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Authors = Roman Kozlov ORCID = 0000-0002-4881-4332

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11 pages, 920 KiB  
Systematic Review
Effect of Saccharomyces boulardii on Liver Diseases: A Systematic Review
by Roman Maslennikov, Nona Benuni, Anna Levshina, Farida Adzhieva, Tatyana Demina, Alina Kucher, Ekaterina Pervushova, Evgeniya Yuryeva, Elena Poluektova, Oxana Zolnikova, Evgenii Kozlov, Alexey Sigidaev and Vladimir Ivashkin
Microorganisms 2024, 12(8), 1678; https://doi.org/10.3390/microorganisms12081678 - 15 Aug 2024
Viewed by 3165
Abstract
We aimed to systematize the results of published studies on the use of Saccharomyces boulardii (SB) for the treatment of various liver disorders (CRD42022378050). Searches were conducted using PubMed and Scopus on 1 August 2022. The PubMed search was updated on 15 June [...] Read more.
We aimed to systematize the results of published studies on the use of Saccharomyces boulardii (SB) for the treatment of various liver disorders (CRD42022378050). Searches were conducted using PubMed and Scopus on 1 August 2022. The PubMed search was updated on 15 June 2024. The review included sixteen studies: ten experimental animal studies (EASs) and six randomized controlled trials (RCTs). The CNCM I-745 strain was used in 68.8% of the included studies. SB reduced the severity of many manifestations of cirrhosis, and lowered the Child–Pugh scores in RCT. SB reduced the serum concentrations of TNF-α, IL-1β, IL-6, and IL-4 in animals with metabolic dysfunction-associated steatotic liver disease (MASLD); lowered the serum TNF-α and IL-6 levels in experimental cirrhosis in rats; and reduced the CRP levels in decompensated cirrhosis. The EAS of MASLD revealed that SB reduced liver steatosis and inflammation and lowered the liver expression of genes of TNF-α, IL-1β, interferon-γ, and IL-10. In studies on experimental cirrhosis and MASLD, SB reduced the liver expression of genes of TGF-β, α-SMA, and collagen as well as liver fibrosis. SB reduced the abundance of Escherichia (Proteobacteria), increased the abundance of Bacteroidetes in the gut microbiota, prevented an increase in intestinal barrier permeability, and reduced bacterial translocation and endotoxemia. Full article
(This article belongs to the Special Issue Probiotics, Prebiotics, and Gut Microbes)
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16 pages, 9164 KiB  
Article
Regularities of Changes in the Structure of Different Phases of Deformed Zirconium Alloys as a Result of Raising the Annealing Temperature According to Texture Analysis Data
by Margarita Isaenkova, Olga Krymskaya, Kristina Klyukova, Anastasya Bogomolova, Ilya Kozlov, Pavel Dzhumaev, Vladimir Fesenko and Roman Svetogorov
Metals 2023, 13(10), 1784; https://doi.org/10.3390/met13101784 - 21 Oct 2023
Cited by 6 | Viewed by 1450
Abstract
Based on the data of synchrotron and electron microscopic studies of deformed and annealed Russian zirconium alloys, the possibility of analyzing the structural-phase state and crystallographic texture of individual phases has been demonstrated. A qualitative and quantitative phase analysis of deformed and annealed [...] Read more.
Based on the data of synchrotron and electron microscopic studies of deformed and annealed Russian zirconium alloys, the possibility of analyzing the structural-phase state and crystallographic texture of individual phases has been demonstrated. A qualitative and quantitative phase analysis of deformed and annealed tubes made of Zr-Nb-(Sn-Fe-O) alloys was carried out using diffraction patterns obtained with synchrotron radiation. The main α-Zr phase and the following additional phases: β-Nb, β-Zr, and the Laves phase (intermetallic compound Zr(Nb,Fe)2), were found in the alloys. According to the results of texture analysis of all phases present in the alloy, the mechanisms of plastic deformation, recrystallization, and phase transformations of the main and additional phases were established. It is shown that during plastic deformation of the Zr-1%Nb alloy, a dynamic phase transformation β-Nb→α-Zr→β-Zr is observed. It is established that during recrystallization, larger grains of α-Zr are misoriented relative to the deformed matrix by rotating the prismatic axes around the basal axes by 30°, while fine grains are improved by polygonization and maintain the orientation of the deformed matrix. Processes for changing the orientation of grains of additional phases as a result of high-temperature annealing are also considered. Full article
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16 pages, 2643 KiB  
Article
Gut Dysbiosis and Hemodynamic Changes as Links of the Pathogenesis of Complications of Cirrhosis
by Irina Efremova, Roman Maslennikov, Elena Poluektova, Maria Zharkova, Anna Kudryavtseva, George Krasnov, Maria Fedorova, Elena Shirokova, Evgenii Kozlov, Anna Levshina and Vladimir Ivashkin
Microorganisms 2023, 11(9), 2202; https://doi.org/10.3390/microorganisms11092202 - 31 Aug 2023
Cited by 6 | Viewed by 2175
Abstract
The aim was to evaluate the relationship between gut dysbiosis and hemodynamic changes (hyperdynamic circulation) in cirrhosis, and between hemodynamic changes and complications of this disease. This study included 47 patients with cirrhosis. Stool microbiome was assessed using 16S rRNA gene sequencing. Echocardiography [...] Read more.
The aim was to evaluate the relationship between gut dysbiosis and hemodynamic changes (hyperdynamic circulation) in cirrhosis, and between hemodynamic changes and complications of this disease. This 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 to assess systemic hemodynamics. Patients with hyperdynamic circulation had more severe cirrhosis, lower albumin, sodium and prothrombin levels, higher C-reactive protein, aspartate aminotransferase and total bilirubin levels, and higher incidences of portopulmonary hypertension, ascites, overt hepatic encephalopathy, hypoalbuminemia, hypoprothrombinemia, systemic inflammation, and severe hyperbilirubinemia than patients with normodynamic circulation. Patients with hyperdynamic circulation compared with those with normodynamic circulation had increased abundance of Proteobacteria, Enterobacteriaceae, Bacilli, Streptococcaceae, Lactobacillaceae, Fusobacteria, Micrococcaceae, Intestinobacter, Clostridium sensu stricto, Proteus and Rumicoccus, and decreased abundance of Bacteroidetes, Bacteroidaceae, Holdemanella, and Butyrivibrio. The systemic vascular resistance and cardiac output values correlated with the abundance of Proteobacteria, Enterobacteriaceae, Bacilli, Streptococcaceae, Lactobacillaceae, Micrococcaceae, and Fusobacteria. Heart rate and cardiac output value were negatively correlated with the abundance of Bacteroidetes. The mean pulmonary artery pressure value was positively correlated with the abundance of Proteobacteria and Micrococcaceae, and negatively with the abundance of Holdemanella. Full article
(This article belongs to the Special Issue The Interplay between Microbiota and Human Complex Traits)
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15 pages, 1628 KiB  
Article
Acinetobacter Non-baumannii Species: Occurrence in Infections in Hospitalized Patients, Identification, and Antibiotic Resistance
by Eugene Sheck, Andrey Romanov, Valeria Shapovalova, Elvira Shaidullina, Alexey Martinovich, Natali Ivanchik, Anna Mikotina, Elena Skleenova, Vladimir Oloviannikov, Ilya Azizov, Vera Vityazeva, Alyona Lavrinenko, Roman Kozlov and Mikhail Edelstein
Antibiotics 2023, 12(8), 1301; https://doi.org/10.3390/antibiotics12081301 - 9 Aug 2023
Cited by 16 | Viewed by 4891
Abstract
Background: Acinetobacter species other than A. baumannii are becoming increasingly more important as opportunistic pathogens for humans. The primary aim of this study was to assess the prevalence, species distribution, antimicrobial resistance patterns, and carbapenemase gene content of clinical Acinetobacter non-baumannii ( [...] Read more.
Background: Acinetobacter species other than A. baumannii are becoming increasingly more important as opportunistic pathogens for humans. The primary aim of this study was to assess the prevalence, species distribution, antimicrobial resistance patterns, and carbapenemase gene content of clinical Acinetobacter non-baumannii (Anb) isolates that were collected as part of a sentinel surveillance program of bacterial infections in hospitalized patients. The secondary aim was to evaluate the performance of MALDI-TOF MS systems for the species-level identification of Anb isolates. Methods: Clinical bacterial isolates were collected from multiple sites across Russia and Kazakhstan in 2016–2022. Species identification was performed by means of MALDI-TOF MS, with the Autobio and Bruker systems used in parallel. The PCR detection of the species-specific blaOXA-51-like gene was used as a means of differentiating A. baumannii from Anb species, and the partial sequencing of the rpoB gene was used as a reference method for Anb species identification. The susceptibility of isolates to antibiotics (amikacin, cefepime, ciprofloxacin, colistin, gentamicin, imipenem, meropenem, sulbactam, tigecycline, tobramycin, and trimethoprim–sulfamethoxazole) was determined using the broth microdilution method. The presence of the most common in Acinetobacter-acquired carbapenemase genes (blaOXA-23-like, blaOXA-24/40-like, blaOXA-58-like, blaNDM, blaIMP, and blaVIM) was assessed using real-time PCR. Results: In total, 234 isolates were identified as belonging to 14 Anb species. These comprised 6.2% of Acinetobacter spp. and 0.7% of all bacterial isolates from the observations. Among the Anb species, the most abundant were A. pittii (42.7%), A. nosocomialis (13.7%), the A. calcoaceticus/oleivorans group (9.0%), A. bereziniae (7.7%), and A. geminorum (6.0%). Notably, two environmental species, A. oleivorans and A. courvalinii, were found for the first time in the clinical samples of patients with urinary tract infections. The prevalence of resistance to different antibiotics in Anb species varied from <4% (meropenem and colistin) to 11.2% (gentamicin). Most isolates were susceptible to all antibiotics; however, sporadic isolates of A. bereziniae, A. johnsonii, A. nosocomialis, A. oleivorans, A. pittii, and A. ursingii were resistant to carbapenems. A. bereziniae was more frequently resistant to sulbactam, aminoglycosides, trimethoprim–sulfamethoxazole, and tigecycline than the other species. Four (1.7%) isolates of A. bereziniae, A. johnsonii, A. pittii were found to carry carbapenemase genes (blaOXA-58-like and blaNDM, either alone or in combination). The overall accuracy rates of the species-level identification of Anb isolates with the Autobio and Bruker systems were 80.8% and 88.5%, with misidentifications occurring in 5 and 3 species, respectively. Conclusions: This study provides important new insights into the methods of identification, occurrence, species distribution, and antibiotic resistance traits of clinical Anb isolates. Full article
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16 pages, 2081 KiB  
Article
Laser Ablation-Generated Crystalline Selenium Nanoparticles Prevent Damage of DNA and Proteins Induced by Reactive Oxygen Species and Protect Mice against Injuries Caused by Radiation-Induced Oxidative Stress
by Sergey V. Gudkov, Meng Gao, Alexander V. Simakin, Alexey S. Baryshev, Roman V. Pobedonostsev, Ilya V. Baimler, Maksim B. Rebezov, Ruslan M. Sarimov, Maxim E. Astashev, Anastasia O. Dikovskaya, Elena A. Molkova, Valery A. Kozlov, Nikolay F. Bunkin, Mikhail A. Sevostyanov, Alexey G. Kolmakov, Mikhail A. Kaplan, Mars G. Sharapov, Vladimir E. Ivanov, Vadim I. Bruskov, Valery P. Kalinichenko, Kuder O. Aiyyzhy, Valery V. Voronov, Nuttaporn Pimpha, Ruibin Li and Georgy A. Shafeevadd Show full author list remove Hide full author list
Materials 2023, 16(14), 5164; https://doi.org/10.3390/ma16145164 - 22 Jul 2023
Cited by 8 | Viewed by 1997
Abstract
With the help of laser ablation, a technology for obtaining nanosized crystalline selenium particles (SeNPs) has been created. The SeNPs do not exhibit significant toxic properties, in contrast to molecular selenium compounds. The administration of SeNPs can significantly increase the viabilities of SH-SY5Y [...] Read more.
With the help of laser ablation, a technology for obtaining nanosized crystalline selenium particles (SeNPs) has been created. The SeNPs do not exhibit significant toxic properties, in contrast to molecular selenium compounds. The administration of SeNPs can significantly increase the viabilities of SH-SY5Y and PCMF cells after radiation exposure. The introduction of such nanoparticles into the animal body protects proteins and DNA from radiation-induced damage. The number of chromosomal breaks and oxidized proteins decreases in irradiated mice treated with SeNPs. Using hematological tests, it was found that a decrease in radiation-induced leukopenia and thrombocytopenia is observed when selenium nanoparticles are injected into mice before exposure to ionizing radiation. The administration of SeNPs to animals 5 h before radiation exposure in sublethal and lethal doses significantly increases their survival rate. The modification dose factor for animal survival was 1.2. It has been shown that the introduction of selenium nanoparticles significantly normalizes gene expression in the cells of the red bone marrow of mice after exposure to ionizing radiation. Thus, it has been demonstrated that SeNPs are a new gene-protective and radioprotective agent that can significantly reduce the harmful effects of ionizing radiation. Full article
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13 pages, 1448 KiB  
Article
Assessment of Antimicrobial Consumption in Multi-Field Hospitals with Pediatric Inpatients: Conventional vs. Novel Pediatric-Adjusted Methodologies
by Svetlana Rachina, Yuliya Belkova, Roman Kozlov, Vladimir Mladov, Vladimir Mishchenko, Alla Andreeva, Olga Domanskaya, Ulyana Portnjagina, Anastasiia Dushina and Khadizhat Zainalabidova
Antibiotics 2023, 12(7), 1162; https://doi.org/10.3390/antibiotics12071162 - 7 Jul 2023
Viewed by 1588
Abstract
Background: the objective of this study was to propose a methodology for the assessment of antimicrobial consumption (AMC) in pediatric inpatients and to estimate variances in consumption levels in multi-field hospitals with pediatric inpatients, calculated by means of the pediatric-adjusted methodology vs. the [...] Read more.
Background: the objective of this study was to propose a methodology for the assessment of antimicrobial consumption (AMC) in pediatric inpatients and to estimate variances in consumption levels in multi-field hospitals with pediatric inpatients, calculated by means of the pediatric-adjusted methodology vs. the conventional methodology. Methods: the pediatric-adjusted methodology based on the conventional ATC/DDD method and children’s DDDs (cDDD) for antimicrobials were proposed and validated in a series of probabilistic sensitivity analyses of real clinical data extracted from the receipt notes of three multi-field hospitals. Differences in AMC in multi-field hospitals with pediatric inpatients, calculated by means of the proposed methodology vs. the conventional methodology, were assessed for a virtual cohort of inpatients, with the pediatric share increasing by 1%. Results: in children ≤12 years old, assessment by the standard methodology resulted in a 59% underestimation of AMC from the levels based on prescribed doses, vs. a 25% underestimation for the proposed methodology. In a mixed-age virtual population of inpatients, the underestimation of consumption levels rose to 321% for the ATC/DDD methodology compared to the proposed one. Conclusions: the proposed methodology demonstrated a higher accuracy of AMC estimates compared to the conventional one and can be considered for the quantification of antimicrobial utilization in pediatric institutions and multi-field hospitals with a substantial share of pediatric inpatients. Full article
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15 pages, 2961 KiB  
Article
3′UTR of mRNA Encoding CPEB Protein Orb2 Plays an Essential Role in Intracellular Transport in Neurons
by Eugene N. Kozlov, Roman V. Deev, Elena V. Tokmatcheva, Anna Tvorogova, Zaur M. Kachaev, Rudolf A. Gilmutdinov, Mariya Zhukova, Elena V. Savvateeva-Popova, Paul Schedl and Yulii V. Shidlovskii
Cells 2023, 12(13), 1717; https://doi.org/10.3390/cells12131717 - 25 Jun 2023
Cited by 1 | Viewed by 2223
Abstract
Intracellular trafficking plays a critical role in the functioning of highly polarized cells, such as neurons. Transport of mRNAs, proteins, and other molecules to synaptic terminals maintains contact between neurons and ensures the transmission of nerve impulses. Cytoplasmic polyadenylation element binding (CPEB) proteins [...] Read more.
Intracellular trafficking plays a critical role in the functioning of highly polarized cells, such as neurons. Transport of mRNAs, proteins, and other molecules to synaptic terminals maintains contact between neurons and ensures the transmission of nerve impulses. Cytoplasmic polyadenylation element binding (CPEB) proteins play an essential role in long-term memory (LTM) formation by regulating local translation in synapses. Here, we show that the 3′UTR of the Drosophila CPEB gene orb2 is required for targeting the orb2 mRNA and protein to synapses and that this localization is important for LTM formation. When the orb2 3′UTR is deleted, the orb2 mRNAs and proteins fail to localize in synaptic fractions, and pronounced LTM deficits arise. We found that the phenotypic effects of the orb2 3′UTR deletion were rescued by introducing the 3′UTR from the orb, another Drosophila CPEB gene. In contrast, the phenotypic effects of the 3′UTR deletion were not rescued by the 3′UTR from one of the Drosophila α-tubulin genes. Our results show that the orb2 mRNAs must be targeted to the correct locations in neurons and that proper targeting depends upon sequences in the 3′UTR. Full article
(This article belongs to the Section Cells of the Nervous System)
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22 pages, 26818 KiB  
Article
Production of Workpieces from Martensitic Stainless Steel Using Electron-Beam Surfacing and Investigation of Cutting Forces When Milling Workpieces
by Nikita V. Martyushev, Victor N. Kozlov, Mengxu Qi, Vadim S. Tynchenko, Roman V. Kononenko, Vladimir Yu. Konyukhov and Denis V. Valuev
Materials 2023, 16(13), 4529; https://doi.org/10.3390/ma16134529 - 22 Jun 2023
Cited by 37 | Viewed by 2019
Abstract
The aim of this study was to investigate cutting force when milling 40 × 13 stainless steel samples obtained via electron-beam surfacing. The samples were obtained by surfacing the wire made from the martensitic 40 × 13 stainless steel. The microstructure of the [...] Read more.
The aim of this study was to investigate cutting force when milling 40 × 13 stainless steel samples obtained via electron-beam surfacing. The samples were obtained by surfacing the wire made from the martensitic 40 × 13 stainless steel. The microstructure of the samples and the hardness are discussed in the present study. Emphasis is placed on the study of cutting forces when handling the samples. The structure of the samples obtained by electron-beam surfacing consisted of tempered martensite. The average hardness of the samples was similar to the hardness obtained after quenching and tempering the samples—576 HV for horizontally printed workpieces and 525 HV for vertically printed workpieces. High-speed milling, high-efficiency milling, and conventional milling have been proven to be suitable for handling such workpieces. This study shows that an increase in milling width leads to a gradual decrease in specific cutting force. As the milling depth increases, the specific cutting force decreases intensively at first but then more slowly with time. Machining the workpieces made of the martensitic stainless steel and produced by electron-beam surfacing requires the use of purely carbide mills with a diameter of at least 12 mm. Using a high-speed steel as a tool material results in the rapid failure of the tool. The cutting conditions during the investigation allowed for a decrease in the temperature of the cutting edge, cutting force, and the low-rigid end mill bending. Therefore, this study has made it possible to select modes that allow for a reduction in the vibration of the lathe-fixture-tool-part system. Full article
(This article belongs to the Special Issue Advances in Materials Processing Engineering)
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24 pages, 7254 KiB  
Article
The Keivy Domain of the Kola Granulite–Gneiss Area on the Baltic Shield: Most Ancient Median Massif of the Continental Crust
by Nickolay Sorokhtin, Nikolay Kozlov, Igor Semiletov, Leopold Lobkovsky, Sergey Nikiforov, Dmitry Alekseev and Roman Ananiev
Geosciences 2023, 13(5), 142; https://doi.org/10.3390/geosciences13050142 - 12 May 2023
Viewed by 2142
Abstract
Studies of lithotectonic formations within the Keivy domain of the NE Baltic Shield have shown that the domain was tectonically overlapped by adjacent microcontinents during regional collision processes in the Late Archean. As a consequence, the continental crust of the Keivy domain was [...] Read more.
Studies of lithotectonic formations within the Keivy domain of the NE Baltic Shield have shown that the domain was tectonically overlapped by adjacent microcontinents during regional collision processes in the Late Archean. As a consequence, the continental crust of the Keivy domain was submerged, relative to other blocks of the continental crust, and the described domain acquired the features of a classical median massif. Surrounded on all sides by collision systems, the Keivy median massif entered the cratonization regime. This led to intensive processes of denudation of the surrounding domains of the crust and the accumulation of a thick sedimentary cover on the surface. The described processes occurred during the formation of the first supercontinent (Monogea) in the history of the Earth and the manifestation of the Early Precambrian Huronian glaciation, which left its traces on most domains of the Earth’s continental crust. Thus, the processes of peneplain formation within the Keivy massif occurred under the cold weather conditions, high volcanic activity in the peripheral zones, and sedimentary cover saturation with the products of the physical and chemical mineral transformation of tonalite–trondhjemite and greenstone rock assemblages. The unique combination of certain geodynamic and climatic cycles on the Baltic Shield in the Late Archean led to the accumulation of extensive stratiform deposits of alumina raw materials within the Keivy median massif. Full article
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10 pages, 492 KiB  
Article
Genetic Determinants of Macrolide and Fluoroquinolone Resistance in Mycoplasma genitalium and Their Prevalence in Moscow, Russia
by Inna Alexandrovna Edelstein, Alexandr Evgenjevich Guschin, Andrew Vyacheslavovich Romanov, Ekaterina Sergeevna Negasheva and Roman Sergeevich Kozlov
Pathogens 2023, 12(3), 496; https://doi.org/10.3390/pathogens12030496 - 22 Mar 2023
Cited by 5 | Viewed by 2317
Abstract
Macrolide (MLR) and fluoroquinolone (FQR) resistance in Mycoplasma genitalium (MG) has recently become a major problem worldwide. The available data on the prevalence of MLR and FQR in MG in Russia are limited. In this study, we aimed to evaluate the prevalence and [...] Read more.
Macrolide (MLR) and fluoroquinolone (FQR) resistance in Mycoplasma genitalium (MG) has recently become a major problem worldwide. The available data on the prevalence of MLR and FQR in MG in Russia are limited. In this study, we aimed to evaluate the prevalence and pattern of mutations in 213 MG-positive urogenital swabs from patients in Moscow between March 2021 and March 2022. MLR- and FQR-associated mutations were searched in 23S rRNA as well as in the parC and gyrA genes using Sanger sequencing. The prevalence of MLR was 55/213 (26%), with A2059G and A2058G substitutions being the two most common variants (36/55, 65%, and 19/55, 35%, respectively). FQR detection showed 17% (37/213); two major variants were D84N (20/37, 54%) and S80I (12/37, 32.4%) and three minor variants were S80N (3/37, 8.1%), D84G (1/37, 2.7%), and D84Y (1/37, 2.7%). Fifteen of the fifty-five MLR cases (27%) simultaneously harbored FQR. This study revealed the high frequency of MLR and FQR. We conclude that the improvement of patient examination algorithms and therapeutic approaches should be combined with the routine monitoring of antibiotic resistance based on the sensitivity profiles presented. Such a complex approach will be essential for restraining the development of treatment resistance in MG. Full article
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23 pages, 4288 KiB  
Article
Late Mesozoic and Cenozoic Geodynamics of the Arctic Region: Implications for Abiogenic Generation of Hydrocarbons
by Nickolay Sorokhtin, Leopold Lobkovsky, Igor Semiletov, Eduard Shipilov, Sergey Nikiforov, Nikolay Kozlov, Natalia Shakhova, Roman Ananiev and Dmitry Alekseev
Geosciences 2023, 13(3), 68; https://doi.org/10.3390/geosciences13030068 - 28 Feb 2023
Cited by 2 | Viewed by 2573
Abstract
Late Mesozoic and Cenozoic geodynamics of the Arctic region is discussed in the context of possible mechanisms which provide multistage cyclic transformations and transport of carbon through crust and mantle. Geodynamic processes control the abiogenic generation of hydrocarbons and the patterns of their [...] Read more.
Late Mesozoic and Cenozoic geodynamics of the Arctic region is discussed in the context of possible mechanisms which provide multistage cyclic transformations and transport of carbon through crust and mantle. Geodynamic processes control the abiogenic generation of hydrocarbons and the patterns of their localization. Possible mechanisms of abiotic hydrocarbon generation are explained in the context of carbon transport from subduction zones to rifts and serpentinization of ultramafic rocks in the rifts in the case of the Laptev Sea and Gakkel Ridge areas. The carbon of shallow crust origin migrates with encapsulated fragments of marine sediments which are consumed in the Pacific subduction zone where they become destroyed and transformed by different chemical and physical processes. The resulting C-species are involved in mantle convection flows and reach the continental rifts of the Laptev Sea and the Gakkel mid-ocean ridge. Thus, the hydrocarbons formed in the crust and in the mantle acquire signatures of abiotic origin. According to the authors, the scale of manifestation of abiogenic methanogenesis in the lower parts of the lithosphere and in the upper mantle is not so wide. Numerous small (mm and fractions of the mm) particles of exogenous matter and dispersed carbon pulled into the mantle can only form a stable crustal geochemical plume that propagates in the plane of movement of convective flows. Indirectly, the scale of manifestation of this process can be judged by the volumes of degassing of hydrocarbon and carbon dioxide gases, as well as hydrogen and its compounds in the rift systems of the earth’s crust, which are extremely insignificant. However, in the cold seas of the Eastern Arctic, massive emissions of bubble methane of mixed genesis were found. As shown in the literature, the range of variability of stable isotopes of carbon and 14C of methane in certain areas of discharge associated with rifting demonstrates values (anomalously heavy 13C, and young 14C) that can be considered as examples of presumably abiogenic origin. Our work is mostly theoretical and suggests further discussion and improvement of the mechanism of formation of abiogenic hydrocarbons and the processes of their transformation. Full article
(This article belongs to the Special Issue Permafrost and Gas Hydrate Response to Ground Temperature Rising)
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19 pages, 4157 KiB  
Article
Long-Term Memory Formation in Drosophila Depends on the 3′UTR of CPEB Gene orb2
by Eugene N. Kozlov, Elena V. Tokmatcheva, Anastasia M. Khrustaleva, Eugene S. Grebenshchikov, Roman V. Deev, Rudolf A. Gilmutdinov, Lyubov A. Lebedeva, Mariya Zhukova, Elena V. Savvateeva-Popova, Paul Schedl and Yulii V. Shidlovskii
Cells 2023, 12(2), 318; https://doi.org/10.3390/cells12020318 - 14 Jan 2023
Cited by 5 | Viewed by 3772
Abstract
Activation of local translation in neurites in response to stimulation is an important step in the formation of long-term memory (LTM). CPEB proteins are a family of translation factors involved in LTM formation. The Drosophila CPEB protein Orb2 plays an important role in [...] Read more.
Activation of local translation in neurites in response to stimulation is an important step in the formation of long-term memory (LTM). CPEB proteins are a family of translation factors involved in LTM formation. The Drosophila CPEB protein Orb2 plays an important role in the development and function of the nervous system. Mutations of the coding region of the orb2 gene have previously been shown to impair LTM formation. We found that a deletion of the 3’UTR of the orb2 gene similarly results in loss of LTM in Drosophila. As a result of the deletion, the content of the Orb2 protein remained the same in the neuron soma, but significantly decreased in synapses. Using RNA immunoprecipitation followed by high-throughput sequencing, we detected more than 6000 potential Orb2 mRNA targets expressed in the Drosophila brain. Importantly, deletion of the 3′UTR of orb2 mRNA also affected the localization of the Csp, Pyd, and Eya proteins, which are encoded by putative mRNA targets of Orb2. Therefore, the 3′UTR of the orb2 mRNA is important for the proper localization of Orb2 and other proteins in synapses of neurons and the brain as a whole, providing a molecular basis for LTM formation. Full article
(This article belongs to the Special Issue New Advances in Synaptic Dysfunctions and Plasticity)
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25 pages, 754 KiB  
Article
The Effect of Interest Rate Changes on Consumption: An Age-Structured Approach
by Roman Kozlov
Economies 2023, 11(1), 23; https://doi.org/10.3390/economies11010023 - 11 Jan 2023
Cited by 8 | Viewed by 41780
Abstract
Interest rates have generally trended downward over the past several decades. It has made borrowing cheaper, which has encouraged people to spend more. It has also made saving less attractive, contributing to increased consumption. At the same time, the role of household credit [...] Read more.
Interest rates have generally trended downward over the past several decades. It has made borrowing cheaper, which has encouraged people to spend more. It has also made saving less attractive, contributing to increased consumption. At the same time, the role of household credit increased significantly. The paper suggests a model for the effect of an interest rate change on household consumption, which relies on income and loans. The model is based on methods of the optimal control theory. The approach is age-structured: households reconsider their consumption patterns at the moment of the interest rate change and the changes in consumption patterns are age dependent. The consumption changes for different age groups contribute to the modification of aggregate consumption. Numerical simulation shows that a decrease in the interest rate leads to a consumption boost (a substantial increase in consumption in the short run), which diminishes as time passes and consumption becomes fully adjusted to the new interest rate value. The consumption boost is achieved by an increase in the debt load. Full article
(This article belongs to the Special Issue Consumer Economics)
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9 pages, 1105 KiB  
Article
Course of Lower Respiratory Tract Infection in Young People Treated at the Military Hospital of Smolensk Garrison with Detected Mycoplasma pneumoniae Carrying a Macrolide-Resistant Mutation in 23S rRNA Gene
by Inna Alexandrovna Edelstein, Olga Vladimirovna Ivanova, Oleg Igorevich Romashov and Roman Sergeevich Kozlov
Pathogens 2023, 12(1), 103; https://doi.org/10.3390/pathogens12010103 - 7 Jan 2023
Cited by 5 | Viewed by 2377
Abstract
We evaluated the effect of macrolide-resistant mutations in the Mycoplasma pneumoniae 23S rRNA gene on the severity of lower respiratory tract infections in immunocompetent young adults treated at the Smolensk Military Hospital between 25 October 2017, and 17 November 2021. All analyzed cases represented [...] Read more.
We evaluated the effect of macrolide-resistant mutations in the Mycoplasma pneumoniae 23S rRNA gene on the severity of lower respiratory tract infections in immunocompetent young adults treated at the Smolensk Military Hospital between 25 October 2017, and 17 November 2021. All analyzed cases represented a non-severe infection of the lower respiratory tract: 44 case histories with community-acquired pneumonia and 20 cases with acute bronchitis. The presence of mutations in the gene 23S rRNA of M. pneumoniae was determined with standard Sanger sequencing. The macrolide-resistant genotype was found in 4/44 (9.1%) of the samples of the patients with pneumonia and in 3/20 (15%) of the samples of the patients with acute bronchitis. The analyzed cases with identified M. pneumoniae carrying a mutation in the 23S rRNA gene did not show any differences in the clinical presentation in terms of disease severity caused by M. pneumoniae with the wild-type (WT) phenotype. Full article
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15 pages, 1825 KiB  
Article
Molecular Epidemiology of mcr-1-Positive Escherichia coli and Klebsiella pneumoniae Isolates: Results from Russian Sentinel Surveillance (2013–2018)
by Valeria Shapovalova, Elvira Shaidullina, Ilya Azizov, Eugene Sheck, Alexey Martinovich, Marina Dyachkova, Alina Matsvay, Yulia Savochkina, Kamil Khafizov, Roman Kozlov, German Shipulin and Mikhail Edelstein
Microorganisms 2022, 10(10), 2034; https://doi.org/10.3390/microorganisms10102034 - 14 Oct 2022
Cited by 4 | Viewed by 2709
Abstract
Background: The dissemination of mobile colistin resistance (mcr) genes is a serious healthcare threat because polymyxins represent “last-line” therapeutics for multi-drug-resistant Gram-negative pathogens. This study aimed to assess the prevalence of colistin resistance and mcr genes and characteristics of clinical Escherichia [...] Read more.
Background: The dissemination of mobile colistin resistance (mcr) genes is a serious healthcare threat because polymyxins represent “last-line” therapeutics for multi-drug-resistant Gram-negative pathogens. This study aimed to assess the prevalence of colistin resistance and mcr genes and characteristics of clinical Escherichia coli (Eco) and Klebsiella pneumoniae (Kpn) isolates and plasmids carrying these genes in Russia. Methods: A total of 4324 Eco and 4530 Kpn collected in the frame of sentinel surveillance in 2013–2018 were tested for susceptibility to colistin and other antibiotics using the broth microdilution method. mcr genes were screened by real-time PCR. Phylogeny, genomic features and plasmids of mcr-positive isolates were assessed using whole-genome sequencing and subsequent bioinformatic analysis. Results: Colistin resistance was detected in 2.24% Eco and 9.3% Kpn. Twenty-two (0.51%) Eco and two (0.04%) Kpn from distant sites carried mcr-1.1. Most mcr-positive isolates co-harbored ESBLs and other resistance determinants to various antibiotic classes. The mcr-positive Eco belonged to 16 MLST types, with ST359 being most common; Kpn belonged to ST307 and ST23. mcr-1.1 was carried mainly in IncI2 (n = 18) and IncX4 (n = 5) plasmids highly similar to those identified previously in human, animal and environmental isolates. Conclusion: This study demonstrated a dissemination of “typical” mcr-bearing plasmids among diverse Eco and Kpn genotypes and across a wide geographic area in Russia. Given the frequent association of mcr with other resistance determinants and potential clinical impact, the continual surveillance of this threat is warranted. Full article
(This article belongs to the Special Issue Antimicrobial Resistance Mechanisms in Bacteria)
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