New research progress on atrophic nonunion / 中国骨伤

Occurance of atrophic nonunion is a complex process. Previous studies suggested that atrophic nonunion was mainly due to lack of blood supply of fracture fragments, but recent studies found that blood supply was not deficiency in middle and late stages, indicating that decreased osteogenic factors and blood supply in early stages might play an important role in morbidity. Current effective treatment measures for atrophic nonunion mainly include bone graft and fixation,physical therapy, local injection therapy. All-round preventive could reduce incidence of atrophic nonunion. Atrophic nonunion is still a troublesome complication of fractures in orthopaedics, and more attention should be paid for its effective prevention and treatment. The paper summarized recent original articles about atrophic nonunion and reviewed the occurrence mechanisms, diagnosis, prevention and treatment measures of this disease.

Hsa-miR-654-5p regulates osteogenic differentiation of human bone marrow mesenchymal stem cells by repressing bone morphogenetic protein 2 / 南方医科大学学报

<p><b>OBJECTIVE</b>To study the effect of hsa-miR-654-5p in repressing bone morphogenetic protein 2 (BMP2) mRNA and protein in human bone marrow mesenchymal stem cells (hBMSCs), and explore its regulatory role in osteogenic differentiation of hBMSCs.</p><p><b>METHODS</b>hBMSCs in the 4th passage were cultured for 16 h and transfected with hsa-miR-654-5p followed by further culture for 48 h. qRT-PCR and Western blotting were performed to detect the expressions of BMP2 mRNA and protein. Dual-luciferase?reporter gene assay was employed to examine the repression of the BMP2 gene.</p><p><b>RESULTS</b>BMP2 mRNA and protein expressions were significantly down-regulated in hBMSCs with hsa-miR-654-5p overexpression. Dualluci-ferase reporter gene assay indicated that the predicted target site of BMP2 was repressed directly by hsa-miR-654-5p, but this repression did not occur at the mutant predicted target site of BMP2.</p><p><b>CONCLUSION</b>hsa-miR-654-5p can directly repress the mRNA and protein expressions of BMP2 by binding to a specific target site. The changes in hsa-miR-654-5p can play an important role in osteogenic differentiation regulation of hBMSCs.</p>