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

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

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See detailCombined study of cerebral glucose metabolism and [11C] methionine accumulation in probable Alzheimer's disease using positron emission tomography
Salmon, Eric ULg; Grégoire, M. C.; Delfiore, Guy et al

in Journal of Cerebral Blood Flow & Metabolism (1996), 16(3), 399-408

There is a characteristic decrease in glucose metabolism in associative frontal and temporo-parietal cortices of patients suffering from Alzheimer's disease (AD). The decrease in metabolism might result ... [more ▼]

There is a characteristic decrease in glucose metabolism in associative frontal and temporo-parietal cortices of patients suffering from Alzheimer's disease (AD). The decrease in metabolism might result from local neuronal loss or from a decrease of synaptic activity. We measured in vivo [11C]methionine accumulation into proteins with positron emission tomography (PET) to assess cortical tissue loss in AD. Both global regional activity and compartmental analysis were used to express [11C]methionine accumulation into brain tissue. Glucose metabolism was measures with [18F]fluorodeoxyglucose and autoradiographic method. Combined studies were performed in 10 patients with probable AD, compared to age-matched healthy volunteers. There was a significant 45% decrease of temporo-parietal glucose metabolism in patients with AD, and frontal metabolism was lowered in most patients. Temporo-parietal metabolism correlated to dementia severity. [11C]methionine incorporation into temporo-parietal and frontal cortices was not significantly decreased in AD. There was no correlation with clinical symptoms. Data suggest that regional tissue loss, assessed by the decrease of [11C]methionine accumulation, is not sufficient to explain cortical glucose hypometabolism, which reflects, rather, reduced synaptic connectivity. [less ▲]

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See detailBrain activation induced by estimation of duration : A PET study
Maquet, Pierre ULg; Lejeune, Helga ULg; Pouthas, V. et al

in Neuroimage (1996), 3(2), 119-126

Duration information about a visual stimulus requires processing as do other visual features such as size or intensity. Using positron emission tomography, iterative (H2O)-O-15 infusions, and statistical ... [more ▼]

Duration information about a visual stimulus requires processing as do other visual features such as size or intensity. Using positron emission tomography, iterative (H2O)-O-15 infusions, and statistical parametric mapping, we investigated the neural correlates of time processing. Nine normal subjects underwent six serial rCBF. Three tasks were studied: (a) Atemporal generalization task (D task) in which the subjects had to judge (by pressing one of two keys) whether the duration of the illumination of a green LED was equal to or different from that of a previously presented standard; (b) An intensity generalization task. (I task) in which the judgment concerned the intensity of the LED; and (c) A control task (C task) in which the subjects had to press one of the two keys at random in response to LED illumination. A significant increase in rCBF during the D task, compared to that during the C task, was observed in right prefontal cortex, right inferior parietal lobule, anterior cingulate cortex, vermis, and a region corresponding to the left fusiform gyrus. A significant increase in rCBF during the I task, compared to that during the C task, was observed in right prefontal cortex, right inferior parietal lobule, right extrastriate cortex, anterior cingulate cortex, left inferior parietal lobule, vermis, and two symmetrical regions corresponding to the fusiform gyri. No significant activation was observed in the D task when compared to that in the I task. We propose that these cortical maps are best explained by the recruitment of visual attention and memory structures, which play a major role in prospective time judgements as indicated by behavioral studies. The data also suggest that the temporal dimension of a visual stimulus is processed in attributes. the same areas as other visual attributes. [less ▲]

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See detailFrontal activation observed with PET in visual discrimination involving duration or intensity parameters
Maquet, Pierre ULg; Lejeune, Helga ULg; Pouthas, V. et al

in Proceedings of the sixth meeting of the European Neurological Society, Tutzing (Munich), RFA, June 17-21 (1995)

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See detailSep Pak as alternative to rotary evaporators for radiopharmaceutical formulations.
Lemaire, Christian ULg; Plenevaux, Alain ULg; Del Fiore, G. et al

in Journal of Labelled Compounds & Radiopharmaceuticals (1995), 37

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See detailDifferential diagnosis of Alzheimer's disease with PET.
Salmon, Eric ULg; Sadzot, Bernard ULg; Maquet, Pierre ULg et al

in Journal of Nuclear Medicine : Official Publication, Society of Nuclear Medicine (1994), 35(3), 391-8

PET studies have demonstrated bilateral temporo-parietal hypoperfusion and hypometabolism in probable and definite Alzheimer's disease (AD), a pattern that may help differentiate AD from other dementias ... [more ▼]

PET studies have demonstrated bilateral temporo-parietal hypoperfusion and hypometabolism in probable and definite Alzheimer's disease (AD), a pattern that may help differentiate AD from other dementias. METHODS: To evaluate the diagnostic power of cerebral metabolic distribution patterns for "cortical" degenerative dementias, PET scans obtained from 129 patients referred for differential diagnosis of dementia were analyzed visually. RESULTS: Sixty-five patients had a final clinical diagnosis of probable AD. Ninety-seven percent (97%) of those had abnormal metabolic scans and 94% showed a suggestive pattern of bilateral or unilateral temporo-parietal hypometabolism (with or without frontal involvement). Hypometabolism was unilateral in 23% of patients. Five subjects with a neuropathologically proven diagnosis of Alzheimer's disease had a suggestive metabolic pattern. One of those was an early case with frontal hypometabolism exceeding temporo-parietal involvement. Two patients with Alzheimer's-type dementia had isolated bilateral frontal hypometabolism. CONCLUSIONS: This alternative metabolic pattern may correspond to a non-Alzheimer pathology occurring in 10%-20% of patients suffering from clinically probable Alzheimer's disease. Most of the patients with possible but atypical Alzheimer's-type dementia showed isolated bilateral frontal involvement. This metabolic pattern probably corresponds to different diseases, such as Pick's disease, frontal lobe dementia or progressive subcortical gliosis. [less ▲]

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See detailEnantioselective syntheses of n.c.a. L-(a-methyl)-[b-11C]-4-chlorophenylalanine and L-(a-[11C]methyl-tryptophan.
Plenevaux, Alain ULg; Al-Darwich, M. J.; Lemaire, Christian ULg et al

in Journal of Labelled Compounds & Radiopharmaceuticals (1994), 35

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See detailN.C.A. asymmetric syntheses of a-methyl and b-hydroxy a-amino acid labelled with fluorine-18 for probing enzymatic function.
Damhaut, Ph.; Lemaire, Christian ULg; Plenevaux, Alain ULg et al

in Journal of Labelled Compounds & Radiopharmaceuticals (1994), 35

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See detail11C-alkylation on Al2O3/MF: a useful method for rapid labelling.
Schmitz, F.; Plenevaux, Alain ULg; Del Fiore, G. et al

in Journal of Labelled Compounds & Radiopharmaceuticals (1994), 35

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See detailRobot-assisted synthesis of [18F]altanserin, 4-[18F]fluorotropapride, 6-[18F]fluoro-L-dopa and 2-[18F]fluoro-L-tyrosine.
Brihaye, C.; Lemaire, Christian ULg; Damhaut, Ph. et al

in Journal of Labelled Compounds & Radiopharmaceuticals (1994), 35

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See detailEnantioselective synhteses of n.c.a. L-2-[18F]fluoro-4-chlorophenylalanine and of L-(a-methyl)-2-[18F]fluoro-4-chlorophenylalanine.
Al-Darwich, M. J.; Plenevaux, Alain ULg; Lemaire, Christian ULg et al

in Journal of Nuclear Medicine : Official Publication, Society of Nuclear Medicine (1994), 35

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See detailAl2O3/KF in radiochemistry: fast preparation of L-[11C-methyl]methionine without HPLC.
Schmitz, F.; Plenevaux, Alain ULg; Del Fiore, G. et al

in Journal of Nuclear Medicine : Official Publication, Society of Nuclear Medicine (1994), 35

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