Publications by authors named "Oleg Ogarkov"

In this study, we tested the skeletal human remains from the 18th - early 19th century Orthodox cemeteries in Irkutsk, Eastern Siberia, for tuberculosis-associated morphological alterations and Mycobacterium tuberculosis DNA. The morphologically studied bone collection included 591 individuals of mainly Caucasian origin. The molecular methods (IS6110-PCR and spoligotyping) suggested that at least four individuals (out of 15 TB-suspected, DNA-tested) were positive for the presence of M.

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This study aimed to determine phenotypic and genotypic drug resistance patterns of strains from children with tuberculosis (TB) in China and Russia, two high-burden countries for multi/extensively-drug resistant (MDR/XDR) TB. Whole-genome sequencing data of isolates from China ( = 137) and Russia ( = 60) were analyzed for phylogenetic markers and drug-resistance mutations, followed by comparison with phenotypic susceptibility data. The Beijing genotype was detected in 126 Chinese and 50 Russian isolates.

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Article Synopsis
  • The study focuses on the Mycobacterium tuberculosis Beijing 14717-15-cluster, which is a multidrug-resistant and hypervirulent strain found mainly in the Far Eastern region of Russia.
  • Researchers collected and analyzed M. tuberculosis DNA from worldwide locations between 1996 and 2020, developing a PCR assay to identify specific mutations related to this deadly strain.
  • Phylogenomic analysis confirmed the strain's prevalence in Asian Russia and highlighted unique mutations that could enhance its pathogenicity, suggesting the need for further research on these mutations' biological effects.
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Background: Rifampin-resistant and/or multidrug-resistant tuberculosis (RR/MDR-TB) treatment requires multiple drugs, and outcomes remain suboptimal. Some drugs are associated with improved outcome. It is unknown whether particular pharmacokinetic-pharmacodynamic relationships predict outcome.

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Objectives: We developed and tested a mobile health-based programme to enhance integration of HIV and tuberculosis (TB) care and to promote a patient-centred approach in a region of high coinfection burden. Phases of programme development included planning, stakeholder interviews and platform re-build, testing and iteration.

Setting: In Irkutsk, Siberia, HIV/TB coinfection prevalence is high relative to the rest of the Russian Federation.

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Eastern Siberia (Russia) and Mongolia are borderline regions in Asia with a high incidence of tuberculosis (TB). In this study, we investigated the transborder transmission of Mycobacterium tuberculosis with a focus on endemic and epidemic clones and drug resistance. M.

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The SARS-CoV-2 pandemic is a big challenge for humanity. The COVID-19 severity differs significantly from patient to patient, and it is important to study the factors protecting from severe forms of the disease. Respiratory microbiota may influence the patient's susceptibility to infection and disease severity due to its ability to modulate the immune system response of the host organism.

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Ancient sublineage of the Mycobacterium tuberculosis Beijing genotype is endemic and prevalent in East Asia and rare in other world regions. While these strains are mainly drug susceptible, we recently identified a novel clonal group Beijing 1071-32 within this sublineage emerging in Siberia, Russia and present in other Russian regions. This cluster included only multi/extensive drug resistant (MDR/XDR) isolates.

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strains of the early ancient sublineage of the Beijing genotype are mostly drug susceptible and mainly circulate in East Asia. We have recently discovered two clusters of this sublineage emerging in the Asian part of Russia (VNTR-defined 1071-32 and 14717-15 types) and, to our surprise, both were strongly MDR/XDR-associated. Here, we evaluated their pathogenic features.

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In Irkutsk, Siberia, there is a high prevalence of HIV and tuberculosis (TB) coinfection. Mobile health (mHealth) strategies have shown promise for increasing linkage to and engagement in care for people living with HIV (PLWH) in other contexts. We evaluated outcomes for a cohort of PLWH, TB, and substance use in Irkutsk after participation in a multi-feature mHealth intervention called MOCT.

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Background: Levofloxacin is a preferred drug for multidrug-resistant (MDR)-tuberculosis (TB) with bactericidal activity that correlates with the pharmacokinetic exposures of serum peak concentration (C) and total area under the concentration time curve (AUC). Pharmacokinetic exposures can be measured to personalize dosing to reach targets, but this practice requires venepuncture, chromatographic or mass spectrometry equipment, and technical expertise. We sought to demonstrate the accuracy of using urine colorimetry as a more feasible estimation of levofloxacin exposure.

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Article Synopsis
  • The Mycobacterium tuberculosis Beijing genotype is an important strain associated with drug resistance, divided into ancient and modern groups.
  • A study using next generation sequencing analyzed 184 genomes from various countries to understand the genetic factors behind drug resistance, particularly focusing on Russian isolates.
  • Findings revealed that Russian strains exhibited a significant level of drug resistance, with unique mutation signatures contributing to their pre-extensively drug-resistant (pre-XDR) and extensively drug-resistant (XDR) profiles, tracing back to origins in the early 1970s.
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Increasing rates of HIV/AIDS in Eastern Europe and Central Asia contrast global trends, but the scope of HIV/AIDS research originating from Russian Federation and countries of the former Soviet Union has not been quantified. We searched six major scientific databases in Russian and English languages with medical subject heading terms "HIV" or "AIDS" and "Russia" or "Soviet Union" from 1991 to 2016. Each abstract indexed was reviewed and tagged for 25 HIV/AIDS research themes, location of research focus and first author.

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The existence of "transrenal" DNA (tr-DNA), i.e. cell-free DNA that has distributed through the renal barrier to the urine, was first shown from a pathogen in 2000 (Botezatu et al.

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Background: d-cycloserine is used to treat multidrug-resistant tuberculosis. Its efficacy, contribution in combination therapy, and best clinical dose are unclear, also data on the d-cycloserine minimum inhibitory concentration (MIC) distributions is scant.

Methods: We performed a systematic search to identify pharmacokinetic and pharmacodynamic studies performed with d-cycloserine.

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Background: Ural genetic family is a part of the Euro-American lineage of Mycobacterium tuberculosis and is endemic in Northern Eurasia (former Soviet Union [FSU]). These strains were long described as drug susceptible and of low virulence, but recent studies reported an increasing circulation of the multidrug-resistant (MDR) and extensively drug-resistant (XDR) Ural strains. Here, we analyzed all publicly available whole genome sequence data of Ural genotype isolates, in order to elucidate their phylogenomic diversity with a special focus on MDR and potentially epidemic clones.

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Amplicon-based Next Generation Sequencing (NGS) is an emerging method for Mycobacterium tuberculosis drug susceptibility testing (DST) but has not been well described. We examined 158 clinical multidrug-resistant M. tuberculosis isolates via NGS of 11 resistance-associated gene regions covering 3519 nucleotides.

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We studied the significance of particular eis mutations on Mycobacterium tuberculosis drug resistance using a specialized transduction strategy. Recombinant strains harboring eis promoter mutations C14T, C12T, and G10A exhibited kanamycin resistance with MICs of 40, 10, and 20 μg/ml, respectively, while recombinant strains harboring C14G and C15G mutations were kanamycin susceptible (MIC, 2.5 to 5 μg/ml).

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Currently, Mycobacterium tuberculosis isolates of Latin-American Mediterranean (LAM) family may be detected far beyond the geographic areas that coined its name 15years ago. Here, we established the framework phylogeny of this geographically intriguing and pathobiologically important mycobacterial lineage and hypothesized how human demographics and migration influenced its phylogeography. Phylogenetic analysis of LAM isolates from all continents based on 24 variable number of tandem repeats (VNTR) loci and other markers identified three global sublineages with certain geographic affinities and defined by large deletions RD115, RD174, and by spoligotype SIT33.

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Unlabelled: Genotypic methods for drug susceptibility testing of Mycobacterium tuberculosis are desirable to speed the diagnosis and proper therapy of tuberculosis (TB). However, the numbers of genes and polymorphisms implicated in resistance have proliferated, challenging diagnostic design. We developed a microfluidic TaqMan array card (TAC) that utilizes both sequence-specific probes and high-resolution melt analysis (HRM), providing two layers of detection of mutations.

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Of 235 Mycobacterium tuberculosis isolates from patients who had not received tuberculosis treatment in the Irkutsk oblast and the Sakha Republic (Yakutia), eastern Siberia, 61 (26%) were multidrug resistant. A novel strain, S 256, clustered among these isolates and carried eis-related kanamycin resistance, indicating a need for locally informed diagnosis and treatment strategies.

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An interaction of different human alleles and endemic bacterial strains may be clinically manifested as different outcome of the disease in different hosts infected with the same genotype. The primary objective of this study was to investigate this issue in the model of Mycobacterium tuberculosis and human DC-SIGN encoding CD209 promoter SNP (rs4804803) in Russian Siberian population. We sought to find a possible combination of M.

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