bluuebunny/crossref_metadata_2025 huggingface dataset:
Cumulative effects of paraoxon and leptin on oxidative damages in rat tissues: prophylactic and therapeutic roles of N-acetylcysteine
Authors: Khazaie S. , Jafari M. , Golamloo M. , Asgari A. , Heydari J. , Salehi M. , Salem F.
Published: April 2024

Exposure to paraoxon (POX) and leptin (LP) could cause an imbalance between oxidants and antioxidants in an organism, which can be prevented by introduction of exogenous antioxidants such as N-acetylcysteine (NAC). The aim of this study was to evaluate synergic or additive effects of administration of exogenous LP plus POX on the antioxidant status, as well as the prophylactic and therapeutic roles of NAC in various rat tissues. Fifty-four male Wistar rats were divided into nine groups treated with different compounds: Control (no treatment), POX (0.7 mg/kg), NAC (160 mg/kg), LP (1 mg/kg), POX + LP, NAC-POX, POX-NAC, NAC-POX + LP, and POX + LP-NAC. In the last five groups, only the order of administered compounds differed. After 24 h, plasma and tissues were sampled and examined. The results showed that administration of POX plus LP significantly increased biochemical indices in plasma and antioxidant enzymes activities and decreased glutathione content in the liver, erythrocytes, brain, kidney, and heart. In addition, cholinesterase and paraoxonase 1 activities in the POX + LP-treated group were decreased and malondialdehyde level was increased in the liver, erythrocytes, and brain. However, administration of NAC rectified induced changes although not to the same extent. Our study suggests that POX or LP administration engage the oxidative stress system per se; however, their combination did not produce significantly greater effects. Moreover, both prophylactic and therapeutic treatments of rats with NAC supported the antioxidant defense against oxidative damage in tissues, most probably through both its free radical scavenging ability and maintaining intracellular GSH levels. It can therefore be suggested that NAC has particularly protective effects against POX or/and LP toxicity.
Alterations in the properties of the glutamatergic system of the rat hippocampus in a lithium-pilocarpine model of temporal lobe epilepsy
Authors: Diespirov G. P , Postnikova T. Y , Griflyuk A. V , Kovalenko A. A , Zaitsev A. V
Published: April 2024

Status epilepticus (SE) triggers many pathological changes in the nervous system that are not yet fully understood and may lead to the development of epilepsy. In this work, we studied the effects of SE on the properties of excitatory glutamatergic transmission in the hippocampus in a rat model of lithium-pilocarpine temporal lobe epilepsy. Studies were performed 1 day (acute phase of the model), 3 and 7 days (latent phase), and 30 to 80 days (chronic phase) after SE. Using real-time PCR, we found that in the latent phase there is a decrease in gene expression of GluA1 and GluA2 AMPA receptor subunits, which may also be accompanied by an increased proportion of calcium-permeable AMPA receptors, which play an essential role in the pathogenesis of many CNS diseases. In acute brain slices we found a decrease in the efficiency of excitatory synaptic neurotransmission in all phases of the model when recording field responses in the CA1 region of the hippocampus in response to stimulation of Schaffer collaterals by electric currents of different intensities. However, in the chronic phase we found an increase in the frequency of spontaneous excitatory postsynaptic potentials, indicating an increased background activity of the glutamatergic system in epilepsy. This is also supported by a decrease in the threshold of hind limb extension in the test of maximal electroshock seizure in rats with temporal lobe epilepsy compared to control animals. The results obtained indicate the presence of a number of functional alterations in the glutamatergic system related to epilepsy. These findings can be used to develop antiepileptogenic therapy.
Prospects for the use of intranasally administered insulin and insulin-like growth factor-1 in cerebral ischemia
Authors: Zorina I. I , Avrova N. F , Zakharova I. O , Shpakov A. O
Published: April 2024

Currently, the approaches used to treat stroke have significant limitations, and neuroprotective therapy is ineffective. In this regard, the search for effective neuroprotectors and the development of new neuroprotective strategies in cerebral ischemia are still relevant. Insulin and insulin-like growth factor-1 (IGF-1) play a key role in the functioning of the brain, are involved in the regulation of growth, differentiation and survival of neurons, neuronal plasticity, food intake, control peripheral metabolism and endocrine functions. They have a complex effect on the brain, including neuroprotective effects in cerebral ischemia and stroke. Experiments on animals and cell cultures have shown that insulin and IGF-1 under hypoxic conditions improve energy metabolism in neurons and glial cells, have a positive effect on blood microcirculation in the brain, restore nerve cell functions and neurotransmission processes, and have anti-inflammatory and antiapoptotic effects on brain cells. Of greatest interest to the clinic is the intranasal route of administration of insulin and IGF-1, since it allows dosed delivery of these hormones directly to the brain, bypassing the blood-brain barrier. Intranasally administered insulin demonstrates a pronounced positive effect in the correction of cognitive impairment in elderly people with neurodegenerative and metabolic disorders. Insulin and IGF-1 administered intranasally improve increase the survival of animals with ischemic stroke. The review discusses literature data and the results of our own studies on the mechanisms of the neuroprotective action of intranasally administered insulin and IGF-1 in cerebral ischemia and the prospects for their use to normalize CNS functions and reduce neurodegenerative changes in this pathology.
Presynaptic plasticity is associated with actin polymerization
Authors: Kudryashova I. V
Published: April 2024

Modifications of presynaptic short-term plasticity as a result of actin polymerization were tested in rat hippocampal slices using a paired-pulse paradigm. Paired-pulse stimulation of Schaffer collaterals with 70 ms interpulse interval was continuously presented every 30 s before and during perfusion with jasplakinolide, an activator of actin polymerization. Jasplakinolide application resulted in the potentiation of CA3-CA1 responses accompanied by paired-pulse facilitation decrease, these effects suggesting presynaptic modifications. The jasplakinolide-induced potentiation significantly depended on the initial paired-pulse facilitation values. These data indicate that jasplakinolide-mediated changes in actin polymerization may promote high probability of release. Less typical for CA3-CA1 synapses responses with very low initial paired-pulse facilitation or paired-pulse depression (close to 1 or even lower) demonstrated the potentiation of the second, but not the first amplitude in a pair, paired-pulse ratio significantly increasing from 0.8 to 1.0 in average. This may suggest a negative impact of jasplakinolide on the mechanisms underlying paired-pulse depression. Nonetheless, actin polymerization promotes potentiation, though patterns of this activation may differ depending on initial input characteristics. We conclude that in addition to increased neurotransmitter release probability other mechanisms known to suppress paired pulse facilitation may be also involved in effects of jasplakinolide.
Blood oxylipin profiles as a marker of the pathogenesis of oncological diseases
Authors: Chistyakov D. V , Kovalenko L. V , Donnikov M. Y , Sergeeva M. G
Published: April 2024

Oxylipins are signal lipids derived from polyunsaturated fatty acids (PUFAs), which are formed by polyenzymatic multi-acid pathways of danger (cyclooxygenase, lipoxygenase, epoxygenase, anandamide), as well as non-enzymatically. These PUFA transformation pathways are activated in parallel, forming a mixture of active inclusions. Although the combination of oxylipins with tumor secretions was performed a long time ago, the methods of instrumental analysis have only recently been improved, measurements of oxylipins of different classes (profiles) have been compared. The review considers approaches to obtaining the profile of oxylipins by HPLC-MS/MS. The profiles of oxylipins in samples of patients with oncological diseases (breast cancer, colorectal cancer, ovarian cancer, lung cancer, prostate cancer, liver cancer) were compared. The conclusion is made about the possible possibilities of using the profile of blood oxylipins as markers of oncological diseases. Understanding the high level of exceeding the level of PUFAs and the physiological activity of oxylipin mixtures will be accompanied by the perfection of early diagnosis and prediction of the course of tumor diseases.
Adsorption of acylhydroperoxy-derived phospholipids from biomembranes by blood plasma lipoproteins
Authors: Lankin V. Z , Tikhaze A. K , Kosach V. Y , Konovalova G. G
Published: April 2024

It has been established that acylhydroperoxy derivatives of phospholipids of oxidized rat liver mitochondria during co-incubation with blood plasma lipoproteins are captured predominantly by LDL particles but not by HDL, which refutes the previously stated hypothesis about the involvement of HDL in the reverse transport of oxidized phospholipids and confirms the possibility of different mechanisms of lipohydroperoxide accumulation in LDL during oxidative stress.
Recombinant strains of oncolytic vaccinia virus for cancer immunotherapy
Authors: Shakiba Y. , Vorobyev P. O , Mahmoud M. , Hamad A. , Kochetkov D. V , Yusubalieva G. M , Baklaushev V. P , Chumakov P. M , Lipatova A. V
Published: April 2024

Cancer virotherapy is an alternative therapeutic approach based on the viruses that selectively infect and kill tumor cells. Vaccinia virus (VV) is a member of the Poxviridae family of enveloped viruses with a large linear double-stranded DNA genome. The proven safety of VV strains as well as considerable transgene capacity of the viral genome, make VV an excellent platform for creating recombinant oncolytic viruses for cancer therapy. Furthermore, various genetic modifications can increase tumor selectivity and therapeutic efficacy of VV by arming it with the immune-modulatory genes or proapoptotic molecules, boosting the host immune system, and increasing cross-priming recognition of the tumor cells by T-cells or NK cells. In this review, we summarized the data on bioengineering approaches to develop recombinant VV strains for enhanced cancer immunotherapy.
Mechanisms for the development of therapy-related leukaemia caused by topoisomerase inhibitors
Authors: Lomov N. A , Viushkov V. S , Rubtsov M. A
Published: April 2024

Leukemia is a blood cancer that originates in the blood and bone marrow. Therapy-related leukemia is a leukemia associated with prior chemotherapy. Cancer therapy with DNA-topoisomerase II inhibitors is one of the most effective among chemotherapies. However, its side effect can be the development of secondary leukemia, characterized by chromosomal rearrangements involving the AML1 or MLL gene. The set of recurrent translocations in such leukemia differs from the set of chromosomal rearrangements in other neoplasia. We review the factors that drive the translocations upon treatment of cells with DNA-topoisomerase inhibitors. Such factors primarily include the mobility of double-strand DNA ends prior to translocation and the gain of functions of the fusion proteins that are formed in the cell as a result of translocation.
Thiosulfinates: cytotoxic and antitumor activity
Authors: Kulikova V. V , Morozova E. A , Koval V. S , Solyev P. N , Demidkina T. V , Revtovich S. V
Published: April 2024

The pharmacological value of some natural compounds makes them attractive for use in oncology. Sulfur-containing thiosulfinates found in plants of the genus Allium have long been known as compounds with various therapeutic properties, including antitumor. In recent years, the effect of thiosulfinates on various stages of carcinogenesis has been actively studied. In vitro and in vivo studies have shown that thiosulfinates inhibit the proliferation of cancer cells, as well as induce apoptosis. The purpose of this review is to summarize current data on the use of natural and synthetic thiosulfinates in cancer therapy. Antitumor mechanisms and molecular targets of these promising compounds are discussed. A significant part of the review is devoted to the consideration of a new strategy for the treatment of oncological diseases - the use of the method of directed enzyme prodrug therapy with the possibility of obtaining antitumor thiosulfinates in situ.
SkQ1 improves immune status and normalises the activity of antioxidant and nadph-generating enzymes in adjuvant-induced rheumatoid arthritis in rats
Authors: Kryl'skii E. D , Popova T. N , Zhaglin D. A , Razuvaev G. A , Oleynik S. A
Published: April 2024

Rheumatoid arthritis (RA) is a severe systemic autoimmune inflammatory disease. Oxidative stress and excessive formation of mitochondrial reactive oxygen species (ROS) are now considered to be the central pathogenetic mechanisms of connective tissue component destruction and the factors responsible for a highly active inflammatory process and autoimmune response. The aim of the present work was to evaluate the effect of mitochondrial-directed antioxidant 10-(6′-plastoquinonyl)decyltriphenylphosphonium (SkQ1) on immune status, intensity of free radical-induced oxidation and functioning of antioxidant system (AOS) and NADPH-generating enzymes in rats with adjuvant-induced RA. Laboratory animals were divided into 4 groups: a control group; a group of animals with RA; animals injected intraperitoneally with SkQ1 at a dose of 1250 nmol/kg every 24 hours during the next 8 days from day 7 of RA development, and animals given SkQ1 at a dose of 625 nmol/kg according to the above scheme. Material for the study was taken on day 15 after the start of the experiment. The rate of erythrocyte sedimentation, the level of circulating immune complexes, and the concentration of immunoglobulins A, M and G were determined in rats by enzyme immunoassay. The intensity of free radical-induced oxidation was assessed by iron-induced biochemiluminescence, diene conjugate content and aconitate hydratase activity. Enzyme activity and metabolite content in animal tissues were analysed spectrophotometrically. The results of the work showed that the development of RA was associated with an increase in the indicators of immune response and intensity of free radical-induced oxidation. The development of an imbalance in AOS functioning and an increase in the activity of NADPH-generating enzymes was also observed. The administration of SkQ1 resulted in a dose-dependent change in the oxidative status indicators towards the control, which was accompanied by the normalization of the immune status parameters. It seems that the tested compound decreased the level of mitochondrial ROS, resulting in an inhibition of the inflammatory response. The consequence of these changes could be inhibition of free radical generation by immunocompetent cells and subsequent mitigation of the severity of oxidative stress in the tissues.
NAD+-dependent format dehydrogenase from the thermotolerant yeast ogataea parapolymorpha: properties and protein engineering of the n-terminal sequence
Authors: Pometun A. A , Shaposhnikov L. A , Zubanova S. A , Kovalevskii R. P , Atroshenko D. L , Pometun E. V , Savin S. S , Tishkov V. I
Published: April 2024

Previously, the gene of formate dehydrogenase (FDH, EC 1.2.1.2) from the thermotolerant methylotrophic yeast Ogataea parapolymorpha DL 1 (OpaFDH) was cloned in our laboratory. The recombinant enzyme with an additional glycine amino acid residue (OpaFDH_GK) was obtained in Escherichia coli cells in an active and soluble form with a yield of more than 1 g per liter of medium. In the present work, a detailed comparison of this enzyme with FDH from other sources was carried out. Among eukaryotic formate dehydrogenases, OpaFDH has the highest thermal stability. To elucidate the effect of the N-terminal residue on the properties of the enzyme, OpaFDH_K (identical to natural) and OpaFDH_AK variants containing an additional Ala residue at the N-terminus were also obtained. It was shown that the addition of an Ala residue to the N-terminus reduces the rate constant of thermal inactivation four times compared with the addition of a Gly residue. The addition of six more histidine residues to the N-terminus of OpaFDH_AK leads to an acceleration of purification, practically does not affect the kinetic parameters, but somewhat reduces the temperature stability, which, however, can be restored to the level of OpaFDH_AK by adding 0.5 M NaCl.
Photochemical reactions of chlorophyll tetramer in water-soluble chlorophyll-binding protein BoWSCP
Authors: Cherepanov D. A , Neverov K. V , Obukhov Yu. N , Maleeva Yu. V , Gostev F. E , Shelaev I. V , Aybush A. V , Kritsky M. S , Nadtochenko V. A
Published: April 2024

The absorption dynamics of chlorophyll a in a symmetric tetrameric complex of the water-soluble chlorophyll-binding protein BoWSCP was measured by the broadband femtosecond laser pump-probe spectroscopy within the range from 400 to 780 nm with a time resolution of 20 f-200 ps. When BoWSCP was excited in the region of the Soret band at a wavelength of 430 nm, a nonradiative intramolecular conversion S3 → S1 was observed with a characteristic time of 83 ± 9 fs. When the complex was excited in the region of the Qy band at a wavelength of 670 nm, a relaxation transition between two excitonic states of the chlorophyll dimer was observed with a time of 105 ± 10 fs. Absorption spectra of excited singlet states S1 and S3 of chlorophyll a were obtained. It has been demonstrated that the delocalization of the excited state between exciton-coupled Chl molecules in the BoWSCP tetramer changes in time and depends on the excitation energy. Upon excitation of BoWSCP, an ultrafast photochemical reaction is observed in the Soret region, apparently due to the reduction of tryptophan in the vicinity of chlorophyll.
Catalytic and electrocatalytic mechanisms of cytochromes P450 in the development of biosensors and bioreactors
Authors: Koroleva P. I , Bulko T. V , Agafonova L. E , Shumyantseva V. V
Published: April 2024

Cytochromes P450 are unique family of isozymes, discovered in all kingdoms of living species (in animals, bacteria, plants, fungi, archaea). The main functional role of the cytochromes P450 is biotransformation of exogenous and endogenous compounds. This review is highlighted problem of enchasing effectivity of electrocatalysis of cytochromes P450, enzymes that have unique capabilities both for biosensors’ design and for biotechnological application. In this review paper, we summarize main methods and modern trends based on biochemical mechanism of cytochromes P450 for development of reconstructing and electrochemical catalytic systems for practical application of these enzymes.
Relationships among development, growth, body size, reproduction, aging, and longevity - trade-offs and pace-of-life
Authors: Yuan R. , Hascup E. , Hascup K. , Bartke A.
Published: April 2024

Relationships of growth, metabolism, reproduction, and body size to the biological process of aging and longevity have been studied for decades and various unifying “theories of aging” have been proposed to account for the observed associations. In general, fast development, early sexual maturation leading to early reproductive effort, as well as production of many offspring, have been linked to shorter lifespans. The relationship of adult body size to longevity includes a remarkable contrast between the positive correlation in comparisons between different species and the negative correlation seen in comparisons of individuals within the same species. We now propose that longevity and presumably also the rate of aging are related to the “pace-of-life.” A slow pace-of-life including slow growth, late sexual maturation, and a small number of offspring, predicts slow aging and long life. The fast pace of life (rapid growth, early sexual maturation, and major reproductive effort) is associated with faster aging and shorter life, presumably due to underlying trade-offs. The proposed relationships between the pace-of-life and longevity apply to both inter- and intra-species comparisons as well as to dietary, genetic, and pharmacological interventions that extend life and to evidence for early life programming of the trajectory of aging. Although available evidence suggests the causality of at least some of these associations, much further work will be needed to verify this interpretation and to identify mechanisms that are responsible.
Actuarial aging rates in human cohorts
Authors: Gavrilov L. A , Gavrilova N. S
Published: April 2024

Aging rate is an important characteristic of human aging. Attempts to measure aging rates through the Gompertz slope parameter lead to a conclusion that actuarial aging rates were stable during the most of the 20th century, but recently demonstrate an increase over time in the majority of studied populations. These findings were made using cross-sectional mortality data rather than by the analysis of mortality of real birth cohorts. In this study we analyzed historical changes of actuarial aging rates in human cohorts. The Gompertz parameters were estimated in the age interval 50-80 years using data on one-year cohort age-specific death rates from the Human Mortality Database (HMD). Totally, data for 2,294 cohorts of men and women from 76 populations were analyzed. Changes of the Gompertz slope parameter in the studied cohorts revealed two distinct patterns for actuarial aging rate. In higher mortality Eastern European countries actuarial aging rates showed continuous decline from the 1910 to 1940 birth cohort. In lower mortality Western European countries, Australia, Canada, Japan, New Zealand, and USA actuarial aging rates declined from the 1910th to approximately 1930th cohort and then increased. Overall, in 50 out of 76 populations (68%) actuarial aging rate demonstrated decreasing pattern of change over time. Compensation effect of mortality (CEM) was tested for the first time in human cohorts and the cohort species-specific lifespan was estimated. CEM was confirmed using cohort data and human cohort species-specific lifespan estimates were similar to the estimates obtained for the cross-sectional data published earlier.
A solitary stalled 80S ribosome prevents mRNA recruitment to stress granules
Authors: Fedorovskiy A. G , Burakov A. V , Terenin I. M , Bykov D. A , Lashkevich K. A , Popenko V. I , Makarova N. E , Sorokin I. I , Sukhinina A. P
Published: April 2024

In response to stress stimuli, eukaryotic cells typically suppress protein synthesis. This leads to the mRNA release from polysomes, their condensation with RNA-binding proteins, and the formation of non-membrane-bound cytoplasmic compartments called stress granules (SGs). SGs contain 40S but generally lack 60S ribosomal subunits. It is known that cycloheximide, emetine, and anisomycin, the ribosome inhibitors which block the 80S ribosome progression along mRNA and stabilize polysomes, prevent SG assembly. Conversely, puromycin, which induces premature termination, releases mRNAs from polysomes and stimulates the formation of SGs. The same effect is caused by some translation initiation inhibitors, which lead to polysome disassembly and the accumulation of mRNAs in a form of stalled 48S preinitiation complexes. Based on these and other data, it is believed that the trigger for SG formation is the presence of mRNA with extended ribosome-free segments, which tend to form condensates in the cell. In this study, we evaluated the ability of various small-molecule translation inhibitors to block or stimulate the assembly of SGs under conditions of severe oxidative stress induced by sodium arsenite. Contrary to expectations, we found that ribosome-targeting elongation inhibitors of a specific type, that arrest solitary 80S ribosomes at the beginning of the mRNA coding regions but do not interfere with all subsequent ribosomes in completing translation and leaving the transcripts (such as harringtonine, lactimidomycin, or T-2 toxin), completely prevented the formation of arsenite-induced SGs. These observations suggest that the presence of even a single 80S ribosome on mRNA is sufficient to prevent its recruitment into SGs, and the presence of extended ribosome-free regions of mRNA is not sufficient for SG formation. We propose that mRNA entry into SGs may be mediated by specific contacts between RNA-binding proteins and those regions on 40S subunits that remain inaccessible when ribosomes are associated.
Diversity and evolution of mitochondrial translation apparatus
Authors: Baleva M. V , Piunova U. E , Chicherin I. V , Levitskii S. A , Kamenski P. A
Published: April 2024

The evolution of mitochondria proceeded independently in different eukaryotic lines, reflected in the diversity of mitochondrial genomes and mechanisms of their expression observed in different eukaryotic species. Mitochondria lost most of the genes of their bacterial ancestor, partially transferred them to the nucleus or completely eliminated. However, the mitochondria of almost all eukaryotic cells retain relatively small genomes, as well as their replication, transcription, and translation apparatuses. Dependence on the nuclear genome, features of mitochondrial transcripts, and the necessity to synthesize highly hydrophobic membrane proteins led to a number of significant changes in translation apparatus derived from the bacterial ancestor. It retained the basic structure necessary for protein synthesis but became more specialized and labile. In this review, we consider what changes take place during the initiation of mitochondrial translation, and how the evolution of mitochondria affected the functions of the main factors initiating protein biosynthesis in these organelles.
The function of the conserved “non-functional” residues in apomyoglobin is to provide and preserve the correct protein topology
Authors: Bychkova V. E , Dolgikh D. A , Balobanov V. A
Published: April 2024

In this paper the answer to O. B. Ptitsyn’s question “What is the role of conserved non-functional residues in apomyoglobin” is presented, which is based on the research results of three laboratories. The role of conserved non-functional apomyoglobin residues in formation of native topology in the molten globule state of this protein is revealed. This fact allows suggesting that the conserved non-functional residues in this protein are indispensable for fixation and maintaining main elements of the correct topology of its secondary structure in the intermediate state. The correct topology is a native element in the intermediate state of the protein.
Impact of lipid matrix composition on the activity of membranotropic enzymes galactonolactone oxidase from Trypanosoma cruzi and L-galactono-1,4-lactone dehydrogenase from Arabidopsis thaliana in the system of reverse micelles
Authors: Chudin A. A , Kudryashova E. V
Published: April 2024

The study of many membrane enzymes in an aqueous medium is difficult due to the loss of their catalytic activity, which makes it necessary to use membrane-like systems, such as reverse micelles of surfactants in nonpolar organic solvents. However, it should be taken into account that micelles are a simplified model of natural membranes, since membranes contain many different components, a significant part of which are phospholipids. In this work, we studied the impact of the main phospholipids, phosphatidylcholine (PC) and phosphatidylethanolamine (PE), on the activity of membrane enzymes using galactonolactone oxidase from Trypanosoma cruzi (TcGAL) and L-galactono-1,4-lactone dehydrogenase from Arabidopsis thaliana (AtGALDH) as an examples. Effect of the structure (and charge) of the micelle-forming surfactant itself on the activity of both enzymes has been studied using an anionic surfactant (AOT), a neutral surfactant (Bridge-96), and a mixture of cationic and anionic surfactants (CTAB and AOT) as an examples. The pronounced effect of addition of PC and PE lipids on the activity of AtGALDH and TcGAL has been detected, which manifests as increase in catalytic activity and significant change in the activity profile. This can be explained by formation of the tetrameric form of enzymes and/or protein-lipid complexes. By varying composition and structure of the micelle-forming surfactants (AOT, CTAB, and Brijdge-96 and their combinations) it has been possible to change catalytic properties of the enzyme due to effect of the surfactant on the micelle size, lipid mobility, charge, and rigidity of the matrix itself.
Effect of dexamethasone on human neutrophil adhesion and concomitant secretion
Authors: Galkina S. I , Golenkina E. A , Fedorova N. V , Ksenofontov A. L , Serebryakova M. V , Stadnichuk V. I , Baratova L. A , Sud'ina G. F
Published: April 2024

Neutrophils play a dual role in protecting the body. They are able to penetrate infected tissues and destroy pathogens there, releasing aggressive bactericidal substances. Getting into the surrounding tissues, aggressive secretion products of neutrophils initiate the development of inflammatory processes. Invasion of neutrophils into tissues is observed during the development of pneumonia in patients with lung diseases of various etiologies, including acute respiratory distress syndrome caused by coronavirus disease. The synthetic corticosteroid hormone dexamethasone has a therapeutic effect in the treatment of lung diseases, including reducing mortality in patients with severe Covid-19. The acute (short-term) effect of dexamethasone on neutrophil adhesion to fibrinogen and concomitant secretion was studied. Dexamethasone did not affect either the attachment of neutrophils to the substrate or their morphology. The production of reactive oxygen species (ROS) and nitric oxide (NO) by neutrophils during adhesion also did not change in the presence of dexamethasone. Dexamethasone stimulated the release of metalloproteinases in addition to proteins secreted by neutrophil adhesion under control conditions, and selectively stimulated the release of the free amino acid hydroxylysine, a product of lysyl hydroxylase. Metalloproteinases play a key role and closely interact with lysyl hydroxylase in the processes of rearrangement of the extracellular matrix. The therapeutic effect of dexamethasone may be associated with its ability, by changing the composition of neutrophil secretions, to reorganize the extracellular matrix in tissues, which can lead to improved gas exchange in patients with severe lung diseases.
Simulating Dynamic of Suspended Sediment Flow Based on Data of Primorskaya Water Balance Station
Authors: Bugaets A. N. , Lupakov S. Yu. , Pshenichnikova N. F. , Krasnopeyev S. M.
Published: April 2024

Soil loss rate, suspended load, and suspended sediment discharge were simulated for the drainage basin of the Komarovka R., located at the territory of the former Primorskaya Water Balance, Russian Far East. The study was based on an open-code SWAT model. The model was calibrated and verified using archive measurement data on sediment load and suspended sediment discharge at PWBS by data of Tsentral’nyi hydrological gage (157 km2). The simulation efficiency of the suspended load and suspended sediment discharge corresponds to categories satisfactory and higher. On the average for the drainage basin, the rate of soil washout is 11–12 t/ha per year. The washout rate is maximal in the period of active snow melting. The mean monthly value for April–May is 75 thous. t. The mean annual washout is 171 thous. t, and the maximal is 800 thous. t/year. The mean annual runoff of suspended sediments in the outlet section of the drainage basin is 2.6 thous. t. The highest monthly values of sediment runoff correspond to the period of summer floods in August, when with average of 1 thous. and maximum of 7.7 thous. t. The obtained data on the heterogeneity of the spatial distribution of the simulated values of washout rate are in good agreement with the landscape and climatic features of runoff formation in the drainage river basin. The major errors in the estimation of sediment load are due to the simulation quality of the hydrological regime and dynamics of runoff components that form flood hydrographs.
Modern Dynamics of the Northern Dvina Delta: A Study by Multitemporal Space Images
Authors: Kravtsova V. I. , Vakhnina O. V. , Lebedeva S. V. , Khar’kovets E. G. , Chalova E. R.
Published: April 2024

The long-term dynamics of the Northern Dvina delta was studied with the comparison of space images of 1977 and 2020. A map of delta dynamics, compiled by them, shows that the islands at the delta coastline keep increasing and join to the delta, channel islands in the main branches are increasing, and small watercourses in delta islands become narrower and disappear. However, this long-term tendency of the continuing increase in delta area is now accompanied by the processes of shore erosion in islands at delta coastline from the side of the Dvina Bay.
Regularities in the Variations of Chemical Runoff Module in Rivers of the Lena Basin in 2010–2019
Authors: Dzhamalov R. G. , Vlasov K. G. , Galagur K. G. , Safronova T. I. , Grigor’ev V. Yu. , Efimov V. A. , Reshetnyak O. S. , Oboturov A. S.
Published: April 2024

The space and time variations of the concentrations of the most informative hydrochemical characteristics in the Lena R. basin are analyzed for two periods (2010–2014 and 2015–2019) in accordance with the most stringent standards for water bodies used for fishery. The constructed maps of the normal annual unit-area discharge for these components give a space and time characteristic of water quality and reveal the dynamics of hydrochemical runoff variations in the recent years. The effect of climate on surface-water regime in the Lena basin is also considered. The unit-area discharge for the majority of dissolved substances, primarily, the major ions and nutrients, was found to increase at an increase in the total precipitation and to decrease at an increase in the temperature, in which case the effect of precipitation is higher. The effect of temperature on chemical runoff is more noticeable in rivers with predominantly snow feeding, and the effect of precipitation, in rain-fed rivers
The Experience in Drone Use to Evaluate the Coefficients of Turbulent Diffusion in Small Water Bodies
Authors: Lepikhin A. P. , Lyakhin Yu. S. , Lucnikov A. I.
Published: April 2024

Small lakes and reservoirs located in the zone of active technogenesis are subject to the risk of various emergency situations. The present-day computer technologies, including hydrodynamic computation modules, can be used to effectively estimate and forecast their consequences with the aim to minimize the adverse effect. These models require evaluating the coefficients of horizontal diffusion. The theoretical analysis of such processes is very difficult because of their specifics. Studies aimed at evaluating these coefficients in Russia and other countries are very few, even under the assumption of their homogeneity and isotropy. The modern measurement technologies involving the use of pilotless vehicles, make such studies much simpler. The article discusses the significance of such studies, the technology of their performance, and the results obtained for the Verkhne-Zyryansk Reservoir. A field experiment with the use of eight floats yielded an average estimate of the coefficient of horizontal turbulent diffusion equal to 0.012 m2/s. The specific features of the obtained results are discussed.
Hazards and Risks of Recreation Water Use: Vectors of International Studies. The Impacts of Natural Forces on Recreation Beaches and Human Health
Authors: Andreeva I. V.
Published: April 2024

A series of reviews of foreign publications on the problem of hazards on recreational beaches is completed by the generalization of the objectives, tasks, methods, and conclusions of the studies into the hazards to the public spaces, infrastructure, and vacationers due to waves, currents, erosion, and other natural phenomena and processes. The analysis of the approaches and results of applied hydrodynamic, geomorphological, climatic, and sociological studies is used to formulate ideas promising for the development of the theory and practice of studying he hazards on beaches in Russia.
Experience in Numerical Hydrodynamic Simulation of Long River Reaches
Authors: Belikov V. V. , Aleksyuk A. I. , Borisova N. M. , Vasil’eva E. S. , Glotko A. V.
Published: April 2024

The article formulates the main requirements to numerical algorithms for hydrodynamic 2D-modeling of long and very long river segments with lengths of up to several thousand kilometers. The main feature is the use of adaptive unstructured mesh along with algorithms that give correct values of water surface elevations on coarse mesh, taking into account abrupt changes of bed elevations. A hydrodynamic model of a segment of the Amur R. with a total length of 3 thous. km is presented, which is based on a numerical solution of two-dimensional shallow-water equations (Saint-Venant) by a new high-accuracy algorithm, taking into account road and protection structures in the floodplain. The stages of model construction and verification are described, and the results of calculations for an extraordinary flood in 2013 and a high flood in 2020 are given. Water levels (with estimates of their errors) and the rates of water discharge at gages are given along with flow fields and the inundation zones of floodplain areas.
Simulating the Dynamics of the Characteristics of Snow Cover Formation Regime in the Russian Federation Territory. 1. Field Areas of ER in the Historical Period
Authors: Gusev E. M. , Nasonova O. N. , Kovalev E. E. , Shurkhno E. A.
Published: April 2024

A procedure for calculating various characteristics of snow cover formation, based on the use of the land surface model SWAP, was tested on field areas of the European Russia for a historical period (1967−2019). The comparison of simulation results with observation data showed the good quality of snow water equivalent reproduction at these objects. Variations of the climatic values of snow cover formation characteristics in the historical period were analyzed, revealing trends in changes of these characteristic in field areas in the period under consideration.
Numerical Simulation of Turbulent Mixing in a Shallow Lake for Periods of Under-Ice Convection
Authors: Smirnovsky A. A. , Smirnov S. I. , Bogdanov S. P. , Pal’shin N. I. , Zdorovennov R. E. , Zdorovennova G. E.
Published: April 2024

The article presents the results of application of Implicit Large Eddy Simulation method to numerical simulation of under-ice radiatively driven convection, developing in ice-covered water bodies in the moderate zone at the end of freeze-up period. Studies of the radiatively driven convection are of importance because of the role it plays in the temperature regime of lakes and the functioning of lake ecosystems at the end of freeze-up period. The simulation was carried out with the use of the finite-volume software code SINF/Flag-S, developed in SPbPU. The SIMPLEC algorithm with second-order accuracy was used for ad­vancing in time. The discretization of the convective terms was made with the use of QUICK scheme. The results of calculations were used to study variations in the temperature and pulsation velocity components with periodically varying intensity of external energy pumping during the daily cycle. The dissipation of the kinetic energy, background potential energy, and buoyancy flux were evaluated, and changes in these variables during a daily cycle of radiation impact were calculated. The efficiency mixing of water column was evaluated for the period of development of radiatively driven convection in a model domain simulating a small lake covered by ice.
Changes in the Global Water Exchange by the Results of Historical Experiments on Climate Models under CMIP-6 Project
Authors: Dobrovolskii S. G. , Yushkov V. P. , Solomonova I. V.
Published: April 2024

Long-term (up to 165 years) series of globally averaged values of the main water exchange components, obtained as the result of historic experiments on several dozen (from 34 to 41) climate models of CMIP-6 project, are analyzed. The examined characteristics include variations of evaporation from ocean surface, precipitation over the ocean, effective evaporation from the ocean (total horizontal moisture transfer in the atmosphere from the ocean to land), and total model river runoff from the continents. It is shown that the model precipitation over the ocean effectively filters out the monotonic positive trend in evaporation from the ocean and, therefore, increases the stationarity of the total chain of global water exchange, including long-term changes in the global river runoff.
World Trends in the Use of Aquatic Biological Resources
Authors: Makoedov A. N. , Matishov G. G. , Ponomareva E. N.
Published: April 2024

This article considers global trends in the use of aquatic biological resources in 1950–2020. The number and biomass of most hydrobiont species, which determine the indicators of modern fisheries, are within the historical limits of their natural interannual and long-term dynamics. According to the authors, the resource potential of the World Ocean makes it possible to count on an increase in the production of aquatic biological resources. The increased attention to aquaculture is due not to the state of the stocks of traditional fisheries, but to the economic advantages of commercial cultivation of hydrobionts compared to fishing. First of all, this concerns the areas of the most massive accumulation of the population of the Earth. The experience of China and the countries of Southeast Asia should be taken exclusively in the context of the political, economic, demographic, and other conditions specific to the region. Copying such experience in Russia is hardly possible. In the foreseeable future, fishing will apparently remain a priority for our country, which has significant scientific achievements and practical developments in the field of fish farming.
Reviewed: Integration vs Repatriation: Socioeconomic Potential of the Armenian Diaspora in Russia
Authors: Ryazantsev S. V.
Published: April 2024

The book formulates a reasonable conclusion that the process of integration in Russia of migrants from Armenia (as, indeed, any migrants in any country) is a continuum and does not imply complete assimilation.
Prospects for the development of small nuclear power plants in Russia
Authors: Kalyakin S. G. , Soloviev S. L. , Zaryugin D. G.
Published: April 2024

This article reviews the main properties of the modular design of small nuclear power plants (SNPPs), shows the possibility of reducing the cost and construction time of this class of plants through factory production, the effect of serialization, and the reduction of redundant safety systems. The prospects for significant expansion of the field of application of nuclear technologies due to their modularity and the possibility to ensure high safety performance are presented. Possible areas of SNPP use for power supply of remote territories including the Arctic area, production of high-potential heat and hydrogen for industrial consumers, and other applications are analyzed. It shows the need to develop and implement a new nuclear energy technology platform based on SNPPs to solve the problems of global decarbonization of the world economy by significantly expanding the scope of nuclear energy technologies in addition to the currently developed technological platform of a closed nuclear fuel cycle with fast neutron reactors and the technological platform of controlled thermonuclear fusion. The authors propose to create a pilot site for testing technologies for captive production of hydrogen (heat) for an industrial consumer, as well as other technologies for the utilitarian use of SNPPs based on a pilot demonstration of a nuclear power plant with a high-temperature (about 1100C) fast neutron reactor with a gas coolant.
Dinosaurs of Russia: Sauropods (Sauropodomorpha)
Authors: Averianov A. O. , Lopatin A. V.
Published: April 2024

In Russia, sauropod remains have been found in deposits from the Middle Jurassic of Western Siberia (Mamenchisauridae); the Lower Cretaceous of the Volga region (Volgatitan simbirskiensis), Transbaikalia (Tengrisaurus starkovi), and Western Siberia (Sibirotitan astrosacralis); and the Upper Cretaceous of the Far East (Opisthocoelicaudidae). Most finds from the Lower Cretaceous belong to titanosaurs (Lithostrotia). The Lower Cretaceous deposits of Western Siberia are the most promising in terms of the search for articulated remains of sauropods.
Remote assessment of the characteristics of unexplored lakes of the northern territories
Authors: Zverev I. S. , Rasulova A. M. , Golosov S. D. , Kondratiev S. A.
Published: April 2024

This article proposes a methodology for assessing the hydrophysical and chemical-biological characteristics of unstudied small and medium-sized lakes (with an area of up to 100 km2) in the northern territories of Russia (on the example of Eastern Fennoscandia) using remote sensing methods and mathematical modeling. The methodology is based on the use of a one-dimensional model of hydrothermodynamic processes in reservoirs, FLake. Based on satellite imagery of the underlying surface, the area of the lake is determined, related by private empirical relationships to the average depth, which is the input parameter for applying the model. In addition, a series of meteorological elements of standard measurements are used, obtained from the geographic coordinates of the selected object from the meteorological reanalysis of the ERA5 family. This makes it possible to evaluate the thermal characteristics of a reservoir, as well as calculate the content of dissolved oxygen in various layers of the water mass and the likelihood of anoxic conditions occurring. In this case, contact measurements are not required, which is extremely important when studying the hard-to-reach and little-studied northern territories of our country.
“Digital Core” Technology and Supercomputer Computing
Authors: Balashov V. A. , Savenkov E. B. , Chetverushkin B. N.
Published: April 2024

This article is focused on the modeling of multiphase hydrodynamic flows within “digital core” technology for the needs of the oil and gas industry. The essence of this technology is direct numerical simulation of the flows on the scale of the pore space of oil and gas reservoir rocks with direct resolution of the structure of this space and the dynamics of interphase boundaries. The importance of the development of high-performance computing facilities (supercomputers) for the successful implementation of this technology is emphasized. Work carried out by the Keldysh Institute of Applied Mathematics, RAS, in the field of mathematical models, computational algorithms, and their software implementation is described.
“I have lived a good, interesting, and happy life”: To the 100th anniversary of the birth of Academician V.I. Gol’danskii
Authors: Krupyanskii Yu. F.
Published: April 2024

This article is devoted to the life and work of the outstanding chemical physicist Academician Vitalii Iosifovich Gol'danskii (1923–2001). His scientific interests were wide and included chemical physics, high energy chemistry, nuclear chemistry and physics, particle physics, and biophysics. Among his achievements is the discovery of secondary neutrons arising from the bombardment of nuclei of heavy elements, which formed the basis for the production of plutonium from uranium-238; discovery of electromagnetic polarization of hadrons and quantitative determination of polarizability constants; pioneering work in the field of Mössbauer and positron spectroscopy; discovery of solid-phase polymerization at ultralow temperatures. Touches to the portrait of the scientist are added by the memories of his friends and colleagues.