Motor and sensitive recovery after injection of a physically cross-linked PNIPAAm-g-PEG hydrogel in rat hemisectioned spinal cord

Publication date: Available online 23 October 2019Source: Materials Science and Engineering: CAuthor(s): Maxime Bonnet, Thomas Trimaille, Brezun Jean-Michel, François Feron, Didier Gigmes, Tanguy Marqueste, Patrick DecherchiAbstractIn line with experiments showing that implanted hydrogels are promising tools, we designed and injected, after a C2 spinal cord hemisection, a thermoresponsive and thermoreversible physically cross-linked poly(N-isopropylacrylamide)-poly(ethylene glycol) copolymer in order to reduce functional deficits and provide a favorable environment to axotomized axons.Nasal olfactory ecto-mesenchymal stem cells were cultured on the hydrogel in order to verify its biocompatibility. Then, inflammatory reaction (Interleukin-1β and 6, Tumor Necrosis Factor-α) was examined 15 days post-hydrogel injection. Functional recovery (postural and locomotor activities, muscle strength and tactile sensitivity) was assessed once a week, during 12 weeks. Finally, at 12 weeks post-injection, spinal reflexivity and ventilatory adjustments were measured, and the presence of glial cells and regenerated axons were determined in the injured area.Our results indicate that cells survived and proliferated on the hydrogel which, itself, did not induce an enhanced inflammation. Furthermore, we observed significant motor and sensitive improvements in hydrogel-injected animals. Hydrogel also induced H-reflex recovery close to control animals but no improved ventilatory a...
Source: Materials Science and Engineering: C - Category: Materials Science Source Type: research

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Source: Journal of Neuroinflammation - Category: Neurology Authors: Tags: Research Source Type: research
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Source: Seminars in Neurology - Category: Neurology Authors: Tags: Review Article Source Type: research
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Source: Seminars in Neurology - Category: Neurology Authors: Tags: Review Article Source Type: research
Conclusion: VR (a measure of cardiovagal function) and TR (a measure of sympathetic adrenergic function) are reliable quantitative parameters that can be derived from SBP response to VM in participants with SCI. Qualitative waveform analysis was reproducible in 12/14 participants. This provides the foundational evidence required to pursue further validity testing to establish a role for VM in the assessment of autonomic functions in SCI. PMID: 32795170 [PubMed - as supplied by publisher]
Source: Journal of Spinal Cord Medicine - Category: Orthopaedics Tags: J Spinal Cord Med Source Type: research
Conclusions Late recovery of the bulbocavernosus reflex in the postoperative period may be associated with poorer neurological and functional outcome for individuals sustaining a motor-complete traumatic spinal cord injury, for which the prognosis estimation is limited. A prospective study including a larger number of patients is necessary to confirm results of this study.
Source: American Journal of Physical Medicine and Rehabilitation - Category: Rehabilitation Tags: Original Research Articles Source Type: research
This article is protected by copyright. All rights reserved. PMID: 32721039 [PubMed - as supplied by publisher]
Source: The Journal of Physiology - Category: Physiology Authors: Tags: J Physiol Source Type: research
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Source: Experimental Neurology - Category: Neurology Authors: Tags: Exp Neurol Source Type: research
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Source: Frontiers in Physiology - Category: Physiology Source Type: research
Authors: Pearce JMS Abstract François Pourfour du Petit was a Parisian experimental neuro-anatomist, and ophthalmologist, who investigated his extensive wartime experiences of brain and spinal injuries and verified his conclusions by animal experiments. His results showed with great originality that brain injuries caused weakness or paralysis of the opposite limbs. He also clarified the anatomy of the spinal cord and decussation of the pyramidal tracts, and demonstrated the anatomy and clinical significance of the cervical sympathetic chain. PMID: 32654778 [PubMed - as supplied by publisher]
Source: Revue Neurologique - Category: Neurology Tags: Rev Neurol (Paris) Source Type: research
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Source: Experimental Neurology - Category: Neurology Authors: Tags: Exp Neurol Source Type: research
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