猪骨形态发生蛋白体外诱导小鼠肌组织成骨的实验研究

这项研究借助体外培养技术，动态观察猪骨形态发生蛋白对小鼠骨骼肌增殖分化的作用。实验结果表明，猪骨形态发生蛋白可体外诱导新生鼠骨骼成骨，但对成年鼠骨骼肌无诱导作用；ＲＰＭＩ－１６４０培养基可使软骨细胞表型得以充分表达；建立的实验模型对鉴定骨形态发生蛋白活性有一定实用价值。此外，在体外诱导肌组织成骨实验过程中还观察到其它学者未曾报道过的软骨溶解期。     

超临界液体精密分离装置的自动升压系统

由MCS-51单片微机、压力传感器、高精度A/D转换器和调节阀组成的闭环控制系统用于重油超临界精密分离装置.进行自动线性升压.采用伺服电机带动的针形阀代替小型通用调节阀进行压力调节.实验证明.此控制系统升压平稳。线性度好.通过拨码开关予置参数.使操作简便,运行安全可靠.     

骨髓基质细胞与成骨

自体红骨髓异位移植后，骨髓基质细胞可增殖并分化成骨，动物实验和临床实践提示，自体红骨髓复合模骨有助于骨折愈合。     

成骨细胞诱导骨髓基质细胞体外成骨的初步研究

目的:探讨在不使用细胞因子或化学药物的情况下,成骨细胞(Osteoblast,OB)与骨髓基质细胞(Bone Marrow Stromal Cells,BMSCs)混合培养时,成骨细胞提供的成骨微环境能否在体外诱导BMSCs向成骨细胞分化,并复合支架形成成熟的骨组织.研究成骨细胞诱导BMSCs有效成骨的最小比值(指成骨细胞与骨髓基质干细胞数量的比值).方法:SY别培养SD乳鼠的成骨细胞与SD大鼠的BMSCs,将成骨细胞和BMSCs以1:9、2:8、3:7、1:0的不同比例进行混合培养,通过测定第3、6、9天培养液上清中的碱性磷酸酶(ALP)的含量,研究成骨细胞促BMSCs有效成骨的最小比值.将两种细胞以该最小浓度比混匀接种于涂附Ⅰ型胶原壳聚糖材料支架上(直径9 mm,高3mm)作为混合培养组,相同终浓度的单纯成骨细胞和单纯BMSCs分别接种于相同支架作为阳性对照及阴性对照.另设置低比值成骨细胞对照组(仅含有共培养组中相同的成骨细胞数,但不含有共培养组中的BMSCs).全部标本均于体外培养8周后取材,通过大体观察、组织学及免疫组织化学等相关检测对新生骨进行评价.结果:成骨细胞和BMSCs以3:7的比例进行混合培养时已可实现有效成骨.3:7比例的混合培养组及阳性对照组(成骨细胞组)体外培养8周后大体观察和苏木素-伊红染色(HE)、ALP染色基本相同,均表达骨特异性细胞外基质Ⅰ型胶原,形成了较成熟的骨组织.阴性对照组(单纯BMSCs组)和低比值成骨细胞组,原细胞支架复合物变小、变形.低比值成骨细胞组在局部形成了少量的骨组织,阴性对照组(单纯BMSCs组)未能发现骨样组织形成.结论:在不使用细胞因子或化学药物的情况下,成骨细胞提供的成骨微环境能够在体外诱导BMSCs向成骨细胞分化并形成成熟的骨组织.混合细胞中成骨细胞与BMSCs的比例为3:7时是有效成骨的最小比值.     

Study on vertical mandibular distraction osteogenesis using magnesium alloy on canine

The bone formation feasibility by a novel magnesium alloy device was evaluated using a canine vertical mandibular distraction osteogenesis(DO) model. Osteotomies were performed in the area where last 3 star’s teeth of left mandibular were pulled out before 3 months. Both AZ31 magnesium alloy(n ? 6) and 316 L stainless steel(n ? 6) distraction devices were implanted. The distraction osteogenesis was carried out with a latency of 5 days after mandibular osteotomy. Distraction proceeded at a rate of 0.3 mm/8 h for 7 days and followed by 4 weeks of consolidations. The evaluations were conducted by scanning electron microscopy(SEM) and histological examinations. There were osteoblasts and trabecular bones formations manifestly in both groups. There was no significant difference in the bone mineral density between the two groups. The surface of the magnesium alloy was much more cracked and uneven, resulting from the surface pitting corrosion. The crew nails were closely combined with the surrounding bone tissue. AZ31 magnesium alloy exhibited a certain degradation rate in mandibular and did not post a negative effect on the kidney and liver. The observations in magnesium alloys group is consistent with the stainless steel group.     

电磁场促进成骨细胞体外骨发生钙离子调节机制

通过观察电磁场刺激对体外培养成骨细胞骨生成过程的作用，为临床骨伤病的治疗提供理论依据和技术方法．用体外培养兔胫骨膜成骨细胞，实验组置于２Ｈｚ，１Ａ·ｍ－１的梯形脉冲电磁场中，对照组无电磁场刺激，观察成骨细胞的增殖速度和分泌功能的差异，测量细胞内游离钙离子含量水平．结果：成骨细胞在ＤＭＥＭ＋１０％小牛血清培养基中生长良好，体外培养８ｄ可融合成一层，然后重叠生长，形成岛状骨结节，结节中部成骨细胞随着钙盐沉积坏死，少量成骨细胞向骨细胞转化，实验组成骨细胞分化生长速度明显加快．结论：体外培养成骨细胞在适宜的环境中，以膜内成骨的方式生成骨结节，这一过程可被电磁场刺激加快速度．电磁场刺激促进成骨细胞生长分化的机制与调节细胞内游离钙离子代谢有关．     

Osseointegration of hollow porous titanium prostheses loaded with cancellous bone matrix in rabbits

This study aimed to observe the osseointegration of hollow porous titanium prostheses (HPTP) loaded with cancellous bone matrix (CBM) in rabbits using histological and biomechanical perspectives.Experimental samples were implanted into the lateral femoral condyles of 66 New Zealand rabbits,allocated into the following groups:non-porous prosthesis group (Group A,n=22);HPTP group (Group B,n=22);HPTP+CBM group (Group C,n=22).The rabbits were sacrificed at 3,8 and 12 weeks,postoperatively.X-ray analyses,microscopy techniques and morphological measurement software and mechanical tests were used for evaluation.At each time point,the tissues surrounding the implants were similar in all of the groups,with bony in-growth into the 2-mm round holes observed for the defects in Groups B and C.However,the internal bone formation was significantly better in Group C than in Group B at different time points (P<0.01).Biomechanically,the pull-out forces were significantly greater in Groups B and C than in Group A (P<0.01),with no difference between Groups B and C (P>0.05).These results suggest that bone can grow into the cavities of HPTP to achieve more stable locking fixation,and those osteogenic materials,such as CBM,can enhance osteogenesis to achieve better osseointegration between the implant and the host bone.     

一氧化氮供体在牵张成骨中对骨形成速率的影响

目的探讨外源性一氧化氮供体(硝酸甘油悬浊液)对兔牵张成骨过程中骨形成速率的影响.方法日本大耳白兔60只,随机分为假手术组(SO组)、手术组(DO组)和手术给药组(NG组),每组20只.各实验组兔子分别于牵张术后1 d、1周、2周、4周、6周处死,每个时点处死4只.处死后的兔游离下颌骨行骨密度测量和钙含量测定,利用SPSS 19.0统计软件分析各组骨密度和钙含量的差异,并进行相关性分析,建立回归方程.结果在牵张术后1 d,DO组与NG组骨密度比较差异无统计学意义(P0.05),其余各组比较差异具有统计学意义(P0.05);牵张术后1周、2周、4周时,各组间比较差异均具有统计学意义(P0.05);牵张术后6周,各组间比较差异无统计学意义(P0.05).钙含量变化与骨密度变化整体趋势相同,牵张术后1 d时,DO组与NG组比较差异具有统计学意义(P0.05).骨密度与钙含量呈正相关(r=0.869,P0.01),建立回归方程:Y钙含量=-1233.97+3 794.986X骨密度-4 122.103X3骨密度.结论外源性NO供体可以加快牵张成骨新骨的形成速率,缩短手术周期,可根据回顾方程骨密度的变化趋势来推测钙含量的变化.     

纳米氧化铈颗粒对骨髓基质细胞成骨分化和成脂分化的影响

以原代骨髓基质细胞(BMSCs)为模型,在细胞水平上,研究50nm氧化铈颗粒对BMSCs的活性、成骨分化和成脂分化的影响.结果表明,氧化铈颗粒促进BMSCs的活性,并呈现很好的剂量及时间依赖性,但其对BMSCs的碱性磷酸酶(ALP)活性、胶原的合成、矿化结节的形成以及成脂分化的影响是复杂的,作用浓度和时间是影响其分化的关键因素.这些实验结果为阐明纳米氧化铈的生物学效应机理及其在生物医学领域的研究应用提供科学依据.