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1.
目的:探讨脑出血对酵母沉默信息调节因子2(Sirt2)和炎症的影响。方法:将胶原酶Ⅳ注入SD大鼠右侧 纹状体中建立脑出血模型,通过免疫印迹和ELISA 等方法测定大鼠脑出血后48 h 的Sirt2 的表达及炎症变化。利 用Hemin 诱导PC12 细胞损伤模拟体外脑出血模型,并检测Sirt2 及炎症变化;采用短发夹RNA(shRNA)-Sirt2 沉 默Sirt2 在PC12 细胞中的表达及对炎症的影响。结果:手术后48 h 脑出血行为学评分最低。脑出血组Sirt2 的表达 显著高于假手术组。脑出血组IL-6、IL-1β 表达显著升高。结论:脑出血可以促进Sirt2 的表达和炎症反应,降低 Sirt2 的表达可减缓炎症反应。 关键词 脑出血;沉默信息调节  相似文献   
2.
目的:探讨单孔胸腔镜下肺癌手术术后胸腔引流时间的影响因素。方法:本研究采用回顾性分析方法,回顾我院2018年01月至2019年12月原发性肺癌患者经单孔胸腔镜手术治疗的病例199例。按照术后胸腔引流时间分为两组,Ⅰ组(术后胸腔引流时间<5天)和Ⅱ组(术后胸腔引流时间≥5天)。对于影响术后胸腔引流时间的可能因素在两组间先采用单因素分析的方法筛选,再将筛选出来的对术后胸腔引流时间可能有意义的影响因素进行二项Logistic多因素回归分析。结果:经单因素分析及二项Logistic多因素回归分析结果显示:年龄≥60岁、手术部位、肺段切除术、胸膜粘连、手术时间≥180 min、术后早期下床活动是术后胸腔引流时间的独立影响因素(P<0.05)。结论:对于具有多个延长术后胸腔引流时间的独立影响因素的患者,应制定个体化管理方案,尽可能减少术后胸腔引流时间,减少住院天数,加快患者康复。  相似文献   
3.
Deoxynivalenol (DON) has broad toxicity in animals and humans. In this study the impact of DON treatment on apoptotic pathways in PC12 cells was determined. The effects of DON were evaluated on (i) typical indicators of apoptosis, including cellular morphology, cell activity, lactate dehydrogenase (LDH) release, and apoptosis ratio in PC12 cells, and on (ii) the expression of key genes and proteins related to apoptosis, including Bcl-2, Bax, Bid, cytochrome C (Cyt C), apoptosis inducing factor (AIF), cleaved-Caspase9, and cleaved-Caspase3. DON treatment inhibited proliferation of PC12 cells, induced significant morphological changes and apoptosis, promoted the release of Cyt C and AIF from the mitochondria, and increased the activities of cleaved-Caspase9 and cleaved-Caspase3. Bcl-2 expression decreased with increasing DON concentrations, in contrast to Bax and Bid, which were increased with increasing DON concentration. These data demonstrate that DON induces apoptosis in PC12 cells through the mitochondrial apoptosis pathway.  相似文献   
4.
Animal behaviour can be viewed as a stream of elements, which, once accurately described, can be counted and timed. Data acquisition techniques and tools are reviewed, and some strategies for collection and analysis of data using PC computers are suggested. Automated instruments are not satisfactory for the study of complex behaviour and as such systemic observation remains irreplaceable. IBM PC-type computers, with a wide range of analytical software (e.g., spreadsheets, statistical packages, technical graphics), are practical for data acquisition. Several systems which can satisfy different applications are reviewed. Some systems can communicate with a videorecorder, a facility which remarkably increases the accuracy of measurement; this is essential for meaningful analyses of the internal structure of behavioural streams (sequences, time patterns) or communication processes. The power of new tools enables behavioural measurement with the necessary complexity to allow a whole new set of questions to be addressed. However, it also increases demands for meaningful content and analysis of data.  相似文献   
5.
The potential cytoprotective actions of a novel nicotinic agent 2,4-dimethoxybenzilidene anabaseine (DMXB) were investigated in differentiated PC12 cells and transected rat septal cholinergic neurons in vivo. In NGF-differentiated PC12 cells, removal of both NGF and serum led to cell loss, a reduced % of cells expressing neurites, the release of lactate dehydrogenase, and a decrease in total cellular protein. Cell loss was apparent within 24 h, and remained constant between 4–8 days post-NGF removal. NGF alone (100 ng/ml), DMXB (10 μM), but not nicotine (10 μM), prevented these cell and neurite losses. DMXB-induced cytoprotection was blocked by 1 μM mecamylamine. DMXB (1 mg/kg, ip) injected twice but not once per day protected cholinesterase-staining septal neurons from retrograde degeneration following unilateral fimbrial transections. The twice per day DMXB injection-protocol also decreased cell roundness among cholinesterase-staining cells in the lesioned septal hemisphere compared to saline-injected animals. These studies suggest that DMXB may exert cytoprotective activity in NGF-sensitive neuronal populations. © 1994 Wiley-Liss, Inc.  相似文献   
6.
We identified and characterized a neurodifferentiation compound from the marine brown alga Sargassum fulvellum collected from the Japanese coastline. Several instrumental analyses revealed the compound to be pheophytin a. Pheophytin a did not itself promote neurite outgrowth of PC12 cells. However, when PC12 cells were treated with a low concentration of pheophytin a (3.9 microg/ml) in the presence of a low level of nerve growth factor (10 ng/ml), the compound produced neurite outgrowth similar to that produced by a high level of nerve growth factor (50 ng/ml). Pheophytin a also enhanced signal transduction in the mitogen-activated protein kinase signaling pathway, which is also induced by nerve growth factor. The effect of pheophytin a on neurite outgrowth of PC12 cells was completely blocked by U0126, a representative mitogen-activated protein kinase kinase inhibitor. These results suggest that pheophytin a enhances the neurodifferentiation of PC12 cells in the presence of a low level of nerve growth factor and that this effect is mediated by activation of a mitogen-activated protein kinase signaling pathway.  相似文献   
7.
采用毛细管流交仪测定了PBT/PC共混物的表观粘度、剪切应力,观察了不同共混物组成和不同温度下共混物的流变行为,并借助扫描电镜对共混物和微观形态结构进行分析。结果表明:PBT/PC熔体共混物的流变行为接近假塑性流体.温度对共混物的流变行为影响很大,共混物的熔体粘度在PBT/PC为90/10和60/40时呈双极值.共混物为两相结构,PC含量为4-50%时呈两互锁结构。  相似文献   
8.
目的 观察利多卡因对 N-甲基-D-天冬氨酸(NMDA)抑制大鼠肾上腺嗜铬细胞瘤细胞(PC12细胞)增殖的影响。方法 将体外培养的 PC12细胞分为6组,分别采用正常不含药液的培养基(C组);含400μmol·L(-1)NMDA 的培养基(N组);NMDA 分别混合10μmol·L~(-1)(L_1组)、10~2μmol·L~(-1)(L_2组)、10~3μmol·L~(-1)(L_3组)以及10~4μmol·L~(-1)(L_4组)利多卡因的培养基培养5d,应用流式细胞仪测定细胞 DNA 相对含量,解析细胞周期,计算 S 期细胞荧光强度占受测细胞总荧光强度的百分数为 S期分数(SPF)和 S 期与 G_2期细胞荧光强度之和与 M 期细胞荧光强度的比值[(S G_2)/M]。结果 与C 组比较,N、L_1组 SPF 和(S G_2)/M 均降低(P<0.05),L_4组 SPF 降低(P<0.05),而 L_2及 L_3组 SPF和(S G_2)/M 差异无统计学意义(P>0.05)。与 N 组比较,L_2、L_3及 L_4组 SPF 和(S G_2)/M 升高(P<0.05),L_1组 SPF 升高(P<0.05),而(S G_2)/M 差异无统计学意义(P>0.05)。结论 NMDA 可以通过抑制 PC12细胞 DNA 合成而影响细胞的增殖活性,利多卡因能拮抗 NMDA 对 PC12细胞增殖的抑制作用。  相似文献   
9.
目的 克隆人野生型parkin基因并构建真核表达载体pCDNA3.1—parkin,将重组质粒转染PC12细胞获得高表达人野生型parkin基因的PC12细胞克隆。方法 从胎脑组织中提取总RNA,用RT—PCR方法获得人野生型parkin基因的全长cDNA,插入pCR2.1—TA克隆载体中进行序列测定,测序正确后将其亚克隆至表达载体pCD—NA3.1,利用脂质体将重组质粒转染PC12细胞,经G418筛选获得抗性细胞克隆,采用RT—PCR和Western Blot方法鉴定人野生型parkin基因在PC12细胞中的过表达。结果 经限制性内切酶酶切图谱分析和DNA序列测定证实目的基因已插入重组质粒,RT—PCR和Western Blot证明经G418筛选得到的转基因PC12细胞克隆中存在人野生型parkin基因的表达。结论 成功构建了人野生型parkin基因的真核表达载体,获得了稳定表达人野生型parkin基因的PC12细胞克隆,为进一步研究parkin的生物学功能以及parkin在帕金森病发病机制中的作用奠定了良好的基础。  相似文献   
10.
 Chromaffin cells of the adrenal medulla and their tumor counterparts, the pheochromocytoma (PC12) cells, are well-established model systems in neurobiology. The development of sympathoadrenal progenitor cells to chromaffin cells can be studied with regard to developmental signals which trigger the differentiation. With regard to potential treatments of neurological disorders like Parkinson’s disease chromaffin cell grafting can be used as one therapeutical approach. The beneficial effect of chromaffin cell grafts is possibly not only related to the release of dopamine but may also be linked to the release of growth factors. One of the growth factors that is synthesized by chromaffin and PC12 cells is basic fibroblast growth factor (FGF-2). The experimental data available so far, are in agreement with different functional roles of FGF-2. This article summarizes the putative physiological functions of FGF-2 in the adrenal medulla. Three differential functional roles of FGF-2 are discussed: (1) as a differentiation factor for sympathoadrenal progenitor cells; (2) as a target-derived neurotrophic factor for preganglionic sympathetic neurons which innervate adrenal medullary cells; (3) as an auto-/paracrine factor in the adrenal medulla. Accepted: 21 August 1996  相似文献   
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