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41.
Objective To test the hypothesis that p53 gene therapy combined with endostatin can enhance tumor response to radiation therapy of RM-1 mouse xenograft prostate cancer and to investigate its mechanism. Methods A mouse prostate cancer model was established. Then mice with xenograft tumor were randomly divided into group A (control), B (radiation), C (radiation and rAdp53), D (radiation and rh-endostatin) and E (radiation and rAdp53 and rh-endostatin). On day 1, rAdp53 was injected intra-tumorously with 1 × 1010 vp per animal to group C and E. From day 1 to 14, rh-endostatin was given 15 mg/kg intraperitoneally daily to group D and E. On day 4 single fraction of 15 Gy was given to tumors in groups B, C, D and E. Normal saline was injected intra-tumorously or intraperitoneaUy accordingly as control. No treatment was done to group A. Tumor volume was measured daily. Samples were collected on Days 5, 10 and 15. Ki67, CD31, p53 and VEGF were detected by means of immunohistochemistry. Results (1) Radiation alone, radiation combined with intra-tumorous injection of Adp53 and/or intraperitoneal injection of rh-endostatin resulted in tumor growth arrest of RM-1 cells in vivo (P = 0.000). Radiation combined with both rAdp53 and rh-endostatin was the most effective treatment (P < 0.05). (2) All the four treatment groups had a decreased expression of mutant type P53 (P = 0.000). The expression of Ki67 in groups B and C were equal (P 0.05) and increasing (P = 0.000), respectively. Group D had a up-down-up curve (P < 0.05), but group E had a up-down one. On day 5 the expresion of VEGF in group E was the lowest (P < 0.05). An increased expression of MVD compared with the control was shown, and MVD in groups C, D and E were always higher than that in the control (P < 0.05). Conclusions The limitation of radiotherapy could be overcome by combination with beth p53 gene therapy and endostatin on the growth of mouse prostate cancer cell. Radiation, rAdp53 and endostatin have their own role but they can be interacted with each other. 相似文献
42.
Lin Bo Wang Jian Guo Shen Li Feng Dong Chao Yang Xu Wen Jun Chen Shu Duo Xie Xiang Yang Song Ning Dai Xiao Ming Yuan 《Journal of gastrointestinal surgery》2008,12(8):1359-1363
We previously reported that lymphatic mapping using isosulfan blue can be used to identify sentinel nodes (SNs). This study
was undertaken to evaluate the feasibility of using the SN technique in treating early gastric cancer and to explore its usefulness
for minimal invasive surgery. Twenty-three patients with early gastric cancer who underwent SN biopsy were retrospectively
evaluated. Based on SN evaluation, individualized surgery was performed in five patients with T1N0M0 gastric cancer. When
pathological examination of frozen sections revealed metastasis in SNs, we performed a standard D2 gastrectomy. Laparoscopic
local resection was applied when the SN biopsy was negative. Our results showed that the success rate with SN biopsy in early
gastric cancer was 100%, as were the accuracy, sensitivity, and specificity. All five patients with early gastric cancer had
SNs negative for metastases both by frozen section and by postoperative pathology. Thus, all these patients underwent laparoscopic
local resection without extended lymphadenectomy. We conclude that SN biopsy is a useful tool to individualize the operative
procedure, and laparoscopic local resection can be safely performed using SN guidance in selected patients with early gastric
cancer. 相似文献
43.
背景:与小肠黏膜下层等材料相比,脱细胞血管具有天然管状结构,与输尿管形态结构相近,替代输尿管时仅需端端吻合即可,手术操作简单,血管外壁光滑,获取及制备方法简便等优点。
目的:拟应用同种颈动脉血管无细胞基质体外构建输尿管。
设计、时间及地点:观察性实验,于2006-09/2008-06在上海交通大学医学院附属新华医院动物实验中心完成。
材料:长风杂交白猪由上海松联实验动物公司提供。上海交通大学医学院实验动物中心提供的健康成年大鼠8只,用于血管无细胞基质的动物毒性实验。
方法:剥去猪颈动脉血管外膜,PBS冲洗若干遍,然后将血管置于pH 7.1 的PBS中4 ℃下振荡清洗,0.5%十二烷基硫酸钠振荡24 h,后使用双蒸水4 ℃下反复振荡洗涤1周,每日换双蒸水2次。对于解剖过程中肌肉残留相对稍多的血管,在双蒸水洗涤前以混合消化液37 ℃下振荡消化约2 h,再行双蒸水洗涤。制备的无细胞基质置于青、链霉素溶液中,4 ℃保存,完成脱细胞支架制备。
主要观察指标:光镜及电镜观察脱细胞后管壁无细胞基质片的主要成分。将同种异体来源内皮祖细胞培养增殖后植入血管无细胞基质,观察细胞生长情况,并进行血管无细胞基质动物毒性实验。拉力实验了解血管无细胞基质材料的收缩性能。
结果:颈动脉血管无细胞基质中已无细胞成分,无细胞基质主要由胶原成分组成。扫描电镜未见该材料表面存在细胞及细胞碎片,同时发现该无细胞基质存在孔隙样结构。体外同种异体来源的内皮祖细胞培养增殖后植入血管无细胞基质,细胞黏附于无细胞基质。血管无细胞基质按毒性分级属于无毒级。拉力实验说明该无细胞基质具有一定的韧性和牵张性。
结论:采用胰酶和十二烷基硫酸钠制备的颈动脉血管无细胞基质材料无细胞残留,具有一定的韧性和牵张性,种植于其中的种子细胞具备一定的生长能力。 相似文献
44.
45.
Expression of Anion Exchanger 1 Sequestrates p16 in the Cytoplasm in Gastric and Colonic Adenocarcinoma 下载免费PDF全文
Wei-Wei Shen Jun Wu Li Cai Bing-Ya Liu Yan Gao Guo-Qiang Chen Guo-Hui Fu 《Neoplasia (New York, N.Y.)》2007,9(10):812-819
p16INK4A (p16) binds to cyclin-dependent kinase 4/6 and negatively regulates cell growth. Recent studies have led to an understanding of additional biologic functions for p16; however, the detailed mechanisms involved are still elusive. In this article, we show an unexpected expression of anion exchanger 1 (AE1) in the cytoplasm in poorly and moderately differentiated gastric and colonic adenocarcinoma cells and in its interaction with p16, thereby sequestrating the protein in the cytoplasm. Genetic alterations of p16 and AE1 were not detectable. Forced expression of AE1 in these cells sequestrated more p16 in the cytoplasm, whereas small interfering RNA-mediated silencing of AE1 in the cells induced the release of p16 from the cytoplasm to the nucleus, leading to cell death and growth inhibition of tumor cells. By analyzing tissue samples obtained from patients with gastric and colonic cancers, we found that 83.33% of gastric cancers and 56.52% of colonic cancers coexpressed AE1 and p16 in the cytoplasm. We conclude that AE1 plays a crucial role in the pathogenesis of gastric and colonic adenocarcinoma and that p16 dysfunction is a novel pathway of carcinogenesis. 相似文献
46.
47.
目的应用显微手术夹闭、血管内栓塞和栓塞后手术夹闭3种治疗方法,探讨治疗颅内破裂动脉瘤的安全有效方案。方法显微手术瘤颈夹闭30个动脉瘤,栓塞34个动脉瘤,栓塞后夹闭15个动脉瘤。结果夹闭组30个完全夹闭,无复发,死亡率6%(2/30)。栓塞组完全闭塞率70.6%(24/34),复发率17.6%(6/34),死亡率11.8%(4/34)。栓塞后手术组15个完全夹闭,无复发,死亡率6.7%(1/15)。治疗结束用GOS评价,1个月后3组良好率分别为80.0%、79.4%和80.0%;半年后良好率分别为90.0%、88.2%和86.7%。结论显微手术瘤颈夹闭术仍然是治疗破裂动脉瘤的有效方法,具有1次治疗彻底和复发率低的优势,并可作为栓塞失败的补救手段。 相似文献
48.
49.
目的观察针刺推拿中药综合治疗颈性眩晕的疗效。方法设综合组80例、电针组42例、推拿组68例和中药组36例,进行疗效比较分析。结果综合组有效率为93.8%,电针组有效率为73.8%,推拿组有效率为86.8%,中药组有效率为69.4%,综合组有效率与其他几组比较差异均有统计学意义(P〈0.05)。结论采用电针、推拿、中药相结合的综合疗法治疗颈性眩晕集诸单一疗法之精华,避免单一疗法的局限性,可提高有效率。 相似文献
50.
真皮-脂肪颗粒混合液注射移植修复面部凹陷性组织缺损 总被引:2,自引:0,他引:2
目的探索一种新的面部凹陷性组织缺损的修复方法。方法将真皮颗粒和脂肪颗粒混合制成真皮-脂肪颗粒混合液,用2mm脂肪抽吸针注射移植修复面部凹陷性组织缺损。结果本组18例,17例1次填充成功,仅1例因缺损面积过大而补充填充1次,全部病例伤口均Ⅰ期愈合,无感染,外形明显改善。结论真皮-脂肪颗粒混合移植修复面部凹陷性组织缺损,手术简单易行,术后吸收少,效果较好,值得推广。 相似文献