Neuroprotective effect of rapamycin on spinal cord injury via activation of the Wnt/β-catenin signaling pathway

The Wnt/β-catenin signaling pathway plays a crucial role in neural development, axonal guid- ance, neuropathic pain remission and neuronal survival. In this study, we initially examined the effect of rapamycin on the Wnt/β-catenin signaling pathway after spinal cord iniury, by intraperitoneally injecting spinal cord injured rats with rapamycin over 2 days. Western blot analysis and immunofluorescence staining were used to detect the expression levels of β-catenin protein, caspase-3 protein and brain-derived neurotrophic factor protein, components of the Wnt/β-catenin signaling pathway. Rapamycin increased the levels of β-catenin and brain-derived neurotrophic factor in the injured spinal cord, improved the pathological morphology at the injury site, reduced the loss of motor neurons, and promoted motor functional recovery in rats after spinal cord injury. Our experimental fndings suggest that the neuroprotective effect of rapamycin intervention is mediated through activation of the Wnt/β-catenin signaling pathway after spinal cord injury.

Using posterior part of the deltoid muscle as receptor and quality control with intra-operative electrophysiological examination in targeted muscle reinnervation for high-level upper extremity amputees

To the Editor:Targeted muscle reinnervation(TMR)is a surgical technique of multiple nerve transfers,providing a potential of improved intuitive prosthetic control via surface electromyography(sEMG)in the high-level upper extremity amputees.[1]However,there is a risk that some of the reinnervations might be unsuccessful,especially for the ulnar nerve.[2]Both the quality control of nerve stumps and the receptor are important factors for the surgery.Assessing the nerve stumps during the surgery and finding more muscles as receptor might address the problem.Biceps,triceps,and brachialis muscles were mostly chosen as receptors for reinnervation in the trans-humeral amputees.Pectoralis major and pectoralis minor were mostly chosen as receptors for reinnervation in the shoulder disarticulation patients.