Urotensin Ⅱ increases endothelin production by vascular smooth muscle cells in rats

The aim of this study was to observe the effects of urotensin Ⅱ (UII) on production of endothelin (ET) in rat aortic vascular smooth muscle cells (VSMC). Cultured VSMCs incubated with various concentrations of UII were used to measure the VSMC ³H-TdR incorporation, the amount of ET mRNA and ET production in VSMCs. In this work we found that UII (10^-10—10^-8 mol/L) promoted VSMC ³H-TdR incorporation (47%—83%, P < 0.01) and increased the amount of ET mRNA by 17.1% (P < 0.05) to 112.8% (P < 0.01), respectively, in a concentration dependent manner compared with control. After 4 and 8 h incubation, 10^-10—10^-8 mol/L of UII elevated the ET synthesis and release in a concentration dependent manner. After 4 h incubation, the content of ET in medium was 4.9, 5.36 and 7.12 pg/mL (P < 0.01). After 8 h incubation, the ET content released from VSMCs was 12.6, 12.07 and 17.17 pg/mL (P < 0.01). In addition, it was found that BQ₁₂₃, a specific ET_A receptor antagonist, obviously decreased the VSMC DNA synthesis induced by UII. The results of this study showed that UII could stimulate the ET mRNA expression and ET production in VSMC. The effects of UII on VSMC DNA synthesis were partly mediated by ET autocrine pathway. It suggests that the interaction between UII and ET plays an important biological regulating role as endogenous active peptides.     

Adrenomedullin inhibits the endothelin production in-duced by urotensin Ⅱ in rat vascular smooth muscle cells

The aim of this study was to observe the effects of adrenomedullin (ADM) on endothelin (ET) production induced by urotensin Ⅱ (UⅡ) in rat vascular smooth muscle cells (VSMCs). Cultured VSMCs which were incubated with UⅡ (10-8 mol/L) and with various concentrations of ADM were used to measure the VSMCs 3H-TdR incorpora-tion, the activity of extracellular signal-regulated kinase(ERK), the amount of ET mRNA and ET production inVSMCs. In this work we found that incubation with UⅡ(10-8 mol/L) increased obviously the amount of ET mRNA inVSMCs and ET production in medium, however,co-incubation with ADM (10-10-10-8 mol/L) and UⅡ(10-8mol/L) reduced the amount of ET mRNA by 15%, 24% and45% (P< 0.01) respectively, compared with UⅡ alone. Thecontent of ET in medium was 14.13, 11.38 and 11.00 pg/mL. ADM alone (10-8 mol/L) had no effect on ET production inVSMCs. UⅡ (10-8 mol/L) promoted the 3H-TdR incorpo-ration and activity of ERK in VSMCs. ADM inhibited VSMCs 3H-TdR incorporation and activation of ERK in aconcentration-dependent manner. Compared with UⅡgroup, after co-incubation with ADM (10-10-10-8 mol/L)and UⅡ (10-8 mol/L) the VSMCs 3H-TdR incorporation wasdecreased by 7% (P > 0.05), 32% (P < 0.05) and 41% (P <0.01), respectively, and the activity of ERK was decreasedby 24% (P > 0.05), 32% (P < 0.05) and 36% (P < 0.05), re-spectively, in a concentration-dependent manner. The resultsshow that in cultured VSMCs ADM inhibits ET mRNA ex-pression, ET production and proliferation stimulated by UⅡ, and that inhibitory effect of ADM on UⅡ bioaction could be mediated through inhibiting MAPK pathway.     

Urotensin Ⅱ increases endothelin production by vascular smooth muscle cells in rats

The aim of this study was to observe the effects of urotensin Ⅱ (UII) on production of endothelin (ET) in rat aortic vascular smooth muscle cells (VSMC). Cultured VSMCs incubated with various concentrations of UII were used to measure the VSMC 3H-TdR incorporation, the amount of ET mRNA and ET production in VSMCs. In this work we found that UII (10-10-10-8 mol/L) promoted VSMC 3H-TdR incorporation (47%-83%, P < 0.01) and increased the amount of ET mRNA by 17.1% (P < 0.05) to 112.8% (P < 0.01), respectively, in a concentration dependent manner compared with control. After 4 and 8 h incubation, 10-10-10-8 mol/L of UII elevated the ET synthesis and release in a concentration dependent manner. After 4 h incubation, the content of ET in medium was 4.9, 5.36 and 7.12 pg/mL (P < 0.01). After 8 h incubation, the ET content released from VSMCs was 12.6, 12.07 and 17.17 pg/mL (P < 0.01). In addition, it was found that BQ123, a specific ETA receptor antagonist, obviously decreased the VSMC DNA synthesis induced by UII. The results of this study showed that UII could stimulate the ET mRNA expression and ET production in VSMC. The effects of UII on VSMC DNA synthesis were partly mediated by ET autocrine pathway. It suggests that the interaction between UII and ET plays an important biological regulating role as endogenous active peptides.     

含水乙腈萃取精馏分离丙烷/丙烯的新工艺

对乙烯生产工艺中丙烷和丙烯的分离进行了研究 ,提出以含水乙腈为萃取剂的萃取精馏新工艺。选择合适的汽液平衡模型 ,利用 PRO/ II软件对原有工艺和新工艺进行模拟计算 ,计算结果表明这种新工艺具有显著的优越性。在此基础上对原有工艺和新工艺精馏塔板进行设计 ,塔板选用近年来广泛应用的新型多溢流复合斜孔塔板。新工艺对于丙烷和丙烯的精馏分离有一定的工业意义。     

运动对内皮素分泌影响的分析与研究

运动作为一种特殊刺激会引起机体内皮细胞分泌水平发生改变．该文总结人们研究的不同运动形式、不同运动强度及运动训练对内皮素分泌的影响,旨在促进运动对内皮素分泌的影响的研究,并为在运动训练中,探索合理的运动强度和运动时间,提高运动成绩,防止运动性疾病产生提供科学的依据。     

不同物种间胰岛素及其编码mRNA,DNA序列比较与分析

通过PSI-BLAST搜索与人类胰岛素原(含有86个氨基酸)相似的蛋白质序列，并进行比对，计算比对矩阵的相似得分和期望值，同时运用ClustalW算法对不同物种编码前胰岛素原mRNA及其翻译的蛋白质和DNA序列进行多重比对．结果发现，脊椎动物的胰岛素蛋白质一级结构(A链和B链)和mRNA非常相似，但部分动物C肽的部分序列有差异；系统进化分析表明，人和猴、小鼠和大鼠编码胰岛素的mRNA在进化上关系相近．各物种间编码相同氨基酸的核苷酸序列（CDS)相同，但编码胰岛素的DNA序列不同．各物种胰岛素原蛋白质序列中，A链和B链序列保守，C肽有一定的差异；DNA序列差异较大．     

一个多ON基因系统的表达动力学分析

研究了一个转录水平上的基因表达模型,它不仅考虑了启动子的复杂性,而且考虑了相互作用转录因子的调控效果.假定启动子区域有2个调控位点,启动子有1个失活态和2个激活态(即2个不同的转录出口),并考虑了绑定到不同调控位点的转录因子之间相互作用的3种代表性机制:招募机制,稳定机制和混合机制.理论分析和数值模拟结果显示:不同的转录出口能够导致mRNA分布峰的多样性; 3种机制下的平均表达水平和平均爆发频率都相同,但稳定机制诱导最大的表达噪声和平均爆发规模,而招募机制诱导最小的表达噪声和平均爆发规模.这些结果表明:细胞表型的产生源是复杂的,既与启动子结构有关也与调控机制有关.     

蛋白质二级结构由氨基酸和mRNA序列编码

据氨基酸序列,密码子序列和蛋白质二级结构序列的比较,指出约18％的两肽的密切子具有反常的蛋白质结构偏好性,并且这种以常不能用随机涨落解释,因而关于蛋白质折迭的Anfinsen原理可能需要作适当修正。     

运动训练与内皮素

内皮素对人体具有广泛的生物学效应.简要介绍了内皮素的生物学功能,并从不同方式运动对内皮素分泌的影响、运动影响心血管系统内皮素分泌的机制及内皮素对运动时心血管系统的作用等几个方面进行综述.     

改善记忆中草药与核桃肽的相互作用

选取五种传统具有改善记忆作用的中草药（人参、远志、茯苓、龙眼及银杏叶）,分别水提得到相应的活性成分,并与核桃多肽进行相互作用后研究复合物的理化特性与抗氧化活性。通过含量和抗氧化测定,发现所提取的中草药活性物质均具有抗氧化、清除自由基功效。以蛋白回收率和抗氧化活性为指标优化核桃酶解工艺,并分析最佳酶解液的总氨基酸组成,并借助抗氧化性评价和荧光光谱法,研究中草药活性物质与核桃多肽的交互作用,探讨不同相互作用条件（如,配比、温度、pH等）对交互作用的影响。结果表明,中草药中提取的目标活性物质使核桃多肽荧光发生猝灭,表明两类物质发生交互作用,且在抗氧化功效上有协同作用。通过对交相互作用影响因素的探讨,发现合适的配比更利于协同效果,温度、pH值对多糖和多肽交相互作用的影响较为显著。该发现可为相关产品生产时中草药活性物质与多肽类物质的复配提供一定的参考意义。     

多过程故障发现及监控支持系统

本文对自动化生产过程的故障发现问题进行了研究,建立了系统监控的多过程故障发现模型,并通过实验验证了模型的有效性及考虑了参数选择问题。以该模型为基础,本文提出了一种以图形方式进行人机交互的故障发现决策方法,并开发了相应的监控支持系统。该模型及监控支持系统具有结构简单、活动参数少、实用化强的特点。仿真实验结果表明,采用监控支持系统后,监控者对系统中典型故障的发现时间平均可减少约19%。     

基于网络的多媒体课件的交互设计与实现

基于网络的多媒体课件必须具备交互性的特点，以实现学生与计算机、教师与学生的交互功能，探讨了课件人机交互、教学交互的几种交互方式的设计思路和制作方法，并阐述了基于WEB的B／S模式体系结构的课件设计技术。     

基于VRML的3D人—人交互界面的研究与实现

提出用 Ｖ Ｒ Ｍ Ｌ 技术实现 Ｃ Ｓ Ｃ Ｗ 系统中的３ Ｄ 人—人交互界面, 论述了基于 Ｖ Ｒ Ｍ Ｌ 的３ Ｄ 人—人交互界面的基本特性、实现方法及其通用性这种基于 Ｖ Ｒ Ｍ Ｌ 的３ Ｄ 人—人交互界面,较２ Ｄ 人—人交互界面,能为群体提供更丰富的协作信息,尤其是协作者身体活动的状态信息,使群体人员能更直观、更自然地交互;它实现了虚拟现实的效果,又可以不需要虚拟现实设备的支持,且与平台无关;它包含了２ Ｄ 界面和３ Ｄ 界面,两者可相互通信,协调工作,适用于需要集成２ Ｄ 和３ Ｄ 界面的 Ｃ Ｓ Ｃ Ｗ 系统,具有较广的通用性利用 Ｖ Ｒ Ｍ Ｌ 技术来构造 Ｃ Ｓ Ｃ Ｗ 系统中的３ Ｄ 人—人交互界,可以大大缩短系统的研究和开发周期     

甲基丙烯酸酯类毛细管整体柱分离极性物质的研究

以甲基丙烯酸缩水甘油酯、甲基丙烯酸、2-二甲基乙基胺甲基丙烯酸酯为单体,乙二醇二甲基丙烯酸酯为交联剂．偶氮二异丁腈为引发剂,十二醇和环己醇为二元致孔剂,原位聚合制备了聚（甲基丙烯酸缩水甘油酯-乙二醇二甲基丙烯酸酯-2-二甲基乙基胺甲基丙烯酸酯-甲基丙烯酸）毛细管液相色谱整体柱．然后在酸性条件下,对甲基丙烯酸缩水甘油酯的环氧环进行开环反应生成二醇。增加了固定相表厩的极性．通过简单的改变流动相乙腈浓度,分析过程表现为不同的作用机理．在高乙腈浓度下为典型的亲水作用机理．对于带电物质,固定相与分析物间的静电作用也对保留起到一定作用,为极性组分分离提供更多的选择条件．     

Dark current mechanism of unpassivated mid wavelength type II InAs/GaSb superlattice infrared photodetector

We investigate the dark current mechanism for an unpassivated mid wavelength(MW) type II InAs/GaSb superlattice infrared photodetector by doing the variablearea diode tests. The bulk resistance-area product and the resistivity due to the surface current are determined to be17.72 X cm2 and 704.23 X cm at 77 K, respectively. It is found that for all the mesa sizes used, the dark current is dominated or predominated by the surface component, and with scaling back the mesa size, the surface current increases while the bulk component decreases. The activation energy is determined to be 145 meV for the temperature range around 140–280 K, while it is 6 meV when temperature is below 100 K. It is also found that the dark current is dominated by the generation-recombination current for the MW device when temperature is between140 and 280 K.     

迷向周期和方法在β-簮结构折褶模拟中的应用

采用新近提出的迷向周期和方法(IPS),结合自导Lang evin动态模拟,模拟研究9余肽折褶成β簮结构的情况,表明了该结构与NMR观察到的基本一致,而Ewald模拟由于是强烈的镜像相互作用会产生构型偏差,获得致密构型的几率增大,表明IPS方法更适合于周期边界条件的模拟.     

川芎嗪治疗老年人肺动脉高压及其与内皮素的关系

目的:探讨川芎嗪对老年人肺动脉高压的治疗作用与内皮素的关系.方法:采用右心导管直接监测肺动脉压力,观察静脉注射川芎嗪前、注射后20 min、注射后45 min肺动脉平均压力(mPAP)变化及血浆内皮素(ET)水平的变化.结果:静脉注射川芎嗪前、注射后20 min、注射后45 min mPAP分别为(3.6±0.3)kPa,(2.7±0.19)kPa,(2.9±0.1)kPa,血浆ET质量浓度分别为(60.7±13.5)pg/mL、(25.1±12.2)pg/mL、(28.3±12.8)pg/mL,注射后20 min、注射后45 min mPAP、ET分别与静脉注射川芎嗪前比较有显著性差异(P＜0.01).结论:抑制内皮素的合成、分泌可能是川芎嗪治疗老年人肺动脉高压的重要机制之一.