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二苯甲酮类多酚的糖基化衍生、活性评价及与PDIA6的相互作用

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药学学报 2024年第6期59卷 1706-1719页

作者：李蔷程宁宁冯秀娥李青山山西医科大学药学院山西太原030001 山西医科大学教育部慢性肾脏病医药基础研究创新中心山西太原030001 山西中医药大学基于炎性反应的重大疾病创新药物山西省重点实验室山西晋中030619

蛋白质二硫键异构酶A6(PDIA6)与炎症和内质网应激密切相关。为了获得靶向PDIA6且具有强抗炎作用的二苯甲酮类多酚糖基衍生物,本文以不同基团取代的二苯甲酮与α-溴代乙酰糖为起始原料,经傅克酰基化、脱乙酰基反应合成了25个目标糖基衍生... 详细信息

蛋白质二硫键异构酶A6(PDIA6)与炎症和内质网应激密切相关。为了获得靶向PDIA6且具有强抗炎作用的二苯甲酮类多酚糖基衍生物,本文以不同基团取代的二苯甲酮与α-溴代乙酰糖为起始原料,经傅克酰基化、脱乙酰基反应合成了25个目标糖基衍生物,并采用生物膜干涉(Bli)技术,定量研究其与PDIA6的相互作用,同时评价其体外抗炎作用。结果表明,化合物4b、10b、17b、18b、25b既与PDIA6有较高的亲和力,又具有很强的抗炎作用,这些化合物可能是通过直接作用于PDIA6,进而影响炎症相关的信号通路。尤其是,该类化合物对IL-1β和IL-6的抑制作用最为显著,推测其在治疗炎症性疾病方面有重要的开发前景。

关键词：二苯甲酮类多酚合成糖基化蛋白质二硫键异构酶A6 抗炎

荧光光谱法测定二苯甲酮类卤酚与血红素加氧酶-1的相互作用

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化学研究与应用 2024年第7期36卷 1568-1576页

作者：刘金帅宋婷冯秀娥李青山山西医科大学药学院山西太原030001 山西医科大学教育部慢性肾脏病医药基础研究创新中心山西太原030001 山西中医药大学基于炎性反应的重大疾病创新药物山西省重点实验室山西晋中030619

采用荧光光谱法,探讨三种具有强抗炎、抗氧化活性的二苯甲酮类卤酚3,4-二羟基-3'-氯二苯甲酮(LM46)、4,5-二羟基-2,3-二溴二苯甲酮(LM48)、2,4',5'-三羟基-5,2'-二溴二苯甲酮(LM49)与血红素加氧酶-1(HO-1)的相互作用机制,结合分子对接... 详细信息

采用荧光光谱法,探讨三种具有强抗炎、抗氧化活性的二苯甲酮类卤酚3,4-二羟基-3'-氯二苯甲酮(LM46)、4,5-二羟基-2,3-二溴二苯甲酮(LM48)、2,4',5'-三羟基-5,2'-二溴二苯甲酮(LM49)与血红素加氧酶-1(HO-1)的相互作用机制,结合分子对接分析其相互作用模式。在模拟生理条件下,用荧光猝灭法求得卤酚与蛋白配合物的结合常数,探讨主要作用力类型,并用同步、三维荧光光谱探讨其对HO-1蛋白构象的影响。荧光猝灭实验结果表明,随着温度的升高,LM46、LM48、LM49的猝灭常数(K_(sv))均下降,表观结合常数(K_(b))相应降低。卤酚与HO-1的相互作用发生荧光猝灭的机制属于静态猝灭。热力学数据表明,LM46、LM48和LM49与HO-1间的作用主要为范德华力、氢键或质子化等作用力,且反应可自发进行。同步荧光光谱、三维荧光光谱结果表明,卤酚与HO-1结合后,使HO-1的构象发生变化,进而影响色氨酸(Trp)或酪氨酸(Tyr)残基周围的微环境,改变HO-1腔内的疏水环境。

关键词：荧光光谱卤酚血红素加氧酶-1 相互作用分子对接

基于静态与动态学习需求感知的知识点推荐方法

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软件学报 2024年第9期35卷 4425-4447页

作者：周洋涛李青山褚华李佳楠高明彪卫彪彪西安电子科技大学计算机科学与技术学院陕西西安710071

随着互联网信息技术的高速发展,线上学习资源的爆炸式增长引起了“信息过载”与“学习迷航”问题.在缺乏专家指导的场景中,用户难以明确自己的学习需求并从海量的学习资源中选择合适的内容进行学习.教育领域推荐方法能够基于用户的历史... 详细信息

随着互联网信息技术的高速发展,线上学习资源的爆炸式增长引起了“信息过载”与“学习迷航”问题.在缺乏专家指导的场景中,用户难以明确自己的学习需求并从海量的学习资源中选择合适的内容进行学习.教育领域推荐方法能够基于用户的历史学习行为提供学习资源的个性化推荐,因此该方法近年来受到大量研究人员的广泛关注.然而,现有的教育领域推荐方法在学习需求感知时忽略了对知识点之间复杂关系的建模,同时缺乏考虑用户学习需求的动态性变化,导致推荐的学习资源不够精准.针对上述问题,提出一种基于静态与动态学习需求感知的知识点推荐方法,通过静态感知与动态感知相结合的方式建模复杂知识关联下的用户学习行为.对于静态学习需求感知,设计一种基于知识点先修后继元路径引导的注意力图卷积网络,通过建模知识点之间先修后继关系的复杂约束,能够消除其他非学习需求因素的干扰,从而精准地捕获用户在细粒度知识点层面上的静态学习需求;对于动态学习需求感知,所提方法以课程为单元聚合知识点嵌入以表征用户在不同时刻的知识水平,然后采用循环神经网络建模编码用户的知识水平序列,能够有效地挖掘用户知识水平变化中蕴含的动态学习需求;最后,对获得的静态与动态学习需求进行融合,在同一框架下建模静态与动态学习需求之间的兼容性,促进这两种学习需求相互补充,以实现细粒度的个性化知识点推荐.实验表明,在两个公开数据集上,所提方法能够有效地感知用户的学习需求并提供个性化的知识点推荐,在多种评估指标上优于主流的推荐方法.

关键词：知识点推荐知识感知动态性建模学习需求融合

Developing a risk assessment system for gas tunnel disasters in China

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Journal of Mountain Science 2017年第9期14卷 1751-1762页

作者： KANG Xiao-bing LUO Sheng li qing-shan XU Mo li Qiang State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology College of Engineering Sichuan Normal University

Gas disasters always restrict the tunnel constructions in mountain area, which becomes a major geological barrier against the development of underground engineering. China is rich in coal resources and has a large amount of gas with a wide range of distribution. However, China experienced not only adverse effects on coal mining but also gas disasters in underground engineering construction, such as tunnels and chambers. With the increased number of tunnels passing through coal-bearing strata, the incidence of gas accidents is also rising. Therefore, the significance of preventing and mitigating gas disasters should be emphasized, and an effective risk assessment method for gas disasters should be established. On the basis of research on over 100 gas tunnels in China, a relatively ideal gas disaster risk assessment method and system for tunnels are established through the following measures. Firstly, geo-environmental conditions and gas situations were analyzed during construction. Secondly, qualitative analysis was combined with quantitative analysis. Finally, the influencing factors of gas disasters, including geological conditions, gas,and human factors, were investigated. The gas tunnel risk assessment system includes three levels:(1) the grading assessment of a gas tunnel during the planning stage,(2) the risk assessment of gas tunnel construction during the design and construction stages,(3) the gas tunnel outburst risk assessment during the coal uncovering stage. This system was applied to the dynamic assessment of gas disaster during the construction of the Zipingpu tunnel of Dujiangyan–Wenchuan Highway(in Sichuan, Southwest China). The assessment results were consistent with the actual excavation, which verified the rationality and feasibility of the system. The developed system was believed to be back-up and applied for risk assessment of gas disaster in the underground engineering construction.

关键词： Tunnel engineering Gas disasters Risk assessment Index system Zipingpu tunnel

Purification and in vitro Activity of an Antimicrobial Peptide from Skin of Rana Temporaria Chensinensis,David

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Chemical Research in Chinese Universities 2007年第4期23卷 433-436页

作者： ZHOU Jie MENG qing-fan XU Xue-song TIAN Xiao-le JIANG Fu-jia li qing-shan TENG li-rong College of life Science Jilin University Changchun 130012 P. R. China Department of Laboratory China-Japan Union Hospital Jilin University Changchun 130033 P. R.China

In this study, an antimicrobial component（RTCI） was purified from the skin of Rana temporaria chensinensis, David. Antimicrobial activities of RTCI against clinical multi-drug resistant bacterial strains, including Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureaus, Klebsiella oxytoca, Klebsiella pneumoniae, Enterococcus fae-calis, and Proteus mirabilis, were measured in vitro by means of minimal inhibitory concentration and time-kill studies. The results indicate that RTCI could inhibit the growth of these bacteria at a proper concentration and suggest that RT-CI shows a better antimicrobial activity to Gram-negative bacterial strains than to Gram-positive bacterial strains.

关键词： Antimicrobial peptides Multi-drug resistant Amphibian skin

Synthesis and activities of new 4-hydroxybenzoxazolone derivatives

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Chinese Chemical Letters 2010年第1期21卷 63-66页

作者： Tang, li Ban, Shu Rong Feng, Xiu E. lin, Wen Han li, qing shan shanxi Med Univ Sch Pharmaceut Sci Taiyuan 030001 Peoples R China Peking Univ State Key Lab Nat & Biomimet Drugs Beijing 100083 Peoples R China

A series of new 4-substituted benzoxazolone derivatives were synthesized according to a convenient method,their anti-inflammatory and analgesic activities in vivo were *** of them were new compounds,the structures of all the synthesized compounds were confirmed by ~1H NMR,^(13)C NMR,ESI-MS and *** of the compounds exhibited anti-inflammatory activity.

关键词： Synthesis 4-Hydroxy benzoxazolone derivatives Anti-inflammatory activity

Syntheses of novel series benzo [1,5] oxazepin-4-one-based compounds from 1,5-difluoro-2,4-dinitrobenzene

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Chinese Chemical Letters 2008年第9期19卷 1021-1023页

作者： li Qiu Wang qing shan li Xin Pu Wei Wei Nie Xiao Fei Lv Qiu Rong li Yanshan University Qinhuangdao 066004 China

A novel benzo [ 1,5] oxazepin-4-one skeleton compound and its four derivatives were synthesized effectively from 1,5-difluoro- 2,4-dinitrobenzene （DFDNB） under mild conditions. In the process, four intermediates were synthesized by substitutions of the two fluorine atoms and reductions of the meta-dinitro groups in DFDNB respectively. The results showed that the key for synthesizing the intermediates was the substitution of one of the two fluorine atoms in DFDNB by 3-hydroxy butyric acid ethyl ester first, then the other fluorine atom by morpholine, and then the reduction of the meta-dinitro groups in the substitute by HCOONH4 with Pd/C. The products were purified with silica gel column chromatography, and confirmed by HPLC, LC-MS and 1H NMR. They should contribute to construct the molecular libraries for therapeutic applications.

关键词： Syntheses Benzo oxazepin derivatives DFDNB Substitution Reduction

FEM Analysis of Rolling Pressure Along Strip Width in Cold Rolling Process

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Journal of Iron and Steel Research International 2007年第5期14卷 22-26页

作者： liU Xiang-hua SHI Xu li shan-qing XU Jian-yong WANG Guo-dong State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China Research and Development Center Baoshan Iron and Steel Co Ltd Shanghai 201900 China Baosteel Branch Co Baoshan Iron and Steel Co Ltd Shanghai 201900 China

Using 3-D elastic-plastic FEM, the cold strip rolling process in a 4-high mill was simulated. The elastic deformation of rolls, the plastic deformation of the strip, and the pressure between the work roll and the backup roll were taken into account. The distribution of rolling pressure along the strip width was obtained. Based on the simulation results, the peak value of rolling pressure and the location of the peak were analyzed under different rolling conditions. The effects of the roll bending force and the strip width on the distribution of rolling pressure along the width direction were determined.

关键词： thin strip cold rolling elastic-plastic FEM pressure distribution

Synthesis and Anti-VSMC Vegetation Activities of New Aurone Derivatives

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Chemical Research in Chinese Universities 2012年第3期28卷 438-442页

作者： FAN Rui BAN Shu-rong FENG Xiu-e ZHAO Chen-xiao li qing-shan School of Pharmaceutical Science Shanxi Medical UniversityTaiyuan 030001P.R.China State Key Laboratory of Natural and Biomimetic Drugs Peking UniversityBeijing 100083P.R.China

A series of new aurone derivatives was prepared by means of a practical route and their anti-vascular smooth muscle cells（VSMC） vegetation activities were evaluated by the 3-（4,5-dimethylthlazol-2-yl）-2,5- diphenyltetrazolium bromide（MTT） method with tetrandrine as a positive contrast drug. The structures of the com- pounds were confirmed by 1H NMR, 13C NMR and electrospray ionization mass spectrometry（ESI-MS）. Several new compounds exhibited promising activity against VSMC proliferation and the preliminary structure-activity relation- ships（SAR） were discussed in order to investigate the essential structures required for their bioactivities.

关键词： Aurone derivative Anti-vascular smooth muscle cell(VSMC) vegetation activity Synthesis