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Nitrosative stress in human spermatozoa causes cell death characterized by induction of mitochondrial permeability transition-driven necrosis

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Asian Journal of Andrology 2018年第6期20卷 600-607页

作者： Pamela Uribe Maria E Cabrillana Miguel W Forn Favi/m Treulen Rodrigo Boguen Vladimir Isachenko evgenia Isachenko Ratil S inchez Juana V Villegas Center of Reproductive Biotechnology-Scientific and Technological Bioresource Nucleus（CEBIOR-BIOREN） University of La FronteraTemuco 4811230Chile Center of Excellence in Translational Medicine University of La FronteraTemuco 4810296Chile Department of Internal Medicine Faculty of MedicineUniversity of La FronteraTemuco 4781218Chile %aboratory of Andrology Research of Mendoza（LIAM）Institute of Histology and Embriology of Mendoza（IHEM）Histology and Embryology Area Department of Morphology and PhysiologySchool of MedicineNational University of Cuyo and CCT-MendozaCONICETMendoza 5500Argentin SResearch Institute（CIUDA） Medicine FacultyAcencagua UniversityMendoza 5500Argentina Research Group for Reproductive Medicine Cologne UniversityCologne 50937Germany Department of Preclinical Sciences Faculty of MedicineUniversity of La FrenteraTemuco 4781218Chile.

Peroxynitrite is a highly reactive nitrogen species and a potent inducer of apoptosis and necrosis in somatic cells. Peroxynitrite-induced nitrosative stress has emerged as a major cause of impaired sperm function; however, its ability to trigger cell death has not been described in human spermatozoa. The objective here was to characterize biochemical and morphological features of cell death induced by peroxynitrite-mediated nitrosative stress in human spermatozoa. For this, spermatozoa were incubated with and without （untreated control） 3-morpholinosydnonimine （SIN-l）, in order to generate peroxynitrite. Sperm viability, mitochondrial permeability transition （MPT）, externalization of phosphatidylserine, DNA oxidation and fragmentation, caspase activation, tyrosine nitration, and sperm ultrastructure were analyzed. The results showed that at 24 h of incubation with SIN-l, the sperm viability was significantly reduced compared to untreated control （P〈 0.001）. Furthermore, the MPT was induced （P〈 0.01） and increment in DNA oxidation （P 〈 0.01）, DNA fragmentation （P 〈 0.01）, tyrosine nitration （P 〈 0.0001） and ultrastructural damage were observed when compared to untreated control. Caspase activation was not evidenced, and although phosphatidylserine externalization increased compared to untreated control （P 〈 0.001）, this process was observed in 〈10% of the cells and the gradual loss of viability was not characterized by an important increase in this parameter. In conclusion, peroxynitrite-mediated nitrosative stress induces the regulated variant of cell death known as MPT-driven necrosis in human spermatozoa. This study provides a new insight into the pathophysiology of nitrosative stress in human spermatozoa and opens up a new focus for developing specific therapeutic strategies to better preserve sperm viability or to avoid cell death.

关键词： necrosis nitrosative stress oxidative stress peroxynitrite sperm cell death

Post-keratoplasty astigmatism management by relaxing incisions:a systematic review

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Eye and Vision 2017年第1期4卷 174-180页

作者： gaëlle Ho Wang Yin Louis Hoffart Ophthalmology Department Aix-Marseille University-APHMHôpital de la Timone264 rue Saint Pierre13385 Marseille Cedex 5France Institut Fresnel UMR 7249 Aix Marseille UniversitéCNRSCentrale MarseilleDomaine universitaire de Saint-Jérôme Avenue Escadrille Normandie Niemen13397 Marseille cedex 20France CERIMED Aix-Marseille University27 Boulevard Jean-Moulin13385 Marseille cedex 05France Ramsay Générale de Santé Clinique Monticelli-VelodromeMarseilleFrance

Postoperative visual acuity can be limited by post-keratoplasty astigmatism,even with a clear corneal *** management can be performed by selective suture removal,adjustment of sutures,optical correction,photorefractive procedures,wedge resection,intra-ocular lens implantation,intracorneal ring segments,relaxing incisions with or without compression sutures and repeated *** incisions can be made in the graft,graft-host interface or host *** the unpredictability of the method because the flat and steep meridians are usually not orthogonal after penetrating keratoplasty,with asymmetric power distribution,all the studies showed an overall reduction of refractive,keratometric or topographic astigmatism,ranging from 30%to 72%with manual or femtosecond-assisted *** patients with astigmatism higher than 6 diopters had residual cylinder less than or equal to 3 diopters,which can be treated by laser excimer ablation or secondary intraocular lens implantation.

关键词： Penetrating keratoplasty Astigmatic keratotomy Relaxing incisions Femtosecond laser

A novel method to predict static transmission error for spur gear pair based on accuracy grade

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Journal of Central South University 2020年第11期27卷 3334-3349页

作者： LIU Chang SHI Wan-kai Francesca Maria CURÀ Andrea mura State Key Laboratory of Mechanical Transmission Chongqing UniversityChongqing 400044China Department of Mechanical and Aerospace Engineering Politecnico di TorinoTorino 10129Italy

This paper proposes a novel method to predict the spur gear pair’s static transmission error based on the accuracy grade,in which manufacturing errors(MEs),assembly errors(AEs),tooth deflections(TDs)and profile modifications(PMs)are *** the prediction,a discrete gear model for generating the error tooth profile based on the ISO accuracy grade is ***,the gear model and a tooth deflection model for calculating the tooth compliance on gear meshing are coupled with the transmission error model to make the prediction by checking the interference status between gear and *** prediction method is validated by comparison with the experimental results from the literature,and a set of cases are simulated to study the effects of MEs,AEs,TDs and PMs on the static transmission *** addition,the time-varying backlash caused by both MEs and AEs,and the contact ratio under load conditions are also *** results show that the novel method can effectively predict the range of the static transmission error under different accuracy *** prediction results can provide references for the selection of gear design parameters and the optimization of transmission performance in the design stage of gear systems.

关键词： gear transmission error time-varying backlash prediction method accuracy grade

Study of Accident Progression in Unsealed WWER-1000/V320 Reactor during Maintenance

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Journal of Power and Energy Engineering 2016年第8期4卷 68-78页

作者： Pavlin Groudev Marina andreeva Institute for Nuclear Research and Nuclear Energy-Bulgarian Academy of Sciences Sofia Bulgaria

This paper discusses the results obtained during an investigation of WWER-1000 Nuclear Power Plant (NPP) behavior at shutdown reactor during maintenance. For the purpose of the analysis is selected a plant operating state with unsealed primary circuit by removing the MCP head. The reference nuclear power plant is Unit 6 at Kozloduy NPP (KNPP) site. RELAP5/ MOD3.2 computer code has been used to simulate the transient for WWER-1000/V320 NPP model. A model of WWER-1000 based on Unit 6 of KNPP has been developed for the RELAP5/MOD3.2 code at the Institute for Nuclear Research and Nuclear Energy-Bulgarian Academy of Sciences (INRNE-BAS), Sofia. The plant modifications performed in frame of modernization program have been taken into account for the investigated conditions for the unsealed primary circuit. The most specific in this analysis compared to the analyses of NPP accidents at full power is the unavailability of some important safety systems. For the purpose of the present investigation two scenarios have been studied, involving a different number of safety systems with and without operator actions. The selected initiating event and scenarios are used in support of analytical validation of Emergency Operating Procedures (EOP) at low power and they are based on the suggestions of leading KNPP experts and are important in support of analytical validation of EOP at low power.

关键词： Nuclear Power Plant Safety RELAP5/MOD3.2 Computer Code Unsealed WWER Type Reactor Residual Heat Removal System Low Power and Cold Conditions

Size Dependent Heat Conduction in One-Dimensional Diatomic Lattices

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Communications in Theoretical Physics 2016年第4期65卷 517-522页

作者： Tejal N.Shah P.N.ga jjar Bhavan's Sheth R.A. College of Science Khanpur Ahmedabad 380 001 Gujarat India Department of Physics University School of Sciences Gujarat University Ahmedabad 380 009 Gujarat India

We study the size dependency of heat conduction in one-dimensional diatomic FPU-β lattices and establish that for low dimensional material,contribution from optical phonons is found more effective to the thermal conductivity and enhance heat transport in the thermodynamic limit N →∞.For the finite size,thermal conductivity of 1D diatomic lattice is found to be lower than 1D monoatomic chain of the same size made up of the constituent particle of the diatomic *** the present 1D diatomic chain,obtained value of power divergent exponent of thermal conductivity0.428±0.001 and diffusion exponent 1.2723 lead to the conclusions that increase in the system size,increases the thermal conductivity and existence of anomalous energy *** numerical data supports our findings.

关键词： heat conduction thermal conductivity FPU-β diatomic lattice nonequilibrium molecular dynamics

Acquired haemophilia as a complicating factor in treatment of nonmuscle invasive bladder cancer:A case report

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World Journal of Clinical Cases 2023年第22期11卷 5338-5343页

作者： Kateřina Ryšánková Jaromír Gumulec Michal Grepl Jan Krhut Department of Urology University Hospital OstravaOstrava 70852Czech Republic Department of Surgical Studies Faculty of MedicineOstrava UniversityOstrava 70300Czech Republic Department of Haematooncology University Hospital OstravaOstrava 70852Czech Republic Department of Internal Medicine Faculty of MedicineOstrava UniversityOstrava 70300Czech Republic

BACKGROUND Acquired haemophilia(AH)is a serious autoimmune haematological disease caused by the production of auto-antibodies against coagulation factor *** some patients,AH is associated with a concomitant *** case of surgical intervention,AH poses a high risk of life-threatening *** SUMMARY A 60-year-old female patient with multiple recurrences of non-muscle invasive bladder cancer underwent transurethral tumour resection.A severe haematuria developed postoperatively warranting two endoscopic revisions;however,no clear source of bleeding was identified in the *** haematological examination established a diagnosis of *** with factor VIII inhibitor bypass activity and immunosuppressive therapy was initiated *** patient responded well to the therapy and was discharged from the hospital 21 d after the primary *** the 38-mo follow-up,both AH and bladder cancer remained in complete *** AH is a rare,life-threatening haematological *** should be considered in patients with persistent severe haematuria or other bleeding symptoms,especially if combined with isolated activated partial thromboplastin time prolongation.

关键词： Acquired haemophilia A Bladder cancer Bleeding Complication Surgery Case report

Circulating metastasis associated in colon cancer 1 transcripts in gastric cancer patient plasma as diagnostic and prognostic biomarker

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World Journal of gastroenterology 2015年第1期21卷 333-341页

作者： Susen Burock Pia Herrmann ina Wendler Markus Niederstrasser Klaus-Dieter Wernecke Ulrike Stein Charité Comprehensive Cancer Center Invali-denstra?e 8010117 BerlinGermany Experimental and Clinical Research Center Charité University Medicine Berlin and Max- Delbrück-Center for Molecular MedicineRobert-R?ssle-Stra?e 1013125 BerlinGermany Charité University Medicine Berlin Lindenberger Weg 8013125 BerlinGermany Institute of Medical Biometry Charité University Medicine BerlinLuisenstra?e 6510117 BerlinGermany

AIM: To evaluate the diagnostic and prognostic value of circulating Metastasis Associated in Colon Cancer 1(MACC1) transcripts in plasma of gastric cancer ***: We provide for the first time a blood-based assay for transcript quantification of the metastasis inducer MACC1 in a prospective study of gastric cancer patient ***1 is a strong prognostic biomarker for tumor progression and metastasis in a variety of solid *** conducted a study to define the diagnostic and prognostic power of MACC1 transcripts using 76 plasma samples from gastric cancer patients,either newly diagnosed with gastric cancer,newly diagnosed with metachronous metastasis of gastric cancer,as well as follow-up *** were controlled by using plasma samples from 54 tumor-free *** was separated,RNA was isolated,and levels of MACC1 as well as S100A4 transcripts were determined by quantitative ***: Based on the levels of circulating MACC1 transcripts in plasma we significantly discriminated tumorfree volunteers and gastric cancer patients(P gastric cancer patients of each disease stage,compared to tumor-free volunteers: patients with tumors without metastasis(P = 0.005),with synchronous metastasis(P = 0.002),with metachronous metastasis(P = 0.005),and patients during follow-up(P = 0.021).Sensitivity was 0.68(95%CI: 0.45-0.85) and specificity was 0.89(95%CI: 0.77-0.95),***,gastric cancer patients with high circulating MACC1 transcript levels in plasma demonstrated significantly shorter survival whencompared with patients demonstrating low MACC1 levels(P = 0.0015).Furthermore,gastric cancer patients with high circulating transcript levels of MACC1 as well as of S100A4 in plasma demonstrated significantly shorter survival when compared with patients demonstrating low levels of both biomarkers or with only one biomarker elevated(P = 0.001).CONCLUSION: Level

关键词： gastric cancer Plasma Circulating transcripts MACC

Substituting nitrogen and phosphorus fertilizer with optimal amount of crop straw improves rice grain yield,nutrient use efficiency and soil carbon sequestration

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Journal of Integrative Agriculture 2022年第11期21卷 3345-3355页

作者： XIE Jun Blagodatskaya evgenia ZHANG Yu WAN Yu HU Qi-juan ZHANG Cheng-ming WANG Jie ZHANG Yue-qiang SHI Xiao-jun College of Resources and Environment Southwest UniversityChongqing 400716P.R.China Department of Soil Ecology UFZ–Helmholtz Centre for Environmental ResearchHalle 06120Germany Agro-Technological Institute RUDN UniversityMoscow 117198Russia School of River and Ocean Engineering Chongqing Jiaotong UniversityChongqing 400074P.R.China Research Faculty of Agriculture Hokkaido UniversitySapporo 060-8589Japan

Crop straw return after harvest is considered an important way to achieve both agronomic and environmental ***,the appropriate amount of straw to substitute for fertilizer remains unclear.A field experiment was performed from 2016 to 2018 to explore the effect of different amounts of straw to substitute for fertilizer on soil properties,soil organic carbon(SOC)storage,grain yield,yield components,nitrogen(N)use efficiency,phosphorus(P)use efficiency,N surplus,and P surplus after rice *** to mineral fertilization alone,straw substitution at 5 t ha^(-1)improved the number of spikelets per panicle,effective panicle,seed setting rate,1000-grain weight,and grain yield,and also increased the aboveground N and P uptake in *** substitution exceeding 2.5 t ha^(-1)increased the soil available N,P,and K concentrations as compared with mineral fertilization,and different amounts of straw substitution improved SOC storage compared with mineral ***,straw substitution at 5 t ha^(-1)decreased the N surplus and P surplus by up to 68.3 and 28.9%,respectively,compared to mineral *** aboveground N and P uptake and soil properties together contributed 19.3%to the variation in rice grain yield and yield *** substitution at 5 t ha^(-1),an optimal fertilization regime,improved soil properties,SOC storage,grain yield,yield components,N use efficiency(NUE),and P use efficiency(PUE)while simultaneously decreasing the risk of environmental contamination.

关键词： rice SOC storage yield components N surplus P surplus

Polydopamine-coated photoautotrophic bacteria for improving extracellular electron transfer in living photovoltaics

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Nano Research 2024年第2期17卷 866-874页

作者： Melania Reggente Charlotte Roullier Mohammed Mouhib Patricia Brandl Hanxuan Wang Stefano Tacconi Francesco mura Luciana Dini Rossella Labarile Massimo Trotta Fabian Fischer Ardemis A.Boghossian Institute of Chemical Sciences and Engineering(ISIC) Ecole Polytechnique Fédérale de Lausanne(EPFL)Lausanne 1015Switzerland Department of Biology and Biotechnology Charles Darwin Sapienza University of RomeRome 00185Italy Research Center on Nanotechnology Applied for Engineering of Sapienza(CNIS) University of Rome SapienzaRome 00185Italy CNR-IPCF Consiglio Nazionale delle Ricerche–Istituto per i Processi Chimico Fisici Bari 70126Italy Institute of Life Technologies HES-SO Valais-WallisSion 1950Switzerland Institute for Renewable Energy HES-SO Valais-WallisSion 1950Switzerland

Living photovoltaics are microbial electrochemical devices that use whole cell–electrode interactions to convert solar energy to *** bottleneck in these technologies is the limited electron transfer between the microbe and the electrode *** study focuses on enhancing this transfer by engineering a polydopamine(PDA)coating on the outer membrane of the photosynthetic microbe Synechocystis *** coating provides a conductive nanoparticle shell to increase electrode adhesion and improve microbial charge extraction.A combination of scanning electron microscopy(SEM),transmission electron microscopy(TEM),UV–Vis absorption,and Raman spectroscopy measurements were used to characterize the nanoparticle shell under various synthesis *** cell viability and activity were further assessed through oxygen evolution,growth curve,and confocal fluorescence microscopy *** results show sustained cell growth and detectable PDA surface coverage under slightly alkaline conditions(pH 7.5)and at low initial dopamine(DA)concentrations(1 mM).The exoelectrogenicity of the cells prepared under these conditions was also characterized through cyclic voltammetry(CV)and chronoamperometry(CA).The measurements show a three-fold enhancement in the photocurrent at an applied bias of 0.3 V(***/AgCl[3 M KCl])compared to non-coated *** study thus lays the framework for engineering the next generation of living photovoltaics with improved performances using biosynthetic electrodes.

关键词： biophotovoltaics bioelectronics photosynthetic bacteria cyanobacteria polydopamine adherence