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M A Volonte

Publications and source records attributed to M A Volonte.

4 recordsLinked to original sources
PubMed2002

New perspectives on neurochemical effects of amantadine in the brain of parkinsonian patients: a PET - [(11)C]raclopride study.

Amantadine, is a non competitive NMDA receptors antagonist that has been proved beneficial in Parkinson's disease. However its mechanism of action at therapeutic doses is still under discussion. Aim of this study was to evaluate the effect of repeated administration of amantadine on striatal dopaminergic system by measuring [(11)C]raclopride binding to striatal D(2) dopamine receptors, in patients with moderate idiopathic Parkinson's disease. Eight patients completed the study undergoing a PET scan, before and after 10-14 days treatment with Amantadine (200 mg/day). Patients were on treatment with L-DOPA, which was suspended 1 night before each PET scans, and free from dopaminergic agonists, anticholinergic and antidepressants. Amantadine treatment significantly increased [(11)C-]Raclopride binding (caudate: 10% p = 0.04; putamen 11% p = 0.01). A slight reduction (-7.3%, p = 0.062) of UPDRS total scores was also observed. The increased availability of striatal D(2) receptors, is likely to be caused by drug induced modification of receptors expression. This hypothesis is consistent with previous experiments, indicating an increase in striatal D(2) receptors in rats treated with amantadine or other non competitive NMDA antagonists and suggests that the neo-synthesis of D(2) receptors may represent a reinforcing mechanism of drug efficacy.

Aged↗
PubMed1996

Focal task-specific tremors.

Focal task-specific tremors besides primary writing tremor have rarely been reported in the literature. We describe nine cases of focal tremors induced by different specific tasks, involving a repetitive and frequently performed movement. Only one of these patients had a family history of any similar disorders. There was no overt dystonia in any of the cases, but these tremors may be forms of focal dystonia, rather than a manifestation of essential tremor.

Adult↗
PubMed1996

Pain in multiple system atrophy.

Pain is a recognized feature of idiopathic Parkinson's disease (IPD) but has never been studied in multiple system atrophy (MSA), the commonest cause of atypical parkinsonism. We retrospectively analysed histories of pain in 100 consecutive cases of clinically probable MSA. Details were obtained from the medical records of 100 patients with MSA, comprising 82 with the striatonigral degeneration (SND) type and 18 with the olivopontocerebellar atrophy (OPCA) type of MSA. Pain was reported in 47% of the MSA patients. It was classified as rheumatic in 64% of MSA patients reporting pain, sensory in 28%, dystonic in 21%, and levodopa-related in 16%, mostly related to off-period or diphasic dystonias. There was a mixed pain syndrome in 19% of these patients. Pain was significantly more commonly reported by females (P = 0.02), and by patients with levodopa-induced dyskinesias (P = 0.02). No other clinical feature differentiated MSA patients who reported pain from those who did not. The mean delay between disease onset and onset of pain was 2.9 years, but pain was reported at the time of, or before, disease onset in about 30% of patients. The overall prevalence of pain in MSA was similar to that reported in IPD, but the distribution of pain categories was different.

Adult↗