Sciatic Nerve Regeneration through Venous or Nervous Grafts in the Rat

in Experimental Neurology (1997), 148(1), 236-46

This study analyses the interest of isologous venous grafts filled with saline or with Schwann cells versus nerve grafts as guides for regeneration of the sciatic nerve in 35 Wistar rats ... [more ▼]

This study analyses the interest of isologous venous grafts filled with saline or with Schwann cells versus nerve grafts as guides for regeneration of the sciatic nerve in 35 Wistar rats. Electrophysiological parameters (conduction velocities and distal latencies of motor responses) and the functional index of De Medinacelli were measured several times from 1 month to 1 year after surgery. An histological analysis was performed on 2 control rats and on 3 rats killed 6 or 12 months after surgery: the total number of fibers was counted on a montage photoprint of the whole nerve, and the diameters of axons and the thickness of the myelin sheath were measured on digitized images. With a portion of nerve as guide, the regeneration is faster than with a vein. However, regeneration after 6 months is at least as good with a venous graft filled with Schwann cells, as assessed by electrophysiological, functional, and histological analysis. The addition of Schwann cells in grafted veins allows the nerve to regenerate through longer gaps than previously described (25 vs 15 mm). In order to assess the quality of nerve regeneration, functional, electrophysiological, and histological analysis are complementary. [less ▲]

Preparation of a Macroporous Biodegradable Polylactide Implant for Neuronal Transplantation

in Journal of Biomedical Materials Research (1995), 29(11), 1349-62

This article reports the production of a surgical implant meeting several specific requirements such as biocompatibility, biodegradability, macroporosity, and flexibility. Porosity was controlled by an ... [more ▼]

This article reports the production of a surgical implant meeting several specific requirements such as biocompatibility, biodegradability, macroporosity, and flexibility. Porosity was controlled by an original method consisting of the aggregation of calibrated poly-D,L-lactide microparticles. The size of the interstices between the aggregated microspheres was in a direct relationship to the microsphere diameter. A first approach was based on coating the microspheres with poly(vinyl alcohol) followed by chemically crosslinking the coating layers that were in mutual contact. This method was disregarded because of the acute cytotoxicity of glutaraldehyde used as the crosslinking agent, the absence of macroporosity, and the complete lack of flexibility. A physical technique of aggregation was then tested, which relied on the plasticization of poly-D,L-lactide microspheres with triethylcitrate to the point where microspheres strongly adhered to each other when they were in contact. This method has proved to be straightforward and definitely superior to the chemical approach, particularly with respect to cytotoxicity, control of macroporosity, and flexibility. A polymer support was thus successfully which was biodegradable, macroporous( interconnected pores of 10-100 microns in diameter), and flexible. This potential medical device is presently being used for neuronal transplantation in the central nervous system. [less ▲]

Acute myocardial infarction in a young female migraineur: sumatriptan suspected, but found not guilty.

in Cephalalgia : An International Journal of Headache (1994), 14(4), 305

Transplants of syngenic cultured, DRG-derived Schwann cells into the injured adult rat spinal cord.

Conference (1993, June 18)

Manufacture of a macroporous biocompatible and biodegradable surgical implant, allowing neurons and Schwann cells culture, before their transplantation in the central nervous system

Conference (1993, March 23)

Syngeneic Grafting of Adult Rat Drg-Derived Schwann Cells to the Injured Spinal Cord

in Brain Research Bulletin (1993), 30(3-4), 507-14

A subdural inflatable micro-balloon was used to induce closed traumatic contusion to adult rat spinal cord. This spinal cord injury model was associated with reproducible and graded neurological deficits ... [more ▼]

A subdural inflatable micro-balloon was used to induce closed traumatic contusion to adult rat spinal cord. This spinal cord injury model was associated with reproducible and graded neurological deficits and histopathological alterations. At various delays after injury, transplantations of syngeneic adult cultured dorsal root ganglion-derived Schwann cells were performed into the spinal cord lesion. The transplants were well integrated and reduced the microcystic posttraumatic cavitation as well as the gliosis. Schwann cells transplants were invaded by numerous regenerating neurites most of which, based upon their neurotransmitter contents, seem to originate from the dorsal root ganglion. [less ▲]

Neurotransmitter phenotype plasticity in adult dorsal root ganglia neurons

in Restorative Neurology & Neuroscience (1993), 5

Experimental Acute Traumatic Injury of the Adult Rat Spinal Cord by a Subdural Inflatable Balloon: Methodology, Behavioral Analysis, and Histopathology

in Journal of Neuroscience Research (1992), 32(4), 539-50

We describe an experimental model to produce closed traumatic injuries to the spinal cord of adult rats. This model uses an inflatable balloon that is introduced in the dorsal subdural space and moved to ... [more ▼]

We describe an experimental model to produce closed traumatic injuries to the spinal cord of adult rats. This model uses an inflatable balloon that is introduced in the dorsal subdural space and moved to a location rostral to the laminectomy site. The spinal cord trauma can be graded by varying either the duration of compression or the volume of saline used to inflate the balloon. The locomotor deficit of animals with various degrees of injury has been assessed at increasing delays after trauma. The parameters generating transient or definitive deficits of varying intensity were defined. Some injured animals underwent nuclear magnetic resonance imaging. Detailed histopathological studies demonstrated that the extent of the spinal lesion was significantly correlated with the physical parameters of compression and with the severity of the behavioral deficit. [less ▲]

Mécanismes de communication cellulaire dans le système nerveux périphérique en régénération

in Revue Médicale de Liège (1992), 47(3), 115-8

Plasticité des neurones sensoriels primaires chez le rat adulte. Etude in vitro et in vivo.

Conference (1991, November 16)