Objective To evaluate the adhesion, proliferation and osteogenic differentiation of rabbits' mesenchymal stem cells (MSCs) cultured in demineralized bone matrix coated with OB-Cadherin. Method The second generation of MSC s were seeded onto the OB-Cadherin cover over allogenic frozen-dried demineralized bone matrix(FDBM) and the FDBM without OB-Cadhefin as control, and then both were cultured separably in vitro. The densities of seeded cells, the adhesion rate were measured, and their ALP activity was assayed in order to take it as an index of cell adhesion, proliferation and osteogenic differentiation. The growth and adhension of MSCs on the FDBM was observed and evaluated microscopically and electronic scanning microscopically. Data were ex-pressed as means and standard deviation (x±s), and were analyzed with SPSS 12.0. Independent-Sanples T-test and Paired t test was used, and P<0.05 indicated statistically significant. Results There was no significant dif-ference in cell proliferation between modified FDBM and unmodified FDBM cultured fot 7, 14, 21 d. ays. After culture for 20 hours, the adhesion rate in the control group was (35.56±1.75)%, the densities of seeded cells were less than 2.7×104. The adhesion rate of cells in the modified group was consistent at 80%, whereas the densities of seeded cells were as high as 5.0×105 compared with control group (P<0.01). After cultured for 20 hours, the efficiency of cell adhesion in the modified FDBM was higher than that in the unmodified FDBM. After cultured for 7 days, the cultured MSC on modified FDBM expressed higher AIP activity, and after cultured for 14 days, the ALP activity on modified FDBM was much higher than that on unmodified FDBM (p<0.01). After cultured for 14 days, osteocalcin immunohistochemical positive rate of modified group was (71±11)%, while that of the control group was(49±8)% with significant difference Conclusion OB-Cadherin enhances cell adhesion to FDBM and promotes MSC to differentiate to osteoblast, but no obvious effects d OB-Cadherin on cell proliferation were observed.

Objective To detect the impact of reactive oxygen species ( ROS) on mitochondrial morphology and distri-bution during mitosis.Methods A viral vector in which the fluorescence gene was specifically under the control of mito-chondrial promoter was constructed and confirmed through DNA sequencing and Western blotting.After transfecting HeLa s3 cell with packaged virus, the HeLa s3-COX4tp-EGFP cell line stably expressing the mitochondrial fluorescence signal was obtained.With immunofluorescent staining, the impact of ROS on the morphology and distribution of mitochondria dur-ing mitosis was inspected.Result The cell line constantly expressing mitochondrial fluorescence signals was successfully constructed.Meanwhile,it was found that H2 O2 treatment could significantly change the morphology and distribution of mi-tochondria during mitosis by confocal microscopy.Conclusion Our study demonstrates that ROS can affect the morphology and distribution of mitochondria during mitosis.This research help study the relationship between the mitochondrial function and the regulation of mitosis in the future.

Mechanical properties and biological evaluation of buffalo horn material were examined in this study. The effects of sampling position of buffalo horn on mechanical properties were investigated with uniaxial tension and micron indentation tests. Meanwhile, the variation of element contents in different parts of buffalo horn was determined with elemental analysis, and the microstructure of the horn was measured with scanning electron microscopy. In addition, biological evaluation of buffalo horn was studied with hemolytic test, erythrocyte morphology, platelet and erythrocyte count, and implantation into mouse. Results showed that the buffalo horn had good mechanical properties and mechanical characteristic values of it gradually increased along with the growth direction of the horn, which may be closely related to its microstructure and element content of C, N, and S in different parts of the buffalo horn. On the other hand, because the buffalo horn does not have toxicity, it therefore does not cause hemolysis of erythrocyte and has a good affinity with it. Buffalo horn has good histocompatibility but meanwhile it may induce the platelet adhesion and aggregation. Even so, it does not continue to rise to induce a large number of platelet to aggregate with resulting blood clotting. Therefore, the buffalo horn material has been proved to possess good blood compatibility according to the preliminary evaluation.
Animals ; Biocompatible Materials ; Biomechanical Phenomena ; Buffaloes ; Erythrocytes ; Horns ; chemistry ; ultrastructure ; Mice ; Microscopy, Electron, Scanning