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121.
TGF-beta-1 gene transfer in joint cartilage cells. Stimulating effect in extracellular matrix synthesis 总被引:1,自引:0,他引:1
Möller HD Fu FH Niyibizi C Studer RK Georgescu HJ Robbins PD Evans CH 《Der Orthop?de》2000,29(2):75-79
TGF beta-1 has been shown to upregulate matrix synthesis in articular chondrocytes. TGF beta-gene transfer to chondrocytes has the potential to increase the local production of this key component within regenerating cartilage after trauma and could support the repair process in articular cartilage lesions. Primary rabbit articular chondrocytes were cultured and retrovirally transfected with the experimental TGF beta-1 and the lacZ marker gene for control purposes. After radioactive labeling of new synthesized matrix proteins results were compared with normal primary chondrocytes. After TGF beta-1 gene transfer the endogenous growth factor concentration was doubled compared to normal chondrocytes and decreased in the lacZ control group. The proteoglycan synthesis in TGF beta-1 transfected chondrocytes showed a 96% increase compared to the basal production of normal chondrocytes. The LacZ transfected group revealed the opposite effect by a 44% decrease. The collagen synthesis of TGF beta-1 transfected chondrocytes was 304% compared to normal chondrocytes, predominantly type II collagen. The lacZ group collagen production was reduced by 35%. We conclude that TGF beta-1 gene transfer overcomes the decreasing effect observed by transfection with the LacZ marker gene and increases matrix synthesis in articular chondrocytes. Genetically altered chondrocytes might improve the repair of cartilage lesions by stimulating matrix synthesis and supporting the expression of the hyaline phenotype. 相似文献
122.
Pelinkovic D Martinek V Engelhardt M Lee JY Fu F Huard J 《Zeitschrift für Orthop?die und ihre Grenzgebiete》2000,138(5):402-406
AIM: Muscle-based somatic gene therapy is a novel way to alleviate a biochemical deficiency. METHOD: Muscle-derived cells are very promising in the field of gene therapy and tissue engineering. First, most muscle tissue is accessible by injection. Second, muscle tissue consists of multinucleated, postmitotic myofibers, which enable a long-term expression of the transduced gene. Third, muscle tissue can be biopsied easily. It is available in abundance and the biopsy does not compromise the health and function of the patient. Finally, muscle tissue is highly vascularized, which makes systemic delivery feasible. RESULTS: Muscle-derived cells can promote muscle healing and bone healing. Implanted cells maintain a long-term transgene expression of therapeutic proteins. Isolated, muscle-derived stem cells can differentiate in osteoblasts. CONCLUSION: Based on these characteristics, we present four possible applications: inherited muscular diseases, muscle injury, bone healing, and intraarticular disorders. 相似文献
123.
124.
卫星搭载药用植物曼陀罗遗传变异的随机扩增多态性DNA分析 总被引:11,自引:0,他引:11
以曼陀罗种子为材料探讨太空环境对药用植物的影响。方法利用返回式卫星搭曼陀罗的种子,返回地面后播于实验田中,应用随机扩增多态性DNA(RNA(RAPD)分子标记技术分析不同组曼陀罗基因组的变异情况。结果从65个供试引物中筛选出15个能够产生可重复多态性增产物的引物。与地面对照组相比,失重组共产生39条多态性片段,基因组的多态性频率为23.1%,击中组共产生45条多态性片段,基因组的多态性频率为24. 相似文献
125.
三氧化二砷诱导人肿瘤细胞凋亡和G2+M期阻滞但引起人永 … 总被引:18,自引:0,他引:18
目的 研究 As2 O3引起肿瘤细胞凋亡和对细胞周期的影响。方法 采用 DNA凝胶电泳 ,流式细胞仪分析、RT- PCR和 Western免疫印迹等技术检测细胞凋亡的发生。结果 由 As2 O3诱导的人肺腺癌 GL C- 82、胃腺癌 MGC- 80 3和 SGC- 790 1、食管癌 Ec10 9、宫颈癌 He L a细胞凋亡前 ,细胞阻滞在 G2 M期 ,上述细胞均表现为对c- myc基因的下行调节 ;但在导致永生化人宫颈上皮 HCE16 /3细胞凋亡之前 ,细胞却被阻滞在 G1期 ,对 c- m yc基因表达无影响。结论 As2 O3引起细胞凋亡与细胞周期阻滞有关 ,在肿瘤细胞和前恶变的 HCE16 /3细胞中阻滞的时期不同 ,这可能与 c- myc基因表达的改变与否有关 相似文献
126.
Acute total occlusion of the left main coronary artery is usually characterized by a rapid course of deterioration that challenges therapeutic intervention. Unlike subtotal occlusion of the left main coronary artery, acute total occlusion of the left main coronary artery is extremely rare and has a grave prognosis. Most patients with this problem die suddenly or go into cardiogenic shock. Direct percutaneous transluminal coronary angioplasty (PTCA) was performed on 2 patients, both suffering from cardiogenic shock due to acute total occlusion of the left main coronary artery. Both patients underwent coronary artery bypass surgery subsequently. One patient, who had substantial intercoronary collaterals, remained asymptomatic at 31 months of follow-up. The other, who had no intercoronary collateral circulation, expired 3 days after coronary artery bypass surgery. We conclude that direct PTCA to the acutely occluded unprotected left main coronary artery in cardiogenic shock patients is a potentially life-saving procedure, and the presence or absence of collaterals from the dominant right coronary artery will influence the clinical outcome. 相似文献
127.
Wang Kuojian Zhao Fuyuan Han Hongli et alDepartment of Thoracic Surgery Tianjin Chest Hospital Tianjin 《中国肿瘤临床》1998,(7)
共施行纵隔镜检查术127例,诊断符合率达87%。纵隔镜检查术对某些累及纵隔淋巴结的疾病或紧邻纵隔的胸部疾病是一种有效的检查方法,尤其适合诊断不明之单纯纵隔淋巴结肿大者。对肺癌伴有纵隔淋巴结肿大或纵隔肿瘤者可选择应用 相似文献
128.
To evaluate the steno-occlusive changes in the external carotid system in moyamoya disease, cerebral angiograms of 39 moyamoya patients were retrospectively reviewed. There were 26 females and 13 males, age ranged from 4 to 62 years with a mean of 26 years. Initial symptoms were ischaemia in 27 patients, haemorrhage in 9, and none in 3. Stenosis, occlusion, and dilatation in the external carotid system were analysed angiographically. No stenosis or occlusion of the superficial temporal artery, middle meningeal artery, or occipital artery was observed in either preoperative or postoperative follow-up angiograms in any patients. Steno-occlusive changes do not occur in the external carotid system, but are confined in the internal carotid system in moyamoya disease. 相似文献
129.
Evolution in the treatment of choledochus cyst 总被引:3,自引:0,他引:3
PURPOSE: The aim of this study was to reevaluate the results of the short jejunal interposition (Chicago-Beijing procedure) in the treatment of choledochus cyst and search for the way of further improvement. METHODS: A retrograde study of some 500 surgical cases was made. The immediate postoperative and 10-year follow-up results of the 3 main procedures used in 3 different time periods were compared. Twenty-five redo cases of the above-mentioned series and another 6 referred from other hospitals were analyzed specially for the main cause of complications. RESULTS: Ten-year uneventful follow-up occurred in more than 90% of cases after the Chicago-Beijing procedure, which was evidently superior to other 2 kinds of methods. Having solved the problems of the abnormal pancreatico-biliary communication and entero-biliary reflux, it remains the challenge of the anastomosis stricture. Malignancy degeneration disappeared dramatically after total excision of the cyst. CONCLUSIONS: Chicago-Beijing procedure proved to be the most reliable operation for choledochus cyst in comparison with the other 2 conventional methods in BCH. The prevention of anastomosis stricture should be emphasized for the further improvement of the surgical result. 相似文献
130.
Identification and Determination of Microcystins in Source Water an Waterbloom Sample From Meiliang Bay, Taihu Lake, China 总被引:1,自引:0,他引:1
OBJECTIVE: To identify and determine the congener and level of microcystins in the source water of Taihu Lake. METHODS: Improved method of SPE combined with HPLC was employed to detect the concentration and varieties of microcystins in source water and bloom samples collected from Meiliang Bay, Taihu Lake. RESULTS: The contents of two predominant microcystin components, MC-RR, and MC-LR, were relatively high in samples during warm months and correlated with the phase of algae growth. The maximum concentrations of MC-RR and MC-LR in water sample reached 3.09 +/- 0.53 microg/L and 2.39 +/- 0.41 microg/L during the period of water bloom in September 2004, respectively. Even without waterbloom, the concentration of MC-LR in source water sample was still higher than the guideline value. CONCLUSION: The status of microcystin pollution in this region is serious and measures to monitor and control the growth of cyanobacteria are urgently needed. 相似文献