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Increment of hFIX expression with endogenous intron 1 in vitro

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Cell Research 1997年第1期7卷 21-29页

作者： ZHENG BING XIAO YUN QIU MIN TAN YONG NA XING DARU LU JING LUN XUE XIN FANG QIU(Institute of Genetics, Fudan Univerisity, Shanghai 200433) The first two authors made equally significant contributions to this work.* This paper is dedicated to Professor Lu Ji SHI on the 80th anniversary of his birthdayReceived 27September1996 revised 21April1997 Accepted 29may1997

This paper probes into the feasibility of increasing expression level of hFIX gene with endogenous nitron 1 sequence. hFIX minigene was obtained with middle sequence truncated nitron 1 inserted into the relative site of hFIX cDNA, and plasmid vector pKG5i'IX, retroviral vector GINaCi'IX were constructed. These vectors were transduced into target cells of PA317, C2C12, primary rabbit skin fibroblasts (RSF) and primary human skin fibroblasts (HSF). The expression level of mixed colonies are PA317/pKG5i'IX, 151 "g/106 cells/24h; PA317/GINaCi'IX, 308ng/106 cells/24 h; C2C12/G1 NaCi'IX, 186 ng/106 cells/24 h; RSF/GINaCi'IX, 1929 ng/106 cells/24 h; HSF/GlNaCi'IX, 1646 ng/106 cells/ 24 h. These results indicated that hFIX minigene with nitron 1 is able to increase the expression level to about 3 times of that of hFIX cDNA. Meanwhile, in order to study the application of hFIX minigene in the retroviral-mediated gene transfer system and refrain from nitron splicing during viral production, a retroviral vector GlNaCi'IXR with reversely inserted hFIX minigene expression cassette was constructed. The expression level of reverse constructor in PA317 cells was 390 ng/106 cells/24 h with 79% of bioactivity. PCR detection of HT/GlNaCi'IXR cells infected with PA317/ClNaCi'IXR supernatant confirmed the existence of nitron 1 sequence. These results suggested that expression vector with forward-inserted intronl-carrying hFIX expression cassette can be used in directed gene Human factor IX expression with nitron transfer, but when using the retroviral-mediated gene transfer system, reversely-inserted intronl-carrying hFIX expression cassette should be considered.

关键词： Intron 1 human clotting factor IX (hFIX) gene transfer gene expression reverse inserted sequence

The apoptosis of HEL cells induced by hydroxyurea

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Cell Research 1997年第1期7卷 91-97页

作者： GUI CHANG YUN CHU JIANG HENG YUE XIE RUO LAN QIAN(Shanghai Institute of Cell Biology, Chinese Academy of Sciences, Shanghai 200031) Shanghai Institute of Cell Biology Chinese Academy of Sciences Shanghai 200031&#x0002A Dedicated to Professor Lu Ji SHI's 80th birthday† The project was supported by National Natural Science Foundation of ChinaReceived 19March1997 revised 9April1997 Accepted 5June1997

Hydroxyurea has been used to synchronize cultured cells to S-phase and used to treat patients with sicklecell anemia. Recently, we found that hydroxyurea can induce the apoptosis of HEL (human erythroleukemia) *** induced HEL cells showed ultrastructurally chromatin condensation with regular crescents at the nuclear edges and apoptotic bodies. However, the cells of K562, another human erythroleukemia cell line, did not show such morphological changes. Under fluoroscope, the HEL cells after induction often displayed a clear reduction in nuclear diameter and nuclear chromatin cleavage and condensation and the presence of nuclear ring and apoptotic bodies. Analysis with flow cytometry showed that the percentage of apoptotic cells is about 30-40% after HEL cells were induced by hydroxyurea for 3 days. DNA ladder can be observed by electrophoretic analysis.

关键词： HEL cells hydroxyurea apoptosis

Effect of electromagnetic swirling flow in slide-gate SEN on flow field in square billet continuous casting mold

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Acta Metallurgica Sinica(English Letters) 2012年第5期25卷 347-356页

作者： Dianqiao GENG Hong LEI Jicheng HE Haitao LIU Key Laboratory of National Education Ministry for Electromagnetic Processing of Materials North- eastern University Shenyang 110819 China State Key Laboratory of Rolling 8z Automation Northeastern University Shenyang 110819 ChinaManuscript received 15 March 2012 in revised form 16 may 2012

In order to weaken the bias flow in the submerged entry nozzle （SEN） with slide- gate, the rotating magnetic field was imposed. The numerical method was employed to investigate the effect of rotating magnetic field on the flow field in the SEN and the mold under different slide-gate opening ratios. Numerical results showed that when the slide-gate opening ratio is smaller than 100%, the flow field in the SEN and the mold become asymmetry and there is an obvious circulation under the slide- gate in the SEN. With increasing exciting current, the divergent angle of liquid steel at the SEN outlet increases, the impact depth of liquid steel in the mold decreases. With increasing slide-gate opening ratio, the impact depth of liquid steel in the mold increases and the required exciting current to weaken the bias flow should increase.

关键词： Square billet Electromagnetic swirling flow Slide-gate SEN Continuous casting Bias flow

Gel-state polybenzimidazole proton exchange membranes with flexible alkyl sulfonic acid side chains for a wider operating temperature range(25–240 ℃)

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Journal of Energy Chemistry 2023年第10期85卷 91-101,I0005页

作者： Taizhong Zhu Danyi Zhu Jiazhen Liang Liang Zhang Fei Huang Lixin Xue Center for Membrane Separation and Water Science&Technology College of Chemical EngineeringZhejiang University of TechnologyHangzhou 310014ZhejiangChina College of Chemistry and Materials Engineering Wenzhou UniversityWenzhou 325035ZhejiangChina Received 18 April 2023Revised 30 May 2023Accepted 31

High-temperature proton exchange membrane fuel cells(HT-PEMFC) possess distinct technical advantages of high output power, simplified water/heat management, increased tolerance to fuel impurities and diverse fuel sources, within the temperature range of 120–200 ℃. However, for practical automobile applications, it was crucial to broaden their low-temperature operating window and enable cold start-up capability. Herein, gel-state phosphoric acid(PA) doped sulfonated polybenzimidazole(PBI) proton exchange membranes(PEMs) were designed and synthesized via PPA sol-gel process and in-situ sultone ring-opening reactions with various proton transport pathways based on absorbed PA, flexible alkyl chain connected sulfonic acid groups and imidazole sites. The effects of flexible alkyl sulfonic acid side chain length and content on PA doping level, proton conductivity, and membrane stability under different temperature and relative humidity(RH) were thoroughly investigated. The prepared gel-state membranes contained a self-assembled lamellar and porous structure that facilitated the absorption of a large amount of PA with rapid proton transporting mechanisms. At room temperature, the optimized membrane exhibited a proton conductivity of 0.069 S cm^(-1), which was further increased to 0.162 and 0.358 S cm^(-1)at 80 and 200 ℃, respectively, without additional humidification. The most significant contribution of this work was demonstrating the feasibility of gel-state sulfonated PBI membranes in expanding HT-PEMFC application opportunities over a wider operating range of 25 to 240 ℃.

关键词： Wide temperature range Proton exchange membrane Fuel cell Gel-state Polybenzimidazole

On the history of nuclear matrix manifestation

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Cell Research 1998年第2期8卷 99-103页

作者： ZBARSKY IB(NK. Koltzov Institute of Developmental Biology, Russian Academy of Sciences. 26, Vavilov Street, 117334 Moscow,Russia. e-mail: ibzba ibrran.msk-su) N.K. Koltzov Institute of Developmental Biology Russian Academy of Sciences 26 Vavilov Street Moscow 117334 Russia. E-mail: ibzba@ibrran.msk.suReceived 31March1998 revised 20may1998 Accepted 25may1998

The nonchromatin proteinous residue of the cell nucleus was revealed in our laboratory as early aJs in 1948and then identified by light and electron microscoPy as residual nucleoli. intranuclear network and nuclear envelope before 1960. This structure termed afterwards as 'nuclear residue', 'nuclear skeleton', 'nuclear cage' 3 'nuclearcarcass' etc., was much later (in 1974) isolated, studied,and entitled as 'nuclear matrix' by Berezney and Coffey,to whom the discovery of this residual structure is of ten wronly ascribed. The real history of nuclear matrix manifestation is reported in this paper.

关键词： Nuclear matrix nuclear residue nuclear fractions history of nuc1ear fractionation

The influence of Trichosanthin on the induction of IgE responses to ovalbumin under adjuvant-free condition

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Cell Research 1995年第1期5卷 67-74页

作者： JI YONGYONG CUIHONG YANG MING YEH. (Shanghai Institute of Cell Biology, Chinese Academy of Sciences, Shanghai 200031, China) Shanghai Institute of Cell Biology Chinese Academy of Sciences Shanghai 200031 China.&#x0002A The work is specifically dedicated to Prof. Zhen YAO for his 80-yeaxs birthdayReceived 6March1995 revised 5may1995 Accepted 13may1995

Trichosanthin(TCS) is a potent allergen in mice. It can reproducibly induce specific IgE responses in C57BL/6J mice without the help of adjuvant alum. TCS can bring out the IgE responses to ovabumin(OVA), while OVA itself could not induce IgE responses to it. How- ever, TCS only works when QVA immunization is given one day after TCS immunization. Either time lag in OVA immunization, or immunization of both antigens at the same time, or OVA immunization given first, all has no effect on the induction of IgE responses to OVA. Through analysis of the antibody specificity of hybridoma clones, it indicated that specific antibodies to TCS or OVA were secreted by independent B cell clones. The IgE antibodies showed no polyreactivity to different antigens.

关键词： Trichosanthin ovalbumin allergen IgE response

Prediction model of microwave calcining of ammonium diuranate using incremental improved back-propagation neural network

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Acta Metallurgica Sinica(English Letters) 2011年第1期24卷 34-42页

作者： Yingwei LI Bingguo LIU Jinhui PENG Wei LI Daifu HUANG Libo ZHANG Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming 650093 China Key Laboratory of Unconventional Metallurgy Ministry of Education Kunming University of Scienceand Technology Kunming 650093 China No.272 Nuclear Industry Factory China National Nuclear Corporation Hengyang 421002 ChinaMamlscript received 2~~ May 2010 in revised form 17 October 2010

The incremental improved Back-Propagation （BP） neural network prediction model using the Levenberg-Marquardt algorithm based on optimizing theory is put forward, which can solve the problems existing in the process of calcinations for ammonium diuranate （ADU） by microwave heating, such as long testing cycle, high testing quan- tity, difficulty of optimization for process parameters. Many training data probably were offered by the way of increment batch and the limitation of the system mem- ory could make the training data infeasible when the sample scale was large. The prediction model of the nonlinear system is built, which can effectively predict the experiment of microwave calcining of ADU, and the incremental improved BP neural network is very useful in overeoining the local minimum problem, finding the global optimal solution and accelerating the convergence speed.

关键词： Microwave calcinations ADU Increment BP neural network Prediction

Electrodeposition of aluminum on aluminum surface from molten salt

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Acta Metallurgica Sinica(English Letters) 2011年第6期24卷 443-448页

作者： Wenmao HUANG Xiangyu XIA Bin LIU Yu LIU Haowei WANG Naiheng MA State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong University Shanghai 200240 China Manuscript received 7 March 2011 in revised form 29 June 2011

The surface morphology, microstructure and composition of the aluminum coating of the electrodeposition plates in AlCl3-NaCl-KCl molten salt with a mass ratio of 8：1：1 were investigated by SEM and EDS. The binding force was measured by splat-cooling method and bending method. The results indicate that the coatings with average thicknesses of 12 and 9 μm for both plates treated by simple grinding and phosphating are compacted, continuous and well adhered respectively. Tetramethylammonium chloride （TMAC） can effectively prevent the growth of dendritic crystal, and the anode activation may improve the adhesion of the coating. Binding force analysis shows that both aluminum coatings are strongly adhered to the substrates.

关键词： Aluminum Electrodeposition Surface morphology Molten salt

Influence of Nitrogen Flow Ratio on the Microstructure, Composition, and Mechanical Properties of DC Magnetron Sputtered Zr-B-O-N Films

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Journal of Materials Science & Technology 2012年第11期28卷 981-991页

作者： Tie-Gang Wang Yanmei Liu Tengfei Zhang Doo-In Kim KwanKHo Kim National Core Research Center for Hybrid Materials Solution Pusan National University Busan 609-735 Korea State Key Laboratory of Corrosion and Protection Institute of Metal Research Chinese Academy of SciencesShenyang 110016 China Analysis and Testing Division Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China [Manuscript received may 22 2012 in revised form August 31 2012]

Nanocrystalline ZrB2 film and nanocomposite Zr-B-O-N films were prepared by non-reactive as well as re- active magnetron sputtering techniques, respectively. By means of X-ray diffraction analysis, electron probe microanalysis, X-ray photoelectron spectroscopy, and scanning electron microscopy, the influence of nitrogen flow ratio on the film microstructure and characteristics were investigated systematically, including the depo- sition rate, chemical compositions, phase constituents, grain size, chemical bonding, as well as cross-sectional morphologies. Meanwhile, the hardness and adhesion of above films were also evaluated by micro-indentation method and a scratch tester. With increasing the nitrogen flow ratio, the deposition rate of above films de- creased approximately linearly, whereas the contents of N and O in the films increased gradually and tended to saturation. Moreover, the film microstructure was also altered gradually from a fine columnar microstructure to a featureless glass-structure. As the nitrogen flow ratio was 11.7%, the Zr-B-O-N film possessed an typical nanocomposite structure and presented good mechanical properties. During the process of reactive sputtering of metal borides, the introduction of nitrogen can show a pronounced suppression of columnar grain growth and strong nanocomposite structure forming ability.

关键词： Films DC magnetron sputtering Nanocomposite Microhardness Adhesion