高生物诱导活性复合人工骨整复骨缺损的实验研究

在建立家兔尺骨节段性骨缺损动物模型的基础上，首次采用羟基磷灰石－骨形成蛋白－胶原和羟基磷灰石－胶原两种不同复合人工骨材料分别整复骨缺损，经Ｘ线、大体、体视显微镜及组织学观察结果证实、ＨＡ－ｂＢＭＰ－Ｃ为复合人工骨骨有良好的组织相容性和显著的相诱导及骨引导作用在植入整复骨缺损区，其促使新骨形成的速度、数量和质量均显著优于ＨＡ－Ｃｏ复合人工骨，显示出良好的应用前景。     

应用骨组织工程技术修复节段性骨缺损的研究进展

目前临床上治疗节段性骨缺损仍以自体骨移植方式为主,该方法存在一些问题。应用骨组织工程技术修复节段性骨缺损的研究已经广泛开展,从最初的单纯材料修复到细胞复合材料,再到后来的对种子细胞进行转基因修饰,以及对不同种子细胞、不同材料、不同成骨因子的成骨效果进行评估,研究不断深入并显示出了骨组织工程技术应用于修复节段性骨缺损的巨大潜力。     

改性后的骨形态发生蛋白-2聚乳酸纳米微球缓释系统促进下颌骨缺损修复的研究

目的 探讨改性后聚乳酸（PLA）包裹骨形态发生蛋白-2（BMP-2）制备的纳米微球缓释系统对兔下颌骨缺损的修复效果。方法 将PLA进行接枝聚合反应改性后,应用超声乳化法制备PLA纳米微球（PLA-N）、BMP-2-PLA 纳米微球（BMP-2-PLA-Ns）凝胶。将45只家兔随机分为3组：空白组、PLA-Ns凝胶组（对照组）、BMP-2-PLA-Ns凝胶组（实验组）,建立骨缺损动物模型,对照组植入PLA-Ns凝胶,实验组植入BMP-2-PLA-Ns凝胶,空白组不予特殊处理。术后第1、2、4周处死家兔,截取缺损区颌骨段,进行影像学、苏木精-伊红（HE）染色、PCNA免疫组织化学染色观察。结果 影像学观察可见：实验组骨缺损区修复良好,阴影不明显,修复效果好于对照组和空白组。HE染色观察可见：实验组和对照组有大量新生血管和继发性骨痂形成,实验组骨痂比例明显高于对照组和空白组。免疫组织化学观察可见：第1、2周,实验组PCNA阳性软骨细胞多于对照组和空白组;第4周,各组PCNA阳性细胞均罕见,PCNA阳性细胞检出率低于第1、2周。结论 BMP-2-PLA-NS缓释系统能明显促进下颌骨缺损修复。     

Effects of bone morphogenetic protein-6 on periodontal wound healing in a fenestration defect of rats

BACKGROUND: Bone morphogenetic proteins (BMPs) may play significant roles in bone formation. The ability of BMP-6 to promote wound healing has been chosen as the subject of this investigation. In this study, a synthetic rat BMP-6 polypeptide was applied to a periodontal fenestration defect in rats to elucidate the effects of BMP-6 on periodontal wound healing. MATERIAL AND METHODS: Following surgery to create a bony window on the buccal aspects of mandibular molar roots, 24 male Sprague Dawley rats were divided into four groups according to BMP application (0, 1, 3 and 10 microg, respectively). Animals were killed after 28 days and the mandible taken for histological examination. Histometric measurements were performed on sections selected from three levels (coronal, middle and apical levels; with 240 microm apart from the central) of the defect. New bone and cementum formation (including area and thickness) were analyzed and compared. RESULTS: In general, minimal new bone was observed on the surgically created defects in the non-BMP group, whereas a complete osseous healing occurred in all BMP-6 treated animals. New bone formation (both in area and thickness) was significantly influenced by both the dosage and the examining level, whereas new cementum formation was affected by dosage only. An increase in bone and cementum formation was noted in all three BMP groups when compared with the control group at all examined levels. Among the BMP groups, greatest new bone and cementum formation were noted in the 3 microg group. New cementum thickness increased on the cementum surfaces of the defects compared with the dentinal surfaces in all study groups. CONCLUSION: An increase in new bone and cementum formation was noted after applying a synthetic BMP-6 polypeptide to a periodontal fenestration defect in rats. Therefore, we suggest that BMP-6 may play a certain role in periodontal regeneration.     

糖尿病对大鼠牙槽骨缺损修复中骨形态发生蛋白-2表达影响的研究

目的 观察糖尿病(diabetes mellitus,DM)对实验性大鼠牙槽骨缺损修复过程中不同时期骨形态发生蛋白-2(bonemorphogenetic protein-2,BMP-2)表达的影响。方法 将48只雄性SD大鼠随机分为DM组和对照组,每组24只,DM组大鼠经腹腔注射链脲佐菌素造成DM大鼠模型,建模成功后行大鼠牙槽骨骨缺损制备,2组均分别于骨缺损制备后1、2、4、8周各取6只大鼠处死,取术区组织。苏木精-伊红染色(hematoxylin-eosin staining,HE染色)镜下观察缺损区内新生骨样组织形成情况;用免疫组化法检测术后1、2、4、8周缺损区内BMP-2的表达情况,比较各组的平均光密度。结果 HE染色观察显示DM组成骨较对照组减少。术后1周、2周免疫组化观察对照组新骨BMP-2的表达强于DM组,二者之间差异有统计学意义(P<0.05),术后4周、8周对照组BMP-2表达较之前弱,但与DM组二者之间差异无统计学意义(P>0.05)。结论 DM影响了大鼠牙槽骨缺损的修复,可能是DM使BMP-2形成减少,从而抑制了未分化间充质向成骨细胞的转化,从而影响种植体骨结合,降低种植初期稳定性。?     

牛骨形成蛋白（bBMP）体内骨诱导活性的实验研究

参照中甲的从小牛骨基质中提取亍骨形成蛋白（ｂＢＭＰ）,经ＳＤＳ－ＰＡＧＥ电泳分析,ｂＢＭＰ含６７、４３、３０、２２、１８笔１４ｋＤ六种蛋白组分,保贸ＢＭＰ生蛋白成份,植入小鼠股部肌肉后的Ｘ线及组织学观察发现,所提取的ｂＢＭＰ具有较高的骨诱导活性,ｂＢＭＰ植入后１４天即可见有新骨形成,２１ 有含骨髓的支状骨形成。采用ｂＢＭＰ具有较高的骨诱地活性,采用ｂＢＭＰ单克隆抗体的免疫组织化学染色发现,ＢＭＰ存     

Efficacy of bone morphogenetic protein (BMP) with osteopromotive membranes – an experimental study in rat mandibular defects

The effect of bone morphogenetic protein (BMP) on healing of standardized bone defects was studied with and without the placement of osteopromotive membranes. Two different bovine BMP (bBMP) preparations were tested. These contained primarily collagen as a carrier. Standardized transosseous bone defects, 5 mro in diameter, were created in mandibles of rats. If left untreated, such "critical size defects" never heal during the lifetime of the animal, whereas covering with an osteopromotive membrane is known to cause complete healing of the defects in 6 weeks. The bBMP was implanted in defects and were either covered with an expanded polytetrafluoroethylene (e-PTFE) membrane (GORE–TEX®) or were left uncovered. Control defects did not receive any bBMP and were either covered with membrane or were left uncovered. Histological evaluation was made after 12 d and 24 d of healing, respectively. Implantation of bBMP alone was associated with formation of voluminous amounts of new bone, resulting in essentially complete defect healing at 24 d. However, the combination of membrane and bBMP was dearly less effective in stimulating bone healing, being only about as efficient as when using membranes alone. It was concluded that whereas both bBMP preparations were strongly osteoinductive, no further improvement of bone healing was seen when the membrane technique was supplemented with bBMP, compared to membrane alone. An explanation may be that the presence of an e-PTFE membrane prevents the degradation of the carrier material in the preparations, thus strongly reducing the availability of bBMP.     

Bio-Oss骨复合富血小板纤维蛋白修复兔牙周骨缺损

目的探讨组织工程骨Bio-Oss骨复合富血小板纤维蛋白（PRF）修复牙周骨缺损中骨形成蛋白2（BMP-2）、骨保护素（OPG）和核因子κB受体活化因子配体（RANKL）的表达及意义。 方法3月龄雄性新西兰大白兔36只,采用随机数表法分为4组,每组9只,制备单侧牙周骨缺损模型,于骨缺损处分别植入Bio-Oss骨（Bio-Oss组）、PRF（PRF组）和Bio-Oss/PRF复合物（Bio-Oss/PRF组）,以未植入任何材料者作为空白对照。术后4、8和12周处死动物,行大体观察、Masson染色及BMP-2、OPG、RANKL免疫组化观察,并对其表达进行析因设计的方差分析。 结果Masson染色结果显示,Bio-Oss/PRF组术后8周时见部分成熟骨,12周见骨板形成,骨成熟度较高。析因分析显示Bio-Oss组在4、8和12周时BMP-2表达量逐渐增高,差异有统计学意义（F = 51.30,P<0.001）;OPG表达量随时间延长先升高后减低,差异有统计学意义（F = 167.03,P<0.001）;RANKL表达量随时间延长逐渐减低,差异有统计学意义（F = 5.39,P = 0.046）。PRF组在4、8和12周时BMP-2表达量无统计学意义（F = 0.68,P = 0.544）;OPG和RANKL表达量随时间延长逐渐减低,差异有统计学意义（F_OPG = 1070.93,P_OPG<0.001;F_RANKL = 2306.15,P_RANKL<0.001）。Bio-Oss/PRF组在4、8和12周时BMP-2、OPG和RANKL表达量逐渐降低,差异有统计学意义（F_BMP-2 = 13.29,P_BMP-2<0.001;F_OPG = 237.91,P_OPG<0.001;F_RANKL = 132.48,P_RANKL<0.001）。空白对照组在4、8和12周时BMP-2和OPG表达量先升高后减低,差异有统计学意义（F_BMP-2 = 88.33,P_BMP-2<0.001;F_OPG = 30.06,P_OPG<0.001）,RANKL表达量随时间推移逐渐减低,差异有统计学意义（F = 56.52,P<0.001）。 结论Bio-Oss骨复合PRF应用可促进成骨以修复牙周骨缺损。     

The use of tissue-engineered bone with human bone morphogenetic protein-4-modified bone-marrow stromal cells in repairing mandibular defects in rabbits

In this study, the capacity of hBMP-4 gene therapy combined with tissue-engineering techniques to improve the repair of mandibular osseous defects in rabbits was explored. A mammalian plasmid vector expressing enhanced green fluorescent protein-human bone morphogenetic protein-4 (pEGFP-hBMP-4) was initially constructed through subcloning techniques. Bone-marrow stromal cells (bMSCs) from New Zealand White rabbits were cultured and either transfected with pEGFP-hBMP-4 or pEGFP, or left untransfected in vitro. Once the transfer efficiency was determined through the expression of EGFP, cells from the three groups were combined with natural non-organic bone (NNB) at a concentration of 50 x 10(6)cells/ml and placed in 15 mm x 6 mm bilateral, full-thickness, mandibular defects surgically made in 12 rabbits. Together with NNB control, there were six samples per group. Four weeks after surgery, the implants were harvested and evaluated histomorphologically. Under optimal experimental conditions, gene transfer efficiency reached a maximum of 38.2+/-9.4%. While the percentage of new bone area in the NNB control group was 8.8+/-3.1%, in the untransfected bMSC group 22.5+/-8.2%, and in the pEGFP group 18.1+/-9.0%, a significantly higher amount of 32.5+/-6.1% was observed in the pEGFP-hBMP-4 group. These results suggest that transfection of bMSCs with hBMP-4 enhances their inherent osteogenic capacity for maxillofacial bone tissue-engineering applications.     

重组人骨形成蛋白-2和牛骨形成蛋白骨诱导活性的比较研究

将５００μｇ重组人骨形成蛋白－２和５００μｇ牛骨形成蛋白以胶原作为载体分别植入同一ＳＤ大鼠两侧股部肌肉内。取材后进行组织学观察和钙含量测定。     

脱矿牙本质基质材料在颌骨骨缺损修复的应用

颌骨缺损会导致颌面部的功能及形态的异常。所以术后的骨缺损修复是必要的。为了避免自体骨移植所带来的二次创伤,寻找优良的骨替代材料是目前的研究热点。牙本质材料因为其易获取,制备简单,成骨效果良好而获得许多关注。并且学者发现脱矿后的牙本质成骨能力更为显著。该文将对脱矿牙本质材料的成骨基质及临床应用作一综述。