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Mitochondrial complex Ⅰ as a therapeutic target for Alzheimer’s disease

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Acta Pharmaceutica Sinica B 2022年第2期12卷 483-495页

作者： Eugenia Trushina sergey Trushin Md Fayad Hasan Department of Neurology Mayo ClinicRochesterMN 55905USA Department of Molecular Pharmacology and Experimental Therapeutics Mayo ClinicRochesterMN 55905USA

Alzheimer’s disease(AD),the most prominent form of dementia in the elderly,has no *** focused on the reduction of amyloid beta or hyperphosphorylated Tau protein have largely failed in clinical *** therapeutic targets and strategies are urgently *** data suggest that in response to environmental stress,mitochondria initiate an integrated stress response(ISR)shown to be beneficial for healthy aging and ***,we review data that implicate mitochondrial electron transport complexes involved in oxidative phosphorylation as a hub for small molecule-targeted therapeutics that could induce beneficial mitochondrial ***,partial inhibition of mitochondrial complex I has been exploited as a novel strategy for multiple human conditions,including AD,with several small molecules being tested in clinical *** discuss current understanding of the molecular mechanisms involved in this counterintuitive *** this strategy has also been shown to enhance health and life span,the development of safe and efficacious complex Ⅰ inhibitors could promote healthy aging,delaying the onset of age-related neurodegenerative diseases.

关键词： Mitochondria Mitochondria signaling ComplexⅠinhibitors Alzheimer’s disease Integrated stress response Neuroprotection Mitochondria targeted therapeutics Healthy aging

Corrosion Behavior of Reactive Sputtered Al_2O_3 and ZrO_2 Thin Films on Mg Disk Immersed in Saline Solution

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Journal of Materials Science & Technology 2015年第9期31卷 873-880页

作者： Ruben Kotoka sergey Yarmolenko Devdas Pai Jag Sankar Engineering Research Center for Revolutionizing Metallic Biomaterials North Carolina A&T State University

Magnesium has attracted a lot of attention over the last few decades due to its light weight and potential use as biomaterial However, the poor corrosion resistance of magnesium restricts its practical use for ap- plication where exposure to aggressive aqueous media is unavoidable. This paper describes the growth, characterization and corrosion analyses of Al2O3 and ZrO2 thin film coatings aimed at slowing down the fast degradation of Mg in saline solution. In this study, different thicknesses of Al2O3 and ZrO2 were de- posited on pure magnesium （99.95%） disk using pulsed-DC reactive sputtering process. The microstructure and phase analyses were performed using scanning electron microscopy （SEM） and X-ray diffraction （XRD）, respectively. The corrosion protection behavior of the Al2O3 and ZrO2 coated magnesium samples im- mersed in 0,9 wt% NaCl solution were evaluated using electrochemical measurement techniques, such as open-circuit potential （OCP）, potentiodynamic polarization （PD） and electrochemical impedance spectros- copy （EIS）. The microstructural analyses showed that the Al2O3 thin film coatings have circular grains between 5 and 25 nm, while the ZrO2 coatings have bigger ellipsoidal grains. The results from the electrochemical corrosion analyses showed that the Al2O3 coated Mg disk had corrosion resistance of approximately 3 times that of ZrO2 coated Mg disk. It was also observed that increasing the thickness of the Al2O3 coating im- proved the corrosion resistance of the Mg disk. These results suggest that Al2O3 and ZrO2 coating can be used to effectively control the fast degradation of magnesium for medical implant applications.

关键词： Magnetron sputteringMagnesiumAluminum oxideZirconium oxidePorosity

Neurobiological risk factors for problematic social media use as a specific form of Internet addiction:A narrative review

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World Journal of Psychiatry 2023年第5期13卷 160-173页

作者： sergey Yu Tereshchenko Department of Child's Physical and Mental Health Federal Research Center“Krasnoyarsk Science Center of the Siberian Branch of the Russian Academy of Sciences”Research Institute of Medical Problems of the NorthKrasnoyarsk 660022Russia

Problematic social media use(PSMU)is a behavioral addiction,a specific form of problematic Internet use associated with the uncontrolled use of social *** is typical mostly for modern adolescents and young adults,which are the first generations fully grown up in the era of total digitalization of *** modern biopsychosocial model of the formation of behavioral addictions,postulating the impact of a large number of biological,psychological,and social factors on addictive behavior formation,may be quite applicable to *** this narrative review,we discussed neurobiological risk factors for Internet addiction with a focus on current evidence on the association between PSMU and structural/functional characteristics of the brain and autonomic nervous system,neurochemical correlations,and genetic features.A review of the literature shows that the vast majority of the mentioned neurobiological studies were focused on computer games addiction and generalized Internet addiction(without taking into account the consumed content).Even though a certain number of neuroimaging studies have been conducted for PSMU,there is practically no research on neuropeptide and genetic associations for PSMU to *** fact points to the extremely high relevance of such studies.

关键词： Internet computer media

An assessment of the impacts of diesel power plants on air quality in Antarctica

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Advances in Polar Science 2020年第1期31卷 74-87页

作者： sergey KAKAREKA Sviatlana SALIVONCHYK Laboratory on Transboundary Pollution Institute for Nature ManagementNational Academy of Sciences of Belarus220114 MinskBelarus

This study assessed the effects of diesel generators on air quality in the *** devices are the primary energy sources for Antarctic research stations and the main stationary sources of anthropogenic emissions in this *** the Vecherny Oasis,Enderby Land,East Antarctica as an example,NOx,SO2 and PM10 emissions were estimated and surface concentrations of these same pollutants as well as the dry deposition of PM10 were calculated for various periods of exploration of the oasis,based on generator *** values were compared with air quality standards and background air *** areas associated with increased maximum hourly surface concentrations of SO2,NO2 and PM10 over the past 30 a were found to have been reduced by factors of 4355,916 and 1327,*** region affected by increased maximum monthly PM10 deposition has been reduced by a factor of ***,surface concentrations and dry depositions in the Vecherny Oasis were calculated for diesel generators in the same power range as used at Antarctic research *** most powerful diesel generator currently scheduled to be installed in this region was predicted to generate maximum hourly NO2 concentrations above 50μg m^- 3,which is 13 times greater than current *** area over which the PM10 deposition rate will exceed 10 mg m^- 2 month 1 will be increased by a factor of *** technique employed herein has been demonstrated to be applicable to the preliminary assessment of stationary sources of pollutant emissions in Antarctica,including retrospective assessments.

关键词： Antarctica generator emission modeling AERMOD concentration deposition

BER Performance of Finite in Time Optimal FTN Signals for the Viterbi Algorithm

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Journal of Electronic Science and Technology 2020年第1期18卷 42-51页

作者： sergey B.Makarov Ilya I.Lavrenyuk Anna S.Ovsyannikova sergey V.Zavjalov Higher School of Applied Physics and Space Technologies Peter the Great St.Petersburg Polytechnic UniversitySt.Petersburg 195251

In this article, we consider the faster than Nyquist(FTN) technology in aspects of the application of the Viterbi algorithm(VA). Finite in time optimal FTN signals are used to provide a symbol rate higher than the "Nyquist barrier" without any encoding. These signals are obtained as the solutions of the corresponding optimization problem. Optimal signals are characterized by intersymbol interference(ISI). This fact leads to significant bit error rate(BER) performance degradation for "classical" forms of signals. However, ISI can be controlled by the restriction of the optimization problem. So we can use optimal signals in conditions of increased duration and an increased symbol rate without significant energy losses. The additional symbol rate increase leads to the increase of the reception algorithm complexity. We consider the application of VA for optimal FTN signals reception. The application of VA for receiving optimal FTN signals with increased duration provides close to the potential performance of BER,while the symbol rate is twice above the Nyquist limit.

关键词： Bit error rate(BER)performance faster than Nyquist(FTN) Nyquist limit optimal signals Viterbi algorithm(VA)

Preventive effect of a pectic polysaccharide of the common cranberry Vaccinium oxycoccos L. on acetic acid-induced colitis in mice

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World Journal of Gastroenterology 2006年第41期12卷 6646-6651页

作者： sergey V Popov Pavel A Markov Ida R Nikitina sergey Petrishev Vasily Smirnov Yury S Ovodov Department of Molecular Immunology and Biotechnology Institute of PhysiologyKomi Science CentreThe Urals Branch of the Russian Academy of Sciences50 Pervomaiskaya str.Syktyvkar 167982Russia

AIM： To study isolation and chemical characterization of pectin derived from the common cranberry Vaccin/um oxycoccos L. （oxycoccusan OP） and the testing of its preventive effect on experimental colitis. METHODS： Mice were administrated orally with OP two days prior to a rectal injection of 5% acetic acid and examined for colonic damage 24 h later. Colonic inflammation was characterized by macroscopical injury and enhanced levels of myeloperoxidase activity measured spectrophotometrically with o-phenylene diamine as the substrate. The mucus contents of the colon were determined by the Alcian blue dye binding method. Vascular permeability was estimated using 4% Evans blue passage after i.p. injection of 0.05 mol/L acetic acid. RESULTS： In the mice treated with OP, colonic macroscopic scores （1.1 ± 0.4 vs 2.7, P 〈 0.01） and the total square area of damage （10 ± 2 vs 21 ± 7, P 〈 0.01） were significantly reduced when compared with the vehicle-treated colitis group. OP was shown to decrease the tissue myeloperoxidase activity in colons （42 ± 11 vs 112 ± 40, P 〈 0.01） and enhance the amount of mucus of colitis mice （0.9 ± 0.1 vs 0.4 ± 0.1, P 〈 0.01）. The level of colonic malondialdehyde was noted to decrease in OP-pretreated mice （3.6 ± 0.7 vs 5.1 ± 0.8, P 〈 0.01）. OP was found to decrease the inflammatory status of mice as was determined by reduction of vascular permeability （161 ± 34 vs 241 ± 21, P 〈 0.01）. Adhesion of peritoneal neutrophils and macrophages was also shown to decrease after administration of OP （141 ± 50 vs 235 ± 37, P 〈 0.05）. CONCLUSION： Thus, a preventive effect of pectin from the common cranberry, namely oxycoccusan OP, on acetic acid-induced colitis in mice was detected. A reduction of neutrophil infiltration and antioxidant action may be implicated in the protective effect of oxycoccusan.

关键词： Common cranberry Vaccinium oxycoccos L Pectin Colitis Anti-inflammatory Mice

Inventory of unintentional POPs emission from anthropogenic sources in Antarctica

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Advances in Polar Science 2022年第2期33卷 156-166页

作者： sergey KAKAREKA Tamara KUKHARCHYK Institute for Nature Management National Academy of Sciences of Belarus-Laboratory on Transboundary PollutionSkoriny 10 Minsk 220076Belarus

In spite of remote location and very limited human activities,Antarctica is affected by persistent organic pollutants(POPs).POPs investigation in Antarctica has a comparatively long history,but there are still large knowledge gaps in assessment of their emission into *** the paper the results of the first inventory of unintentional POPs emission from anthropogenic sources in Antarctica for modern period and preliminary estimate for the late 1980s are *** of dioxin/furans(PCDD/Fs)emission in different media,as well as polychlorinated biphenyls(PCBs)and hexachlorobenzene(HCB)in air is based on methodology of emission factors and indicators of human *** following sources of POPs emission have been estimated:power generation and heating,waste incineration,mobile sources and open burning of waste(in the past).According to the data obtained,annual PCDD/Fs air emission for modern period comprises 60.74 mg toxic equivalent(TEQ),PCBs-5.09 mg TEQ,and HCB-457.6 *** 2.5 mg TEQ of dioxin/furans is released to residues,so total PCDD/Fs emission is amounted 63.23 mg *** incineration makes the greatest contribution to POPs emission(96% of PCDD/Fs,98%of PCBs and 36% of HCB air emission).In late 1980s open burning of waste was the major source of *** assessment shows that over a 30-year period air emissions of PCDD/Fs decreased about 13 times,PCBs-15 times and HCB-57 times,primarily due to the prohibition of open burning of waste in compliance with the Protocol on Environmental Protection to the Antarctic Treaty requirements.

关键词： persistent organic pollutants emission inventory PCDD/Fs PCBs HCB

Power-law multi-wave model for COVID-19 propagation in countries with nonuniform population density

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Quantitative Biology 2022年第2期10卷 150-156页

作者： Pavel Grinchuk sergey Fisenko A.V.Luikov Heat and Mass Transfer Institute National Academy of Sciences of BelarusMinsk 220072Belarus

Background: The purpose of our study is to develop a quite precise mathematical model which describes epidemics spread in a country with non-uniform population density. This model gives explanation of quite long duration of the peak of a respiratory infection such as the coronavirus disease 2019 (COVID-19).Methods: The theory of kinetic equations and fractal analysis are used in our mathematical model. According to our model, COVID-19 spreading takes the form of several spatio-temporal waves developing almost independently and simultaneously in areas with different population density. The intensity of each wave is described by a power-law dependence. The parameters of the dependence are determined by real statistical data at the initial stage of the disease ***: The results of the model simulation were verified using statistical data for the Republic of Belarus. Based on the developed model, a forecast calculation was made at the end of May, 2020. It was shown that the epidemiological situation in the Republic of Belarus is well described by three waves, which spread respectively in large cities with the highest population density (the first wave), in medium-sized cities with a population of 50−200 thousands people (the second wave), in small towns and rural areas (the third wave). It was shown that a new wave inside a subpopulation with a lower density was born 20−25 days after the appearance of the previous wave. Comparison with actual data several months later showed that the accuracy of forecasting the total number of cases for a period of 3 months for total population in the proposed approach was approximately 3%.Conclusions: The high accuracy mathematical model is proposed. It describes the development of a respiratory epidemic in a country non-uniform population density without quarantine. The model is useful for predicting the development of possible epidemics in the future. An accurate forecast allows to correctly allocating available resources t

关键词： COVID-19 forecast model simultaneous waves population density

Hepatitis B virus markers in hepatitis B surface antigen negative patients with pancreatic cancer:Two case reports

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World Journal of Hepatology 2022年第7期14卷 1512-1519页

作者： sergey Batskikh sergey Morozov Dmitry Kostyushev Department of Hepatology Moscow Clinical Research Center named after A.S.LoginovMoscow 111123Russia Department of Gastroenterology Hepatology and NutritionFederal Research Center of Nutrition and BiotechnologyMoscow 115446Russia Laboratory of Genetic Technologies Martsinovsky Institute of Medical ParasitologyTropical and Vector-Borne DiseasesFirst Moscow State Medical University(Sechenov University)Moscow 119991Russia Division of Biotechnology Sirius University of Science and TechnologySochi 354340Russia

BACKGROUND Hepatitis B virus(HBV)is a known carcinogen that may be involved in pancreatic cancer *** of HBV biomarkers[especially expression of HBV regulatory X protein(HBx)]within the tumor tissue may provide direct support for ***,there is still a lack of such reports,particularly in non-endemic regions for HBV *** we present two cases of patients with pancreatic ductal adenocarcinoma,without a history of viral hepatitis,in whom the markers of HBV infection were detected in blood and in the resected pancreatic *** SUMMARY The results of examination of two patients with pancreatic cancer,who gave informed consent for participation and publication,were the source for this *** standards of care,special examination to reveal occult HBV infection was *** included blood tests for HBsAg,anti-HBc,anti-HBs,HBV DNA,and pancreatic tissue examinations with polymerase chain reaction for HBV DNA,pregenomic HBV RNA(pgRNA HBV),and covalently closed circular DNA HBV(cccDNA)and immunohistochemistry staining for HBxAg and *** subjects were operated on due to pancreatic ductal adenocarcinoma and serum HBsAg was not ***,in both of them anti-HBc antibodies were detected in blood,although HBV DNA was not *** of the resected pancreatic tissue gave positive results for HBV DNA,expression of HBx,and active cellular proliferation by Ki-67 index in both ***,HBV pgRNA and cccDNA were detected only in case *** These cases may reflect potential involvement of HBV infection in the development of pancreatic cancer.

关键词： Pancreatic cancer Pancreatic ductal adenocarcinoma Hepatitis B virus Previous hepatitis B Anti-HBc Hepatitis B virus X antigen