Involvement of calcium-sensing receptor in oxLDL-induced MMP-2 production in vascular smooth muscle cells via PI3K/Akt pathway

Matrix metalloproteinase-2 (MMP-2) is constitutively expressed in vascular smooth muscle cells (VSMCs) and up-regulated in atherosclerotic lesion by various stimuli, such as oxidized low-density lipoprotein (oxLDL). Calcium-sensing receptor (CaSR) is also expressed in VSMCs, but it remains unclear whether CaSR is associated with overproduction of MMP-2 in VSMCs. In this study, the expression of MMP-2 was detected by real-time PCR and Western blot analysis, and the gelatinolytic activity of MMP-2 was measured using gelatin zymography. Our results showed that oxLDL enhanced MMP-2 expression and activity in rat aortic VSMCs in a time- and dose-dependent manner. In addition, CaSR expression was up-regulated by oxLDL. Manipulating CaSR function in these cells by NPS2390 (an antagonist of CaSR) or GdCl(3) (an agonist of CaSR) affected the oxLDL-induced MMP-2 production. In VSMCs, oxLDL stimulated the rapid activation of phosphatidylinositol 3-kinase (PI3K)/Akt signal pathway, as determined by Western blot analysis. Phosphorylation of Akt and MMP-2 production stimulated by oxLDL were attenuated by LY294002 (a specific inhibitor of PI3K). Activation of Akt was suppressed by NPS2390 but enhanced by GdCl(3). In contrast, oxLDL had no stimulatory effect on the phosphorylation of JNK, and pretreatment with SP600125 (an inhibitor of JNK) produced no significant effect on oxLDL-induced MMP-2 production. These results suggest that CaSR mediates oxLDL-induced MMP-2 production in VSMCs via PI3K/Akt signal pathway.     

Diversity among Single Zoospore Isolates Derived from Single-zoosporangia of Phytophthora sojae Kauf. and Gerd

Phytophthora sojae Kauf. and Gerd, a host specific pathogen to soybean, causes pre and postemergence damping-off and root and stem rot on soybean. The pathogen evokes severe yield losses in most soybean growing areas worldwide. The objective of this study was to determine phenotypic and genotypic diversity among single zoospore isolates (SZIs) originating from two single zoosporangia (Ps411-1 and Ps411-2) derived from the same parental isolate of P . sojae Ps411. Results showed that colony morphology and growth rate of 32 SZIs derived from sporangium Ps411-1 and 35 SZIs released from sporangium Ps411-2 did not significantly differ from the parental isolate Ps411. Pathogenicity of the SZIs was tested on three resistant and three susceptible Chinese soybean cultivars. While the majority of SZIs derived from sporangium Ps411-1(59.4%) and sporangium Ps411-2(71.4%) retained the same virulence spectrum as the parental isolate, the other SZIs of both progenies demonstrated either a higher or a lower level of virulence compared to that of parental isolate. A low level genetic variability in the populations of both single zoospore progenies was also demonstrated using the sequence-related amplified polymorphism (SRAP) technique. Cluster analysis separated the SZIs from both zoosporangia, Ps411-1 and Ps411-2, into four and three SRAP groups, respectively. No close correlation among SRAP and virulence could be established among SZIs. The results of this study suggest that virulence variability may be regarded as part of the total genetic changes among the zoospore progenies derived from single-zoosporangia. The pathogenic variability during asexual reproduction may play a role in changing the virulence structure of P . sojae .     

飞机草花蕾中Beclin1基因的克隆与表达

本文以入侵植物飞机草的不同时期花蕾为材料,利用RT-PCR法扩增得到了与PCD相关的类Beclin1基因的部分cDNA序列(大约700bp),与烟草叶片中的基因序列（AY701316）同源性为95%;Northern blotting结果表明类Beclin1基因在花蕾发育中期的表达量高于初期和后期;通过DNA ladder检测表明在花蕾发育过程中伴随着PCD的发生,这些结果表明花蕾发育中期是PCD初期发生的活跃期,是绒毡层逐渐退化和花粉不断形成的过程。通过对生殖过程中的细胞程序性死亡的分子生物学研究,初步揭示了飞机草入侵过程与PCD的相互关系。     

飞机草花蕾中Beclin1基因的克隆与表达

以入侵植物飞机草的不同时期花蕾为材料,利用RT-PCR法扩增得到了与PCD相关的类Beclin1基因的部分cDNA序列(大约700 bp),与烟草叶片中的基因序列(AY701316)同源性为95%;Northern blotting结果表明类Beclin1基因在花蕾发育中期的表达量高于初期和后期;通过DNA ladder检测表明在花蕾发育过程中伴随着PCD的发生,这些结果表明花蕾发育中期是PCD初期发生的活跃期,是绒毡层逐渐退化和花粉不断形成的过程.通过对生殖过程中的细胞程序性死亡的分子生物学研究,初步揭示了飞机草入侵过程与PCD的相互关系.     

P16^INK4、Rb基因表达在肺癌发生中协调性研究

采用mRNA原位双杂交和免疫组织化学方法对31例非小细胞肺癌组织进行P16^INK、Rb基因、Rb基因表达水平及其相关性的研究。结果显示,以Dig-碱性磷酸酶－NBT／BCIP系统检测P16^INK4基因转录,阳性结果呈蓝色,阴性杂交率为22．6％（7／31）;以Bio－辣根过氧化物酶－AEC系统检测Rb基因转录,阳性结果为红色,阴性率为16．1％（5／31）。免疫组织化学检测显示P16^INK4蛋白质阴性率为42％（13／31）;Rb蛋白表达阴性率为19．4％（6／31）。Rb、P16^INK4基因在非小细胞肺癌发生中起协同调控作用,以P16^INK4基因表达异常为主。     

甘肃省大熊猫数量及栖息地现状

20 0 0～ 2 0 0 3年的调查表明 ,甘肃省野生大熊猫 (Ailuropodmelanoleuca)现有 1 1 7只 ,分布在文县 1 0 3只、迭部县 1 1只、舟曲县 1只和武都县 2只。栖息地呈互不相连的 5块 ,总面积 1 82 7 .3 5km2 ,其中白水江保护区 1 1 65 .1 6km2 、迭部县 5 1 8. 91km2 ,为 2块面积较大的稳定栖息地 ,其余 3块为面积很小、不稳定的栖息地。     

Involvement of calcium-sensing receptor in cardiac hypertrophy-induced by angiotensinII through calcineurin pathway in cultured neonatal rat cardiomyocytes

Cardiac hypertrophy is a common pathological change accompanying cardiovascular disease. Recently, some evidence indicated that calcium-sensing receptor (CaSR) expressed in the cardiovascular tissue. However, the functional involvement of CaSR in cardiac hypertrophy remains unclear. Previous studies have shown that CaSR caused accumulation of inositol phosphate to increase the release of intracellular calcium. Moreover, Ca²⁺-dependent phosphatase calcineurin (CaN) played a vital role in the development of cardiac hypertrophy. Therefore, we investigated the expression of CaSR in cardiac hypertrophy-induced by angiotensin II (AngII) and the effects of CaSR activated by GdCl₃ on the related signaling transduction pathways. The results showed that AngII induced cardiac hypertrophy and up-regulated the expression of CaSR, meanwhile increased the intracellular calcium concentration ([Ca²⁺]_i) and activated CaN hypertrophic signaling pathway. Compared with AngII alone, the above changes were further obvious when adding GdCl₃. But the effects of GdCl₃ on the cardiac hypertrophy were attenuated by CsA, a specific inhibitor of CaN. In conclusion, these results suggest that CaSR is involved in cardiac hypertrophy-induced by AngII through CaN pathway in cultured neonatal rat cardiomyocytes.     

Building skeletally diverse architectures on the Indoline Scaffold: the discovery of a chemical probe of focal adhesion kinase signaling networks

Inspired by bioactive indoline alkaloid natural products, here, we report a divergent synthesis approach that led to skeletally diverse indoline alkaloid-inspired compounds. The natural product-inspired compounds obtained were then subjected to a series of in vitro and cellular assays to examine their properties as modulators of focal adhesion kinase (FAK) activity. This study resulted in the identification of a promising lead inhibitor of FAK (42), which also showed activity in a wound healing and cell invasion assay. The in silico study of the lead compound (42) was also undertaken.     

耐力训练抑制急性低氧时骨骼肌线粒体生物能学变化:ROS和UCP3的作用(英文)

骨骼肌线粒体解耦联蛋白3（uncoupling protein3,UCP3）在低氧时的生理作用尚不清楚。本研究观察了大鼠在耐力训练前后,模拟急性高原低氧各时间点的骨骼肌线粒体UCP3 mRNA和蛋白表达、线粒体呼吸功能、活性氧（reactive oxygen species,ROS）产生速率以及锰超氧化物歧化酶（manganese superoxide dismutase,MnSOD）表达和活性的变化。急性低氧导致线粒体一系列生物能学功能障碍。未训练大鼠UCP3蛋白在4h时比静息时升高了60％,而MnSOD蛋白含量及活性在低氧暴露过程中无显著变化;UCP3蛋白上调通过降低电子传递链耦联程度抑制O2-产生,但同时降低了ATP合成效率。耐力训练显著抑制急性低氧诱导的骨骼肌UCP3蛋白上调（67％;S42％）。训练组大鼠的ROS产生速率在低氧2h、4h和6h时显著低于未训练组;MnSOD蛋白含量及活性分别较术训练组提高了50％和34％。训练组人鼠MnSOD上调可增加线粒体对ROS的耐受力,进而抑制UCP3蛋白表达,从而提高氧化磷酸化效率。急性低氧中,未训练组大鼠呼吸控制比（respiratory control ratio,RCR）和磷氧比（ADP to oxygen consumption ratio,P／O）显著降低,而训练组RCR和P／O保持相对稳定。以上结果提示：（1）模拟急性高原低氧可诱导UCP3 mRNA及蛋白表达升高,从而降低升高了的线粒体膜电位（△ψ）,使ROS的产生减少;（2）耐力训练可抑制低氧诱导的UCP3表达上调,提高ROS酶学清除能力,从而提高线粒体氧化磷酸化效率。