[Central and peripheral nervous system motor conduction rate in HIV infection]. / Vitesses de conduction nerveuses motrices centrales et périphériques dans l'infection par le VIH.

In order to assess the central motor pathways of HIV-infected patients motor evoked potentials were recorded on the upper limbs after transcranial and cervical magnetic stimulations and compared with peripheral conduction velocities. Motor evoked potentials were measured on both sides of 28 patients, mostly at the AIDS stage. Our results showed that although peripheral neuropathy was often found, central motor pathways did not appear, at the level they were tested, to be directly or indirectly damaged by the virus. On the contrary, some hyperexcitability seemed to be present.

[Changes in nerve conduction velocity as a result of hyperbaria in man]. / Modification des vitesses de conduction nerveuse par l'hyperbarie chez l'homme.

Nervous conduction was measured in 27 subjects before and after compression in ternary mixture (helium, nitrogen and oxygen) ranging from 5,5 to 12 ATA. Among the eleven parameters studied, three showed an acceleration of the nervous conduction in the distal part of the sensitive and motor fibers. Although no precise mechanism can be established, different factors, in particular the role of ischemia, are discussed.

[Cervical spine and accelerations in aeronautical environment: ergonomic and electromyographic approaches]. / Rachis cervical et accelerations rencontrees en aeronautique: approches ergonomique et electromyographique.

Both, an analysis of the variation of the electromyographic signal with respect to the acceleration endured by flying personnel and an ergonomic evaluation of pilot activity, have been achieved. The authors show then the inadequacy of the muscular response to the high Gz with rapid on set and its functional incompatibility to provide simultaneously a correct bearning contraction and a good mobility of neck. Consequently, the authors propose an instruction of flying personnel about these risks and they determine a specific muscular training.

Effects of high pressure on nervous conduction velocity in man.

The velocities of motor and sensory nervous conduction and of neuro-muscular transmission were measured in four subjects during a simulated dive at 4.6 MPa (46 bars). The results show an increase in motor distal latency in the ulnar nerve, especially during decompression, with reversibility of the effect on return to ambient conditions. The hypothesis of an interaction of dissolved gases with the membranes of ischaemic cells is proposed.