and organization of preventive measures]

The article presents modem data about Zika virus outbreak, the biological characteristics of the pathogen, vectors, the nature of the epidemic process, pathogenesis and diagnosis of infection. This infection has a high potential for epidemic spread because vectors are widely represented in the fauna of many climatic and geographic zones. It presents information on the main clinical manifestations of the disease. Particular attention is paid to the problem of congenital maiformations of the nervous system (microcephaly and others) detected in infants born to women infected with Zika virus. The basis of therapy in this disease constitute a pathogenic agent. The'package of, measures for the prevention of disease caused by Zika virus, including early identification and treatment of patients, as well as measures for the destruction of the virus vectors.

[TYPING OF LEPTOSPIRA SPP. STRAINS BASED ON 16S rRNA]

AIM

Comparative typing of Leptospira spp. strain collection based on analysis of 16S RNA fragment.

MATERIALS AND METHODS

2 pairs of primers were used for PCR, that jointly flank 1423b.p. sized fragment. Sequences of Leptospira spp. strain 16S rRNA, presented in the international database, were used for phylogenetic analysis.

RESULTS

A high similarity, including interspecies, of the 16S fragment in Leptospira spp. strains was shown independently of the source, serovar and serogroup. Heterogeneity of the primary matrix, spontaneous mutations of hotspots and erroneous nucleotide couplings, characteristic for 16S sequence of pathogenic Leptospira spp. strains, are discussed. Molecular-genetic characteristic of certain reference Leptospira spp. strains by 16S sequence is obtained.

CONCLUSION

Results of the studies give evidence on expedience of introduction into clinical practice of identification of Leptospira spp. by 16S sequence directly from the clinical material, that would allow to significantly reduce identification time, dismiss complex type-specific sera and other labor-intensive methods.

[Frequency of chromosomal aberrations in lymphocytes of peripheral blood in patients with solid tumors]

There was carried out a study to compare the frequency of spontaneous chromosomal aberrations (CA) in lymphocytes of peripheral blood between the group of cancer patients with different types of solid tumors and the group of healthy people of the same age. There was established a significant increase in the average frequency of CA in cancer patients. Analysis of the group of patients has revealed its heterogeneity: in the majority of patients the individual frequency of CA significantly exceeded the average frequency of CA in the control group, in some - did not differ from that. The first patients were described as the group with "generalized" genomic instability. Also this group differed by increased radiosensitivity of lymphocyte chromosomes during their irradiation in vivo.

Analysis of Populations of Memory T-Helper Cells Expressing CXCR3 and CCR6 Chemokine Receptors in Peripheral Blood of Patients with Chronic Viral Hepatitis C

Flow cytometry was employed to examine the content of major populations of memory T helper cells and expression of chemokine receptors CXCR3 and CCR6 on their surface in peripheral blood drawn from virtually healthy people and the patients with chronic viral hepatitis C. The following combination of monoclonal antibodies had been used: CD62LFITC/CD45RA-PE/CD3-ECD/CCR6-PC7/CXCR3-APC/CD4-APC-Cy7. In comparison with control group, the patients with chronic hepatitis C had a smaller number of populations of naïve CD4(+) T cells and central memory CD4(+) T cells but a greater number of terminally differentiated effector memory CD4(+) T cells and effector memory CD4(+) T cells. No differences were revealed between CD4(+) T cell populations of both groups in expression of CXCR3 and CCR6 receptors.

[PRODUCTION OF CERTAIN PRO- AND ANTI-INFLAMMATORY CYTOKINES DURING STIMULATION BY LIVE AND INACTIVATED LEPTOSPIRA PATHOGENS IN THE MODEL OF HUMAN WHOLE BLOOD]

AIM

Study of the ability of clinical isolates of leptospira to cause production of certain pro- and antiinflammatory cytokines in the model of human whole blood.

MATERIALS AND METHODS

Leptospira interrogans strain was taken for the experiment. Cytokine content was determined by a method based on xMAP technology using a standard panel, composed of 9 analytes: TNF-α, MCP-1, IL-8, IL-4, IL-6, IL-10, IL-IRa, IL- 12 (p70), IFN-γ.

RESULTS

An optimal concentration of L. interrogans was selected for stimulation of human whole blood--1 x 10(6) leptospirae/ml. For the first time in the model of human whole blood it was determined, that at early stages of incubation IFN-γ, IL-12(p70), IL-4 and IL-1Ra are more actively produced; at later stages (6 hour incubation)--IL-8 and TNF-α.

CONCLUSION

A differential pattern of cytokine production stimulation was shown in the model of human whole blood by live and inactivated leptospirae.

[THE ROLE OF CYTOKINES AND CHEMOKINES IN LABORATORY DIAGNOSTIC OF CHRONIC VIRAL HEPATITIS C]

The chronic viral hepatitis C is widely prevalent disease with prolonged persistence of virus and obliterated clinical picture. The present techniques of diagnostic of degree of fibrosis of liver and prognosis of course of disease have particular shortcomings. Hence, search of safe low invasive methods based on blood biomarkers is an actual task. The cytokines/chemokines (mediators of chronic inflammation) directly involved into immunopathogenesis of chronic viral hepatitis C can act in the capacity of biomarkers. The study was carried out to comprehensively analyze content of cytokines/chemokines in peripheral blood of patients with chronic viral hepatitis C at various stages of disease and infected by different genotypes of virus of hepatitis C. The concentration of cytokines/chemokines was identified in blood plasma of patients with chronic viral hepatitis C (n = 73) and conditionally healthy donors (n =3 7): IFNα, IFNγ, IFNλ/IL28α, TNFα, CCL2/MCP-1, CCL3/MIP-lα, CCL4/MIP-lβ, CCL5/RANTES, CCL8/MCP-2, CCL20/AIP-3α, CXCL9/MIG, CXCL10/P-10, CXCLII/ITAC. The multiplex analysis using technology xMAP was applied. The increasing of level of TNFα, CCL2/MCP-1, CCL4/ MIP-l, CCL8/ACP-2, CCL20/MIP-3α, CXCL9/MIG, CXCL10/IP-10, CXCL11/ITA C was established in blood plasma of patients with chronic viral hepatitis C as compared with control group. The levels of analyzed interferons IFNα, IFNγ, IFNλ/IL28α had no difference in studied groups. As far as chronic viral hepatitis C progresses and fibrosis of hepatic tissue develops the concentrations of TNFα, CCL2/MCP-1, CCL20/MIP-3α, CXCL9/MIG, CXCL10/IP-l0, CXCL11/ITAC increased significantly. The concentrations of chemokine CXCL11/IT4 C can be used as informative indicator for differentiating diagnostic of early stages of liver fibrosis. Depending on genotype of virus of hepatitis C, in patients with chronic viral hepatitis C change in content of CCL8/MCP-2 was established. Hence, detection in blood plasma of patients with chronic viral hepatitis C concentration of particular cytokines/chemokines using multiplex analysis technique permit analyzing additional information concerning degree of liver fibrosis, activity of process of damage of hepatic tissue under chronic viral hepatitis C that indicates indirectly on genotype of virus of hepatitis C.