OBJECTIVE:To investigate the influences of Schwann cells-alginic acid sodium hydrogel transplantation on cellular apoptosis,Bcl-2 expression,and lower limb locomotor function in a rat model of spinal cord injury.METHODS:SD rats of clean grade were randomly divided into 4 groups:normal control,simple injury,Schwann cells,and Schwann cells-alginic acid sodium hydrogel.Spinal cord transaction model was established in the latter 3 groups.Gelatin sponge blocks containing Schwann cells suspension were transplanted into the Schwann cells group.Schwann cells-alginic acid sodium hydrogel was transplanted into Schwann cells-alginic acid sodium hydrogel group.No treatments were performed in the normal control and simple injury groups.At 12 hours,1,3,7,and 21 days after surgery,animals were assessed using Basso,Beattie and Bresnahan (BBB) locomotor rating scale and were sacrificed.The spinal cord-transected segments were taken to prepare paraffin sections for TUNEL and Bcl-2 staining to quantitate apoptotic cells and Bcl-2 cells in the injured spinal cord and to investigate their distributions.RESULTS:A small number of slightly stained Bcl-2 positive cells were observed in the normal control group.In the simple injury group,Bcl-2 immunoreactive cells peaked at 3 days after surgery,and the expression level was close to normal level at 14 days.Following Schwann cells-alginic acid sodium hydrogel transplantation,Bcl-2 immunoreactive cells in the spinal cord-transected segments were significantly increased till 7 days (P＜0.05) and remained this level for more than 14 days.In the simple injury group,apoptotic cells were most as compared with the remaining 3 groups,and peaked at 1 and 7 days following spinal cord injury,and they were mostly distributed in the white matter.BBB scores were significantly higher in the Schwann cells-alginic acid sodium hydrogel transplantation group than in the simple injury and Schwann cells groups (P＜0.05).CONCLUSION:Schwann cells-alginic acid sodium hydrogel transplantation could inhibit cellular apoptosis and enhance Bcl-2 expression in the spinal cord-transected segments,and thereby promote the recovery of locomotor function after spinal cord injury but did not reach normal levels.

Objective: To study the effects of the palatal spur and chincup in the early treatment of anterior open bite in patients with Angle class Ⅰ malocclusion. Methods: Electronic search was conducted to find studies about the effects of the palatal spur and chincup in the early treatment of anterior open bite in patients with Angle class Ⅰ malocclusion. Data extraction and risk of bias assessment of included studies were conducted. RevMan5. 3 software was used fore Meta-analysis. Results: 6 clinical trials were qualified to the Meta-analysis. Compared to the control group, there was no significant change of skeletal measurments after treatment (P＞ 0. 05), and no significant change in dental measurments in chincup group (P＞ 0. 05) . While overbite, U1-PP (mm) and L1-MP (mm) were increased (P ＜ 0. 05), U1-NA (°) and L1-NB (°) decreased (P ＜ 0. 05) in the 3 groups of fixed palatal crib, bonded spur associated with the chincup and the removable palatal spur associated with the chincup. Conclusion: Chincup is not effective in the early treatment of the anterior open bite in patients with Angle class I malocclusion. But chincup combined with palatal spur or crib and have a positive effect on the closure of open bite through the palatal clination and extraction of the anterior teeth without influence of molar intrusion and skeletal change.