RESUMO
Previous studies have shown that neurofilament protein M expression is upregulated in the early stage of spinal cord ischemia/reperfusion injury, indicating that this protein may play a role in the injury process. In the present study, we compared protein expression in spinal cord tissue of rabbits after 25 minutes of ischemia followed by 0, 12, 24, or 48 hours of reperfusion with that of sham operated rabbits, using proteomic two-dimensional gel electrophoresis and mass spectrometry. In addition, the nerve repair-related neurofilament protein M with the unregulated expression was detected with immunohistochemistry and western blot analysis. Two-dimensional gel electrophoresis and mass spectrometry showed that, compared with the sham group, upregulation of protein expression was most significant in the spinal cords of rabbits that had undergone ischemia and 24 hours of reperfusion. Immunohistochemical analysis revealed that neurofilament protein M was located in the membrane and cytoplasm of neuronal soma and axons at each time point after injury. Western blot analysis showed that neurofilament protein M expression increased with reperfusion time until it peaked at 24 hours and returned to baseline level after 48 hours. Furthermore, neurofilament protein M is phosphorylated under oxidative stress, and expression changes were parallel for the phosphorylated and non-phosphorylated forms. Neurofilament protein M plays an important role in spinal cord ischemia/reperfusion injury, and its functions are achieved through oxidative phosphorylation.
RESUMO
New Zealand rabbits were randomly divided into an ischemia group (occlusion of the abdominal aorta for 60 minutes), an ischemia-reperfusion group (occlusion of the abdominal aorta for 60 minutes followed by 48 hours of reperfusion) and a sham-surgery group. Two-dimensional gel electrophoresis detected 49 differentially expressed proteins in spinal cord tissue from the ischemia and ischemia/ reperfusion groups and 23 of them were identified by mass spectrometry. In the ischemia group, the expression of eight proteins was up regulated, and that of the remaining four proteins was down regulated. In the ischemia/reperfusion group, the expression of four proteins was up regulated, and that of two proteins was down regulated. In the sham-surgery group, only one protein was detected. In the ischemia and ischemia/reperfusion groups, four proteins overlapped between groups with the same differential expression, including three that were up regulated and one down regulated. These proteins were related to energy metabolism, cell defense, inflammatory mechanism and cell signaling.
RESUMO
OBJECTIVE: To compare the efficiency of secondary total hip arthroplasty (THA) for osteonecrosis of the femoral head (ONFH) after failed internal fixation of femoral neck fracture and the primary THA for non-traumatic ONFH and to evaluate if the two groups have significant difference. METHODS: From June 2004 to July 2007, 203 cases of ONFH were treated by THA. In group A, 83 patients (83 hips) with ONFH after failed internal fixation included 56 males (56 hips) and 27 females (27 hips) with an average age of 58.3 years (range 45-75 years). According to Ficat classification, there were 61 cases at stage III and 22 cases at stage IV. The Harris score was 37.6 +/- 2.0. The disease course was 1-6 years with an average of 2.6 years. In group B, 120 patients (167 hips) with non-traumatic ONFH included 67 males (94 hips) and 53 females (73 hips) with an average age of 52.6 years (range 41-67 years). According to Ficat classification, there were 56 cases (83 hips) at stage III and 64 cases (84 hips) at stage IV. The Harris score was 38.2 +/- 1.0. The disease course was 1.5-5.0 years with an average of 2.6 years. There were no significant differences in general data between two groups (P > 0.05). RESULTS: All 203 cases were followed up for 2 to 5 years (average 3.4 years). There were no significant differences in the operation time of single-hip, the blood loss, the blood transfusion between two groups (P > 0.05). Intraoperative fractures occurred in 4 hips (4.8%) of group A and 2 hips (1.2%) of group B, showing significant difference (P < 0.05). There were no significant differences (P > 0.05) in the incidence of dislocation [3 hips (3.6%) in group A and 1 hip (0.6%) in group B], continuous femoral pain [2 hips (2.4%) in group A and 1 hip (0.6%) in group B] and infection [1 hip (0.6%) in group B] between two groups. There were no significant differences (P > 0.05) in acetabular abduction, anteversion, femoral anteversion, and combined anteversion angles as well as the recovery rate of acetabular rotational center between two groups. The Harris scores of groups A and B after 2 years were 79.4 +/- 2.1 and 84.2 +/- 3.5. There was no significant difference between two groups (P > 0.05). The Harris score postoperation had significant differences compared with preoperation (P < 0.05). CONCLUSION: Compared to the primary THA to non-traumatic ONFH, secondary THA to ONFH after failed internal fixation has no significant increase in operative difficulty, the postoperative hip function is good, but the incidence of intraoperative fracture is higher.