环氧化酶-2抑制药对肺癌细胞和骨肉瘤细胞生长的抑制作用

目的观察选择性环氧化酶-2（COX-2）抑制药塞来昔布、罗非昔布对人骨肉瘤细胞株（HOS-8603）、肺癌细胞株（A-549）的作用以及罗非昔布、塞来昔布对两种细胞抑制效应的比较。方法MTT法测定体外培养的细胞株HOS-8603、A-549对不同浓度的罗非昔布和塞来昔布的敏感性，流式细胞仪分析细胞增殖周期的影响及凋亡。结果塞来昔布、罗非昔布均可明显抑制HOS 8603、A-549细胞的生长（P＜0.05），抑制效应呈现浓度依赖型和时间依赖型。HOS-8603和A-549细胞分裂阻滞在G2/M期，出现凋亡峰，塞来昔布对HOS 8603的作用强于罗非昔布。结论COX-2抑制药塞来昔布尼罗非昔布对骨肉瘤细胞、肺癌细胞的生长有抑制作用，有望成为抗肿瘤新药。     

扇贝多肽对UVB辐射小鼠胸腺淋巴细胞的保护作用

目的：研究扇贝多肽(polypeptide ftom Chlamys，farreri)对中波紫外线(UVB)辐射损伤小鼠胸腺淋巴细胞的保护作用。方法：UVB辐射小鼠胸腺淋巴细胞，MTT法检测胸腺淋巴细胞的活性；酶生化法检测细胞谷胱甘肽过氧化物酶(GSH-Px)、超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性；流式细胞术检测细胞内活性氧(ROS)的产生量以及细胞凋亡率。结果：PCF能明显减轻UVB辐射对小鼠胸腺淋巴细胞的损伤；提高细胞GSH-Px、SOD和CAT活性；降低细胞中ROS的产生量和细胞凋亡率。结论：PCF对小鼠胸腺淋巴细胞具有明显的辐射保护作用。     

Survivin在顺铂诱导Panc-1细胞凋亡中的作用

的 :体外观察顺铂是否具有诱导胰腺癌细胞株 (Panc-1)凋亡的作用 ,同时观察在此过程中凋亡抑制蛋白 Survivin的表达变化 ,为探讨胰腺癌的化疗耐药机制提供理论基础。方法 :用人 Panc-1株进行培养传代 ;MTT试验检测顺铂以不同浓度和不同时间对 Panc-1株生长的抑制作用 ;用 RT-PCR检测凋亡过程中 Survivin基因表达的动态变化。结果 :顺铂可明显抑制 Panc-1细胞增殖 ,其增殖抑制率呈浓度和时间依赖性 ;DNA电泳可以观察到凋亡的发生 ,而且呈药物浓度、作用时间依赖关系 ;Survivin表达水平随着顺铂作用浓度的增加而下降 ,当顺铂浓度为 5 0μg/ml时下降最明显 (61% ) ;Survivin c DNA/β-actin c DNA比值与细胞增殖抑制率和细胞凋亡率呈负相关 (P<0 .0 1)。结论 :顺铂可以有效诱导 Panc-1株的细胞凋亡 ,而且 Survivin基因的抑制在顺铂诱导 Panc-1株的细胞凋亡中起重要作用。     

大鼠神经干细胞的分离培养和分化鉴定

目的建立神经干细胞分离、培养和分化鉴定技术。观察神经干细胞生长、增殖特点。方法利用无血清培养,从胚胎大鼠海马、纹状体等区分离神经干细胞,进行体外扩增培养、传代观察。采用荧光免疫细胞化学检测技术,观察鉴定神经干细胞及其分化结果。结果从胚胎大鼠海马、纹状体等区分离的细胞具有增殖能力,可进行传代培养,获得的细胞克隆中有巢蛋白(nestin)表达阳性细胞,显微镜下观察见典型的干细胞特征。分化为3种神经细胞类型:神经元、胶质细胞、少突胶质细胞。结论用上述方法分离培养的神经干细胞具有自我更新和增殖能力,通过鉴定确为神经干细胞,并经过分化鉴定确认。     

益气清络方治疗类风湿关节炎的机制探讨

目的观察中药益气清络方对胶原性关节炎大鼠滑膜细胞产生的细胞因子的影响,探讨益气清络方治疗类风湿关节炎的机制。方法使用含药物血清的培养基培养胶原性关节炎大鼠滑膜细胞,用酶联免疫吸附试验(ELISA)法测定上清液中白细胞介素(IL)-1、肿瘤坏死因子(TNF)-α、基质金属蛋白酶(M M P)3、前列腺素E2(PGE2)的含量。结果益气清络方可以减少滑膜细胞产生的IL-1、TN F-α、PG E2的含量。结论益气清络方具有抗炎和调节免疫的作用。     

cyclinD1和CDK4在低氧心肌中的表达及意义

目的研究低氧心肌细胞周期及缺氧过程中细胞周期蛋白D1(cyclinD1)和细胞周期蛋白依赖激酶4(CDK4)表达的变化,探讨缺氧心肌在凋亡前是否存在增殖能力和自身修复。方法采用SD大鼠乳鼠进行心肌细胞培养,建立心肌缺血模型,实验分正常对照、缺血6 h和缺血12 h三组;以四唑盐比色试验(MTT)检测心肌细胞活力,流式细胞术测定细胞周期,免疫组化检测cyclinD1和CDK4表达。结果与对照组比较,心肌细胞缺氧处理6 h后,细胞周期中S 期比例增高(P<0 01),12 h后,S期比例下降(P<0 05);cyclinD1胞浆表达和CDK4 胞核表达增加。结论在缺氧所致死亡、凋亡过程中心肌细胞经历了一定程度的增殖过程,cyclinD1 和CDK4 表达增加参与了细胞增殖,缺氧损伤可刺激心肌细胞增殖能力。     

Rhodostomin inhibits thrombin-enhanced adhesion of ROS 17/2.8 cells through the blockade of alphavbeta3 integrin.

Osteosarcoma is a very malignant bone tumor which has a high metastatic potential and usually lead to poor prognosis. The adhesion of tumor cells to the endothelium or extracellular matrix (ECM) is an essential step in the metastatic cascade. We investigated the effect of thrombin on the adhesion activity of the osteosarcoma cell line, ROS 17/2.8. Incubation with the low concentrations of thrombin (0.01-5 U/ml, 5 min to 24 h) elevated the adhesion activity of ROS 17/2.8 to both human umbilical vein endothelial cells (HUVEC) and extracellular matrix, with the peak effect at the concentration of 0.5 U/ml for 30 min at 37 degrees C. The ROS 17/2.8 cells responded to thrombin by a peak effect of increased adhesion to HUVEC (5.5 folds vs. control) and fibronectin (4.8 folds) after thrombin pretreatment (0.5 U/ml, 30 min, 37 degrees C). Pretreatment with monoclonal antibodies against beta3 integrins, including anti-alphavbeta3, 10E5 and 7E3, effectively antagonized the thrombin-enhanced cell adhesion activity, whereas anti-alpha3beta1 and anti-alpha5beta1 did not antagonize the enhanced cell adhesion. Rhodostomin, an Arg-Gly-Asp (RGD)-containing snake venom peptide, and synthetic peptide RGDS also blocked the thrombin-enhanced ROS 17/2.8 cell adhesion. This study demonstrated that thrombin enhanced the cell adhesion of ROS 17/2.8 cells to HUVEC or ECM through an upregulation of beta3 integrins, and rhodostomin was a strong inhibitor on thrombin-enhanced cell adhesion, either to HUVEC or fibronectin substratum.     

A novel metalloprotease from Vipera lebetina venom induces human endothelial cell apoptosis.

A novel endothelial cell apoptosis inducing metalloprotease (VLAIP) was found in the snake venom of Vipera lebetina. This metalloprotease is a heterodimeric glycoprotein with molecular mass of about 106 kDa. The protease hydrolyzes azocasein, fibrinogen and oxidized insulin B-chain. The enzyme readily hydrolyzes the Aalpha-chain and more slowly Bbeta-chain of fibrinogen. VLAIP does not cleave fibrin. The complete amino acid sequences of the two different monomers of VLAIP are deduced from the nucleotide sequences of cDNAs encoding these proteins. The full-length cDNA sequences of the VLAIP-A and VLAIP-B encode open reading frames of 616 and 614 amino acids that include signal peptide, propeptide and mature metalloproteinase with disintegrin-like and cysteine-rich domains. VLAIP belongs to the metalloprotease/disintegrin family of reprolysins and has high identity with the proteins that induce apoptosis of endothelial cells. Treatment of HUVEC cells with VLAIP induces changes in the attachment of cells to the substrate and causes cell death. We demonstrated that VLAIP inhibits endothelial cell adhesion to extracellular matrix proteins: fibrinogen, fibronectin, vitronectin, collagen I, and collagen IV. The induction of apoptosis by VLAIP was shown by means of a typical DNA fragmentation pattern of apoptotic cells as well as by monitoring phosphatidylserine externalization using annexin V-FITC staining and flow cytometric analysis.     

丹芍化纤胶囊对体内外活化肝星状细胞增殖的影响

目的:研究中药复方制剂丹芍化纤胶囊对体内外活化肝星状细胞(HSCs)增殖的影响.方法:(1)体内实验:雄性Wistar大鼠57只分为正常组、模型组、治疗组.除正常组外,其余各组采用CCl4、饮酒、高脂低蛋白饮食等复合病因刺激制备肝纤维化动物模型8周,然后治疗组给予丹芍化纤胶囊(1g/kg体重)灌胃治疗8周.实验结束时部分大鼠用于测定肝功能及肝脏纤维化程度;部分用于分离HSCs,流式细胞仪检测细胞周期百分比.(2)体外实验:制备丹芍化纤胶囊大鼠药物血清;分离培养大鼠HSCs,并分为小牛血清组、正常大鼠血清组、丹芍化纤药物血清组,分别加入5%、10%、20%以上3种血清干预培养的HSCs,MTT比色法测定原代HSCs增殖情况.结果:(1)体内实验:治疗组较模型组肝功能、肝脏纤维化程度及HSCs增殖明显减轻.(2)体外实验:丹芍化纤药物血清组较同浓度小牛血清组、正常大鼠血清组明显抑制HSCs增殖,且此作用呈剂量依赖性.结论:丹芍化纤胶囊能显著抑制体内外HSCs增殖.