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Protective Effects of Vitamin E against Oxidative Damage Induced by Aβ(1-40)Cu(Ⅱ)Complexes

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Acta Biochimica et Biophysica Sinica 2007年第2期39卷 123-130页

作者： Xueling DAI~1 Yaxuan SUN~2 and Zhaofeng JIANG~2 ~1college of Life science,Capital Normal university,Bejing 100037,china ~2college of Applied sciences Humanities of Beijing Union university,Beijing 100083,china collegeofLifescience CapitalNormalUniversityBeijing100037China collegeofAppliedsciencesandHumanitiesofBeijingUnionuniversity Beijing100083China

β-amyloid peptide （Aβ） is considered to be responsible for the formation of senile plaques,which is the hallmark of Alzheimer's disease （AD）.Oxidative stress,manifested by protein oxidation andlipid peroxidation,among other alterations,is a characteristic of AD brain.A growing body of evidence hasbeen presented in support of Aβ1-40forming an oligomeric complex that binds copper at a CuZn superoxidedismutase-like binding site. Aβ1-40Cu（Ⅱ） complexes generate neurotoxic hydrogen peroxide （H2O2） from O2via Cue+ reduction,though the precise reaction mechanism is *** toxicity of Aβ1-40or the Aβ1-40Cu（Ⅱ）complexes to cultured primary cortical neurons was partially attenuated when （+）-α-tocopherol （vitamin E）as free radical antioxidant was added at a concentration of 100 μ*** data derived from lactate dehydro-genase （LDH） release and the formation of H2O2confirmed the results from the MTT *** findingsindicate that copper binding to Aβ1-40can give rise to greater production of H2O2, which leads to a break-down in the integrity of the plasma membrane and subsequent neuronal *** treated with vitaminE exhibited much slighter damage,suggesting that vitamin E plays a key role in protecting neuronal cellsfrom dysfunction or death.

关键词： Aβ1-40Cu(II)complex vitamin E neuronal oxidative damage H2O2 generation lactate dehydrogenase(LDH)release

Cu(Ⅱ) Potentiation of Alzheimer Aβ1-40 Cytotoxicity and Transition on its Secondary Structure

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Acta Biochimica et Biophysica Sinica 2006年第11期38卷 765-772页

作者： Xue-Ling DAI~1 Ya-Xuan SUN~2 Zhao-Feng JIANG~2* 1 college of Life science,Capital Normal university,Beijing 100037,china 2.college of Applied sciences and Humanities,Beijing Union university,Beijing 100083,china collegeofLifescience CapitalNormalUniversityBeijing100037China collegeofAppliedsciencesandHumanities BeijingUnionUniversityBeijing100083China

Mounting evidence has shown that dyshomeostasis of the redox-active biometals such as Cuand Fe can lead to oxidative stress,which plays a key role in the neuropathology of Alzheimer's disease（AD）.Here we demonstrate that with the formation of Cu（Ⅱ）·Aβ1-40 complexes,copper markedly potentiatesthe neurotoxicity exhibited by β-amyloid peptide （Aβ）.A greater amount of hydrogen peroxide was releasedwhen Cu（Ⅱ）·Aβ1-40 complexes was added to the xanthine oxidase/xanthine system detected by potassiumiodide *** bound to Aβ1-40 was observed by electron paramagnetic resonance（EPR） *** dichroism （CD） studies indicated that copper chelation could cause a structuraltransition of Aβ.The addition of copper to Aβ introduced an increase on β-sheet as well as α-helix,whichmay be responsible for the aggregation of Aβ.We hypothesized that Aβ aggregation induced by copper maybe responsible for local injury in *** interaction between Cu2+and Aβ also provides a possible mechanismfor the enrichment of metal ions in amyloid plaques in the AD brain.

关键词： Alzheimer’s disease Cu(Ⅱ)·Aβ1-40 complex neuron injury Aβ secondary structure

Boundary conditions for the bending of a piezoelectric beam

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science china(Physics,Mechanics & Astronomy) 2008年第7期51卷 847-856页

作者： GAO Yang1, XU SiPeng2 & ZHAO BaoSheng3 1 college of science, china Agricultural university, Beijing 100083, china 2.college of Engineering, Ocean university of china, Qingdao 266071, china 3 School of Mechanical Engineering, university of science and Technology Liaoning, Anshan 114044, china college of science China Agricultural University Beijing China college of Engineering Ocean University of China Qingdao China School of Mechanical Engineering University of Science and Technology Liaoning Anshan China

For beam bending in transversely isotropic piezoelectric media, the reciprocal theorem and the general solution of piezoelasticity are applied in a novel way to obtain the appropriate stress and mixed boundary conditions accurate to all orders for the beam of general edge geometry and loadings. By generalizing the method developed by Gregory and Wan, a set of necessary conditions on the edge-data for the existence of a rapidly decaying solution is established. The prescribed edge-data of the beam must satisfy these conditions in order that they could generate a decaying state within the beam. When stress and mixed conditions are imposed on the beam edge, these decaying state conditions for the case of bending deformation of piezoelectric beam are derived explicitly. They are then used for the correct formulation of boundary conditions for the beam theory solution (or the interior solution). Besides, an analytical solution of elastic beam is formulated to verify validity of our boundary conditions. For the stress data, our boundary conditions coincide with those obtained in conventional forms of beam theories. More importantly, the appropriate boundary conditions with two sets of mixed edge-data are obtained for the first time.

关键词： boundary conditions beam bending piezoelectric media decaying states regular states

RNA-binding Domain of the Key Structural Protein P7 for the Rice dwarf virus Particle Assembly

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Acta Biochimica et Biophysica Sinica 2005年第1期37卷 55-60页

作者： Bo-Xiong ZHONG~(1,2*) Yan-Wei SHEN~1 Toshihiro OMURA~2 ~1 Department of Bioresource science.college of animal science,Zhejiang university,Hangzhou 310029,china ~2National Agricultural Research Center,Tsukuba.Ibaraki 305,Japan Department of Bioresource science College of Animal ScienceZhejiang UniversityHangzhou 310029China National Agricultural Research Center TsukubaIbaraki 305Japan

The Rice dwarf virus(RDV)P7 structural protein is the key protein in the RDV *** P7 protein was digested partially or completely by Staphylococcus aureus V8 protease and/orPseudomonas fragi Asp-N *** molecular mass and the N-terminal amino acid sequence of thepolypeptide fragments of the P7 protein were determined by SDS-PAGE and the Edman degradation method,*** the polypeptides were located in the deduced amino acid sequence of the RDV P7 proteinbased on the nucleotide sequence information,with the knowledge of the specific cleavage sites of theStaphylococcus aureus V8 and Pseudomonas fragi Asp-N protease,and the two RNA-binding domains in theP7 protein were *** 1 was located in the residue 128-249 containing 122 amino acids anddomain 2 was located in the residue 325-355 containing 31 amino ***,these two domains may playan important role in the virus particle assembly by contributing to the packaging of viral dsRNAs inside *** two domains may be novel RNA-binding domains,because no amino acid sequences highlysimilar to the conservative sequences of known dsRNA-binding domains reported so *** similaritybetween the motif of domain 1 and the motif of the DNA-binding protein suggests that the DNA-bindingactivity of the RDV P7 protein may be due to this *** similarity between the motif of domain 1 andthe motif of the RNA polymerase domain suggests that the P7 protein may also play a role in RNA synthesis,besides its function in the assembly and subsequent packaging of viral dsRNA into core particles.

关键词： RDV RNA-binding protein protein functional domain virion assembly RNA polymerase

Pathogenic and pathological characteristic of new type gosling viral enteritis first observed in china

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World Journal of Gastroenterology 2001年第5期7卷 678-684页

作者： An-Chun Cheng Ming-Shu Wang Xiao-Yue Chen Yu-Fei Guo Zhao-Yu Liu Peng-Fei Fang college of animal science and veterinary medicine,Sichuan Agricultural university,Xinkang Road,Yaan City 625014,Sichuan Province,china college of animal science and veterinary medicine Sichuan Agricultural University Yaan 625014 Sichuan Province China. Chenganchun@***

AIM: To study the purifying method and characteristics of new gosling viral enteritis virus (NGVEV),the etiological agent of new gosling viral enteritis (NGVE) which was first recognized in china, as well as the pathomorphological development in goslings infected artificially with NGVEV. METHODS: (1)NGVEV virions were purified by the procedure of treatment with chloroform and ammonium sulfate precipitation, dialysis to remove the sulfate radical and ammonium ion and separation by gel filtration chromatography, and SDS-PAGE. (2)Forty-2-day-old White Sichuan goslings were orally administered with NGVEV and 24 hr later 2 birds were randomly selected and killed at 24hr intervals until death occurred. Specimens(duodenum, ileum, liver, heart, kidney, spleen, lung, proventriculus, pancreas, esophagus, and the intestinal embolus) were taken until all birds in this group died and were sectioned and stained with hemotoxylin and eosin and studied by light microscope. RESULTS: NGVEV shared the typical characteristics of Adenovirus and which structural proteins consisted of 15 polypeptides. Necrosis and sloughing of the epithelial cells covering the villus tips of the duodenum were first observed in goslings 2 days postinfection artificially with NGVEV. With the progress of infection, this lesion rapidly occurred in the epithelium at the base of the villus and with infiltration of the inflammatory cells, the jejunum tended to be involved. With the intensification of mucosa necrosis and inflammatory exudation of the small intestine, fibrinonecrotic enteritis was further developed and embolus composed of either intestinal contents wrapped by pseudo-membrane or of the mixture of fibrous exudate and necrotic intestinal mucosa were observed in the middle-lower part of the small intestine. This structure occluded the intestinal tract and made the intestine dilated in appearance. The intestinal glandular cells underwent degeneration, necrosis and might be found sloughed into the lumen.

关键词： Adenoviridae animals Brain china DNA, Viral Enteritis Female Geese Inclusion Bodies, Viral Poultry Diseases Research Support, Non-U.S. Gov't Virulence Viscera

Structures and stability of isomers of[Si,N,N,P]system

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science china Chemistry 2004年第2期47卷 98-105页

作者： KAN Wei1, YU Haitao1, LI Mingxia1, FU Honggang1,2 & SUN Jiazhong1,2 1. college of Chemistry and Chemical Engineering, Heilongjiang university, Harbin 150080, china 2. State Key Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, jilin university, changchun 130023, china college of Chemistry and Chemical Engineering Heilongjiang University Harbin China State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry Jilin University Changchun China

Some stationary points on the potential energy surface of [Si, N, N, P] system were located at the B3LYP/6-311G(d) and QCISD(t)/6-311+G(2df)(single-point) levels of theory, while the isomerization, structures, and stability of these obtained isomers were suggested. The computed results indicate that only four-membered ring isomer SiNPN(E1, 2A'), which possesses butterfly-like structure and Si-P cross bonding, is kinetically stable in all optimized isomers. Other isomers may be considered as kinetically unstable towards isomerization or dissociation because of the corresponding smaller reaction barriers. Furthermore, the present paper also proposes electronic and geometric structures, vibrational frequencies and the corresponding vibrational modes, dipole moments, and rotational constants of isomer E1. To make use of the computed results, we can clearly know that the reaction pathway via an intermediate E3 (SiNPN) is the most favorable channel producing isomer E1 from fragments SiN(2Π) and PN (1Σ), which have been well characterized in space, and thus, isomer E1 can be considered as a candidate for interstellar observation. The reaction enthalpy of SiN(2Π) + PN(1Σ)→ E1 and the standard enthalpy of formation of isomer E1 are 215.25 and 457.99 kJ/mol, respectively, at 298.15 K. Keywords potential energy surface - [Si,N,N,P] system - isomerization - kinetic stability

关键词： potential energy surface, [Si,N,N,P] system, isomerization, kinetic stability.

Mixed boundary conditions for piezoelectric plates

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science china(Physics,Mechanics & Astronomy) 2009年第5期52卷 755-761页

作者： GAO Yang 1 ,XU SiPeng 2 &ZHAO BaoSheng 3 1college of science,china Agricultural university,Beijing 100083,china 2college of Engineering,Ocean university of china,Qingdao 266071,china 3 School of Mechanical Engineering,university of science and Technology of Liaoning,Anshan 114044,china college of science China Agricultural University Beijing China college of Engineering Ocean University of China Qingdao China School of Mechanical Engineering University of Science and Technology of Liaoning Anshan China

For plate bending and stretching problems in piezoelectric materials,the reciprocal theorem and the general solution of piezoelasticity are applied in a novel way to obtain the appropriate mixed boundary conditions accurate to all order.A decay analysis technique is used to establish necessary conditions that the prescribed data on the edge of the plate must satisfy in order that it should generate a decaying state within the *** the case of axisymmetric bending and stretching of a circular plate,these decaying state conditions are obtained explicitly for the first time when the mixed conditions are imposed on the plate *** are then used for the correct formulation of boundary conditions for the interior solution.

关键词： boundary conditions piezoelectric plates mixed data bending problems stretching problems

A New Kind of Shape-stabilized Phase Change Materials

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Journal of Wuhan university of Technology(Materials science) 2011年第3期26卷 491-494页

作者：肖力光 college of Materials science and Engineering Jilin Architectural and Civil Engineering Institute

Based on the lowest melting point and Schroeder’s theoretical calculation formula,nano- modified organic composite phase change materials（PCMs）were *** phase transition temperature and the latent heat of the materials were 24℃and 172 J/g,respectively.A new shape-stabilized phase change materials were prepared,using high density polyethylene as supporting *** PCM kept the shape when temperature was higher than melting ***,it can directly contact with heat transfer *** structure,morphology and thermal behavior of PCM were analyzed by FTIR,SEM and DSC.

关键词： phase change material(PCM) shape-stabilized phase change materials high density polyethylene

^40Ar/^39Ar dating of Daqingshan thrust

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Chinese science Bulletin 2003年第24期48卷 2734-2738页

作者： LIU Zhenghong, XU Zhongyuan & YANG Zhensheng college of Earth sciences, jilin university, changchun 130061, china Correspondence should be addressed to Liu Zhenghong (e-mail: liuzhenghong@***) college of Earth sciences Jilin University Changchun 130061 China

The Daqingshan thrust system, to the south of the Shiguai Mesozoic basin, is a complex system of top-to- the-north thrusting tectonic sheets. The thrust system has a complicated evolution due to multi-stage thrusting. In order to date the thrusting events, syntectonic muscovite and bio-tite grains are respectively analyzed with normal 40Ar/39Ar dating and laser 40Ar/39Ar dating, which yield 2 isochron ages, i.e. 193.74 3.88 Ma and 121.6 1.6 Ma. These ages suggest that faults within the Daqingshan thrust system formed dur-ing 2 stages of thrusting, one the early Indosinian and the other the late Yanshanian. The isotopic dating is consistent with field geological relations. Indosinan deformation is evi-denced by top-to-the-north thrusting, with the occurrence of a series of large-scale east-west trending thrust faults and folds, while the Yanshanian thrusting is characterized by top-to-the-NNW thrusting. It is superposed on and modifies early Indosinian thrust faults.

关键词： Ar 氩中生代云母同位素