Use of a new elastin patch and glue for repair of a major duodenal injury

Major duodenal injury with significant tissue loss causes high morbidity and mortality. Our new elastin based heterograft combined with small intestinal submucosa (SIS) and biodegradable glue could be used for repair of such defects. Twenty-four domestic pigs were anesthetized and underwent celiotomy. A 2 cm circular defect was created at the second portion of the duodenum with scissors, excising one-half of its circumference. Our elastin patch, combined with SIS, was applied to cover the defect using biodegradable cyanoacrylate glue and a few sutures. It was then covered with omentum. Animals were followed by weight gain, endoscopic evaluation, and upper GI barium studies. After 2-5 months, animals were sacrificed to obtain specimens. One failed in 3 days due to a technical problem, and one failed in 20 days due to an abdominal abscess. The other 22 animals (22/24, 91.7%) did well, gaining weight. Early endoscopic studies (5-14 d) showed an intact patch. Upper GI studies showed varying degrees of stenosis at the repair site at 3-4 months. Sacrifice after 2-5 months showed complete healing of the defect and a dissolved patch. Our new elastin patch material provides a reliable barrier for repair of duodenal injury, and the biodegradable glue provides quick and easy watertight tissue fusion for our patch.     

Chondrocyte-seeded hydroxyapatite for repair of large articular cartilage defects. A pilot study in the goat

The aim of this study was to evaluate the potential for restoration of a large cartilage defect in the goat knee with hydroxyapatite (HA) loaded with chondrocytes. Isolated chondrocytes were suspended in fibrin glue, seeded on top of the HA, and then the composite graft was implanted in the defect. After transplantation, cell behaviour, newly synthesised matrix and the HA–glue interface were assessed histologically after 2, 4, 12, 26 and 52 weeks. Special attention was paid to the incorporation process of HA in the subchondral bone and interactions between this biomaterial and the fibrin-glue–chondrocyte suspension.

Chondrocytes in the glue proved to survive the transplantation procedure and produced new metachromatically stained matrix two weeks after implantation. The glue–cell suspension had penetrated the superficial porous structure of the HA. Four weeks after surgery, islands of hyaline-like cartilage were observed at the HA–glue interface. A layer of fibrous tissue was formed surrounding the HA graft, resulting in a relatively instable fixation of the HA in the defect. This instability of the graft in the defect, possibly together with early weight bearing, resulted in a gradual loss of the newly formed hyaline cartilage-like repair tissue. Progressive resorption of the HA occurred without any sign of active bone remodelling from the host site. One year after surgery part of the defect which extended down to the cancellous bone had been predominantly restored with newly formed lamellar bone. Only small HA remnants were still present at the bottom of the original defect. Resurfacing of the joint had occurred with fibrocartilaginous repair tissue.

The absence of adequate fixation capacity of the HA near the joint space resulted in a relative instability of the graft with progressive resorption. Therefore, HA is not a suitable biomaterial to facilitate the repair of large articular cartilage defects.     

Different outcomes in urethral reconstruction using elastin and collagen patches and conduits in rabbits

OBJECTIVES: To study the feasibility of urethral reconstruction with two urethroplasty techniques using an elastin and collagen heterograft in rabbits. MATERIALS AND METHODS: Fifty-two male rabbits were studied. Two types of injury, (1) a 1.5 x 0.6 cm2 semicircumferential defect; (2) a 1.5 cm segmental defect of the penile urethra, were created and repaired using size-matched elastin and collagen patches or tubed conduits. Urethral repair by primary closure for the type 1 injury and a tubularized autologous bladder mucosal graft for the type 2 injury served as controls. At 3 months, urethral diameter was measured with retrograde urethrography. The animals were then euthanized for histological examination. RESULTS: The postoperative complication rate was significantly higher in the urethral reconstructions using tubed collagen (83%) and elastin (50%) grafts compared to the patch onlay grafts (p = 0.001 for collagen and p = 0.01 for elastin) and tubularized ABM (10%, p = 0.003 and 0.05, respectively). At the type 2 injury site, a dense circumferential fibrosis developed after all repairs. Only minimal ventral fibrosis presented in the type 1 injury repair. The intensity of chronic inflammation and fibrosis was greatest when collagen was used for the urethral repair. In the elastin urethral repairs the urethral diameter decreased significantly for the tubed repair compared to the patch onlay (p = 0.02). CONCLUSION: Urethral injury repair using elastin and collagen biomaterials is feasible in the rabbit model. The results of onlay urethroplasty using the elastin and collagen patches are significantly superior to those using the elastin and collagen tubed conduits.     

Usefulness of the laparoscopic Heller-Dor operation for esophageal achalasia: introducing the procedure to our institution

Our institution introduced laparoscopic surgery for esophageal achalasia in 2001. The present report summarizes 15 cases of achalasia treated with laparoscopic Heller myotomy and anterior fundoplication according to the method of Dor, and we have investigated the therapeutic effects on specific symptoms such as dysphagia, reflux, and chest pain. From February 2001 through January 2007, the laparoscopic Heller-Dor operation was performed in 15 patients, including 7 men and 8 women. Achalasia was classified morphologically on esophagography as spindle type in 11 cases, flask type in 3 cases and sigmoid type in 1 case. The degree of esophageal dilatation was classified as grade I in 8 cases, grade II in 6 cases, and grade III in 1 case. Dysphagia was the main symptom and was present in all cases. The mean disease duration was 4.3 years (range, 5 months to 20 years), and the mean weight loss was 4.2 kg. All patients underwent endoscopic dilatation preoperatively. Intraoperative blood loss ranged from 0 to 100 mL (mean, 21 mL). Adequate Heller myotomy was considered more than 6 cm and more than 3 cm in the esophagus and the stomach, respectively. Injury to the esophageal mucosa occurred during the myotomy in 3 cases but could be repaired in all cases during the laparoscopic procedure. All patients reported an excellent level of satisfaction postoperatively. In conclusion, the laparoscopic Heller-Dor operation for esophageal achalasia is a useful procedure because the postoperative satisfaction level of patients is excellent. Despite the risk of mucosal injury, adequate Heller myotomy should be achieved to obtain a good prognosis. It is, therefore, of utmost importance to obtain mastery over the surgical technique to repair any mucosal injury that might occur.     

Repair of articular cartilage defect by cell transplantation

Full-thickness articular cartilage defects are a major clinical problem; however, at present there is no treatment that is widely accepted to regeneratively repair these lesions. The current therapeutic approach is to drill or abrade the base of the defect to expose the bone marrow with its cells and growth factors. This usually results in a repaired tissue of fibrocartilage that functions poorly in the loaded joint environment. Recently, autologous cultured chondrocyte transplantation and mosaic plasty were explored. We can repair small articular cartilage defects using these methods, although their effectiveness is still controversial. We have reported that transplantation of allogeneic chondrocytes embedded in collagen gels or allogeneic chondrocytes cultured in collagen gels could repair articular cartilage defect in a rabbit model. We also reported that autologous culture-expanded bone marrow mesenchymal cell transplantation could repair articular cartilage defect in a rabbit model. This procedure offers expedient clinical use, given that autologous bone marrow cells are easily obtained and can be culture-expanded. We transplanted autologous culture-expanded bone marrow cells into the cartilage defect of the osteoarthritic knee joint on 11 patients at the time of high tibial osteotomy. As early as 6.8 weeks after transplantation, the defect was covered with white soft tissue, in which slight metachromasia was histologically observed. Thirty-three weeks after transplantation, the repaired tissue had hardened. Histologically, repaired tissues showed stronger metachromasia and a partial hyaline cartilage-like appearance. This procedure may prove a promising method by which to repair articular cartilage defects.     

新型可塑形同种骨修复材料修复运动性关节软骨损伤

BACKGROUND: Currently, the components and preparation methods of plastic bone repair materials remain controversial, and rare studies focus on their repair effects on sport-related articular cartilage injury. OBJECTIVE: To analyze the effect of a novel plastic homogeneous bone repair material to repair sport-related articular cartilage injury. METHODS: Thirty-six New Zealand rabbits were selected to prepare articular cartilage injury models, and were randomized into two groups. Model rabbits were repaired with the novel plastic homogeneous bone material (a composite of demineralized bone matrix and collagen) as experimental group, while the others repaired with sodium hyaluronate gel as control group. At 3 weeks after repair, treadmill system was utilized to stimulate sports training after athlete injury, for five consecutive sessions of 30 minutes each. At 16, 18 and 20 weeks after repair, the defect region was observed histologically. RESULTS AND CONCLUSION: At 16 weeks after repair, the defect region healed well and integrated with the surrounding tissues, and no significant inflammatory reaction appeared around the material in the experimental group; in the control group, a fissure appeared at the defect region but with no inflammatory reaction, and the material integrated with the interstitial site. At 18 weeks after repair, closely arranged acellular bone matrix could be found in the defect region, fibrous connective tissues were fewer, and there was a new bone formation around the edge of host bone in the experimental group; the defect region healed, but new bones were fewer in the control group. At 20 weeks after repair, the defect region in the experimental group was filled with fibrous connective tissues, in which there were numerous new blood vessels, and a few of new tissues appeared around the edge of host bone; the defect region in the control group was improved and no neovascularization occurred. These findings suggest that the novel plastic homogeneous bone material can promote the repair of sport-related articular cartilage injury with less rejection reactions.     

The synergistic effects of microfracture, perforated decalcified cortical bone matrix and adenovirus-bone morphogenetic protein-4 in cartilage defect repair

We reported a technique for articular cartilage repair, consisting of microfracture, a biomaterial scaffold of perforated decalcified cortical bone matrix (DCBM) and adenovirus-bone morphogenetic protein-4 (Ad-BMP4) gene therapy. In the present study, we evaluated its effects on the quality and quantity for induction of articular cartilage regeneration. Full-thickness defects were created in the articular cartilage of the trochlear groove of rabbits. Four groups were assigned: Ad-BMP4/perforated DCBM composite (group I); perforated DCBM alone without Ad-BMP4 (group II); DCBM without perforated (group III) and microfracture alone (group IV). Animals were sacrificed 6, 12 and 24 weeks postoperation. The harvested tissues were analyzed by magnetic resonance image, scanning electron microscope, histological examination and immunohistochemistry. Group I showed vigorous and rapid repair leading to regeneration of hyaline articular cartilage at 6 weeks and to complete repair of articular cartilage and subchondral bone at 12 weeks. Groups II and III completely repaired the defect with hyaline cartilage at 24 weeks, but group II was more rapid than group III in the regeneration of repair tissue. In group IV the defects were concave and filled with fibrous tissue at 24 weeks. These findings demonstrated that this composite biotechnology can rapidly repair large areas of cartilage defect with regeneration of native hyaline articular cartilage.     

Evaluation of early-stage osteochondral defect repair using a biphasic scaffold based on a collagen-glycosaminoglycan biopolymer in a caprine model

The aim of this study was to evaluate a new collagen-GAG-calcium phosphate biphasic scaffold for the repair of surgically created osteochondral defects in goats. Comparison of morphological, histological and mechanical performance of the repair tissue was made with defects repaired using a synthetic polymer scaffold. Defects were created in the medial femoral condyle (MFC) and lateral trochlear sulcus (LTS) of Boer Cross goats and evaluated at 12 and 26 weeks. It was found that the total histology score of the collagen-GAG based biomaterial (23.8; SD 1.7) provided a significant improvement (p<0.05) over the biphasic PLGA material (19;3) and the empty control defect (17.3;1.2) in the LTS. The overall trajectory of histological and morphological improvement between 12 and 26 weeks was found to be higher for the collagen-GAG scaffold compared to the PLGA material. The occurrence of sub-chondral bone cysts was lower for the collagen-GAG scaffold with an incidence of 17% of defects, compared to 67% for the PLGA material at 26 weeks. The cartilage repair tissue for both materials evaluated was superior after 26 weeks implantation than the empty control with 75% of the collagen-GAG-treated defects showing markedly more hyaline-like cartilage and 50% of the PLGA sites exhibiting hyaline-like appearances, compared to 17% for the empty control. These early stage data indicate biphasic scaffolds based on collagen-GAG and PLGA both provide indications of satisfactory development of a structural repair to surgically prepared osteochondral defects. Furthermore, the biomaterial composition of the collagen-GAG may provide a more favourable environment for osteochondral repair.     

The use of keratin biomaterials derived from human hair for the promotion of rapid regeneration of peripheral nerves

The management of trauma-associated nerve defects is difficult because of the absence of autologous donor motor or sensory nerves. Pre-clinical development and clinical experience has shown that damaged nerves can be surgically repaired using a tubular conduit interposed across the defect. Acceptable patient outcomes are achieved so long as the gap distance does not exceed a few centimeters. Although research in animals has demonstrated that nerve repair can be facilitated across slightly larger gaps by introducing a biomaterial filler into the conduit lumen, these biomaterials are not typically "neuroinductive" (i.e. capable of acting directly on regenerative cells to enhance nerve tissue formation beyond clinical limits). Moreover, their use does not often result in functional recovery equivalent to nerve autograft, the clinical gold standard. Here we show that a biomaterial gel made from the proteins found in human hair can mediate a robust nerve regeneration response, in part through activation of Schwann cells. In vitro, keratins extracted from human hair enhance the activity of Schwann cells by a chemotactic mechanism, increase their attachment and proliferation, and up-regulate expression of important genes. Moreover, these characteristics translate to improved functional nerve recovery in an animal model. These results suggest that a biomaterial derived from human hair keratins is neuroinductive and can facilitate an outcome comparable to autograft in a nerve injury model.     

Repair of cranial bone defects with adipose derived stem cells and coral scaffold in a canine model

Adipose derived stem cells (ASCs) with osteogenic differentiation potential have been documented as an alternative cell source for bone regeneration. However, most of previous in vivo studies were carried out on small animals along with relatively short-term follow-up. In this study, we investigated the feasibility of using ASCs and coral scaffolds to repair a cranial bone defect in a canine model, and followed up the outcome for up to 6 month. Autologous ASCs isolated from canine subcutaneous fat were expanded, osteogenically induced, and seeded on coral scaffolds. Bilateral full-thickness defects (20 mm×20 mm) of parietal bone were created. The defects were either repaired with ASC-coral constructs (experimental group) or with coral alone (control group). Three-dimensional CT scan showed that new bones were formed in the experimental group at 12 weeks post-implantation, while coral scaffolds were partially degraded in the control group. By radiographic analysis at 24 weeks post-transplantation, it was shown that an average of 84.19±6.45% of each defect volume had been repaired in experimental side, while the control side had only 25.04±18.82% of its volume filled. Histological examination revealed that the defect was repaired by typical bone tissue in experimental side, while only minimal bone formation with fibrous connection was observed in the control group. The successful repair of critical-sized bone defects via the current approach substantiates the potentiality of using ASCs with coral scaffolds for bone regeneration.     

Low-level laser therapy, at 60 J/cm2 associated with a Biosilicate(®) increase in bone deposition and indentation biomechanical properties of callus in osteopenic rats

We investigate the effects of a novel bioactive material (Biosilicate(?)) and low-level laser therapy (LLLT), at 60 J/cm(2), on bone-fracture consolidation in osteoporotic rats. Forty female Wistar rats are submitted to the ovariectomy, to induce osteopenia. Eight weeks after the ovariectomy, the animals are randomly divided into four groups, with 10 animals each: bone defect control group; bone defect filled with Biosilicate group; bone defect irradiated with laser at 60 J/cm(2) group; bone defect filled with Biosilicate and irradiated with LLLT, at 60 J/cm(2) group. Laser irradiation is initiated immediately after surgery and performed every 48 h for 14 days. Histopathological analysis points out that bone defects are predominantly filled with the biomaterial in specimens treated with Biosilicate. In the 60-J/cm(2) laser plus Biosilicate group, the biomaterial fills all bone defects, which also contained woven bone and granulation tissue. Also, the biomechanical properties are increased in the animals treated with Biosilicate associated to lasertherapy. Our results indicate that laser therapy improves bone repair process in contact with Biosilicate as a result of increasing bone formation as well as indentation biomechanical properties.     

小腿内侧皮瓣在前臂皮肤血管缺损中的应用

目的应用小腿内侧游离皮瓣并血管、神经串联移植修复伴有血管、神经缺损的前臂毁损伤，观察其临床应用效果。方法2000年-2007年治疗前臂毁损伤患者12例，均有肢体远端大面积皮肤软组织以及血管、神经缺损，设计小腿内侧游离皮瓣并血管、神经串联移植，皮瓣最大面积25cm×17cm，一期修复组织缺损。结果12例皮瓣及远端肢体全部成活，术后随访7个月至2年，修复的前臂均成活，功能恢复满意。结论对于大面积皮肤缺损而且伴有重要血管、神经缺损的前臂严重毁损伤，应用小腿内侧游离皮瓣并血管、神经串联移植方法修复，临床效果满意，既解决了创面的组织缺损又恢复肢体血运。     

丝素蛋白复合骨髓间充质干细胞构建组织工程化骨修复节段性骨缺损的实验研究

目的 探讨丝素蛋白材料复合骨髓间充质干细胞构建组织工程化骨组织修复兔桡骨的节段性骨缺损的可行性.方法 分离培养兔骨髓间充质干细胞,与丝素蛋白膜材料复合培养,扫描电镜观察细胞在材料上的生长情况.将24只新西兰大白兔制成桡骨中段1.5cm长的骨缺损模型,随机分为3组:实验组(植入细胞材料复合物)、对照组(单纯植入丝素蛋白材料)、空白组(不植入修复材料).术后2,4,8,12周分别行大体观察、组织学观察和X线观察,比较3组骨缺损修复的情况.结果 骨髓间充质干细胞在丝素蛋白膜材料上生长情况良好.术后2,4,8,12周放射学检查新骨生成以及组织学检查新骨生成情况,实验组均优于对照组,空白组各时点均无新骨形成.结论 丝素蛋白材料与骨髓间充质干细胞体外复合培养构建的组织工程化骨能够修复兔桡骨缺损,可以作为组织工程骨的支架材料的全新来源. Abstract： Objective To investigate the possibility of adopting the silk fibroin biomaterial as the scaf-fold for bone marrow mesechymal stem cells(BMSCs) in the repair of rabbit radial defects. Methods BMSCs were isolated and co-cultured with the silk fibroin biomaterial in vitro. The growth condition of these cells on the scaffold was observed under electronic microscope. Bone defect models were made by removing 15 mm length of midshaft radial bone in 24 New Zealand rabbits. Animals were randomly devided into the experimental group in which the BMSCs seeded silk fibroin scaffold were transplanted, control group in which simple silk fibroin bioma-terial scaffold was adopted and blank group in which rabbits were left untreated. The repair of the defects was observed at 2, 4, 8, 12 weeks after operation, respectively. Results The rabbits BMSCs grew well on the material and the animals treated with grafts exhibited new bone formation. Result from experimental group was apparently superior to that of the control group at 2, 4, 8, 12 we     

组织工程骨修复兔桡骨节段性缺损血液流变性及局部血流量的变化

目的 观察组织工程骨修复骨缺损过程中，实验动物血液流变性和骨缺损修复区血流量的变化。方法 选择30只新西兰白兔，制作15mm长的桡骨节段性骨缺损模型，根据植入不同移植材料分为实验组和对照组，实验组于动物左侧桡骨缺损区植入组织工程骨，对照组植入部分脱蛋白骨，观察各组动物术后1h、7h、14d血液流变性和术后14d骨缺损修复区血流量的变化。结果 实验组与对照组比较，血液流变学指标和骨缺损修复区血流量差异显著。组织工程骨修复骨缺损，实验动物全身血液黏度降低，骨缺损修复区局部血流量增加。结论 与单纯材料比较，组织工程骨可促进血液流变学及局部血流量的改善。     

牛心包补片修复心脏间隔缺损的应用

背景：心脏涤纶补片因其质地薄、质量轻、生物相容性好等优点常规用于心脏手术,但最近几年发现,用心脏涤纶补片对心室间隔缺损修补后,一旦发生术后残余漏,较易引起溶血、细菌或真菌感染。 目的：探讨应用牛心包补片修复心脏间隔缺损的疗效。 方法：采用戊二醛固定的牛心包补片修补152例心脏间隔缺损患者,其中房间隔缺损56例,室间隔缺损78例,部分房室间隔缺损18例。术后复查心电图、胸片、心脏超声,观察其术后早期病情、血流动力学和心脏功能。 结果与结论：152例患者均完成修补手术,术后无早期死亡,患者随访2-6个月,牛心包补片在使用过程中及术后早期均未发现漏血、溶血、血栓、感染、排斥反应等并发症。1例患者因合并肺动脉高压,术后第1天出现高血压危象,经过抢救后好转。复查心电图、胸片、心脏超声可见心脏间隔缺损修补完全,无残余分流;肺动脉压力明显下降;活瓣已关闭无分流;心脏功能正常。证实牛心包补片可以有效修复心脏间隔缺损,改善患者的血流动力学和心功能,近期效果满意,是一种良好的心脏间隔缺损修补材料。     

In vivo degradation of 14C-labeled small intestinal submucosa (SIS) when used for urinary bladder repair

The rate of in vivo degradation was determined for a naturally occurring biomaterial derived from the extracellular matrix of the small intestinal submucosa (SIS). The SIS was labeled by giving weekly intravenous injections of 10 microCi of 14C-proline to piglets from 3 weeks of age until the time of sacrifice at 26 weeks. The resultant SIS prepared from these pigs contained approximately 10(3) fold more 14C than unlabeled tissues. The labeled SIS was used to repair experimental defects in the urinary bladder of 10 dogs. The animals were sacrificed at post-operative times ranging from 3 days to 1 year and the remodeled urinary bladder tissue was harvested for evaluation of 14C by a combination of liquid scintillation counting and accelerator mass spectrometry. The remodeled tissue contained less than 10% of the 14C (disintegrations per minute/gram tissue wet weight) at 3 months post-surgery compared to the SIS biomaterial that was originally implanted. The SIS scaffold was replaced by host tissue that resembled normal bladder both in structure and function. After implantation, 14C was detected in highest concentrations in the blood and the urine. The SIS bioscaffold provides a temporary scaffold for tissue remodeling with rapid host tissue remodeling, degradation, and elimination via the urine when used as a urinary bladder repair device.     

Localization of Carboxy-terminal Type II Procollagen Peptide (pCOL-II-C) and Type II Collagen in the Repair Tissue of Full-thickness Articular Cartilage Defect

It is well established that a full-thickness articular cartilage defect is repaired with a fibrocartilaginous tissue of which cells are derived from undifferentiated mesenchymal stem cells in the bone marrow. To characterize the repair tissue immunohistochemically, full-thickness defects were created in rabbit knee joints, and the repair tissues immunostained at 3, 6, and 12 weeks after surgery. Well characterized polyclonal antibody against carboxy-terminal type II procollagen peptide (pCOL-II-C) and monoclonal antibody against type II collagen were used to evaluate the repair tissue with regard to the metabolism of type II collagen. lmmunohistochemistry revealed that pCOL-II-C was localized in or around most of the repair cells obtained at 3 and 6 weeks after surgery, while type II collagen distributed mainly in the pericellular matrix of metaplastic round-shaped repair cells. The results suggest that the repair cells taken at the early stage of the repair process of the defect could originally have more activity of type II collagen synthesis.     

快速成型聚乳酸-聚羟乙酸/磷酸三钙支架修复兔桡骨缺损

背景：理想的骨修复材料除必须具有生物相容性、可吸收性、利于血管化及迅速被新生组织替代的孔隙率,还需要有与骨组织相似三维结构。 目的：检验快速成型工艺制作的聚乳酸-聚羟乙酸/磷酸三钙支架复合骨形态发生蛋白修复兔桡骨缺损的效果。 方法：将乳酸乙醇酸共聚物溶于1,4-二氧六环中并混合粉末状磷酸三钙制备成液态的浆料,放入生物材料快速成形机TissFormTM制备出直径5 mm,长15 mm的圆柱形人工骨载体材料。按每个材料15 mg的标准,采用预湿、负压复合骨形态发生蛋白、冻干3步处理,制备出活性人工骨材料。健康新西兰大白兔20只,制备右前肢桡骨中上段15 mm骨缺损模型,实验组和对照组分别植入复合骨形态发生蛋白的活性人工骨和未复合骨形态发生蛋白的单纯支架。通过影像学、组织学、材料降解及骨密度评价修复兔桡骨缺损的效果。 结果与结论：12周时实验组骨缺损愈合,新生骨痂连接缺损断端并塑形,支架材料近于完全降解,各检测指标与对照组比较差异均有显著性意义,对照组骨缺损内未见新骨形成。结果表明复合骨形态发生蛋白的聚乳酸-聚羟乙酸/磷酸三钙支架可以很好的修复兔15 mm骨缺损,且降解速度与成骨速度匹配良好。     

多孔丝素蛋白/羟基磷灰石复合脂肪间充质干细胞修复兔关节软骨及软骨下骨缺损

背景：丝素蛋白/羟基磷灰石是细胞立体培养的良好支架,是临床常用的骨缺损修复材料,具有良好的生物相容性。脂肪干细胞具有向骨及软骨细胞分化的潜能,适合骨软骨缺损修复。 目的：观察转化生长因子β1和胰岛素样生长因子1联合成软骨诱导脂肪干细胞与丝素蛋白/羟基磷灰石复合后修复兔关节软骨及软骨下骨缺损的效果。 方法：取新西兰大白兔56只,2只用于传代培养脂肪间充质干细胞,以3×109 L-1浓度接种到丝素蛋白/羟基磷灰石。其余54只新西兰大白兔,在股骨髁间制备软骨缺损模型,随机分为细胞复合材料组、单纯材料组和空白对照组,细胞复合材料组植入复合脂肪间充质干细胞的丝素蛋白/羟基磷灰石;单纯材料组植入丝素蛋白/羟基磷灰石;空白对照组不作任何植入。从大体、影像学、组织学观察比较缺损的修复情况。 结果与结论：12周时大体观察、CT、磁共振和组织学检查细胞材料复合组软骨及软骨下骨缺损区完全被软骨组织修复,修复组织与周围软骨色泽相近,支架材料基本吸收,未见明显退变和白细胞浸润,所有标本均未见丝素蛋白残留。单纯材料组缺损区缩小、部分修复,且呈纤维软骨样修复。空白对照组缺损无明显修复。提示复合脂肪间充质干细胞的丝素蛋白/羟基磷灰石修复兔关节软骨及软骨下骨缺损能力优于单纯丝素蛋白/羟基磷灰石材料。丝素蛋白/羟基磷灰石复合脂肪间充质干细胞可形成透明软骨修复动物膝关节全层软骨缺损,重建关节的解剖结构和功能,可作为新型骨软骨组织工程支架。     

镁锶合金修复兔桡骨骨缺损的实验研究

目的研究Mg-Sr合金对兔桡骨骨缺损的修复效果。方法将30只新西兰大耳白兔随机分为Mg-Sr合金组和空白对照组两组,每组15只。手术制备双侧桡骨中段1.0cm骨缺损模型,镁锶合金组缺损部位植入Mg-Sr合金;空白对照组不植入任何材料作为对照。两组分别于术后4、8和12周各处死5只动物取材,行X线片、组织学检查及Micro-CT,观察各组对骨缺损的修复效果。结果 Mg-Sr合金组骨缺损得到了修复,空白对照组仅有少量新骨形成,但骨缺损未得到修复。结论 Mg-Sr合金对兔桡骨骨缺损有很好的修复效果。