稀土元素应用于骨组织工程支架材料的研究现状和展望

骨缺损是骨科的常见病之一。目前, 骨缺损的治疗以自体骨、同种异体骨及人工骨移植为主, 但3种材料均有一定的局限性。骨组织工程技术的发展为骨缺损的治疗带来了新的思路。稀土元素在增强骨组织工程支架性能方面发挥积极作用。深入探讨稀土元素在骨组织工程支架方面的作用并改善其性能, 有望为骨缺损的治愈带来希望。     

抗结核骨组织工程复合体局部治疗兔脊柱结核的对比研究

目的探讨以羟基磷灰石与/β-磷酸三钙(hydroxyapatite and/β-tricalcium phosphate,HA/β-TCP)复合体材料及同种异体骨为支架材料构建的抗结核性骨组织工程复合体,评价两种不同抗结核骨组织复合体治疗兔脊柱结核的效果。方法取3月龄经造模成功后的新西兰大白兔36只,行病灶清除术,随机分为3组,每组12只,A组于骨缺损处植入利福喷丁微球-rADSCs/HA/β-TCP抗结核骨组织工程复合体,B组于骨缺损处植入利福喷丁微球-rADSCs/同种异体骨抗结核骨组织工程复合体,C组清创后未做任何处理。术后4、8、12周行影像学(DR)检查,术后第12周将实验动物处死,取标本,行大体观察、组织病理学观察骨缺损修复情况。结果大体观察发现A组骨缺损区被新生骨组织取代;B组骨缺损基本修复,周边可见大量骨组织形成;C组骨缺损处有少量骨组织形成,可见大量纤维组织覆盖。X线观察发现:4周时,A组骨缺损区可见少量骨痂形成,材料与周围骨组织紧密接触。B组骨缺损区可见骨痂形成,C组骨缺损区界限清晰,可见片状低密度影。8周时,A组骨缺损区明显缩小,材料吸收,边界稍模糊。B组骨缺损区可见片絮状高密度影,C组骨缺损区可见点状钙化影。12周时,A组骨缺损区材料基本吸收,B组骨缺损材料部分吸收,椎间隙部分融合,C组骨缺损区界线尚清,椎间隙破坏缺损。组织病理学检查发现:术后12周,A组材料吸收明显,可见大量纤维骨痂组织生成骨组织。B组可见部分同种异体骨残留,周边可见大量纤维骨痂组织生成骨组织。C组可见大量纤维组织形成。结论利福喷丁微球-rADSCs/HA/β-TCP构建的抗结核骨组织工程复合体具有良好的生物相容性,能够有效填充兔腰椎结核病灶清除术后的骨缺损。     

组织工程化新生骨组织的构建方式及临床应用

临床上由于创伤、肿瘤等原因导致的骨缺损发病率较高 ,传统的治疗方法中自体或异体骨移植存在着骨源有限和排斥反应等问题 ,预后不理想。二十世纪八十年代骨组织工程学的兴起和发展为骨缺损的修复展现了美好的前景 ,即应用细胞生物学和工程学的原理 ,研究开发出修复、保持或改善骨组织功能的生物替代物 ,充填骨缺损 ,逐渐与宿主骨愈合并被自身骨组织替换 ,利用组织工程学方法制备的骨替代物称为组织工程化骨。种子细胞、基质材料、活性因子是骨组织工程学的三个组成部分 ,根据不同的组合 ,组织工程化骨的构建就有三种方式 ,也是三个发展的方…     

周围神经及骨代谢与组织工程骨的构建

创伤、感染、肿瘤等疾患常常造成骨组织缺损,引起功能障碍。其临床治疗可采用自体骨移植、同种异体骨移植、异种骨移植等方法,但这些方法由于供源有限、免疫排斥、感染等原因,故均有其局限性。骨组织工程研究的最终目的是将骨组织工程技术及产品应用于临床,修复患者骨缺损。植物神经纤维随支配骨的脊神经和骨滋养动脉进入骨组织,通过分泌包括神经肽在内的多种多肽类生物活性物质影响骨的营养和代谢状态以及血管的发生和长入。我们在总结血管、周围神经系统和各种肽对骨代谢的影响后,为寻求一种生理环境下更接近体内自然状态的组织工程骨愈合方式,提出了组织工程骨的神经化构建观点,对组织工程骨神经化构建的方法、现状、前景与研究思路进行了叙述。     

骨缺损修复生物材料的研究进展

骨移植被广泛应用于临床以修复骨缺损,目前全球对骨移植的需求非常高,每年至少进行220万次植骨手术。由于创伤、癌症、感染、关节炎等疾病引起的骨缺损不断增多,临床治疗中对骨移植物的需求也持续上升。自体骨移植和同种异体骨植骨是临床治疗骨缺损的常用方法,但慢性炎症、疾病传播和免疫排斥反应的发生阻碍了其发展。在临床迫切需求的驱动下,骨组织工程领域应运而生,组织工程技术修复骨缺损被认为是一种理想方法。骨再生生物材料是一类可以支持骨组织在缺损部位的再生过程,同时在原位降解后能够被新生成的骨组织取代的组织工程支架。近年来,水凝胶、纳米纤维支架、3D打印复合支架等多种形式的骨修复材料已取得重要进展,本文围绕骨再生工程领域研究现状,重点介绍了几种典型的骨缺损修复材料的理化性质和应用前景,为研发新一代组织工程支架用于骨缺损修复的治疗提供新思路。     

多孔磷酸三钙与自体红骨髓复合移植修复骨缺损的临床应用

为观察多孔磷酸三钙（ｔｒｉｃａｌｃｉｕｍｐｈｏｓｐｈａｔｅ，ＴＣＰ）与自体红骨髓（ｂｏｎｅ－ｍａｒｒｏｗ，ＢＭ）复合移植修复骨缺损的临床应用效果，应用ＴＣＰ－ＢＭ复合移植，修复骨缺损２１例，其中肿瘤性骨缺损１７例，陈旧性骨折骨缺损４例。术后定期拍摄Ｘ线片复查。术后６周，植入人工骨与周围骨组织界面间已有明显新骨形成；术后３个月，植入材料与周围骨组织愈合成一体。随访１～３年，结果显示植入材料的成骨作用明显，效果满意。ＴＣＰ－ＢＭ具有骨传导和骨诱导双重成骨作用，能促进新骨形成和加快骨缺损修复，是治疗骨缺损较理想的方法之一     

组织工程化新生骨组织的构建方式及临床应用

临床上由于创伤、肿瘤等原因导致的骨缺损发病率较高,传统的治疗方法中自体或异体骨移植存在着骨源有限和排斥反应等问题,预后不理想。二十世纪八十年代骨组织工程学的兴起和发展为骨缺损的修复展现了美好的前景,即应用细胞生物学和工程学的原理,研究开发出修复、保持或改善骨组织功能的生物替代物,充填骨缺损,逐渐与宿主骨愈合并被自身骨组织替换,利用组织工程学方法制备的骨替代物称为组织工程化骨。种子细胞、基质材料、活性因子是骨组织工程学的三个组成部分,根据不同的组合,组织工程化骨的构建就有三种方式,也是三个发展的方向:基质材料与种子细胞、基质材料与活性因子、基质材料加种子细胞与活性因子。随着研究的深入,又出现了血管化的复合组织工程化骨。骨组织工程的临床研究尚处于起步阶段,临床应用和有关文献报道较少。根据骨构建的方式和临床应用综述如下。     

兔骨髓基质细胞促进血管生成和成骨作用

目的了解骨髓基质细胞(BMSCs)对珊瑚人工骨血管生成和成骨作用的影响。方法从兔的骨髓中分离BMSCs进行体外培养扩增后,载入珊瑚人工骨,植入新西兰白兔桡骨干中段15 mm的骨缺损内,与未植入任何填充材料和仅植入珊瑚人工骨的实验动物相比较,使用放射学、微量CT和组织形态学等方法对骨缺损内新生血管和骨组织进行定量分析。结果未植入填充材料的骨缺损全部形成典型的骨折不愈合表现;植入珊瑚骨后,骨缺损内的新骨形成增加但新生血管无明显改变,术后16周无一例完全愈合;植入BMSCs和珊瑚人工骨复合物的骨缺损内新生血管和骨组织均明显增多,术后16周2/3的骨缺损完全愈合。结论BMSCs可促进血管生成和对人工骨材料的爬行替代作用。     

组织工程用山羊胫骨骨缺损模型的制备

目的 :制备骨组织工程用中国青山羊胫骨骨缺损模型。方法 :中国青山羊 9只随机分 3组制备单侧胫骨 2 0mm的骨膜与骨缺损 ,钢板内固定 ,术后放射性同位素、放射学检查、组织学方法评价骨缺损自行修复情况。结果 :术后同位素ROI记数 (p >0 .0 5)与摄取比值T/NT(p >0 .0 5)显示无骨代谢 ,所有动物骨缺损处X线片Lane评分均为 0分 ,组织学显示无骨组织长入。结论 :山羊胫骨2 0mm缺损模型不能自主成骨 ,符合骨组织工程实验的要求。     

人脂肪干细胞在骨组织工程中应用的研究进展

大面积骨缺损的修复一直是临床面临的难题。近年来,干细胞和骨组织工程研究的不断深人,为临床骨缺损的修复提供了新的思路。脂肪干细胞（Adipose—derivedstemcell,ADSC）由于来源丰富且容易获取,体内、外实验均证实其能分化形成骨样组织,已成为骨组织工程的重要的种子细胞来源。本文就hADSC的免疫表型、体内成骨、成骨分化的调控及骨形态发生蛋白2（Bonemorphogenetic protein-2,BMP2）对hADSC成骨分化的影响进行综述。     

骨组织工程支架材料合成技术的进展

组织工程骨是由人工支架材料体外复合扩增的成骨细胞或其前体细胞及生物活性分子构成,高孔隙支架材料在细胞黏附、增殖和新骨组织形成过程中起到最重要的作用。过去的十年,产生和发展了许多合成生物可降解支架材料的技术,骨组织工程研究取得了可喜的成绩。本文主要是回顾这些技术在支架材料的设计、制做工艺,以及各种技术不同参数对支架材料(孔隙率、孔径大小、孔隙连通率等)的影响,阐述不同技术的发展过程的优缺点。     

Tissue engineering solutions for cleft palates.

PURPOSE: Clefts of the lip and palate are the most prevalent congenital craniofacial birth defect in humans. The developing field of tissue engineering is considered for the management of clefts of the lip and palate. MATERIALS AND METHODS: A review of the literature was carried out by using electronic databases (such as PubMed and ISI Web of Science) to search topics including "cleft palate," "tissue engineering," "bone engineering," "palate engineering," and "alveolar bone grafting." To reflect current practice and research, these searches were limited primarily to articles published after the year 2000. RESULTS: Current approaches for the treatment of clefts of the lip and palate include surgery and bone grafts; however, there are limitations associated with these therapies. Tissue engineering strategies, particularly alveolar bone engineering and soft tissue engineering, may provide clinicians with new alternatives. The application of these emerging technologies to a pediatric population must be well considered. CONCLUSIONS: A tissue engineering approach may be a useful alternative for the treatment of cleft palates as it mitigates the concerns of donor site morbidity as well as provides additional options including scaffold implantation and growth factor delivery.     

Effects of the combination of low-level laser therapy and anionic polymer membranes on bone repair

Lasers in Medical Science - In view of the limitations of bone reconstruction surgeries using autologous grafts as a gold standard, tissue engineering is emerging as an alternative, which permits...     

Biomaterials as Scaffold for Bone Tissue Engineering

Abstract Almost 20 years after the invention of tissue engineering, autogenous bone grafting has remained the favored strategy for the treatment of bone defects. As an alternative, a vast variety of bone substitutes has been developed and is available for clinical use. The ongoing search for bone substitutes, however, reflects the limitations imposed to both autogenous and allogenous bone grafts as well as to bone substitute materials. The concept of tissue engineering holds great promise for the future treatment of osseous defects. Research in this interdisciplinary field is carried out to find a way of producing biologic substitutes as functional tissue replacement. For this, functionally active cells are applied on supporting scaffolds under controlled stimulation with growth factors. Scaffolds are temporary matrices for bone growth and provide a specific environment and architecture for tissue development. Ideally, scaffolds favor cellular attachment, growth and differentiation in vitro and in vivo. Especially ceramics and biodegradable polymers are widely used and have been tested in various animal studies. Yet, to allow for precise production of specific custom-made scaffolds, rapid prototyping (RP) techniques have recently drawn a lot of attention. Using these methods scaffolds with a predefined, well-controlled internal and external architecture mimicking the structure of natural bone can be generated. Although biocompatibility of the materials used in the process and the structural resolution that can be technically achieved so far limit the range of use, rapid manufacturing techniques do offer great opportunities to generate suitable scaffolds for bone tissue engineering in the near future.     

骨组织工程学种子细胞研究进展

骨组织工程是目前组织工程学中最具有前途和临床应用可行性的研究领域之一,种子细胞是组织工程骨构建和应用研究中的首要环节和基本要素,成骨细胞是骨组织工程的种子细胞。近年来对于成骨细胞来源的选择、干细胞向成骨细胞诱导分化的调节以及成骨细胞的体外扩增都进行了深入的研究。本文结合国内外研究成果,对骨组织工程学种子细胞的研究现状进行回顾,并对其研究前景作一展望。     

Osteogenesis of Adipose-Derived Stem Cells

Current treatment options for skeletal repair, including immobilization, rigid fixation, alloplastic materials and bone grafts, have significant limitations. Bone tissue engineering offers a promising method for the repair of bone deficieny caused by fractures, bone loss and tumors. The use of adipose derived stem cells (ASCs) has received attention because of the self-renewal ability, high proliferative capacity and potential of osteogenic differentiation in vitro and in vivo studies of bone regeneration. Although cell therapies using ASCs are widely promising in various clinical fields, no large human clinical trials exist for bone tissue engineering. The aim of this review is to introduce how they are harvested, examine the characterization of ASCs, to review the mechanisms of osteogenic differentiation, to analyze the effect of mechanical and chemical stimuli on ASC osteodifferentiation, to summarize the current knowledge about usage of ASC in vivo studies and clinical trials, and finally to conclude with a general summary of the field and comments on its future direction.     

Multi-functional osteoclasts in matrix-based tissue engineering bone

The repair of bone defects, especially for the large segment of bone defects, has always been an urgent problem in orthopedic clinic and attracted researchers’ attention. Nowadays, the application of tissue engineering bone in the repair of bone defects has become the research hotspot. With the rapid development of tissue engineering, the novel and functional scaffold materials for bone repair have emerged. In this review, we have summarized the multi-functional roles of osteoclasts in bone remodeling. The development of matrix-based tissue engineering bone has laid a theoretical foundation for further investigation about the novel bone regeneration materials which could perform high bioactivity. From the point of view on preserving pre-osteoclasts and targeting mature osteoclasts, this review introduced the novel matrix-based tissue engineering bone based on osteoclasts in the field of bone tissue engineering, which provides a potential direction for the development of novel scaffold materials for the treatment of bone defects.     

Injectable hydrogels for cartilage and bone tissue engineering

Tissue engineering has become a promising strategy for repairing damaged cartilage and bone tissue. Among the scaffolds for tissue-engineering applications, injectable hydrogels have demonstrated great potential for use as three-dimensional cell culture scaffolds in cartilage and bone tissue engineering, owing to their high water content, similarity to the natural extracellular matrix(ECM), porous framework for cell transplantation and proliferation, minimal invasive properties, and ability to match irregular defects. In this review, we describe the selection of appropriate biomaterials and fabrication methods to prepare novel injectable hydrogels for cartilage and bone tissue engineering. In addition, the biology of cartilage and the bony ECM is also summarized. Finally, future perspectives for injectable hydrogels in cartilage and bone tissue engineering are discussed.     

Human shaped thumb bone tissue engineered by hydrogel-beta-tricalciumphosphate/poly-epsilon-caprolactone scaffolds and magnetically sorted stem cells

Traumatic amputation of a thumb with bone loss leaves a patient in severe disability. Reconstructive procedures are restricted by limited shape and have the disadvantage of severe donor-site morbidity. To overcome these limitations, we used a tissue engineering approach to create a distal thumb bone phalanx, combining magnetically sorted 133+ human mesenchymal stem cells (hMSCs) suspended in successful tested hydrogels for bone formation and porous 3-dimensionally printed scaffolds (3DP) in the shape of a distal thumb bone phalanx. Collagen I and fibrin glue hydrogels with suspended hMSCs were first histologically evaluated in vitro for bone formation after 6 weeks.Then 3DP scaffolds, made from a mix of osteoinductive and -conductive beta-tricalciumphosphate (beta-TCP) and poly-epsilon-caprolactone (PCL), with hydrogels and suspended hMSCs, were implanted into nude mice subcutaneously for 15 weeks. Histologic evaluation, high-resolution volumetric CT (VCT) scanning, and biomechanical testing confirmed formation of bonelike tissue. Both hydrogels with CD 133+ hMSCs on 3DP scaffolds supported bone formation. Collagen I resulted in radiologically better bone formation. Bone tissue can be successfully tissue engineered with CD 133+ hMSCs, collagen I hydrogels, and porous 3DP beta-TCP/PCL scaffolds.     

组织工程骨的研究

目的 综述组织工程骨研究中的种子细胞、支架材料和组织构建的近期进展。方法 广泛查阅近期有关组织工程骨的研究文献，着重在研究和探索人骨髓细胞体外培养、乌贼骨改性和骨组织构建动物实验。结果 人骨髓细胞培养中诱导、分化出成骨细胞；首次将乌贼骨改性为乌贼骨羟基磷灰石；构建出成骨细胞／CHA500R、成骨细胞／乌贼骨羟基磷灰石、成骨细胞／聚羟基丁酸酯等组织工程骨。结论 骨髓来源的成骨细胞和上述支架材料构建的组织工程骨有望在临床上应用。