Electrical stimulation of dog pudendal nerve regulates the excitatory pudendal-to-bladder reflex

Pudendal nerve plays an important role in urine storage and voiding.Our hypothesis is that a neuroprosthetic device placed in the pudendal nerve trunk can modulate bladder function after suprasacral spinal cord injury.We had confirmed the inhibitory pudendal-to-bladder reflex by stimulating either the branch or the trunk of the pudendal nerve.This study explored the excitatory pudendal-to-bladder reflex in beagle dogs,with intact or injured spinal cord,by electrical stimulation of the pudendal nerve trunk.The optimal stimulation frequency was approximately 15–25 Hz.This excitatory effect was dependent to some extent on the bladder volume.We conclude that stimulation of the pudendal nerve trunk is a promising method to modulate bladder function.

Effect of low-frequency pulse percutaneous electric stimulation on peripheral nerve injuries at different sites

BACKGROUND： The postoperative recovery of nerve function in patients with peripheral nerve injury is always an important problem to solve after treatment. The electric stimulation induced electromagnetic field can nourish nerve, postpone muscular atrophy, and help the postoperative neuromuscular function. OBJECTIVE： To observe the effects of low-frequency pulse percutaneous electric stimulation on the functional recovery of postoperative patients with peripheral nerve injury, and quantitatively evaluate the results of electromyogram （EMG） examination before and after treatment. DESIGN ： A retrospective case analysis SETTING： The Sixth People＇s Hospital affiliated to Shanghai Jiaotong University PARTICIPANTS： Nineteen postoperative inpatients with peripheral nerve injury were selected from the De- partment of Orthopaedics, the Sixth People＇s Hospital affiliated to Shanghai Jiaotong University from June 2005 to January 2006, including 13 males and 6 females aged 24-62 years with an average of 36 years old. There were 3 cases of brachial plexus nerve injury, 3 of median nerve injury, 7 of radial nerve injury, 3 of ul- nar nerve injury and 3 of common peroneal nerve injury, and all the patients received probing nerve fiber restoration. Their main preoperative manifestations were dennervation, pain in limbs, motor and sensory disturbances. All the 19 patients were informed with the therapeutic program and items for evaluation. METHODS： ① Low-frequency pulse percutaneous electric stimulation apparatus： The patients were given electric stimulation with the TERESA cantata instrument （TERESA-0, Shanghai Teresa Health Technology, Co., Ltd.）. The patients were stimulated with symmetric square waves of 1-111 Hz, and the intensity was 1.2-5.0 mA, and it was gradually adjusted according to the recovered conditions of neural regeneration following the principle that the intensity was strong enough and the patients felt no obvious upset. They were treated for 4- 24 weeks, 10-30 minutes for each time, 1-3 times a day, and 6 weeks as a course. ② EMG examination was applied to evaluate the recoveries of recruitment, motor conduction velocity （MCV） and sensory conduction velocity （SCV） before and after treatment. The patients were examined with the EMG apparatus （DIS- A2000C, Danmark） before and after the treatment of percutaneous electric stimulation. ③Standards for evaluating the effects included cured （complete recovery of motor functions, muscle strength of grade 5, no abnormality in EMG examination）, obviously effective [general recovery of motor function, muscle strength of grade 4, no or a few denervation potentials, motor conduction velocity （MCV） and sensory conduction velocity （SCV）], improved （partial recovery of motor function, muscle strength of grade 3, denervation potentials and reinneration potentials, slowed MCV and SCV, invalid （no obvious changes of motor function）. MAIN OUTCOME MEASURES： ① Ameliorated degree of the nerve function of the postoperative patients with peripheral nerve injury treated with percutaneous electric stimulation; ② Changes of EMG examination before and after treatment. RESULTS： All the 19 postoperative patients with peripheral nerve injury were involved in the analysis of results. ① Comparison of nerve function before and after treatment in 19 patients with peripheral nerve injury of different sites： For the patients with radial nerve injury （n=7）, the nerve functions all completely recovered after 8-week treatment, and the cured and obvious rate was 100% （7/7）; For the patients with brachial plexus nerve injury （n=3）, 1 case had no obvious improvement, and the cured and obvious rate was 67% （2/3）; For the patients with common peroneal nerve injury （n=3）, the extension of foot dorsum generally recovered in 1 case of nerve contusion after 4-week treatment, and the cured and obvious rate was 67% （2/3）; For the patients with median nerve injury （n=3）, muscle strength was obviously recovered, and the cured and obvious rate was 100% （3/3）; For the patients with ulnar nerve injury （n=3）, 1 case only had recovery of partial senses, and the cured and obvious rate was 67% （2/3）. Totally 9 cases were cured, 7 were obviously effective, 1 was improved, and only 2 were invalid. After 4 courses, the cured rate of damaged nerve function after four courses was 47% （9/19）, and effective rate was 89% （17/19）.② Comparison of EMG examination before and after treatment： Before and after percutaneous electric stimulation, he effective rates of recruitment, MCV and SCV were 89% （17/19）, 58% （11/19）, 47% （9/19） respectively, and there were extremely obvious differences （P〈 0.01）. CONCLUSION： ①Low-frequency pulse percutaneous electric stimulation can improve the nerve function of postoperative patients with peripheral nerve injury of different sites, especially that the injuries of radial nerve and median nerve recover more obviously. ②Percutaneous electric stimulation can ameliorate the indexes of EMG examination, especially the recruitment, in postoperative patients with peripheral nerve injury.

Optimising repetitive transcranial magnetic stimulation for neural circuit repair following traumatic brain injury

While it is well-known that neuronal activity promotes plasticity and connectivity, the success of activity-based neural rehabilitation programs remains extremely limited in human clinical experience because they cannot adequately control neuronal excitability and activity within the injured brain in order to induce repair. However, it is possible to non-invasively modulate brain plasticity using brain stimu- lation techniques such as repetitive transcranial （rTMS） and transcranial direct current stimulation （tDCS） techniques, which show promise for repairing injured neural circuits （Henrich-Noack et al., 2013; Lefaucher et al., 2014）. Yet we are far from having full control of these techniques to repair the brain following neurotrauma and need more fundamen- tal research （Ellaway et al., 2014; Lefaucher et al., 2014）. In this perspective we discuss the mechanisms by which rTMS may facilitate neurorehabilitation and propose experimental techniques with which magnetic stimulation may be investi- gated in order to optimise its treatment potential.

Stimulating mitochondria to protect the brain following traumatic brain injury

Traumatic brain injury （TBI） is an acquired injury to the brain that occurs with sudden trauma that can range from mild （concussive） to severe. TBI is considered a leading cause of death in children and young adults, with the Centers for Disease Control and Prevention estimating that approximately 1.7 million cases of TBI occur in the United States annually （Faul et al., 2010）. Further, since the begin- ning of the global war on terrorism, the Department of Defense has reported over 344,000 U.S. Service Members have been diagnosed with traumatic brain injury from penetrating injuries to mild forms of TBI. TBI, caused by a sudden impact, penetration, or rapid move- ment of the brain, interrupts the normal functioning of the brain. While the intracranial location and severity of injury contribute to the extent of functional deficits.

Delayed peripheral nerve repair: methods, including surgical ‘cross-bridging' to promote nerve regeneration

Despite the capacity of Schwann cells to support peripheral nerve regeneration, functional recovery after nerve injuries is frequently poor, especially for proximal injuries that require regenerating axons to grow over long distances to reinnervate distal targets. Nerve transfers, where small fascicles from an adjacent intact nerve are coapted to the nerve stump of a nearby denervated muscle, allow for functional return but at the expense of reduced numbers of innervating nerves. A 1-hour period of 20 Hz electrical nerve stimulation via electrodes proximal to an injury site accelerates axon outgrowth to hasten target reinnervation in rats and humans, even after delayed surgery. A novel strategy of enticing donor axons from an otherwise intact nerve to grow through small nerve grafts（cross-bridges） into a denervated nerve stump, promotes improved axon regeneration after delayed nerve repair. The efficacy of this technique has been demonstrated in a rat model and is now in clinical use in patients undergoing cross-face nerve grafting for facial paralysis. In conclusion, brief electrical stimulation, combined with the surgical technique of promoting the regeneration of some donor axons to ‘protect＇ chronically denervated Schwa nn cells, improves nerve regeneration and, in turn, functional outcomes in the management of peripheral nerve injuries.