Brief Communication External globus pallidus stimulation modulates brain connectivity in Huntington's disease

Positron emission tomography with O-15-labeled water was used to study at rest the neurophysiological effects of bilateral external globus pallidus (GPe) deep brain stimulation in patients with Huntington's disease (HD). Five patients were compared with a control group in the on and off states of the stimulator. External globus pallidus stimulation decreased neuronal activity and modulated cerebral connectivity within the basal ganglia-thalamocortical circuitry, the sensorimotor, and the default-mode networks. These data indicate that GPe stimulation modulates functional integration in HD patients in accordance with the basal ganglia-thalamocortical circuit model

Analysis of single-joint rapid movements in patients with sporadic olivopontocerebellar atrophy

Patients with pure cerebellar cortical atrophy (CCA) present isolated cerebellar signs, whereas patients with sporadic olivopontocerebellar atrophy (sOPCA) present various combinations of cerebellar and extracerebellar signs. However, the differential diagnosis between these two forms of cerebellar degeneration is often a challenge for the clinician. Therefore, any test helping in this differential diagnosis might have a potential clinical interest. In this study, our goal was to investigate the adaptation to increased inertia in patients with sOPCA exhibiting combined cerebellar and pyramidal signs, during the performance of fast wrist flexions. We found that these patients exhibited a hypermetria which remained unchanged after addition of inertia, because they were unable to increase neither their agonist activity (launching force), nor their antagonist activity (braking force). This contrasts with our previous findings in patients with CCA. In these latter, the hypermetria worsened when the inertial load of the hand increased because those patients were able to increase their agonist activity, but not their antagonist activity. The adaptation to inertia might thus help to differentiate CCA and sOPCA.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Automatic synthesis of [18F]altanserin, a radiopharmaceutical for positron emission tomographic studies of the serotonergic type-2 receptors

[18F]Altanserin is routinely used in several centers to study the serotonergic type-2 receptors (5HT2) with positron emission tomography (PET). An automatic production system allowing the preparation of multimillicurie amounts [>1.5 GBq (40 mCi) EOS, mean radiochemical yield 20 = 6% EOB, specific activity >1 Ci/·mol (mean = 2.8 Ci/μmol) n = 50] of this radiopharmaceutical within a synthesis time of 90 minutes (quality controls included) is described in this paper. The apparatus includes the recovery of the activity from the target, the preparation of the dried [18F]KF/kryptofix 2.2.2 complex, the labeling reaction using a microwave cavity, the Sep Pak and HPLC purification. A sterile, pyrogen-free and single use unit was also developed for the formulation of the injectable solution. This last part could be used for the formulation of many other radiopharmaceuticals. Copyright © 1998 Elsevier Science Inc. All rights reserved.SCOPUS: re.jinfo:eu-repo/semantics/publishe

A PET study of auditory selective and divided attention modulated by difficulty

info:eu-repo/semantics/publishe

Nucleophilic [18F]radiofluorination using microwave cavity: Application to [18F]FDG and aromatic [18F]fluoro amino acids synthesis

SCOPUS: cp.jFLWNAinfo:eu-repo/semantics/publishedSupplement: Tenth International Symposium on Radiopharmaceutical Chemistry Abstract

Quality assurance and quality controls in the routine production of [13N]NH4+ using the 16O(p,α)13N nuclear reaction

SCOPUS: cp.jFLWNOinfo:eu-repo/semantics/publishe

Production, automatic delivery and bolus injection of [15O]water for positron emission tomography studies

An automatic system allowing repetitive bolus injection of oxygen-15-labeled water for PET studies is described in this report. The production of this radiopharmaceutical by the 16O(p,pn)15O nuclear reaction on H216O, its purification and delivery nearby the PET camera, the injection system, and the quality controls are presented.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

External globus pallidus stimulation modulates brain connectivity in Huntington's disease.

Positron emission tomography with O-15-labeled water was used to study at rest the neurophysiological effects of bilateral external globus pallidus (GPe) deep brain stimulation in patients with Huntington's disease (HD). Five patients were compared with a control group in the on and off states of the stimulator. External globus pallidus stimulation decreased neuronal activity and modulated cerebral connectivity within the basal ganglia-thalamocortical circuitry, the sensorimotor, and the default-mode networks. These data indicate that GPe stimulation modulates functional integration in HD patients in accordance with the basal ganglia-thalamocortical circuit model.Journal ArticleResearch Support, Non-U.S. Gov'tSCOPUS: ar.jinfo:eu-repo/semantics/publishe