Microbiology Independent Research Journal (MIR Journal)
Not a member yet
79 research outputs found
Sort by
Факторы, влияющие на тяжесть течения COVID-19 и развитие осложнений
Get PDFDue to the prevalence and diversity of both symptoms and outcomes of COVID-19, the understanding of the factors that determine the risk of severe course of this disease and possible complications is of particular importance. In this review, we present the information on specifics of COVID-19 pathogenesis and give a theoretical justification for the factors that determine the course of this disease in patients of different age groups, patients with chronic pathology, and pregnant women. Particular attention is paid to the post-COVID syndrome.В связи с широким распространением и «многоликостью» как симптоматики, так и исходов COVID-19 особую актуальность приобретает понимание факторов, определяющих риск тяжелого течения заболевания и возможных осложнений. В обзоре представлена информация об особенностях патогенеза COVID-19, дали теоретическое обоснование факторов, обусловливающих особенности заболевания у пациентов разных возрастных групп, беременных, а также при хронических патологиях. Отдельное внимание уделено постковидному синдрому
Фено- и генотипический портрет штаммов Yersinia pestis филогрупп 2.MED4 и 2.MED1 – этиологических агентов вспышек чумы ХХ века в Прикаспийском регионе
Get PDFWe performed a comparative analysis of the phenotypic and genotypic characteristics of strains of the plague pathogen of phylogroups 2.MED4 and 2.MED1 of the medieval biovar of the main subspecies from epidemically active plague foci in the Caspian Sea region in the XX century. According to the results of the analysis, biochemical properties, nutritional requirements and plasmid profile of strains of phylogroups 2.MED4 and 2.MED1 of the medieval biovar of Y. pestis were determined. Genetic variability in the hemS, caf1M, and ssaJ genes associated with the virulence in strains of the 2.MED lineage was revealed. The data obtained on the phenotypic and genotypic characteristics of the medieval biovar of the plague microbe can be used in laboratory diagnostics of the plague microbe and will contribute to the study of genome changing in the process of microevolution of this highly virulent biovar.Проведен сравнительный анализ фенотипических и генотипических характеристик штаммов возбудителя чумы филогрупп 2.MED4 и 2.MED1 средневекового биовара основного подвида из эпидемически активных в ХХ веке очагов чумы Прикаспийского региона. По результатам анализа определены биохимические свойства, питательные потребности и плазмидный профиль штаммов филогрупп 2.MED4 и 2.MED1 средневекового биовара Y. pestis. Выявлена генетическая вариабельность в генах hemS, caf1М и ssaJ, ассоциированных с вирулентностью, у штаммов линии 2.MED. Полученные данные по фенотипическим и генотипическим характеристикам средневекового биовара могут найти свое применение в лабораторной диагностике чумного микроба и внесут вклад в исследование преобразований генома в процессе микроэволюции этого высоковирулентного биовара
Деконтаминация поверхностей от нуклеиновых кислот аэрозолями дезинфицирующих средств
Get PDFCross-contamination that leads to false positive results is a serious problem for laboratories using the PCR method. There are many ways to solve this problem, but none of them could be considered universal. Treatment with aerosols is the preferable method for decontamination of large areas of complex surfaces. The goal of this study was to determine effective aerosol compositions and regimens for the decontamination of nucleic acids on laboratory surfaces. The decontaminating activity of compounds that release active chlorine and active oxygen was studied using model surfaces contaminated with nucleic acids and bacteria. Effective modes of decontamination with aerosols were established by analysis of obtained experimental data. Differences between decontamination of nucleic acids and bacterial disinfection of the laboratory surfaces are shown.Важной проблемой при работе в ПЦР-лаборатории является возникновение перекрестного загрязнения, которое приводит к появлению ложноположительных результатов. Существует множество способов решения данной проблемы, однако ни один из них не является универсальным. Для деконтаминации сложных поверхностей большой площади предпочтительнее использовать аэрозольный метод обработки. Цель данного исследования заключалась в определении эффективных режимов применения дезинфицирующих средств для деконтаминации от нуклеиновых кислот аэрозольным методом. Анализ деконтаминирующей активности хлорактивных и кислородактивных соединений проводили, моделируя контаминацию поверхностей нуклеиновыми кислотами и бактериями. В процессе работы установлены эффективные режимы проведения аэрозольной деконтаминации. Показаны различия при удалении нуклеиновых кислот и бактериального загрязнения с лабораторных поверхностей
Three cases of Actinomyces isolation from the eye lesions of patients with a chronic and recurrent ophthalmic infection
Get PDFActinomycosis is an indolent, slowly progressive infection caused by Gram-positive facultative anaerobic bacteria from the genus Actinomyces. These bacteria have been reported as a cause of ophthalmic infections such as endophthalmitis, keratitis, and canaliculitis. The objective of the present study was to investigate the pattern and antibiotic sensitivity profile of anaerobes isolated from lesions in the medial canthus of the eye.Three pus aspirate samples (from eye) were delivered to a microbiology laboratory in a strict anaerobic condition in Robertson Cooked Meat media (RCM). The samples were inoculated on Blood Agar and incubated anaerobically in a Gas Pack Jar incubator at 5%-10% CO2 and in aerobic condition at 37°C. Pure colonies isolated on anaerobically incubated plates were identified by the VITEK® 2 COMPACT system. Antibiotic sensitivity testing was conducted using an Epsilometer-strip test.Three isolates identified and confirmed with the help of VITEK® 2 were Actinomyces israelii, Actinomyces odontolyticus, and Actinomyces meyeri. All three species of Actinomyces were sensitive to Vancomycin, Moxifloxacin, and Imipenem, but they were resistant to Metronidazole.Since there have been several cases of anaerobic ophthalmic infections reported to date, samples from patients with chronic eye infections should be analyzed for anaerobic culture for correct diagnosis and proper treatment. Moxifloxacin but not Metronidazole is a suitable drug for the treatment of anaerobic eye infection. Actinomycosis is an indolent, slowly progressive infection caused by Gram-positive facultative anaerobic bacteria from the genus Actinomyces. These bacteria have been reported as a cause of ophthalmic infections such as endophthalmitis, keratitis, and canaliculitis. The objective of the present study was to investigate the pattern and antibiotic sensitivity profile of anaerobes isolated from lesions in the medial canthus of the eye.Three pus aspirate samples (from eye) were delivered to a microbiology laboratory in a strict anaerobic condition in Robertson Cooked Meat media (RCM). The samples were inoculated on Blood Agar and incubated anaerobically in a Gas Pack Jar incubator at 5%-10% CO2 and in aerobic condition at 37°C. Pure colonies isolated on anaerobically incubated plates were identified by the VITEK® 2 COMPACT system. Antibiotic sensitivity testing was conducted using an Epsilometer-strip test.Three isolates identified and confirmed with the help of VITEK® 2 were Actinomyces israelii, Actinomyces odontolyticus, and Actinomyces meyeri. All three species of Actinomyces were sensitive to Vancomycin, Moxifloxacin, and Imipenem, but they were resistant to Metronidazole.Since there have been several cases of anaerobic ophthalmic infections reported to date, samples from patients with chronic eye infections should be analyzed for anaerobic culture for correct diagnosis and proper treatment. Moxifloxacin but not Metronidazole is a suitable drug for the treatment of anaerobic eye infection.
Антимикробные пептиды и белки в биожидкостях человека
Get PDFAntimicrobial peptides and proteins (AMPs) are endogenous compounds that have a direct antimicrobial effect on bacteria (e. g., by disrupting bacterial membranes), as well as on fungi and viruses. AMPs are the main component of the innate immunity of living organisms and are produced by both epithelial cells (skin cells, cells of respiratory tract, intestine, urinary and genital tracts) and cells of the immune system and are secreted into secretory fluids. AMPs can also act as chemoattractants for immunocompetent cells (neutrophils, monocytes, T lymphocytes, dendritic cells) in the inflammation site and affect the antigen presenting cells by modulating adaptive T cell immune responses. The representatives of the main 15 AMP classes, that we describe in this review, are the most studied group of the large pool of these compounds. We discuss their localization, expression, and concentration in various biofluids of humans under normal and pathological conditions.Антимикробные пептиды и белки (АМПБ) – это эндогенные соединения, оказывающие прямое противомикробное действие на бактерии, а также на грибы и вирусы. АМПБ являются основным компонентом врожденного иммунитета живых организмов и вырабатываются как эпителиальными клетками (клетки кожи, дыхательных путей, кишечника, мочевыводящих и половых путей), так и клетками иммунной системы, и выделяются в секреторные жидкости. Помимо антимикробной функции АМПБ могут выполнять роль хемоаттрактантов иммунокомпетентных клеток (нейтрофилы, моноциты, Т лимфоциты, дендритные клетки) в очаг воспаления. АМПБ оказывают влияние также на антигенпрезентирующие клетки, модулируя адаптивные T-клеточные иммунные ответы. Из большого количества описанных АМПБ наиболее изученными являются 15 основных классов, которые мы рассматриваем в данном обзоре, включая их локализацию, экспрессию и концентрацию в различных биожидкостях в норме и при патологии
Antibiotic-resistant salmonellae in pet reptiles in Saudi Arabia
Get PDFWe investigated the occurrence rate of antibiotic-resistant salmonellae in exotic pet reptiles in Saudi Arabia. Salmonellae samples were collected from eight different genera of pet reptiles (snakes and lizards). Selective enrichment and selective plating procedures were carried out in order to detect salmonellae. Isolated bacteria were identified using biochemical tests, API 20E strips, and the VITEK compact system. Antimicrobial susceptibility testing was performed using the disc diffusion method. Salmonella spp. belonging to subspecies I (Salmonella enterica ssp. enterica) were detected in 29.2% of the samples. All of the detected salmonellae showed multidrug resistance (p<0.001, χ2 ). The results demonstrated that pet reptiles in private households could present health hazards to humans. Therefore, these animals should be carefully handled to avoid infection. To the best of our knowledge, this is the first report regarding the occurrence rate of antibiotic-resistant salmonellae in pet reptiles in Saudi Arabia. The detected Salmonella serovars should be subjected to further in-depth molecular analyses in order to understand the overall epidemiology of salmonellosis in Saudi Arabia.We investigated the occurrence rate of antibiotic-resistant salmonellae in exotic pet reptiles in Saudi Arabia. Salmonellae samples were collected from eight different genera of pet reptiles (snakes and lizards). Selective enrichment and selective plating procedures were carried out in order to detect salmonellae. Isolated bacteria were identified using biochemical tests, API 20E strips, and the VITEK compact system. Antimicrobial susceptibility testing was performed using the disc diffusion method. Salmonella spp. belonging to subspecies I (Salmonella enterica ssp. enterica) were detected in 29.2% of the samples. All of the detected salmonellae showed multidrug resistance (p<0.001, χ2 ). The results demonstrated that pet reptiles in private households could present health hazards to humans. Therefore, these animals should be carefully handled to avoid infection. To the best of our knowledge, this is the first report regarding the occurrence rate of antibiotic-resistant salmonellae in pet reptiles in Saudi Arabia. The detected Salmonella serovars should be subjected to further in-depth molecular analyses in order to understand the overall epidemiology of salmonellosis in Saudi Arabia
Фармакодинамическая активность нового соединения XC221GI в in vitro и in vivo моделях вирусного воспаления респираторного тракта
Get PDFThe viruses most commonly affecting the human respiratory tract include rhinoviruses, respiratory syncytial virus (RSV), influenza viruses, and coronaviruses (CoVs). The virus infection of the epithelial cells of the respiratory tract triggers an inflammation accompanied by the release of pro-inflammatory cytokines and chemokines including IL6, IL8(CXCL8), IL1β, and tumor necrosis factor α (TNFα). A subsequent acute inflammatory response in the lungs is accompanied by an increase in the production of cytokines and chemokines − CXCR3 receptor ligands – that are key players of acute inflammatory response that induce an influx of neutrophils and T cells into the lungs.We studied the pharmacodynamic activity of the new compound XC221GI to suppress the IL6 and IL8 of an experimental RSV infection in vitro in human lung carcinoma cells A549 and in vivo in the lungs of cotton rats. We also studied the effect of XC221GI on the production of the chemokines CXCL10, CXCL9, and CXCL11 in mouse bronchoalveolar lavage as well as on the influx of neutrophils into the mouse lungs after the intranasal administration of interferon γ (IFNγ).The obtained results demonstrate the anti-inflammatory activity of XC221GI, which suppresses the production of excessive levels of the key inflammatory markers IL6, IL8, CXCL10, CXCL9, and CXCL11 as well as the influx of neutrophils into the lungs thereby reducing lung pathology. These data confirm the effectiveness of XC221GI as a means of preventive anti-inflammatory therapy during a viral infection of the respiratory tract.Вирусы, наиболее часто поражающие респираторный тракт человека, включают риновирусы, респираторно-синцитиальный вирус (РСВ), вирусы гриппа и коронавирусы (CoV). Инфицирование вирусом эпителиальных клеток респираторного тракта запускает воспалительный процесс, сопровождающийся выбросом провоспалительных цитокинов и хемокинов, основными из которых являются интерлейкины IL6, IL8(CXCL8), IL1β и фактор некроза опухоли (tumor necrosis factor α, TNFα). Переход инфекции в фазу острой воспалительной реакции в легких сопровождается увеличением продукции цитокинов, притоком в легкие нейтрофилов и Т-клеток и индукцией хемокинов – лигандов рецептора CXCR3, – основных участников генерализованного воспаления.В настоящей работе мы изучили фармакодинамическую активность нового соединения XC221GI в отношении IL6 и IL8 в условиях экспериментальной РСВ инфекции in vitro в клетках карциномы легкого человека А549 и in vivo в легких хлопковых крыс. Мы также изучили влияние XC221GI на приток нейтрофилов в легкие мышей и индукцию хемокинов CXCL10, CXCL9 и CXCL11 в бронхоальвеолярном лаваже после интраназального введения животным интерферона γ (IFNγ).В ходе исследования была продемонстрирована противовоспалительная активность препарата XC221GI, выражающаяся в снижении избыточной продукции ключевых маркеров воспаления в легких, включающих цитокины и хемокины IL6, IL8, CXCL10, CXCL9, CXCL11 и нейтрофилы, приводя к снижению легочной патологии. Полученные результаты подтверждают эффективность препарата XC221GI в качестве средства упреждающей противовоспалительной терапии при вирусной инфекции респираторного тракта
Identification and distribution of anaerobic bacteria isolated from clinical specimens in a University Hospital: 4 years’ experience
Get PDFAnaerobes, which are components of microbiota, can cause life-threatening infections. Because of their fastidious nature, they are difficult to isolate and are often overlooked. The goal of this study was to identify the anaerobic bacteria isolated from clinical specimens at the Central Laboratory of Hacettepe University Hospital in 2015-2018 and to evaluate the distribution of the isolated bacterial species among the different specimen types. The anaerobic bacteria isolated from the specimens were identified by the conventional methods and MALDI-TOF MS.Overall, 15,300 anaerobic cultures were studied. Of these, 14,434 (94.3%) were blood samples and 866 (5.7%) were other clinical specimens. A total of 138 anaerobic bacteria were isolated: 62 (44.9%) were isolated from blood samples and 76 (55.1%) from other specimens. The most isolated anaerobes from blood cultures were Bacteroides spp. (41.9%), followed by Cutibacterium acnes (25.8%) and Clostridium spp. (9.7%). The most isolated anaerobes from the other specimens were Gram-negative bacilli, including Bacteroides spp. (15.8%), Fusobacterium spp. (14.5%), Prevotella spp. (14.5%), and Porphyromonas spp. (2.6%). Anaerobic Finegoldia magna represented the major species among the isolated Gram-positive bacteria (10.5%). Anaerobic growth was observed in 0.4% of all the blood cultures and in 5.8% of the positive blood cultures. The results of our study showed that the incidence of anaerobic bacteremia was stable during the 2015-2018 period.Anaerobes, which are components of microbiota, can cause life-threatening infections. Because of their fastidious nature, they are difficult to isolate and are often overlooked. The goal of this study was to identify the anaerobic bacteria isolated from clinical specimens at the Central Laboratory of Hacettepe University Hospital in 2015-2018 and to evaluate the distribution of the isolated bacterial species among the different specimen types. The anaerobic bacteria isolated from the specimens were identified by the conventional methods and MALDI-TOF MS.Overall, 15,300 anaerobic cultures were studied. Of these, 14,434 (94.3%) were blood samples and 866 (5.7%) were other clinical specimens. A total of 138 anaerobic bacteria were isolated: 62 (44.9%) were isolated from blood samples and 76 (55.1%) from other specimens. The most isolated anaerobes from blood cultures were Bacteroides spp. (41.9%), followed by Cutibacterium acnes (25.8%) and Clostridium spp. (9.7%). The most isolated anaerobes from the other specimens were Gram-negative bacilli, including Bacteroides spp. (15.8%), Fusobacterium spp. (14.5%), Prevotella spp. (14.5%), and Porphyromonas spp. (2.6%). Anaerobic Finegoldia magna represented the major species among the isolated Gram-positive bacteria (10.5%). Anaerobic growth was observed in 0.4% of all the blood cultures and in 5.8% of the positive blood cultures. The results of our study showed that the incidence of anaerobic bacteremia was stable during the 2015-2018 period
Gut microbiome of healthy people and patients with hematological malignancies in Belarus
Get PDFoai:oai.mirjournal.elpub.ru:article/98Gut microbiota plays an important role in human health and the development of various diseases. We describe the intestinal microbiome of 31 healthy individuals and 29 patients who have hematological malignancies from Belarus. Bacteria that belong to Faecalibacterium, Blautia, Bacteroides, Ruminococcus, Bifidobacterium, Prevotella, Lactobacillus, and Alistipes genera were predominant in the gut of healthy people. Based on the dominant microbiota species, two enterotype-like clusters that are driven by Bacteroides and Blautia, respectively, were identified. A significant decrease in alpha diversity and alterations in the taxonomic composition of the intestinal microbiota were observed in patients with hematological malignancies compared to healthy people. The microbiome of these patients contained a high proportion of Bacteroides, Blautia, Faecalibacterium, Lactobacillus, Prevotella, Alistipes, Enterococcus, Escherichia-Shigella, Ruminococcus gnavus group, Streptococcus, and Roseburia. An increased relative abundance of Bacteroides vulgatus, Ruminococcus torques, Veillonella, Tuzzerella, Sellimonas, and a decreased number of Akkermansia, Coprococcus, Roseburia, Agathobacter, Lachnoclostridium, and Dorea were observed in individuals with hematological malignancies. Generally, the composition of the gut microbiome in patients was more variable than that of healthy individuals, and alterations in the abundance of certain microbial taxa were individually specific.Gut microbiota plays an important role in human health and the development of various diseases. We describe the intestinal microbiome of 31 healthy individuals and 29 patients who have hematological malignancies from Belarus. Bacteria that belong to Faecalibacterium, Blautia, Bacteroides, Ruminococcus, Bifidobacterium, Prevotella, Lactobacillus, and Alistipes genera were predominant in the gut of healthy people. Based on the dominant microbiota species, two enterotype-like clusters that are driven by Bacteroides and Blautia, respectively, were identified. A significant decrease in alpha diversity and alterations in the taxonomic composition of the intestinal microbiota were observed in patients with hematological malignancies compared to healthy people. The microbiome of these patients contained a high proportion of Bacteroides, Blautia, Faecalibacterium, Lactobacillus, Prevotella, Alistipes, Enterococcus, Escherichia-Shigella, Ruminococcus gnavus group, Streptococcus, and Roseburia. An increased relative abundance of Bacteroides vulgatus, Ruminococcus torques, Veillonella, Tuzzerella, Sellimonas, and a decreased number of Akkermansia, Coprococcus, Roseburia, Agathobacter, Lachnoclostridium, and Dorea were observed in individuals with hematological malignancies. Generally, the composition of the gut microbiome in patients was more variable than that of healthy individuals, and alterations in the abundance of certain microbial taxa were individually specific
Оценка состояния микробиома у лиц пожилого возраста с нарушениями углеводного и липидного обмена методом микробиом-ассоциированной экспосомики
Get PDFA biochemical analysis of blood and a study of the chemical composition of the blood samples of 163 people 45–90 years old with type 2 diabetes mellitus and dyslipidemia was conducted. The concentrations of the following compounds in the blood were determined: fatty acids, aldehydes, and styrenes of microbial origin as well as the levels of glucose triglycerides, cholesterol, and lipids of low and high density. The chemical composition of blood was determined by gas chromatography-mass spectrometry. The concentrations of fatty acids, aldehydes, and styrenes were used to calculate the total molar concentration of chemical compounds, the concentration of octadecene aldehyde (18a), the total concentration of hydroxy acids of derivatives of the hydroxyl residue of lipid A of bacterial endotoxin (3OH-FA), and the grouped total concentrations of chemical compounds of microbial origin, which determine the representation of the main four phylotypes of the human microbiome: Actinobacteria, Bacteroidetes, Proteobacteria, and Firmicutes.As a result of the study, data were obtained on an increase in the total concentration of chemical compounds, the concentration of octadecene aldehyde, and the concentration of 3OH-FA in violation of carbohydrate metabolism by the type of diabetes mellitus type 2. There was a decrease in the representation of Bacteroidetes in violation of carbohydrate metabolism and a decrease in the representation of Proteobacteria, Firmicutes in violation of carbohydrate and lipid metabolism, and an increase in the representation of Actinobacteria in violation of lipid metabolism, including those combined with a violation of carbohydrate metabolism.In patients with type 2 diabetes mellitus and in the control group, there was an inverse correlation between the presence of Firmicutes and blood glucose levels. In the type 2 diabetes mellitus group, there was a direct correlation between the representation of Bacteroidetes and the level of triglycerides in the blood.In patients with lipid metabolism disorders, we did not reveal statistically significant changes in the concentrations of microbial markers in the blood of patients nor statistically significant correlations between the biochemical blood parameters and the representation of microbiome phylotypes.Проведены биохимический анализ крови и исследование химического состава образцов крови 163 пациентов в возрасте 45–90 лет с сахарным диабетом 2-го типа и дислипидемиями. В крови определяли концентрации жирных кислот, альдегидов, стиролов, имеющих микробное происхождение, а также уровни глюкозы, триглицеридов, холестерина, липидов низкой и высокой плотности. Химический состав крови определяли методом газовой хромато-масс-спектрометрии. По концентрациям жирных кислот, альдегидов, стиролов рассчитывали суммарную молярную концентрацию малых молекул микробного происхождения (Small molecules originating from microbes, SMOM), концентрацию октадеценового альдегида (18a), суммарную концентрацию гидроксикислот, производных гидроксильного остатка липида А, бактериального эндотоксина (3OH-FA) и сгруппированные суммарные концентрации химических соединений микробного происхождения, определяющих представительство основных четырех филотипов микробиома человека: Actinobacteria, Bacteroidetes, Proteobacteria, Firmicutes.В результате исследования были получены данные об увеличении суммарной концентрации химических соединений, концентрации октадеценового альдегида и концентрации 3OH-FA у пациентов при нарушении углеводного обмена по типу сахарного диабета 2-го типа. Снижение представленности Bacteroidetes отмечали при нарушении углеводного обмена и снижение представленности Proteobacteria и Firmicutes – при нарушении углеводного и липидного обменов, а также увеличение представленности Actinobacteria – при нарушении липидного обмена, в том числе сочетанного с нарушением углеводного обмена. У пациентов с сахарным диабетом 2-го типа и в контрольной группе отмечена обратная корреляция между представленностью Firmicutes и уровнем глюкозы в крови. В группе пациентов с сахарным диабетом 2-го типа отмечена прямая корреляция представленности Bacteroidetes и уровня триглицеридов в крови.При нарушениях липидного обмена не выявлено ни статистически значимых изменений концентраций микробных маркеров в крови пациентов, ни статистически значимых корреляционных связей биохимических параметров крови и представленности филотипов микробиом