Objective: To observe serum and callus leptin expression within the setting of fracture and traumatic brain injury (TBI).Methods: Atotal of 64 male SD rats were randomized equally into 4 groups: nonoperated group...Objective: To observe serum and callus leptin expression within the setting of fracture and traumatic brain injury (TBI).Methods: Atotal of 64 male SD rats were randomized equally into 4 groups: nonoperated group, TBI group, fraeture group, and fracture+TBI group. Rats were sacrificed at 2, 4, 8 and 12 weeks after fracture+TBI. Serum leptin was detected using radioimmunoassay, and callus formation was measured radiologically. Callus leptin was analyzed by immunohistochemistry.Results: Serum ieptin levels in the fracture group, TBI group and combined fracture+TBI group were all significantly increased compared with control group at the 2 week time-point (P〈0.05). Serum leptin in the combined fracture +TBI group was significantly higher than that in the fracture and TBI groups at 4 and 8 weeks after injury (P〈0. 05).The percentage of leptin-positive cells in the fracture+TBI callus and callus volume were significantly higher than those in the fracture-only group (P〈0.01).Conclusions: We demonstrated elevated leptin expression within healing bone especially in the first 8 weeks in a rat model of fracture and TBI. A close association exists between leptin levels and the degree of callus formation in fractures.展开更多
Objective: To evaluate the effect of osteoporosis on fracture healing through observing the histomorphological changes, bone mineral density of callus and expression and distribution of transforming growth factor beta...Objective: To evaluate the effect of osteoporosis on fracture healing through observing the histomorphological changes, bone mineral density of callus and expression and distribution of transforming growth factor beta 1 (TGF β1),basic fibroblast growth factor (bFGF) and bone morphogenetic protein 2 (BMP 2) in ovariectomized rats. Methods: Sixty female Sprague Dawley rats (aged 12 weeks and weighing 235 g on average) were randomly divided into an ovariectomized (OVX) group (n=30) and a sham operated (SO) group (n=30). Ovariectomy was performed in the OVX rats and same incision was made in the SO rats. Three months later, fracture of femoral shaft was made on all the rats. Then they were killed at different time points. Callus formation was observed with histological and immunohistochemical methods. Results: A reduction in callus and bone mineral density in the healing femur and a decrease of osteoblasts expressing TGF β1 near the bone trabecula were observed in the OVX rats 3 4 weeks after fracture. Histomorphological analysis revealed a higher content of soft callus in the OVX rats than that in the SO rats. Immunohistochemistry results showed that no remarkable difference in expression and distribution of BMP 2 and bFGF between the OVX and SO groups was found. Conclusions: Osteoporosis influences the quantity and quality of callus during the early period of fracture healing. The effect of osteoporosis on fracture healing has no relationship with the expression of BMP 2 or bFGF. The decreased expression of TGF β1 in osteoblasts may cause a decrease in quality of facture healing after osteoporosis.展开更多
文摘Objective: To observe serum and callus leptin expression within the setting of fracture and traumatic brain injury (TBI).Methods: Atotal of 64 male SD rats were randomized equally into 4 groups: nonoperated group, TBI group, fraeture group, and fracture+TBI group. Rats were sacrificed at 2, 4, 8 and 12 weeks after fracture+TBI. Serum leptin was detected using radioimmunoassay, and callus formation was measured radiologically. Callus leptin was analyzed by immunohistochemistry.Results: Serum ieptin levels in the fracture group, TBI group and combined fracture+TBI group were all significantly increased compared with control group at the 2 week time-point (P〈0.05). Serum leptin in the combined fracture +TBI group was significantly higher than that in the fracture and TBI groups at 4 and 8 weeks after injury (P〈0. 05).The percentage of leptin-positive cells in the fracture+TBI callus and callus volume were significantly higher than those in the fracture-only group (P〈0.01).Conclusions: We demonstrated elevated leptin expression within healing bone especially in the first 8 weeks in a rat model of fracture and TBI. A close association exists between leptin levels and the degree of callus formation in fractures.
文摘Objective: To evaluate the effect of osteoporosis on fracture healing through observing the histomorphological changes, bone mineral density of callus and expression and distribution of transforming growth factor beta 1 (TGF β1),basic fibroblast growth factor (bFGF) and bone morphogenetic protein 2 (BMP 2) in ovariectomized rats. Methods: Sixty female Sprague Dawley rats (aged 12 weeks and weighing 235 g on average) were randomly divided into an ovariectomized (OVX) group (n=30) and a sham operated (SO) group (n=30). Ovariectomy was performed in the OVX rats and same incision was made in the SO rats. Three months later, fracture of femoral shaft was made on all the rats. Then they were killed at different time points. Callus formation was observed with histological and immunohistochemical methods. Results: A reduction in callus and bone mineral density in the healing femur and a decrease of osteoblasts expressing TGF β1 near the bone trabecula were observed in the OVX rats 3 4 weeks after fracture. Histomorphological analysis revealed a higher content of soft callus in the OVX rats than that in the SO rats. Immunohistochemistry results showed that no remarkable difference in expression and distribution of BMP 2 and bFGF between the OVX and SO groups was found. Conclusions: Osteoporosis influences the quantity and quality of callus during the early period of fracture healing. The effect of osteoporosis on fracture healing has no relationship with the expression of BMP 2 or bFGF. The decreased expression of TGF β1 in osteoblasts may cause a decrease in quality of facture healing after osteoporosis.