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51.
It has been known that Rho-associated protein kinase (ROCK) signaling regulates the migration of vascular smooth muscle cells (VSMCs). However, the isoform-specific roles of ROCK and its underlying mechanism in VSMC migration are not well understood. The current study thus aimed to investigate the roles of ROCK1/2 and their relationship to the MAPK signaling pathway in platelet-derived growth factor (PDGF)-induced rat aorta VSMC migration by manipulating ROCK gene expression. The results revealed that ROCK1 small interfering ribonucleic acid (siRNA) rather than ROCK2 siRNA decreased PDGF-BB-generated VSMC migration, and upregulation of ROCK1 expression via transfection of constructed pEGFP-C1/ROCK1 plasmid further increased the migration of PDGF-BB-treated VSMCs. In PDGF-treated VSMCs, ROCK1 siRNA did not affect the phosphorylation levels of ERK and p38 in the cytoplasm, but decreased the level of ERK phosphorylation in the nucleus. These findings demonstrate that activated ROCK1 can promote VSMC migration through facilitating phosphorylation and nuclear translocation of ERK protein. 相似文献
52.
大豆油中转基因成分的Nested PCR和Semi-nested PCR检测方法研究 总被引:3,自引:0,他引:3
对大豆油中DNA提取方法进行了研究,结果表明CTAB、SDS和Wizard试剂盒提取大豆油DNA均具有良好的效果。利用nested PCR和semi—nested PCR检测大豆(Roundup Ready)油中的转基因成分发现,该方法能够检测到大豆原油中的Lectin基因(112bp)、CaMV35S基因(147bP)和CP4-EPSPS基因(205bp),检测灵敏度达到10^-6ng/μl;但该方法未能从人豆成品油(一级)中扩增到上述基因,当中的转基因成分DNA含量低于10^-12ng/μl。 相似文献
53.
Liu Zhensheng Wang Xiaoming Li Zhigang Cui Duoying Li Xinqing 《Frontiers of Biology in China》2007,2(1):100-107
The feeding habitat selection of blue sheep (Pseudois nayaur) was studied by direct observation method in the Helan Mountains, China during winter (from November to December) and spring
(from April to June) from 2003 to 2004. We established 25 line transects to collect information on feeding habitats used by
blue sheep. Blue sheep in the study area preferred mountain savanna forests, a habitat dominated by Ulmus glaucescens, with medium tree density (<4 individuals / 400 m2), moderate tree height (4–6 m), higher shrub density (> 5 individuals / 100 m2), higher shrub (> 1.3 m), higher food abundance (> 50 g), moderate distance to human disturbance (< 500 m), and mild distance
to bare rock (< 2 m). Such habitats characterized by 12 ecological factors were preferred as feeding areas by blue sheep during
winter. Similar to habitat selection by the species during winter, blue sheep also showed a preference for mountain savanna
with tree dominated by Ulmus glaucescens and medium tree density (< 4 individuals / 400 m2) during spring. Nevertheless, blue sheep preferred medium tree height (< 6 m), moderate tree density (5–10 individuals /
100 m2), medium shrub height (1.3–1.7 m), higher food abundance (> 100 g), moderate altitude (< 2 000 m), moderate distance to water
resource (< 500 m), and medium hiding cover (50%–75%) during spring. Selection of the feeding habitats by sheep showed a significant
difference in vegetation type, landform feature, dominant tree, tree height, shrub density, distance to the nearest shrub,
food abundance, slope direction, slope degree, distance to water resource, and hiding cover between winter and spring. Results
of principal components analysis indicated that the first principal component accounted for 24.493% of the total variance
among feeding habitat variance during winter, with higher loadings for vegetation type, dominant tree, tree height, distance
to the nearest tree, shrub density, shrub height, altitude, distance to water resource, and distance to human disturbance.
In spring, the first principal components explained 28.777% of the variance, with higher loadings for vegetation type, distance
to the nearest tree, shrub height, distance to the nearest shrub, food abundance, altitude, and distance to human disturbance.
Translated from Zoological Research, 2005, 26(6): 580–589 [译自: 动物学研究] 相似文献
54.
Xin‐Hua Ma Zhi‐Biao Wang Lei Zhang Wei Li Cui‐Min Deng Tian‐Hua Zhong Guang‐Yu Li Wei‐Ming Zheng Yong‐Hong Zhang 《化学与生物多样性》2017,14(5)
One new ent‐kaurane diterpenoid, 11β,16α‐dihydroxy‐ent‐kauran‐19‐oic acid ( 1 ), together with eight known analogues 2 – 9 were isolated from the aerial parts of Wedelia prostrata. One of the acidic diterpenoids, kaurenoic acid ( 3 ), was converted to seven derivatives, 10 – 16 . All compounds were evaluated for their cytotoxic activity in vitro against human leukemia (K562), liver (HepG‐2), and stomach (SGC‐7901) cancer cell lines. Only four kaurenoic acid derivatives, 13 – 16 , with 15‐keto and substitutions at C(19) position, exhibited notable cytotoxic activities on these tumor cell lines with IC50 value ranging from 0.05 to 3.71 μm . Compounds 10 – 12 , with oxime on C(15) showed moderate inhibitory effects and compounds 1 – 9 showed no cytotoxicities on them. Structure–activity relationships were also discussed based on the experimental data obtained. The known derivative, 15‐oxokaurenoic acid 4‐piperdin‐1‐ylbutyl ester ( 17 ), induced typical apoptotic cell death in colon SW480 cells upon evaluation of the apoptosis‐inducing activity by flow‐cytometric analysis. 相似文献
55.
2008年至2009年间,在湖南和湖北两省的活禽市场中分离到了14株H6亚型禽流感病毒,为了解这14株病毒之间的分子特征和差异,我们运用PCR和测序鉴定对这14株病毒的NA基因进行了分型,并对其表面基因HA和NA进行序列测定及序列分析.14株H6亚型病毒中,H6N2亚型12株,H6N6亚型2株.序列测定和进化分析结果显示:DK/HN/284的HA基因与其它13株的HA差异性较大,差异性达到19.4%~20.2%,其余13株毒同源性在94.2%~99.9%;N2亚型NA基因的同源性在91.1%~99.9%,差异性比较大;两株N6亚型NA基因同源性为89.5%,差异明显.这些数据表明:不同毒株呈现一定的地域性差异.与我国周边其它地区的H6亚型禽流感毒株序列进行比较发现,只有DK/HN/284的HA基因与香港早期的毒株可能有着共同的来源,其余都与香港和韩国等的毒株有着较大的差异性,并且各个毒株的HA基因上潜在的糖基化位点和受体结合位点也有所不同,这些数据表明,这些毒株表现出明显的异源性. 相似文献
56.
YM Cui XW Dong W Chen WJ Wang YG Li HL Zhu 《Journal of enzyme inhibition and medicinal chemistry》2012,27(4):528-532
Two mononuclear copper(II) complexes, [Cu(C(15)H(16)NO(2))(2)] (1) and [Cu(C(6)H(9)N(2)O(4))(2)·3H(2)O] (2·3H(2)O), were synthesised and structurally characterised by single-crystal X-ray analysis. The copper(II) atom adopts a square-planar environment in complex 1, while the geometry in 2·3H(2)O could be described as the distorted square pyramidal. Complexes 1 and 2·3H(2)O were evaluated for their inhibitory activities against Helicobacter pylori (H. pylori) urease in vitro. They both were found to have strong inhibitory activities against H. pylori urease comparable to that of acetohydroxamic acid (AHA). A docking simulation was performed to position 2 into the H. pylori urease active site to determine the probable binding conformation. 相似文献
57.
不饱和脂肪酸在低渗牵张加强豚鼠胃窦平滑肌细胞毒蕈碱电流中的作用 总被引:1,自引:0,他引:1
利用全细胞膜片钳技术在急性分离的胃窦平滑肌细胞上记录离子电流的方法 ,探讨外源性不饱和脂肪酸是否参与低渗牵张加强毒蕈碱电流的过程。在豚鼠胃窦平滑肌细胞上膜电位被钳制在 - 2 0 0mV等渗状态时 ,5 0 μmol/L卡巴胆碱 (carbachol,CCh)引起的毒蕈碱电流 (ICCh)作为对照 ,发现低渗牵张可以使ICCh明显增加到对照的 2 2 6 0±2 1 0 %。当用含 5 μmol花生四烯酸 (arachidacid ,AA)、亚麻酸 (linoleicacid ,LA)或亚油酸 (oleicacid,OA)细胞外液灌流时 ,ICCh分别被抑制在对照的 3 8± 0 6%、3 5 2± 0 8%和 66 6± 0 6%。在这种情况下 ,低渗牵张刺激可以使ICCh分别增加到 10 6 0± 2 5 %、173 2± 6 8%和 2 2 2 1± 11 0 %。 5 μmol/LAA抑制低渗牵张增加的毒蕈碱电流 5 1 2± 3 8% ,而在等渗状态下抑制ICCh为 96 2± 1 6%。上述结果提示 ,不饱和脂肪酸中双键数目越多 ,抑制效应越强 ;但不饱和脂肪酸不参与低渗刺激加强毒蕈碱电流的过程。 相似文献
58.
59.
Wang J Zhang Z Hu Y Hou X Cui Q Zang Y Wang C 《Physiological research / Academia Scientiarum Bohemoslovaca》2007,56(1):17-23
Given the potential clinical benefit of inhibiting Na+/Ca2+ exchanger (NCX) activity during myocardial ischemia reperfusion (I/R), pharmacological approaches have been pursued to both inhibit and clarify the importance of this exchanger. SEA0400 was reported to have a potent NCX selectivity. Thus, we examined the effect of SEA0400 on NCX currents and I/R induced intracellular Ca2+ overload in mouse ventricular myocytes using patch clamp techniques and fluorescence measurements. Ischemia significantly inhibited inward and outward NCX current (from -0.04+/-0.01 nA to 0 nA at -100 mV; from 0.23+/-0.08 nA to 0.11+/-0.03 nA at +50 mV, n=7), Subsequent reperfusion not only restored the current rapidly but enhanced the current amplitude obviously, especially the outward currents (from 0.23+/-0.08 nA to 0.49+/-0.12 nA at +50 mV, n=7). [Ca2+]i, expressed as the ratio of Fura-2 fluorescence intensity, increased to 138+/-7% (P<0.01) during ischemia and to 210+/-11% (P<0.01) after reperfusion. The change of NCX current and the increase of [Ca2+]i during I/R can be blocked by SEA0400 in a dose-dependent manner with an EC50 value of 31 nM and 28 nM for the inward and outward NCX current, respectively. The results suggested that SEA0400 is a potent NCX inhibitor, which can protect mouse cardiac myocytes from Ca2+ overload during I/R injuries. 相似文献
60.
人肺腺癌细胞A—549和正常细胞HBE的蛋白质组差异分析 总被引:28,自引:0,他引:28
为了研究人肺腺癌细胞A 5 49和正常细胞HBE的蛋白质组差异 ,用固相pH梯度双向凝胶电泳分离人肺腺癌细胞系A 5 49和正常细胞HBE的总蛋白质 ,银染显色 ,PDQuest 2 DE软件分析 ,对部分差异蛋白质点进行基质辅助激光解吸电离飞行时间质谱 (MALDI TOF MS)测定其胶内酶解后的肽质指纹图谱 ,用PeptIdent软件查询SWISS PROT数据库。结果获得了分辨率和重复性均较好的双向电泳银染图谱 ,图象分析探测到A 5 492 DE图谱的平均蛋白质点数为 (890± 38)个 ,HBE的平均蛋白质点数为 (75 7± 2 7)个 ,不同胶间蛋白质点的位置偏差在IEF方向为 (2 .85± 0 .48)mm ,在SDS PAGE方向为 (2 .6 9± 0 .37)mm。差异表达分析发现A 5 49和HBE图谱有5 35个蛋白质点相互匹配 ,其中A 5 49有 35 5个未被匹配 ,HBE中有 2 2 2个未被匹配 ;对A 5 49和HBE中的 18个差异蛋白质点分别进行肽质指纹分析 ,经数据库查询 ,初步鉴定为一些与物质代谢、细胞因子、信号转导有关的蛋白质。提示人肺腺癌细胞A 5 49和正常细胞HBE的蛋白质组具有差异 ,这种蛋白质组的差异分析有助于进一步研究肺腺癌的相关蛋白质及分子标记物 相似文献