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71.
Objective To explore the mechanisms of cytokines on acute radiation disease in irradiated beagles.Methods The sera of beagles irradiated with 4.5 Gy γ-rays with cytokines treatment was collected at different time points post irradiation.The two-dimensional gel electrophoresis(2-DE)was used to isolate and compare the differentially expressed proteins in sera.HD-MS was used to analyze the differentially expressed proteins with significance,and the amino acid sequences should be determined. Results High resolution 2-DE gel map was obtained.There were six differentially expressed proteins in sera of irradiated beagles at different time points.Four protein spots were successfully identified by MS.A significant spot was identified as serum amyloid A(SAA)by HD-MS,with relative molecular mass of 13 077 and isoelectfie point of 6.26.Expression of SAA was not found 1 d pre-irradiation and 36 d postirradiation,but increased slightly 1 d(0.2166)and significantly 14 d post-irradiation(0.4577). Conclusions The expression of serum amyloid A was consistent with the process of acute radiation injury,which might indicate the turnover of the disease.  相似文献   
72.
Objective To explore the clotting mechanism in beagles irradiated by 4.5 Gy γ-rays after treatment with supportive care,or supportive care and combined cytokines.Methods Sixteen beagles were divided into irradiation control group,Supportive care group and combined cytokines treatment group.Platelet aggregation test,thrombelagtography (TEG) and the time measurement were analyzed in vitro.Results In irradiation group and supportive care group,the platelet aggregation rates in beagles were decreased markedly and the k value of TEG was increased 7 d post-irradiation,while those indexes in combined cytokines treatment group changed little.At 14 d post-irradiation,each parameter of TEG in irradiated group changed obviously.The values of r,k,r+k and M were elevated significantly,clotting time and the maximum coagulation time of thrombus delayed,the Ma value was decreased markedly,and the maximum elasticity amplitude of thrombus was diminished.All parameters in combined cytokines treatment group were better than those in supportive care group.The thrombin time was prolonged obviously in irradiated group 14 d post-irradiation,while the thrombin time was the longest at 2-3 weeks post irradiation in supportive care group and combined cytokines treatment group(P>0.05).Conclusions Cytokines could improve the platelet aggregation and the blood clotting functions of beagles suffering from acute radiation sickness.  相似文献   
73.
目的:研究腺病毒介导的E1A基因(Ad-E1A)体外对Hep-2人喉癌细胞、A375人黑色素瘤细胞、SMMC-7721人肝癌细胞的生长抑制作用及敏感程度。方法:RT-PCR鉴定E1A基因的转录;MTT法检测细胞的生长抑制作用;Hoechst染色法检测细胞核形态改变;流式细胞术(FCM)检测细胞周期和细胞凋亡。结果:Ad-E1A在三种癌细胞内均有效表达,在其感染72h和96h后对Hep-2、A375、SMMC-7721细胞的生长抑制率达分别为18.65%和29.95%;33.02%和45.36%;36.32%和54.11%;其中对SMMC-7721细胞的作用最强,FCM 检测发现其凋亡率为36.92%。Hoechst染色表明Ad-E1A诱导肿瘤细胞凋亡,使其呈现典型的核固缩、断裂并出现凋亡小体等核形态改变。结论:Ad-E1A对Hep-2、A375、SMMC-7721三种癌细胞均有生长抑制作用,尤以对SMMC-7721细胞作用最强、A375细胞次之, Hep-2细胞的敏感性相对较低;此外,Ad-E1A还能诱导肿瘤细胞凋亡。  相似文献   
74.
目的研究腺病毒介导的ING4基因(简称Ad-ING4)体外对人前列腺癌细胞PC-3的生长抑制作用。方法将携有绿色荧光蛋白(GFP)的腺病毒空载体Ad(简称Ad-GFP)及Ad-ING4分别感染PC-3细胞,RT-PCR检测ING4基因的转录;荧光显微镜观察Ad-ING4对PC-3细胞的细胞毒作用;用MTT比色法绘制细胞生长曲线,计算生长抑制率;流式细胞仪(FCM)检测Ad-ING4对细胞凋亡的影响;Hoechst 33258核荧光染色检测细胞凋亡的核形态学变化。结果 RT-PCR显示Ad-ING4能在PC-3细胞内转录;MTT结果提示Ad-ING4感染72 h和96 h后对细胞生长抑制率达39.29%和50.00%;FCM检测Ad-ING4感染细胞72 h后凋亡率为76.19%;核荧光染色结果进一步证明Ad-ING4对PC-3细胞可呈现典型的细胞凋亡核形态学改变。结论 Ad-ING4能够明显抑制PC-3细胞的生长,并诱导细胞凋亡。  相似文献   
75.
Objectivc To observe the therapeutic effects of combined cytokines on hematopoietic injuries induced by 4.5 Gy60 Co γ-rays irradiation in beagles,and to provide experimental evidences for the clinical treatment of extremely severe myeloid acute radiation sickness(ARS).Methods 16 beagles were given 4.5 Gy60 Co γ-rays total body irradiation,and then randomly assigned into irradiation control group,supportive care group and cytokines group.In addition to supportive care,recombinant human granulocyte colony-stimulating factor (rhG-CSF),recombinant human interleukin-11(rhIL-11)and recombinant human interleukin-2(rhIL-2)were administered subcutaneouly to dogs in cytokines group.Peripheral blood hemogram was examined once every two days.Bone marrow and peripheral blood were collected to proceed colony cultivation 4 d pre-irradiation and 1 and 45 d post-irradiation.Conventional histopathological sections of sternum were prepared to observe the histomorphology changes. Results After irradiation,the population of all kinds of cells in peripheral blood declined sharply.WBC nadir Was elevated(1.04×109/L,but 0.28×109/L and 0.68×109/L for the irradiation control group and the supportive care group separately),the duration of thrombocytopenia was shortened (24 days,but 33 days for the supportive care groug) and red blood cell counts were maintained in the range of normal values after cytokincs treatment in combination.The colony forming efficiency of haemopoietic stem cells(HSCs)in bone marrow and peripheral blood decreased obviously 1 d post irradiation,but recovered to the level of that before irradiation 45 d post irradiation after supportive care and cytokines treatment.Hematopoietic cells disappeared in bone marrow of animals in irradiation control group,but hematopoietic functions were recovered after cytokines were administrated.Conclusions RhG-CSF.rhIL-11 and rhIL-2 used in combination could elevate WBC nadir,accelerate the recovery of leukocytes,platelets and red blood cells and promote the proliferation,differentiation and maturity of HSPCs left in the body after 4.5 Gy γ-rays total body irradiation,eventually restore the hematopoietic function.Hence,combination of rhG-CSF,rhIL-11 and rhIL-2 could serve as better therapeutic strategy to treat extremely severe myeloid ARS.  相似文献   
76.
再生丝素膜对鼠胚真皮层成纤维细胞生长的影响   总被引:4,自引:0,他引:4  
目的 研究再生丝素膜对鼠胚真皮层成纤维细胞生长的影响。方法 采用静置贴壁培养法在再生丝素膜上体外培养鼠胚真皮层成纤维细胞,并用活细胞计数法及MTT比色法观察再生丝素膜对细胞的形态、功能和生长的影响。结果 再生丝素膜对鼠胚真皮层成纤维细胞的贴壁能力和形态及其代谢功能未见明显改变,也未见明显毒性,并能支持细胞正常生长,呈现正常的生长繁殖曲线。结论 再生丝素膜对鼠胚真皮层成纤维细胞具有良好的细胞相容性。  相似文献   
77.
报告用MIT比色法观察了恶性肿瘤、SLE、哮喘等疾病患者的NKCF活性,并与经PHA刺激的淋巴细胞~3H—TdR 掺入量(cpm)和刺激指数(SI)对比。结果;(1)三类恶性肿瘤患者的NKCF 活性比正常值明显降低,而他们的淋巴细胞cpm 和SI 则与正常值无显著差异;(2)SLE 组NKCF 活性显著下降,而淋巴细胞cpm 和SI 有所上升;(3)哮喘患者的NKCF 活性无明显改变,而淋巴细胞cpm 和SI 升高。结果表明,NKCF 活性检测对恶性肿瘤和SLE 有辅助诊断价值。  相似文献   
78.
目的:通过汗防已甲素联合塞来昔布逆转白血病细胞耐药的实验研究,探讨有关多药联合逆转肿瘤细胞的耐药机制.方法: 噻唑蓝(MTT)比色法检测汗防已甲素联合塞来昔布对K562细胞的细胞毒试验;用流式细胞技术(FCM)检测各组K562细胞内的药物浓度;用FCM检测各组的早期凋亡(Annexin Ⅴ);用RT-PCR检测各组COX-2/COX-1的表达.结果: 汗防已甲素联合塞来昔布对K562细胞的抑制作用与其他组相比有显著性差异(P〈0.05);细胞内的药物浓度高于其他实验组;诱导凋亡率(17.67%)高于其他实验组;COX-2/COX-1的表达明显低于其他实验组.结论: 汗防已甲素联合塞来昔布逆转K562细胞的效果明显,能够增加K562细胞内药物浓度,诱导细胞凋亡,降低 COX-2/COX-1的表达.  相似文献   
79.
人Epsilon干扰素在CHO细胞中的表达及生物学活性的研究   总被引:2,自引:1,他引:2  
目的 为了研究新发现的人epsilon干扰素(hIFN-ε)的生物学活性,我们通过RT-PCR克隆了hIFN-ε基因,并构建pcDNA3.1/myc-his(-)A-hIFN-ε(以下简称pcDNA3-1A-hIFN-ε)的真核表达载体,在CHO细胞中表达,并研究真核细胞重组表达的rhIFN-ε的生物学活性。方法 用TNF-α刺激人宫颈癌HeLa细胞,抽提总RNA,经RT-PCR获得全长cDNA,与pcDNA3.1/myc-his(-)A真核表达载体连接,构建重组体pcDNA3.1A-hIFN-ε并在CHO细胞中进行表达,采用微量细胞病变抑制试验研究表达产物中的rhIFN-ε对多种病毒的抗病毒活性;MTT法检测其对A375、HeLa和A549细胞的生长影响,并通过在Wish、HeLa、A375细胞中诱导MxA抗病毒蛋白的产生研究hIFN-ε的抗病毒机制。结果 经PCR和限制性酶切鉴定以及DNA测序,结果表明已经成功构建了重组体pcDNA3.1A-hIFN-ε,并在CHO细胞中稳定表达了rhIFN-ε蛋白,该蛋白具有抗HSV-I、PolioV、Ad3和VSV病毒的作用,能够抑制HeLa、A375、A549细胞的生长,刺激Wish、HeLa、A375细胞产生MxA蛋白。结论 本研究成功地构建了pcDNA3.1A-hIFN-ε真核表达载体并在CHO细胞中获得稳定表达,证明了ddFN.£蛋白具有抗病毒和抗增殖活性,其抗病毒效应的分子机理可能与诱导细胞产生MxA抗病毒蛋白有关,为今后研究rhIFN-ε的生物学功能和基因重组药物研制及其开展基因治疗奠定了基础。  相似文献   
80.
脐血LAK与CIK细胞杀伤活性研究   总被引:4,自引:0,他引:4  
寻求一种可用于过继免疫疗法的高效免疫活性细胞。方法用多种细胞因子诱生CIK细胞,用MTT法测定LAK和CIK细胞杀伤活性。结果在峰值期CIK细胞杀伤活必均显著高于LAK细胞。  相似文献   
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