References of "Aerts, Joël"
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See detailAuditory processing in the vegetative state.
Laureys, Steven ULg; Faymonville, Marie ULg; Degueldre, Christian ULg et al

in Brain : A Journal of Neurology (2000), 123 ( Pt 8)

H(2)(15)O-PET was used to investigate changes in regional cerebral blood flow in response to auditory stimulation in patients in the vegetative state. Five patients in a vegetative state of hypoxic origin ... [more ▼]

H(2)(15)O-PET was used to investigate changes in regional cerebral blood flow in response to auditory stimulation in patients in the vegetative state. Five patients in a vegetative state of hypoxic origin were compared with 18 age-matched controls. In addition, the cerebral metabolism of these patients and 53 age-matched controls was studied using [(18)F]fluorodeoxyglucose. In control subjects, auditory click stimuli activated bilateral auditory cortices [Brodmann areas (BA) 41 and 42] and the contralateral auditory association cortices (BA 22). In the patients, although resting metabolism was decreased to 61% of normal values, bilateral auditory areas 41 and 42 showed activation as seen in the controls, but the temporoparietal junction cortex (BA 22) failed to be activated. Moreover, the auditory association cortex was functionally disconnected from the posterior parietal association area (BA 40), the anterior cingulate cortex (BA 24) and the hippocampus, as revealed by psychophysiological interaction analysis. Thus, despite altered resting metabolism, the auditory primary cortices were still activated during external stimulation, whereas hierarchically higher-order multi- modal association areas were not. Such a cascade of functional disconnections along the auditory cortical pathways, from the primary auditory areas to multimodal and limbic areas, suggests that the residual cortical processing observed in the vegetative state cannot lead to the integrative processes that are thought to be necessary for the attainment of the normal level of awareness. [less ▲]

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See detailTissue distribution, autoradiography, and metabolism of 4-(2'-methoxyphenyl)-1-[2' -[N-2"-pyridinyl)-p-[(18)F]fluorobenzamido]ethyl]piperazine (p-[(18)F]MPPF), a new serotonin 5-HT(1A) antagonist for positron emission tomography: An In vivo study in rats.
Plenevaux, Alain ULg; Weissmann, D.; Aerts, Joël ULg et al

in Journal of Neurochemistry (2000), 75(2), 803-11

The in vivo behavior of 4-(2'-methoxyphenyl)-1-[2'-[N-(2"-pyridinyl)-p-[(18)F]fluorobenzamido ]ethyl]-piperazine (p-[(18)F]MPPF), a new serotonin 5-HT(1A) antagonist, was studied in awake, freely moving ... [more ▼]

The in vivo behavior of 4-(2'-methoxyphenyl)-1-[2'-[N-(2"-pyridinyl)-p-[(18)F]fluorobenzamido ]ethyl]-piperazine (p-[(18)F]MPPF), a new serotonin 5-HT(1A) antagonist, was studied in awake, freely moving rats. Biodistribution studies showed that the carbon-fluorine bond was stable in vivo, that this compound was able to cross the blood-brain barrier, and that a general diffusion equilibrium could account for the availability of the tracer. The great quantity of highly polar metabolites found in plasma did not contribute to the small amounts of metabolites found in hippocampus, frontal cortex, and cerebellum. Exvivo p-[(18)F]MPPF and in vitro 8-hydroxy-2-(di-n-[(3)H]propylamino)tetralin autoradiography were compared both qualitatively and quantitatively. Qualitative evaluation proved that the same brain regions were labeled and that the p-[(18)F]MPPF labeling is (a) in total agreement with the known distribution of 5-HT(1A) receptors in rats and (b) characterized by very low nonspecific binding. Quantitative comparison demonstrated that the in vivo labeling pattern obtained with p-[(18)F]MPPF cannot be explained by differences in regional blood flow, capillary density, or permeability. The 5-HT(1A) specificity of p-[(18)F]MPPF and binding reversibility were confirmed in vivo with displacement experiments. Thus, this compound can be used to evaluate parameters characterizing 5-HT(1A) binding sites in the brain. [less ▲]

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See detailImpaired effective cortical connectivity in vegetative state : Preliminary investigation using PET
Laureys, Steven ULg; Goldman, Serge; Phillips, Christophe ULg et al

in Neuroimage (1999), 9(4), 377-382

Vegetative state (VS) is a condition of abolished awareness with persistence of arousal. Awareness is part of consciousness, which itself is thought to represent an emergent property of cerebral neural ... [more ▼]

Vegetative state (VS) is a condition of abolished awareness with persistence of arousal. Awareness is part of consciousness, which itself is thought to represent an emergent property of cerebral neural networks. Our hypothesis was that part of the neural correlate underlying VS is an altered connectivity, especially between the associative cortices. We assessed regional cerebral glucose metabolism (rCMRGlu) and effective cortical connectivity in four patients in VS by means of statistical parametric mapping and [F-18]fluorodeoxyglucose-positron emission tomography. Our data showed a common pattern of impaired rCMRGlu in the prefrontal, premotor, and parietotemporal association areas and posterior cingulate cortex/precuneus in VS. In a next step, we demonstrated that in VS patients various prefrontal and premotor areas have in common that they are less tightly connected with the posterior cingulate cortex than in normal controls. These results provide a strong argument for an alteration of cortical connectivity in VS patients. (C) 1999 Academic Press. [less ▲]

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See detail5-HT1A Receptors visualization with p-[18F]MPPF in healthy volunteers.
Plenevaux, Alain ULg; Lemaire, Christian ULg; Salmon, Eric ULg et al

in Journal of Labelled Compounds & Radiopharmaceuticals (1999), 42

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See detailp-[18F]MPPF, a fluoro analog of WAY-100635 for visualisation of 5-HT1A receptors in cat.
Le Bars, D.; Ginovart, N.; Hassoun, W. et al

in Journal of Labelled Compounds & Radiopharmaceuticals (1999), 42

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See detailThe synthesis of 6-[18F]fluoro-L-dopa by chiral catalytic phase-transfer alkylation.
Lemaire, Christian ULg; Guillouet, S.; Plenevaux, Alain ULg et al

in Journal of Labelled Compounds & Radiopharmaceuticals (1999), 42

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See detailIn vivo studies of p-[18F]MPPF metabolites in human.
Damhaut, Ph.; Plenevaux, Alain ULg; Lemaire, Christian ULg et al

in Journal of Labelled Compounds & Radiopharmaceuticals (1999), 42

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See detail5-HT1A receptor distribution in the human brain: preliminary PET data with p-[18F]MPPF.
Fuchs, Sonia ULg; Plenevaux, Alain ULg; Degueldre, Christian ULg et al

in Society for Neuroscience / Abstracts (1999), 25

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See detailp-[18F]MPPF, 5-HT1A antagonist: comparison to [3H]8-OH-DPAT with autoradiography
Plenevaux, Alain ULg; Weissmann, D.; Lemaire, Christian ULg et al

in Society for Neuroscience / Abstracts (1999)

p-MPPF 4-(2’-methoxyphenyl)-1-[2’-[N-(2’’-pyridinyl)-p-fluorobenzamido] ethyl]piperazine is the para-fluorobenzoyl analog of the highly selective 5-HT1A antagonist WAY-100635. The one step procedure used ... [more ▼]

p-MPPF 4-(2’-methoxyphenyl)-1-[2’-[N-(2’’-pyridinyl)-p-fluorobenzamido] ethyl]piperazine is the para-fluorobenzoyl analog of the highly selective 5-HT1A antagonist WAY-100635. The one step procedure used to label p-MPPF with fluorine-18 (cyclotron produced positron emitter of 110 min half-life) leads to a radiopharmaceutical compound easily prepared on a large scale. The preliminary evaluations conducted in rats and cats are good reason to consider p-[18F]MPPF as an interesting reversible radioligand to study the 5-HT1A receptor family in humans with positron emission tomography (PET). In this paper we report a careful comparison between p-[18F]MPPF and [3H]8-OH-DPAT with autoradiography and quantitative densitometry in the same animal. All experiments were conducted in Sprague Dawley male rats. For p-[18F]MMPF, the results were obtained ex-vivo after an intravenous injection of high specific activity radioligand (0.8-1.5 Ci/µmol) in vigil (no anesthesia), free moving and unstressed animals. For the purpose, permanent cannulation of the posterior vena cava were realized at least four days in advance. The [3H]8-OH-DPAT results were obtained in vitro on adjacent coronal sections to the one used for the p-[18F]MPPF autoradiography. Quantitative densitometry was employed to compare the values obtained in relevant brain structures (frontal cortex, lateral septum, hippocampus, dorsal raphe, entorhinal cortex and cerebellum). The plot of the p-[18F]MPPF values obtained for each structure against the [3H]8-OH-DPAT results displayed a significant linear correlation. These results demonstrate that from a qualitative as well as quantitative point of view, the binding of p-[18F]MPPF is totally comparable to the one of [3H]8-OH-DPAT. Supported by grants from INSERM/CGRI and FNRS Belgium. [less ▲]

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See detailSolid phase extraction : An alternative to the use of rotary evaporators for solvent removal in the rapid formulation of PET radiopharmaceuticals
Lemaire, Christian ULg; Plenevaux, Alain ULg; Aerts, Joël ULg et al

in Journal of Labelled Compounds & Radiopharmaceuticals (1999), 42(1), 63-75

Solid phase extraction (SPE) was used for the formulation of several radiopharmaceuticals. The method involves dilution of the previously purified HPLC compound with water, trapping of the activity on an ... [more ▼]

Solid phase extraction (SPE) was used for the formulation of several radiopharmaceuticals. The method involves dilution of the previously purified HPLC compound with water, trapping of the activity on an SPE bed, washing off the support, elution of the radiopharmaceutical with a small volume of ethanol (<1 mL) and dilution with sterile isotonic saline solution. Recovery of the radiopharmaceuticals was always higher than 97%. Two different methods of automation were developed for the formulation of [11C] and [18F]radiopharmaceuticals. In all cases, organic solvent levels in the injectable solution were below the recommended limits. This fast (3-6 min.) and easy to automate process can be considered as an alternative to the conventional methods (rotary evaporators). Copyright © 1999 John Wiley [less ▲]

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See detailMetabolism of no-carrier-added 2-[18F]fluoro-L-tyrosine in free mooving rats.
Aerts, Joël ULg; Plenevaux, Alain ULg; Lemaire, Christian ULg et al

in Society for Neuroscience / Abstracts (1998), 24

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See detailHigh-yield radiosynthesis and preliminary in vivo evaluation of p-[18F]MPPF, a fluoro analog of WAY-100635.
Le Bars, Didier; Lemaire, Christian ULg; Ginovart, N. et al

in Nuclear Medicine & Biology (1998), 25(4), 343-50

No-carrier-added 4-[18F]fluoro-N-[2-[1-(2-methoxyphenyl)-1 piperazinyl]ethyl-N-2-pyridinyl-benzamide (p-[18F]MPPF) was synthesized by nucleophilic substitution of the corresponding nitro compound in the ... [more ▼]

No-carrier-added 4-[18F]fluoro-N-[2-[1-(2-methoxyphenyl)-1 piperazinyl]ethyl-N-2-pyridinyl-benzamide (p-[18F]MPPF) was synthesized by nucleophilic substitution of the corresponding nitro compound in the presence of Kryptofix 222 and K2CO3 by microwave heating (3 min, 500 W) using a remotely controlled radiosynthesis. Baseline separation of p-[18F]MPPF from the nitro derivative was performed on a semipreparative HPLC C18 column. After Sep-Pak formulation, the radiopharmaceutical was obtained with a radiochemical yield of 25% (EOS) in about 70 min. Specific radioactivity averaged between 1-5 Ci/micromol EOS. Labelling of the ortho and meta derivatives was also attempted. Brain uptake of p-[18F]MPPF was studied with PET on fluothane-anesthetized cats. Following intravenous injection of p-[18F]MPPF, high accumulation of radioactivity was observed in the hippocampus and cerebral cortex. Low levels of radioactivity were observed in cerebellum. At 30 min, the mean hippocampus/cerebellum and cortex/cerebellum ratios were 5 and 3.8, respectively. The accumulation of the tracer was blocked by prior administration of reference WAY-100635, demonstrating the specificity of the ligand. [less ▲]

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See detailMétabolisme du p-[18]MPPF (antagoniste 5-HT1A) chez le rat
Plenevaux, Alain ULg; Aerts, Joël ULg; Lemaire, Christian ULg et al

Poster (1997, May 29)

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See detailMétabolisme de la 6-fluoro-L-tyrosine chez le rat
Aerts, Joël ULg; Plenevaux, Alain ULg; Lemaire, Christian ULg et al

Poster (1997, May 29)

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See detailLe p-[18F]MPPF: un nouveau ligand pour l'étude par TEP des récepteurs 5-HT1A
Ginovart, Nathalie; Le Bars, Didier; Lemaire, Christian ULg et al

Poster (1997, May 25)

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See detailMicrowave improved synthesis of p-[18F]MPPF, 5-HT1A antagonist and PET sudies on cat brain.
Le Bars, D.; Ginovart, N.; Lemaire, Christian ULg et al

in Journal of Labelled Compounds & Radiopharmaceuticals (1997), 40

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See detailSynthesis of [18F]FDG with alkaline hydrolysis on a low polarity solid phase support.
Lemaire, Christian ULg; Damhaut, Ph.; Lauricella, Benjamino ULg et al

in Journal of Labelled Compounds & Radiopharmaceuticals (1997), 40

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See detailMetabolism of no carrier added 2-[18F]fluoro-L-tyrosine in free moving rats.
Aerts, Joël ULg; Plenevaux, Alain ULg; Lemaire, Christian ULg et al

in Journal of Labelled Compounds & Radiopharmaceuticals (1997), 40

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See detailTissue distribution, autoradiography and metabolism in rats of p-[18F]MPPF: 5-HT1A antagonist.
Plenevaux, Alain ULg; Aerts, Joël ULg; Lemaire, Christian ULg et al

in Journal of Labelled Compounds & Radiopharmaceuticals (1997), 40

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See detailHigh yield radiosynthesis of p-[F-18]MPPF, 5-HT1A antagonist, and PET studies in cat brain.
Le Bars, D.; Lemaire, Christian ULg; Plenevaux, Alain ULg et al

in Journal of Nuclear Medicine : Official Publication, Society of Nuclear Medicine (1997), 38

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