A study of the different effect on the expression of calcitonin gene related peptide and neuropeptide Y in tissue engineered bone with vascular bundle graft in vivo and that with sensory nerve tract graft in vivo / 中华外科杂志

<p><b>OBJECTIVE</b>To evaluate the different effect on the expression of Calcitonin gene related peptide (CGRP)and neuropeptide Y (NPY) between tissue engineered bone with vascular bundle graft in vivo and that with sensory nerve tract graft in vivo.</p><p><b>METHOD</b>Thirty-six healthy New Zealand rabbits were divided into 3 groups randomly and equally: vascular bundle group (A), sensory nerve tract group (B), tissue-engineering group (C). Group A segmental bone defect of 1.5 cm long was made at the right femur in each animal. After plate fixation, the defects were implanted respectively with the engineered bone prepared in the above-mentioned 3 methods. At 3, 6 and 12 months post-operatively, the distribution of CGRP and NPY in the new bone were detected by immunohistochemistry and analyzed semi-quantitatively by image analysis software.</p><p><b>RESULTS</b>CGRP and NPY immuno-histochemical results indicated their contents increased significantly in all 3 groups as time passed (P = 0.000). Compared with group B, the contents of CGRP and NPY in group A significantly increased at 3 months (P = 0.000), but there was no statistic difference between them at 6 or 12 months (P > 0.05). The expression of CGRP and NPY in both group A and B were significantly more than that in group C at 3, 6 or 12 months (P = 0.000).</p><p><b>CONCLUSION</b>Implantation of vascular bundle into tissue-engineered bone can significantly improve the CGRP and NPY contents at early 3 months comparing with Implantation of sensory tract into tissue-engineered bone, but the changes are not significant at 6 or 12 months post-operatively.</p>

Effect of rabbit peripheral sensory and motor nerve homogenates on the proliferation and calcification of rabbit osteoblasts in vitro / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effect of rabbit saphenous and sciatic nerve homogenates on the proliferation and calcification of rabbit osteoblasts in vitro.</p><p><b>METHOD</b>The saphenous nerves (sensory nerves) and the muscular branches of the sciatic nerve (motor nerve) were collected from 48 New Zealand white rabbits to prepare the nerve tissue homogenates. Bone marrow mesenchymal stem cells (MSCs) were isolated from the rabbits and cultured in vitro, and after 14 days of routine osteogenic induction, the resultant osteoblasts were identified by immunohistochemistry, alkaline phosphatase (ALP) and Alizarin red S staining. The osteoblasts were then incubated in the induction medium containing the saphenous (sensory nerve group) or sciatic homogenates (motor nerve group), with the cells in the dexamethasone-containing, dexamethasone-free osteogenic induction medium and control medium as the control. The proliferation, total protein and ALP activity of the osteoblasts were measured every other day until the 8th day, and Alizarin red S staining was used for quantitative analysis of calcification of the cells after two weeks.</p><p><b>RESULTS</b>The application of the saphenous nerve homogenates significantly promoted cell proliferation, total protein and ALP activity (P<0.01, P<0.05 and P<0.05), while exposure of the osteoblasts to dexamethasone inhibited the cell proliferation (P<0.001). Compared to dexamethasone-free group, the saphenous homogenates enhanced the mineralization of the osteoblasts (P<0.001).</p><p><b>CONCLUSION</b>Saphenous nerve homogenates significantly promotes the proliferation, differentiation, ALP activity and mineralization of rabbit osteoblasts, but sciatic nerve homogenates do not show osteogenic effects on the cells.</p>

Adenoviral vector-mediated human hepatocyte growth factor gene transfection for its high expression in rabbit bone marrow-derived mesenchymal stem cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To obtain high expression of human hepatocyte growth factor (HGF) in passaged rabbit bone marrow-derived mesenchymal stem cells (BMSCs) via recombinant adenovirus vector mediated HGF gene transfection, and explore the feasibility of this strategy for local treatment of avascular necrosis of the femoral head (ANFH).</p><p><b>METHODS</b>HGF gene was subcloned into the adenovirus shuttle plasmid pDC316, and the products were co-transfected into HEK293 cells with the helper plasmid pBHGlox deltaE1,3Cre. The recombinant adenovirus Ad-HGF was generated by homologous recombination of the 2 plasmids in HEK293 cells. After PCR identification, Ad-HGF was amplified and purified and its titer measured by TCID50 assay before transfected into the second passage of rabbit BMSCs. The transcription and expression of HGF gene in the transfected BMSCs was detected by RT-PCR, in situ hybridization, and immunological histochemistry.</p><p><b>RESULTS</b>Ad-HGF was successfully constructed with a titer of 2.6x10(10) TCID50/ml. The expressions of HGF mRNA and protein were confirmed in the transfected BMSCs.</p><p><b>CONCLUSION</b>Ad-HGF transfection allows efficient expression of HGF protein in rabbit BMSCs, and this success may facilitate further study of local treatment of ANFH using HGF-expressing BMSCs.</p>