OBJECTIVETo study orientation remodeling without stress in bone harvest chamber.

METHODSThe bone harvest chamber (BHC) methodology is adopted in this study. Five female Japanese white rabbits were allowed unrestricted activity. The bone harvest chamber was a cylindrical Ti implant body with a transverse 1 mm wide canal for bone ingrowths. Retrieval of the contents of the canal was allowed with minimal disturbance to the surrounding bone or outer cylinder. After bone harvest chambers were implanted into the tibia of rabbits for 8 weeks, the chambers were considered to be osseointegrated with the bone. After harvested, the tissue were fixed and decalcified, then embedded in paraffin. Each rabbit was put into surgical operation 4 times for 4 stages: vacant for the first time; the tissue were cut into longitudinal sections at the second and third stages; harvesting tissues were cut into transverse sections at the fourth stage. Directional analysis: the standard deviation of the orientation of cell nucleus in each section was used as statistics, the difference between longitudinal section and transverse section were analyzed.

RESULTSOf the tissue into bone harvest chamber, directionality of cells arranged was more significantly on longitudinal section than on transverse section and there was statistical ignificecne.

CONCLUSIONUnder the no-stress circumstance of BHC bone remodeling showed directivity. Stress is not the direct leading signal about bone reconstitution. The structure of BHC might be related to orientation remodeling, which suggests that the relationship between orientation and stress is mediated by blood vessel. The effect of stress may be to affect vessel distributing in some orietation.

Animals ; Biomechanical Phenomena ; Cell Culture Techniques ; instrumentation ; methods ; Cells, Cultured ; Female ; Osteocytes ; chemistry ; cytology ; Rabbits ; Tibia ; chemistry ; cytology

We hypothesized that the formation and differentialtion of osteoclasts are accelerated and the potential of bone resorption is increased in the hemiplegic bone marrow in the early stage of stroke. We randomly divided white female Sprague-Dawley (SD) rats (n = 30) into two groups, stroke (n = 15) and sham group (n = 15). On the 7th day after stroke, after cutting away the epiphyses of the femurs and tibias, diaphyseal channels were flushed using alpha-minimum essential medium (alpha-MEM) and bone marrow cells were collected. Bone marrow stem cells, which were extracted from the femur and tibia, were cultured on the 7th day after middle cerebral artery occlusion. We then estimated the ratio of non-adherent cells to total bone marrow cells that included osteoclast precursor cells. After culturing these cells separately, cells that tested positive on the tartrate resistant acid phosphatase (TRAP) were counted and bone resorption was evaluated by using the OAAS(TM) plate. In comparison to the control group, the stroke group showed a higher increase of non-adherent cells in the hemiplegic side bone marrow. In addition, after the primary culture, the stroke group showed an increased number of TRAP positive cells and a higher degree of bone resorption estimated by OAAS(TM) plate. As a result, osteoclastogenesis and osteoclast differentiation are accelerated and the potential of bone resorption is increased in the hemiplegic bone marrow and these changes are detected as early as within the first week after middle cerebral artery occlusion in SD rats.
Animals ; Bone Marrow Cells/cytology/drug effects ; Bone Resorption/*physiopathology ; Cell Differentiation ; Cell Separation ; Cells, Cultured ; Female ; Femur/cytology ; Osteoclasts/cytology ; Rats ; Rats, Sprague-Dawley ; Stem Cells/cytology/metabolism ; Stroke/*metabolism/pathology ; Tartrates/pharmacology ; Tibia/cytology

OBJECTIVETo explore the possibility of expression of exogenous gene in transduced bone marrow derived stromal cells (BMSCs).

METHODSThe marker gene, pbLacZ, was transferred into cultured BMSCs and the expression of transduced gene by X-gal staining was examined. Then plasmid pcDNA3-rhBMP7 was delivered to cultured BMSCs. Through immunohistochemical staining and RT-PCR assay, the expression of rhBMP7 gene was detected.

RESULTSThe exogenous gene could be expressed efficiently in transduced BMSCs.

CONCLUSIONThe present study provided a theoretical basis to gene therapy on the problems of bone and cartilage tissue.

Animals ; Bone Marrow Cells ; cytology ; metabolism ; Bone Morphogenetic Protein 7 ; Bone Morphogenetic Proteins ; biosynthesis ; genetics ; Cells, Cultured ; Genetic Vectors ; genetics ; Rabbits ; Recombinant Proteins ; biosynthesis ; Stromal Cells ; cytology ; metabolism ; Tibia ; cytology ; Transfection ; Transforming Growth Factor beta

OBJECTIVETo summarize clinical application of the sural medial gastrocnemius island muscle flap to cover wound of infection on upper region of the tibial.

METHODSNine patients (7 men, 2 women) with soft tissue defects on the upper region of the tibial underwent reconstruction with the sural medial gastrocnemius island muscle flap. The age ranged from 21 to 60 years old (mean, 34 years). The immediate coverage of the muscle flaps were performed by a meshed split-thickness skin graft. The donor site was closed directly. The donor leg was ipsilateral in all cases.

RESULTSOnly one case sustained superficial infection postoperative and the gradual wound healed by daily wound dressings. All the muscle flaps and skin graft had survived completely without major complication with satisfactory clinical results. All patients were followed-up for 13 months to 4 years (mean 21 months), the donor site was healing, there was no remarkable donor site morbidity.

CONCLUSIONThe sural medial gastrocnemius island muscle flap is nourished by the medial sural artery. The muscle flaps seem to have highly vascularize, a constant vascular anatomy and a long vascular pedicle. The muscle flap is thin and suitable for repairing soft tissue defect on the upper region of the tibial.

Adult ; Female ; Follow-Up Studies ; Humans ; Male ; Middle Aged ; Muscle, Skeletal ; cytology ; Reconstructive Surgical Procedures ; methods ; Surgical Flaps ; Tibia ; injuries ; Wound Infection ; surgery

OBJECTIVETo observe the efficacy of micro-arc oxidation and alkali-heat treatment (MAH) on Ti-24Nb-4Zr-8Sn (Ti2448).

METHODSDisks (diameter of 14.5 mm, thickness of 1 mm) and cylinders (diameter of 3 mm, height of 10 mm) were fabricated from Ti2448 alloy. Samples were divided into three groups: polished (Ti2448), micro-arc oxidation(MAO-Ti2448), micro-arc oxidation and alkali-heat treatment (MAH-Ti2448). MC3T3-E1 osteoblastic cells were cultured on the disks and cell morphology was observed with scanning electron microscopy (SEM) aftre 3 days. The cylinder samples were implanted in the tibia of dogs and implant-bone interface was observed with SEM after 3 months.

RESULTSA rough and porous structure was shown in both MAO and MAH group. The MC3T3-E1 cells on the MAH-Ti2448 discs spread fully in intimate contact with the underlying coarse surface through active cytoskeletal extentions. Osseointegration was formed in the implant-bone interface in MAH samples.

CONCLUSIONSMAH treatment can provide a more advantageous Ti2448 surface to osteoblastic cells than MAO treatment does, and the former can improve the implant-bone integration.

Alkalies ; Alloys ; chemistry ; Animals ; Cells, Cultured ; Dental Alloys ; Dogs ; Hot Temperature ; Mice ; Microscopy, Electron, Scanning ; Osseointegration ; Osteoblasts ; cytology ; Oxidation-Reduction ; Prostheses and Implants ; Prosthesis Implantation ; Surface Properties ; Tibia ; surgery

OBJECTIVETo study whether tissue engineered bone can repair the large segment bone defect of large animal or not. To observe what character the fascia flap played during the osteanagenesis and revascularization process of tissue engineered bone.

METHODS9 Chinese goats were made 2 cm left tibia diaphyseal defect. The repairing effect of the defects was evaluated by ECT, X-ray and histology. 27 goats were divided into three groups: group of CHAP, the defect was filled with coral hydroxyapatite (CHAP); group of tissue engineered bone, the defect was filled with CHAP + bone marrow stroma cells (BMSc); group of fascia flap, the defect was filled with CHAP + BMSc + fascia flap. After finished culturing and inducing the BMSc, CHAP of group of tissue engineered bone and of fascia flap was combined with it. Making fascia flap, different materials as described above were then implanted separately into the defects. Radionuclide bone imaging was used to monitor the revascularization of the implants at 2, 4, 8 weeks after operation. X-ray examination, optical density index of X-ray film, V-G staining of tissue slice of the implants were used at 4, 8, 12 weeks after operation, and the biomechanical character of the specimens were tested at 12 weeks post operation.

RESULTSIn the first study, the defect showed no bone regeneration phenomenon. 2 cm tibia defect was an ideal animal model. In the second study, group of CHAP manifested a little trace of bone regeneration, as to group of tissue engineered bone, the defect was almost repaired totally. In group of fascia flap, with the assistance of fascia flap which gave more chance to making implants to get more nutrient, the repair was quite complete.

CONCLUSIONSThe model of 2 cm caprine tibia diaphyseal defect cannot be repaired by goat itself and can satisfy the tissue engineering's demands. Tissue engineered bone had good ability to repair large segment tibia defect of goat. Fascia flap can accelerate the revascularization process of tissue engineered bone. And by this way, it augment the ability of tissue engineered bone to repair the large bone defect of goat.

Animals ; Bone Marrow Cells ; cytology ; Bone Marrow Transplantation ; Bone Regeneration ; physiology ; Bone Substitutes ; Cells, Cultured ; Durapatite ; Fascia ; transplantation ; Goats ; Implants, Experimental ; Neovascularization, Physiologic ; Osteogenesis ; Random Allocation ; Stromal Cells ; cytology ; Tibia ; blood supply ; injuries ; surgery ; Tibial Fractures ; surgery ; Tissue Engineering

PURPOSE: The purpose of this study was to investigate the effects of transplantation of an in vitro-generated, scaffold-free, tissue-engineered cartilage tissue analogue (CTA) using a suspension chondrocyte culture in a rabbit growth-arrest model. MATERIALS AND METHODS: We harvested cartilage cells from the articular cartilage of the joints of white rabbits and made a CTA using a suspension culture of 2x107 cells/mL. An animal growth plate defect model was made on the medial side of the proximal tibial growth plate of both tibias of 6-week-old New Zealand white rabbits (n=10). The allogenic CTA was then transplanted onto the right proximal tibial defect. As a control, no implantation was performed on the left-side defect. Plain radiographs and the medial proximal tibial angle were obtained at 1-week intervals for evaluation of bone bridge formation and the degree of angular deformity until postoperative week 6. We performed a histological evaluation using hematoxylin-eosin and Alcian blue staining at postoperative weeks 4 and 6. RESULTS: Radiologic study revealed a median medial proximal tibial angle of 59.0degrees in the control group and 80.0degrees in the CTA group at 6 weeks. In the control group, statistically significant angular deformities were seen 3 weeks after transplantation (p<0.05). On histological examination, the transplanted CTA was maintained in the CTA group at 4 and 6 weeks postoperative. Bone bridge formation was observed in the control group. CONCLUSION: In this study, CTA transplantation minimized deformity in the rabbit growth plate injury model, probably via the attenuation of bone bridge formation.
Animals ; *Bone Transplantation ; Cartilage/anatomy & histology ; Cell Culture Techniques ; Cells, Cultured ; Chondrocytes/*cytology/transplantation ; Growth Plate/anatomy & histology/*surgery ; *Mesenchymal Stem Cell Transplantation ; Rabbits ; Tibia/*surgery ; Tissue Engineering ; Transplantation, Autologous/methods ; Transplantation, Homologous

Few in vivo studies had previously been attempted in reaffirming the in vitro data in current literature. This study evaluated the ability of mesenchymal stem cells (MSCs) isolated from bone marrow, periosteum and fat to treat partial growth arrest in immature New Zealand white (NZW) rabbits. A physeal arrest model in an immature rabbit was created. The bony bridge was excised 3 weeks later, and MSCs from various sources were transferred into the physeal defect of different rabbits. Group I consisted of bone marrow-derived MSCs, Group II: periosteumderived MSCs, Group III: fat-derived MSCs. Contra-lateral tibiae, without undergoing operation, served as self-control. The animals were subsequently sacrificed, with radiological and histological analyses performed. All MSCs demonstrated chondrogenic and osteogenic differentiation potentials in vitro. In correction of varus angulation groups I and II exhibited superior results when compared to group III (P <0.05). The length discrepancies between operated and normal tibiae in groups I, II and III were significantly corrected when compared to the control group (P <0.01). In conclusion, bone marrow and periosteum derived stem cells provided better correction of physeal arrest in rabbits. The source of MSCs itself could influence the success in the treatment of growth arrest.
Animals ; Bone Diseases ; therapy ; Bone Regeneration ; Cell Culture Techniques ; methods ; Disease Models, Animal ; Growth Disorders ; therapy ; Mesenchymal Stem Cell Transplantation ; methods ; Mesenchymal Stromal Cells ; cytology ; Osteogenesis ; Rabbits ; Tibia ; growth & development ; injuries