多孔双相陶瓷复合重组人骨形态发生蛋白-2和碱性成纤维细胞生长因子缓释微球的生物相容性

目的 观察复合重组人骨形态发生蛋白-2(rhBMP-2)和碱性成纤维细胞生长因子(bFGF)缓释微球的多孔双相陶瓷(BCP)组织相容性.方法 A组(rhBMP-2+bFGF缓释微球/BCP)、B组(单纯BCP)、C组(bFGF缓释微球/BCP)、D组(rhBMP-2缓释微球/BCP)和E组(不含BCP).其中bFGF、dlBMP的浓度各为5、15μg,材料均为5 mm×5 mm×1mm.采用体外细胞培养的方法测定细胞黏附能力、浸提液对于兔骨髓基质细胞(BMSCs)增殖和成骨分化的影响及体外诱导BMSCs成骨分化的能力.结果 细胞在材料上黏附、生长良好.各组噻唑蓝(MTT)吸光度值、碱性磷酸酶(ALP)值均随培养时间的延长而增大.A组与B、D和E组比较对MSC有显著的促增殖作用,但低于C组(P<0.05).A组ALP活性显著高于B、C和E组,但低于D组(P<0.05).结论 复合rhBMP-2和bFGF缓释微球的BCP具有良好的生物相容性.     

牵张成骨术整复猕猴腭裂骨桥蛋白与骨钙蛋白表达研究

Objective To study the mechanism of new bone formation and remodeling of distraction osteogenesis(DO) by analysis of the expression of osteopotin(OPN)and osteecalcin(OC). Methods Rhesus were operated to reconstruct the animal model of cleft palate(CP). The CP was closed by DO in experimental group(n=21). After consolidation of 1, 2, 4, 6, 8, 12, 24 weeks, every 3 animals were killed to collect the specimens, respectively. The OPN and OC and their mRNA were detected quantitatively by Real-time RT-PCR and ELISA, respectively. The animals in control group(n=2) and sham group(n=2) were used as control. Results The mRNA expression of OPN increased since 2nd week of consolidation and reached the peak at 4th week(7.59±0.37). The mRNA expression of OC was up-regulaed since 4th week, and reach the peak at 6th week(7.94±0.31). Then they decreased to about the level in sham group at 24th week(P > 0.05). The OPN and OC were highly expressed during 4 to 6 weeks of consolidation. During 8 to 12 weeks, they decreased like their mRNA expression. Conclusion The intramembraneons new bone formation after DO can reconstruct the bone defect of CP. The new formed bone can be remodeled to be quite normal bone tissue.     

Effect of nano-hydroxyapatite／collagen composite and bone morphogenetic protein-2 on lumbar intertransverse fusion in rabbits

Objective: To investigate the effect of nanohydroxyapatite/collagen (nHA/collagen) composite as a graft extender and enhancer when combined with recombinant human bone morphogenetic protein-2 (rhBMP-2) on lumbar intertransverse fusion in rabbits. Methods: Sixty-four adult female New Zealand white rabbits, aged 1 year and weighing 3.5-4.5kg, underwent similar posterolateral intertransverse process arthrodesis and were randomly divided into 4 groups based on different grafts: autogenous cancellous bone alone (ACB group), nHA/collagen alone ( HAC group ), half autogenous cancellous bone and half nHA/collagen (ACB HAC group) and nHA/collagen combined with rhBMP-2 (HAC BMP group ). The fusion masses were analyzed by manual palpation, radiography, biomechanical testing and histological examination. Results: Fusion was observed in 4 cases in the 6th week and in 5 cases in the 10tb week after surgery in ACB group. No case showed fusion in HAC group. In ACB HAC group, there was fusion in 3 cases in the 6th week and in 4 cases in the 10th week after surgery. In HAC BMP group, fusion in 1 case was found in the 4th week, in 5 cases in the 6th week and in 6 cases in the 10th week after surgery. It suggested that ACB, ACB HAC and HAC BMP groups showed similar fusion ratio and mechanical strength in the 6th and 10th week after surgery. According to the microstructure analysis of the samples, nHA/collagen had no negative effect when implanted together with ilium autograft. In HAC BMP group, new bone-like tissue was observed in the 2nd week postoperatively, and nearly all of the implanted composites were replaced by mature bone matrix and new bones in 10th week postoperatively. Conclusions：The nHA/collagen, especially combined with rhBMP-2, is a promising bone substitute, for it has quick biodegradation, fine bone-bending ability, and high osteoconductivity on posterolateral spinal fusion in rabbits.     

组织工程骨联合外固定修复大鼠股骨节段性骨缺损

目的 观察以外固定器固定,骨髓间充质干细胞 (BMSCs) 联合双相磷酸钙(BCP)修复大鼠股骨节段性骨缺损的效果.方法 A组:BMSCs与BCP复合植入缺损区;B组:BCP植入缺损区;C组:空白组.定期摄X线片,术后12周取材.结果 A组随时间延长X线评分递增,12周时平均为4.17分,B组为1.18分,C组为1.08分,差异有统计学意义(P<0.05).组织学检查见A组缺损区有大量的新生骨生成,而B、C组无新生骨生成.A组的抗压刚度和扭转刚度分别为(8.09±2.42)N/mm、(1.89±0.72)Nmm/deg;B组为(1.75±0.90)N/mm、(0.40±0.21)Nmm/deg,差异有统计学意义(P<0.05).结论 组织工程骨联合外固定可以修复节段性骨缺损.

Abstract：

Objective To evaluate the efficacy of bone mesenchymal stem cells (BMSCs) combined with biphasic calcium phosphate (BCP) repair of segmental bone defect, which was stabilized with an adaptable external fixation system.Methods In group A, the femoral defect was filled with BCP combined with BMSCs; In group B, the femoral defect was filled with BCP, and in group C, defects were left empty. Animals were sacrificed 12 weeks post-operation.Results In group A, radiographic scores were average 4.17, significantly (P<0.05) greater than in group B (1.18) and group C (1.08). Histological evaluations displayed the bridging of the defect in group A, with remarkable new bone formation. In contrast, group B and group C showed no formation of new bone. The mechanical testing revealed that axial stiffness was (8.09±2.42) N/mm and torsional stiffness was (1.89±0.72) Nmm/deg in group A, and those in group B were (1.75±0.90) N/mm and (0.40±0.21) Nmm/deg respectively. There was significant difference in biomechanical tests between group A and group B (P<0.05).Conclusion External fixator combined with tissue engineered bone can repair segmental bone defect.     

碱性成纤维细胞生长因子缓释微球治疗兔膝骨关节炎的实验研究

目的 研究壳聚糖包被碱性成纤维细胞生长因子(bFGF)的缓释微球对实验兔膝关节骨性关节炎的治疗作用.方法 2008年11月至2009年7月,选取健康成年新西兰大白兔54只,随机分成6组:对照组、模型组、PBS微球组(PBS-M)、bFGF溶液组(bFGF-S)、10μgbFGF微球组(10-bFGF-M)及100μg bFGF微球组(100-bFGF-M).膝关节腔内注射木瓜蛋白酶建立兔膝骨关节炎模型(对照组除外).除模型组外其余各组分别于建模后第3周和第6周于关节腔内注射1ml干预液,分别含PBS微球、bFGF溶液、10μg bFGF微球及100μg bFGF微球.于第9周处死动物后取材,通过大体及组织病理学检查评价实验结果.结果 根据Ink评分及Mankin评分结果,模型组关节软骨损伤程度重于对照组(t=8.22,P=0.00;t=17.20,P=0.00),PBS-M组、bFGF-S组的关节软骨损伤程度与模型组近似(Ink评分:t=0.26,P=0.79;t=0.80,P=0.45;Mankin评分:t=1.51,P=0.17;t=0.56,P=0.60),而10-bFGF-M组和100-bFGF-M组关节软骨损伤程度较模型组明显减轻(Ink评分:t=3.58,P=0.01;t=6.82,P=0.00;Mankin评分:t=3.41,P=0.01;t=5.00,P=0.00).100-bFGF-M组与10-bFGF-M组相比关节软骨损伤程度明显减轻(t=50.29,P=0.00;t=2.80,P=0.02).结论 bFGF缓释微球能维持bFGF关节腔内的有效浓度,可能通过加速蛋白多糖的合成并抑制其分解等作用机制逆转了关节软骨损伤的病理过程.

Abstract：

Objective To study the therapeutic effect of chitosan-coated basic fibroblast growth factor (bFGF) slow-releasing microspheres on the knee osteoarthritis in the rabbit. Methods From November 2008 to July 2009, 54 New Zealand rabbits were divided into 6 groups at random, which were the control group, the model group, the PBS-M group, the bFGF-S group, the 10-bFGF-M group and the 100-bFGF-M group, respectively. The model of knee osteoarthritis was induced by the injection of papain in the rabbit. Except the control and model groups, all the experimental groups were implanted 1 ml intervention solution at the third and sixth weeks, including the PBS microspheres, bFGF solution, 10 pμg bFGF microspheres and 100 μg bFGF microspheres, respectively. The rabbits were sacrificed at the ninth week after operation, and then articular cartilage was conducted the morphological and histopathological evaluation. Results The damage of articular cartilage in the model group was more serious than that in the control group, with statistical differences according to the Ink score (t = 8. 22, P = 0. 00) and Mankin score (t = 17. 20, P =0. 00). The damage of articular cartilage in the PBS-M and bFGF-S groups were similar with that in the model group, according to the Ink score (t =0. 26, P =0. 79; t =0. 80, P =0.45) and Mankin score (t =1.51, P=0. 17; t =0.56, P=0.60). The Ink and Mankin scores in the 10-bFGF-M and 100-bFGF-M groups were better than that in the model group (Ink score: t =3.58, P =0. 01; t =6. 82,P=0.00; Mankin score: t =3.41, P=0.01; t =5.00, P=0.00), with the 100-bFGF-M group much better (t =5.29, P =0. 00; t =2. 80, P =0. 02). Conclusions The bFGF slow-releasing microsphere can keep its effective intra-articular concentration, which may accelerate the synthesis of protcoglycan and inhibit its decomposition to reverse the damage of articular cartilage.     

Preparation and in vitro activity of controlled release microspheres incorporating bFGF

Objective： To study the preparative method of controlled release microspheres incorporating basic fibroblast growth factor （bFGF） and the bioaetivities of bFGF, which were released from bFGF mierospheres, on the cultured Sehwann cells.
Methods： bFGF was microcapsulated with the multiple emulsion encapsulative method using polylactic-coglycolic acid （PLGA） as coating material. Its morphology, particle size distribution, drug loading, enveloping rate and in vitro release property were studied. The cultured Schwann cells were grouped according to the different ingredients being added to the culture medium of bFGF group or bFGF-PLGA group. Then the cytometry, cytoactivity detection and mitotic cycle analysis of Schwann cells were performed.
Results： The morphology and the particle size distribution of the bFGF-PLGA microspheres were even and good. The drug loading and enveloping rate of microspheres were （ 27.18×10^-3 ） % ± （0.51×10^-3） % and 66.43 % ± 1.24 %. The release property of microspheres in vitro was good and the overall release rate was 72. 47 % in 11 days. The in vitro cellular study showed that： at the first 2 days of plate culture, the cell number and viability of the bFGF group were statistically higher than the bFGF-PLGA group; at the 3rd and 4th days of plate culture, the cell number and viability of bFGF and bFGF-PLGA groups showed no difference; at the 6th and 8th days of the plate culture, the cell number and viability of the bFGF-PLGA group were statistically higher than the bFGF group. By flow eytometry examination, at the 2nd day of plate culture, the G2/M ＋ S percentage of bFGF group was statistically higher than the bFGF-PLGA group, at the 4th and 8th days of plate culture, the G2/M ＋ S percentage of the bFGF-PLGA group was statistically higher than the bFGF group.
Conclusions： It is practical to prepare the bFGF- PLGA microspheres with the multiple emulsion eneapsulative method, bFGF-PLGA mierospheres can preserve the bioaetivities of bFGF effectivel     

电穿孔介导的基因治疗对兔下颌骨牵引区新生骨骨密度与强度的影响

Objective To explore the effect of electroporation mediated gene therapy on bone mineral density and strength of new-formed bone in mandibular distraction gap, so as to enhance the osteogenesis and shorten the distraction term. Methods New-Zeland rabbits were employed. The distraction began after 3 days of latency period at the rate of 0. 8 mm per day for 7 days. After distraction, the rabbits were randomly divided into 5 groups to receive injection in the distraction gap with recombinant plasmid 2 μg(0. 1μg/μl)pIRES-hVEGF165-hBMP2 in group A, with recombinant plasmid pIRES-hBMP2 in group B, with recombinant plasmid pIRES-hVEGF165 in group C, with pIRES in group D, and with normal saline (NS) in group E. After injection, electroporation was performed in all the groups. After 1 week, 2 weeks, 4 weeks and 8 weeks of consolidation, all the animals underwent X-ray and quantitative computed tomography (QCT). The new-formed bone in distraction gap was selected as regions of interest (ROI) to measure the bone mineral density( BMD). Then the rabbits were sacrificed and the new-formed bone samples were harvested to detect 3-point crushing strength. Results BMD of newly formed bone in group A, B and C was markedly higher than that in group D and E (P < 0. 01 ). After 2 weeks of consolidation, BMD in group A was much higher than that in the other groups, but there was no difference between group B and C. After 4 weeks of consolidation, BMD in group A and B was markedly higher than that in group C, D and E ( P < 0. 01 ). After 8 weeks of consolidation, BMD in group A was markedly higher than that in the other groups. While the BMD was not significantly different between group B and C, but the BMD in group B and C was higher than that in group D and E ( P < 0. 01 ). After 4 weeks of consolidation, the 3-point crushing strength of newly formed bone in group A was markedly higher than that in group B,C, D and E ( P < 0. 01 ) , which was still the same after 8 weeks of consolidation. And the crushing strength in group B was higher than that in group C, D and E ( P < 0.05 ). Conclusions Electroporation-mediated transfection of recombinant plasmid pIRES-hVEGF165-hBMP2 could greatly enhance osteogenesis and calcification. A combination of VECF and BMP may promote osteogenesis and angiogenesis simultaneously, so as to magnify the effect of each growth factor, resulting a synergetic effect.     

电穿孔介导的基因治疗对兔下颌骨牵引区新生骨骨密度与强度的影响

Objective To explore the effect of electroporation mediated gene therapy on bone mineral density and strength of new-formed bone in mandibular distraction gap, so as to enhance the osteogenesis and shorten the distraction term. Methods New-Zeland rabbits were employed. The distraction began after 3 days of latency period at the rate of 0. 8 mm per day for 7 days. After distraction, the rabbits were randomly divided into 5 groups to receive injection in the distraction gap with recombinant plasmid 2 μg(0. 1μg/μl)pIRES-hVEGF165-hBMP2 in group A, with recombinant plasmid pIRES-hBMP2 in group B, with recombinant plasmid pIRES-hVEGF165 in group C, with pIRES in group D, and with normal saline (NS) in group E. After injection, electroporation was performed in all the groups. After 1 week, 2 weeks, 4 weeks and 8 weeks of consolidation, all the animals underwent X-ray and quantitative computed tomography (QCT). The new-formed bone in distraction gap was selected as regions of interest (ROI) to measure the bone mineral density( BMD). Then the rabbits were sacrificed and the new-formed bone samples were harvested to detect 3-point crushing strength. Results BMD of newly formed bone in group A, B and C was markedly higher than that in group D and E (P < 0. 01 ). After 2 weeks of consolidation, BMD in group A was much higher than that in the other groups, but there was no difference between group B and C. After 4 weeks of consolidation, BMD in group A and B was markedly higher than that in group C, D and E ( P < 0. 01 ). After 8 weeks of consolidation, BMD in group A was markedly higher than that in the other groups. While the BMD was not significantly different between group B and C, but the BMD in group B and C was higher than that in group D and E ( P < 0. 01 ). After 4 weeks of consolidation, the 3-point crushing strength of newly formed bone in group A was markedly higher than that in group B,C, D and E ( P < 0. 01 ) , which was still the same after 8 weeks of consolidation. And the crushing strength in group B was higher than that in group C, D and E ( P < 0.05 ). Conclusions Electroporation-mediated transfection of recombinant plasmid pIRES-hVEGF165-hBMP2 could greatly enhance osteogenesis and calcification. A combination of VECF and BMP may promote osteogenesis and angiogenesis simultaneously, so as to magnify the effect of each growth factor, resulting a synergetic effect.     

牵张成骨术整复猕猴腭裂后胰岛素样生长因子-1与碱性磷酸酶表达研究

Objective To investigate the osteogenesis mechanism by analysis of the expression of insulin-like growth factor-I (IGF-1)and alkaline phesphatas (ALP)in the reconstruction of cleft palate(CP) with distraction osteogenesis (DO) in rhesus. Methods The CP animal models were established surgically. 21 rhesus in experimental group underwent DO to close the soft and bony defect, followed by consolidations. Every 3 animals were killed and the specimen were taken out after consolidation of 1, 2, 4, 6, 8, 12, 24 weeks. The mRNA of IGF-1 and ALP were detected with Real-time BT-PCB technique. The expression of IGF-1 and ALP was quantitatively analyzed by ELISA. The results were compared with those in control and sham groups (each of 2 animals), respectively. Results Since consolidation, the mRNA of IGF-1 and ALP increased significantly at one week and reached the peak at two weeks, but decrease to control level after 12 weeks of consolidation. The expression of IGF-1 also increased to peak level afiert two weeks of consolidation. The expression of ALT increased significantly since consolidation and reach the peak value after six weeks. They all decreased to nearly control level after 8 ～ 12 weeks. Conclusions The palate cleft can be successfully closed with new formed bone after DO. The mechanism of bone consolidation is intramembranons bone formation.     

牵张成骨术整复猕猴腭裂后胰岛素样生长因子-1与碱性磷酸酶表达研究

Objective To investigate the osteogenesis mechanism by analysis of the expression of insulin-like growth factor-I (IGF-1)and alkaline phesphatas (ALP)in the reconstruction of cleft palate(CP) with distraction osteogenesis (DO) in rhesus. Methods The CP animal models were established surgically. 21 rhesus in experimental group underwent DO to close the soft and bony defect, followed by consolidations. Every 3 animals were killed and the specimen were taken out after consolidation of 1, 2, 4, 6, 8, 12, 24 weeks. The mRNA of IGF-1 and ALP were detected with Real-time BT-PCB technique. The expression of IGF-1 and ALP was quantitatively analyzed by ELISA. The results were compared with those in control and sham groups (each of 2 animals), respectively. Results Since consolidation, the mRNA of IGF-1 and ALP increased significantly at one week and reached the peak at two weeks, but decrease to control level after 12 weeks of consolidation. The expression of IGF-1 also increased to peak level afiert two weeks of consolidation. The expression of ALT increased significantly since consolidation and reach the peak value after six weeks. They all decreased to nearly control level after 8 ～ 12 weeks. Conclusions The palate cleft can be successfully closed with new formed bone after DO. The mechanism of bone consolidation is intramembranons bone formation.     

三种钙磷陶瓷材料复合重组人骨形成蛋白-2体内成骨的研究

目的 探讨和比较3种钙磷陶瓷材料HA、TCP、HA／TCP复合重组入骨形成蛋白。2(rhBMP—2)体内异位成骨效果，为临床应用提供依据。方法 取35只3月龄Wistar大鼠，将复合rhBMP—2的3种钙磷陶瓷材料(1：1)植于鼠背部肌袋内，未复合rhBMP-2的上述3种单纯陶瓷材料为对照组。术后2、4和8周取材，测定植入物碱性磷酸酶(ALP)活性，通过HE染色和计算机图像分析进行组织学和组织计量学观察，比较新生骨组织的形成。结果 术后2、4周复合植入物ALP活性测定从高到低依次为HA、HA／TCP、TCP，但在相同rhBMP—2剂量下，其差异无统计学意义(P＞0．05)，与相对应单纯支架材料比较有统计学意义(P＜0．05)；组织学和组织计量学检测结果显示各复合材料组均有新骨形成，成骨量随时间推移而增加，2周时以HA/rhBMP—2成骨量较多，但3组间差异无统计学意义(P＞0．05)；8周时新骨形成以双相陶瓷HA／TCP最佳，相关参数和图像分析有统计学意义(P＜0．05)，成骨量8周较2、4周多，有统计学意义(P＜0．01)；3种单纯支架材料各观察期均无骨样组织形成。结论 双相陶瓷材料HA／TCP是携带rhBMP—2的钙磷陶瓷良好支架材料。     

多孔磷酸钙人工骨与重组人骨形成蛋白2复合修复骨缺损的实验研究

目的研究多孔磷酸钙人工骨（porous calcium phosphate cement，PCPC）与重组人骨形成蛋白2（recombinant human bone morphogenetic protein2，rhBMP-2）复合后体外的缓释作用及其对兔骨缺损的修复作用。方法采用物理吸附法将rhBMP-2（0．4mg）溶液吸附至PCPC中，制备成PCPC／rhBMP-2复合材料。冻干后，扫描电镜观察复合材料内部形态。以包覆壳聚糖的PCPC／rhBMP-2为实验组，单纯PCPC／rhBMP-2为对照组，测试在模拟体液中的rhBMP-2缓释行为。取新西兰大白兔12只，股骨远端制成直径4．2mm，深5．0mm的骨缺损模型。将包覆壳聚糖的PCPC／rhBMP-2复合材料修复骨缺损作为实验组，以植入单纯PCPC作为对照组。术后观察动物一般情况，于4周和8周取材行X线片和组织学观察。结果扫描电镜显示PCPC／rhBMP-2复合材料孔隙中吸附了大量的rhBMP-2。rhBMP-2体外缓释：对照组rhBMP-2于150h基本全部释放；实验组rhBMP-2于350h缓释量约达99％，较对照组慢。动物实验：动物术后切口无感染，于4周行动自如。X线片示术后4周对照组骨缺损区材料清晰，实验组骨缺损区密度大部分接近宿主骨，材料模糊；8周对照组材料边缘较术后4周模糊，实验组骨缺损区密度已基本接近宿主骨。组织学观察，术后4周对照组可见少量成骨细胞和破骨细胞，实验组可见成熟骨组织和骨髓腔，新生骨逐渐取代材料；8周对照组可见大量成骨细胞和破骨细胞，少量新生骨并向材料内长入，实验组可见成熟骨小梁和骨髓组织。结论PCPC是rhBMP-2较理想的载体材料，复合后具有良好的诱导成骨作用，可作为一种新型复合人工骨修复骨缺损，具有良好的临床应用前景。     

重组复合异体冻干骨修复节段性骨缺损的实验研究

目的：探讨碱性成纤维细胞生长因子（bFGF）和透明质酸凝胶（HAG）复合异体冷冻干燥骨修复节段性骨缺损的能力及作用机制。方法：用新西兰大白兔50只，两侧桡骨干外造成15mm缺损，采用四种不同的处理方法；A组植入bFGF、HAG与异体冻干骨的复合物；B组植入吸附bFGF的异体冻干骨；C组植入含有HAG的异体冻干骨；D组单纯植入异体冻干骨作为对照，每组肢体数为25，在术后2、4、6、8和10周进行X线片，组织学和放射性核素描检查，并测定钙含量。结果：A组在术后不同时间的骨代谢活性，新骨生成量和钙含量均高于B组（P＜0．05），B组高于C、D组（P＜0．05），C组与D组无明显差异。A组和B组缺损分别于术后8、10周完全愈合，而C、D两组骨缺损在术后10周仍未愈合。结论：b FGF作为一种骨生长因子促进新骨生成；HAG作为缓释载体提高bFGF的效能，它们复合异体冻干骨后能有效提高骨缺损的修复能力     

重组人骨形态发生蛋白-2/异体骨复合骨用于兔腰椎融合的显微CT研究

目的 观察重组人骨形态发生蛋白-2/异体骨复合骨、自体骨与异体骨分别用于兔腰椎融合后,不同时间点融合骨组织微结构的变化.方法 成年雄性新西兰大白兔45只,随机分为3组,每组15只.在每只兔的L5、L6横突间行腰椎后路植骨融合术,各组分别植入复合骨条,自体髂骨条以及单纯异体髂骨条,每组于术后第3、4、5周各处死5只大白兔,分离保存融合节段标本.用显微cT扫描后行骨组织定量分析.结果 术后3个时间点中,复合骨组和自体骨组新生骨小梁的强度和形态均要优于异体骨组且差异有统计学意义(P＜0.05).第3周,复合骨组的组织骨密度(TMD)为(433.98±2.64)mg/cm3,高于自体骨组(424.81±4.69)mg/cm3(P＜0.05);第4周,复合骨组的骨小梁厚度(Tb.Th)为(0.097±0.004)mm,高于自体骨组(0.082±0.003)mm(P＜0.01);第5周,复合组的组织矿含量(TMC)为(7.70±0.30)mg,高于自体骨组(7.00±0.24)mg(P＜0.01).结论 在兔腰椎后路横突间植骨融合中,重组人骨形态发生蛋-2/异体骨复合骨的成骨效应不低于自体骨,优于异体骨.     

多孔载因子CPC促进骨缺损愈合的实验研究

[目的]探讨磷酸钙骨水泥复合rhBMP-2/明胶微球复合材料在治疗骨缺损时的降解、成骨性能。[方法]制备携载rhBMP-2的明胶微球(GMs),与磷酸钙骨水泥(CPC)复合,制备出rhBMP-2/GMs/CPC复合人工骨。取30只新西兰大白兔,在前臂桡骨中段制造人工骨缺损,随机分成3组,分别植入rhBMP-2/GMs/CPC/复合物(A组)、GMs/CPC(B组)、rhBMP-2/CPC(C组),术后6、12周分别进行X线检测、骨密度测定,术后12周处死动物,分别行生物力学测定,脱钙切片、HE染色,不脱钙切片进行荧光显微镜下观察双标间距,计算平均矿化率。[结果]与GMs/CPC、rhBMP-2/CPC组比较,复合材料植入后不同时间点的材料降解及成骨均高于对照组。12周A组标本生物力学实验测定结果表明指标接近正常,与B、C组比较有统计学差异。骨密度12周、新骨矿化率提示有统计学差异。[结论]rhBMP-2/GMs/CPC微球系统复合材料在体内易降解,具有良好成骨活性,是良好的骨修复材料。     

碱性成纤维细胞生长因子复合部分脱蛋白骨修复兔股骨头骨缺损的作用机理及相关性分析

目的:探讨bFGF/PDPB在修复兔股骨头骨缺损过程中成骨与再血管化作用的相关性及其作用机理.方法:成年健康新西兰白兔24只48髋随机分为3组,每组16髋,建立股骨头骨缺损模型,A组植入bFGF/PDPB、B组植入PDPB、C组为空白对照.动物于术后2、4、8周分批处死,并制备墨汁灌注标本,进行组织学和微血管观察及血管密度图像分析,计数成骨细胞数和破骨细胞数,测定骨钙含量,并进行相关性分析.结果:A组骨缺损修复早于B和C组,C组术后8周缺损区仍存在;A组术后8周骨钙含量和血管密度高于B和C组;术后各时点血管密度与成骨细胞数成正相关;与破骨细胞于术后2周成正相关;与骨钙含量于术后2周呈负相关,术后8周呈正相关.结论:bFGF具有成骨和再血管化作用,促进移植材料的爬行替代,在治疗股骨头坏死方面具备一定的潜能和优势.     

骨形态发生蛋白-2壳聚糖微球复合组织工程支架修复兔股骨髁部骨缺损的实验研究

目的 探讨重组人骨形态发生蛋白-2(rhBMP-2)壳聚糖缓释微球复合聚乳酸-聚羟乙酸/磷酸三钙(PLGA/TCP)支架修复骨缺损的可行性和有效性.方法 取健康成年新西兰大白兔45只,在40只实验动物股骨髁部制备0.6 cm×1.0 cm骨缺损.实验分4组:A组:缺损组,B组:用PLGA/TCP空白支架修复骨缺损,C组:用等量rhBMP-2复合PLGA/TCP支架修复骨缺损,D组:用rhBMP-2壳聚糖微球复合PLGA/TCP支架修复骨缺损,每组10只动物.另5只动物为正常对照组(E组).应用X线、Micro-CT和组织病理学等方法检测术后4、12 周各实验组骨缺损修复效果.结果 术后4周X线片示:A组无新骨形成.B组有少量新生骨影像形成,C、D组骨缺损部位均有新骨影像形成.术后12周,Micro-CT结果显示:D组骨密度、骨体积分数、骨小梁厚度、骨小梁数目等指标均优于B组和C组,差异均有统计学意义(P<0.05),A组末检测到上述指标.术后4剧,D组可见大量骨组织形成,有部分成熟的骨小梁,PLGA/TCP支架大部分被降解.吸收.术后12周,D组支架和微球完全降解.骨缺损被成熟骨取代;B、C、D组骨长入率分别为5.78%±1.21%、37.26%±6.45%、74.25%±8.91%,3组之间比较差异均有统计学意义(P<0.05).结论 复合rhBMP-2壳聚糖微球的PLGA/TCP支架具有良好的骨缺损修复效果,临床应用前景较好.     

外源性bFGF对兔下颌骨牵张成骨的影响

目的：研究局部应用外源性碱性成纤维细胞生长因子对兔下颌骨牵张成骨的影响。方法：成年白兔30只,随机分Ⅰ、Ⅱ两组（n=15）,用自制的牵张器延长右侧下颌骨3 mm。牵张部位Ⅰ组给外源性bFGF（0.5ml/天×7天,420U/ml）作为实验组,Ⅱ组给等量生理盐水作对照组,牵张结束后不同时期行X线、定量CT、组织学检查。结果：所有动物右侧下颌骨被成功延长,组织学示：Ⅰ组动物新骨生成的速度和数量优于Ⅱ组;定量CT示：固定早期（2周、4周）Ⅰ组骨密度值明显高于Ⅱ组（P＆lt;0.05）。结论：外源性bFGF早期有促进兔下颌牵张成骨的作用。     

构建组织工程骨修复兔颅骨极限缺损的实验研究

目的观察以胶原缓释重组人骨形成蛋白2(recom b inan t hum an bone m orphogenetic prote in 2,rhBM P-2)复合骨髓间充质干细胞(m arrow m esenchym a l stem ce lls,M SC s)及珊瑚构建的组织工程骨修复兔颅骨极限缺损的能力。方法新西兰大白兔40只,制备颅骨极限缺损,按植入的修复物不同随机分为5组,每组8只。Ⅰ组:自体髂骨,为阳性对照组;Ⅱ组:珊瑚,为阴性对照组;Ⅲ组:rhBM P-2+珊瑚;Ⅳ组:胶原+rhBM P-2+珊瑚;Ⅴ组:M SC s+胶原+rhBM P-2+珊瑚。将其分别植入兔颅骨极限缺损处,术后8、16周行大体观察、X线片、HE染色及M asson三色染色法观察比较骨缺损修复的情况。结果术后Ⅴ组材料与Ⅰ组修复颅骨极限缺损的效果相近,缺损区大体标本可见骨样组织充填,硬度与周边骨质相近,并与周边骨质形成明显骨融合;X线阻射程度高,16周时达80.45%±2.52%;组织学观察为板层状结构的新骨组织,空白孔隙区较少。Ⅳ组修复效果次之,Ⅲ组材料成骨能力较弱,Ⅱ组大部为半透明的纤维薄膜,缺损区界限清晰。结论胶原是rhBM P-2适宜的缓释载体,胶原及M SC s对促进复合支架材料修复骨缺损有重要意义。以M SC s+胶原+rhBM P-2+珊瑚构建的组织工程骨可成为一种良好的骨缺损修复材料。