ABSTRACT
Objective To investigate the effects of melatonin on the changes of superoxide dismutase ( SOD ) , reactive oxygen species (ROS),and malondialdehyde(MDA) in N2A cells under hypoxia conditions.Methods Randomly divided the primary cultured neuroblasto-ma cells of mouse into the control group ,hypoxia group ,and MT treatment group .The MT treatment group were given melatonin 5μg/mL for 24 h to set up the treatment model .Rsbiotech of the hypoxia group and MT treatment group were given gaseous mixture of 95%N2 and 5%CO2 ,The ischemia hypoxia model of N 2A cells was set up with cells in the oxidative stress state and cultured for 24 hours at low concentra-tions of serum .The content of SOD , ROS, and MDA was measured respectively by xanthine oxidase , fluorogenic quantitative detection and thiobarbituric acid chromatometry .Results The expression of SOD in hypoxia group and MT treatment group were significantly decreased compared with that in control group(P<0.05).The level of SOD in MT treatment group significantly recovered compared with hypoxia group with singnificant difference (P<0.05).The expression of MDA and ROS in hypoxia group and MT treatment group were significantly in-creased compared with that in control group (P<0.05).The level of MDA and ROS in MT treatment group significantly recovered compared with hypoxia group with singnificant difference (P<0.05).Conclsion Melatonin provides a protective effect on the secondary damage of nerve cells with hypoxia ischemia .The possible mechanism is melatonin could play the role of free radical scavenging and up -regulate the ex-pression level of antioxidants .
ABSTRACT
BACKGROUND:Three-dimensional visualization technique has been widely used in clinical treatment. Preoperative visualization technique al ows safe demonstration on the complex spine fracture models, and also prepare screw placement scheme according to three-dimensional model of patients. OBJECTIVE:To discuss the clinical result of treating short-segment lumbar vertebrae fracture with pedicle screw visualization. METHODS:A total of 32 patients with lumbar vertebrae fracture were treated with 182 pedicle screws. Before the screw implantation, the structure of bilateral pedicle was observed using Mimics software and the implantation parameters were measured. The operation methods and related complications were told to the patients through the reconstructed three-dimensional images. The satisfaction of the patients, operation time, and the position of pedicle screws by postoperative CT scan were assessed. The percentages of anterior vertebral height and Cobb’s angle were measured before operation, 2 weeks after operation and 8 months after operation. RESULTS AND CONCLUSION:The excellent satisfaction rate of the patients was 100%, the mean operation time was 185 minutes, and 173 pedicle screws (95.1%) were total y inserted within the pedicle. Al patients were fol owed up for 7-22 months. The results showed that the fracture healed wel . The percent of anterior vertebral height and Cobb’s angle at 2 weeks after operation were significantly decreased compared with them before operation (P0.05). Single-segment lumbar vertebrae fracture was wel treated by the pedicle screw visualization technique. This method assists to make up preoperation plan, increase the rate of patients’ satisfaction, shorten operation time, and increase the accuracy of pedicle screw insertion.