Objective:To investigate the feasibility of using marrow stromal cells (MSC) as seed cells and three-dimensional porous nano-hydroxylapatite as scaffolds for constructing tissue-engineered bone.Methods:MSC from rat were cultured and induced to differentiate into osteoblasts in vitro. And then these induced cells were identified and seeded onto three-dimensional porous nano-hydroxylapatite scaffolds, cultured for 15 days in vitro. Scanning electron microscopy was used to evaluate the growth of these induced cells on three-dimensional porous nano-hydroxylapatite scaffolds. Results: The activity of alkaline phosphatase (ALP) and the secretion of osteocalcin of MSC from rat appeared and were increased gradually along the culture. The cells seeded on three-dimensional porous nano-hydroxylapatite scaffolds could adhere and proliferate well, and come into being many tiny calcium nodules and collagenous fibers. Conclusion:The data demonstrated that the new developed culture method is conducive to MSC’s differentiating and proliferating into osteoblasts that have a fine activity and the three-dimensional porous nano-hydroxylapatite may be considered as a suitable scaffold for the seeded cells. Using marrow stromal cells as seed cells and three-dimensional porous nano-hydroxylapatite as scaffolds is advantageous for constructing tissue-engineered bone.

Objective:Because of the lower proliferation ability of periodontal ligament cells of elderly people,how to choose suitable scaffold materials for them becomes very important.The aim of this study was to observe the morphological manifestation of the periodontal ligament cells of elderly people seeded onto the three-dimensional porous nano-hydroxylapatite scaffolds.Methods: Periodontal ligament cells from elderly people were seeded onto the three-dimensional porous nano-hydroxylapatite scaffolds,cultured for 15 days in vitro,and observed for the morphological changes by scanning electron microscopy in comparison with those of young people.Results:Fifteen days after seeded on the three-dimensional porous nano-hydroxylapatite scaffolds,the periodontal ligament cells of the elderly people exhibited sufficient adhesive behavior,proliferated well and produced tiny calcium nodules,but the number of the nodules was smaller than that in the young people.Conclusion: The periodontal ligament cells of elderly people grow well on three-dimensional porous nano-hydroxylapatite scaffolds,and can be considered as a suitable scaffold for periodontal tissue engineering in elderly people.

To investigate the ability of composite graft of osteobalsts and deproteinized bone-titanium mesh (DPB-TM) scaffold to repair cranial bone defect. 30 rabbits were randomly divided into 3 groups. The passage 3 fetal rabbit osteoblasts were seeded into porous DPB-TM scaffolds at the density of 5 x 10(6) ml(-1) as the experimental group. The same defects were respectively reconstructed by DPB-TM or osteoblasts as the control groups. After 12 weeks, the result was evaluated by three-dimensional computed tomographic scanning, gross inspection, scanning electron microscopy, histological examination and mechanics test, respectively. In the experimental group, bone trabecula was observed to pass the defect and interface was mixed. No demarcation between the region of the bone defect and the normal bone was observed. There was plenty of new bone on the scaffold. Part of the scaffold was absorbed. In view of mechanics, the intensity of artificial bone (18.93+/-1.12 MPa) was higher than that of normal bone (16.96+/-1.60 MPa) (P<0.05). In the control groups, only fibrous tissue was observed in the defect region, there was no new bone formation. The tissue engineering bone constructed by osteoblasts and DPB-TM scaffold can be applied to the repair of bone defect.
Animals ; Bone Regeneration ; Bone Substitutes ; Cell Separation ; Cells, Cultured ; Female ; Fetus ; Guided Tissue Regeneration ; Implants, Experimental ; Male ; Osteoblasts ; cytology ; Osteogenesis ; Prostheses and Implants ; Rabbits ; Random Allocation ; Skull ; injuries ; surgery ; Swine ; Tissue Engineering ; Titanium

There is close relationship between the morphologic changes of peripheral nerve after injury and its function recovery during regeneration. In our experiment, the sciatic nerve of rats was transected and bridge-connected with silicone tube, and the images of serial slices of different time and different injury parts were taken by micro-photograph system. The volume unit model was applied to rendering the three dimensional (3D) structure of degenerative and regenerative sciatic nerve fiber and its affiliated structure after injury. The 3D images showed that node of Ranvier had not formed and its array was turbulent, both the myelin sheath and the axis-cylinder were thinner, and the collagen fibres had proliferated.
Animals ; Male ; Nerve Regeneration ; physiology ; Rats ; Rats, Wistar ; Recovery of Function ; Sciatic Nerve ; injuries ; pathology ; physiopathology