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干细胞的趋电性迁移及机制

中国组织工程研究 2025年第23期29卷 4984-4992页

作者：韩芳舒晴贾绍辉田峻武汉体育学院运动医学院湖北省武汉市430079 武汉大学中南医院骨科康复科湖北省武汉市430071

背景:随着对干细胞技术研究的深入,如何使其准确归巢成为临床应用中的一大难题。除药物和趋化因子等信号的诱导外,电场也被广泛应用于指导干细胞的定向迁移,并可增强其迁移速度和定向性。目的:旨在分析总结电场对干细胞迁移特性的影响,... 详细信息

背景:随着对干细胞技术研究的深入,如何使其准确归巢成为临床应用中的一大难题。除药物和趋化因子等信号的诱导外,电场也被广泛应用于指导干细胞的定向迁移,并可增强其迁移速度和定向性。目的:旨在分析总结电场对干细胞迁移特性的影响,同时综述可能的作用机制。方法:通过检索Pub Med和中国知网数据库,收集截至2024年3月的相关文献,英文检索词:“stem cells,direct current electric field,pulsed electric field,migration,electric field device,mechanism”;中文检索词:“干细胞,直流电场,脉冲电场,迁移,电场装置,机制”。排除不能获取全文和与主题无关的文献。结果与结论:根据筛选要求共纳入58篇文献,包括中文文献15篇及英文文献43篇。文献以脂肪间充质干细胞、骨髓间充质干细胞、神经干细胞、表皮干细胞、人胚胎干细胞和人诱导性多功能干细胞为研究对象,在迁移装置中研究电场的不同参数对上述干细胞迁移的影响及其机制。(1)电场作为一种简单、无创且稳定的干预方式在指导干细胞定向迁移的过程中起着积极作用;(2)不同类型的干细胞发生趋电性迁移的方向不同,同时大部分干细胞的迁移速度和定向性是随着电场强度增加而增加的;(3)不同的电场装置在观测干细胞迁移时的侧重点不同,可根据实验目的而择优选择相关装置;(4)不同干细胞趋电性迁移的机制不完全相同,多数干细胞迁移过程中有MAPK通路、ROCK活化以及PI3K功能的参与,同时还有其他蛋白质复合物与信号通路参与调控该过程;(5)除电场参数不同之外,细胞本身的衰老情况和培养环境也会对趋电性迁移的结果产生影响。总而言之,电场作为一种影响干细胞迁移特性的重要信号,与其他新兴材料结合在组织工程应用中展现出了一定的潜力,有望在指导干细胞归巢方面发挥更加重要的作用,促进骨组织再生和修复以及神经系统、自身免疫系统以及肿瘤等疾病的研究取得更大的突破。

关键词：干细胞电场趋电性迁移机制归巢效应物理因子电场装置细胞衰老培养环境

湖南省1997～2005年不合格标本AFP病例专家诊断与分类研究

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实用预防医学 2006年第3期13卷 576-578页

作者：张淑君李放军李俊华王长江张红湖南省疾病预防控制中心湖南长沙410005

目的对湖南省1997-2005年不合格粪便标本（不合格标本）急性弛缓性麻痹（AFP）病例进行临床诊断与分类分析，提高AFP病例分类的准确性，为保持无脊灰状态提供科学依据。方法采用AFP病例病毒学分类法，由湖南省AFP病例分类专家诊断小... 详细信息

目的对湖南省1997-2005年不合格粪便标本（不合格标本）急性弛缓性麻痹（AFP）病例进行临床诊断与分类分析，提高AFP病例分类的准确性，为保持无脊灰状态提供科学依据。方法采用AFP病例病毒学分类法，由湖南省AFP病例分类专家诊断小组每年定期审查所有AFP病例，重点对不合格标本AFP病例进行临床分析与诊断，根据流行病学、临床诊断、实验室病原学监测结果等资料综合分析，作出最终分类。结果湖南省1997～2005年共报告2031例AFP病例，均为脊髓灰质炎（脊灰）排除病例。其中不合格标本AFP病例270例，经诊断，主要病种为创伤性神经炎（26．7％）、格林巴利综合征（16．3％）、脑病（8．9％）、非脊灰肠道病毒感染（4．8％）等。结论 AFP病例分类结果证明湖南省1997～2005年未发现脊灰野病毒病例，不合格标本AFP病例的临床诊断和最终分类结果为湖南省继续保持无脊灰状态提供重要依据。

关键词：急性弛缓性麻痹不合格标本病例专家诊断病例分类

Detailed structural,mechanical,and electronic study of five structures for CaF2 under high pressure

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Chinese Physics B 2021年第3期30卷 194-204页

作者： Ying Guo Yumeng fang jun li Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology Jiangsu Key Laboratory of Big Data Analysis TechnologyNanjing University of Information Science and TechnologyNanjing 210044China Mingde New Material Technology Co. LTDAnji 313300China

Detailed density functional theory(DFT)calculations of the structural,mechanical,thermodynamic,and electronicproperties of crystalline CaF2 with five different structures in the pressure range of 0 GPa–150 GPa are performed byboth GGA(generalized gradient approximation)-PBE(Perdew–Burke–Ernzerhof)and LDA(local density approximation)-CAPZ(Cambridge Serial Total Energy Package).It is found that the enthalpy differences imply that the fluorite phase→PbCl2-type phase→Ni2In-type phase transition in CaF2 occurs at PGGA1=8.0 GPa,PGGA2=111.4 GPa by usingthe XC of GGA,and PLDA1=4.5 GPa,PLDA2=101.7 GPa by LDA,respectively,which is consistent with previousexperiments and theoretical ***,the enthalpy differences between PbCl2-type and Ni2In-type phases inone molecular formula become very small at the pressure of about 100 GPa,indicating the possibility of coexistence of twophase at high *** may be the reason why the transition pressure of the second phase transition in other reportsis so huge(68 GPa–278 GPa).The volume changed in the second phase transition are also consistent with the enthalpydifference ***,the pressure dependence of mechanical and thermodynamic properties of CaF2 is *** found that the high-pressure phase of Ni2In-type structure has better stiffness in CaF2 crystal,and the hardness of thematerial has hardly changed in the second phase ***,the electronic structure of CaF2 is also analyzed withthe change of *** analyzing the band gap and density of states,the large band gap indicates the CaF2 crystal isalways an insulator at 0 GPa–150 GPa.

关键词： density functional theory(DFT) high-pressure phase transition coexistence

Applicability of anoxic-oxic process in treating petrochemical wastewater

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第1期10卷 133-141页

作者： li-jun ZHAO fang MA Jing-bo GUO School of Chemical Engineering China University of Petroleum Beijing 102249 China School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150090 China

To explore the applicability of anoxic-oxic (A/O) activated sludge process for petrochemical wastewater treatment,the relationship between bacterial community structure and pollutants loading/removal efficiencies was investigated by gas chromatograph-mass spectrometry (GC-MS),polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) and other conventional *** showed that when the concentrations of the influent chemical oxygen demand (COD) and ammonia nitrogen (NH4+-N) were 420～560mg/L and 64～100mg/L,respectively,the corresponding average effluent concentra-tions were 160mg/L and 55mg/L,which were 1.6 and 2.2times higher than those of the national standards in China,respectively,demonstrating the inefficient performances of A/O *** of GC-MS indicated that refractory pollutants were mainly removed by sludge adsorption,but not by ***-DGGE profile analysis suggested that the biological system was species-rich,but there was apparent succession of the bacterial community structure in different locations of the A/O *** of bacterial community structure and pollutant loadings had obvious influences on pollutants removal ***,A/O process was inapplicable for the treatment of complicated petrochemical wastewater,and strategies such as the reinforcement of pre-treatment and two-stage A/O process were suggested.

关键词： Petrochemical wastewater Polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) Anoxic-oxic (A/O) process Applicability

Selective separation of silica from a siliceous-calcareous phosphate rock

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Mining Science and Technology 2011年第1期21卷 135-139页

作者： Guo fang li jun College of Chemical Engineering Sichuan University Chengdu 610065. China

Selective separation of silica from a siliceous-calcareous phosphate ore that had been sieved into different size fractions is investigated by a combination of chemical analysis,zeta potential measurement and FTIR and XPS *** is a better choice than flotation for removing silica from the coarse *** P_2O_5 grade of the coarse fractions is increased to about 30%by scrubbing and the product yields are higher than those obtained by *** silica in the fine fraction is separated by reverse *** alkyl amine salt(DAH)is an effective collector and the P_2O_5 grade of the fine fraction can be increased by 7%to beyond 30%under acidic *** higher zeta potential obtained using DAH suggests that it is more strongly absorbed onto the ore particles than the other cationic collectors. FTIR and XPS results confirm physical absorption of the cationic collector onto the ore *** also indicate that calcite is dissolved at low pH values,which increases the Si concentration on the ore surface.

关键词： Siliceous-calcareous phosphate rock Silica separation Reverse flotation Calcite gangue

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住院患者院内急救体系设计及效果评价

医院管理论坛 2017年第9期34卷 32-36页

作者：房君虞立王春英陈瑜刘鹏宁波市第二医院

目的建立一套新型院内快速急救体系,降低院内普通病房患者心跳呼吸骤停发生率。方法在成立急救医疗小组基础上实行改良早期预警评分系统,设置呼叫流程,成立快速反应小组,运行RRT联合MET急救模式等措施。结果 RRT联合MET急救模式运行前... 详细信息

目的建立一套新型院内快速急救体系,降低院内普通病房患者心跳呼吸骤停发生率。方法在成立急救医疗小组基础上实行改良早期预警评分系统,设置呼叫流程,成立快速反应小组,运行RRT联合MET急救模式等措施。结果 RRT联合MET急救模式运行前后一年内,普通病房患者心跳呼吸骤停发生率明显下降,减少了由意外猝死等引起的医疗纠纷,差异有统计学意义(P<0.05)。结论运行RRT联合MET的院内急救模式有助于提高普通病房医护人员对住院患者临床指标恶化的辨别和反应能力,降低心跳骤停和猝死等恶性事件的发生,减少医疗纠纷。

关键词：快速反应小组急救体系院内改良早期预警评分系统

Deciphering fungal metabolon coupling tandem inverse-electrondemand Diels-Alder reaction and semipinacol rearrangement for the biosynthesis of spiro polycyclic alkaloids

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Science China Chemistry 2025年第1期68卷 288-296页

作者： Shuai liu Wen-Qiang Xu Ying-Tong Di Man-Cheng Tang Ding-Kang Chen Ming-Ming Cao Yao-Wen Chang Hong-Yu Tang Chun-Mao Yuan jun-Bo Yang Zhi-li Zuo Han Guo Zi-Fei Xu Ying Zeng Yun-Dong Wu Xiao-Jiang Hao Key Laboratory of Phytochemistry and Natural Medicines (Chinese Academy of Sciences) Kunming Institute of Botany Chinese Academy of Sciences University of Chinese Academy of Sciences Lab of Computational Chemistry and Drug Design State Key Laboratory of Chemical Oncogenomics Peking University Shenzhen Graduate School Shenzhen Bay Laboratory State Key Laboratory of Microbial Metabolism School of Life Sciences & Biotechnology Shanghai Jiao Tong University State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical University Molecular Biology Experimental Center Germplasm Bank of Wild Species in Southwest China Kunming Institute of Botany Chinese Academy of Sciences Yunnan Key Laboratory for Wild Plant Resources Kunming Institute of Botany Chinese Academy of Sciences Research Unit of Chemical Biology of Natural Anti-Virus Products Chinese Academy of Medical Sciences

In the intricate process of natural product biosynthesis, a metabolon can enhance metabolic flux by associating sequential enzymes. A fungal metabolon, comprising of flavin-dependent monooxygenase Spe F and P450 monooxygenase Spe G, is identified in the biosynthesis of spiro polycyclic alkaloids(+)-notoamide B and its diastereomer(+)-versicolamide B. Using notoamide E as a substance, Spe F/Spe G metabolon can control the stereoselectivity of its 2,3-epoxidation, followed by hydrogen atom ion at C-17 to generate reactive epoxide tau-m A with dienyl iminium unit. Subsequently,(+)-notoamide B and(+)-versicolamide B are produced via tandem nonenzymatic inverse-electron-demand Diels-Alder reaction and semipinacol rearrangement. This provides the first example of metabolon in the biosynthesis of spiro-prenylated indole alkaloids.

关键词： metabolon Diels-Alder reaction semipinacol rearrangement biosynthesis notoamides spiro polycyclic alkaloids

Non-thermal emission from Vela X and PWN G0.9+0.1

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Chinese Journal of Astronomy and Astrophysics 2009年第4期9卷 449-456页

作者： Wei-Fan Qiao li Zhang jun fang Department of Physics Yunnan University Kunming 650091 China

We study the multi-waveband non-thermal emission from the pulsar wind nebulae （PWNe） Vela X and G0.9＋0.1 in the frame of a time-dependent model describing non-thermal radiation from the PWNe. In such a model, the relativistic wind of particles driven by a central pulsar blows into the ambient medium and creates a termination shock that accelerates the particles to very high energy in a PWN. The non-thermal photons in the PWN are produced both by synchrotron radiation and the inverse Compton process, with electrons coming directly from the pulsar magnetosphere and electrons being accelerated at the termination shock. We apply this model to reproduce the observed multi-waveband photon spectra of Vela X and the G0.9＋0.1, both of which have been detected emitting very high energy photons. Our results indicate that TeV photons are produced by the inverse Compton scattering of the high-energy electrons in the infrared photon field in both Vela X and PWN G0.9＋0.1. The TeV photons from these two PWNe may have leptonic origins.

关键词： ISM individual objects Vela X, G0.9 + 0.1-gamma-rays theory

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双针-板结构脉冲气泡放电等离子体固氮研究

原子与分子物理学报 2025年第6期42卷 122-128页

作者：赵少伟张丽方志南京工业大学电气工程与控制科学学院南京211816

大气压低温等离子体可以利用空气直接进行氧化固氮,具有反应条件温和、参数灵活可控、避免温室气体排放等优点.本文利用双针-板电极在水中形成气泡放电等离子体,以空气为放电气体进行了固氮研究,分析了产物浓度和固氮能耗的影响因素.研... 详细信息

大气压低温等离子体可以利用空气直接进行氧化固氮,具有反应条件温和、参数灵活可控、避免温室气体排放等优点.本文利用双针-板电极在水中形成气泡放电等离子体,以空气为放电气体进行了固氮研究,分析了产物浓度和固氮能耗的影响因素.研究结果表明,等离子体中含有丰富的氮原子、氧原子、氢原子、激发态氮分子等活性物种,可高效合成硝态含氮产物.研究发现,脉冲参数、电极间隙、工作气体组分对气泡放电等离子体的固氮性能有重要影响.装置最高NO~-_x合成速率为19.2μmol/min,最小能耗约为11 MJ/mol.此外还发现,电极间隙为6 mm时,固氮性能最优;空气中增加适量氧气(氧气/氮气比例为0.4)可以增强产物合成,降低能耗.

关键词：低温等离子体纳秒脉冲放电气液放电固氮