Extended state observer based smooth switching control for tilt-rotor aircraft

A tilt-rotor aircraft has three flight modes: helicopter mode, airplane mode and conversion mode. Unlike the traditional aircraft, the tilt-rotor aircraft, which combines the characteristics of helicopters and fixed-wing aircraft, is a complex multi-body system with the violent variation of the aerodynamic parameters. For these characteristics, a new smooth switching control scheme is provided for the tilt-rotor aircraft. First, the reference commands for airspeed and nacelle angles are calculated by analyzing the conversion corridor and the conversion path. Subsequently, based on the finite-time switching theorem, an average dwell time condition is designed to guarantee the stability in the switching process. Besides, considering the state vibrations and bumps may appear in switching points, the fuzzy weighted logic is employed to improve the system transient performance. For disturbance rejection, three extended state observers are designed separately to estimate the disturbances in the switched systems. Compared with the traditional auto disturbance rejection control and proportion integration differentiation control, this method overcomes the conservatism of wasting the whole model information. The control performances of robustness and smoothness are verified with simulation, which shows that the new smooth switching control scheme is more targeted and superior than the traditional design method.

Semaphorin 7A promotes human vascular smooth muscle cell proliferation and migration through theβ-catenin signaling pathway

Background:Vascular smooth muscle cells(VSMCs)undergo a conversion from a contractile phenotype to a proliferative synthetic phenotype,contributing to the pathogenesis of cardiovascular diseases.Semaphorin 7A(SEMA7A)is a glycosylphosphatidylinositol-anchored membrane protein that plays an important role in vascular homeostasis by regulating endothelial cell behaviors.However,the expression and role of SEMA7A in VSMCs remain unclear.Methods:In this study,we screened for VSMC-regulating genes in publicly available datasets and analyzed the expression of SEMA7A in human coronary artery smooth muscle cells(hCASMCs)treated with platelet-derived growth factor-BB(PDGF-BB).The effects of SEMA7A overexpression and knockdown on hCASMC proliferation and migration were examined.The signaling pathways involved in the action of SEMA7A in hCASMCs were determined.Results:Bioinformatic analysis showed that SEMA7A was significantly dysregulated in VSMCs treated with oxidized low-density lipoprotein or overexpressing progerin,a pro-atherogenic gene.The PDGF-BB stimulation led to a concentration-and time-dependent induction of SEMA7A.Depletion of SEMA7A attenuated PDGF-BB-induced hCASMC proliferation and migration.Conversely,overexpression of SEMA7A enhanced hCASMC proliferation and migration.Mechanistically,SEMA7A stimulated the activation of theβ-catenin pathway and upregulated c-Myc,CCND1,and MMP7.Knockdown ofβ-catenin impaired SEMA7A-induced hCASMC proliferation and migration.Conclusions:SEMA7A triggers phenotype switching in VSMCs through theβ-catenin signaling pathway and may serve as a potential therapeutic target for cardiovascular diseases.

All-optical switching and nonlinear optical properties of HBT in ethanol solution

This paper demonstrates an all-optical switching model system comprising a single pulsed pump beam at 355 nm and a CW He-Ne signal beam at 632.8 nm with 2-（2＇-hydroxyphenyl）benzothiazole （HBT） in ethanol solution. The origins of the optical switching effect were discussed. By the study of nonlinear optical properties for HBT in ethanol solvent, this paper verified that the excited-state intramolecular proton transfer （ESIPT） effect of HBT and the thermal effect of solvent worked on quite different time scales and together induced the change of the refractive index of HBT solution, leading to the signal beam deflection. The results indicated that the HBT molecule could be an excellent candidate for high-speed and high-sensitive optical switching devices.

Highly reliable bipolar resistive switching in sol-gel derived lanthanum-doped PbTiO_3 thin film: Coupling with ferroelectricity?

Nanoscale PbxLa1-,Ti1-x/4O3 （PLT） thin film has been fabricated on Pt／Ti／SiO2／Si substrates by chemical solution deposition （CSD） method. Ferroelectricity of the fresh-made PLT thin film has been clearly detected through piezoelectric force microscopy （PFM） by writing reversible ferroelectric domains. However, PLT thin film also shows off-standard ferroelectric hysteresis loops highly dependent on frequency, indicating large amount of mobile space charges in the film. Subsequent current-voltage （C-V） studies show that sandwich-like Pt／PLT／Pt structure exhibits notable bipolar resistive switching （BRS） characteristics with high stability （〉 103 switching cycles）. It is found that the C-V curves of both high- and low-resistance states have the feature of space-charge-limited current （SCLC） conduction, indicating important roles of defects in the conduction. X-ray photoelectron spectroscopy measurement further verifies that oxygen vacancies based conductive filament mechanism is likely responsible for the observed RS effect. Our demonstration of stable RS effect in the PLT thin film and its possible coupling with ferroelectricity is promising in device development and applications, such as development of ferroelectric-tunable RS memories.

Improvement on Switching Characteristics and Switching Losses of IGBT by ZVS-PWM

Absrtact: The principle of ZVS - PWM inverting circuit is first described by means of inverting welder supply. The contrastive study is made on switching characte -ristics and switching losses of IGBT between ZVS - PWM and hard - switching.

内含子源性27nt-microRNA对大鼠血管平滑肌细胞表型转换的影响及其机制研究

目的 探讨内含子源性27nt-miRNA(27nt-miR)对血小板源性生长因子-BB(PDGF-BB)诱导大鼠血管平滑肌细胞(VSMCs)表型转换的影响及其分子机制。方法 用27nt-miR表达慢病毒转染培养的VSMCs,观察其对PDGF-BB诱导的VSMCs表型转换的影响;将细胞分为对照组、PDGF-BB诱导组、27ntmiR组、27nt-miR-sponge组及27nt-miR NC组(27nt-miR NC组)。雷帕霉素(100 nmol/L)与MHY-1485(10μmol/L)作用于27nt-miR组、27nt-miR-sponge组及27nt-miR NC组,以验证27nt-miR是否参与mTOR与p70S6k通路的调控。用生物信息学预测27nt-miR与mTOR的靶向结合位点,用CCK-8法与EdU法分别测定VSMCs活力与增殖情况,划痕试验测定VSMCs迁移能力,实时荧光聚合酶链反应检测α-SMA、SM22α及OPN mRNA表达,Western blotting检测α-SMA、SM22α、OPN、mTOR、p-mTOR、p70S6k与pp70S6k蛋白表达。结果 CCK-8法结果示,PDGF-BB诱导组细胞增殖率较正常值高(P <0.05),27ntmiR NC组与PDGF-BB诱导组比较,差异无统计学意义(P>0.05);27nt-miR组细胞增殖率较27nt-miR NC组低(P <0.05),27nt-miR-sponge组与27nt-miR NC组比较,差异无统计学意义(P>0.05)。PDGFBB诱导组细胞迁移率较对照组高(P <0.05),27nt-miR NC组与PDGF-BB诱导组比较,差异无统计学意义(P>0.05);27nt-miR组细胞迁移率较27nt-miR NC组低(P <0.05),27nt-miR-sponge组细胞迁移率与27nt-miR NC组比较,差异无统计学意义(P>0.05)。EdU法结果示,PDGF-BB诱导组细胞增殖率较对照组高(P <0.05),27nt-miR NC组与PDGF-BB诱导组细胞增殖率比较,差异无统计学意义(P>0.05);27nt-miR组细胞增殖率较27nt-miR NC组低(P <0.05),27nt-miR-sponge组与27nt-miR NC组比较,差异无统计学意义(P>0.05)。PDGF-BB诱导组α-SMA mRNA相对表达量较对照组低(P <0.05),两组SM22α与OPN mRNA相对表达量比较,差异无统计学意义(P>0.05)。27nt-miR NC组与PDGF-BB诱导组α-SMA、SM22α、OPN mRNA相对表达量比较,差异无统计学意义(P>0.05);27nt-miR组α-SMA、SM22α mRNA相对表达量较27nt-miR NC组高(P <0.05),OPN mRNA相对表达量较27nt-miR NC组低(P <0.05);27nt-miR-sponge组与27nt-miR NC组α-SMA、SM22α mRNA相对表达量比较,差异均无统计学意义(P>0.05),27nt-miR-sponge组OPNm RNA相对表达量较27nt-miRNC组高(P<0.05)。PDGF-BB诱导组α-SMA、SM22α蛋白相对表达量较对照组低(P <0.05);27nt-miR NC组、PDGF-BB诱导组OPN蛋白相对表达量较27nt-miR组高(P <0.05);27nt-miR组α-SMA、SM22α蛋白相对表达量较27nt-miR NC组高(P <0.05),OPN蛋白相对表达量较27nt-miR NC组低(P <0.05);27nt-miR组p70S6k、p-p70S6k与p-mTOR蛋白相对表达量较27nt-miR NC组低(P <0.05);各组经雷帕霉素处理后,27ntmiR-sponge组与27nt-miR NC组各蛋白相对表达量比较,差异均有统计学意义(P <0.05)。27nt-miR组p70S6k、p-p70S6k、mTOR、p-mTOR蛋白相对表达量较27nt-miR NC组低(P <0.05),27nt-miR-sponge组与27nt-miR NC组p-p70S6k、mTOR、p-mTOR蛋白相对表达量比较,差异均有统计学意义(P <0.05)。各组经MHY-1485处理后,27nt-miR组p70S6k、p-p70S6k、mTOR、p-mTOR蛋白相对表达量较27ntmiR NC组低(P <0.05);27nt-miR-sponge组与27nt-miR NC组各蛋白相对表达量比较,差异均有统计学意义(P <0.05)。结论 27nt-miR可能通过靶向m TOR/p70S6k信号通路从而调节大鼠血管平滑肌细胞增殖活力、增殖、迁移与表型转换。

运动通过微小RNA-181b/磷酸酶和张力蛋白同源物调控平滑肌表型缓解糖尿病大鼠血管损伤的研究

目的:观察有氧运动对2型糖尿病大鼠血管损伤的作用,探讨潜在的分子调控机制。方法:高糖高脂喂养联合链脲佐菌素注射建立大鼠2型糖尿病模型。选模型鼠20只随机分为糖尿病对照组(DC)和糖尿病运动组(DE),同龄正常饮食大鼠为正常对照组(NC),每组10只。DE组进行8周中等强度的跑台运动,其它组不运动。无创血压仪测试大鼠的心率、血压,HE染色观察血管壁病理学变化,电镜观察血管平滑肌细胞(vascular smooth muscle cells,VSMCs)的超微结构,实时荧光定量PCR(quantitative real-time PCR,qRT-PCR)检测血管微小RNA-181b(microRNA-181b,miR-181b)的表达,Western Blot检测血管α平滑肌肌动蛋白(α-smooth muscle actin,α-SMA)、波形蛋白(Vimentin)、磷酸肌醇3激酶(phospho inositide-3 kinase,PI3K)、磷酸酶和张力蛋白同源物(phosphatase and tensin homologue,PTEN)、蛋白激酶B(protein kinase B,AKT)等蛋白表达。结果:相比NC组,DC组大鼠心率(heart rate,HR)、收缩压(systolic blood pressure,SBP)、舒张压(diastolic blood pressure,DBP)、平均血压(mean blood pressure,MBP)显著降低(P<0.001);VSMCs失去典型的长梭形特征,表现为菱形,核膨大而不规则,细胞膜边界不清晰,密体、密斑少见;腹主动脉中膜显著增厚(P<0.05);收缩型特异蛋白α-SMA表达降低而合成型特异蛋白Vimentin表达升高(P<0.01);血管miR-181b的表达升高(P<0.001),其靶蛋白PTEN的表达降低(P<0.01),PI3K、AKT表达升高(P<0.01)。相比DC组,8周有氧运动使DE组的SBP、DBP、MBP显著升高(P<0.05或P<0.001);VSMCs呈长方形,核呈长椭圆形,细胞膜清晰完整,可见少许密体和密斑;收缩型特异蛋白α-SMA表达升高而合成型特异蛋白Vimentin表达降低(P<0.05);血管miR-181b的表达显著降低(P<0.001),PTEN蛋白表达升高而AKT表达下降(P<0.01或P<0.05)。结论:有氧运动具有缓解2型糖尿病大鼠血管损伤的作用,且可能机制为运动激活miR-181b/PTEN通路抑制下游AKT信号从而逆转糖尿病大鼠动脉VSMCs向合成表型转化。

Glycosylation-independent binding to extracellular domains 11-13 of mannose-6-phosphate/insulin-like growth factor-2 receptor mediates the effects of soluble CREG on the phenotypic proliferation of vascular smooth muscle cells

Background The present study aimed to investigate the detailed mode and specific sites for their binding as well as the functional relevance of this binding in the phenotypic proliferation of vascular smooth muscle cells(SMCs). Methods CREG knocked-down SMCs were employed to evaluate the biological activity of wtCREG and mCREG.Expressions of SMC differentiation markers SM myosin heavy chain(SM-MHC),SM-actin,heavy caldesmon and myocardin were determined by Western blotting using specific antibodies. Cellular growth of SMCs was assessed by bromide dewuridine (BrdU) incorporation and cell cycle analysis on fluorescence-activated cell sorting(FACS).A solid-phase binding assay was used to study the binding of CREG to extracellular domains of M6P/IGF2R.The cellular co-localization of the two recombinant CREGs with M6P/IGF2R was detected on SMC surface by immunoprecipitation and immunofluorescence analysis.Results The molecular weight of wtCREG was around 30 kD while that of the mCREG was～25 kD.Treatment of wtCREG with PNGase F reduced its molecular weight from～30 kD to～25 kD,whereas PNGase F treatment had no effect on the molecular weight of mCREG.Both wtCREG and mCREG proteins enhanced SMC differentiation,inhibited BrdU incorporation,and arrested cell cycle progression when added to the culture medium.In CREG knocked-down SMCs,the amount of CREG detected by immunoblotting in M6P/IGF2R immunoprecipitates was significantly reduced when compared to normal cells.Both recombinant CREGs co-immunoprecipitated with M6P/IGF2R, although slightly reduced amount of the mutant CREG was detected in M6P/IGF2R immunoprecipitates.Immunostaining revealed that His-tagged CREGs co-localized with IGF2R on the cell surface in a glycosylation-independent manner.In vitro binding assay showed that CREGs bound to M6P/ IGF2R extracellular domains 7-10 and 11-13 in a glycosylation -dependent and -independent manner,respectively.Further blocking experiments using soluble M6P/IGF2R fragments and M6P/IGF2R neutralizing antibody indicated that the biological activities of recombinant CREGs in SMC growth and the up-regulation of SMC differentiation markers were all abolished by treatment with the M6P/IGF2R neutralizing antibody. However,although the growth inhibitory effect of wtCREG was nearly abolished by D7-10 or D11-13,the effect of mCREG was only reversed by Dll-13,indicating that the binding to domains 11-13 is required for CREG to modulate the proliferation of SMCs.Conclusions These data suggest that solubleCREG proteins can exert their biological function via binding to the extracellular domains 7-10 and 11-13 of cell surface M6P/IGF2R in both a glycosylation-dependent and -independent manner.

HIAF-BRing快循环全储能脉冲电源高低压切换控制及其切换点平滑算法

应用于强流重离子加速器装置增强环(HIAF-BRing)的快循环全储能脉冲电源需要在极宽的输出电压范围内保持极高的控制精度,为此电源采用了高压功率单元和低压功率单元串联的拓扑方式,在低压段采用低压功率单元,电压升高之后切换到高压功率单元,通过高低压切换控制来实现电流全阶段的高精度输出。但是在样机实测中发现存在切换点的振荡问题,导致切换点处的输出电流绝对误差无法满足指标要求。本文提出了一种切换点平滑控制算法来平滑处理切换点占空比,给出了仿真结果,并且在HIAF-BRing快循环全储能脉冲电源样机上面实际验证了高低压切换控制方法及其切换点平滑控制算法的有效性。实验结果表明:100 A注入平台的输出电流绝对误差由±500 mA降至±50 mA,100 A注入平台的切换点处输出电流绝对误差由±1.16 A降至±120 mA,100 A注入平台输出精度较低的问题得以解决。

Output Feedback Controller Design for Discrete-time Switched Singular Systems

This paper is concerned with the problems of robust admissibility and static output feedback( SOF)stabilization for a class of discrete-time switched singular systems with norm-bounded parametric uncertainties.The objective is to design a suitable robust SOF controller guaranteeing the regularity,causality and asymptotic stability of the resulting closed-loop system under arbitrary switching laws. Based on the basic matrix inequality sufficient condition for checking the admissibility of switched singular systems,together with some matrix inequality convexifying techniques,the SOF controller synthesis is developed for the underlying systems. It is shown that the controller gains can be obtained by solving a set of strict linear matrix inequalities( LMIs). A simulation example is given to show the effectiveness of the proposed method.

Room Temperature Phosphorescence pH Switch Based on Photo-induced Electron Transfer

In this paper, photoinduced electron transfer(PET) phosphoroionophore, N-(1-bromo- 2-naphthylmethyl)-diethanolamine (BND) was synthesized and its phosphorescent characteristics were studied. The experimental results showed that strong phosphorescence could be observed in b-cyclodextrin aqueous solution only at low pH value. This system combined AND and NOT function to produce a three-input inhibit (INH) logic gate.

Smooth tracking control for conversion mode of a tilt-rotor aircraft with switching modeling

This paper investigates the state-tracking control problem in conversion mode of a tilt-rotor aircraft with a switching modeling method and a smooth interpolation technique.Based on the nonlinear model of the conversion mode,a switched linear model is developed by using the Jacobian linearization method and designing the switching signal based on the mast angle.Furthermore,an ℋ_(∞) state-tracking control scheme is designed to deal with the conversion mode control issue.Moreover,instead of limiting the amplitude of control inputs,a smooth interpolation method is developed to create bumpless performance.Finally,the XV-15 tilt-rotor aircraft is chosen as a prototype to illustrate the effectiveness of this developed control method.

微电网运行模式平滑切换控制策略研究

基于主从式控制模式的微网在发生非计划孤岛时,传统的PQ-V/F控制策略会导致微网难以维持系统的稳定运行。在分析微网运行模式切换时系统内电气量产生冲击原因的基础上,提出一种改进的储能变流器控制策略,通过在电压环中新增一个电压保持环路,配合外加电流环调节器,保证孤岛检测期间系统内的功率平衡,较好地解决了微网运行模式切换时系统内电压电流的冲击问题,实现运行模式的平稳过渡。在MATLAB/Simulink中搭建仿真模型,对比分析了采用传统控制策略和改进控制策略的控制效果,验证了改进控制策略的可行性和有效性。

三端口柔性多状态开关多模式平滑切换控制策略

光伏整县推进和电动汽车快速发展造成配电网末端电压偏高等电能质量问题,基于区域柔性互联的柔性多状态开关(flexible multi-state switch,FMSS)技术成为解决方案之一。针对柔性多状态开关PQ模式与VF模式间切换的波动及冲击性问题,提出在状态跟随控制器之后添加惯性环节,并改进相位预同步环节,可实现FMSS并离网工作模式的平滑切换。针对FMSS直流母线控制端的馈线故障导致系统运行崩溃问题,提出一种引入权值调节的控制策略,可实现系统稳定运行情况下,有功控制和直流母线电压控制的平滑切换。在MATLAB/Simulink环境下搭建了三端口FMSS仿真模型,对提出的控制策略进行了仿真验证,仿真结果实现了任意馈线故障下三端口FMSS无缝转供电功能。最后搭建物理实验平台,进一步验证了所提平滑切换策略的有效性。

一种CC/CV平滑切换的宽输出电压充电电路

目前多种动力蓄电池凭借着能量密度高、续航里程长和可循环使用等优势,在新能源汽车领域得到了广泛应用。针对当前以谐振电路为基础构建复合变换器应用于蓄电池充电存在输出电压范围、模式间切换、效率等不同问题,提出了一种四开关Buck-Boost与电容钳位LLC级联复用式变换器作为充电电路。该电路增益曲线的容性区和感性区均可工作,宽调频范围的容性区具有恒流特性,感性区的最佳谐振点具有恒压特性,利于实现蓄电池恒流恒压充电控制。频率与占空比的解耦控制拓宽了变换器的输出电压范围,且负载阻抗连续变化下电压增益连续,利于实现蓄电池恒流恒压平滑切换及满足不同电池充电控制方案,宽增益下的宽调控范围可减少输出纹波。拥有桥臂间移相软开关、复用桥臂增强软开关能力和降低通态电流、变压器低磁链及最终移动于最佳谐振点工作等电路特性,利于实现电能高效传输。仿真与实验结果验证了充电电路全程满足ZVS、ZCS的恒流恒压控制及充电模式间平滑切换特性。

基于RBFNN稳态逆模型的多端柔性多状态开关平滑切换策略

直流母线电压的稳定是柔性多状态开关正常运行的关键。柔性多状态开关(FMS)多工作模式的硬切换会导致直流母线电压产生剧烈波动,而采用平滑切换是实现母线电压稳定的最有效途径。文章详细分析了稳态逆模型平滑切换的原理,然后,针对其不足,深入研究了径相基函数神经网络(RBFNN)稳态逆模型平滑切换技术,给出了运用RBFNN改进稳态逆模型平滑切换的原理,进行了详细的实验验证。理论分析和实验结果显示,通过RBFNN控制修正PI输出来补偿扰动对系统的影响,将修正后的PI输出与稳态逆模型输出叠加生成内环参考值,有效平缓切换瞬间母线电压的振荡,能够实现直流母线电压波动小、响应速度快、动态特性佳、适应工况广等优点。

高血压和增龄对大鼠小动脉平滑肌表型转换和miR-143/145表达的影响

目的观察血管平滑肌细胞(VSMCs)表型在增龄与高血压过程中的变化特点,以及增龄与高血压对miR-143/145表达的影响,从而探讨VSMCs表型转换和miR-143/145在增龄与高血压血管中的关系。方法研究对象为1、3、9、16月龄正常大鼠(WKY组)及原发性高血压大鼠(SHR组),分别对其血压、肠系膜动脉形态、VSMCs表型标志蛋白、miR-143/145的表达进行定量。结果血压和血管形态均随年龄和高血压发展有显著变化,VSMCs收缩表型标志蛋白α-actin和Calponin的表达在3月达到峰值后随年龄逐渐下降,合成表型标志蛋白OPN在SHR中随年龄上升,α-actin、Calponin和OPN在同龄的各年龄段WKY组和SHR组之间差异均具有显著性(P<0.05)。miR-143/145在发育过程中表达升高而随衰老减少,且在3月时WKY组表达显著高于SHR组(P<0.05)。结论高血压和增龄促进VSMCs由收缩表型向合成表型转换,miR-143/145的表达在高血压和增龄发展过程中被抑制,miR-143/145可能参与了高血压和增龄发生发展过程中VSMCs的表型转换过程。

ET-1促进人血管平滑肌细胞的表型变化和增殖

目的：研究ET-1与VSMC表型变化和增殖的关系。方法：用MTT法研究ET-1对平滑肌细胞增殖的影响，3~H-TdR法测定ET-1对平滑肌细胞DNA合成的作用，流式细胞仪法观察对平滑肌细胞增殖周期的影响，逆转录聚合酶链法观察对平滑肌细胞表型变化的影响。结果：与对照组比较，ET-1明显促进平滑肌细胞增殖；促进平滑肌细胞DNA合成；促进平滑肌细胞从G_0期向S期的转变，G_0/G_1期细胞百分比明显降低，而S期细胞百分比增加；促进平滑肌细胞的表型转化，从第2d到第7d随时间延长1-Caldesmon表达逐渐增高。结论：ET-1促进平滑肌细胞表型转化，同时对平滑肌细胞增殖亦有明显的促进作用。

降钙素基因相关肽抑制动脉损伤后NF-κB表达及其对新生内膜增殖的作用

目的通过降钙素基因相关肽(calcitonin gene related peptide,CGRP)处理血管平滑肌细胞(vascular smooth muscle cells,VSMCs)和颈动脉损伤大鼠模型,探讨NF-κB在CGRP调节VSMCs表型改变和动脉损伤后新生内膜增殖中的作用。方法建立颈动脉损伤大鼠模型,并分为对照组和CGRP组(n=24),通过HE染色观察新生内膜形成情况,并Western blot检测两组动物损伤动脉中NF-κB p65蛋白表达情况。以组织块贴壁培养法获得VSMCs,并分为对照组、IL-1β组(给予IL-1β处理)、CGRP组(给予IL-1β+CGRP处理)和CGRP8-37组(在IL-1β+CGRP基础上,加CGRP8-37)(n=24),Western blot法检测细胞内NF-κB p65蛋白和细胞表型标志蛋白表达变化,MTT法检测细胞增殖能力。结果①对照组大鼠的颈动脉损伤后7 d时新生内膜明显增加,至28 d时基本稳定,而CGRP组7 d和28 d时新生内膜面积较对照组同时间点显著降低[7d:(2.09±0.26)vs(3.76±0.33);14 d:(3.52±0.41)vs(6.38±0.61),P<0.05];且与对照组比较,CGRP组1周时NF-κB p65蛋白表达水平明显降低(P<0.05),而28 d时两组NF-κB p65表达水平无差异(P>0.05)。②在体外培养VSMCs中,IL-1β处理显著激活细胞NF-κB p65蛋白表达(P<0.05),伴随着VSMCs收缩表现标志蛋白SMα-actin表达减少和OPN表达增加(P<0.05);同时再给予CGRP处理后,则显著减弱IL-1β诱导的NF-κB p65蛋白表达(P<0.05),且使VSMCs合成表现标志蛋白OPN表达减少。RT-PCR分析获得相一致的结果。同时,CGRP显著抑制IL-1β引起的VSMCs增殖。③CGRP受体阻断剂CGRP8-37可以阻断CGRP减弱IL-1β诱导的NF-κB p65蛋白表达作用,并抑制CGRP对VSMC表达蛋白调节作用。结论 CGRP与受体结合后抑制NF-κB激活,促进VSMCs分化标志基因表达,从而抑制细胞增殖,降低动脉损伤后新生内膜增殖,这对于防治动脉粥样硬化和血管成形术后再狭窄可能具有重要应用价值。

miRNA-21通过TPM1参与高糖诱导的人主动脉平滑肌细胞表型转化与增殖

目的探讨miRNA-21在高糖诱导的人主动脉平滑肌细胞表型转化与增殖中的作用,以及对靶基因原肌球蛋白1(tropomyosin 1,TPM1)表达的影响。方法体外培养人主动脉平滑肌原代细胞,利用脂质体转染miRNA-21mimic和inhibitor至细胞中,BrdU法检测高糖刺激miRNA-21过表达和缺失情况下人主动脉平滑肌细胞的增殖情况,荧光定量PCR检测转染前后高糖刺激时细胞miRNA-21和TPM1的表达情况,Western blot检测人主动脉平滑肌细胞中TPM1、骨桥蛋白(osteopontin,OPN)、平滑肌蛋白22α(smooth muscle 22alpha,SM22α)的表达情况。结果 10、20、25mmol/L D-葡萄糖刺激时人主动脉平滑肌细胞较正常对照组(0.613±0.022)显著增殖(0.725±0.026、0.913±0.024、1.513±0.082),差异有统计学意义(P<0.01);10、20、25mmol/L D-葡萄糖刺激时miRNA-21表达较对照组升高1.1、2.0、3.1倍(P<0.01);正常组细胞转染miRNA-21mimic后细胞增殖能力增强1.6倍,转染miRNA-21inhibitor后高糖组细胞增殖能力减弱(P<0.01);转染miRNA-21mimic后TPM1表达减弱,SM22α表达下调,OPN表达增加(P<0.01),转染miRNA-21inhibitor后TPM1表达上调,SM22α表达上调,OPN表达减少(P<0.01)。结论 miRNA-21可下调细胞TPM1的表达,从而促进人主动脉平滑肌细胞表型转化与增殖。