Time course of calpain activity changes in rat neurons following fluid percussion injury and the interventional effect of mild hypothermia / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the time course of calpain activity changes in rat neurons following fluid percussion injury (FPI) under normothermia (37 degrees celsius;) and mild hypothermia (32-/+0.5) degrees celsius;.</p><p><b>METHODS</b>In vitro cultured rat neurons were subjected to FPI followed by application of mild hypothermia for intervention at different time points, and the changes in intraneuronal calpain activity following FPI and the interventional effect of mild hypothermia on calpain activity were evaluated by UV-spectrophotometry at different time points.</p><p><b>RESULTS</b>Remarkable changes occurred in calpain activity in the neurons following FPI at 37 degrees celsius;, and mild hypothermia produced obvious interventional effect on calpain activity in close relation to the timing of intervention initiation.</p><p><b>CONCLUSION</b>Intraneuronal calpain activity changes following FPI are involved in the pathological process of cellular injury, and mild hypothermia might offer protection against traumatic brain injury to some extent by regulating calpain activity. The interventional effect of mild hypothermia is associated with the timing of the intervention initiation.</p>

Human neural stem cells promote corticospinal axons regeneration and synapse reformation in injured spinal cord of rats / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Axonal regeneration in lesioned mammalian central nervous system is abortive, and this causes permanent disabilities in individuals with spinal cord injuries. This paper studied the action of neural stem cell (NSC) in promoting corticospinal axons regeneration and synapse reformation in rats with injured spinal cord.</p><p><b>METHODS</b>NSCs were isolated from the cortical tissue of spontaneous aborted human fetuses in accordance with the ethical request. The cells were discarded from the NSC culture to acquire NSC-conditioned medium. Sixty adult Wistar rats were randomly divided into four groups (n = 15 in each): NSC graft, NSC medium, graft control and medium control groups. Microsurgical transection of the spinal cord was performed in all the rats at the T11. The NSC graft group received stereotaxic injections of NSCs suspension into both the spinal cord stumps immediately after transection; graft control group received DMEM injection. In NSC medium group, NSC-conditioned medium was administered into the spinal cord every week; NSC culture medium was administered to the medium control group. Hindlimb motor function was assessed using the BBB Locomotor Rating Scale. Regeneration of biotin dextran amine (BDA) labeled corticospinal tract was assessed. Differentiation of NSCs and the expression of synaptophysin at the distal end of the injured spinal cord were observed under a confocal microscope. Group comparisons of behavioral data were analyzed with ANOVA.</p><p><b>RESULTS</b>NSCs transplantation resulted in extensive growth of corticospinal axons and locomotor recovery in adult rats after complete spinal cord transection, the mean BBB scores reached 12.5 in NSC graft group and 2.5 in graft control group (P < 0.05). There was also significant difference in BBB score between the NSC medium (11.7) and medium control groups (3.7, P < 0.05). BDA traces regenerated fibers sprouted across the lesion site and entered the caudal part of the spinal cord. Synaptophysin expression colocalized with BDA positive axons and neurons distal to the injury site. Transplanted cells were found to migrate into the lesion, but not scatter along the route of axon grows. The cells differentiated into astrocytes or oligodendrocytes, but not into the neurons after transplantation. Furthermore, NSC medium administration did not limit the degree of axon sprouting and functional recovery of the injured rats compared to the NSC graft group.</p><p><b>CONCLUSIONS</b>Human embryonic neural stem cells can promote functional corticospinal axons regeneration and synapse reformation in the injured spinal cord of rats. The action is mainly through the nutritional effect of the stem cells on the spinal cord.</p>

Effect of combined therapy of mild hypothermia and hibernation on severe brain injury / 中国康复理论与实践

@#ObjectiveTo investigate the efficacy of combined therapy of mild hypothermia and hibernation to treat severe brain injury. Methods24 patients with severe brain injury were randomly divided into combined therapy group and normothermia group. Glasgow Coma Scale scores of all the patients were in the range of 3 to 8. No later than 10 hours after their injury, hypothermia patients were given half dosage of No.1 hibernation cocktail and had been cooled by cooling blankets to 32℃-34℃ (rectal temperature) for 5 days, then to 35℃ for 24 hours, and slowly increased to their normal level. 3 days and 7 days after their admission, intracranial pressure,creatine phosphate kinase,partial pressure of arterial O2 and CO2, platelet and Na+,K+ were measured.7 days after their admission, Glasgow Outcome Scale scores of each patient and mortality of each group were measured. ResultsThe mortality of combined therapy group(25.0%) was significantly lower than that of normothermia group (66.6%,P<0.05). The decreased values of intracranial pressure, creatine phosphate kinase and platelet number of combined therapy group were all significantly higher than that of normothermia group respectively (P<0.05). There were no significant difference in mean artery pressure, blood electrolyte, and partial pressure of arterial O2 and CO2 between these two groups(P>0.05). ConclusionThe combined therapy of mild hypothermia and hibernation can effectively reduce the mortality of patients with severe brain injury as it is much easier, less invasive and with less complications.