L'ataxie de Friedreich: Donnees recentes et perspectives therapeutiques: Friedreich ataxia :Recent developments and prospects for treatment

Friedreich's ataxia (FRDA) is the most frequent cause of recessive ataxias. Neurological examination shows oculo-motor ataxia, dysarthria, limbs ataxia, tendon areflexia, pyramidal signs and sensory deficits. Extraneurological involvement consists in osteoarticular deformities, cardiomyopathy and diabetes mellitus. Neurological deficits and osteoarticular deformities both contribute to the gait disorder, which is the main disabling deficit. In 98 % of the cases, a trinucleotide repeat is found in chromosome 9. Gene implicated in FRDA codes for a protein called frataxin. Experimental studies have revealed iron accumulation in mitochondria of neurons and cardiomyocytes, suggesting that frataxin plays a determinant role in intramitochondrial iron homeostasis. These discoveries are now considered as a clue for new strategies of treatment in this hereditary disease.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

3 Hz leg tremor in a cerebellar syndrome following lithium intoxication

SCOPUS: le.jFLWINinfo:eu-repo/semantics/publishe

Etude de la reproductibilite inter-observateur de l'evaluation d'une nouvelle manoeuvre de pointage horizontal: Comparaison avec les tests cliniques conventionnels

Finger-to-nose test, fine finger movements, to maintain arms against gravity, alternate movements of hands, Barany's test, muscle tone evaluation, Stewart-Holmes test and handwriting are the conventional clinical tests most frequently used in daily practice to evaluate voluntary movements of the upper limb. We describe a new clinical manoeuvre consisting of a horizontal pointing movement of one upper limb (the moving limb) towards the contralateral motionless limb. We have analyzed the reliability of our new test and of the conventional tests between 2 observers using kappa statistics in a group of 34 right-handed neurological patients. Agreement is very good for our test, since k has a value of 0.63 for left upper limb and a value of 0.64 for right upper limb. The only conventional test characterized by a higher interobserver reliability is handwriting. Furthermore, our manoeuvre is original, as attested by partial association coefficients analysis between our test and conventional tests. This might be due to the fact that our manoeuvre is the sole test investigating rapid proximal movements towards a fixed area in space. In conclusion, our horizontal pointing manoeuvre has a very good reliability between 2 observers and appears original.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Visually-guided isometric force control is not impaired in manic-depressive illness chronically treated with lithium salts.

LetterResearch Support, Non-U.S. Gov'tinfo:eu-repo/semantics/publishe

Kinematics of fast wrist movements in manic-depressive illness chronically treated with lithium carbonate.

Lithium salts have been shown to impair kinematics of fast voluntary movements during acute intoxication. The aim of the present study was to determine whether lithium carbonate affected the kinematics of fast movements in patients chronically treated and who did not exhibit signs of neurotoxicity. We analysed fast wrist flexion movements in 6 healthy subjects, in 5 patients presenting a manic-depressive illness without treatment, and in 8 patients receiving lithium carbonate for a manic-depressive disease. The mean duration of treatment was 3.9 +/- 4.1 years, the mean daily dose 837 +/- 341 mg and the mean serum level 0.95 +/- 0.15 mEq/l. Although mean movement amplitudes were similar in the 3 groups, the variability of fast movements was increased in patients receiving lithium salts. The ratio of maximum to average velocities (Vm/Vave) was significantly higher in patients treated, and their movements were temporally asymmetrical, with a ratio of acceleration duration divided by deceleration duration being lower than in the 2 other groups. These kinematic abnormalities show that a chronic treatment with lithium salts is associated with an impairment of the cerebellar control of fast single-joint movements.Journal ArticleResearch Support, Non-U.S. Gov'tinfo:eu-repo/semantics/publishe