Khamzat K. Murtazaliev, M. A. Makarova, Lidiya A. Kaftyreva, Elena V. Alieva, Aza V. Oshaeva, Marina K. Zhamborova
{"title":"Molecular markers of acute intestinal infections in HIV-infected patients in the Chechen Republic","authors":"Khamzat K. Murtazaliev, M. A. Makarova, Lidiya A. Kaftyreva, Elena V. Alieva, Aza V. Oshaeva, Marina K. Zhamborova","doi":"10.36233/0372-9311-437","DOIUrl":"https://doi.org/10.36233/0372-9311-437","url":null,"abstract":"Introduction. Diarrheal syndrome is the most characteristic symptom of HIV infection, which occurs in 70% of patients and is often fatal. The severity of diarrheal syndrome, irrespective of immune status, is usually determined by specific microorganisms colonising the gastrointestinal tract. \u0000The objective of this study is to assess the prevalence of classical pathogens of acute intestinal infections in diarrheal syndrome in HIV-infected residents of the Chechen Republic (Grozny). \u0000Materials and methods. Stool samples (n = 191) of HIV-infected patients with a history of diarrheal syndrome were studied by real-time PCR with two kits of reagents: \"AmpliSens OKI screen-FL\" for the detection of DNA/RNA of Shigella spp./EIEC, Salmonella spp., Campylobacter spp., Adenovirus, Rotavirus, Norovirus and Astrovirus; \"AmpliSens Escherichiosis-FL\" for the detection of diarrheagenic E. coli (DEC) DNA of five pathogroups: EPEC, EHEC, ETEC, EIEC, EAgEC. \u0000Results. Genetic markers of the acute intestinal infection pathogens were detected in 20.9% of the examined individuals. In patients aged 0–7 years and 18–24 years, DNA/RNA of the tested pathogens were not detected. DNA of bacterial pathogens accounted for 93.9%, RNA of viral pathogens — 6.1%. The etiological structure of bacterial infections was represented by a significant predominance of DEC (84.8%) compared to 10.9% of Campylobacter spp. and 4.4% of Salmonella spp. The structure of viral infections included 66.7% Rotavirus and 33.3% Norovirus. Genetic markers of Adenovirus and Astrovirus have not been identified. In 77.5% of HIV-infected patients, diarrheal syndrome was caused by one pathogen (mono-infection), but in nine examined patients (22.5%) it had a combined etiology. \u0000Conclusion. The etiology of acute intestinal infections in HIV-infected patients of the Chechen Republic includes bacterial and viral pathogens, in every fifth the cause of diarrheal disease was DEC. Due to diarrhea in HIV-infected people being a polyetiological disease, it is necessary to introduce a comprehensive, fast, reliable, and affordable method for identifying a wide range of pathogens that cause secondary infections.","PeriodicalId":508236,"journal":{"name":"Journal of microbiology, epidemiology and immunobiology","volume":"56 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139384956","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Aleksandr V. Lyashko, I. Rudneva, Dmitrii N. Shcherbinin, N. Lomakina, Anastasiya A. Treshchalina, Irina M. Kupriyanova, A. Gambaryan, E. B. Timofeeva, A. Shilov, G. Sadykova, Alexey G. Prilipov, B. I. Timofeev, Maxim M. Shmarov, E. L. Ryazanova, T.A. Timofeeva
{"title":"The adaptive potential of North American subtype H7N2 avian influenza viruses to mammals","authors":"Aleksandr V. Lyashko, I. Rudneva, Dmitrii N. Shcherbinin, N. Lomakina, Anastasiya A. Treshchalina, Irina M. Kupriyanova, A. Gambaryan, E. B. Timofeeva, A. Shilov, G. Sadykova, Alexey G. Prilipov, B. I. Timofeev, Maxim M. Shmarov, E. L. Ryazanova, T.A. Timofeeva","doi":"10.36233/0372-9311-395","DOIUrl":"https://doi.org/10.36233/0372-9311-395","url":null,"abstract":"Introduction. H7 subtype avian influenza viruses causing severe epizootics among birds are phylogenetically different in the Eastern and Western hemispheres. Numerous human infections caused by these viruses in the Eastern hemisphere indicate that H7 viruses can overcome the interspecies barrier and pose a potential threat of a new pandemic.The H7N2 viruses with deletion of amino acids 221–228 (H3 numbering) in hemagglutinin (HA) had been circulating among poultry in the Western Hemisphere during 1996–2006, and had once again been detected in 2016 in an animal shelter, where they caused cat diseases. \u0000The objective of this study is to elucidate the mechanism of adaptation to mammals of North American H7N2 influenza viruses with deletion in HA. \u0000Materials and methods. The A/chicken/New Jersey/294598-12/2004 (H7N2) virus was adapted to mice by the lung passages. Complete genomes of original and mouse-adapted viruses were analyzed. The receptor specificity and thermostability of viruses, HA activation pH and virulence for mice were determined. \u0000Results. The non-pathogenic H7N2 avian influenza virus became pathogenic after 10 passages in mice. Amino acid substitutions occurred in five viral proteins: one in PB2 (E627K), NA (K127N), NEP (E14Q), four in HA and six in NS1. Mutations in HA slightly changed receptor specificity but increased the pH of HA activation by 0.4 units. The NS1 protein undergone the greatest changes in the positions (N73T, S114G, K118R, G171A, F214L and G224R), where amino acid polymorphisms were observed in the original virus, but only minor amino acid variants have been preserved in the mouse adapted variant. \u0000Conclusion. The results show that H7N2 viruses have the potential to adapt to mammals. The increase in virulence is most likely due to the adaptive E627K mutation in PB2 and possibly in HA.","PeriodicalId":508236,"journal":{"name":"Journal of microbiology, epidemiology and immunobiology","volume":"58 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139384898","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
O. Voronina, Марина S. Kunda, N. Ryzhova, E. Aksenova, Z. Sadeeva, I. Novikova, Anna V. Lazareva, O. Karaseva, А. P. Fisenko, A. L. Gintsburg
{"title":"Genomic features of resistant Klebsiella pneumonia, isolated from the bloodstream and cerebrospinal fluid of pediatric hospital patients","authors":"O. Voronina, Марина S. Kunda, N. Ryzhova, E. Aksenova, Z. Sadeeva, I. Novikova, Anna V. Lazareva, O. Karaseva, А. P. Fisenko, A. L. Gintsburg","doi":"10.36233/0372-9311-430","DOIUrl":"https://doi.org/10.36233/0372-9311-430","url":null,"abstract":"Introduction. Carbapenemase-producing Klebsiella pneumoniae (CP-Kp), which are international high-risk clones, have become a problem of utmost importance. CP-Kps, adapting to the hospital environment, evolve into convergent pathotypes. Such variants combine traits of two genetic lineages: multidrug resistant (MDR) and hypervirulent. The pathotypes, along with MDR K. pneumoniae, pose an exceptional threat to young patients during systemic infection. \u0000The objective of this study is the detailed molecular genetic analysis of MDR isolates of K. pneumoniae detected during the monitoring of resistant Gram-negative bacteria at the National Medical Research Center for Children’s Health in 2014–2021. \u0000Materials and methods. Whole-genome sequencing with a subsequent bioinformatics analysis of eight MDR isolates from the bloodstream and cerebrospinal fluid. \u0000Results. MDR isolates belonged to 4 sublineages (SL): SL307, SL395, SL29 and SL1198. In the genomes of 6 pangrug-resistant (PDR) isolates, genes associated with resistance to all categories of antibiotics recommended for Enterobacteriaceae therapy were identified. Plasmids were present in all genomes. In 6 isolates, plasmids contained heavy metal ion resistance operons in addition to antibiotic resistance genes. Prophages within the plasmids were also involved in the transfer of resistance genes. The ST395 isolate from the cerebrospinal fluid belonged to the convergent pathotype in terms of resistance and virulence. Comparison of genomes within SLs revealed recombination events in the K- and O-locus regions and the Yersiniabactin operon. \u0000Conclusion. Thus, in a sample of resistant K. pneumoniae isolated from bloodstream and cerebrospinal fluid, 6 PDR isolates were detected, one of which belongs to the convergent pathotype ST395.","PeriodicalId":508236,"journal":{"name":"Journal of microbiology, epidemiology and immunobiology","volume":"31 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139386941","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
N. M. Afonina, Irina V. Mikheeva, M. Korabelnikova, Z. S. Rodionova, A. Snitsar, Sergey N. Perekhodov, Svetlana V. Smetanina, A. Tutelyan, Stanislav N. Kuzin, V. G. Akimkin
{"title":"Results of screening for antibodies to varicella-zoster virus in healthcare workers of a multidisciplinary hospital in Moscow","authors":"N. M. Afonina, Irina V. Mikheeva, M. Korabelnikova, Z. S. Rodionova, A. Snitsar, Sergey N. Perekhodov, Svetlana V. Smetanina, A. Tutelyan, Stanislav N. Kuzin, V. G. Akimkin","doi":"10.36233/0372-9311-427","DOIUrl":"https://doi.org/10.36233/0372-9311-427","url":null,"abstract":"Introduction. Given the unfavorable epidemic situation with chickenpox and shingles in Russia, there is a high risk of virus introduction and spread in healthcare settings, including among medical staff who are not immune to varicella zoster virus (VZV). \u0000The objective of this study is to assess the immunity of employees of a multidisciplinary hospital in Moscow to VZV. \u0000Materials and methods. A selective screening study was carried out. Venous blood serum samples were taken from 1546 hospital employees as material for detection of IgG antibodies to VZV antigens using a commercial solid-phase enzyme immunoassay (ELISA) test system \"Vecto VZV-IgG\". All employees were questioned to obtain information about their infectious and vaccine history in relation to VZV. \u0000Results and discussion. Screening for antibodies to VZV in the hospital workers revealed that 6.3% of those workers are not immune to VZV. The proportion of seronegative individuals was the highest (12.6 ± 2.4%) in the age group of 29 years and younger. VZV seronegative healthcare workers were found in various departments, but the presence of non-immune individuals among the staff of the obstetrics and gynecology departments (6.5%) is of epidemiologic concern. The results of the survey showed that documented data on infection and vaccination history cannot be used to assess the protection of healthcare workers against VZV infection. \u0000Conclusion. The results of serologic screening for antibodies to VZV made it possible to identify a significant number of susceptible employees of the multidisciplinary hospital. In order to prevent the formation of multiple epidemic foci of varicella in medical organizations, it is advisable to include anti-VZV testing of medical staff in the state prevention programs with subsequent vaccination of non-immune individuals.","PeriodicalId":508236,"journal":{"name":"Journal of microbiology, epidemiology and immunobiology","volume":"10 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139385295","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tat'yana Victorovna Tsareva, O. Yanushevich, V. Tsarev, M. Podporin, I. Balmasova
{"title":"BACTERIA GENUS FILIFACTOR IN PATIENTS WITH PERIODONTITIS AND DIABETES MELLITUS ACCORDING TO METAGENOMIC ANALYSIS OF THE PERIODONTAL MICROBIOME","authors":"Tat'yana Victorovna Tsareva, O. Yanushevich, V. Tsarev, M. Podporin, I. Balmasova","doi":"10.36233/0372-9311-428","DOIUrl":"https://doi.org/10.36233/0372-9311-428","url":null,"abstract":"Periodontal disease is a widespread pathology, and chronic periodontitis is the most severe form of its manifestation. In recent years, the problem of this polymicrobial disease has acquired particular importance due to the possibility of developing concomitant systemic effects. Quite often, chronic periodontitis is combined with type 2 diabetes mellitus. The etiopathogenetic mechanisms that determine this association include so-called periodontal pathogenic bacteria, with the recently discovered periodontal pathogen Filifactor alocis being the least studied. The purpose of the study is identification of bacteria of genus Filifactor in the periodontal microbiome in the association of chronic periodontitis and type 2 diabetes mellitus and clarification of the mechanisms of their possible influence on associated metabolic processes based on comparative metagenomic analysis. Materials and methods..A metagenomic study of periodontal pocket microbiome samples from 28 chronic periodontitis and diabetes mellitus type 2 association patients and 22 chronic periodontitis patients, as well as the periodontal sulcus microbiome from 19 clinically healthy individuals, was conducted. To determine the taxonomic composition of the microbiome, 16S sequencing of the ribosomal RNA gene was used, and metabolic pathways involving the microbiome were predicted using the shotgun method. The results obtained made it possible to establish that the most common microorganism in the association of chronic periodontitis and type 2 diabetes mellitus were Filifactor genus bacteria. The percentage of their registration correlated with low rates of metagenomic prediction of fatty acid biosynthesis and pyrimidine metabolism in lesions. Conclusion. The frequency of occurrence of Filifactor genus bacteria in patients with the association of chronic periodontitis and type 2 diabetes mellitus was associated with negative correlations with certain features of the putative metabolic pathways of the microbiome, which included fatty acid biosynthesis and pyrimidine metabolism.","PeriodicalId":508236,"journal":{"name":"Journal of microbiology, epidemiology and immunobiology","volume":"21 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139177138","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. M. Nagornykh, M. Tyumentseva, A. I. Tyumentsev, V. Akimkin
{"title":"Accumulated experience and future prospects of in vivo hepatitis B virus research","authors":"A. M. Nagornykh, M. Tyumentseva, A. I. Tyumentsev, V. Akimkin","doi":"10.36233/0372-9311-446","DOIUrl":"https://doi.org/10.36233/0372-9311-446","url":null,"abstract":"Nowadays, an estimated more than 300 million people live with hepatitis B virus (HBV) infection globally. One of the main goals of the World Health Organization (WHO) is to eliminate viral hepatitis by the year 2030. The study of the pathogenic and immunologic properties of HBV, as well as therapeutic substances and treatment regimens, is significantly complicated by the insufficient number of susceptible animal models and the lack of zoonotic reservoirs of the virus. In this regard, researching the properties of HBV and related hepadnaviruses provides invaluable material for understanding the biology of the pathogen and the developing methods of prevention and control of this chronic infectious disease, leading to severe hepatopathies such as cirrhosis and hepatocellular carcinoma. Furthermore, prolonged HBV viremia leads to depletion of the immune system, reducing resistance against pathogens of other infections, especially those with a chronic course and socially determined spread. The objective of this research is to evaluate existing animal models of HBV infection in the context of pathogenesis, immunologic and pathomorphological features. For the first time, the hypothesis of the possible use of certain models for the research of HBV-associated socially significant infections is considered from the angle of the development of pathomorphological features. To complete this review, we analyzed the information about the features of in vivo HBV infection models, published over the last 25 years in open sources (Web of Science, PubMed, Scopus, ScienceDirect, Springer). The main criteria for literature selection were the type of infecting agent, the observed immunologic features of the course of the infectious process and the availability of a description of the pathomorphological picture in model organisms.","PeriodicalId":508236,"journal":{"name":"Journal of microbiology, epidemiology and immunobiology","volume":"24 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139209906","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
E. N. Vetrova, Alyona I. Chernyshova, Tatiana N. Pritchina, O. Morozova
{"title":"Monitoring of respiratory viral infections in Moscow during 2011–2022","authors":"E. N. Vetrova, Alyona I. Chernyshova, Tatiana N. Pritchina, O. Morozova","doi":"10.36233/0372-9311-376","DOIUrl":"https://doi.org/10.36233/0372-9311-376","url":null,"abstract":"Introduction. Respiratory viruses (RV) circulate throughout the world and in all seasons of the year. Long-term monitoring of the distribution of respiratory pathogens is necessary to analyze the relevance of diagnostic systems to current viral isolates, to assess the risks of infection and the need for vaccine development and use, as well as to investigate the interdependence of RV reproduction in mixed infections. Objective — to study the causative agents of acute respiratory viral infections (ARVI) in Moscow during 2011–2022 by reverse transcription with subsequent polymerase chain reaction with fluorescent hydrolysis probes detection in real-time (RT2-PCR). Materials and Methods. Nasopharyngeal swabs from 3908 patients with acute respiratory infections were examined by the RT2-PCR. Results. Monitoring of RV spread in Moscow showed cyclical changes in frequencies with three dominant species: influenza A virus (up to 31.3%), respiratory syncytial virus (up to 24.8%) and human rhinoviruses (up to 21.3%) in 2011–2020. The increase in the portion of unidentified clinical specimens from 1.2 to 28.5% in 2022 indicated incomplete accordance of diagnostic systems to modern RV isolates or the emergence of new species or strains of pathogens. Unidirectional changes in dynamics were registered for 5 out of 9 studied RVs with correlation coefficients of 0.43–0.79. High frequencies of mixed acute respiratory viral infections (up to 33.4%) along with unidentified samples do not allow us to accurately assess the risks of infection with various RV in Moscow, but prove the necessity of preventing infectious diseases with the most common RV. Conclusion. Analysis of the dynamics of RV frequencies in Moscow showed the preservation of the dominant species: influenza A virus, respiratory syncytial virus and human rhinoviruses. During the period of vaccination against COVID-19, the proportion of seasonal coronaviruses increased.","PeriodicalId":508236,"journal":{"name":"Journal of microbiology, epidemiology and immunobiology","volume":"25 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139249564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
D. Bryzgalova, Nikolai A. Sakharnov, M. I. Popkova, Evgeniya A. Soboleva, E. Kulova, Oleg V. Utkin
{"title":"Phylodynamic characteristics of the LMP-1 gene of the Epstein–Barr virus isolated in the Nizhny Novgorod region","authors":"D. Bryzgalova, Nikolai A. Sakharnov, M. I. Popkova, Evgeniya A. Soboleva, E. Kulova, Oleg V. Utkin","doi":"10.36233/0372-9311-379","DOIUrl":"https://doi.org/10.36233/0372-9311-379","url":null,"abstract":"Introduction. Epstein–Barr virus (EBV) is one of the most common herpesviruses and has a pronounced genetic polymorphism. The study of the phylodynamic characteristics of the virus is an important aspect of the study of evolutionary changes in the LMP-1 gene and their consequences. The aim of the work was a philodynamic analysis of EBV isolates from Nizhny Novgorod region based on the C-terminal fragment of the LMP-1 gene. Materials and methods. The study included 158 EBV isolates obtained from blood leukocytes and saliva of children aged 1–17 years with a diagnosis of infectious mononucleosis caused by EBV (n = 68) and apparently healthy children of comparable sex and age (n = 29). LMP-1 genovariants were obtained using the Sanger sequencing method. Comparative analysis of amino acid sequences was performed using the MEGA X program. Philodynamic analysis of the obtained nucleotide sequences and isolates deposited in GenBank was carried out using the BEAST v. 1.10.4 software package. Recombination analysis was performed using the Simplot program. Results. 158 nucleotide sequences of the C-terminal fragment of the LMP-1 gene from Nizhny Novgorod region EBV isolates were obtained and deposited in the GenBank database. The circulation time of the nearest common ancestor for the modified B95-8 genovariants with G212S + E328Q + S366T and NC mutations with the D250N substitution has been established dating back to 1994 and 1923. The rate of evolution of these genovariants was the highest and amounted to 1.298 × 10–4 and 7.868 × 10–4 nucleotide substitutions/site/year. Recombinations were detected in the Nizhny Novgorod region sequences Med-, B95-8, China 1 with mutations G212S, G212S, E214Q, respectively. Conclusion. For the first time, a phylodynamic characterization of Nizhny Novgorod region isolates and LMP-1 EBV genovariants isolated in various regions of the world is given. The data obtained expand the existing understanding of the circulation of EBV LMP-1 genovariants in the territory of the European part of Russia.","PeriodicalId":508236,"journal":{"name":"Journal of microbiology, epidemiology and immunobiology","volume":"78 ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139246541","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
E. Kalinin, Y. Chalenko, P. Safarova, V. A. Fedorova, S. Ermolaeva
{"title":"Analysis of production levels of InlA and InlB invasion factors in Listeria monocytogenes isolates collected in the Russian Federation","authors":"E. Kalinin, Y. Chalenko, P. Safarova, V. A. Fedorova, S. Ermolaeva","doi":"10.36233/0372-9311-397","DOIUrl":"https://doi.org/10.36233/0372-9311-397","url":null,"abstract":"Background. Listeria monocytogenes is characterized by the presence of epidemic hypervirulent clones. A key feature of L. monocytogenes is its capacity to invade non-professional phagocytic cells. Hypervirulent clones are strongly associated with the increased production and/or the presence of certain isoforms of invasion factors InlA and InlB. The purpose of the study is to create a test system for InlA and InlB detection and to measure the InlA and InlB production levels in L. monocytogenes isolates belonging to clonal groups with different virulence potential. Materials and methods. The study was performed using 32 L. monocytogenes strains belonging to epidemic clones ECII, ECIV, ECVII (clonal complexes CC1, CC2, CC7) and hypovirulent clonal complex CC9. Sequencing of inlA and inlB genes was performed. The indirect enzyme-linked immunosorbent assay was used to analyze the production levels of InlA and InlB proteins. Results. The variability of InlA was revealed among strains belonging to the same clonal complex: 3 InlA isoforms were identified among strains belonging to CC7; out of 8 strains belonging to CC9, one strain had a stop codon in the inlA gene, leading to the loss of function of the InlA protein. The differences between inlB alleles correlated with the specificity of strains belonging to a certain clonal complex. Differences in production levels of invasion factors were measured. In strains belonging to CC9, the InlA production level was 2.5 times as low compared to strains belonging to CC1, CC2, and CC7. In strains belonging to phylogenetically related CC1 and CC2, the InlB production level was on average 4 times as high compared to strains belonging to CC7 and CC9. Conclusion. The obtained results confirm the variability of major invasion factors both among clonal complexes and strains of the same complex. The increased production of invasion factors InlA and InlB correlates with the potential virulence of strains.","PeriodicalId":508236,"journal":{"name":"Journal of microbiology, epidemiology and immunobiology","volume":"17 17","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139247865","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. M. Ignatyev, A. Oksanich, E. V. Kazakova, T. G. Samartseva, Еlena V. Otrashevskaya, Stanislav V. Uyba, V. Trukhin
{"title":"Isolation and genetic analysis of the chikungunya virus from Aedes aegypti and Aedes albopictus mosquitoes captured in Central America","authors":"G. M. Ignatyev, A. Oksanich, E. V. Kazakova, T. G. Samartseva, Еlena V. Otrashevskaya, Stanislav V. Uyba, V. Trukhin","doi":"10.36233/0372-9311-354","DOIUrl":"https://doi.org/10.36233/0372-9311-354","url":null,"abstract":"Introduction. The habitat of mosquitoes belonging to the genera Aedes spp., Culex spp., Culiseta spp. is in South and Central America, including Nicaragua. Monitoring of the spread of mosquito vectors and assessment of the infection with arboviruses can provide information on possible occurrence of new diseases or an increase in the reported cases, changes in the infectivity of viruses for humans due to changes in pathogen transmitters. The purpose of this study was isolation and identification of arboviruses belonging to the Flavivirus and Alphavirus genera from A. albopictus, A. aegypti, Culiseta spp., Culex spp. mosquitoes captured in forests of Nicaragua. Materials and methods. A. albopictus, A. aegypti, Culiseta spp., Culex spp. mosquitoes were captured during the dry season in 2021 in forested areas of Nicaragua in four different locations. Mosquitoes were sorted into pools, each containing 5-8 mosquitoes (236 pools in total). Using the reverse transcription polymerase chain reaction, the pools were tested for the presence of chikungunya (CHIKV), dengue, Zika, and yellow fever viruses. Positive pools were inoculated into the C6/36 cell culture to obtain isolates and for their further sequencing. Results. The dengue virus was detected only in Aedes spp. mosquitoes: in 7 pools — A. aegypti, in 1 — A. albopictus. CHIKV was also detected only in Aedes spp. mosquitoes: in 3 pools — A. aegypti, in 1 — A. albopictus. The sequencing of nucleotide sequences of 6К, Е1, Е2, and NS1 genes of CHIKV isolated from A. albopictus mosquitoes showed that compared to the similar gene sequences from CHIKV isolates recovered from A. aegypti mosquitoes, the 6K gene region contained 4 nucleotide and 4 amino acid substitutions, while the E1 region contained 16 nucleotide substitutions, 10 of them led to amino acid substitutions; the E2 region contained 14 nucleotide and 11 amino acid substitutions; the NS1 region contained 33 nucleotide and 19 amino acid substitutions.","PeriodicalId":508236,"journal":{"name":"Journal of microbiology, epidemiology and immunobiology","volume":"6 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139248776","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}