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pH-Dependent Stability of EGX, A Multi-functional Cellulase from Mollusca, Ampullaria crossean

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Acta Biochimica et Biophysica Sinica 2004年第9期36卷 603-608页

作者： Wen-ying LI2, Ji WANG1, Yan-Hong LI1, Ming DING1, Gen-Jun XU1,3. Lan-ying LIU2, and Fu-Kun ZHAO1,3. 1Key laboratory of Proteomics, Institute of Biochemistry and Cell Biology, {3. Institutes for Biological Sciences, the Chinese Academy of Sciences,Graduate School of the Chinese Academy of Sciences, {3. 20003., china 2College of Life Science, Jilin university, Changchun 13.023. china College of Life Science, Zhejiang university of Science and technology, Hangzhou 3.0018, china Key laboratory ofProteomics Institute of Biochemistry and Cell BiologyShanghai Institutes for Biological Sciencesthe Chinese Academy of SciencesGraduate School of the Chinese Academy of SciencesShanghai 200031China

The cellulase activity and stability of EGX, a multi-functional cellulase previously purified from the mollusca Ampullaria crossean, was systematically studied under different pH. The pH induced con- formation and stability change of EGX have been investigated by using the intrinsic fluorescence, ANS fluorescence and CD spectrum. It has been found that the conformation and activity of this cellulase were strongly dependent on the pH. EGX was stable for both the enzyme activity and the conformation from pH 5.6 to pH 7.4. As shown by intrinsic and ANS fluorescence, no red shift of emission maximum occurred and a negligible intensity change was observed at pH 5.6–7.4. The activity of EGX remained about 80% in pH 5.6–7.4 and obviously decreased out of side the pH range. Urea-induced changes in EGX at pH 5.4 and pH 8.0 were measured by intrinsic fluorescence and CD spectrum. At pH 5.4, a significantly red shift of emission maximum occurred when the concentration of urea was 5 M compared to the concentration was 3.M at pH 8.0. The α-helix at pH 5.4 was 40.51% in the absence of urea and 3..04% in the presence of 4 M urea. At pH 8.0 the α-helix was 7.23. in the presence of 4 M urea. The data indicated that EGX was much susceptible to urea-induced unfolding at pH 8.0 and much stable at pH 5.4. The greater pH dependent stability of EGX may allow the enzyme to adequately catalyze the hydrolysis of cellulosic materials under natural or industrial extreme conditions.

关键词： multi-functional cellulase stability Ampullaria crossean fluorescence spectroscopy pH-dependent structural change CD spectrum

Pangenome and multi-tissue gene atlas provide new insights into the domestication and highland adaptation of yaks

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Journal of Animal Science and Biotechnology 2024年第5期15卷 1832-1850页

作者： Daoliang Lan Wei Fu Wenhui Ji Tserang‑Donko Mipam Xianrong Xiong Shi ying Yan Xiong Peng sheng Jiangping Ni Lijun Bai Tongling Shan Xiangdong Kong Jian Li Ministry of Education of Key laboratory of Qinghai‑Tibetan Plateau Animal Genetic Resource and Utilization Southwest Minzu UniversityChengduChina College of Animal&Veterinary Sciences Southwest Minzu UniversityChengduChina Institute of Qinghai‑Tibetan Plateau Southwest Minzu UniversityChengduChina Jiguang Gene Biotechnology Co. Ltd.NanjingChina Chengdu Genepre technology Co. Ltd.ChengduChina shanghai Veterinary Research Institute Chinese Academy of Agricultural SciencesShanghaiChina

Background The genetic diversity of yak,a key domestic animal on the Qinghai-Tibetan Plateau(QTP),is a vital resource for domestication and breeding *** study presents the first yak pangenome obtained through the de novo assembly of 16 yak *** We discovered 290 Mb of nonreference sequences and 504 new *** pangenome-wide presence and absence variation(PAV)analysis revealed 5,120 PAV-related genes,highlighting a wide range of variety-specific genes and genes with varying frequencies across yak *** component analysis(PCA)based on binary gene PAV data classified yaks into three new groups:wild,domestic,and ***,we pro-posed a‘two-haplotype genomic hybridization model'for understanding the hybridization patterns among breeds by integrating gene frequency,heterozygosity,and gene PAV data.A gene PAV-GWAS identified a novel gene(Bos-Gru3.009179)that may be associated with the multirib trait in Jinchuan ***,an integrated transcrip-tome and pangenome analysis highlighted the significant differences in the expression of core genes and the muta-tional burden of differentially expressed genes between yaks from high and low *** analysis across multiple species revealed that yaks have the most unique differentially expressed m RNAs and lnc RNAs(between high-and low-altitude regions),especially in the heart and lungs,when comparing high-and low-altitude *** The yak pangenome offers a comprehensive resource and new insights for functional genomic studies,supporting future biological research and breeding strategies.

关键词： High-and low-altitude Novel genes Pangenome PAV-GWAS Yak

Overexpression of TRPV1 activates autophagy in human lens epithelial cells under hyperosmotic stress through Ca^(2+)-dependent AMPK/mTOR pathway

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International Journal of Ophthalmology(English edition) 2024年第3期17卷 420-434页

作者： Liu-Hui Huang Jiao Lyu sheng Chen Ting-Yi Liang Yu-Qing Rao Ping Fei Jing Li Hai-ying Jin Pei-Quan Zhao Department of Ophthalmology Shanghai Xinhua Hospital Affiliated with Shanghai Jiao Tong University School of MedicineShanghai 200092China Department of Ophthalmology Shanghai Tenth People’s Hospital Affiliated with Shanghai Tongji University School of MedicineShanghai 200072China Centre for Eye Research Australia Royal Victorian Eye and Ear HospitalEast MelbourneVictoria 3002Australia Ophthalmology Department of SurgeryUniversity of MelbourneEast MelbourneVictoria 3002Australia Shenzhen Eye Hospital Shenzhen Key Laboratory of OphthalmologyAffiliated Shenzhen Eye Hospital of Jinan UniversityShenzhen 518040Guangdong ProvinceChina Department of Ophthalmology Shanghai East HospitalSchool of MedicineTongji UniversityShanghai 200120China

●AIM:To explore whether autophagy functions as a cellular adaptation mechanism in lens epithelial cells(LECs)under hyperosmotic stress.●METHODS:LECs were treated with hyperosmotic stress at the concentration of 270,3.0,400,500,or 600 mOsm for 6,12,18,24h in *** chain reaction(PCR)was employed for the mRNA expression of autophagyrelated genes,while Western blotting detected the targeted protein *** transfection of stub-RFP-sens-GFPLC3.autophagy-related double fluorescence lentivirus was conducted to detect the level of autophagy *** electron microscopy was used to detect the existence of *** interfering RNA of autophagy-related gene(ATG)7,transient receptor potential vanilloid(TRPV)1 overexpression plasmid,related agonists and inhibitors were employed to their influence on autophagy related *** cytometry was employed to test the apoptosis and intracellular Ca^(2+)*** membrane potential was measured by JC-1 *** cell counting kit-8 assay was used to calculate the cellular *** wound healing assay was used to evaluate the wound closure *** 6.0 software was utilized to evaluate the data.●RESULTS:The hyperosmotic stress activated autophagy in a pressure-and time-dependent manner in *** 1 protein expression and conversion of LC3. II to LC3. I increased,whereas sequestosome-1(SQSTM1)protein expression *** Ca^(2+)influx was stimulated caused by hyperosmotic stress,levels of mammalian target of rapamycin(mTOR)phosphorylation decreased,and the level of AMP-activated protein kinase(AMPK)phosphorylation increased in the early *** on this evidence,autophagy activation through the Ca^(2+)-dependent AMPK/mTOR pathway might represent an adaptation process in LECs under hyperosmotic *** stress decreased cellular viability and accelerated apoptosis in LECs and cellular migration *** of autophagy by ATG7 knockdown had sim

关键词： cataract posterior capsular opacification lens epithelial cell hyperosmotic stress autophagy apoptosis transient receptor potential vanilloid 1

Simulation of nuclei morphologies for binary alloy

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Science china Mathematics 2010年第11期53卷 2927-2936页

作者： LI DaMing1, & ZHANG PingWen2 1Department of Mathematics, shanghai Jiaotong university, shanghai 200240, {3. 2Key lab of Mathematics and Applied Mathematics, Center for Applied Physics and technology and School of Mathematical Sciences, Peking university, Beijing 100871, {3. 1. Department of Mathematics Shanghai Jiaotong University Shanghai 200240 China2. Key Lab of Mathematics and Applied Mathematics Center for Applied Physics and Technology and School of Mathematical Sciences Peking University Beijing 100871 China

We study the critical nuclei morphologies of a binary alloy by the string method. The dynamic equation of the string, connecting the metastable phase (liquid) and stable phase (solid), is governed by Helmholtz free energy for the binary alloy system at a given temperature. The stationary string through the critical nucleus (saddle point) is obtained if the relaxation time of the string is su?ciently large. The critical nucleus radius and energy barrier to nucleation of a pure alloy with isotropic interface energy in two and three dimensions are calculated, which are consistent with the classical nucleation theory. The critical nuclei morphologies are sensitive to the anisotropy strength of interface energy and interface thickness of alloy in two and three dimensions. The critical nucleus and energy barrier to nucleation become smaller if the anisotropy strength of the interface energy is increased, which means that it is much easier to form a stable nucleus if the anisotropy of the interface energy is considered.

关键词： nucleation crystal morphology string method

Synthesis of New Benzyl Substituted Titanocene Complexes and Their Novel Intramolecular Cyclization

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Chinese Chemical Letters 1997年第4期8卷 305-308页

作者： Yan Long QIAN Ji Ming YANG Wei Quan SUN Yuan LING Ji Ling HUANG(laboratory of Organometallic Chemistry, east china {3. of Science and technology, shanghai 20023.) E china UNIV SCI & TECHNOL ORGANOMET CHEM LABSHANGHAI 200237PEOPLES R CHINA

The synthesis of seven new benzyl substituted titanocene complexes and their novel intramolecular cyclization promoted by halides is reported.

关键词： Chen Li

Single Buffer Using Perovskite-like RE_2Zr_2O_7 Oxides for High Temperature Superconducting Coated Conductors

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稀有金属材料与工程 2011年第S3期40卷 354-357页

作者： ying Liliang, Lu Yuming, Liu Zhiyong, Fan Feng, Gao Bo, Cai Chuanbing shanghai university, shanghai 200444, china shanghai Univ Res Ctr Superconductors & Appl Technol Shanghai 200444 Peoples R China

Single buffer layers of either Gd2Zr2O7 (GZO) or La2Zr2O7 (LZO) with different thickness on highly textured Ni-W tapes were compared with respective to the application of YBa2Cu3.7-δ coated conductors. The superconducting performances are improved as the buffer thickness of GZO or LZO increases up to a critical value, such as 3.0 and 240 nm, respectively. This suggests that a thin buffer layer is insufficient to prevent the Ni diffusion. If the buffer thickness increases further, the superconducting properties degrade, probably due to changes in the microstructure and degradation of the buffer texture. Comparing with LZO, the texture of GZO is hardly dependent on its thickness, due to smaller mismatch for its lattice with that of Ni-W. For both single buffered coated conductors, the superconducting transition temperatures are around 92 K with a transition width less than 1 K. Inductive measurement reveals that the critical current density (Jc) at 77 K in self-field, reaches 1.2 MA/cm2 and 0.77 MA/cm2 for GZO, and LZO, respectively. This implies that the single buffers of GZO and LZO are comparable to standard buffer architectures such as CeO2/YSZ/Y2O3.or CeO2/LZO, being promising for the process simplification and cost reduction.

关键词： coated conductors single buffer biaxial texture

Effects of paclitaxel on proliferation and apoptosis in human acute myeloid leukemia HL-60 cells

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Acta Pharmacologica Sinica 2004年第3期25卷 124-130页

作者： Yun-feng WAN,Xue-qing GUO1,Zheng-hua WANG ,kang ying1,Ming-hui YAO2 1 Department of Pharmacology,shanghai Medical College,Fudan {3.,shanghai 20003. 1United Gene Scientific technology Company,shanghai 200092,china Department of Pharmacology Shanghai Medical College Fudan University United Gene Scientific technology Company Shanghai 200092 China

AIM: To investigate the regulatory effect of paclitaxel on proliferation and apoptosis in human acute leukemia HL- 60 cells. METHODS: HL-60 cell growth was measured by 3.(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tertrazolium bromide (MTT) colorimetric assay. Cell cycle kinetics and apoptosis were analyzed by flow cytometry and micro- scopic examination. In addition, DNA microarrays containing 14400 EST elements were used to investigate the gene expression pattern of HL-60 cells exposed to paclitaxel 1 μmol/L. RESULTS: Paclitaxel inhibited HL-60 cell growth significantly in a dose-dependent and time-dependent manner (P<0.01). Marked cell accumulation in G2/M phase and multinucleated cells were also observed after treatment with paclitaxel 0.1 and 1 μmol/L. Among 14400 EST elements, 277 genes were found to be markedly up- or down-expressed in the HL-60 cells treated with paclitaxel 1 μmol/L for 0.5 h, comprising 210 known genes and 67 unknown genes. CONCLUSION: Paclitaxel suppresses the growth of HL-60 cells in vitro by causing cell-cycle arrest and apoptosis. The results of microarray suggest that paclitaxel initiates apoptosis through multiple mechanisms.

关键词： acute promyelocytic leukemia paclitaxel cultured tumor cells genes apoptosis oligonucleotide array sequence analysis cell cycle HL-60 cells

Effect of Excipients on Stability and Structure of rhCuZn-SOD Encapsulated in PLGA Microspheres

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Chemical Research in Chinese Universities 2004年第3期20卷 323-327页

作者： LIU Ling 1,2 ,GE Yu 1 and YUAN Qin-sheng 1 1. State Key laboratory of Bioreactor Engineering and Institute of Biochemistry,east {3. university of Science and technology.shanghai 20023.,P. R. {3. 2. Public Health School,Nanjing Medical university,Nanjing 210029,P. R. {3. E china Univ Sci & Technol State Key Lab Bioreactor Engn Shanghai 200237 Peoples R China E china Univ Sci & Technol Inst Biochem Shanghai 200237 Peoples R China Nanjing Med Univ Sch Publ Hlth Nanjing 210029 Peoples R China

When a protein is encapsulated into poly( DL -lactide-co-glycolide)(PLGA) microspheres by means of the double-emulsion method,the harsh microspheres formation process including ultrasonification,exposure to an organic solvent and a polymer may cause the denaturation of the protein. In this study,we investigated the enzymatic activity change and the effect of the excipients on the stability of recombinant human Cu,Zn-superoxide dismutase(rhCu,Zn-SOD) during the emulsification. The specific activity recovery was found to be concentration dependent and the excipients involved such as PEG 600 and Tween 20,and trehalose were shown to increase the stability of rhCu,Zn-SOD. The protein structural integrity within the microspheres was analyzed by FTIR. The structure of rhCu,Zn-SOD within PLGA microspheres containing trehalose was found to be similar to that of the native solid state,whereas the protein encapsulated during the preparation in the absence of any excipient changed due to the possible hydrophobic interaction with the polymer. The results suggest that a rational stability strategy for protein to be encapsulated into microspheres should aim at different processes.

关键词： Poly( DL -lactide-co-glycolide)(PLGA) microsphere Recombinant human Cu Zn-superoxide dismutase(rhCu Zn-SOD) Fourier transform infrared(FTIR) spectroscopy Protein stability Excipient

SIMULATION OF BLOOD FLOW IN INTRACRANIAL ICA-PCOMA ANEURYSM VIA COMPUTATIONAL FLUID DYMAMICS MODELING

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Journal of Hydrodynamics 2009年第5期21卷 583-590页

作者： WANG Qing WANG Wei-zhe FEI Zhi-min LIU ying-zheng CAO Zhao-min School of Mechanical Engineering Shanghai Jiao Tong University Shanghai 200240 China Renji Hospital Shanghai Jiao Tong University Shanghai 200001 China

In the present study, hemodynamics of the internal carotid artery-posterior communicating artery （ICA-PComA） was numerically modeled with CFD approach. The steady and pulsating blood flow in the ICA-PComA was simulated. The main concern was placed on the influence of aneurysm geometry on the local hemodynamics by changing the sac diameter and Aspect Ratio （AR） of the aneurysm. The numerical results show the significantly weakened Wall Shear Stress （WSS） and the intensified wall pressure in the aneurysm as AR is increased. Two factors, i.e., low WSS and high pressure of the aneurysm, may play important roles in the fragile change of the aneurysm and the final rupture. The distributions of Time-Averaged WSS （TAWSS）, Oscillatory Shear Index （OSI） and spatial WSS Gradients （WSSG）） were determined and discussed in view of their influences on the evolution of ICA-PComA aneurysm.

关键词： CFD intracranial aneurysm hemodynamics