Publications by authors named "Yong H Ryu"

Although cognitive training has been proposed as a possible therapeutic modality for mild cognitive impairment (MCI), most serious games focus on specific tasks. This study aimed to investigate the feasibility and efficacy of narrative video game-based cognitive intervention for MCI. A four-week (± 1-week) mobile game intervention was given to 17 MCI participants (mean age (SD) = 72.

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Purpose Of The Report: Extrahepatic bile duct (EHD) cancer varies in uptake of FDG. The aim of the present study was to determine the role of glucose transporter (GLUT) 1 and hexokinase (HK) 2 in the glucose metabolism of EHD cancer cells using immunohistochemistry and 18F-FDG PET/CT.

Methods: Twenty-six patients with EHD cancer who underwent baseline PET/CT and surgery were studied.

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Introduction: [(11)C](R)-Rolipram is a selective radioligand for positron emission tomography (PET) imaging of phosphodiesterase 4, an enzyme that metabolizes 3',5'-cyclic adenosine monophosphate. The aim of this study was to estimate the human radiation absorbed dose of the radioligand based on its biodistribution in both monkeys and humans.

Methods: Whole-body PET images were acquired for 2 h after injecting [(11)C](R)-rolipram in eight healthy humans and three monkeys.

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Molecular imaging has been used to estimate both drug-induced and tonic dopamine release in the striatum and most recently extrastriatal areas of healthy humans. However, to date, studies of drug-induced and tonic dopamine release have not been performed in the same subjects. This study performed positron emission tomography (PET) with [18F]fallypride in healthy subjects to assess (1) the reproducibility of [18F]fallypride and (2) both D-amphetamine-induced and alpha-methyl-p-tyrosine (AMPT)-induced changes in dopamin release on [(18)F]fallypride binding in striatal and extrastriatal areas.

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Unlabelled: (11)C-PBR28 ([methyl-(11)C]N-acetyl-N-(2-methoxybenzyl)-2-phenoxy-5-pyridinamine) is a recently developed radioligand to image peripheral benzodiazepine receptors (PBRs) in brain. The aim of this study was to estimate the human radiation doses of (11)C-PBR28 based on biodistribution data in monkeys and humans. In addition, we scanned 1 human subject who fortuitously behaved as if he lacked the PBR binding protein.

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Unlabelled: (18)F-trans-4-Fluoro-N-2-[4-(2-methoxyphenyl)piperazin-1-yl]ethyl]-N-(2-pyridyl)cyclohexanecarboxamide ((18)F-FCWAY) is a PET radioligand for imaging serotonin 5-hydroxytryptamine-1A receptors in brain. (18)F-FCWAY undergoes significant defluorination, with high uptake of radioactivity in the skull and resulting spillover contamination in the underlying neocortex. The cytochrome P450 enzyme CYP2E1 defluorinates many drugs.

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