Constructing tissue engineered trachea-like cartilage graft in vitro by using bone marrow stromal cells sheet and PLGA internal support: experimental study in bioreactor / 中华整形外科杂志

<p><b>OBJECTIVE</b>To explore the feasibility of constructing tissue engineered trachea-like cartilage graft in vitro by using bone marrow stromal cells (BMSCs) sheet and PLGA internal support.</p><p><b>METHODS</b>Rabbit BMSCs were expanded and induced by transforming growth factor-1 to improve chondrocyte phenotype of BMSCs. BMSCs sheets were obtained by continuous culture and wrapped the PGLA scaffold in the shape of cylinder. The constructs were incubated in spinner flask for 8 weeks and cartilage formation was investigated by gross inspection, histology, glycosaminoglycan and mechanical strength content.</p><p><b>RESULTS</b>After in vitro culture, cartilage like tissue in cylindrical shape had been regenerated successfully. Stiff, shiny, pearly opalescence tissues were observed. Histological analysis showed engineered trachea cartilage consisted of evenly spaced lacunae embedded in matrix, cells stationed in the lacunae could be noticed clearly. Safranin-O staining on the sections showed homogenous and positive red staining, which demonstrated that the engineered tissue was rich in proteoglycans.</p><p><b>CONCLUSIONS</b>Based on the cell sheet and internal support strategy, trachea-like cartilage in cylindrical shape could be successfully fabricated which provided a highly effective cartilage graft substitute and could be useful in many situations of trachea-cartilage loss encountered in clinical practice.</p>

The preparation of series of the controllable degradation coral-hydroxyapatite (SCHA-200R) and the on its application as the scaffold in bone tissue-engineering / 中华整形外科杂志

<p><b>OBJECTIVE</b>Fabricate series of the controllable degradation coral-hydroxyapatite.</p><p><b>METHODS</b>The natural coral undergo a chemical reaction with (NH4)2 HPO4 at high temperature and pressure for different time-lengths. After getting the products, the components and the special structures were analyzed. Observe the biologic degradation of the reaction products and analyze the metal elements and their contents. Haemolysis tests, cytotoxity tests and bone compatibility tests were performed to assess the biocompatibility of the products.</p><p><b>RESULTS</b>When hydrothermal reactions happened under different conditions, the different gradients of CaCO3/hydroxyapatite materials were produced. These types of materials kept the characteristic of interconnected micro-porous network structures. A thin layer of compact material can be seen on the surface of its trabecula ultra-micro structure. The SCHA-200R has a good biocompatibility.</p><p><b>CONCLUSIONS</b>Gradient HA (SCHA-200R) materials can be formed by adjusting the same temperature, same pressure and different time-length of the reaction. This kind of gradient material keeps the quality of micro-porous network structures. The SCHA-200R is a potential candidate scaffold for bone tissue engineering.</p>

Repair of peripheral nerve defect by a scroll of amnion derivative compound with cultured autogenous Schwann cell in a rat model / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To test a nerve bridge substitute for peripheral nerve repair by tissue-engineering approach.</p><p><b>METHODS</b>An artificial nerve fabricated with a scroll of amnion derivative (ZQ membrane) and cultured autogenous Schwann cell was sutured to bridge sciatic nerve defect of 2.5 cm in length in rats. The specimens were assessed with tracking study, histology, electrophysiological technique, NF200, and synaptophysin-38 (SYP) immuno histochemical staining 3 months postoperatively.</p><p><b>RESULTS</b>The regenerated nerve sprouted 3 months after the operation. The regenerated nerve fibers were plentiful and could grow into the recipient nerve and target muscle's motor end plate (MEP) areas to reinnervate target muscle, and reconstruct function of nerve-muscle junction. Functional recovery could reach to 40%-60% of normal control. Nerve-muscle conduction velocity (N-MCV) arrived at 21.77 +/- 1.15 m/s.</p><p><b>CONCLUSIONS</b>A tissue engineering material fabricated with a scroll of ZQ membrane and cultured autologous Schwann cell may be a useful substitute for nerve repair.</p>

Reconstruction of caprine mandibular segmental defect by tissue engineered bone reinforced by titanium reticulum / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To investigate the feasibility of using natural poritos as scaffolds in bone tissue engineering (TE) and repair of caprine mandibular segmental defect with titanium reticulum reinforced.</p><p><b>METHODS</b>Natural poritos with a pore of 190-230 microm in size and porosity of about 50percent-65percent was molded into the shape of granules 5 mm x 5 mm x 5 mm in size. Expanded autologous caprine marrow mesenchymal stem cells were induced by recombinant human morphogenetic protein-2 (rhBMP2) to improve osteoblastic phenotype. Then marrow derived osteoblasts were seeded into poritos in density of 4 x 10(7)/ml and incubated in vitro for 48 hours prior to implantation. Then osteoblastic cells/poritos complexes were implanted into mandibular defect and the defect was reinforced by titanium reticulum. Implantation of poritos alone acted as the control. Bone regeneration was assessed 4, 8, 16 weeks after implantation using roentgenographic analysis and histological observation was done after 16 weeks.</p><p><b>RESULTS</b>New bone could be observed histologically on the surface and in the pores of natural coral in all specimens in the cell-seeding group, whereas in the control group there was no evidence of osteogenesis process in the center of the construction. The results showed that new bone grafts were successfully restored 16 weeks after implantation.</p><p><b>CONCLUSIONS</b>This study suggests the feasibility of using porous coral as scaffold material transplanted with marrow derived osteoblasts by TE method. By means of titanium reticulum reinforcement, mandibular defect could be successfully restored. It shows the potentiality of using this method for the reconstruction of bone defect in clinic.</p>

Surgical orthodontic technique for the treatment of maxillofacial deformities and dysfunction of occlusion after maxillofacial fractures / 中华整形外科杂志

<p><b>OBJECTIVE</b>To evaluate a new technique to treat severe maxillofacial deformity and dysfunction of occlusion after the maxillofacial fractures.</p><p><b>METHODS</b>Thirty-four consecutive patients, with delayed maxillofacial deformities and dysfunction of occlusion after the maxillofacial fractures, were treated by the use of x-ray cephalometric analysis, model surgery, open reduction and rigid internal fixation.</p><p><b>RESULTS</b>Thirty-three patients were successfully corrected the maxillofacial deformities, facilitated normal occlusal relationship. Only one patient with severe damage of the brain was presented a mild occlusion dysfunction one year after the operation.</p><p><b>CONCLUSIONS</b>The above-mentioned technique may be a viable and effective option for the management of the deformities of the face and dentition after the maxillofacial fractures.</p>

A study of injectable autogenous tissue-engineered bone / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the utilization of carrier for delivering osteoblasts and creating autogenous bone tissue in ectopic site of animal via injection.</p><p><b>METHODS</b>Bone marrow cells harvested from iliac bone of New Zealand rabbits were induced to differentiate into marrow stromal osteoblasts. The osteoblasts were mixed with 1.5% alginate sodium solution to generate osteoblasts/alginate composites with final cellular density of 4 x 10(9)/L. Calcium chloride was used as cross-linking agent to gel aqueous alginate solution. The marrow stromal osteoblasts/alginate composites were injected into the dorsal subcutaneous tissue of rabbits with autogenous cells transplantation. The samples were examined with X-ray and histological analysis.</p><p><b>RESULTS</b>Four, eight and twelve weeks after injection, the hard knobbles were easily palpated under the dorsal skin of animals. On X-ray photograph the samples showed calcified image with more density than surrounding soft tissue, new bone formation was observed in the osteoblasts/alginate composites in histological analysis. The osteogenesis was in association with regenerated hematopoietic bone marrow.</p><p><b>CONCLUSIONS</b>These results demonstrate that new bone tissue could be created through the injection of alginate sodium treated with autogenous marrow stromal osteoblasts.</p>