E. Poluektova - Academia.edu (original) (raw)
Papers by E. Poluektova
World Journal of Gastroenterology
Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder in which recurrent abdom... more Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder in which recurrent abdominal pain is associated with defecation or a change in bowel habits (constipation, diarrhea, or both), and it is often accompanied by symptoms of abdominal bloating and distension. IBS is an important health care issue because it negatively affects the quality of life of patients and places a considerable financial burden on health care systems. Despite extensive research, the etiology and underlying pathophysiology of IBS remain incompletely understood. Proposed mechanisms involved in its pathogenesis include increased intestinal permeability, changes in the immune system, visceral hypersensitivity, impaired gut motility, and emotional disorders. Recently, accumulating evidence has highlighted the important role of the gut microbiota in the development of IBS. Microbial dysbiosis within the gut is thought to contribute to all aspects of its multifactorial pathogenesis. The last few decades have also seen an increasing interest in the impact of antibiotics on the gut microbiota. Moreover, antibiotics have been suggested to play a role in the development of IBS. Extensive research has established that antibacterial therapy induces remarkable shifts in the bacterial community composition that are quite similar to those observed in IBS. This suggestion is further supported by data from cohort and case-control studies, indicating that antibiotic treatment is associated with an increased risk of IBS. This paper summarizes the main findings on this issue and contributes to a deeper understanding of the link between antibiotic use and the development of IBS.
PLOS ONE, 2021
Background Irritable bowel syndrome (IBS) is a pathologic condition characterized by changes in g... more Background Irritable bowel syndrome (IBS) is a pathologic condition characterized by changes in gut microbiome composition, low-grade inflammation, and disruption of intestinal wall permeability. The interaction between the gut microbiome and the disease manifestation remains unclear. The changing of tight junction proteins and cytokines expression throughout the gastrointestinal tract in IBS patients has not been studied yet. Aim of the study To assess the changes of gut microbiome composition, tight junction proteins, and cytokines expression of intestinal mucosa from the duodenum to the distal part of the colon in IBS patients and healthy volunteers. Methods In 31 IBS patients (16 patients with IBS-D; 15 patients with IBS-C) and 10 healthy volunteers the expression of CLD-2, CLD-3, CLD-5, IL-2, IL-10, and TNF-α in mucosal biopsy specimens was determined by morphological and immune-histochemical methods. The qualitative and quantitative composition of the intestinal microbiota was...
Background. Hemodynamic changes (hyperdynamic circulation) and gut dysbiosis are observed in cirr... more Background. Hemodynamic changes (hyperdynamic circulation) and gut dysbiosis are observed in cirrhosis. It was suggested that gut dysbiosis contributes to the development of hyperdynamic circulation, which aggravates the course of cirrhosis. The aim is to test this hypothesis.Methods. The cross-sectional observational study included 47 patients with cirrhosis. Stool microbiome was assessed using 16S rRNA gene sequencing. Echocardiography with a simultaneous assessment of blood pressure and heart rate was performed. Hemodynamic parameters were calculated. Results. Hyperdynamic circulation was found in 34% of patients. Patients with hyperdynamic circulation had higher incidences of clinically significant ascites (p=0.018), overt hepatic encephalopathy (p=0.042), hypoalbuminemia (p=0.011), hypoprothrombinemia (p=0.019), systemic inflammation (p=0.002), and severe hyperbilirubinemia (p=0.042) than patients without hyperdynamic circulation. The abundance of Proteobacteria (p=0.012), Ente...
Minerva Gastroenterology, 2021
Russian Journal of Gastroenterology, Hepatology, Coloproctology, 2020
Aim. The study reviews current evidence on digestive system lesions provoked by the new COVID-19 ... more Aim. The study reviews current evidence on digestive system lesions provoked by the new COVID-19 coronavirus infection.Key points. Alongside the destructive impact on respiratory system, COVID-19 manifests itself in gastrointestinal symptoms (nausea, vomiting, diarrhoea) that may precede respiratory signs and prevail in the clinical picture of infection. Patients with chronic inflammatory bowel diseases receiving immunosuppressive therapy are at elevated risk of severe COVID-19 progression. The new coronavirus infection may induce liver damage with increased transaminase activity.Conclusion. Association of digestive system lesions with COVID-19 remains understudied and requires further research.
Russian Journal of Gastroenterology, Hepatology, Coloproctology, 2020
Цель обзора. Представить причины нарушения проницаемости слизисто-эпителиального барьера и рассмо... more Цель обзора. Представить причины нарушения проницаемости слизисто-эпителиального барьера и рассмотреть их как патогенетический фактор развития функциональных заболеваний желудочно-кишечного тракта (ЖКТ). Основные положения. Слизисто-эпителиальный барьер ЖКТ включает в себя несколько компонентов: преэпителиальная защита-слой слизи, покрывающей эпителий; эпителиальная защита, к которой относится высокая регенерация эпителия и плотные межклеточные контакты; постэпителиальная защита-клетки иммунной системы и кровеносные сосуды. Состав кишечной микробиоты также может рассматриваться как часть слизисто-эпителиального барьера. У пациентов с функциональной диспепсией (ФД) и синдромом раздраженного кишечника (СРК) определяется ряд морфологических изменений. Так, у пациентов с ФД выявлено изменение экспрессии белков, образующих межэпителиальные контакты (клаудин-1, zonula occludens, окклюдин, Е-кадгерин, β-катенин и десмоглин-2), а у пациентов с СРК-повышенная экспрессия клаудина-2. Нарушение проницаемости приводит к развитию воспалительных изменений в кишечной стенке, в результате которых формируются висцеральная и центральная сенситизация, а также нарушение моторики кишечника, что, в свою очередь, приводит к развитию симптомов СРК и ФД. Заключение: нарушение барьерной функции слизисто-эпителиального слоя ЖКТ может рассматриваться как один из патогенетических факторов развития ФД и СРК. Ключевые слова: синдром раздраженного кишечника, функциональная диспепсия, слизисто-эпителиальный барьер, кишечная проницаемость Конфликт интересов: авторы заявляют об отсутствии конфликта интересов. Для цитирования: Ковалева А.Л., Полуэктова Е.А., Шифрин О.С. Кишечный барьер, кишечная проницаемость, неспецифическое воспаление и их роль в формировании функциональных заболеваний желудочно-кишечного тракта. Российской гастроэнтерологической ассоциации по диагностике и лечению гастроэзофагеальной рефлюксной болезни.
Applied Biochemistry and Microbiology, 2019
A simple HPLC technique for the quantitative determination of phytotoxins (stagonolide A and herb... more A simple HPLC technique for the quantitative determination of phytotoxins (stagonolide A and herbarumin I) in liquid culture of the fungus Stagonospora cirsii S-47 has been developed. Some examples of its application are given. The technique was tested in a study of effects of the concentration of refined sunflower oil and the cultivation duration on the production level of these toxins. At an oil concentration of 0.5% or higher in modified Czapek medium with vitamins, the accumulation of S. cirsii biomass and the concentration of stagonolide A increased, while the concentration of herbarumin I decreased. Maximal amounts of both phytotoxins were obtained on the tenth day of submerged S. cirsii cultivation in flasks. When S. cirsii was grown in the same medium supplied with 1% of oil in a laboratory bioreactor, the maximal concentration of stagonolide A (116 mg/L) in the liquid culture was achieved after 5 days of fermentation followed by its considerable reduction after 6 days, while after 7 days of the submerged growth the maximal content of herbarumin I (116 mg/L) increased sharply. The technique of the phytotoxins analysis was used to monitor them during their isolation, as well as for preparative HPLC.
Ontogenez
When rearing the D. virilis larvae on the nutrient medium with 5-bromodeoxyuridine-6-3H (3H-BDU) ... more When rearing the D. virilis larvae on the nutrient medium with 5-bromodeoxyuridine-6-3H (3H-BDU) at different developmental stages, it was found that the intensity of isotope incorporation in the chromosomes and cytoplasm of the salivary gland cells depended on the duration of effect and concentration. The distribution of label along the chromosomes does not occur at random. The spectrum of isotope incorporation is specific for each chromosome. All regions which changed their puffing pattern as a result of rearing the larvae on the medium with 3H-BDU incorporated the isotope and the frequency of incorporation in the most of them differed reliably from the random one. The intensity of incorporation increased with the duration of labelling and the isotope concentration.
Genetika, 1977
The expressivity and temporal patterns of function of the various puff groups are changed, when l... more The expressivity and temporal patterns of function of the various puff groups are changed, when larvae of Drosophila virilis are kept on BUdR containing medium during different periods of their larval development, as compared with the control animals kept on BUdR-free media. The magnitude of the effect depends on the stage at which the treatment is conducted; the larvae of the 3rd instar are more sensitive to BUdR. The effect of BUdR becomes considerably lower by the end of the 3rd instar period.
Power Technology and Engineering, 2011
A method of estimating the effect of the modes of operation of the automatic secondary frequency ... more A method of estimating the effect of the modes of operation of the automatic secondary frequency and power regulation and of the normalized primary frequency regulation on the efficiency of the boiler and the consumption of electric power for individual needs is proposed. The increase in the operating costs of a thermal power station due to the participation of the power units participating in the frequency and power regulation is given.
Applied Biochemistry and Microbiology
The global probiotics industry has been undergoing major changes in recent years. Approaches to f... more The global probiotics industry has been undergoing major changes in recent years. Approaches to finding and creating new probiotics, as well as a paradigm of their use in food, medicine, and pharmacology are changing. The catalyst proved to be the increasing popularity and availability of omics technologies, in particular, metagenomic studies of human and animal microbiomes. However, the efficiency and safety of drugs based on probiotic strains, as well as their marketing rates, largely depend on the levels of legal and technical regulation in the field. The present review discusses the aspects of legal regulation in Russia, the European Union and the United States, along with the advantages and disadvantages of probiotics and postbiotics. A consensus is emerging that postbiotics have a number of advantages over classical live probiotic cultures. The review also focuses on the lactobacilli family, which includes the largest number of probiotic strains studied so far and still holds a leading position among probiotics. On the legislative front, Russia is often ahead of its time with adopting such laws as the Federal Law No. 492-FZ on biosecurity, which defined the concept of human and animal microbiota and set forth legislative guidelines for its preservation. The new field of research referred to as microbiome nutrigenomics aims to achieve this goal.
BMC Microbiology, 2019
Background: All living organisms experience physiological changes regulated by endogenous circadi... more Background: All living organisms experience physiological changes regulated by endogenous circadian rhythms. The main factor controlling the circadian clock is the duration of daylight. The aim of this research was to identify the impact of various lighting conditions on physiological parameters and gut microbiota composition in rats. 3 groups of outbred rats were subjected to normal light-dark cycles, darkness and constant lighting. Results: After 1 and 3 months we studied urinary catecholamine levels in rats; indicators of lipid peroxidation and antioxidant activity in the blood; protein levels of BMAL1, CLOCK and THRA in the hypothalamus; composition and functional activity of the gut microbiota. Subjecting the rats to conditions promoting desynchronosis for 3 months caused disruptions in homeostasis. Conclusions: Changing the lighting conditions led to changes in almost all the physiological parameters that we studied. Catecholamines can be regarded as a synchronization super system of split-level circadian oscillators. We established a correlation between hypothalamic levels of Bmal1 and urinary catecholamine concentrations. The magnitude of changes in the GM taxonomic composition was different for LL/LD and DD/LD but the direction of these changes was similar. As for the predicted functional properties of the GM which characterize its metabolic activity, they didn't change as dramatically as the taxonomic composition. All differences may be viewed as a compensatory reaction to new environmental conditions and the organism has adapted to those conditions.
World journal of microbiology & biotechnology, Jan 17, 2018
Oxidative stress cause serious damages in human organism resulting in multiple diseases. Antioxid... more Oxidative stress cause serious damages in human organism resulting in multiple diseases. Antioxidant therapy includes diet, the use of chemical agents or commensal bacteria such as lactobacilli. This study aims to evaluate the antioxidant (AO) activity of cell-free culture supernatants of lactobacilli, isolated from different parts of the human body. A test system based on Escherichia coli MG1655 strains carrying plasmids encoding luminescent biosensors pSoxS-lux and pKatG-lux inducible by superoxide anion and hydrogen peroxide, respectively, was used to analyze cell-free culture supernatants of lactobacilli. Bioluminescent detection systems are suitable for quick screening of AO activity of lactobacilli. The majority of strains (51 out of 81) belonging to six different species demonstrated various levels of antioxidant activity. This activity was confirmed using the trolox equivalent method. The genome of one of the strains showing high AO activity was sequenced, and the genes puta...
Journal of basic microbiology, 2015
Lactobacilli are important microorganisms in various activities, for example, diary products, mea... more Lactobacilli are important microorganisms in various activities, for example, diary products, meat ripening, bread and pickles, but, moreover, are associated directly with human skin and cavities (e.g., mouth, gut, or vagina). Some of them are used as probiotics. Therefore, the molecular biological investigation of these bacteria is important. Earlier we described several toxin antitoxin systems (type II) in lactobacilli. Here, we describe the structure and transcriptional regulation of genes, encoding TA system YefM-YoeBLrh in three strains of Lactobacillus rhamnosus comparing stationary and exponential growth phases, the influence of stress factors and mRNA stability. The same TA system is responding to physiological and stress conditions differently in related strains. Using primer extension and RLM-RACE methods we determined three transcription start sites of RNAs in the operon. The promoter region of the operon is preceded by a conserved BOX element occurring at multiple positi...
PeerJ, 2019
Recent research has indicated that in addition to the unique genotype each individual may also ha... more Recent research has indicated that in addition to the unique genotype each individual may also have a unique microbiota composition. Difference in microbiota composition may emerge from both its species and strain constituents. It is important to know the precise composition especially for the gut microbiota (GM), since it can contribute to the health assessment, personalized treatment, and disease prevention for individuals and groups (cohorts). The existing methods for species and strain composition in microbiota are not always precise and usually not so easy to use. Probiotic bacteria of the genus Bifidobacterium and Lactobacillus make an essential component of human GM. Previously we have shown that in certain Bifidobacterium and Lactobacillus species the RelBE and MazEF superfamily of toxin-antitoxin (TA) systems may be used as functional biomarkers to differentiate these groups of bacteria at the species and strain levels. We have composed a database of TA genes of these super...
Microorganisms, 2020
We report that the results of our study indicate that Lactobacillus brevis 47 f strain isolated f... more We report that the results of our study indicate that Lactobacillus brevis 47 f strain isolated from the faeces of a healthy individual prevents the manifestations of experimental mucositis induced by treatment of Balb/c mice with the anticancer drug 5-fluorouracil (5 FU; 100 mg/kg i.p. × 3 days). The presence of damage to the intestine and the colon was determined by a morphometric analysis of specimens including the height of villi, the amount of goblet cells and infiltrating mononuclear cells, and the expression of the proliferative Ki-67 antigen. Changes in the lipid peroxidation in the blood and the intestine were determined by severalfold increase of the concentration of malonic dialdehyde. Oral administration of L. brevis 47 f strain prior to 5 FU decreased the drug-induced morphological and biochemical changes to their respective physiological levels; the ability of intestinal epitheliocytes to express Ki-67 was partially restored. These effects of L. brevis 47 f strain were...
Two fragments of conjugative plasmid p19 (95 kb) from the Bacillus subtilis 19 soil strain were c... more Two fragments of conjugative plasmid p19 (95 kb) from the Bacillus subtilis 19 soil strain were cloned and sequenced; these fragments carry genes, products of which are indispensable for the conjugative transfer. One of the fragments 4518 bp in size carries five open reading frames and their fragments (ORF1–ORF5). The protein corresponding to ORF4 is homologous to proteins from the family VirD4. Inactivation of ORF4 and ORF1 by insertional mutagenesis caused a three-to-fivefold decrease in the frequency of plasmid p19 conjugative transfer. Another 2932-bp fragment of p19 was shown to possess a rep region homologous to the rep region of plasmid pBS72 from the B. subtilis 72 soil strain and a novel ORF (ORF6); the protein corresponding to this ORF contains the HTH motif typical for DNA-binding proteins.
Integration of expressible DNA corresponding to the human dihydrofolate reductase (hDHFR) gene in... more Integration of expressible DNA corresponding to the human dihydrofolate reductase (hDHFR) gene into the Bacillus subtilis genome has been achieved in different ways. The clones obtained contained one to seven copies of this gene per genome equivalent and were resistant to trimethoprim. Clones produce a new protein coded by the integrated hDHFR gene. In all clones, the integrated DNA was stably maintained even under nonselective growth conditions.
The properties of large plasmids harbored by Bacillus subtilis strains isolated from soils of Mos... more The properties of large plasmids harbored by Bacillus subtilis strains isolated from soils of Moscow and Moscow oblast and from different regions of the Republic of Belarus have been studied. All large plasmids in the collection of strains from Belarus were capable of conjugative mobilization of the small plasmid pUB110 and were similar in size and other properties. Most of the tested plasmids harbored by strains isolated from Moscow soils had no mobilization ability; they were of different sizes and showed no homology with the replication region of plasmids from the Belarussian collection. The uniformity of the plasmids present in strains from Belarussian soils may be due to their active horizontal transfer under natural conditions.
World Journal of Gastroenterology
Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder in which recurrent abdom... more Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder in which recurrent abdominal pain is associated with defecation or a change in bowel habits (constipation, diarrhea, or both), and it is often accompanied by symptoms of abdominal bloating and distension. IBS is an important health care issue because it negatively affects the quality of life of patients and places a considerable financial burden on health care systems. Despite extensive research, the etiology and underlying pathophysiology of IBS remain incompletely understood. Proposed mechanisms involved in its pathogenesis include increased intestinal permeability, changes in the immune system, visceral hypersensitivity, impaired gut motility, and emotional disorders. Recently, accumulating evidence has highlighted the important role of the gut microbiota in the development of IBS. Microbial dysbiosis within the gut is thought to contribute to all aspects of its multifactorial pathogenesis. The last few decades have also seen an increasing interest in the impact of antibiotics on the gut microbiota. Moreover, antibiotics have been suggested to play a role in the development of IBS. Extensive research has established that antibacterial therapy induces remarkable shifts in the bacterial community composition that are quite similar to those observed in IBS. This suggestion is further supported by data from cohort and case-control studies, indicating that antibiotic treatment is associated with an increased risk of IBS. This paper summarizes the main findings on this issue and contributes to a deeper understanding of the link between antibiotic use and the development of IBS.
PLOS ONE, 2021
Background Irritable bowel syndrome (IBS) is a pathologic condition characterized by changes in g... more Background Irritable bowel syndrome (IBS) is a pathologic condition characterized by changes in gut microbiome composition, low-grade inflammation, and disruption of intestinal wall permeability. The interaction between the gut microbiome and the disease manifestation remains unclear. The changing of tight junction proteins and cytokines expression throughout the gastrointestinal tract in IBS patients has not been studied yet. Aim of the study To assess the changes of gut microbiome composition, tight junction proteins, and cytokines expression of intestinal mucosa from the duodenum to the distal part of the colon in IBS patients and healthy volunteers. Methods In 31 IBS patients (16 patients with IBS-D; 15 patients with IBS-C) and 10 healthy volunteers the expression of CLD-2, CLD-3, CLD-5, IL-2, IL-10, and TNF-α in mucosal biopsy specimens was determined by morphological and immune-histochemical methods. The qualitative and quantitative composition of the intestinal microbiota was...
Background. Hemodynamic changes (hyperdynamic circulation) and gut dysbiosis are observed in cirr... more Background. Hemodynamic changes (hyperdynamic circulation) and gut dysbiosis are observed in cirrhosis. It was suggested that gut dysbiosis contributes to the development of hyperdynamic circulation, which aggravates the course of cirrhosis. The aim is to test this hypothesis.Methods. The cross-sectional observational study included 47 patients with cirrhosis. Stool microbiome was assessed using 16S rRNA gene sequencing. Echocardiography with a simultaneous assessment of blood pressure and heart rate was performed. Hemodynamic parameters were calculated. Results. Hyperdynamic circulation was found in 34% of patients. Patients with hyperdynamic circulation had higher incidences of clinically significant ascites (p=0.018), overt hepatic encephalopathy (p=0.042), hypoalbuminemia (p=0.011), hypoprothrombinemia (p=0.019), systemic inflammation (p=0.002), and severe hyperbilirubinemia (p=0.042) than patients without hyperdynamic circulation. The abundance of Proteobacteria (p=0.012), Ente...
Minerva Gastroenterology, 2021
Russian Journal of Gastroenterology, Hepatology, Coloproctology, 2020
Aim. The study reviews current evidence on digestive system lesions provoked by the new COVID-19 ... more Aim. The study reviews current evidence on digestive system lesions provoked by the new COVID-19 coronavirus infection.Key points. Alongside the destructive impact on respiratory system, COVID-19 manifests itself in gastrointestinal symptoms (nausea, vomiting, diarrhoea) that may precede respiratory signs and prevail in the clinical picture of infection. Patients with chronic inflammatory bowel diseases receiving immunosuppressive therapy are at elevated risk of severe COVID-19 progression. The new coronavirus infection may induce liver damage with increased transaminase activity.Conclusion. Association of digestive system lesions with COVID-19 remains understudied and requires further research.
Russian Journal of Gastroenterology, Hepatology, Coloproctology, 2020
Цель обзора. Представить причины нарушения проницаемости слизисто-эпителиального барьера и рассмо... more Цель обзора. Представить причины нарушения проницаемости слизисто-эпителиального барьера и рассмотреть их как патогенетический фактор развития функциональных заболеваний желудочно-кишечного тракта (ЖКТ). Основные положения. Слизисто-эпителиальный барьер ЖКТ включает в себя несколько компонентов: преэпителиальная защита-слой слизи, покрывающей эпителий; эпителиальная защита, к которой относится высокая регенерация эпителия и плотные межклеточные контакты; постэпителиальная защита-клетки иммунной системы и кровеносные сосуды. Состав кишечной микробиоты также может рассматриваться как часть слизисто-эпителиального барьера. У пациентов с функциональной диспепсией (ФД) и синдромом раздраженного кишечника (СРК) определяется ряд морфологических изменений. Так, у пациентов с ФД выявлено изменение экспрессии белков, образующих межэпителиальные контакты (клаудин-1, zonula occludens, окклюдин, Е-кадгерин, β-катенин и десмоглин-2), а у пациентов с СРК-повышенная экспрессия клаудина-2. Нарушение проницаемости приводит к развитию воспалительных изменений в кишечной стенке, в результате которых формируются висцеральная и центральная сенситизация, а также нарушение моторики кишечника, что, в свою очередь, приводит к развитию симптомов СРК и ФД. Заключение: нарушение барьерной функции слизисто-эпителиального слоя ЖКТ может рассматриваться как один из патогенетических факторов развития ФД и СРК. Ключевые слова: синдром раздраженного кишечника, функциональная диспепсия, слизисто-эпителиальный барьер, кишечная проницаемость Конфликт интересов: авторы заявляют об отсутствии конфликта интересов. Для цитирования: Ковалева А.Л., Полуэктова Е.А., Шифрин О.С. Кишечный барьер, кишечная проницаемость, неспецифическое воспаление и их роль в формировании функциональных заболеваний желудочно-кишечного тракта. Российской гастроэнтерологической ассоциации по диагностике и лечению гастроэзофагеальной рефлюксной болезни.
Applied Biochemistry and Microbiology, 2019
A simple HPLC technique for the quantitative determination of phytotoxins (stagonolide A and herb... more A simple HPLC technique for the quantitative determination of phytotoxins (stagonolide A and herbarumin I) in liquid culture of the fungus Stagonospora cirsii S-47 has been developed. Some examples of its application are given. The technique was tested in a study of effects of the concentration of refined sunflower oil and the cultivation duration on the production level of these toxins. At an oil concentration of 0.5% or higher in modified Czapek medium with vitamins, the accumulation of S. cirsii biomass and the concentration of stagonolide A increased, while the concentration of herbarumin I decreased. Maximal amounts of both phytotoxins were obtained on the tenth day of submerged S. cirsii cultivation in flasks. When S. cirsii was grown in the same medium supplied with 1% of oil in a laboratory bioreactor, the maximal concentration of stagonolide A (116 mg/L) in the liquid culture was achieved after 5 days of fermentation followed by its considerable reduction after 6 days, while after 7 days of the submerged growth the maximal content of herbarumin I (116 mg/L) increased sharply. The technique of the phytotoxins analysis was used to monitor them during their isolation, as well as for preparative HPLC.
Ontogenez
When rearing the D. virilis larvae on the nutrient medium with 5-bromodeoxyuridine-6-3H (3H-BDU) ... more When rearing the D. virilis larvae on the nutrient medium with 5-bromodeoxyuridine-6-3H (3H-BDU) at different developmental stages, it was found that the intensity of isotope incorporation in the chromosomes and cytoplasm of the salivary gland cells depended on the duration of effect and concentration. The distribution of label along the chromosomes does not occur at random. The spectrum of isotope incorporation is specific for each chromosome. All regions which changed their puffing pattern as a result of rearing the larvae on the medium with 3H-BDU incorporated the isotope and the frequency of incorporation in the most of them differed reliably from the random one. The intensity of incorporation increased with the duration of labelling and the isotope concentration.
Genetika, 1977
The expressivity and temporal patterns of function of the various puff groups are changed, when l... more The expressivity and temporal patterns of function of the various puff groups are changed, when larvae of Drosophila virilis are kept on BUdR containing medium during different periods of their larval development, as compared with the control animals kept on BUdR-free media. The magnitude of the effect depends on the stage at which the treatment is conducted; the larvae of the 3rd instar are more sensitive to BUdR. The effect of BUdR becomes considerably lower by the end of the 3rd instar period.
Power Technology and Engineering, 2011
A method of estimating the effect of the modes of operation of the automatic secondary frequency ... more A method of estimating the effect of the modes of operation of the automatic secondary frequency and power regulation and of the normalized primary frequency regulation on the efficiency of the boiler and the consumption of electric power for individual needs is proposed. The increase in the operating costs of a thermal power station due to the participation of the power units participating in the frequency and power regulation is given.
Applied Biochemistry and Microbiology
The global probiotics industry has been undergoing major changes in recent years. Approaches to f... more The global probiotics industry has been undergoing major changes in recent years. Approaches to finding and creating new probiotics, as well as a paradigm of their use in food, medicine, and pharmacology are changing. The catalyst proved to be the increasing popularity and availability of omics technologies, in particular, metagenomic studies of human and animal microbiomes. However, the efficiency and safety of drugs based on probiotic strains, as well as their marketing rates, largely depend on the levels of legal and technical regulation in the field. The present review discusses the aspects of legal regulation in Russia, the European Union and the United States, along with the advantages and disadvantages of probiotics and postbiotics. A consensus is emerging that postbiotics have a number of advantages over classical live probiotic cultures. The review also focuses on the lactobacilli family, which includes the largest number of probiotic strains studied so far and still holds a leading position among probiotics. On the legislative front, Russia is often ahead of its time with adopting such laws as the Federal Law No. 492-FZ on biosecurity, which defined the concept of human and animal microbiota and set forth legislative guidelines for its preservation. The new field of research referred to as microbiome nutrigenomics aims to achieve this goal.
BMC Microbiology, 2019
Background: All living organisms experience physiological changes regulated by endogenous circadi... more Background: All living organisms experience physiological changes regulated by endogenous circadian rhythms. The main factor controlling the circadian clock is the duration of daylight. The aim of this research was to identify the impact of various lighting conditions on physiological parameters and gut microbiota composition in rats. 3 groups of outbred rats were subjected to normal light-dark cycles, darkness and constant lighting. Results: After 1 and 3 months we studied urinary catecholamine levels in rats; indicators of lipid peroxidation and antioxidant activity in the blood; protein levels of BMAL1, CLOCK and THRA in the hypothalamus; composition and functional activity of the gut microbiota. Subjecting the rats to conditions promoting desynchronosis for 3 months caused disruptions in homeostasis. Conclusions: Changing the lighting conditions led to changes in almost all the physiological parameters that we studied. Catecholamines can be regarded as a synchronization super system of split-level circadian oscillators. We established a correlation between hypothalamic levels of Bmal1 and urinary catecholamine concentrations. The magnitude of changes in the GM taxonomic composition was different for LL/LD and DD/LD but the direction of these changes was similar. As for the predicted functional properties of the GM which characterize its metabolic activity, they didn't change as dramatically as the taxonomic composition. All differences may be viewed as a compensatory reaction to new environmental conditions and the organism has adapted to those conditions.
World journal of microbiology & biotechnology, Jan 17, 2018
Oxidative stress cause serious damages in human organism resulting in multiple diseases. Antioxid... more Oxidative stress cause serious damages in human organism resulting in multiple diseases. Antioxidant therapy includes diet, the use of chemical agents or commensal bacteria such as lactobacilli. This study aims to evaluate the antioxidant (AO) activity of cell-free culture supernatants of lactobacilli, isolated from different parts of the human body. A test system based on Escherichia coli MG1655 strains carrying plasmids encoding luminescent biosensors pSoxS-lux and pKatG-lux inducible by superoxide anion and hydrogen peroxide, respectively, was used to analyze cell-free culture supernatants of lactobacilli. Bioluminescent detection systems are suitable for quick screening of AO activity of lactobacilli. The majority of strains (51 out of 81) belonging to six different species demonstrated various levels of antioxidant activity. This activity was confirmed using the trolox equivalent method. The genome of one of the strains showing high AO activity was sequenced, and the genes puta...
Journal of basic microbiology, 2015
Lactobacilli are important microorganisms in various activities, for example, diary products, mea... more Lactobacilli are important microorganisms in various activities, for example, diary products, meat ripening, bread and pickles, but, moreover, are associated directly with human skin and cavities (e.g., mouth, gut, or vagina). Some of them are used as probiotics. Therefore, the molecular biological investigation of these bacteria is important. Earlier we described several toxin antitoxin systems (type II) in lactobacilli. Here, we describe the structure and transcriptional regulation of genes, encoding TA system YefM-YoeBLrh in three strains of Lactobacillus rhamnosus comparing stationary and exponential growth phases, the influence of stress factors and mRNA stability. The same TA system is responding to physiological and stress conditions differently in related strains. Using primer extension and RLM-RACE methods we determined three transcription start sites of RNAs in the operon. The promoter region of the operon is preceded by a conserved BOX element occurring at multiple positi...
PeerJ, 2019
Recent research has indicated that in addition to the unique genotype each individual may also ha... more Recent research has indicated that in addition to the unique genotype each individual may also have a unique microbiota composition. Difference in microbiota composition may emerge from both its species and strain constituents. It is important to know the precise composition especially for the gut microbiota (GM), since it can contribute to the health assessment, personalized treatment, and disease prevention for individuals and groups (cohorts). The existing methods for species and strain composition in microbiota are not always precise and usually not so easy to use. Probiotic bacteria of the genus Bifidobacterium and Lactobacillus make an essential component of human GM. Previously we have shown that in certain Bifidobacterium and Lactobacillus species the RelBE and MazEF superfamily of toxin-antitoxin (TA) systems may be used as functional biomarkers to differentiate these groups of bacteria at the species and strain levels. We have composed a database of TA genes of these super...
Microorganisms, 2020
We report that the results of our study indicate that Lactobacillus brevis 47 f strain isolated f... more We report that the results of our study indicate that Lactobacillus brevis 47 f strain isolated from the faeces of a healthy individual prevents the manifestations of experimental mucositis induced by treatment of Balb/c mice with the anticancer drug 5-fluorouracil (5 FU; 100 mg/kg i.p. × 3 days). The presence of damage to the intestine and the colon was determined by a morphometric analysis of specimens including the height of villi, the amount of goblet cells and infiltrating mononuclear cells, and the expression of the proliferative Ki-67 antigen. Changes in the lipid peroxidation in the blood and the intestine were determined by severalfold increase of the concentration of malonic dialdehyde. Oral administration of L. brevis 47 f strain prior to 5 FU decreased the drug-induced morphological and biochemical changes to their respective physiological levels; the ability of intestinal epitheliocytes to express Ki-67 was partially restored. These effects of L. brevis 47 f strain were...
Two fragments of conjugative plasmid p19 (95 kb) from the Bacillus subtilis 19 soil strain were c... more Two fragments of conjugative plasmid p19 (95 kb) from the Bacillus subtilis 19 soil strain were cloned and sequenced; these fragments carry genes, products of which are indispensable for the conjugative transfer. One of the fragments 4518 bp in size carries five open reading frames and their fragments (ORF1–ORF5). The protein corresponding to ORF4 is homologous to proteins from the family VirD4. Inactivation of ORF4 and ORF1 by insertional mutagenesis caused a three-to-fivefold decrease in the frequency of plasmid p19 conjugative transfer. Another 2932-bp fragment of p19 was shown to possess a rep region homologous to the rep region of plasmid pBS72 from the B. subtilis 72 soil strain and a novel ORF (ORF6); the protein corresponding to this ORF contains the HTH motif typical for DNA-binding proteins.
Integration of expressible DNA corresponding to the human dihydrofolate reductase (hDHFR) gene in... more Integration of expressible DNA corresponding to the human dihydrofolate reductase (hDHFR) gene into the Bacillus subtilis genome has been achieved in different ways. The clones obtained contained one to seven copies of this gene per genome equivalent and were resistant to trimethoprim. Clones produce a new protein coded by the integrated hDHFR gene. In all clones, the integrated DNA was stably maintained even under nonselective growth conditions.
The properties of large plasmids harbored by Bacillus subtilis strains isolated from soils of Mos... more The properties of large plasmids harbored by Bacillus subtilis strains isolated from soils of Moscow and Moscow oblast and from different regions of the Republic of Belarus have been studied. All large plasmids in the collection of strains from Belarus were capable of conjugative mobilization of the small plasmid pUB110 and were similar in size and other properties. Most of the tested plasmids harbored by strains isolated from Moscow soils had no mobilization ability; they were of different sizes and showed no homology with the replication region of plasmids from the Belarussian collection. The uniformity of the plasmids present in strains from Belarussian soils may be due to their active horizontal transfer under natural conditions.