Peripheral nerve injuries represent one of the most common causes of permanent disabilities. Therapeutic electrical stimulation has been widely used in neural regeneration for decades. Combined with the implantation of a nerve cuff, several outcomes have proven effectiveness and feasibility in neuroprosthetic applications. However, the current electrical stimulation strategy fails to complete nerve repair. There is a lack of research on long‐term implantable nanogenerators in the neurostimulation scenario. Especially considering many disease models, those devices may not reach the in vitro simulative working setting. Thus, an implanted sciatic nerve stimulation system that spontaneously generates biphasic electric pulses in response to rats’ movement is developed. The electric signals generated by this device could stimulate injured sciatic nerve by cuff electrode. This work introduces an implantable self‐regulated neural electrical stimulation system generated by a contact separation triboelectric nanogenerator with a nerve cuff electrode and compares it with chronic therapeutic electrical stimulation for sciatic nerve restoration effect. Neural function restoration is observed in gait and histological analysis. Moreover, the upregulation of growth associated protein 43 can be a protentional target. This could have potential clinical application in facilitating closed‐loop energy harvesting for long‐term electrical stimulation.

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Although plenty of evidences from preclinical studies have led to potential treatments for patients with spinal cord injury (SCI), the failure to translate promising preclinical findings into clinical advances has long puzzled researchers. Thus, a more reliable combination of anatomical assessment and behavioral testing is urgently needed to improve the translational worth of preclinical studies. To address this issue, the present study was designed to relate magnetic resonance imaging (MRI)-based anatomical assessment to behavioral outcome in a rat contusion model. Rats underwent contusion with three different heights to simulate various severities of SCI, and their locomotive functions were evaluated by the grid-walking test, Louisville swim scale (LSS), especially catwalk gait analysis system and basic testing, and Basso, Beattie, Bresnahan (BBB) score. The results showed that the lesion area (LA) is a better indicator for damage assessment compared with other parameters in sagittal T2-weighted MRI (T2WI). Although two samples are marked as outliers by the box plot analysis, LA correlated closely with all of the behavioral testing without ceiling effect and floor effect. Moreover, with a moderate severity of SCI in a contusion height of 25 mm, the smaller the LA of the spinal cord measured on sagittal T2WI the better the functional performance, the smaller the cavity region and glial scar, the more spared the myelin, the higher the volatility, and the thicker the bladder wall. We found that LA significantly related with behavior outcomes, which indicated that LA could be a proxy of damage assessment. The combination of sagittal T2WI and four types of behavioral testing can be used as a reliable scheme to evaluate the prognosis for preclinical studies of SCI.

Short diffusion time oscillating gradient spin echo (OGSE) showed less water diffusion reduction in acute human stroke lesions (n=28) than the typical clinically used long diffusion time pulsed gradient spin echo (PGSE) method. The diffusion time dependency is far greater in ischemic lesions, particularly white matter, than in contralateral healthy brain. These effects were heterogeneous across the lesion with larger OGSE-PGSE differences in regions indicative of larger axons. The range of MD decrease in lesions across patients as measured with OGSE and PGSE showed a linear correlation and is consistent with concomitant axon beading and swelling implied from prior simulations.