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Background: Several studies suggested that celecoxib interferes with bone healing while others contradict these findings. This study was conducted to investigate the effects of celecoxib on bone healing in rats femur mold with a dose based on body surface area conversion. Materials and Methods: 72 adult female Sprague Dawley rats were randomly divided into three groups after the internal fixation operation of nondisplaced transverse mid diaphyseal fractures of the right femurs. Each group was treated with 1% methylcellulose, celecoxib (21 mg/kg/d) for 1 week, or celecoxib (21 mg/kg/d) for 4 weeks after surgeries respectively. Bone healing scores and callus formation were evaluated by radiographs at 3, 4, 6 weeks after surgeries. Half of these rats were sacrificed for histological analysis at 4 weeks after surgery. The remaining fractured femurs were evaluated by biomechanical tests at 6 weeks after surgery. Results: The mean radiographic scores for fracture healing of both short and long term groups were lower than that of the control group and the differences among the three groups were statistically significant (P < 0.05) at 3, 4, 6 weeks after surgery. The mean bone trabecula density of both groups was smaller than that of the control group and the differences were also statistically significant ( P < 0.05) at 4 week. The maximum load, total energy and stiffness in both the short term and long term groups were significantly decreased compared with those in the control group ( P < 0.05) at 6 week. Conclusion: Both short term and long term sustained use of celecoxib in rat models has significantly inhibitory effects on rat fracture healing. [ABSTRACT FROM AUTHOR]

Background: The clinical relationship between medial meniscus tear and anterior cruciate ligament (ACL) rupture has been well documented. However, the mechanism of this clinical phenomenon is not exactly explained. Our aim is to investigate the biomechanical impact of partial and complete ACL rupture on different parts of medial meniscus. Materials and Methods: Twelve fresh human cadaveric knee specimens were divided into four groups: ACL intact (ACL-I), anteromedial bundle transection (AMB-T), posterolateral bundle transection (PLB-T), and ACL complete transection (ACL-T) group. Strain on the anterior horn, body part, and posterior horn of medial meniscus were measured under 200 N axial compressive tibial load at 0°, 30°, 60°, and 90° of knee flexion, respectively. Results: Compared with the control group (ACL-I), the ACL-T group had a higher strain on whole medial meniscus at 0°, 60°, and 90° of flexion. But at 30°, it had a higher strain on posterior horn of meniscus only. As to PLB-T group, strain on whole meniscus increased at full extension, while strain increased on posterior horn at 30° and on body of meniscus at 60°. However, AMB-T only brought about higher strain at 60° of flexion on body and posterior horn of meniscus. Conclusions: Similar to complete rupture, partial rupture of ACL can also trigger strain concentration on medial meniscus, especially posterior horn, which may be a more critical reason for meniscus injury associated with chronic ACL deficiency. [ABSTRACT FROM AUTHOR]

Background: Epimedii herba is one of the most frequently used herbs in formulas that are prescribed for the treatment of osteoporosis in China and its main constituent is Epimedium pubescen flavonoid (EPF). However, it is unclear whether EPF during chronic exposure to cigarette smoke may have a protective influence on the skeleton.The present study investigated the effect of EPF on bone mineral status and bone turnover in a rat model of human relatively high exposure to cigarette smoke.Methods: Fifty male Wistar rats were randomized into five groups: controls, passive smoking groups and passive smoking rats administered EPF at three dosage levels (75, 150 or 300 mg/kg/day) in drinking water for 4 months.A rat model of passive smoking was prepared by breeding male rats in a cigarette-smoking box. Bone mineral content (BMC), bone mineral density (BMD), bone turnover markers, bone histomorphometric parameters and biomechanical properties were examined.Results: Smoke exposure decreased BMC and BMD, increased bone turnover (inhibited bone formation and stimulated its resorption), affected bone histomorphometry (increased trabecular separation and osteoclast surface per bone surface; decreased trabecular bone volume, trabecular thickness, trabecular number, cortical thickness, bone formation rate and osteoblast surface per bone surface), and reduced mechanical properties.EPF supplementation during cigarette smoke exposure prevented smoke-induced changes in bone mineral status and bone turnover.Conclusion: The results suggest that EPF can prevent the adverse effects of smoke exposure on bone by stimulating bone formation and inhibiting bone turnover and bone resorption. [ABSTRACT FROM AUTHOR]

The article reports on research which was conducted to compare the Watson-Jones, Evan and Chrisman-Snook versions of nonanatomic tenodesis reconstruction procedures which are used in lateral ankle ligament reconstruction. They found that the that the Watson-Jones procedure has advantages with regard to anterior and rotational stabilities as well as ligaments and grafts stresses in comparison with other nonanatomic tenodesis reconstruction methods.

Background: Many studies have identified smoking as a risk factor for osteoporosis, but it is unclear whether passive smoking has an effect on bone mineral density and bone turnover and if such an effect could cause osteoporosis.The purpose of the study was to investigate the effect of passive smoking on bone mineral density (BMD) and bone turnover and the relationship between BMD and bone turnover in female rat. Methods: Forty-eight female Wistar rats were randomized into six groups: 2-month, 3-month,4-month smokeexposed rats and their controls. A rat model of passive cigarette smoking was prepared by breeding female rats in a cigarette-smoking box for 2, 3 or 4 months. Serums were analyzed for levels of osteocalcin, bone-specific alkaline phosphatase (b-ALP) and Tartrate-resistant acid phosphatase 5b (TRACP 5b). BMD was assessed at lumbar vertebrae and femur by dual energy X-ray absorptiometry in passive smoking rats and in control rats. Results: BMD of lumbar spine and femur was lower in 4-month smoke-exposed female rats than that in controls. However, there was no significant difference in serum osteocalcin levels between smoke-exposed rats and controls. Significantly lower b-ALP and higher TRACP 5b were found in the 3-month or 4-month smoke-exposed rats compared to controls. Subsequent analysis showed that b-ALP positively correlated with BMD of the lumbar vertebrae(r = 0.764, P = 0.027) and femur(r = 0.899, P = 0.002) in 4-month smoke-exposed female rats. Furthermore, TRACP 5b levels negatively correlated with BMD of lumbar vertebrae (r = -0.871, P = 0.005) and femur (r = -0.715, P = 0.046) in 4-month smoke-exposed female rats. Conclusion: Our data suggest that smoke exposure can inhibit bone formation and increase bone resorption. The hazardous effects of passive smoking on bone status are associated with increased bone turnover in female rat. [ABSTRACT FROM AUTHOR]

Objective: To explore the underlying mechanism of mesenchymal stem cells (MSCs) transfer induced cardiac function improvement in failing hearts., Methods: Congestive heart failure (CHF) was induced in rats by cauterization of the heart wall. MSCs were cultured from autologous bone marrow and injected into the border zone and the remote myocardium 5 days after cauterization., Results: Ten weeks later, cardiomyocyte nucleus mitotic index, capillary density and expression of insulin-like growth factor 1 (IGF-1), hepatocyte growth factor (HGF) and vascular endothelial growth factor (VEGF) were significantly increased in the border zone and significantly reduced in the remote myocardium in CHF rats (all P<0.05 vs. sham). Besides cardiac function improvement and left ventricular remodeling attenuation evidenced by hemodynamic and echocardiographic examinations, expressions of IGF-1, HGF and VEGF in the remote myocardium and in the border zone were also significantly upregulated (P<0.05 or P<0.01 vs. CHF), and cardiomyocyte nucleus mitotic index as well as capillary density were significantly increased in CHF rats with MSCs (P<0.05 or P<0.01 vs. CHF). Moreover, collagen area was significantly reduced and myocardial area was significantly increased in the border zone in these rats too., Conclusion: Autologous MSC implantation upregulated expressions of growth factors enhanced cardioangiogenesis which might be the underlying mechanisms for improved cardiac function and attenuated left ventricular remodeling induced by MSCs transplantation in failing rat myocardium.

Objective: To explore the relationship between human umbilical vascular endothelial cells (HUVECs) and endothelial lipase (EL), and the effect of EL on expression of endothelial cell adhesion molecule (ICAM)., Methods: HUVECs was treated with tumor necrosis factor-alpha(TNF-alpha) 10 microg/L and the mRNA of adhesion molecules [intercellular adhesion molecule-1 (ICAM-1), vascular cellular adhesion molecule-1 (VCAM-1) and E-selectin] were detected by reverse transcription-polymerase chain reaction (RT-PCR). Then the effect of 50 microg/L anti-endothelial lipase (anti-EL) antibody on the influence of TNF-alpha on these adhesion molecules was observed., Results: After being treated with TNF-alpha, the mRNA of adhesion molecules expressed by HUVECs were significant up-regulated, there was significant difference compared with control group (all P<0.01). These effects of TNF-alpha were significantly abolished by 50 microg/L anti-EL antibody (P<0.05 or P<0.01)., Conclusion: EL can affect the expression of adhesion molecules on endothelial cell adhesion molecule. This effect of EL may play a role in the pathophysiologic process in the pathogenesis progress of atherosclerosis.