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Chromatin condensation but not DNA integrity of pig sperm is greater in the sperm-rich fraction

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Journal of Animal Science and Biotechnology 2024年第1期15卷 171-181页

作者： Estel Viñolas-Vergés Jordi Ribas-Maynou Isabel Barranco Camila Peres Rubio Sergi Bonet Jordi Roca Marc Yeste Unit of Cell Biology Department of BiologyFaculty of SciencesUniversity of GironaGironaSpain Biotechnology of Animal and Human Reproduction(TechnoSperm) Institute of Food and Agricultural TechnologyUniversity of GironaGironaSpain Department of Medicine and Animal Surgery Faculty of Veterinary ScienceUniversity of MurciaMurciaSpain Catalan Institution for Research and Advanced Studies(ICREA) S08010 BarcelonaSpain

Background Protamination and condensation of sperm chromatin as well as DNA integrity play an essential role during fertilization and embryo *** some mammals,like pigs,ejaculates are emitted in three separate fractions:pre-sperm,sperm-rich(SRF)and post sperm-rich(PSRF).These fractions are known to vary in volume,sperm concentration and quality,as well as in the origin and composition of seminal plasma(SP),with differences being also observed within the SRF ***,whether disparities in the DNA integrity and chromatin condensation and pro-tamination of their sperm exist has not been *** This study determined chromatin protamination(Chromomycin A3 test,CMA_(3)),condensation(Dibromobi-mane test,DBB),and DNA integrity(Comet assay)in the pig sperm contained in the first 10 m L of the SRF(SRF-P1),the remaining portion of the sperm-rich fraction(SRF-P2),and the post sperm-rich fraction(PSRF).While chromatin protamination was found to be similar between the different ejaculate fractions(P>0.05),chromatin condensation was seen to be greater in SRF-P1 and SRF-P2 than in the PSRF(P=0.018 and P=0.004,respectively).Regarding DNA integrity,no differences between fractions were observed(P>0.05).As the SRF-P1 has the highest sperm concentra-tion and ejaculate fractions are known to differ in antioxidant composition,the oxidative stress index(OSi)in SP,calcu-lated as total oxidant activity divided by total antioxidant capacity,was tested and confirmed to be higher in the SRF-P1 than in SRF-P2 and PSRF(0.42±0.06 vs.0.23±0.09 and 0.08±0.00,respectively;P<0.01);this index,in addition,was observed to be correlated to the sperm concentration of each fraction(Rs=0.973;P<0.001).Conclusion While sperm DNA integrity was not found to differ between ejaculate fractions,SRF-P1 and SRF-P2 were observed to exhibit greater chromatin condensation than the *** could be related to the OSi of each fraction.

关键词： Chromatin Condensation DNA integrity Ejaculate fractions Pig Protamination Sperm

Synthesis of two mono-deoxy β-cyclodextrin derivatives as useful tools for confirming DIBAL-H promoted bis-de-O-methylation mechanism

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Chinese Chemical Letters 2012年第12期23卷 1315-1318页

作者： Su Long Xiao De Min Zhou Ming Yang Fei Yu Li He Zhang pierre Sinay Yong Min Zhang State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking University Institut Parisien de Chimie Moleculaire UMR CNRS 7201Universite Pierre et Marie Curie-Paris 64 Place Jussieu Institute for Interdisciplinary Research Jianghan UniversityWuhan Economic and Technological Development Zone

Diisobutylaluminium hydride （DIBAL-H） promotes secondary rim regioselective bis-de-O-methylation of permethylated β- cyclodextrin （β-CD） to give diol 2. To gain an insight into the mechanism of this remarkable regioselective behavior, two corresponding permethylated β-CDs with an alcohol function at either 2- or 3-position were synthesized in our previous study. As a step further to this work, the two compounds were subjected to deoxygenation reaction with tributyltin hydride in the present of 2,2＇- azobisisobutyronitrile affording the corresponding 2- and 3-deoxy permethylated β-CD derivatives （19 and 16）. The structures of these two compounds were characterized by 1D and 2D NMR and HRMS. Compounds 16 and 19 were unable to react with DIBAL- H which suggests that O-2A and O-3B are necessary for DIBAL-H promoted bis-de-O-methylation reaction of permethylated β-CD.

关键词： Cyclodextrin (CD) DIBAL-H Deoxy Synthesis Mechanism

Optimal control of differential quasivariational-hemivariational inequalities with applications

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Science China Mathematics 2024年

作者： Dong-ling Cai Stanis law Migórski Yi-bin Xiao School of Mathematical Sciences University of Electronic Science and Technology of China College of Applied Mathematics Chengdu University of Information Technology Chair of Optimization and Control Jagiellonian University in Krakow

In this paper, we study a new class of differential quasivariational-hemivariational inequalities of the elliptic type. The problem consists of a system coupling the Cauchy problem for an ordinary differential equation with the variational-hemivariational inequalities, unilateral constraints, and history-dependent operators. First,based on the Minty formulation and the continuity of the solution map of a parametrized quasivariationalhemivariational inequality, and a fixed point theorem for a history-dependent operator, we prove a result on the well-posedness. Next, we examine optimal control problems for differential quasivariational-hemivariational inequalities, including a time-optimal control problem and a maximum stay control problem, for which we show the existence of solutions. In all the optimal control problems, the system is controlled through a distributed and boundary control, a control in initial conditions, and a control that appears in history-dependent ***, we illustrate the results by considering a nonlinear controlled system for a time-dependent elliptic equation with unilateral constraints.

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Investigation of Polyacrylate Anion-Exchangers for Separation of Rare Earth Element Complexes with EDTA

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Journal of Rare Earths 2002年第1期20卷 31-35页

作者： Halina Hubicka(Department of Inorganic Chemistry, Faculty of Chemistry, Maria curie Sklodowska university, 20 031 Lublin, Poland) marie curie Sklodowska Univ Fac Chem Dept Inorgan Chem PL-20031 Lublin Poland

The rare earth complexes with EDTA, Ln(edta), show an unusual sequence of affinity for the anion exchangers. The sorption and chromatographic separation of Y 3+ for Nd 3+ complexes with EDTA was studied by using the strongly basic gel and macroporous polyacrylate anion exchangers, Amberlite IRA 458 and Amberlite 958, and the weakly basic gel polyacrylate anion exchanger, Amberlite IRA 68. The investigations on sorption and separation of rare earth complexes with EDTA on the polyacrylate anion exchangers applied mainly in the environment protection so far indicate that they can be applied in anionexchange separation of lanthanide complexes with aminopolycarboxylic acids. It was shown that the weakly basic polyacrylate gel anion exchanger Amberlite IRA 68 is the most effective in purification of Y 3+ from Nd 3+ in comparison with the strongly basic anion exchangers of this type.

关键词： rare earths yttrium neodymium anion exchanger EDTA

Trends in the placement of penile prostheses over he last 17 years in France

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Asian Journal of Andrology 2015年第2期17卷 337-338页

作者： Priscilla Leon Thomas Seisen pierre Mozer Sebastien Beley Morgan Roupret Academic Department of Urology of La Pitie-Salptetriere Assistance-Publique Hopitaux de Paris Faculte de Medecine Pierre et Marie Curie University Paris 6 Paris France UPMC university Paris 06 GRC n5 ONCOTYPE-URO Paris France.

Dear Editor, Erectile dysfunction （ED） currently affects 152 million men worldwide and this number is likely to reach 322 million by 2025.t Penile prostheses （PP） placement remains a last-resort option in cases where organic ED has not been cured by previous medications, notably intracavernosal injection and oral phosphodiesterase type-5 inhibitor.

关键词： ERECTILE DYSFUNCTION EXPERIENCE

Wellposedness of some quasi-linear Schrdinger equations

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Science China Mathematics 2015年第5期58卷 891-914页

作者： CHEMIN Jean-Yves SALORT Delphine Laboratoire J.-L. Lions UMR 7598 Universit'e Pierre et Marie Curie Laboratoire de Biologie Computationnelle et Quantitative UMR 7238Sorbonne Universit'es L'Institut Jacques Monod UMR 7592 Universit'e Paris Diderot

This article is devoted to the study of a quasilinear Schrdinger equation coupled with an elliptic equation on the metric g. We first prove that, in this context, the propagation of regularity holds which ensures local wellposedness for initial data small enough in˙H1/2 and belonging to the Besov space˙B3/22,1. In a second step, we establish Strichartz estimates for time dependent rough metrics to obtain a lower bound of the time existence which only involves the˙B1+ε2,∞norm on the initial data.

关键词：薛定谔方程适定性线性方程 Besov空间时间依赖性椭圆方程拟线性度量

KINETIC FUNCTIONS IN MAGNETOHYDRODYNAMICS WITH RESISTIVITY AND HALL EFFECT

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Acta Mathematica Scientia 2009年第6期29卷 1684-1702页

作者： Philippe G. Le Siddhartha Mishra FlochLaboratoire Jacques-Louis Lions Centre National de la Recherche ScientifiqueUniversit Pierre et Marie Curie (Paris 6) 4 Place Jussieu 75258 Paris France Seminar for Applied Mathematics D-Math ETH HG Raemistrasse Zürich-8092 Switzerland

We consider a nonlinear hyperbolic system of two conservation laws which arises in ideal magnetohydrodynamics and includes second-order terms accounting for magnetic resistivity and Hall effect. We show that the initial value problem for this model may lead to solutions exhibiting complex wave structures, including undercompressive nonclassical shock waves. We investigate numerically the subtle competition that takes place between the hyperbolic, diffusive, and dispersive parts of the system. Following Abeyratne, Knowles, LeFloch, and Truskinovsky, who studied similar questions arising in fluid and solid flows, we determine the associated kinetic function which characterizes the dynamics of undereompressive shocks driven by resistivity and Hall effect. To this end, we design a new class of ＂schemes with eontroled dissipation＂, following recent work by LeFloch and Mohammadian. It is now recognized that the equivalent equation associated with a scheme provides a guideline to design schemes that capture physically relevant, nonclassical shocks. We propose a new class of schemes based on high-order entropy conservative, finite differences for the hyperbolic flux, and high-order central differences for the resistivity and Hall terms. These schemes are tested for several regimes of （co-planar or not） initial data and parameter values, and allow us to analyze the properties of nonclassical shocks and establish the existence of monotone kinetic functions in magnetohydrodynamics.

关键词： hyperbolic conservation law magnetohydrodynamics magnetic resistivity Hall effect undercompressive shock kinetic function

Electrochemical synthesis and the functionalization of few layer graphene in ionic liquid and redox ionic liquid

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Science China Chemistry 2018年第5期61卷 598-603页

作者： Maria Gómez-Mingot Amarnath Chellachamy Anbalagan Hyacinthe Randriamahazaka Jalal Ghilane Universite Paris Diderot Sorbonne Paris Cite ITODYS UMR 7086 CNRS SIELE group Paris 75013 France Laboratoire de Chimie des Processus Biologiques UMR 8229 CNRS University Pierre et Marie Curie College de France Paris 75231 France Chemistry Division Bhabha Atomic Research Centre Trombay Mumbai 400085 India

Electrochemical reductive exfoliation of graphite to few layered graphene(FLG) in presence of 1-ethyl-2,3-dimethyl imidazolium bis(trifluoromethylsulfonyl) imide ionic liquid and redox ionic liquid based ferrocene has been investigated. Thus, by applying a mild negative potential(-2.7 V vs. Fc/Fc^+) to carbon electrode in ionic liquid graphene flakes could be generated. The generated materials have been characterized by X-ray photoelectron spectroscopy, Raman spectroscopy, high resolution transmission electron microscopy and atomic force microscopy. XPS and Raman analysis show that the electrochemical reductive exfoliation provides the formation of FLG. The thickness of the resulting FLG was found to be ranged between 4 and1 nm. HR-TEM images reveal the formation of few graphene layers and in some cases single graphene layer was ***, this electrochemical route conduces to the formation of ionic liquid functionalized FLG. Finally, the reductive exfoliation was further investigated in the presence of redox ionic liquid. XPS and electrochemical measurements confirm the presence of ferrocene.

关键词：氧化还原作用电气化学液体离子拉曼光谱学电子显微镜合成高分辨率

Urolithiasis in inflammatory bowel disease and bariatric surgery

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World Journal of Nephrology 2016年第6期5卷 538-546页

作者： Agapios Gkentzis Michael Kimuli Jon Cartledge Olivier Traxer Chandra Shekhar Biyani Department of Urology St James's University Hospital Department of Urology Tenon Hospital University Pierre and Marie Curie

AIM To analyse current literature focusing on pathogenesis and therapeutic aspects of urolithiasis with inflammatory bowel disease(IBD) and following bariatric surgery. METHODS A systematic literature search was performed using PubMed, supplemented with additional references. Studies assessing the association of IBD or bariatric surgery with renal stones in both paediatric and adulthood were included. RESULTS Certain types of stones are seen more frequently with IBD. Hyperoxaluria and hypocitraturia are the main metabolic changes responsible for urolithiasis. The incidence of renal stones in malabsorptive types of bariatric surgery such as gastric bypass is high; this is not as common in modern restrictive surgical methods. Preventative methods and urine alkalinisation have been shown to be *** Both conditions are associated with renal stones. Patients' counselling and prevention strategies are the mainstay of urolithiasis management in these patients.

关键词：尿路结石并发症治疗方法临床分析