BACKGROUND: Natural bilogical bone-derived materials processed with physical and chemical methods possess natural network pore system. They have good cellular compatibility, and help osteoblasts attach and grow on them, and can be used as the scaffolds of osteoblasts.OBJECTIVE: To observe the osteogenetic effect of partially deproteinised decalcified bone (PDDB) as scaffolds of osteoblasts in vivo.DESIGN: A randomized and controlled trial.SETTING: Central Laboratory of the First Hospital of Kunming Medical College.MATERIALS: Partially deproteinised decalcified bone; human embryonic periosteum-derived osteoblasts; twenty 4-week-old BALB/c nude mice,with the body mass of 25 to 28 g, of either gender.METHODS: This experiment was conducted at the Central Laboratory of the First Affiliated Hospital of Kuming Medical College from January to June 2003. PDDB composited with human embryonic periostea-induced osteoblasts were implanted into the nude mice after cultured for 1 week in vivo, 4 scaffolds in each nude mouse. Composite of scalfolds and cells implanted on the left side of the spine was set as experimental side and simple implanted material on the right side of the spine was set as blank control side. Then alkaline phosphatase activity and routine histological examination were performed 4 and 8 weeks after operation.MAIN OUTCOME MEASURES: General observation, alkaline phosphatase activity and routine histological examination were performed after the materials were taken out.RESULTS: Twenty nude mice entered the stage of result analysis. ① General observation of the implanted materials: No necrosis, ecpyesis, or fluidifying was found around the implanted materials, but ingrowth and enwrapption of soft tissues were found. ② Measurement of alkaline phosphatase activity: alkaline phosphatase activity after PDDB composited osteoblasts in vivo was stronger at week 8 than at week 4 [(22.854±6.018) nkat/g vs(11.286±4.268) nkat/g], and was much stronger than that of the simple implanted materials [(1.217±0.083) nkat/g vs (2.717±0.583) nkat/g]. ③ Results of routine histological examination: Cartilage formed at week 4 and part of cartilage formed new bone and marrow cavity at week 8 at the experimental side, cartilage and new bone formed much more as time went by, but there was no any cartilage or bone formation at the control side.CONCLUSION: Cartilage and bone form after PDDB composited with osteoblasts are implanted, and more cartilage and new bone form as time passes. PDDB can be used as the scaffolds of osteoblasts.

The research in bone tissue engineering is abundant and its development is rapid,however,there has been no ideal scaffold materials.We review the recent articles on bone tissue engineering,including ceramics materials,polymerized materials,materials deriver from natural biological organism and their compound materials

Objective:To investigate the effect of BMSCs transplantation plus hyperbaric oxygen (HBO) on repair of rat SCI. Methods:Seventy five male rats were divided randomly into five groups:sham, vehicle, BMSCs transplantation group, combination group, 15 rats in each group. Every week after the SCI onset, all animals were evaluated for behavior outcome by Basso-Beattle-Bresnahan (BBB) score and inclined plane test. Axon recovery was examined with focal spinal cord tissue by electron microscope at 6 weeks after the SCI onset. HE staining and BrdU staining were performed to examine the BMSCs and lesion post injury. Somatosensory evoked potential (SEP) testing was performed to detect the recovery of neural conduction. Results:Results from the behavior tests from combination group were significant higher than rats which received only transplantation or HBO treatment. Results from histopathology showed favorable recovery from combination group than other treatment groups. The number of BrdU+ in combination group were measureable more than transplantation group (P<0.05). The greatest decrease in TNF-α, IL-1β, IL-6, IFN-αdetermined by Elisa assay in combination group were evident too. Conclusions:BMSCs transplantation can promote the functional recovery of rat hind limbs after SCI, and its combination with HBO has a synergistic effect.

BACKGROUND:The existed femoral head necrosis(FHN)model can not reflex the clinical necrosis of femoral head correctly.Microwave heating provides a new approach for model preparation.but the concrete standard remains uncertain.OBJECTIVE:To study the optimal temperature and time jn preparing a FHN model induced by microwave heating.METHODS:Totally 48 rabbits were randomly divided into 4 groups on the basis of the microwave temperature(50,55,60℃)and heating time(10,20 minutes).The microwave antenne was inserted into the rabbit femoral head.The rabbits were sacrificed immediately and at 1,2,4,8 and 1 2 weeks after operation.A series of examinations were performed including gross observation,X-ray.histology and MRI to observe the femoral head necrosis and repair status.RESULTS AND CONCLUSION:Marrow partially solidified in the group(50℃,10 minutes)at 1 week,and the osteonecrosis returned to normaI at 8 weeks after operation.1n the group(55℃,10 minutes),marrow was completely coagulated at 1 week and low signal on T1 weighted images and increased signal on T2 images were identified at 2 weeks.Osteonecrosis and repair occurred at the same time at 4 weeks.At 12 weeks,the osteonecrosis continued and the repair stopped,and the femorel heads started to collapse.All femoral heads collapsed at 8 weeks in group(50℃,20 minutes)and group(60℃,10 minutes).Accordingly.microwave heating is a good method in developing FHN model.55℃ and 10 minutes are the optimal temperature and time for the development of FHN model of rabbits induced by microwave heating.