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Bertrand Degos

Publications and source records attributed to Bertrand Degos.

4 recordsLinked to original sources

NDRG1-linked Charcot-Marie-Tooth disease (CMT4D) with central nervous system involvement.

Charcot-Marie-Tooth disease type 4D (CMT4D) is an autosomal recessive demyelinating polyneuropathy, associated with deafness exclusively found in Gypsies and resulting from a homozygous R148X mutation in the N-myc downstream-regulated gene 1 (NDRG1). We report the detailed phenotypic study of a family without Gypsy ancestry, who presented with severe demyelinating polyneuropathy, deafness, subcortical white matter abnormalities on brain magnetic resonance imaging studies, and the R148X mutation in NDRG1. For the first time, central nervous system white matter lesions are demonstrated in CMT4D. This report extends the clinical knowledge of CMT4D and indicates that the role of the R148X mutation in NDRG1 in the central nervous system should be further studied.

Adolescent↗

A study of three patients with amyotrophic lateral sclerosis and a polyneuropathy resembling CIDP.

We report three patients with a syndrome that fulfilled clinical and laboratory criteria for definite chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) who failed immunosuppressive treatment and eventually developed progressive amyotrophic lateral sclerosis (ALS). Mean disease duration was 23 months (13-38) before death. Two patients had a family history of ALS without mutations of the SOD1 gene. Postmortem examination in one patient showed an endoneurial infiltration of mononuclear cells in lumbar roots and distal and proximal peripheral nerves, mainly around myelinated fibers, with demyelination and axonal loss, consistent with CIDP. The spinal cord revealed severe neuronal loss in the anterior horn, axonal loss in the corticospinal tract, and large numbers of phagocytes in the anterior and lateral tracts, indicative of ALS. Whether demyelinating polyneuropathy was coincident with ALS or was a cause or consequence of motor neuron degeneration in these patients remains to be elucidated. This unusual combination may provide an important clue in elucidating the pathogenesis of ALS in some patients.

Adult↗

Neuroleptic-induced catalepsy: electrophysiological mechanisms of functional recovery induced by high-frequency stimulation of the subthalamic nucleus.

High-frequency stimulation (HFS) of the subthalamic nucleus (STN) remarkably alleviates motor disorders in parkinsonian patients. The mechanisms by which STN HFS exerts its beneficial effects were investigated in anesthetized rats, using a model of acute interruption of dopaminergic transmission. Combined systemic injections of SCH-23390 [R(+)-7-chloro-8-hydroxy-3-methyl-1-phenyl-2,3,4,5,-tetrahydro-1H-3-benzazepine] and raclopride, antagonists of the D1 and D2 classes of dopaminergic receptors, respectively, were performed, and the parameters of STN HFS that reversed the neuroleptic-induced catalepsy were determined in freely moving animals. The effects of neuroleptics and the impact of STN HFS applied at parameters alleviating neuroleptic-induced catalepsy were analyzed in the substantia nigra pars reticulata (SNR), a major basal ganglia output structure, by recording the neuronal firing pattern and the responses evoked by cortical stimulation. Neuroleptic injection altered the tonic and regular mode of discharge of SNR neurons, most of them becoming irregular with bursts of spikes and pauses. The inhibitory component of the cortically evoked response, which is attributable to the activation of the direct striatonigral circuit, was decreased, whereas the late excitatory response resulting from the indirect striato-pallido-subthalamo-nigral circuit was reinforced. During STN HFS, the spontaneous firing of SNR cells was either increased or decreased with a global enhancement of the firing rate in the overall population of SNR cells recorded. However, in all of the cases, SNR firing pattern was regularized, and the bias between the trans-striatal and trans-subthalamic circuits was reversed. By these effects, STN HFS restores the functional properties of the circuits by which basal ganglia contribute to motor activity.

Action Potentials↗