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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

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Germanium nanoislands grown by radio frequency magnetron sputtering: Annealing time dependent surface morphology and photoluminescence

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Chinese Physics B 2013年第9期22卷 600-604页

作者： Alireza Samavati Z.Othaman S.K.Ghoshal R.J.Amjad Ibn Sina Institute for Fundamental Science Studies Universiti Teknologi Malaysia Advanced Optical Material Research group Department of PhysicsFaculty of ScienceUniversiti Teknologi Malaysia

Structural and optical properties of ～ 20 nm Ge nanoislands grown on Si（100） by radio frequency （rI） magnetron sputtering under varying annealing conditions are reported. Rapid thermal annealing at a temperature of 600 ℃ for 30 s, 90 s, and 120 s are performed to examine the influence of annealing time on the surface morphology and photoluminescence properties. X-ray diffraction spectra reveal prominent Ge and GeO2 peaks highly sensitive to the annealing time. Atomic force microscope micrographs of the as-grown sample show pyramidal nanoislands with relatively high-density （～ 10^11 cm^-2）. The nanoislands become dome-shaped upon annealing through a coarsening process mediated by Oswald ripening. The room temperature photoluminescence peaks for both as-grown （～ 3.29 eV） and annealed （～ 3.19 eV） samples consist of high intensity and broad emission, attributed to the effect of quantum confinement. The red shift （～ 0.10 eV） of the emission peak is attributed to the change in the size of the Ge nanoislands caused by annealing. Our easy fabrication method may contribute to the development of Ge nanostructure-based optoelectronics.

关键词： germanium nanoislands radio frequency magnetron sputtering photoluminescence surface mor-phology

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Nuclear RAG1 sequence data provide a test of competing evolutionary hypotheses of otophysan fishes (Teleostei:Otocephala)

Nuclear RAG1 sequence data provide a test of competing evolu...

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中国海洋湖沼动物学会鱼类学分会第七届会员代表大会暨朱元鼎教授诞辰110周年庆学术研讨会

作者：彭作刚何舜平 DIOGO Rui Institute of Hydrobiology Chinese Academy of Sciences Laboratory of Functional and Evolutionary morphology University of LiegeB-4000 LiegeBelgium

The monophyletic group of teleostean fish known as the Otophysi(ostariophysan groups excluding Gonorynchiformes),represents about two third of all freshwater fishes and constitutes one of the most diverse vertebrate taxa,including the Cypriniformes(carps and loaches),Characiformes (piranhas and relatives),Siluriformes(catfishes),and Gymnotiformes(knifefishes).To date,there were five competing evolutionary hypotheses regarding the four otophysan groups(orders).The phylogenetic relationship within otophysan fishes remains highly *** present study, approximate 1170 bp nuclear RAG1 sequences of 13 otophysan fishes plus five RAG1 sequences of related groups were retrieved from *** phylogenetic trees,constructed using the maximum parsimony(MP),neighbor-joining(NJ),maximum likelihood(ML)and Bayesian methods,show an identical topology for the four otophysan *** competing otophysan topologies were then tested by using the approximately unbiased test,the Kishino-Hasegawa test,and the Shimodaira-Hasegawa *** results show that the grouping ((((Characiformes,Siluriformes), Gymnotiformes),Cypdniformes),outgroups)is the most likely but there is no significant difference between this one and the other two alternative hypotheses at 5% significant level— ((((Gymnotiformes,Siluriformes),Characiformes),Cypriniformes),outgroups),and ((((Characiformes,Gymnotiformes),Siluriformes),Cypriniformes),outgroups).

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Composition and processing of direct-quench hot rolled steels with ultrahigh strength exceeding GPa

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Journal of Iron and Steel Research International 2021年第6期28卷 703-712页

作者： Qian Zhang Da Ren Zhi-pu Liu Chen-chong Wang Jian Huang Wei Xu State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819LiaoningChina Benxi Iron and Steel group Co. Ltd.Benxi 117002LiaoningChina

The design of high-strength steel has long been discussed in the field of metal structural *** further increase the strength of common high-strength steel and further decrease the cost for production,three direct-quench hot rolled steels were designed and *** rolling and coiling processes were set based on continuous cooling transformation *** addition,the effect of the coiling temperature on the tensile properties was discussed to further guide the optimization of the *** was found that compared with granular bainite,lower bainite probably has more advantages for both the strength and low temperature impact toughness of direct-quench hot rolled *** a process of tailoring the morphology of bainite and controlling the grain boundary precipitation,the newly designed direct-quench hot rolled steels showed greatly improved strength and acceptable ductility/toughness compared with traditional quenched and tempered steels.

关键词： High-strength steel Direct-quench hot rolling Bainite morphology Precipitation Mechanical property

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Solution-combustion Synthesized Nano-pellet α-Al_(2)O_(3) and Catalytic Oxidation of Cyclohexane by Its Supported Cobalt Acetate

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Journal of Wuhan University of Technology(Materials Science) 2021年第6期36卷 811-824页

作者： KONG Xiangyou LIU Wenqiang LIU Xuguang ZHANG Pingping LI Xia WANG Zhiyi College of Materials Science and Engineering Qingdao University of Science and TechnologyQingdao 266042China Guangdong Sitong group Co.Ltd Chaozhou 521000China

Nano-pelletα-Al_(2)O_(3) was prepared using aluminum nitrate as precursor and urea as fuel by a fast method of solution combustion *** formation of the nano material was dependent on the molar ratio of fuel/oxidant,calcination temperature,and foreign metallic *** prerequisite conditions of the formation were a suitable fuel/oxidant molar ratio larger than two and calcination temperature higher than 673 *** ions,Ce^(4+) or Co^(2+),hindered this formation via promoting the generation of stable penta-coordinated Al^(3+) ions due to strong interaction with alumina,were revealed by ^(27)Al NMR *** Al^(3+) ions were recognized as a critical intermediate state for the phase transformation of alumina and their presence deterred the *** nano-pellet morphology of the product demonstrated a specific surface area of 69 m^(2)/g,of which the external surface area occupied 59 m^(2)/*** was found that the supported cobalt acetate on such nano-pellets existed as nanoparticles attached to the external surface,evidenced by the TEM *** prepared catalyst could efficiently catalyze the selective oxidation of cyclohexane under the reaction condition of pressure under 0.8 MPa,temperature at 373 K,and time for 4 *** conversion of the reaction achieved up to 7.9%;while the cyclohexanone selectivity was 42.7%and the cyclohexanone and cyclohexanol selectivity was 91.6%.This catalytic performance recommends the supported cobalt acetate on the inert nano-pellet a-Al_(2)O_(3) as a promising catalyst for the selective oxidation of cyclohexane.

关键词： solution combustion synthesis alumina cyclohexane catalytic oxidation

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Hybrids of gold nanoparticles and oligo(p-phenyleneethynylene)s end-functionalized with alkynylruthenium groups:Outstanding two-photon absorption in the second biological window

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Nano Research 2020年第10期13卷 2755-2762页

作者： Cristóbal Quintana Mahbod Morshedi Jun Du Joseph P.L.Morrall Jan K.Zaręba Marek Samoc Marie P.Cifuentes Mark G.Humphrey I Research School of Chemistry Australian National UnriversityCanberraACT 2601Australia Advanced Materials Engineering and Modelling group Wroclaw University of Science and TechnologyWroclaw 50370Poland

Oligo(p-phenyleneethynylene)s(OPEs)end-capped with(alkynyl)bis(diphosphine)ruthenium and thiol/thiolate groups stabilize ca.2 nm diameter gold nanoparticles(AuNPs).The morphology,elemental composition and stability of the resultant organometallic OPE/AuNP hybrid materials have been defined using a combination of molecular-and nano-material chacterization *** hybrids display long-term stability in solution(more than a month),good solubility in organic solvents,reversible rutheniumcentered oxidation,and transparency beyond 800 nm,and possess very strong nonlinear absorption activity at the first biological window,and unprecedented two-photon absorption activity in the second biological window(σ2 up to 38,000 GM at 1,050 nm).

关键词： gold nanoparticles inorganic materials metal alkynyl complexes nonlinear optics organometallics

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Effects of 3-aminobenzamide on expressions of poly（ADP ribose） polymerase and apoptosis inducing factor in cardiomyocytes of rats with acute myocardial infarction

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Chinese Medical Journal 2009年第11期122卷 1322-1327页

作者： ZHAO Yu-juan WANG Jian-hua FU Bing MA Mu-xin LI Bao-xin HUANG Qi YANG Bao-feng Department of Cardiology First Clinical Medical College Harbin Medical University Harbin 150001 China Pharmacological College Harbin Medical University Harbin 150086 China Centre for Cellular morphology Harbin Medical University Harbin 150086 China

Background Poly（ADP-ribose） polymerase （PARP） plays an important role in cell survival and death. However, the mechanisms involved are not fully understood. Therefore, we investigated the effect of inhibition of PARP on acute myocardial infarction （AMI） at different time points in rats. Methods AMI was induced in rats by ligating the left anterior descending coronary artery. One group received 3-aminobenzamide （3-AB, a kind of PARP inhibitor）（30 mg/kg） by intraperitoneal injection. The changes of ultramicrostructure of cardiocytes in infarction region were noted, PARP cleavage was measured by Western blotting, and expressions of protein of PARP and apoptosis inducing factor （AIF） were measured by immunohistochemical staining after treatment with 3-AB for 2 hours, 4 hours, 6 hours, 1 week, 4 weeks and 8 weeks. Results Few damages to the ultramicrostructure of cardiocytes were observed after treatment with 3-AB. PARP cleavage was detected as early as 4 hours and markedly increased by 6 hours following AMI without 3-AB, but was not found until 6 hours following AMI treated with 3-AB. There were significant differences between 3-AB and AMI groups at the same time points. The expression of PARP was observed gradually increased, but that of AIF was suppressed for 6 hours after treatment of 3-AB, compared with AMI groups in positive cells at the same time points. There was significantly less cleavage of PARP and more PARP expression in 3-AB treated group compared with AMI and control groups at all matched time points. Conclusions Our results suggest that 3-AB inhibits degradation of PARP, increases the expression of PARP protein, and suppresses the expression of AIF protein. Inhibition of PARP activity may protect cardiocytes in rats with AMI and reduce apoptosis.

关键词： 3-aminobenzamide acute myocardial infarction poly(ADP-ribose) polymerase apoptosis inducing factor DNA repair apoptosis

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TISSUE CRYOPRESERVATION AND REWARMING STUDY ON GIANT CELL TUMOR OF BONE

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Science China Chemistry 1982年第12期25卷 1303-1311页

作者：孙德青冯传汉张嘉庆郭振泉蒋化龙 Beijing Medical College People’s Hospital Bone Tumor Research group Dept.Biology.Peking University.Associate Professor

An attempt has been made of cryopreservation of tissue fragments from 6 GCTB surgicalspecimens. They have been kept in 10% DMSO or 15% glycerol medium and stored in liquidnitrogen for periods up to 180 days. Tumor cellular components survive the process of slowfreezing and rapid thawing as cellular growth is successful in subsequent culture. Thoughcertain reversible ultrastructural changes have been detected, no apparent distinction couldbe found in microscopic morphology, motility, growth behavior and LDH isozyme pattern be-tween cultured cells of the cryopreserved fragments and those of the fresh ones. Electronmicroscopy shows that DMSO exceeds glycerol in protecting the ultrastructure of the *** cooling and rapid thawing is recommended because ice-crystals form in the intercellularspace. which causes only light damage to the cells.

关键词： TISSUE CRYOPRESERVATION AND REWARMING STUDY ON GIANT CELL TUMOR OF BONE MGC

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Daicong solution effects on brain ultrastructure in a rat model of Alzheimer's disease

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Neural Regeneration Research 2008年第10期3卷 1107-1110页

作者： Qi＇an Yue Hongyan Wang Shumei Zhao Shengming Zhang Hongjuan Wu Yiguang Wang Fengjie Li Yuanyuan Yang Juanjuan Liu Yuling Ding Department of Microbiology Weifang Medical University Weifang 261042 Shandong Province China Department of Histology and Embryology Weifang Medical University Weifang 261042 Shandong Province China Department of morphology Weifang Medical University Weifang 261042 Shandong Province China Department of Physiology Weifang Medical University Weifang 261042 Shandong Province China Central Laboratory Weifang Medical University Weifang 261042 Shandong Province China

BACKGROUND： Infusion of kainic acid into the basal nuclei induces neuronal excitotoxicity, degeneration and necrosis, resulting in disturbed learning and memory functions. OBJECTIVE： To explore the effects of different doses of traditional Chinese medicine Daicong solution on brain ultrastructure in a rat model of Alzheimer＇s disease. DESIGN, TIME AND SETTING： The randomized, controlled, cellular morphology experiment was performed at the Shandong Provincial Key Laboratory of Molecular Immunology of Weifang Medical University, China from October 2006 to March 2007. MATERIALS： Fifty healthy, Sprague Dawley rats, aged 22-months, were used to establish rat models of Alzheimer＇s disease. The Morris water maze was prepared at the Pharmacometrics Key Laboratory of Weifang Medical University in Shandong Province of China. Traditional Chinese medicine Daicong solution （crude drug 1 g/mL）, composed of radix ginseng, rehmannia dried rhizome, anemarrhenae and radix astragali, was produced by the Department of Pharmacy of Hospital Affiliated to Weifang Medical University. Kainic acid was provided by Professor Xiuyan Li from Weifang Medical University. METHODS： A total of 40 model rats were equally and randomly divided into four groups： dementia model, low-dose Daicong solution （5 g/kg/d）, moderate-dose Daicong solution （10 g/kg/d）, and high-dose Daicong solution （20 g/kg/d）. An additional 10 healthy rats served as the normal control group. Rats in the dementia model and normal control groups received saline （10 mL/kg/d）. MAIN OUTCOME MEASURES： Neural cell ultrastructure was observed utilizing electron microscopy after 1 month of respective treatments. RESULTS： Compared with the normal control group, electron density and the number of ribosomes were significantly reduced in neuronal cytoplasm, and many lipofuscin grains and vacuole-like changes were observed in mitochondria in the dementia model group. In addition, nuclear chromatin presented with different sizes of plaque-shape

关键词： Alzheimer's disease brain Daicong solution morphology

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Investigation on the catalytic effects of AAEM during steam gasification and the resultant char reactivity in oxygen using Shengli lignite at different forms

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International Journal of Coal Science & Technology 2015年第3期2卷 223-231页

作者： Jianxin Mi Ningbo Wang Mingfeng Wang Pengju Huo Dan Liu Hydrocarbon Research Center of Shaanxi YanchangPetroleum (group) Co. Ltd. Xi'an 710075 China

The purpose of this study is to investigate the catalytic effects of alkali and alkaline earth metallic species （AAEM） on char conversion during the gasification in steam and the changes in ex-situ char reactivity in oxygen after the gasification in steam using different forms （i.e. H-form, Na-form） of Shengli brown coal. The surface area, AAEM concentration and carbon crystallite of chars were obtained to understand the change in char reactivity. It was found that not only Na concentration and carbon structure were the main factors governing the char reactivity in the atmosphere of steam and oxygen, but also they interacted each other. The presence of Na could facilitate the formation of disordering carbon structure in char, and the amorphous carbon structure would in turn affect the distribution of Na and thus its catalytic performance. The surface area and pore volume had very little relationship with the char＇s reactivity. Addi- tionally, the morphology of chars from different forms of coals were observed using scanning electron microscope （SEM）.

关键词： Steam gasification H-form coal Na-form coal Char reactivity Char structure

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