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81.
82.
ObjectiveThe current study investigated the role of CircCDR1as on angiogenesis of bone microvascular endothelial cells (BMECs) isolated from non‐traumatic ONFH.MethodsForty corticosteroid‐induced ONFH patients received THA were enrolled in our study. Expressions of CircCDR1as, miR‐135b, and FIH‐1 were detected by qRT‐PCR in affected necrosis tissue and non‐affected normal tissue. Bone microvascular endothelial cells (BMEC) were isolated from six patients and treated with 0.1 mg/mL hydrocortisone to establish a GC‐damaged model of BMECs. Circ CDR1as plasmid and miR‐135b mimic were transfected into BMECs. BMEC proliferation was assessed using MTT assays. The migration ability of cells was detected by scratch‐wound assays. Matrigel assay was performed to detect angiogenesis in vitro. Western blot assay was used to detect HIF‐1α, VEGF, and FIH‐1 expressions. FISH, RNA pull down, RIP, and luciferase assay were carried out to determine the interaction of CircCDR1as, miR‐135b, and FIH‐1.ResultsCircCDR1as was upregulated(2.02 ± 0.30 vs. 1.00 ± 0.10,P < 0.001) whereas miR‐135b was downregulated (0.55 ± 0.12 vs. 1.00 ± 0.10,P < 0.001) in affected tissues than in non‐affected tissues. Expression of CircCDR1as and FIH‐1 were negatively associated with miR‐135b in affected tissues (CircCDR1as with miR‐135b: r = −0.506, P < 0.001; FIH‐1 with miR‐135b r = −0.510, P < 0.001). Total blood tubule density was increased when CircCDR1as was silenced compared with NC (P < 0.01 vs. NC). The number of migrated BMECs were significantly increased in CircCDR1as silencing group compared with NC group (P < 0.05 vs. NC). In addition, CircCDR1as plasmids transfection increased the protein expressions of FIH‐1 (P < 0.05 vs. NC) and reduced the HIF‐1α as well as VEGF expression compared with NC group (P < 0.05 vs. NC). FISH, RNA pull down, RIP, and luciferase assay identified that FIH‐1 was a target of miR‐135b and could be modulated by CircCDR1as.ConclusionCircCDR1as decreases angiogenesis and proliferation of BMECs by sponging miR‐135b and upregulate FIH‐1.  相似文献   
83.
PurposeLate-diagnosed dislocated hips underwent open reduction, Dega osteotomy, and proximal femoral osteotomy between 1968 and 1988. The objectives of this study are to assess the survival of hips into adulthood, clinical and radiological outcome, patients’ life perspectives and the risk factors of failure.MethodsAn assessment of 67 hips treated when younger than five years (<age 5yr. group) and 71 hips in the group aged older than five years (+age 5yr.) was performed. All cases were evaluated clinically and radiographically, and survival was assessed, considering hip replacement as endpoints for failure (abbreviation HR+ refers to hips that underwent hip replacement surgery; HR- refers to hips that have not been replaced at the follow-up). The fertility rate and the social security disability benefits (SSDB) recipiency percentage were calculated.ResultsThe 40-year survival rates were 73% (95% confidence (CI) 71% to 76%) in the <age 5yr. group, 54% (95% CI 51% to 57%) in the +age 5yr. group, 70% (95% CI 67% to 73%) in one-sided dislocations and 57% (95% CI 54% to 60%) in bilateral dislocations. At follow-up, the median Harris hip and Western Ontario and McMaster Universities Osteoarthritis scores were 90.0 and 13.0 (<age 5yr. group, HR-), 74.0 and 28.0 (+age 5yr. group, HR-), 90.0 and 16.0 (<age 5yr. group, HR+) and 84.5 and 11.5 (+age 5yr. group, HR+), respectively. The operation normalized the radiological parameters. The correlation between the grade of femoral head avascular necrosis (AVN) at a median 2.6 years after the operation and the grade of osteoarthritis at follow-up was 0.38 (p < 0.001). The fertility rate was 1.54. In total, 16.0% (aged under five years) and 38.5% (aged over five years) of patients were receiving SSDB (p = 0.003).ConclusionEarly failure risk factors are older age at the surgical procedure, high AVN grade and bilateral hip involvement. Still, the results facilitate hip reposition whenever technically manageable, even in teenagers.Level of evidenceIII  相似文献   
84.
BackgroudOutcomes of traditional treatment for osteonecrosis of the femoral head (ONFH) are not always satisfactory. Hence, cell-supplementation therapy has been attempted to facilitate necrotic-tissue regeneration. Adipose-derived mesenchymal stem cell (ADMSC) transplantation is potentially advantageous over bone marrow-derived MSC implantation, but its outcomes for ONFH remain unclear. The aim of this study was to determine 2-year radiological and clinical outcomes of culture-expanded autologous ADMSC implantation for ONFH.MethodsEighteen hips with necrotic lesions involving ≥ 30% of the femoral head were included. ADMSCs were harvested by liposuction and culture expanded for 3 passages over 3 weeks. With a 6-mm single drilling, ADMSCs were implanted into the necrotic zone. All patients underwent magnetic resonance imaging (MRI), single-photon emission computed tomography/computed tomography (SPECT/CT) at screening and 6 months, 12 months, and 24 months postoperatively. The primary outcome was the change in the size of necrotic area on MRI. Secondary outcomes were changes in clinical scores and radioisotope uptake on SPECT/CT. Conversion total hip arthroplasty (THA) was defined as the endpoint.ResultsPreoperatively, the necrotic lesion extent was 63.0% (38.4%–96.7%) of the femoral head. The mean Harris hip score was 89.2, the University of California at Los Angeles (UCLA) score was 5.6, and Western Ontario and McMaster Universities Arthritis index (WOMAC) was 79.4. Three patients underwent THA and 1 patient died in an accident. Finally, 11 patients (14 hips) were available for ≥ 2-year follow-up. At the last follow-up, no surgery-related complications occurred, and 14 of 17 hips (82%) were able to perform daily activities without THA requirement. There was no significant decrease in lesion size between any 2 intervals on MRI. However, widening of high signal intensity bands on T2-weighted images inside the necrotic lesion was observed in 9 of 14 hips (64%); 11 of 14 hips (79%) showed increased vascularity on SPECT/CT at 2 years postoperatively. No significant differences were observed between preoperative and 24-month mean Harris hip score (89.2 vs. 88.6), WOMAC (79.4 vs. 75.7), and UCLA score (5.6 vs. 6.2).ConclusionsOur outcomes suggest that culture-expanded ADMSC implantation is a viable option for ONFH treatment without adverse events.  相似文献   
85.
对 50例成人下肢标本的旋股内侧动脉深支和旋股外侧动脉升支的起源、起点、外径、走行、分布以及经这二支血管介入有关的结构进行观测 ,为介入治疗股骨头缺血性坏死提供更接近病变部位及可进行插管的血管。结果表明 ,旋股外侧动脉升支与横支共干起自旋股外侧动脉者占 68% ,升支单独起自旋股外侧动脉占 2 6 % ;旋股内侧动脉深支由旋股内侧动脉主干延续而来。旋股内、外侧动脉深支或升支起点外径分别为 3 0± 0 8mm、 2 8± 0 7mm。从股动脉的起点 ,经股深动脉、旋股外侧动脉至其升支长度为 7 1± 1 1cm ;经股深动脉、旋股内侧动脉至其深支长度为 5 6± 1 4cm。旋股内侧动脉与其深支间约呈 90 。 角 ;旋股外侧动脉与其升支间约呈 1 33。 角。旋股内、外侧动脉深支 (升支 )为营养股骨头和颈的血管 ,这二支血管符合导管插入要求  相似文献   
86.
目的 建立并评价小鼠股骨骨折合并坐骨神经损伤的标准化动物模型。方法 将96只C57BL/6J小鼠随机分为2组,分别为A组:股骨骨折合并坐骨神经损伤组(48只)、B组:股骨骨折组(48只)。A组通过止血钳钳夹致小鼠左侧坐骨神经损伤,于同侧进行股骨开放性骨折联合髓内钢针固定,建立了小鼠股骨骨折合并坐骨神经损伤的模型;B组行左侧股骨开放性骨折联合髓内钢针固定,仅游离坐骨神经,不做钳夹处理。术后仔细观察小鼠行为学变化。于术后第3、5、7、10、14、18天6个时间点,取A组(36只)与B组(36只)左侧坐骨神经,其中每个时间点每组6只,分别通过免疫组化染色来分析坐骨神经损伤修复过程。同时,于第7、14、21和28天4个时间点取小鼠左侧股骨,分别通过股骨X线、Micro-CT、组织学染色来分析并评估在周围神经损伤条件下骨折愈合情况。结果 本实验建立的小鼠股骨骨折合并坐骨神经损伤模型,于建模后第14天小鼠步态基本恢复正常;于第14天坐骨神经纤维结构连续性基本恢复;第7天骨折断端几乎不存在骨痂;至第14天出现少量软骨痂,主要为未分化的间充质干细胞构成;第21天软骨痂开始钙化,骨痂中存在部分肥大的软骨细胞;第28天骨折断端新生骨形成,含有大量肥大的软骨细胞、成骨细胞与骨细胞。结论 通过本研究方法建立的小鼠股骨骨折合并坐骨神经损伤模型愈合过程良好,并较单纯股骨骨折的愈合过程有所迟缓,可很大程度上模拟临床骨折合并周围神经损伤后修复及愈合过程,为合并周围神经损伤的骨折愈合相关研究提供实验基础。  相似文献   
87.
Femoralfracturesinthepresenceofotherintramedullaryimplantsareuncommon Thesefracturesaredifficulttomanageandthepresenceofotherintramedullaryimplantscreatesacomplexproblem Therateofthesefractureshasincreasedduetoanincreaseinthenumberofpatientshavingtota…  相似文献   
88.
两种不同方法治疗股骨头缺血坏死的实验研究   总被引:1,自引:0,他引:1  
目的 观察股骨头坏死的病理变化。观察带血运骨瓣移植术与带血运骨瓣与骨膜生发层细胞复合移植术的疗效。比较两种治疗方法之间是否有差别。探讨血供重建与骨重建相结合的可能性。方法 22只哈白兔分为3组。均将股骨头截下后埋于胸部皮下,制成股骨头坏死模型。3周后,A组对照组6只,无处置;B组8只,将带血运肋骨瓣植入已坏死的股骨头内,C组8只,将带血运肋骨瓣与骨膜生发层细胞复合植入已坏死的股骨头内,12周后,光镜、透射电镜观察股骨头的软骨及骨小梁的结构。结果 A组出现典型骨坏死而无修复,B组出现成骨细胞及红细胞,修复反应出现,C组出现修复反应,且修复效果优于B组。结论 应用哈白兔将股骨头截古后埋藏于皮下,可以制作出 血运肋骨诱发了骨重建,从而加快坏死骨修复,实验性血供重建与骨重建复合移植组对骨坏死的修复优于单纯血供重建组。  相似文献   
89.
探讨股骨头钻孔管移植髋关节外支撑治疗股骨头无菌坏死的疗效。方法 :股骨头钻孔去除坏死骨加上腓骨骨移植 ,髋关节外支撑架固定。结果 :治疗成人股骨头坏死1 1例 ,男 8例 ,女 3例 ;平均年龄 40岁 ,平均病史 2年 ;本组Ⅰ~Ⅲ期 8例 ,Ⅲ~Ⅳ期 3例 ;随访2年 ,优良率 86 6 %。结论 :本术式优点是 :注重彻底清除坏死骨 ,髋关节外植骨 ,早期负重。  相似文献   
90.
目的 探讨老年股骨骨折病人手术前后的护理。方法 采取整体护理与康复指导等措施。结果 通过对 83例老年股骨骨折手术病人的整体化护理 ,使病人的肢体功能恢复情况及病人的满意度有了明显改善和提高 ,与以前的责任制护理相比有显著差异性 (P <0 .0 1)。结论 对病人采用整体护理 ,使老年股骨骨折病人早日康复。  相似文献   
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