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Protective effects of probiotics against methotrexate-induced intestinal toxicity in the mice model

BIOCELL 2025年第1期49卷 7-20页

作者： KSENIA SSTAFEEVA NATALIA ASAMOYLOVA OLGA AKARANDEEVA VERONIKA VNESTEROVA KIRILL ASTARODUBTSEV EVGENY VMIKHAILOV ILYA OKRUTOV EVGENY SPOPOV NATALIA SRODIONOVA ANASTASIA VKOKINA ARTEM PGUREEV Department of Genetics Cytology and BioengineeringBiomedical facultyVoronezh State UniversityVoronezh394018Russia Experimental Pharmacology Department All-Russian Scientific Research Veterinary Institute of Pathology of Pharmacology and TherapyVoronezh394087Russia Department of Service and Restaurant Business Voronezh State University of Engineering TechnologyVoronezh394000Russia Department of Quality Management Hospitality and TourismVoronezh State University of Engineering TechnologyVoronezh394000Russia Laboratory of Metagenomics and Food Biotechnology Voronezh State University of Engineering TechnologyVoronezh394000Russia

Objective:The objective of this study was to determine the level of methotrexate(MTX)toxicity in the intestines of mice and to evaluate the protective effect of probiotics composed of Streptococcus,Bifidobacterium,and Lactobacillus species on intestinal cells during MTX ***:Mice were divided into three groups:control,MTX group(received MTX injections),and MTX+probiotics group(received MTX injections along with a diet containing probiotics).Morphological and histological changes,the level of mitochondrial DNA(mtDNA)damage,the level of lipid peroxidation products,and gene expression in the mice’s small intestine were ***:We demonstrated that intraperitoneal MTX injections significantly increased mtDNA damage in the liver(p<0.001),small intestine(p<0.001),and blood of mice(p<0.01).MTX elevated the quantity of lipid peroxidation products in the liver and small intestine,indicating its strong prooxidative *** induced structural changes in the mice’s intestines,characterized by leukocytic infiltration of *** therapy in mice partially mitigated the morphological and histological changes in the small intestine induced by MTX,reduced oxidative stress,and promoted increased expression of quinone oxidoreductase 1(Nqo1),which participates in both cell protection against oxidative stress and drug/xenobiotic *** prevented the upregulation of the proinflammatory cytokine IL-1b in the small intestine and induced increased expression of genes associated with the Nuclear factor erythroid 2-related factor 2/Antioxidant response element(Nrf2/ARE)pathway,an important mechanism of cell ***:Probiotics can be considered an effective approach to reducing the toxicity of MTX during psoriasis or cancer treatment.

关键词： Small intestine Mitochondrial DNA Mitochondria Il1b Trp53bp1

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Relaxation of Mechanical Stress in Poly(vinyl alcohol) Cryogels of Different Compositions

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Chinese Journal of Polymer science 2023年第3期41卷 442-447,I0010页

作者： Vladimir N.Manzhai Maria S.Fufaeva Ekaterina S.Kashlach Institute of Petroleum Chemistry of the Siberian Branch of the russian Academy of sciences Tomsk 634055Russia

The study presents the experimental results of measurements of the relaxation time of cryogels formed from various colloid-dispersed systems based on a poly(vinyl alcohol) aqueous *** is shown that the value of relaxation time,which characterizes the relationship between the viscosity and elasticity of real bodies,describes the rheological properties of materials more objectively than the traditional assessment of their physical and mechanical characteristics only by the elasticity modulus of the samples.

关键词： Cryogel Relaxation processes Viscoelasticity Rheological properties

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Structural Changes and Electrodynamic Effects in Polymers under Fast Uniaxial Compression

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Chinese Journal of Polymer science 2021年第5期39卷 601-609,I0007页

作者： Aleksey.I.Aleksandrov Ivan A.Aleksandrov Vitaliy G.Shevchenko Aleksandr N.Ozerin N.S.Enikolopov Institute of Synthetic Polymeric Materials RAS 117393 Moscow Profsoyuznaya70 Russian Federation

Rheological explosion in polymers under uniaxial compression in an open volume occurs at the end of continuous rapid plastic deformation after several stages of *** types of polymers were chosen for this study:brittle glassy amorphous polystyrene and thermoplastic semi-crystalline *** pulses were detected during explosion,and their spectra were analyzed with two models.X-ray diffraction methods were used to investigate changes in the structure and morphology of polymers during deformation and rheological *** pores appear in polymer in this process,and their shape and size distribution were derived from X-ray *** main reason for the formation of pores in polymer samples in rheological explosion experiments is the intense microshifts in the polymer volume under the action of high applied pressure.

关键词： Polystyrene Polypropylene X-ray Mechanical properties Compression

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The Dependence of Stellar Activity Cycles on Effective Temperature

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Research in Astronomy and Astrophysics 2022年第12期22卷 198-210页

作者： Leonid Kitchatinov Institute of Solar-Terrestrial Physics SB RAS Lermontov Str.126AIrkutsk 664033Russia

This paper proposes the idea that the observed dependence of stellar activity cycles on rotation rate can be a manifestation of a stronger dependence on the effective temperature. Observational evidence is recalled and theoretical arguments are given for the presence of cyclic activity in the case of sufficiently slow rotation only. Slow rotation means proximity to the observed upper bound on the rotation period of solar-type stars. This maximum rotation period depends on temperature and shortens for hotter stars. The maximum rotation period is interpreted as the minimum rotation rate for operation of a large-scale dynamo. A combined model for differential rotation and the dynamo is applied to stars of different mass rotating with a rate slightly above the threshold rate for the *** show shorter dynamo cycles for hotter stars. As the hotter stars rotate faster, the computed cycles are also shorter for faster rotation. The observed smaller upper bound for rotation period of hotter stars can be explained by the larger threshold amplitude of the α-effect for onset of their dynamos: a larger α demands faster rotation. The amplitude of the(cycling) magnetic energy in the computations is proportional to the difference between the rotation period and its upper bound for the dynamo. Stars with moderately different rotation rates can differ significantly in super-criticality of their dynamos and therefore in their magnetic activity, as observed.

关键词： dynamo stars:activity stars:magnetic field stars:solar-type stars:rotation

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Medium effects in ΛK~＋ pair production by 2.83 GeV protons on nuclei

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Chinese Physics C 2017年第12期41卷 88-105页

作者： E. Ya. Paryev M. Hartmann Yu. T. Kiselev Institute for Nuclear Research Russian Academy of Sciences Moscow 117312 Russia Institute for Theoretical and Experimental Physics Moscow 117218 Russia Institut für Kernphysik and Jülich Centre for Hadron Physics Forschungszentrum Jiilich D-52425 Jiilich Germany

We study ΛK~＋ pair production in the interaction of protons of 2.83 GeV kinetic energy with C, Cu,Ag, and Au target nuclei in the framework of the nuclear spectral function approach for incoherent primary proton–nucleon and secondary pion–nucleon production processes, and processes associated with the creation of intermediate Σ~0K~＋ pairs. The approach accounts for the initial proton and final Λ hyperon absorption, final K~＋ meson distortion in nuclei, target nucleon binding, and Fermi motion, as well as nuclear mean-field potential effects on these *** calculate the Λ momentum dependence of the absolute ΛK~＋ yield from the target nuclei considered, in the kinematical conditions of the ANKE experiment, performed at COSY, within the different scenarios for the Λ-nucleus effective scalar potential. We show that the above observable is appreciably sensitive to this potential in the low-momentum region. Therefore, direct comparison of the results of our calculations with the data from the ANKE-at-COSY experiment can help to determine the above potential at finite momenta. We also demonstrate that the two-step pion–nucleon production channels dominate in the low-momentum ΛK~＋ production in the chosen kinematics and, therefore, they have to be taken into account in the analysis of these data.

关键词： proton-nucleus reactions medium effects hyperon nuclear potential

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Polyhydroxybutyrate/Hydroxyapatite Highly Porous Scaffold for Small Bone Defects Replacement in the Nonload-bearing Parts

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Journal of Bionic Engineering 2017年第4期14卷 648-658页

作者： Fedor Senatov Natalia Anisimova Mikhail Kiselevskiy Aleksey Kopylov Viktor Tcherdyntsev Aleksey Maksimkin National University of science and Technology MISIS Leninskiy pr. 4 Moscow 119049 Russian Federation N.N. Blokhin russian Cancer Research Center Kashirskoye sh. 23 Moscow 115478 Russian Federation

In the present work, Polyhydroxybutyrate （PHB）/Hydroxyapatite （HA） porous composites （10%, 20%, 30 %, 40%, 50% weight HA） were obtained by sintering. PHB/20% HA optimally combines satisfactory mechanical properties with a high content of the bioactive component （HA）. Porous PHB/20% HA scaffolds have shown high mechanical properties （compressive strength of 106 MPa and Young＇s modulus of 901 MPa）. A high volume fraction of interconnected pores （〉 50 vol.%） was achieved with pore size of 50 grn - 500 gm. Biocompatibility of porous pure PHB and PHB/20%HA, as its osseointegration were assessed in vitro and after implantation in laboratory animals. PHB/20% HA （-5% ＋ 0.9%） and pure PHB ~3% ~ 1.4%） samples after 24 hours of incubation with human leucocytes showed no significant level of cytotoxicity when p = 0.648 （p-value）. In vitro massive adhesion of mouse Multipotent Mesenchymal Stromal Cells （MMSC） to the surface of both porous samples was shown. PHB/20% HA induced more intensive MMSC proliferation compared to pure PHB, which are 31% ＋ 6.1% and 20% ＋ 5.7 % respectively when p = 0.039. We observed the resorption （implant surface area was reduced by 49 %） and integration of the porous PHB/20% HA samples into surrounding tissues after 30 days of implantation. The signs of osteoclasts accumulation, neo-angigenesis and new bone formation were observed, which make PHB/20% HA promising for bone tissue engineering.

关键词： polyhydroxybutyrate hydroxyapatite scaffold porous structure implant bone regeneration

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Impact of mine waters on chemical composition of soil in the Partizansk Coal Basin, Russia

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International Soil and Water Conservation Research 2019年第1期7卷 57-63页

作者： Ola Arefieva Alina V.Nazarkina Natalya V.Gruschakova Julia E.Skurikhina Vera B.Kolycheva Far Eastern Federal University 8Sukhanova str.690950VladivostokRussian Federation Institute of Biology and Soil science Far-Eastern BranchRussian Academy of Sciences159Stoletia prospect690022 VladivostokRussian Federation Pacific State Medical University 2Ostryakov Avenue690002VladivostokRussian Federation

Partizansk Coal Basin,located in the south of the russian Far Eastern Region,was intensively mined from 1918 until *** it was mostly explored by underground excavation,the natural landscapes were transformed into anthropogenic *** the mines closed,ground subsidence occurred widely,especially in areas near the waste *** caused water tables to rise to the surface and pollute the *** of the hydrochemical composition of the mine waters were conducted in 2011-2013,and showed low alkalinity and average level of *** can be explained by the fact that while going up through soil mass,the mine waters lost their much of their pollutants due to soil buffering All mine water samples contain thermo-tolerant coliform bacteria *** that indicates a source of fresh fecal *** research indicates increased hydrocarbon ion concentrations in mine waters,especially in autumn,that resulted in accumulation of chromium and copper compounds,which can cause soil pollution.A strong relationship between the chemical composition of the mine waters and soil extracts was found within areas of unregulated groundwater discharge on the *** negative correlation between pH and content of metal compounds including chromium and copper was found at the 'Avangard' mine (r =-0.95);and between alkalinity and chromium content at the 'Glubokaya' mine (r =-0.94).

关键词： Mine waters Soil solution Chemical composition Abandoned coal mines Bacteriological contamination of water

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Protective and water-repellent properties of alkylcarboxylic and alkylphosphonic acid films on technically pure magnesium

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Journal of Magnesium and Alloys 2023年第9期11卷 3272-3286页

作者： Viktoriia A.Luchkina Michael S.Min'kin Andrei Yu Luchkin Yurii I.Kuznetsov Frumkin Institute of Physical Chemistry and Electrochemistry Russian Academy of SciencesLeninskii Pr.31Moscow 119071Russia

The formation of superhydrophobic coatings using low-toxicity corrosion inhibitors is a promising method for corrosion protection of metals and alloys. In this study, the effects of surface roughness and the of the adsorbed substance structure on wettability and corrosion resistance of commercially pure magnesium were investigated. Surface roughness was created by three different methods: paper grinding,etching in nitric acid solution and laser treatment. Oleic, stearic and octadecylphosphonic acids were investigated as potential surface modifiers for the formation of corrosion resistant superhydrophobic coatings. It has been shown that the protective and hydrophobic properties of acid films on magnesium, as well as their stability, are determined by both the initial surface morphology and the nature of the ***, the laser treatment was found to be preferable to mechanical and chemical surface preparation and the best hydrophobic agent among the studied acids is phosphonic acid. The most stable films with excellent superhydrophobic and protective properties in atmospheres of high humidity and salt spray clamber are formed in a solution of 0.001 M octadecylphosphonic acid on the surface of magnesium with high roughness. In addition, the effect of vinyltrimethoxysilane on the protective and hydrophobic properties of stearic acid and octadecylphosphonic acid films was investigated. The results of direct corrosion tests and wetting contact angle degradation kinetics studies showed that the protective and hydrophobic properties of stearic acid can be enhanced by its layer-by-layer adsorption with *** practically reach the parameters of octadecylphosphonic acid.

关键词： Magnesium Corrosion inhibitors Superhydrophobic coatings Alkylcarboxylic acids Alkylphosphonic acid

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Transverse magnetoresistance peculiarities of thermoelectric Lu-doped Bi_2Te_3 compound due to strong electrical disorder

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Journal of Rare Earths 2019年第3期37卷 292-298页

作者： Oleg Ivanov Maxim Yaprintsev Elena Danshina Belgorod State University Belgorod State Technological University named after V.G.Shukhov

The n-type thermoelectric Bi_(1.9)Lu_(0.1)Te_3 was prepared by microwave-solvothermal method and spark plasma sintering. The magnetic field and temperature dependences of transverse magneto resistance measured within temperature 2-200 K interval allow finding the peculiarities characteristic for strongly disordered and inhomogeneous semiconductors. The first peculiarity is due to appearance of linear-inmagnetic field contribution to the total magneto resistance reflected in a crossover from quadratic magnetoresistance at low magnetic fields to linear magneto resistance at high magnetic fields. The linear magnetoresistance can result from the Hall resistance picked up from macroscopically distorted current paths due to local variations in stoichiometry of the compound studied. The second peculiarity is that both linear magnetoresistance magnitude and crossover field are functions of carrier mobility which is in agreement with the Parish and Littlewood model developed for disordered and inhomogeneous semiconductors. An increase in the mobility due to a decrease in temperature is accompanied by an increase in the magnetoresistance magnitude and a decrease in the crossover field. Finally, the third peculiarity is related to the remarkable deviation of the total magnetoresistance measured at various temperatures from the Kohler's rule. Presence of strong inhomogeneity and disorder in the Bi_(1.9)Lu_(0.1)Te_3 structure concluded from the magnetoresistance peculiarities can be responsible for the remarkable reduction in the total thermal conductivity of this compound.

关键词： Bismuth telluride Linear positive magnetoresistance Semiconductors Thermoelectric material Carrier mobility Kohler’s rule

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Theoretical and experimental studies of gas preparation system for pressurization and reactive control system of launch vehicle

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Chinese Journal of Aeronautics 2024年第7期37卷 168-177页

作者： Valeriy TRUSHLYAKOV Vladislav URBANSKY Vadim YUDINTSEV Department of Aviation and Rocket Building Omsk State Technical UniversityOmsk 644050Russia

A new gas preparation system(GasPS-RCS)is proposed to solve two tasks:(A)to heat helium gas for tank pressurization;(B)to prepare gas for the Launch Vehicle(LV)Reactive Control System(RCS)at the LV orientation and stabilization sections of the LV on passive parts of the flight trajectory,to provide conditions for launching the Liquid Rocket Engine(LRE).The system includes a gas generator based on hydrogen peroxide,a separator for water separation,heat exchangers independent of the LRE,and gas-jet *** proposed new system allowed to reduce the length of pressurizing gas lines and reduce the increased helium gas consumption during the heat exchanger warm-up interval of the LRE during its launch.A special advantage of the proposed system is the possibility of ground testing of heat exchangers without an operating LRE.A mathematical model based on the first law of thermodynamics was used to perform a comparative analysis of GasPS-RCS with traditional pressurization and RCS *** validate the mathematical model,the experimental studies of helium pressurizing of a liquid nitrogen tank were *** results show that the deviation of experimental and calculated values for pressure is 1.1%and for temperature up to 2%.According to the results of comparative analysis,the GasPS-RCS is 259 kg lighter for the first stage and 80 kg lighter for the second stage of the LV.

关键词： Engine restart Reactive control system Tank pressurization Cryogenics Hydrogen peroxide Heat exchanger

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