同种异体软骨细胞移植修复兔膝关节软骨缺损的免疫反应

目的：探讨同种异体软骨细胞移植修复关节软骨缺损的免疫学变化。方法：将兔分成软骨细胞移植组及骨基质明胶移植组，用免疫学及组织学方法，研究其免疫反应。结果：软骨细胞移植组术后检到淋巴细胞增殖，植入物局部见到淋巴细胞浸润。结论：同种异体软骨细胞移植存在免疫反应。     

同种异体关节移植的手术配合

对13例患者行同种异体关节移植手术。结果均顺利完成手术，未发生术中、术后并发症。提出重视患者的心理护理。充分的术前准备，正确熟练的手术配合及术中护理是顺利手术的重要环节。     

同种异体关节移植的手术配合

对13例患者行同种异体关节移植手术.结果 均顺利完成手术,未发生术中、术后并发症.提出重视患者的心理护理,充分的术前准备,正确熟练的手术配合及术中护理是顺利手术的重要环节.     

吻合血管的同种异体骨、关节移植

吻合血管的同种异体骨体骨关节移植在治疗大段骨关节缺损有着较大的应用前景,也是目前修复重建外科、骨移植领域的研究重点。本就吻合血管的同种异体骨关节移植的抗原性、排斥反应、免疫抑制剂的作用,冷冻的影响等方面研究现状作一综述。     

同种异体半关节移植治疗股骨远端肿瘤

目的 对大段异体骨移植用于骨肿瘤保肢治疗及其相关问题进行分析讨论。方法采用大段异体骨修复骨肿瘤瘤段切除后骨缺损5例，术后X线及同位素骨扫描评定骨愈合，并评估其功能恢复情况。结果手术后3—6个月在X线片显示牢固的生物固定（坚强的外骨痂或已骨性连接）、^99mTc—MDP骨扫描图像显示异体骨早期代谢活跃，2年后逐渐恢复正常。结论 同种异体骨半关节移植治疗股骨远端肿瘤术后观察移植骨与自体骨愈合，关节功能重建方面到达良好表现。     

大段同种异体半关节移植远期疗效分析

目的：探讨分析同种异体半关节移植的临床应用及远期疗效。方法：回顾分析应用同种异体半关节移植治疗近关节骨肿瘤切除后遗留大块骨缺损，就随访资料完整，且随访时间超过5年的70例进行临床分析，异体骨移植长度8－25cm。普通髓内固定25例，交锁髓内钉固定21例，螺栓固定22例，钢板固定2例。结果：70例患者得到随访，平均随访时间10．5年（5－22年）。异体骨愈合68例，不愈合2例。主要并发症，肿瘤避部复发8例，感染7例，骨折3例，关节面塌陷6例，关节强直2例。关节功能按Mankin标准评定，优23例，良19例，中12例，满意率78．2％，结论：同种异体半关节移植是修复骨肿瘤切除后骨缺损的有效手段，但应严格掌握其适应证。     

术后早期活动对同种异体关节移植后关节软骨保护作用的实验研究

目的采用同种异体关节移植动物模型,于术后采用不同处理方法进行对照实验,探讨同种异体关节移植后早期活动对关节软骨的保护作用。方法选用生长条件相同的6月龄新西兰大耳白兔10只(雌雄不限,体重2.5～3.0 kg)作为供体,取其一侧半膝关节,经深低温冻存处理后移植于取下股骨侧半膝关节的6月龄青紫蓝兔(雌雄不限,体重2.5～3.0 kg)膝关节处,术后分别给予早期活动(术后2周,早期活动组,n=5)或持续石膏固定6周(持续固定组,n=5);并取供体对侧半膝关节设立空白对照组(未经任何处理,n=5)和冻存对照组(经深低温处理2周,n=5)。术后分别行大体、X线片及组织学观测,观察同种异体关节软骨的变化情况。结果大体观察示,早期活动组实验兔关节活动良好;持续固定组实验兔关节活动受限明显。X线片示,术后当天、术后2周同种异体关节供体骨端与受体骨端对合整齐、对位对线良好;术后6周,早期活动组3只实验兔受体和供体骨端略有成角畸形,持续固定组对位及对线仍良好。HE染色示,早期活动组同种异体半膝关节标本软骨细胞数量和形态基本正常,偶见核碎裂及核溶解;持续固定组同种异体半膝关节标本中软骨细胞大量减少,大部分细胞核溶解消失,软骨基质中大量纤维组织增生。细胞存活率检测示,早期活动组细胞存活率(49.66%±2.15%)显著高于持续固定组(20.68%±1.24%),比较差异有统计学意义(P<0.05)。扫描电镜观察示,早期活动组同种异体半膝关节标本可见软骨细胞细胞核核膜尚完整,染色质凝聚、边集,线粒体及粗面内质网肿胀;持续固定组同种异体半膝关节标本可见软骨细胞细胞膜消失,软骨细胞与周围基质界限不清,核膜破裂,染色质及细胞质内细胞器消失。结论同种异体关节移植术后进行早期功能活动对兔关节软骨有保护作用,但不能完全阻止软骨退变。     

异体软骨细胞移植修复关节软骨缺损免疫反应及处理

采用异体软骨细胞移植修复关节软骨缺损是当今研究热点。该文综述了异体软骨细胞移植产生免疫反应的原因及解决的方法。     

6例膝同种异体半关节移植的手术配合

自2003年12月-2005年6月，我们共配合实施了6例同种异体膝半关节移植手术，手术过程配合良好，无1例感染。近期效果满意。     

同种异体软骨移植修复关节软骨缺损实验研究

目的 采用兔膝关节软骨标本经打孔梯度降温冻存后行同种异体移植,研究打孔梯度降温冻存对兔关节软骨的影响及其修复关节软骨缺损的效果.方法 自16只2月龄新西兰白兔膝关节股骨髌面取分别取3块骨软骨移植物,随机分为3组.Ⅰ组为实验组,在软骨上以3 mm×3 mm矩阵打孔,Ⅱ、Ⅲ组为对照组,不打孔.分别将软骨标本置于二甲基亚砜冷冻保护溶液中,并经梯度降温至-80℃(Ⅰ、Ⅱ组)或直接置于-80℃(Ⅲ组)保存1周,复温后移植到成年兔相应膝关节部位.术后分批处死动物,通过对移植物的大体形态学、组织学、免疫组化染色光镜观察,研究各组移植物保存效果的差异.结果 Ⅰ、Ⅱ组光镜观察结果明显优于Ⅲ组;Ⅰ组与Ⅱ组结果差异不明显,但Ⅰ组对中间层软骨组织的保护明显加强.结论 关节软骨的梯度降温冷冻保存效果明显优于快速降温冷冻保存,且关节软骨打孔冷冻保存对深层软骨细胞有一定的保护作用,可提高软骨细胞存活率,延缓移植软骨组织的退变过程.     

自体软骨移植的实验研究

目的　探索能促进自体移植软骨生长的新途径。方法　将兔耳软骨切割成大小为１．５ｍｍ×１．５ｍｍ的耳软骨片，均匀地涂布在具有三维空间结构的聚乳酸泡沫支架上，然后将此复合物埋植于兔背皮下，分别于移植后３、６个月取出标本，行大体观察及显微镜下检查。结果　３，６个月后所有植入块均有不同程度的软骨形成，软骨边缘可见有新生软骨，软骨细胞增生活跃，以６个月的软骨量较多。结论　软骨在聚乳酸泡沫上具有生长潜能。     

自体腹膜管替代动脉的研究

作者用１４条犬的带（腹直肌后）鞘腹膜缝制成５ｃｍ～８．５ｃｍ长的腹膜管，间置于切断的腹主动脉。并通过移植前后血液流变学检查，动脉和腹膜管测压，血管造影及形态组织学检查，对腹膜管替代动脉血管的可行性进行研究。结果表明：自体腹膜可作为一种新型的血管替代材料用于动脉重建，特别在缺乏其它血管替代物的紧急情况下，更有其实用价值。     

β-TCP-透明质酸复合支架结合自体MSCs和rhBMP2修复兔关节软骨缺损的实验研究

目的探讨β-磷酸三钙（β—TCP）-透明质酸复合支架结合兔自体间充质干细胞（MSCs）和骨形态发生蛋白-2（rhBMP2）修复兔关节软骨缺损的实验效果。方法24只新西兰兔随机分为4组，于股骨髁关节面制备关节软骨缺损模型（每孔直径4mm，深度6mm）。实验组、对照组Ⅱ及对照组Ⅰ于关节缺损处分别植入β—TCP-透明质酸／MSCs/rhBMP2、β—TCP／MSCs／rhBMP2和β—TCP／MSCs不同组成的工程软骨，空白组不作处理。于术后12周对修复组织行大体、组织学及免疫组化观察。结果实验组能形成丰富的透明软骨样修复组织，与周围组织整合良好；对照组Ⅱ以不成熟透明软骨及纤维软骨为主，与周围组织分界略模糊；对照组Ⅰ以纤维软骨修复为主，与周围组织分界清；空白组无修复组织。Wakitani评分各组间差异均有统计学意义（P〈0．01），实验组明显优于其他组。结论应用β-TCP-透明质酸复合支架结合自体MSCs和rhBMR构建组织工程软骨，是一种较理想的修复关节软骨缺损的方法之一。     

The use of a non-ionic surfactant (P188) to save chondrocytes from necrosis following impact loading of chondral explants.

While current injury criteria for the automotive industry are based on bone fracture, the majority of knee injuries suffered in collisions each year do not involve fracture of bone. Instead, clinical studies of traumatic joint injury often document early pain and development of chronic diseases, such as osteoarthritis. Previous studies suggest chronic disease can be initiated by cell death that occurs in articular cartilage during mechanical trauma to the joint. In the current investigation early necrosis of chondrocytes was investigated after blunt trauma to chondral explants. A non-ionic surfactant (P188) was explored as a potential tool for early intervention into the disease process, as this surfactant has been shown to repair damaged membranes in other cell lines. Three groups of adult bovine chondral explants were equilibrated for 48 h in culture media. Two groups were then loaded to 25 MPa in unconfined compression. Half the specimens in each group were incubated in media supplemented with 8 mg/ml P188 immediately after loading, while the other half was returned to standard media. At 1 and 24 h the percentages of live and dead cells in compressed and control groups were determined with a cell viability stain. At 1 h post-trauma, P188 incubated specimens had a significantly increased percentage of live cells in the superficial zone versus the no-P188 group. At 24 h the percentages of live cells in all three zones of the P188-treated explants were significantly greater than in the no treatment group. This study showed that P188 surfactant could help restore the integrity of cell membranes in cartilage damaged by blunt mechanical trauma. With the ability of P188 to "save" chondrocytes from early necrotic death using in vitro chondral explants, its role in prevention of a post-traumatic osteoarthritis in a diarthrodial joint should be further explored using in vivo animal models.     

WO-1生物衍生骨支架与成骨细胞相容性的实验研究

目的 研究WO-1生物衍生骨复合材料与兔成骨细胞的相容性及体外附着规律，为进一步的体内试验提供基础研究。方法 应用同种异体骨、Ⅰ型胶原及WO-1制备WO-1生物衍生骨复合材料；取幼兔的颅顶骨成骨细胞，经培养液体外培养、扩增后，与WO-1生物衍生骨材料联合培养。通过扫描电镜和倒置相差显微镜观察WO-1生物衍生骨复合材料的形貌特征、细胞与材料的粘附和增殖情况。结果 WO-1生物衍生骨复合材料具有天然骨的三维结构；扫描电镜和倒置相差显微镜均显示复合培养的成骨细胞在材料表面和孔隙内生长良好。结论 WO-1生物衍生骨复合材料具有良好的细胞相容性。     

The fate of soft callus chondrocytes during long bone fracture repair.

Following fracture, the cartilaginous tissue of the soft callus is eventually replaced by bone. Removal of the cartilage is a critical part of the bone healing process but information concerning the changes in chondrocytes during this process is sparse. The aim of the study was to investigate the fate of chondrocytes in the soft callus during the bone repair process using a rabbit tibial fracture model. Fracture tissue was processed for collagen I-III and keratan sulphate immunohistochemistry to study changes in matrix composition and the TUNEL technique (terminal deoxynucleotidyl transferase medicated dUTP nick-end labelling) to identify death of soft callus chondrocytes. Transmission electron microscopy (TEM) was also carried out to investigate the ultrastructure of chondrocytes within the soft callus. Results showed that the size of the cartilage area decreased over time and that cartilage matrix was replaced with new matrix rich in collagen I and III. Chondrocytes became engulfed in the new matrix and appeared to stop producing cartilage matrix. Chondrocyte cell death was seen at the border of the soft callus, just within the newly produced matrix. TEM revealed that these dying/dead cells were not typically apoptotic in appearance. In conclusion, results indicate that chondrocytes of the soft callus die as a result of the progressive production of bone matrix which eventually engulfs them and leads to the remodelling of the area and eventual bone repair.     

Variation of collagen fiber alignment in a joint surface: a scanning electron microscope study of the tibial plateau in dog, rabbit, and man

To determine if articular cartilage collagen fiber organization differs with location on the tibial plateau, specimens from dogs, humans, and rabbits were studied by scanning electron microscopy. Joint surfaces were fixed, dehydrated, and fractured radially so that the periphery could be compared with the center on single specimens. Generally, fibers were more tightly packed in the lateral side than in the medial and the periphery as compared with the center, where the cartilage was consistently thicker and the radial zone was dominant and composed of straight vertical fibers. In the periphery, the tangential and transitional zones were better developed and contributed up to 50% of the cartilage depth in comparison to only 5% centrally. The soft, dull, malacic appearance of the center results from lack of a true surface layer of tangential collagen fibers.     

Comparative study of deflazacort,a new synthetic corticosteroid,and dexamethasone on the synthesis of collagen in different rat bone cell populations and rabbit articular chondrocytes

Summary Deflazacort is a new synthetic glucocorticoid which is an oxazoline derivative of prednisolone. In previous studies, it was shown that deflazacort, depending on the test model used, not only showed considerably more antiinflammatory potency than prednisolone in animals but also caused less deleterious effects on bone mineral metabolism than equivalent amounts of other glucocorticoids in man. In this study, we have compared the effects of deflazacort with those of dexamethasone on the synthesis of collagen in various rat bone cell populations and chondrocytes. Three bone cell populations were prepared by sequential time-dependent collagenase treatment of 1-day-old rat calvaria. Each cell population was further purified on a Percoll gradient (10–90%) yielding three populations of which two are different in alkaline and acid phosphatase and response to parathyroid hormone. A 3-day treatment of bone cell populations with deflazacort and dexamethasone (10⁻¹¹-10⁻⁵ M) revealed that both glucocorticoids, although at different concentrations, inhibited collagen synthesis. 21-desacetyl-deflazacort (5β, 11β, 16β)- 11,21-dihydroxy-2′-methyl-5-H-pregna-1-enol[17,16-d]oxazole-3,20-dione), the presumably active form of the steroid, which is formedin vivo after administration, produced nearly identical results as its precursor. Glucocorticoid concentrations at which inhibition was initially observed were 10⁻⁹ M and 10⁻⁷ M for dexamethasone and deflazacort respectively. Inhibition of collagen synthesis was significantly impaired only in cells isolated from bone during early tissue digestion, and not in those obtained during extensive collagenase treatment. Chondrocytes isolated from articular cartilage of 3-month-old rabbits and grown in primary cultures did not respond to either steroid. However, when passed and grown in secondary culture, collagen synthesis was inhibited considerably more by dexamethasone than by deflazacort. It is apparent that both deflazacort and dexamethasone, although at different concentrations, inhibit collagen synthesis in a differential manner. The lesser deterrent effect of deflazacort may be of clinical importance.