Mechanism of Cxc Chemokine Ligand 5 (CXCL5)/Cxc Chemokine Receptor 2 (CXCR2) Bio-Axis in Mice with Acute Respiratory Distress Syndrome.

BACKGROUND Acute respiratory distress syndrome (ARDS) is a common acute and severe disease in clinic. Recent studies indicated that Cxc chemokine ligand 5 (CXCL5), an inflammatory chemokine, was associated with tumorigenesis. The present study investigated the role of the CXCL5/Cxc chemokine receptor 2 (CXCR2) bio-axis in ARDS, and explored the underlying molecular mechanism. MATERIAL AND METHODS The pathological morphology of lung tissue and degree of pulmonary edema were assessed by hematoxylin-eosin staining and pulmonary edema score, respectively. Real-time PCR and Western blot analysis were performed to detect the expression levels of CXCL5, CXCR2, Matrix metalloproteinases 2 (MMP2), and Matrix metalloproteinases 9 (MMP9) in lung tissues. Enzyme-linked immunosorbent assay (ELISA) was performed to determine the expression levels of CXCL5 and inflammatory factors (IL-1ß, IL-6, TNF-alpha, and IL-10) in serum. RESULTS The results demonstrated that diffuse alveolar damage and pulmonary edema appeared in lipopolysaccharide (LPS)-induced ARDS and were positively correlated with the severity of ARDS. In addition, CXCL5 and its receptor CXCR2 were overexpressed by upregulation of MMP2 and MMP9 in lung tissues of ARDS. In addition, CXCL5 neutralizing antibody effectively alleviated inflammatory response, diffuse alveolar damage, and pulmonary edema, and decreased the expression levels of MMP2 and MMP9 compared to LPS-induced ARDS. CONCLUSIONS We found that CXCL5/CXCR2 accelerated the progression of ARDS, partly by upregulation of MMP2 and MMP9 in lung tissues with the release of inflammatory factors.

[Comparison of the efftec between eccentric fixation and intramedullary fixation for treatment of intertrochanteric fractures].

OBJECTIVE: To compare the efficacy between eccentric fixation and internal fixation for treatment of intertrochanteric fractures of femur,to provide a theoretical basis for the selection of the treatment method of the intertrochanteric fractures of femur. METHODS: From February 2007 to January 2010,82 patients with femoral intertrochanteric fracture were treated by internal fixation including 39 cases of eccentric fixation involving 23 males and 6 females, aged from 41 to 81 years old with an average of (62.68±10.69), using the DHS or proximal femoral locking plate; 43 cases of intramedullary fixation involving 15 males, 28 females,aged from 43 to 78 years old with an average of (62.60±8.37),using PFN or PFNA fixed. The surgical incision length, operative time, blood loss and postoperative Harris score between two groups were compared. RESULTS: The wound of two groups were primary healing without operative complications. All cases received follow-up for an average time of 18.3 months (12 to 28 months). The incision length, operative time and blood loss had a statistically significant difference between two groups (P<0.05). Harris scores of hip joint function at 1 month after operation had statistically significant difference between two groups (P<0.05), and Harris scores at 12 months after operation had no statistical significance difference between two groups. The rate of excellent and good was 89.7% in eccentric fixation group and 90.7% in intramedullary fixation group,the difference was not statistically significant (t=0.0613, P>0.05). In eccentric fixation group, there was 1 case of fracture nonunion with DHS loose and ensuing hip varus deformity. In intramedullary nail fixation group, there was no anti-rotation out,distal intramedullary nail of femoral refracture occurred in 1 case. CONCLUSION: Two treatment methods for the treatment of femoral fractures had a good therapeutic effect,but the intramedullary fixation had shorter operative time and less blood loss than the eccentric fixation,it prior to apply to osteoporosis and unstable femoral intertrochanteric fractures.