Demineralized Bone Matrix Fibers plus Allograft Bone for Multilevel Posterolateral Spine Fusion: A Game Changer?

Introduction: While autograft bone is the gold standard for multilevel posterolateral lumbar fusion, bone substitutes and graft extenders such as allograft bone, ceramics and demineralized bone matrix (DBM) have been used to avoid the morbidity and insufficient quantity associated with harvesting autologous bone. The primary objective of this retrospective study was to determine whether, in patients with increased risk of operative nonunion related to multilevel fusion, adding DBM fibers to mineralized bone allograft resulted in better fusion than using allograft alone. The secondary objectives were to evaluate how adding DBM fibers affects functional disability, low back pain, intraoperative blood loss and the nonunion rate. Methods: This retrospective study involved a chart review of consecutive patients who underwent multilevel lumbar spinal fusion and were operated on by a single surgeon. The patients were divided into two groups: 14 patients received mineralized bone allograft (control group) and 14 patients received a combination of mineralized bone allograft and DBM (experimental group). Patients were reviewed at a mean of 16.4 ± 2.2 months after surgery at which point CT scans were analyzed to determine whether fusion had occurred;Oswestry disability index (ODI) and pain were also evaluated. Results: A mean of 5 levels [min 2, max 13] were fused in these patients. Posterolateral fusion as defined by the Lenke classification was not significantly different between groups. The experimental DBM group had a significantly better composite fusion score than the control group (P Discussion: Adding DBM fibers to allograft bone during multilevel posterolateral spinal fusion was safe and produced better composite fusion than using allograft only as an autograft extender.

Use of demineralized bone matrix in spinal fusion

Spinal fusion remains the gold-standard treatment for several pathological spine conditions. Although, autologous Iliac Crest Bone Grafting is considered the goldstandard graft choice to promote spinal fusion; however, it is associated with significant donor site morbidity and a limited graft quantity. Therefore, several bone graft alternatives have been developed, to augment arthrodesis. The purpose of this review is to present the results of clinical studies concerning the use of demineralized bone matrix(DBM), alone or as a composite graft, in the spinal fusion. A critical review of the English-language literature was conducted on Pubmed, using key word "demineralized bone matrix", "DBM", "spinal fusion", and "scoliosis". Results had been restricted to clinical studies. The majority of clinical trials demonstrate satisfactory fusion rates when DBM is employed as a graft extender or a graft enhancer.Limited number of prospective randomized controlled trials(4 studies), have been performed comparing DBM to autologous iliac crest bone graft in spine fusion. The majority of the clinical trials demonstrate comparable efficacy of DBM when it used as a graft extender in combination with autograft, but there is no clinical evidence to support its use as a standalone graft material. Additionally, high level of evidence studies are required, in order to optimize and clarify the indications of its use and the appropriate patient population that will benefit from DBM in spine arthrodesis.

Use of demineralized bone matrix in the extremities

Autologous bone graft is considered as the gold standard for all indications for bone grafting procedures but the limited availability and complications in donor site resulted in seeking other options like allografts andbone graft substitutes. Demineralized bone matrix(DBM) is an allograft product with no quantity limitation. It is an osteoconductive material with osteoinductive capabilities, which vary among different products, depending on donor characteristics and differences in processing of the bone. The purpose of the present review is to provide a critical review of the existing literature concerning the use of DBM products in various procedures in the extremities. Clinical studies describing the use of DBM alone or in combination with other grafting material are available for only a few commercial products. The Level of Evidence of these studies and the resulting Grades of Recommendation are very low. In conclusion, further clinical studies of higher quality are required in order to improve the Recommendation Grades for or against the use of DBM products in bone grafting procedures.

Effects of hypoxia on the biological behavior of MSCs seeded in demineralized bone scaffolds with different stiffness

Matrix stiffness has been demonstrated in many studies to adjust the biological behaviors of mesenchymal stem cells (MSCs). However, in the initial phase of bone restore, MSCs will encounter a hypoxic microenvironment. Studying the connection existing between the matrix stiffness and biological behavior of MSCs under hypoxic condition can better simulate the microenvironment at the prime period of bone repairment. In this work, three-dimensional (3D) decalcified bone scaffolds with diverse stiffness (high stiffness (66.06 ± 27.83) MPa, medium stiffness (26.90 ± 13.16) MPa, and low stiffness (0.67 ± 0.14) MPa) but same microstructure have been prepared by controlling decalcification time. In addition, the decellularized bone scaffold was regard as control group and its stiffness was (230.93 ± 72.65) MPa. The viability, proliferation, infiltration, and osteogenic differentiation of MSCs seeded into these 3D demineralized bone scaffolds were systematically investigated under 100 μM CoCl2-simulated hypoxic and normoxic environments. The results showed that the viability, proliferation, and extracellular matrix (ECM) secretion of MSCs had no significant difference on scaffolds with diverse stiffness but the degree of collagen deposition of MSCs gradually increased with the increase of scaffold stiffness both under normoxia and hypoxia. Compared to normoxia, the viability, proliferation, ECM secretion, vascular endothelial growth factor (VEGF) expression, and osteogenis of MSCs on the scaffolds with the same stiffness were evidently inhibited by hypoxia. Additionally, under hypoxic condition, the expression of VEGF and hypoxia inducible factor 1α(HIF-1α) in MSCs on the low stiffness scaffold was markedly increased comparing to those on other groups. In summary, we found that the low stiffness scaffold can improved the proliferation and osteoginic differentiation of MSCs under hypoxic environment, which may help to explore efficient methods for bone defect repairing.

Soft tissue swelling incidence using demineralized bone matrix in the outpatient setting

AIM To assess use of demineralized bone matrix(DBM) use in anterior cervical discectomy and fusion(ACDF) in outpatient setting.METHODS One hundred and forty-five patients with prospectively collected data undergoing single and two level ACDF with DBM packed within and anterior to polyetheretherketone(PEEK) cages. Two groups created, Group 1(75) outpatients and control Group 2(70) hospital patients. Prevertebral soft tissue swelling(PVSTS) was measured anterior to C2 and C6 on plain lateral cervical radiographs preoperatively and one week postoperatively and fusion assessed at two years. RESULTS There was no intergroup significance between preoperative and postoperative visual analogue scales(VAS)and neck disability index(NDI) scores between Group 1 and 2. Mean preoperative PVSTS in Group 1 was 4.7 ± 0.2 mm at C2 level and 11.1 ± 0.5 at C6 level compared to Group 2 mean PVSTS of 4.5 ± 0.5 mm and 12.8 ± 0.5, P = 0.172 and 0.127 respectively. There was no radiographic or clinical evidence of adverse reaction noted. In Group 1 mean postoperative PVSTS was 5.5 ± 0.4 mm at C2 and 14.9 ± 0.6 mm at C6 compared Group 2 mean PVSTS was 4.9 ± 0.3 mm at C2 and 14.8 ± 0.5 mm at C6, P = 0.212 and 0.946 respectively. No significant increase in prevertebral soft tissue space at C2 and C6 level demonstrated.CONCLUSION ACDF with adjunct DBM packed PEEK cages showed a statistical significant intragroup improvement in VAS neck pain scores and NDI scores(P = 0.001). There were no reported serious patient complications; post-operative radiographs demonstrated no significant difference in prevertebral space. We conclude that ACDF with DBMpacked PEEK cages can be safely done in an ASC with satisfactory outcomes.

保留反应性软组织联合脱矿牙本质基质应用于拔牙位点保存

背景:反应性软组织内的干细胞间充质具有促进组织再生的潜力,脱矿牙本质基质具有良好的生物相容性,可以作为位点保存术的支架材料,促进骨细胞的附着、增殖和分化。目的:影像学分析拔牙保留反应性软组织1个月后、行脱矿牙本质基质位点保存术后6个月牙槽骨高度和宽度的变化。方法:纳入38例患者共62个拔牙位点,拔除患牙保留反应性软组织1个月后应用脱矿牙本质基质行位点保存术,术前、术后即刻、术后6个月拍摄锥形束CT,分别测量近中骨高度、中央骨高度、远中骨高度、颊侧骨高度、舌侧骨高度、牙槽嵴宽度,根据拔牙后剩余牙槽窝骨壁数量分为一壁骨缺损、二壁骨缺损、三壁骨缺损、四壁骨缺损。比较位点保存术前、术后即刻、术后6个月的骨量变化。结果与结论:①在骨愈合期间无位点发生创口感染;②与位点保存术前比较,术后即刻骨高度、骨宽度明显增加(P<0.05);术后6个月骨高度增加(P<0.05),骨宽度无明显变化(P>0.05);与术后即刻比较,术后6个月骨宽度吸收了(1.253±2.896)mm(P<0.05),骨高度无明显变化(P>0.05);③位点保存术后即刻、术后6个月4种骨缺损类型的骨高度明显增加(P<0.05),骨宽度无显著变化(P>0.05);术后6个月较术前一壁骨缺损近中骨量增长最少(P<0.05),二壁骨缺损近中骨量增长最多(P<0.05);④结果表明:脱矿牙本质基质应用于位点保存术可有效预防和减缓拔牙术后的牙槽骨吸收,能够在一定程度上重建已发生吸收的牙槽骨轮廓;拔牙术后保留反应性组织应用于脱矿牙本质基质位点保存术中,可实现创口封闭,临床疗效好;脱矿牙本质基质应用于一壁、二壁、三壁、四壁牙槽窝位点保存效果相似,但总体而言,脱矿牙本质基质应用于骨壁完整的拔牙窝时位点保存效果更为优良。

脱矿牙本质基质和脱细胞牙本质基质成骨效果的对比研究

目的比较骨缺损区植入脱矿牙本质基质和脱细胞牙本质基质的成骨效果。方法制备脱矿牙本质基质和脱细胞牙本质基质。将24只SPF级SD雄性大鼠随机分为脱矿组(A组)、脱细胞组(B组)、Bio-Oss骨粉组(C组)、空白组(D组),每组6只大鼠,在麻醉条件下制备双侧股骨骨缺损。A、B、C组大鼠分别在骨缺损区植入脱矿牙本质基质、脱细胞牙本质基质、Bio-Oss骨粉,D组大鼠不植入任何材料。术后4周和8周,每组各随机处死3只大鼠。大体观察骨缺损区愈合情况,血清学检测成骨指标骨形态发生蛋白(BMP)-2及碱性磷酸酶(ALP)浓度,影像学观察骨缺损区高密度灰色区(代表骨愈合)分布情况,组织形态学观察新骨形成情况,计算新骨形成率。结果术后4周和8周,大体观察见A组成骨能力较其他组活跃,血清学检测A组BMP-2及ALP浓度均高于其他组,差异有统计学意义(P<0.05)。8周时,影像学观察可见A组骨缺损区高密度灰色区分布均匀,组织形态学观察见A组排列规则的骨基质。A组4、8周时的新骨形成率分别为28.51%±0.55%、32.57%±2.28%,均高于其他组,差异有统计学意义(P<0.05)。结论脱矿牙本质基质比脱细胞牙本质基质具有更好的成骨潜能。

陈旧颅骨的DNA检验

陈旧颅骨DNA含量低且降解严重,一直是法医DNA检验的难点之一。本文介绍了一种改善陈旧颅骨DNA检验效果的方法,在几起陈旧颅骨案件DNA检验中,从取材部位的选择、脱钙液浓缩与回收、大体系提取纯化等方面对DNA提取进行优化,成功获得常染色体和Y染色体STR多态性检验结果。结果表明:颞骨岩部可作为陈旧颅骨检验优选的取材部位,与颅骨其他部位相比成功率较高;此外,在骨粉脱钙环节,利用Amicon Ultra-1510K离心超滤管可去除脱钙液中大量的水分和离子等小分子,从而将大分子DNA截留回收,有效降低了DNA损耗量;另外,陈旧颅骨DNA质量较差,提高骨粉使用量、增加提取纯化体系也能明显提升DNA回收量。本方法提高了陈旧颅骨的DNA回收量和质量,可为后续类似陈旧骨骼、牙齿DNA检验提供借鉴。

An overview on bone protein extract as the new generation of demineralized bone matrix

Bone protein extract is regarded as the new generation of demineralized bone matrix. The aim of this paper is to describe and characterize the properties of demineralized bone matrix and its new generation product in addition to its application in animal and human studies. Bone protein extract has features of osteoconductivity, osteoinductivity and osteogenicity, which originate from its unique and precise processing. It has exhibited powerful bone formation capacity both in animal experiments and in clinical trials by providing an optimal microenvironment for osteogenesis. Furthermore, not only does it have excellent bio- compatibility, it also has good compatibility with other implant materials, helping it bridge the host and implanted materials. Bone protein extract could be a promising alternative for demineralized bone matrix as a bone graft substitute.

Development of photoreactive demineralized bone matrix 3D printing colloidal inks for bone tissue engineering

Demineralized bone matrix(DBM)has been widely used clinically for dental,craniofacial and skeletal bone repair,as an osteoinductive and osteoconductive material.3D printing(3DP)enables the creation of bone tissue engineering scaffolds with complex geometries and porosity.Photoreactive methacryloylated gelatin nanoparticles(GNP-MAs)3DP inks have been developed,which display gel-like behavior for high print fidelity and are capable of post-printing photocrosslinking for control of scaffold swelling and degradation.Here,novel DBM nanoparticles(DBM-NPs,∼400 nm)were fabricated and characterized prior to incorporation in 3DP inks.The objectives of this study were to determine how these DBM-NPs would influence the printability of composite colloidal 3DP inks,assess the impact of ultraviolet(UV)crosslinking on 3DP scaffold swelling and degradation and evaluate the osteogenic potential of DBM-NP-containing composite colloidal scaffolds.The addition of methacryloylated DBM-NPs(DBM-NP-MAs)to composite colloidal inks(100:0,95:5 and 75:25 GNP-MA:DBM-NP-MA)did not significantly impact the rheological properties associated with printability,such as viscosity and shear recovery or photocrosslinking.UV crosslinking with a UV dosage of 3 J/cm2 directly impacted the rate of 3DP scaffold swelling for all GNP-MA:DBM-NP-MA ratios with an∼40%greater increase in scaffold area and pore area in uncrosslinked versus photocrosslinked scaffolds over 21 days in phosphate-buffered saline(PBS).Likewise,degradation(hydrolytic and enzymatic)over 21 days for all DBM-NP-MA content groups was significantly decreased,∼45%less in PBS and collagenase-containing PBS,in UV-crosslinked versus uncrosslinked groups.The incorporation of DBM-NP-MAs into scaffolds decreased mass loss compared to GNP-MA-only scaffolds during collagenase degradation.An in vitro osteogenic study with bone marrow-derived mesenchymal stem cells demonstrated osteoconductive properties of 3DP scaffolds for the DBM-NP-MA contents examined.The creation of photoreactive DBM-NP-MAs and their application in 3DP provide a platform for the development of ECM-derived colloidal materials and tailored control of biochemical cue presentation with broad tissue engineering applications.

三种骨移植材料的骨诱导活性对比实验研究

[目的]通过对人工骨硫酸钙(CS)、同种异体和异种脱矿骨(DBM)3种骨移植材料异位诱导成骨效应的观察,比较其骨诱导活性优劣,为临床选择合适的骨移植材料提供参考依据。[方法]采用大鼠股部肌袋内埋植实验。选择成年斯普拉大鼠共36只,随机分成A、B2组,每组18只。A组左侧植入CS(A1),右侧植入同种异体DBM(A2);B组左侧植入异种DBM(B1),右侧不植入任何材料行空白对照(B2)。通过异位诱导成骨实验,在植入后2、4、6周取材作大体、组织形态学观察及碱性磷酸酶(ALP)和钙离子生化测定,对不同材料的骨诱导活性进行评价。[结果]术后2周,2种DBM被纤维组织包裹,可观察到DBM骨片周围间充质细胞聚集;4周时可见软骨细胞、成骨细胞形成;6周时有类似软骨基质样物质形成;ALP和钙离子含量在各时间段均高于对照组,说明2种DBM具有骨诱导活性,其结果差异具有供体依赖性。而CS降解吸收快,炎症反应轻,未见诱导成骨现象。[结论]2种DBM具有骨诱导活性,同种异体DBM较好,异种DBM次之,供体的差异性和DBM的制备可影响其在体内的骨诱导活性。CS生物相容性较好,是可供选择的骨修复填充材料。

脱钙骨基质支架构建组织工程骨的实验研究

目的 以同种异体骨脱钙骨基质(demineralizedbonematrix ,DBM )为支架材料,复合体外诱导培养的人骨髓间充质干细胞(humanmesenchymalstemcells ,hMSCs) ,构建组织工程骨并通过裸鼠皮下异位成骨实验及裸鼠皮下致瘤性实验验证其成骨效果及安全性。方法 贴壁法培养hMSCs ,体外诱导培养扩增,以1 85 7×10 6/ml的密度与DBM复合构建组织工程骨,体外培养,并在扫描电镜下观察细胞与材料复合情况,进行组织学观察。同时进行了裸鼠皮下异位成骨实验。结果 细胞与支架复合后3d ,细胞与DBM表面及孔隙可实现良好复合;复合后5d ,扫描电镜观察到细胞基质分泌旺盛,充满支架孔隙。裸鼠皮下成骨实验证明其成骨效果良好。结论 以本实验中使用的细胞培养方法扩增、诱导分化的种子细胞生物安全性好,自制的DBM具有良好的生物相容性,可为种子细胞生长提供较好的三维空间,按照标准化工艺流程制备的组织工程骨安全、有效。

骨髓基质干细胞与不同支架材料复合异位成骨能力的实验研究

目的:研究骨髓基质干细胞(bone marrow stromal cells,BMSCs)与不同支架材料复合后的异位成骨能力。方法:将体外诱导培养的成年犬骨髓基质干细胞,以1×106/cm2的密度接种到冻干骨基质(fdDBM)、磷酸三钙(TCP)、孔径分别为200μm及500μm的珊瑚羟磷灰石(CH200、CH500)等支架材料上,分别于体外培养的第4￣7天进行扫描电镜及石蜡切片HE染色,了解细胞在不同支架上的黏附及生长情况,并于1周后将大小为10mm×5mm×2mm的上述细胞支架复合物(fdDBM、TCP、CH200、CH500)分别植入裸鼠(n=8)背部皮下,每只裸鼠均植入4个实验组及1组无细胞的fdDBM空白支架对照组。9周后,取材行石蜡切片及HE染色,以IMAGER-PROPLUS软件测量每组的新生骨小梁量,并采用SAS软件包行单因素方差分析。结果:犬BMSCs与4种支架材料均黏附良好,TCP、CH200及CH5003组各样本均能观察到新骨形成,fdDBM及fdDBM空白对照组分别有75%、25%的样本有新骨形成;其中,TCP组的TBV值(28.2%±2.86%)显著高于CH200组(24.1%±4.12%)及CH500组(18.1%±4.66%)(P<0.01)。结论:BMSCs与4种材料的相容性良好。TCP与BMSCs复合后异位成骨效果显著,是很有希望的骨组织工程支架材料。

成骨细胞与生物衍生材料联合培养的实验研究

目的 探索冻干脱钙骨基质 (FDBM)作为组织工程骨支架的可行性。方法 取兔颅骨外膜的成骨细胞 ,经传代培养后作为种子细胞与 FDBM于体外联合培养 ,通过对复合物相差显微镜、光镜及扫描电镜等观察 ,了解细胞在材料中的生长情况。结果 经系统处理后的 FDBM呈现不规则的网 -孔结构 ,其孔隙直径为 10 0～40 0 μm,孔隙率为 70 %。体外复合培养 8小时 ,成骨细胞即开始贴附于 FDBM网架上 ;复合培养 7天 ,分布于支架材料上的成骨细胞迅速分化增殖 ,分泌细胞外基质并形成钙结节。结论

绵羊椎体骨质疏松性生物力学模型的快速建立

目的运用微量注射泵向椎体内灌注盐酸及椎体整体浸泡的脱钙方法,快速建立绵羊腰椎骨质疏松性生物力学模型。方法(1)设计一款可拧入椎弓根带侧孔的圆柱形灌注连接器,做为椎体内部与注射泵的桥接装置。(2)将(3±0.5)岁新鲜绵羊腰椎48个,随机分为4个处理组:A组(0 h脱钙,即空白组),B组(2 h脱钙),C组(4 h脱钙),D组(6 h脱钙)。每组12个椎体。(3)检测各组椎体脱钙前后BMD;进行生物力学实验:测试最大轴向拔出力(Fmax)和最大抗压强度及其能量吸收值。同时各组取少量骨质制成组织切片,对脱钙后绵羊腰椎骨小梁微观结构进行观察。结果B、C、D处理组的BMD均值、最大轴向拔出力均值和最大抗压强度及其能量吸收值均值都低于A组(P<0.01),且随脱钙时间的延长依次降低(P<0.01)。椎体的最大轴向拔出力及最大抗压强度与BMD存在正相关关系,亦与BMD的下降值存在负相关。切片显示:B、C、D组椎弓根处骨小梁较A组骨小梁厚度明显变薄、数量减少,间距增宽,部分骨小梁连续性中断,骨髓腔扩大。结论运用微量注射泵向椎体内灌注盐酸及整体浸泡的脱钙方法,可快速、有效、可控的建立近似于骨质疏松状态下的生物力学模型,为在真正骨质疏松状态下的生物力学研究提供参考依据。

酪蛋白磷酸多肽/无定形磷酸钙复合物与氟化钠预防正畸托槽周围的牙釉质脱矿

背景:临床上,酪蛋白磷酸多肽/无定形磷酸钙复合物与氟化钠均能有效防止釉质脱矿发生和龋坏出现。目的:观察酪蛋白磷酸多肽/无定形磷酸钙复合物与氟化钠在固定正畸矫治过程中对牙釉质脱矿的预防作用,寻求效果好的再矿化试剂。方法:将40颗已粘接好托槽的人离体牙随机分为4组,对照组表面不涂布任何物质,护牙素组表面涂布酪蛋白磷酸多肽/无定形磷酸钙复合物,多乐氟组表面涂布氟化钠,联合组表面同时涂布酪蛋白磷酸多肽/无定形磷酸钙复合物与氟化钠。将4组牙齿进行连续14 d的脱矿-再矿化实验,实验结束后扫描电镜观察牙釉质表面孔隙情况,同时测量各组实验前后的显微硬度变化值。结果与结论:对照组出现明显牙釉质脱矿现象,其他3组牙釉质脱矿现象不明显。护牙素组、多乐氟组、联合组的显微硬度变化值均低于对照组(P<0.05),护牙素组、多乐氟组、联合组间显微硬度变化值比较差异无显著性意义。说明氟化钠、酪蛋白磷酸多肽/无定形磷酸钙复合物及两者同时使用在体外实验中均可防止牙釉质脱矿,促进再矿化,但两者联用并未明显提高预防牙釉质脱矿作用。

羟基磷灰石/脱矿骨复合物增高牙槽嵴的实验研究

【目的】观察羟基磷灰石 (HA) /脱矿骨复合物骨膜下植入增高牙槽嵴的成骨反应。【方法】在犬下颌体部及下颌磨牙区无牙颌牙槽骨顶部 ,骨膜下植入羟基磷灰石 /脱矿骨复合物为实验组 ,并设单独羟基磷灰石植入为对照组。经 3周、6周、12周和 2 4周后处死动物 ,取材作大体观察、组织学观察和扫描电镜观察。【结果】实验组术后 3周即见类骨质产生 ,材料和基骨界面开始结合 ;术后 6周材料和基骨大部分结合 ;12～ 2 4周新骨增多 ,相互连接 ,充满羟基磷灰石间隙并与之结合。对照组术后 3周未见新骨形成 ;术后 6周材料与基骨始见结合 ;术后 12～ 2 4周只见新骨从界面少许形成。【结论】骨膜下植入羟基磷灰石 /脱矿骨复合材料较之单纯的羟基磷灰石植入可见较快的新骨形成 ,材料和基骨界面较早结合 。

骨形态发生蛋白4、脱钙骨基质和切断跟腱诱导的异位骨化动物模型的研究

目的:建立骨形态发生蛋白4(bone morphogenetic protein 4,BMP4)、脱钙骨基质和切断跟腱诱导的异位骨化动物模型,并初步探讨其形成机制,为异位骨化的研究奠定实验基础。方法:制备动物模型:(1)构建BMP4重组腺病毒,实验组裸鼠的一侧腓肠肌内注入50μl1×107pfu BMP4重组腺病毒液,对照组腓肠肌内注入50μl1×107pfu空病毒液。4周后行X线和组织学检查。(2)无菌条件下,股后外侧入路,将50mg脱钙骨基质植入裸鼠股后肌群内,4周后行X线和组织学检查。(3)20只小鼠于跟腱中点行跟腱切断术,10周后行X线和组织学检查。结果:X线和组织学检查显示4周后,注射BMP4重组腺病毒的动物均出现异位骨,注射空病毒组未见异位骨形成。4周后,植入脱钙骨基质的动物均出现异位骨。10周后,行跟腱切断术的动物均在跟腱部位出现异位骨。结论:BMP4、脱钙骨基质和切断跟腱可有效诱导异位骨化,结果稳定可靠。

犬脱钙骨基质复合骨髓间充质干细胞的体外培养

目的:制备犬脱钙骨基质(demineralized bone matrix,DBM),研究DBM作为骨组织工程支架材料的可行性。方法:杂种犬的股骨行脱脂、脱钙、脱非胶原蛋白、冷冻干燥、灭菌制成DBM,与骨髓间充质干细胞(mesenchymal stemcells,MSCs)复合,应用倒置相差显微镜、扫描电镜观察脱钙骨基质的结构及细胞在材料表面的生长情况。结果:犬脱钙骨基质具有三维立体网孔结构,平均孔隙直径为(254.39±88.71)μm,孔隙率约为70%。与MSCs复合培养后,细胞黏附其上,上架率高,生长状态良好,增殖迅速,并分泌大量细胞外基质。结论:DBM具有良好的生物相容性。