[Objective]To sturdy the biological responses of osteoblast-like cells in different maturation stages under shear flow.[Method]Flow chamber system was used to apply shear flow stimulation of 4.62dyn?s/cm~2 for 2 hours on osteoblast-like cell MC3T3-E1 of different maturation stage induced by osteogenic media,and then samples for dsDNA content and ALP activity analysis were collected.[Result]On 24 hours after simulation,there was not obvious change of ALP activity with non-osteogenic inducing group,an increase was observed in the group of 4 days of differentiation,while an decrease in the group of 8 days of differentiation.[Conclusion]Biological responses of osteoblast-like cells in different maturation stages under shear flow is quite different,and this may be an important role in bone growth and reconstruction.

Objective:To investigate the enhancing effect of bone marrow stroma cell(BMSC)on the functional recovery of injured spinal cord by observing the formation of gliotic scar,cavity volume and the cascade of apoptosis of neural cells.Methods:Eighty spinal cord injury(SCI)rat models were made and randomly divided into two groups:group A(n=40),the control group without any treatment;group B(n=40),the injured animals treated with BMSC implantation.The behavioral evaluation was performed using Basso,Beattie and Bresnahan(BBB)scoring system.Scores were recorded at time points of 1,2,4,6 and 8 weeks after transplantation.After 8 weeks,rats were sacrificed.The immunoreactivity of Nogo-A,glial fibrillary acidic protein(GFAP)and the cavity area were measured.The cell apoptosis was detected by TUNEL methods at 1,2,3,7 and 14 days after injury.Results:Compared with control group,treated animals gained higher scores after 8 weeks of transplantation.The number and the size of reactive astrocytes,the average volume of cavity,TUNEL positive cells,the expression of Nogo-A and GFAP reduced significantly in group B compared with those of group A(P＜ 0.05).Conclusion:BMSC possess effects on repairing injured spinal cord and promoting functional recovery through various mechanisms.

Objective To construct the eukaryotic expression plasmid of recombinant human hypoxia-inducible factor-1?(HIF-1?) and get ready for the coloning and expressing of HIF-1? gene. Methods The total RNA was isolated from blood cells,and cDNA library was constructed by reverse transcription PCR method.PIREGFP containing EGFP fragment and cDNA were used as templet,the three designed primers (EGFP-linker,HIF-1? upstream and HIF-? downstream)were put into,after amplification the target gene fragment was inserted into the shuttle vector T,and transfected with E.coli DH5?,the bacterial colonies containing recombinant plasmids were identified by LB/KANA-agar plate,and the recombinant plasmids were extracted and purified.All sequences amplified by PCR were confirmed by complete sequencing.The correct sequences were cloned into the pVAX1 vector.Results The amplified fragments were about 870,1 199,672 bp by PCR,they were inserted into the shuttle vector T and sequenced. The result of sequencing was identical with that provided by GenBank.The final plasmid about 1 800 bp was obtained by the identification of enzyme digestion and it had same molecular size as expected.Conclusion The eukaryotic expression plasmid pVAX1-EGFP-linker-HIF-1? of recombinant human HIF-1? is successfully constructed.

Objective To evaluate the diagnostic value of tracking movement of normal patellar using volume scan on sensation 320 CT. Method Data of dynamic scans of 30 knees was collected using the motor function of 320 CT and retrospectively analyzed. The data of movement of the patellorfemoral joint was obtained during flexion (from 0° to 120°) within 10-sec by 320 CT from all volunteers. The 3D coordinate of the center of patella was recorded to investigate the dispose relation of patellofemoral joint.Result With the knee angle changed from 0° to 90°, the patella moved rapidly along the Y-axis direction ( sagittal plane) down about (53.87 ± 0. 45 ) mm, and then entered the plateau phase with little change.When the knee flexion reached 10°-30° ,the patellar movement along the X-axis reached the largest range of (2. 31 ±0. 52)-(3.36 ± 0. 43 ) mm, and subsequently moved to the opposite lateral direction with the maximum about (8. 53 ± 0. 44 ) mm at 120°. In the Z axis, the track initially showed plateau, and then presented a rapidly downward trend after 30°. The patellar tracking is like an outward arc during the whole knee flexion. Conclusion The motor functional imaging of 320 CT can pinpoint the patelar tracking in a fast, painless way.

Objective To investigate the effects of SAHA on the differentiation of human hepatocellular carcinoma(HCC)SMMC-7721 cells.Methods Cell morphology was examined by light microscopy;Cell viability was determined by MTT assay;The expression of Alpha-fetoprotein(AFP)and proliferating cell nuclear antigen(PCNA)was analyzed with immunocytochemistry;Flow cytometry(FCM)was used to investigate the cell cycle;The expression of p21 WAF1 mRNA was detected by semi-quantitative RT-PCR.Results Light microscopy showed that SMMC-7721 cells induced by SAHA underwent restorational alterations in morphology which were different from those of nontreated cells but were similar to those of normal cells;MTT assay showed that SAHA inhibited the proliferation of SMMC-7721 cells in a dose-dependent and time-dependent way;Immunocytochemistry assay showed that the expression of AFP and PCNA decreased significantly;FCM analysis showed SAHA could arrest SMMC-7721 cells at G0/G1 phase,with an accumulation of the cells at G0/G1 phase while a decrease of cells at S phase;Semi-quantitative RT-PCR detection revealed that the expression of p21 WAF1mRNA was upregulated remarkably in the cells treated with SAHA.Conclusion SAHA could induce differentiation of human HCC SMMC-7721 cells inhibiting enzymatic activity of HDAC,upregulating the expression of p21 WAFlmRNA as well as causing arrest of HCC cells at G0/G1 phase.

AIM: To investigate the effects of proteasome inhibitor Z-LLL-CHO(MG132) on human osteosarcoma cell line MG-63 and its possibly mechanism.METHODS: After treated with different concentration of MG132,the morphological change,ultrastructral morphology,cell viability,cell apoptosis,gene transcription and protein expression in MG-63 cells were accessed by fluorescence microscope,electron microscope,MTT assay,agrose gel electrophoresis,FCM,RT-PCR and Western blotting.RESULTS: Proteasome inhibitor MG132 was an effective inducer of apoptosis in human osteosarcoma MG-63 cells.Not only apoptotic changes,but also cell arrest at G2-M-phase,the accumulation of p27kip1,the accumulation of activated caspase-8 and increased ratio of Bax∶Bcl-2 were observed.However,to normal human diploid fibroblast cells,MG132 did not show apoptosis-inducing effect.CONCLUSION: Apoptosis induced by MG132 may be caspase-8,p27kip1and bcl-2-related.

In recent years,stem cell research has been developing quickly in biological science.As the key of regenerative medicine,stem cell therapy becomes another innovative treatment following drug therapy and surgery.In vivo stem cell tracking,including optical imaging,radionuclide imaging and MRI,can trace the viability,distribution and function of engrafted cells.Multimodal imaging integrates two or more types of imaging techniques to obtain the combined advantages of each technology,and therefore is able to accurately and effectively trace stem cell in vivo,hopefully promoting its clinical transformation.This paper reviews the application of multimodal imaging in stem cell research.

Objective To identify the application of puncture biopsy under ultrasound guidance in diagnosis of bone tumor.Methods The results of ultrasonic puncture biopsy were comparatively analysed with that of imaging diagnosis and postoperative-pathological diagnosis in 17 patients with bone tumors.Results The giant cell tumor of bone were diagnosed by puncture biopsy in 8 cases,by imaging in 12 cases and by pathology,postoperation in 9 cases,the corresponding rate was 66.7% and 88.9% respectively.Bone cyst in 2 cases,fibrous dysplasia in 2 cases,metastasis from lung carcinoma in one case,osteosarcoma in 2 cases were confirmed by both pathology and puncture biopsy.The aneurysmal bone cyst in one case was diagnosed by imaging,but no blood-like fluid was harvested in puncture,one case of metastasis in proximal femur,one case of fibrous dysplasia and one case of osteosarcoma were diagnosed by imaging,while one case,2 cases and one case diagnosed by puncture respectively.One case of bone cyst was confirmed by imaging,puncture biopsy and pathology.Conclusion The puncture biopsy under ultrasound guidance is of high diagnostic rate in bone tumors,it is a good choice for the diagnosis of bone tumor.

Objective To explore the relation of the expressions of MDM2 and VEGF in osteosarcoma with the pathological parameters and prognosis of the tumor.Methods The expressions of MDM2 and VEGF were detected with immunohistochemical(SP) method in specimens from 56 cases of osteosarcoma.The correlation between the expressions of MDM2,VEGF and pathological grade,metastasis and prognosis was analyzed statistically.while 8 cases of fibrous dysplasia of bone were used as negative control group.Results The positive rates of MDM2 and VEGF in osteosarcoma were 64.3%(36/56) and 67.9%(38/56),respectively .MDM2 and VEGF didn't express in negative control group.The expression of MDM2 and VEGF were not significantly correlated to the pathological grades of the osteosarcoma,but which were significantly correlated with tumor metastasis and prognosis(P