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Transcription and regulation of hepatitis B virus genes in host sperm cells

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Asian Journal of Andrology 2018年第3期20卷 284-289页

作者： Ying Zhong dong-Ling Liu Mohamed Morsi M Ahmed Peng-Hao Li Xiao-Ling Zhou Qing-dong xie Xiao-Qing Xu Ting-Ting Han Zhi-Wei Hou Ji-Hua Huang Lan Xu Tian-Hua Huang Department of Genetics Chengdu Jinxin Research Institute for Reproductive Medicine and Genetics Chengdu 610066 China Research Center for Reproductive Medicine Shantou University Medical College Shantou 515041 China Department of Gynecology and Obstetrics The First Affiliated Hospital Shantou University Medical College Shantou 515041 China

To investigate whether transcription of hepatitis B virus （HBV） gene occurs in human sperm, total RNA was extracted from sperm of patients with chronic HBV infection （test-I）, from donor sperm transfected with a plasmid containing the full-length HBV genome （test-2）, and from nontransfected donor sperm （control）, used as the template for reverse transcription-polymerase chain reaction （RT-PCR）. Positive bands for HBV DNA were observed in the test groups but not in the control. Next, to identify the role of host genes in regulating viral gene transcription in sperm, total RNA was extracted from 2-cell embryos derived from hamster oocytes fertilized in vitro by HBV-transfected （test） or nontransfected （control） human sperm and successively subjected to SMART-PCR, suppression subtractive hybridization, T/A cloning, bacterial amplification, microarray hybridization, sequencing and the Basic Local Alignment Search Tool （BLAST） search to isolate differentially expressed genes. Twenty-nine sequences showing significant identity to five human gene families were identified, with chorionic somatomammotropin hormone 2 （CSH2）, eukaryotic translation initiation factor 4 gamma 2 （EIF4G2）, pterin-4 alpha-carbinolamine dehydratase 2 （PCBD2）, pregnancy-specific beta-l-glycoprotein 4 （PSG4） and titin （TTN） selected to represent target genes. Using real-time quantitative RT-PCR （qRT-PCR）, when CSH2 and PCBD2 （or EIF4G2, PSG4 and TTN） were silenced by RNA interference, transcriptional levels of HBV s and x genes significantly decreased （or increased）（P 〈 0.05）. Silencing of a control gene in sperm did not significantly change transcription of HBV s and x genes （P 〉 0.05）. This study provides the first experimental evidence that transcription of HBV genes occurs in human sperm and is regulated by host genes.

关键词： embryo hepatitis B virus host gene regulation sperm transcription

Synthesis and application of a novel star-hyperbranched poly(acrylic acid) for improved dental restoratives

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Journal of Biomedical Science and Engineering 2010年第11期3卷 1050-1060页

作者： Jun Zhao Yiming Weng dong xie Department of Biomedical Engineering Purdue School of Engineering and Technology Indiana University-Purdue University

A new star-hyperbranched poly(acrylic acid) has been synthesized and incorporated into dental glassionomer cement for enhanced mechanical strengths. The effects of arm number and branching on viscosity of the polymer aqueous solution and mechanical strengths of the formed experimental cement were evaluated. It was found that the higher the arm number and the more the branching, the lower the viscosity of the polymer solution as well as the mechanical strengths of the formed cement. It was also found that the experimental cement exhibited significantly higher mechanical strengths than commercial Fuji II LC. The experimental cement was 51% in CS, 55% in compressive modulus, 118% in DTS, 82% in FS, 18% in FT and 85% in KHN higher than Fuji II LC. The experimental cement was only 6.7% of abrasive and 10% of attritional wear depths of Fuji II LC in each wear cycle. It appears that this novel experimental cement is a clinically attractive dental restorative and may potentially be used for high-wear and high-stress-bearing site restorations.

关键词： Star-Hyperbranched Poly(Acrylic Acid) Light-Cured Glass-Ionomer Cement Atom-Transfer Radical Polymerization Mechanical Strength

Simulation Study on the Controllable Dielectrophoresis Parameters of Graphene

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Chinese Physics Letters 2017年第4期34卷 71-74页

作者： Jian-Long Ji Ya-Li Liu Yang Ge Sheng-dong xie Xi Zhang Sheng-Bo Sang Ao-Qun Jian Qian-Qian Duan Qiang Zhang Wen-dong Zhang Key Lab of Advanced Transducers and Intelligent Control System(Ministry of Education) Taiyuan University of TechnologyTaiyuan 030024 Advanced Coal Mine Machinery and Equipment Collaborative Innovation Center of Shanxi Province Taiyuan University of TechnologyTaiyuan 030024

The method of using dielectrophoresis （DEP） to assemble graphene between micro-electrodes has been proven to be simple and efficient. We present an optimization method for the kinetic formula of graphene DEP, and discuss the simulation of the graphene assembly process based on the finite element method. The simulated results illustrate that the accelerated motion of graphene is in agreement with the distribution of the electric field squared gradient. We also conduct research on the controllable parameters of the DEP assembly such as the alternating current （AC） frequency, the shape of micro-electrodes, and the ratio of the gap between electrodes to the characteristic/geometric length of graphene （λ）. The simulations based on the Clausius-Mossotti factor reveal that both graphene velocity and direction are influenced by the AC frequency. When graphene is close to the electrodes, the shape of micro-electrodes will exert great influence on the velocity of graphene. Also, λ has a great influence on the velocity of graphene. Generally, the velocity of graphene would be greater when λ is in the range of 0.4 0.6. The study is of a theoretical guiding significance in improving the precision and efficiency of the graphene DEP assembly.

关键词： DEP Simulation Study on the Controllable Dielectrophoresis Parameters of Graphene

A High-Strength Cement System for Improved Dental Restoratives

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Journal of Materials Science and Chemical Engineering 2014年第3期2卷 1-15页

作者： dong xie Jun Zhao Yiming Weng Department of Biomedical Engineering Purdue School of Engineering and Technology Indiana University-Purdue University at Indianapolis Indianapolis USA

We have developed and studied a novel high-strength glass-ionomer cement system composed of poly(acrylic acid) with different molecular architectures. These poly(acrylic acid) polymers were synthesized via ATRP technique. The effects of arm number and branching on reaction kinetics, viscosity, and mechanical strengths of the formed polymers and cements were evaluated. The results showed that unlike the star-shaped polymer synthesis both hyperbranched and star-hyperbranched polymers syntheses proceed slowly at the early stage but accelerate at the later stage. The higher the arm number and initiator concentration are, the faster the ATRP reaction was. It was also found that the higher the arm number and branching that the polymer had, the lower the viscosity of the polymer aqueous solution is and the lower the mechanical strengths of the formed cement are. The mechanical strengths of three synthesized polymers-composed experimental cements were very similar to each other but much higher than those of Fuji II LC. The experimental cements were 31% - 53% in CS, 37% - 55% in compressive modulus, 80% - 126% in DTS, 76% - 94% in FS, 4% - 21% in FT and 53% - 96% in KHN higher than Fuji II LC. For wear test, the experimental cements were only 5.4% - 13% of abrasive and 6.4% - 12% of attritional wear depths of Fuji II LC in each wear cycle. The one-month aging study also showed that all the experimental cements increased their CS continuously during 30 days, unlike Fuji II LC.

关键词： Poly(acrylic acid) Molecular Architecture Glass-Ionomer Cement Atom-Transfer Radical Polymerization Mechanical Strength

Experimental Investigation of Dielectric Barrier Discharge Using High Voltage Sub-microsecond Pulse Power in Atmospheric Air

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高电压技术 2013年第9期39卷 2280-2287页

作者： LI Jie xie Yutong dong Pan MA Bing WANG Liming ZHANG Linwen Key Laboratory of Pulsed Power Institute of Physics China Academy of Engineering Physics Mianyang 621900 China

An experimental device is used to study the characteristics of dielectric barrier discharge(DBD)plasma excited by high voltage sub-microsecond pulse power in atmospheric ***,polytetrafluoroethene(PTFE)and plexiglass are used as dielectric barrier *** homogeneous discharge is obtained within 130 mm diameter area in atmospheric air using the three dielectric materials with gap distances of 4.5 mm,6.5 mm and 6.5 mm,*** is no filamentary discharge observed by naked eyes or by camera with the exposure time of 0.25 *** gap voltage,discharge current,discharge power density,*** calculated by using Liu’s equivalent circuit model for pulsed *** parameters are used to study the DBD ***,current varies from tens of amperes to hundreds of amperes in atmospheric air DBD excited by sub-microsecond *** peak power can reach to MW order of *** average power surface density of 1.0 W/cm2and the average electron density of 1011cm 3can also be obtained in the *** and vibrational temperatures,approximately 400 K and 2 650 K,respectively,are obtained by using the emission spectrum of the *** is the basic work performed for a better understanding of the characteristics of atmospheric air DBD plasma excited by high voltage sub-microsecond pulsed power source.

关键词：介质阻挡放电脉冲高压电源实验装置大气微秒放电等离子体等效电路模型脉冲电源

汛期地铁行车荷载作用下越江隧道离散元分析（英文）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2018年第5期19卷 346-366页

作者： Zhi-hua ZHANG xie-dong ZHANG Yao TANG Yi-fei CUI School of Transportation Wuhan University of Technology Department of Civil and Environmental Engineering University of Alberta Department of Civil and Environmental Engineering Hong Kong University of Science and Technology

目的:揭示汛期及常水位条件下地铁随机振动荷载作用下越江隧道管片及周边岩土体的动力响应及变形机制。创新点:建立越江地铁隧道二维离散元模型,并采用随机振动荷载模拟地铁行车荷载,揭示汛期和常水位条件下地铁行车荷载对越江隧道稳定... 详细信息

目的:揭示汛期及常水位条件下地铁随机振动荷载作用下越江隧道管片及周边岩土体的动力响应及变形机制。创新点:建立越江地铁隧道二维离散元模型,并采用随机振动荷载模拟地铁行车荷载,揭示汛期和常水位条件下地铁行车荷载对越江隧道稳定性的影响。方法:采用离散元方法进行数值仿真。1.基于室内三轴试验和离散元数值拟合得到土层的各细观参数;2.采用不同接触模型对隧道内钢轨、轨枕、管片以及周边岩土体进行建模;3.将地铁随机振动荷载施加在钢轨上,对管片及周边岩土体不同区域内颗粒的受力及变形进行监测并分析。结论:1.位于隧道上半部分的周边岩土体颗粒振动偏大;2.随着距离的增大,振动波在周边岩土体内先放大后减小;3.汛期水位条件下地铁行车荷载对管片和周边岩土体的振动影响较小,但是对隧道变形影响较大。

关键词：离散元方法越江地铁隧道水压力地铁行车荷载

Algebraic Study of the Vibrational Levels and Potential Energy Surface of the Excited Electronic State （C^1A＇） for S2O

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Chinese Journal of Chemical Physics 2006年第1期19卷 43-46页

作者： Xiao-yan Wang Shi-liang Ding Jin-dong xie Peng-cheng Wang Wei-gang Zhong Department of RadioloEy Taishan Medical School Taian 271000 China School of Physics and Microelectronics Shandong University ji＇nan 250100 China

The vibrational levels and potential energy surface of a stable structure for S2O in the excited electronic states C^1A＇ were carried out with algebraic method. The vibrational spectra were obtained （with total quantum number v=20） by fitting 30 spectra data. The fitted rms（root mean square） error based on the Hamiltonian witb 9 parameters was 2.40 cm^-1. The dissociation energy and force constant were also determined by the analytical potential energy surface. The method is proved to be effective by comparing these results with the experimental data.

关键词： S2O3 Energy level Potential energy surface

A microporous surface containing Si3N4/Ta microparticles of PEKK exhibits both antibacterial and osteogenic activity for inducing cellular response and improving osseointegration

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Bioactive Materials 2021年第10期6卷 3136-3149页

作者： Xinglong Hu Shiqi Mei Fan Wang Songchao Tang dong xie Chao Ding Wenli Du Jun Zhao Lili Yang Zhaoying Wu Jie Wei Key Laboratory for Ultrafine Materials of Ministry of Education East China University of Science and TechnologyShanghai200237China Spine Center Department of OrthopaedicsShanghai Changzheng HospitalSecond Military Medical UniversityShanghai200003China Shanghai Key Laboratory of Stomatology Shanghai Research Institute of StomatologyDepartment of OrthodonticsNinth People’s Hospital Affiliated to Shanghai Jiao Tong UniversitySchool of MedicineShanghai200011China School of Biomedical Engineering Sun Yat-sen UniversityGuangzhouGuangdong510006China

As an implantable biomaterial,polyetherketoneketone(PEKK)exhibits good mechanical strength but it is biologically inert while tantalum(Ta)possesses outstanding osteogenic bioactivity but has a high density and elastic ***,silicon nitride(SN)has osteogenic and antibacterial *** this study,a microporous surface containing both SN and Ta microparticles on PEKK(STP)exhibiting excellent osteogenic and antibacterial activity was created by *** with sulfonated PEKK(SPK)without microparticles,the surface properties(roughness,surface energy,hydrophilicity and protein adsorption)of STP significantly increased due to the SN and Ta particles presence on the microporous *** addition,STP also exhibited outstanding antibacterial activity,which inhibited bacterial growth in vitro and prevented bacterial infection in vivo because of the presence of SN ***,the microporous surface of STP containing both SN and Ta particles remarkably induced response(e.g.,proliferation and differentiation)of rat bone mesenchymal stem(rBMS)cells in ***,STP significantly improved new bone regeneration and osseointegration in *** the induction of cellular response in vitro and improvement of osseointegration in vivo,the microporous surface containing Ta was better than the surface with SN *** conclusion,STP with optimized surface properties activated cellular responses in vitro,enhanced osseointegration and prevented infection in ***,STP possessed the dual biofunctions of excellent osteogenic and antibacterial activity,showing great potential as a bone substitute.

关键词： Silicon nitride Tantalum Polyetherketoneketone Antibacterial activity Osseointegration

Accurate calculation of the potential energy curve and spectroscopic parameters of X^2Σ^+ state of ^(12)Mg^1H

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Chinese Physics B 2015年第4期24卷 170-174页

作者：伍冬兰谭彬谢安东闫冰丁大军 Institute of Atomic and Molecular Physics Jilin University College of Mathematics and Physics Jinggangshan University Jilin Provincial Key Laboratory of Applied Atomic and Molecular Spectroscopy Jilin University

High level calculations on the ground state of 12Mg1H molecule have been performed using multi-reference configuration interaction （MRCI） method with the Davidson modification. The core-valence correlation and scalar relativistic corrections are included into the present calculations at the same time. The potential energy curve （PEC） of the ground state, all of the vibrational levels and spectroscopic parameters are fitted. The results show that the levels and spectroscopic parameters are in good agreement with the available experimental data. The analytical potential energy function （APEF） is also deduced from the calculated PEC using the Murrell-Sorbie （M-S） potential function. The present results can provide a helpful reference for the future spectroscopic experiments or dynamical calculations of the molecule.

关键词： multi-reference configuration interaction potential energy curve analytical potential energy function spectroscopic parameters