MMP-2、MMP-9及其抑制剂在肺癌中的表达与临床意义

目的探讨肺癌组织中MMP2、MMP9及其抑制剂的表达与肺癌的生长、转移等临床特征及预后的关系.方法采用免疫组织化学法SP法检测45例肺癌组织中MMP2、MMP9及其抑制剂的表达,观察它们与肺癌的生长、TMN分期的关系.结果MMP2、MMP9、TIMP1和TIMP2在45例肺癌组织中的阳性表达率分别为57.78%(26/45)、37.78%(17/45)、35.56%(16/45)及51.11%(23/45);它们的表达与肺癌的原发灶范围、淋巴结转移、远处转移、TNM分期及平均生存时间有统计学意义(P<0.05).结论MMP2、MMP9及其抑制剂的表达与肺癌的TNM分期及平均生存时间关系密切,它们在组织中的高表达是判断肺癌预后的独立因素.     

肝再生过程中肾desmin和GFAP的表达以及MMPs的变化

采用免疫组织化学法和明胶酶谱电泳法研究大鼠肝部分切除(PH)后再生过程中肾结蛋白(desmin)和胶质纤维酸性蛋白(GFAP)的表达以及基质金属蛋白酶-2(MMP-2),-9(MMP-9)的活性变化.免疫组织化学结果显示,肝再生过程中肾小球系膜细胞、足细胞和间质细胞表达desmin和GFAP,而且二者的表达在PH后均经历了先减少后恢复的过程.明胶酶谱电泳结果显示,在对照组,检测到1条92 kD(pro MMP-9,MMP-9酶原形式)蛋白酶带,具有强的活性.在PH后8 d到14 d检测到了92 kD,86 kD(MMP-9),72 kD(pro MMP-2,MMP-2酶原形式)和66 kD(MMP-2)4条蛋白酶带.从第10 d到14 d,pro MMP-9和MMP-9活性逐渐增强,pro MMP-2和MMP-2活性逐渐降低.     

Effect of matrix metallo-proteinase-26 (MMP-26) during embryo implantation in the mouse

Matrix metalloproteinase-26 (MMP-26, endometase and matrilysin-2), a novel member of the MMPs family, is detected not only in the placenta and uterus, but is widely expressed in malignant tumors from different sources as well as in diverse tumor cell lines. However, the function of MMP-26 in the reproductive system has never been reported. Expression of MMP-26 in mouse embryos and the function of the MMP-26 antibody during mouse embryo implantation was examined for the first time by injecting the uterine horn, immunohistochemistry,in situ hybridization, co-culture of mouse blastocysts and uterine monolayer epithelial cells, Western blot, RT-PCR, Northern blot and zymography. Our results show that there is strong expression of MMP-26 mRNA and protein in the mouse embryo. Furthermore, the MMP-26 antibody dramatically inhibited mouse embryo implantation and significantly inhibited adhesion and outgrowth of mouse blastocysts onin vitro uterine monolayer epithelial cells. At the same time, the MMP-26 antibody inhibited the expression of integrin αV mRNA and protein in a dose-dependent manner. These data suggest that MMP-26 may play a role in some of the tissue-remodeling events associated with the invasion of the endometrium by trophoblast cells and facilitate successfully embryo implantation.     

Regulation of embryo implantation by nitric oxide in mouse

Intrauterine injection and zymography were used to investigate the effect of nitric oxide (NO) on embryo implantation in mice. On day 3, one uterine horn of female pregnant mice was injected intraluminally with various doses of nitric oxide synthase (NOS) inhibitor, N-nitro-L-arginine methyl ester (L-NAME), while the contralateral horn served as control. Animals were sacrificed by cervical dislocation on day 7 of gestation, and the number of implanted embryos in each horn was calculated. The results showed that lower doses (0.05 mg L-NAME) did not inhibit implantation significantly (P > 0.05), but high doses (0.2 mg L- NAME) resulted in a significant reduction in the number of implanted embryos (P < 0.05). Co-administration of SNP, a generator of NO, with L-NAME would reverse the antiimplantation effect of L-NAME. To further understand the precise mechanism of NO in implantation, matrix metalloproteinase (MMPs) activities were detected by gelatin zymography. The reduction in the number of implanted embryos in 0.2 mg L-NAME treated group was associated with decreased MMP-9 activity but a stable MMP-2 activity. The activities of MMP-2 and MMP-9 were not changed in L-NAME and SNP treated group. These data suggest that NO acts as a mediator to regulate the activity of MMP-9, and facilitates embryo implantation.     

Suppression of murine breast cancer metastasis by selective inhibition of CXCR4 by synthetic polypeptide derived from viral macrophage inflammatory protein II

Stromal cell-derived factor-1 and its receptor CXC chemokine receptor-4 (CXCR4) have been implicated in breast cancer metastasis. A significant association between HER2 and CXCR4 expression has been observed in human breast tumor tissues, and overexpression of CXCR4 is essential for HER2-mediated tumor metastasis. Moreover, CXCR4 expression is low in normal breast tissues and high in malignant tumors, suggesting that a blockade of CXCR4 may limit tumor metastasis. The present study investigated the action of a synthetic antagonist 21-mer peptide derived from viral macrophage inflammatory protein II against CXCR4 (NT21MP) in inhibiting metastasis in vitro and in vivo. The results showed that chemotaxis of SKBR3 cells toward SDF-1α was reduced by NT21MP in a dose-dependent manner (P < 0.05). NT21MP inhibited tumor growth at 500 μg/kg and in combination with Herceptin, the anti-HER2 antibody. The in vivo metastatic assay showed that NT21MP significantly inhibited pulmonary metastasis, and the number of metastatic tumor nodes on the surface of the lung was greatly decreased. Compared with the saline-treated control group, PCNA expression was dose-dependently decreased by NT21MP, the percentage of apoptotic cells was increased, and CXCR4 mRNA and protein expression were downregulated. In conclusion, NT21MP inhibits cellular prolifer-ation, promotes apoptosis by downregulating CXCR4 expression, and suppresses the progression of primary and metastatic tumors. CXCR4 may be a useful therapeutic target for breast cancer, and NT21MP may serve as a potential target drug for the treatment of breast cancer metastasis.     

基于矩阵式变换器的异步电动机矢量控制

为提高交流调速系统的运行性能并满足节能的要求,提出了一种适用于矩阵式变换器驱动异步电动机调速系统的组合控制策略,实现了矩阵式变换器的空间矢量调制和异步电动机的直接磁场定向矢量控制。将矩阵式变换器的优点和矢量控制的优点结合起来,实现了异步电动机的高性能控制。仿真结果表明:使用该控制策略的调速系统在加减速运行和负载转矩变化等场合均具有良好的动态性能;四象限运行结果证明了该系统可将能量回馈至电网,实现了节能的目的。稳态运行实验结果验证了上述控制方法的可行性和有效性。     

一种基于稀疏序列的量子CSS码的构造

量子CSS码是一种简单、有效的量子码构造方法,已被应用到各类特性的量子码的构造之中.针对低密度奇偶校验码(LDPC)的优异性能,利用稀疏序列构造LDPC码校验矩阵的方法,提出了一种构造量子低密度奇偶校验码校验矩阵构造方法,采用快速编码算法,获得相应的量子码.最后,以(3,8)(16,6)量子码为例给出量子低密度奇偶校验...     

微波辐射-ZnCl2活化柚子皮制备活性炭

以废料柚子皮为原料,ZnCl2为活化剂,采用微波辐射法制备了活性炭．采用正交实验研究了活化剂浓度、微波功率和活化时间对活性炭得率和吸附性能的影响．同时采用美国ASAP-2020吸附仪测定了所制备活性炭的Na吸附脱附等温线和孔径分布,采用红外光谱分析了样品的表面官能团,采用扫描电镜观察了样品的表面形貌．结果表明：ZnCl2质量浓度为50％,微波功率为850W,活化时间为8min工艺条件下制得的活性炭碘吸附值为1024mg／g;亚甲基蓝吸附值为160mL／g,产率为34．5％;比表面积为1490mm／g,总孔容为1．574cm^3／g,平均孔径为4．225nm．该活性炭为中孔型,比市售活性炭有更加发达的孔隙结构及更多的表面含氧基团,吸附性能优于市售活性炭．     

Al12Pb团簇几何构形对其稳定性的影响

基于第一性原理，在密度泛函理论框架下，用局域密度近似（LDA）和广义梯度近似（GGA）研究20面体Al12Ph团簇的几何构形和稳定性，计算了束缚能（BE）、电子亲合能、原子间平衡间距、最高占据轨道（HOMO）与最低未占据轨道（LUMO）间的能隙和最高占据轨道（HOMO）电子构型．此外，还计算了团簇的原子相互作用能．结果表明：具有C5对称性团簇Al12Ph的束缚能比具有Ih对称性团簇Al12Ph的束缚能更低，稳定性更好；计算数据与实验结果相符合。     

Al_(12)Pb团簇几何构形对其稳定性的影响

基于第一性原理,在密度泛函理论框架下,用局域密度近似(LDA)和广义梯度近似(GGA)研究20面体Al12Pb团簇的几何构形和稳定性,计算了束缚能(BE)、电子亲合能、原子间平衡间距、最高占据轨道(HOMO)与最低未占据轨道(LUMO)间的能隙和最高占据轨道(HOMO)电子构型.此外,还计算了团簇的原子相互作用能.结果表明:具有C5v对称性团簇Al12Pb的束缚能比具有Ih对称性团簇Al12Pb的束缚能更低,稳定性更好;计算数据与实验结果相符合.     

芴酮引发丙烯酸两步接枝LDPE膜表面改性的研究

采用两步接枝方法,研究了芴酮(FL)引发丙烯酸(AA)在低密度聚乙烯(LDPE)膜表面的接枝聚合过程,探讨了单体浓度、聚合温度等因素对表面接枝的影响。结果表明：在单体质量分数为5%~20%,聚合温度为70~90℃范围内,增大单体浓度、提高聚合温度,有利于接枝反应的进行。采用称量法、表面水接触角测定法、红外光谱分析等手段对表面接枝膜进行了表征,结果表明丙烯酸被成功地引入到LDPE膜表面,接枝率最高达到8.24%,改善了LDPE膜表面的亲水性。     

光场调制下的两个二能级原子的线性熵研究

本文应用J-C模型研究了两个二能级原子依次穿过一个高Q光场时系统的状态波函数和密度矩阵,并计算了两个二能级原子子系统的线性熵,分析了此时两个原子的纠缠特性。     

Effect of sintering on the relative density of Cr-coated diamond/Cu composites prepared by spark plasma sintering

Cr-coated diamond/Cu composites were prepared by spark plasma sintering. The effects of sintering pressure, sintering temperature, sintering duration, and Cu powder particle size on the relative density and thermal conductivity of the composites were investigated in this paper. The influence of these parameters on the properties and microstructures of the composites was also discussed. The results show that the relative density of Cr-coated diamond/Cu reaches ~100% when the composite is gradually compressed to 30 MPa during the heating process. The densification temperature increases from 880 to 915℃ when the diamond content is increased from 45vol% to 60vol%. The densification temperature does not increase further when the content reaches 65vol%. Cu powder particles in larger size are beneficial for increasing the relative density of the composite.     

数据驱动建立地层原油黏度计算新方法

针对海上勘探评价阶段稠油油田地层流体取样少或无取样的问题,通过对大量渤海地区已取样稠油流体数据统计,应用数据矩阵分析探寻影响地层原油黏度的主控因素及不同参数与地层原油黏度的关系,采用非线性回归建立地层原油黏度与其他参数之间关系的经验公式,同时建立不同参数条件的地层原油黏度与地面密度的取值图版。新经验公式计算的地层原油黏度与实测地层原油黏度平均误差5.6%,同时应用经验公式和原油黏度确定综合图版对某海上稠油流体性质进行分析,两种方法研究结果相当,说明新方法的可靠性。基于数据驱动建立的地层原油黏度公式和图版成果可解决海上稠油油田地层流体取样少或无取样的问题,为油田开发方案编制、开发方式选择、采收率预测、平台设施设计及原油输送提供重要参考依据。     

表面活性氧物种对A-H(A=C,O,N)键活化机理的研究进展

表面吸附态活性氧物种如O~*、OH~*等对H_2O、CH_3OH、CH_4、NH_3所含O-H、C-H以及N-H键的活化有着十分重要的作用,其调控行为与催化剂的本身电子结构、氧物种的碱性以及A-H中H原子的酸性等有着非常密切的关系.通过表面吸附氧物种的修饰可以有效地控制A-H键的活化程度,从而达到调控反应的目的.利用40篇文献综述了近些年来理论科学工作者在该方面的研究成果,期望为实验工作提供有价值的理论指导依据.     

Progressive Failure Analysis of Quasi-isotropic Self-reinforced Polyethylene Composites by Comparing Unsupervised and Supervised Classifications of Acoustic Emission Data

Unsupervised and supervised pattern recognition（ PR）techniques are used to classify the acoustic emission（ AE） data originating from the quasi-isotropic self-reinforced polyethylene composites,in order to identify the various mechanisms in the multiangle-ply thermoplastic composites. Ultra-high molecular weight polyethylene / low density polyethylene（ UHMWPE / LDPE）composites were made and tested under quasi-static tensile load. The failure process was monitored by the AE technique. The collected AE signals were classified by unsupervised and supervised PR techniques, respectively. AE signals were clustered with unsupervised PR scheme automatically and mathematically. While in the supervised PR scheme,the labeled AE data from simple lay-up UHMWPE / LDPE laminates were utilized as the reference data.Comparison was drawn according to the analytical results. Fracture surfaces of the UHMWPE / LDPE specimens were observed by a scanning electron microscope（ SEM） for some physical support. By combining both classification results with the observation results,correlations were established between the AE signal classes and their originating damage modes. The comparison between the two classifying schemes showed a good agreement in the main damage modes and their failure process. It indicates both PR techniques are powerful for the complicated thermoplastic composites. Supervised PR scheme can lead to a more precise classification in that a suitable reference data set is input.