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101.
Mechanical loading is an important factor regulating cartilage metabolism maintained by chondrocytes. However, some of its underlying mechanisms remain poorly understood. In this study, we employed a chondrogenic cell line ATDC5 to investigate roles of P2Y2 and GRK2 in chondrocyte mechanotransduction. We first confirmed the expression of chondrocyte markers in differentiated ATDC5 cells. We then exposed both differentiated and undifferentiated ATDC5 cells to oscillatory fluid flow, and found that differentiated ATDC5 cells responded to oscillatory fluid flow by increasing COX‐2 and aggrecan expressions. More importantly, fluid flow induced ERK1/2 response in differentiated cells was increased more than 10 times compared to those in undifferentiated cells. Furthermore, we found that P2Y2 mRNA and protein levels in differentiated ATDC5 cells were significantly higher than those in undifferentiated cells. In contrast, GRK2 protein levels in differentiated cells were significantly lower than those in undifferentiated cells. Finally, overexpressions of P2Y2 and GRK2 in differentiated ATDC5 cells result in a 34% increase and a 21% decrease of the ERK1/2 phosphorylation, respectively, in response to oscillatory fluid flow, suggesting important roles of P2Y2 and GRK2 in chondrocyte mechanotransduction. © 2010 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29:828–833 相似文献
102.
Objective: To investigate the effect of timing of surgery on clinical results and perioperative complications in pediatric patients with Gartland III type supracondylar humeral fractures without neurovascular compromise. Methods: Eighty‐six c onsecutive children treated surgically at our hospital from April 2005 to June 2007 for displaced supracondylar humeral fractures were reviewed. All these patients were treated by the same group of doctors. The children were divided into two groups: early if treated within 12 hours after injury and delayed if treated later than that. Perioperative complications and clinical results, especially for open surgery, were compared between the two groups. Results: Forty pediatric patients underwent surgery in the early group and 46 in the delayed group. There were no significant differences between the two groups in perioperative complications such as pin tract infection, iatrogenic nerve injury, compartment syndrome and conversion to open surgery. For open surgery, both the clinical results and perioperative complications were not affected by delaying for more than 12 hours after injury. However, blood loss and operation time were greater in the early than in the delayed group, possibly due to relatively more edema. Conclusion: Delay in surgery, regardless of whether it is closed or open, for more than 12 hours after injury does not influence the perioperative complications and clinical results for displaced supracondylar humeral fractures in children. However early open reduction and pinning may increase intra‐operative blood loss and take longer. 相似文献
103.
The hallmark of IgA nephropathy (IgAN) is the mesangial deposits of polymeric IgA. However, the source of IgA1 and the mechanism of deposition of IgA1 in the mesangium remain unknown. To better understand its pathogenesis, we investigated the expression of CD19(+)CD5(+)B cells and IgA1-positive cells in the tonsils of IgAN patients. Immunofluorescence was used to visualize the locations of CD19(+)CD5(+)B cells and IgA1-positive cells in the tonsils. In this study, it was demonstrated that CD19(+)CD5(+)B cells are usually found in germinal centers and in the capsule covering the upper parts of the nodules of lymphoid tissue (cap of the nodule). The expression of IgA1-positive cells in tonsil tissue can be seen in the cap of the nodule and subepithelial tissue. There is a significant relationship between IgA1 and CD19(+)CD5(+)B cells. The level of CD19(+)CD5(+)B cells is positively correlated to the severity of renal pathological changes. These findings suggest that CD19(+)CD5(+)B cells in the tonsils could have an impact on the pathogenesis of IgAN. 相似文献
104.
目的探讨全膝关节置换(TKA)术后患者髌骨位置、活动度的变化以及其对膝关节功能和活动的影响.方法 自1998年9月至2006年6月在上海交大医学院附属第九人民医院收治的205例初次TKA患者中选取资料完整、获得良好随访的51例患者(62个膝关节),平均随访时间38.7个月,对其进行髌骨高度、倾斜角及侧方移动度进行测量,与术前对照,并与膝关节活动度做相关性统计分析,综合研究髌骨方面对膝关节功能影响的关键因素.结果 (1)TKA术后髌骨高度较术前下降,差别有统计学意义(P〈0.01),髌骨外翻倾斜角减小;(2)髌腱短缩〉 10%时,其短缩程度与膝关节活动度呈负相关(r=-0.79,P〈0.01);(3)髌骨活动度与膝关节活动度呈正相关(r=0.53,P〈0.01).结论 (1)TKA术后髌韧带存在一定程度的短缩,髌骨不存在明显外翻;(2)髌骨位置及髌骨活动度影响膝关节功能:当髌腱短缩〉10%时,髌骨位置越低,膝关节活动度越小,膝关节功能越差;髌骨活动度越差,膝关节活动度越小. 相似文献
105.
[目的]探讨骨形态发生蛋白诱导的大鼠成肌细胞应用于组织工程化人工骨修复大鼠胫骨缺损的效果。[方法]32只体重在200~250 g的雄性SD大鼠随机分成4组,每组8只。A组:聚乙烯管内植入诱导2周的成肌细胞复合透明质酸钠。B组:聚乙烯管内植入成肌细胞复合透明质酸钠。C组:聚乙烯管内植入透明质酸钠。D组:聚乙烯管内注入生理盐水。术后12周,进行X线观察、大体观察、组织学观察(HE染色)以及四环素和钙黄绿素标记。[结果]术后12周时大体观察发现,A、B组骨缺损处可见大量类骨样组织填充,未触及反常活动,C、D组可见少量胶冻样组织及类骨样组织填充,无反常活动。X线观察可见A和B组骨痂吸收,髓腔再通,C、D组有少量新骨痂,髓腔未通。组织学观察可见A和B组有大量新生骨小梁,四环素和钙黄绿素染色可见黄绿色荧光。[结论]初步结果显示经诱导的大鼠成肌细胞可作为骨组织工程的种子细胞,用于修复骨缺损。 相似文献
106.
Study Type – Therapy (case series) Level of Evidence 4 What’s known on the subject? and What does the study add? Although extranodal extension in node‐positive patients may provide prognostic information in certain urological malignancies, contradictory results have been reported in node‐positive patients after radical cystectomy for bladder cancer. We examined whether extranodal extension could have an impact on the outcomes of node‐positive patients who underwent radical cystectomy for bladder cancer in a single large tertiary hospital. We have shown that the presence of extranodal extension was not an independent prognostic factor in node‐positive patients after radical cystectomy and pelvic lymphadenectomy for bladder cancer.
OBJECTIVE
? To examine whether extranodal extension (ENE) has an impact on the outcome of node‐positive patients who underwent radical cystectomy for bladder cancer.PATIENTS AND METHODS
? Of 543 consecutive patients who underwent radical cystectomy for urothelial carcinoma of the bladder between 1990 and 2007, 112 patients with lymph node metastasis detected on histological examination were evaluated with regard to recurrence‐free survival (RFS) and disease‐specific survival (DSS) based on ENE status.RESULTS
? The overall 5‐year RFS and DSS rates were 22.3% and 33.8%, respectively. ENE was observed in 41 (36.6%) of the 112 patients. ? The presence of ENE was associated with advanced pathological nodal status (P= 0.004), more positive lymph nodes (P= 0.006), and higher lymph node density (P < 0.001). ? The incidence of positive ENE increased with large positive lymph node diameter (P < 0.001). ? Multivariate analysis showed that lymph node density (hazard ratio (HR) = 2.39, 95% CI 1.09–5.24, P= 0.029; and HR = 3.13, 1.43–6.84, P= 0.004) and use of adjuvant chemotherapy (HR = 1.80, 1.02–3.20, P= 0.041; and HR = 2.07, 1.13–3.79, P= 0.018) were significant predictors of RFS and DSS, respectively. ? After adjustment for other prognostic factors, ENE was not significantly related to RFS (P= 0.825) and DSS (P= 0.961) by multivariate analysis.CONCLUSIONS
? The presence of ENE was not an independent prognostic factor in node‐positive patients after radical cystectomy for bladder cancer. ? Additional prospective studies are needed to determine the independent prognostic role of ENE. 相似文献107.
理气扶正中药对运动大鼠内分泌功能的影响 总被引:11,自引:0,他引:11
观察了理气扶正中药对7周递增负荷跑台训练的雄性大鼠内分泌功能的影响。结果显示:一般训练和强化训练均未导致大鼠生殖内分泌功能的抑制;强化训练运动后大鼠血皮质酮水平升高,理气扶正中药能使强化训练运动后24小时血睾酮、游离睾酮和FSH水平升高。结果表明理气扶正中药促进此状态下的内分泌功能,结合以往我们运用补肾助阳中药改善运动内分泌功能紊乱的研究,以及中医关于肝肾关系的学说,进一步为中药在运动机体的科学应用提供参考 相似文献
108.
荧光示踪法研究逆行岛状皮瓣静脉回流 总被引:3,自引:0,他引:3
目的探讨采用荧光示踪法研究逆行岛状皮瓣静脉回流的可行性,并初步观察静脉回流规律。方法20只新西兰大白兔,每只取耳静脉血0.ImL,分离RBC并用FITC标记。流式细胞仪检测已标记的RBC阳性率及荧光强度,倒置荧光显微镜观察其形态。取20只新西兰大白兔,在动物双侧后肢内侧分别建立4cm×3cm隐动、静脉逆行岛状皮瓣模型(n=10)和顺行岛状皮瓣模型(n=10),血管蒂长3cm。将一侧后肢随机设定为实验组,皮瓣制备后注射已标记的RBC悬液5pL;对侧为对照组,不注射示踪剂。实验组按顺行和逆行皮瓣分成两组,即顺行皮瓣组和逆行皮瓣组,每组10个;再根据注入示踪剂途径不同,分为动脉和静脉2个亚组,每亚组5个皮瓣。注射示踪剂5S后取下皮瓣立即冷冻,取连续的3张冰冻切片(5~7pm),其中2张行HE染色和GENMED染色,另]张不染色直接压片,荧光显微镜观察荧光分布。结果流式细胞仪分析FITC标记的RBC阳性率在99%以上,荧光强度均≥10。;倒置荧光显微镜下标记的RBC呈均匀分布的绿色荧光,荧光强度均匀、稳定。冰冻切片显示实验组皮瓣蒂部均出现荧光,对照组未见荧光。顺行岛状皮瓣组荧光主要分布在静脉腔、静脉壁、动脉内膜和外膜;逆行岛状皮瓣组荧光分布在动脉内膜、外膜和静脉壁。结论荧光示踪剂可用于静脉回流研究,顺行岛状皮瓣静脉主要通过静脉腔、静脉壁、动脉内膜和外膜回流;逆行岛状皮瓣静脉主要通过动脉内膜、外膜和静脉壁的“迷宫式途径”回流。 相似文献
109.
干细胞技术结合新型可降解材料进行腰椎融合的临床研究 总被引:1,自引:0,他引:1
目的 探索富集骨髓干细胞技术进行腰椎融合治疗脊柱疾病的疗效.方法 腰椎退行性疾患患者56例,根据行下腰椎后路融合手术中植骨融合材料的不同,分为富集骨髓干细胞快速复合多孔β-磷酸三钙(13-TCP)复合材料组(复合材料组,n=30)和自体髂骨植骨组(自体骨组,n=26).对复合材料组富集前后骨髓体积、有核细胞(NCs)和碱性磷酸酶染色阳性的细胞集落(CFUs/ALP+)计数,分析富集效率;结合随访、影像学检查和Oswestry功能评分等综合评定疗效.结果 复合材料组术中平均抽取骨髓血(249±31)ml,富集技术平均回收(43±11)ml,NCs由(15.9±3.3)x106/ml浓缩至(44.1±10.8)×106/ml,富集后CFUs/ALP+数量由(118±86)/ml浓缩至(486±305)/ml.临床随访(26.3±7.5)个月.两组中患者的年龄、性别、病种分布及融合节段无显著差异,复合材料组与自体骨组融合率分别为93.3%和96.2%(P>0.05).两组手术时间的差异也无统计学意义(P>0.05).复合材料组术中患者的总出血量高于自体骨组(P<0.01),但术中自体血回输可以将接近1/2的术中出血回输给患者.复合材料组术后骨髓采集部无血肿和慢性疼痛,伤口渗出或局部肿胀4例,均自行愈合;而自体骨组术后髂骨采集部血肿(15.4%)和慢性疼痛(26.9%),无伤口渗出的情况.两组间Oswestry功能评分的差异无统计学意义(P>0.05).结论 富集骨髓干细胞技术可在术中一期应用,提高骨髓MSCs的浓度,安全、快速.富集骨髓干细胞快速复合多孔β-磷酸三钙后,可作为腰椎后外侧融合的植骨替代品. 相似文献
110.
Surgically Managed Gastrointestinal Stromal Tumors: A Comparative and Prognostic Analysis 总被引:3,自引:0,他引:3
Hassan I You YN Shyyan R Dozois EJ Smyrk TC Okuno SH Schleck CD Hodge DO Donohue JH 《Annals of surgical oncology》2008,15(1):52-59
BACKGROUND: Tyrosine kinase inhibitors have been shown to have marked clinical efficacy in patients with unresectable or metastatic gastrointestinal stromal tumors (GIST). We performed a comparative and prognostic analysis of our experience with surgically managed GIST to determine factors associated with adverse oncologic outcomes. METHODS: Oncologic outcomes of 191 patients with primary GIST surgically managed between 1978 and 2004 at a single institution were reviewed. Prognostic factors were analyzed by Cox analysis (hazard ratio [HR] and 95% confidence interval [95% CI]) and included age, sex, disease presentation (asymptomatic vs. symptomatic), tumor site (stomach, small bowel, colorectal), disease extent (localized vs. metastatic) and risk levels (high, intermediate, low, very-low) assigned on the basis of size and number of mitoses according to current National Institutes of Health recommendations. Primary end points were disease-free survival (DFS) and disease-specific survival (DSS). RESULTS: A total of 186 patients (97%) had c-kit-positive GIST. There were 54% high, 22% intermediate, 18% low, and 8% very low risk GIST originating from the stomach (54%), small bowel (36%), and colon and rectum (10%). Median patient age was 65 (range, 13-91) years, and 108 subjects (57%) were male. Seventy-two percent of patients had symptomatic local disease, and 21% patients had synchronous metastases. Most (95%) underwent R0 resections of their primary tumor. Among 146 patients (76%) with localized disease at presentation undergoing R0 resection, the 5-year DFS was 65%. High-risk GIST (HR 12, 95% CI, 5-32, P < .0001), symptomatic presentation (HR 2.5, 95% CI, 1.1-6, P = .04), and GIST in the small bowel (HR 2.8, 95% CI, 1-5, P = .003) were independently associated with decreased DFS. After a median follow-up of 63 months among survivors, the 5-year DSS was 68%. High-risk disease (HR 14.3, 95% CI, 5-41, P < .0001), symptomatic presentation (HR 3.1, 95% CI, 1.2-7.9, P = .02), and GIST in the small bowel (2.6,3 95% CI, 1-5, P = .006) were independently associated with decreased DSS. CONCLUSIONS: High-risk GIST are associated with increased disease recurrence and decreased survival despite complete surgical resection. These patients should receive adjuvant therapy in the form of tyrosine kinase inhibitors. 相似文献