Objective: To investigate the effect of adiponectin levels with its related mechanism in diabetic myocardial ischemia-reperfusion injury and ischemia post-conditioning in experimental rats. Methods: A total of 80 male SD rats were randomly divided into 6 groups: Normal sham (NS) group,n=8, Normal ischemia-reperfusion injury (NIRI) group,n=16, Normal ischemia post-conditioning (NIPO) group,n=16 and Diabetic mellitus sham (DMS) group,n=8, Diabetic mellitus ischemia-reperfusion injury (DMIRI) group,n=16, Diabetic mellitus ischemic post-conditioning (DMIPO) group,n=16. DM rats model was established by intraperitoneal injection of streptozotocin; IR model was established by occlusion of left anterior descending (LAD) coronary artery for 30 min followed by reperfusion for 120min; IPO model was established by 3 cycles of ischemia for 10s and reperfusion for10s; the rats in Sham group received silk line wrapping of LAD without occlusion. The myocardial infarction (MI) area was measured by TTC staining, plasma adiponectin level was examined by ELISA, the protein expressions of p-Akt and total-Akt were detected by Western blot analysis. Results: Compared with NIRI group, NIPO group had decreased MI area,P<0.05, while DMIRI group and DMIPO group had increased MI area,P<0.01; compared with NS group, NIRI group and NIPO group showed up-regulated expression of adiponectin and p-Akt,P<0.05 and DMS group showed down-regulated p-Akt,P<0.05. Compared with NIPO group, three DM groups presented down-regulated adiponectin and p-Akt,P<0.05. Linear correlation analysis indicated that plasma adiponectin expression level was negatively related to MI area and positively related to myocardial tissue p-Akt expression with the correlation coefifcient at 0.63 and 0.65 respectively, P<0.01. Conclusion: Down-regulated plasma adiponectin expression may cause the inactivation of PI3K/Akt signal pathway and therefore aggravate DM ischemia-reperfusion injury which cannot be protected by ischemic post-conditioning in experimental rats.

Objective:To explore the epidemiological characteristics, clinical characteristics, treatment strategies and clinical results of non-dislocated hyperextension tibial plateau fracture.Methods:A total of 25 cases of non-dislocated hyperextension tibial plateau fracture patients were collected, including 12 males and 13 females, aged 27-79 years with an average age of 51±15 years. Causes of injury: 18 cases of traffic accident, 2 cases of heavy injury, 5 cases of falling injury. Schatzker classification of tibial plateau fracture: 4 cases of type II, 5 cases of type IV, 13 cases of type V, 3 cases of type VI. Three columns theoretical classification: 4 cases of simple lateral column, 5 cases of simple medial column, 7 cases of medial column+lateral columns, 9 cases of three columns. Preoperative tibial plateau posterior slope angle was -10-0 degrees, average-5.2 degrees. Preoperative MRI showed 5 cases of medial collateral ligament (MCL) injury, 3 cases of posterolateral complex (PLC) complex injury, 2 cases of PLC+ posterior cruciate ligament (PCL) injury and 10 cases of menisci injury. The change of tibial plateau posterior slope angle was more than 10 degrees in patients with ligament injury, 5 patients had a tibial plateau posterior slope angle change more than 15 degrees, 5 patients had a tibial plateau posterior slope angle change more than 10 degrees, and the patients with a tibial plateau posterior slope angle change less than 10 degrees had no ligament injury; 6 patients with simple lateral column or medial column fracture had a ligament injury, 2 patients with medial column+lateral column fracture had a ligament injury, and 2 patients with three column fracture had a ligament injury.Results:All patients were followed up for 12-24 months, with an average of 16.4 months. The operation time was 124±33 min (65-180 min), and the bleeding volume was 106±48 ml (20-200 ml). All patients were treated by open reduction and internal fixation. According to the characteristics of fracture, targeted reduction of articular surface and restoration of lower limb force line were carried out. The plate was placed on the anterior part of tibial plateau to fix the fracture fragment. Evaluation of postoperative fracture reduction: 20 cases were anatomic reduction, 5 cases were good reduction (between 2-5 mm articular surface collapse), and the excellent rate of fracture reduction was 100%. Internal fixation: 4 cases were treated with simple lateral plate, 2 cases with simple medial plate, 15 cases with medial+ lateral plate, 1 case with medial plate+ lateral anchor suture, 1 case with medial plate+ posterior screw, 1 case with lateral plate+ fibular screw, 1 case with medial plate + lateral plate+ lateral anchor suture. The meniscus was repaired in 8 patients, including 5 medial and 3 laterals. The fracture healing time was 3-6 months (mean 3.3 months). The postoperative knee Rasmussen score was 24.9±3.5 (18-29), and the postoperative knee joint mobility was 118°±9° (90°-130°). Superficial infection occurred in 2 patients.Conclusion:The main imaging characteristic of "non-dislocated hyperextension tibial plateau fracture" is the change of tibial plateau posterior slope angle. The injury of single anteromedial column/anterolateral column fracture is easy to combine with the "diagonal" injury, and when the tibial plateau posterior slope angle changes more than 10 degrees, it is easy to be associated with peripheral ligament injury. By using open reduction and internal fixation, restoring the joint articular surface and lower limb force line, repairing the soft tissue structure and ligament, and reconstructing the stability of knee joint, we can achieve satisfactory results.