Objective:To study the effect of the cyclic-tension force on the expression of matrix metalloproteinase-3 ( MMP-3) mRNA in osteoclasts. Methods: Bone marrow cells were cultured and induced by the combination of IL-6 and 1,25(OH) 2D 3 and identified. The bone marrow cells were seeded onto elastic 6-well culture plate at a density of 2?105 cells/ml in 2ml in each well and cultured for 7 days. Then the cells were subjected to 12% elongation by a strain unit at 6 cycles/min (i.e.5-s elongation and 5-s relaxation) . After 24 hours of stretching, the expression of MMP-3 mRNA in osteoclasts were determined by in situ hybridization analysis. Results:The stretched osteoclasts showed enhanced MMP-3 mRNA expression level. Conclusion: The mechanical stretching may affect the bone-resorbing activity by up-regulated the expression of MMP-3 mRNA in osteoclasts.

Objective To investigate the chronic renal failure (CRF) patients with serum hyaluronic acid (HA),procollagen type Ⅲ (PC-Ⅲ),collagen type Ⅳ (C-Ⅳ) and laminin (LN) joint detection of clinical significance.Methods Using chemiluminescence method in 80 cases of CRF patients (CRF group) and 60 healthy (control group) serum HA,PC-Ⅲ,C-Ⅳ and LN for joint detection and comparison.Results The serum HA,PC-Ⅲ,C-Ⅳ in CRF group was significantly higher than that in control group [(305.37 ± 41.28) μ g/L vs.(73.26 ± 21.21) μ g/L,(236.39 ± 56.63) μ g/L vs.(68.46 ± 32.55) μtg/L,(112.54 ±26.73) μg/L vs.(55.36 ± 18.44) μg/L] (P ＜0.01).The LN there was no statistically significant difference between two groups (P ＞ 0.05).Conclusion Detecting HA,PC-Ⅲ,C-Ⅳ for the early diagnosis and therapeutic efficacy observation of patients with CRF has important clinical significance.