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11 papers found.
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Reliable radiosynthesis of 4-[10B]borono-2-[18F]fluoro-l-phenylalanine with quality assurance for boron neutron capture therapy-oriented diagnosis

ObjectiveThe aim of this study was to establish a reliable and routine method for the preparation of 4-[10B]borono-2-[18F]fluoro-l-phenylalanine (l-[18F]FBPA) for boron neutron capture therapy-oriented diagnosis using positron emission tomography.MethodsTo produce l-[18F]FBPA by electrophilic fluorination of 4-[10B]borono-l-phenylalanine (l-BPA) with [18F]acetylhypofluorite ([18F...

Assessment of safety, efficacy, and dosimetry of a novel 18-kDa translocator protein ligand, [11C]CB184, in healthy human volunteers

Background N,N-di-n-propyl-2-[2-(4-[11C]methoxyphenyl)-6,8-dichloroimidazol[1,2-a]pyridine-3-yl]acetamide ([11C]CB184) is a novel selective radioligand for the 18-kD translocator protein (TSPO), which is upregulated in activated microglia in the brain, and may be useful in positron emission tomography (PET). We examined the safety, radiation dosimetry, and initial brain imaging...

Determination of radionuclides and radiochemical impurities produced by in-house cyclotron irradiation and subsequent radiosynthesis of PET tracers

Objective To elucidate the radionuclides and radiochemical impurities included in radiosynthesis processes of positron emission tomography (PET) tracers. Methods Target materials and PET tracers were produced using a cyclotron/synthesis system from Sumitomo Heavy Industry. Positron and γ-ray emitting radionuclides were quantified by measuring radioactivity decay and using the...

Comparison of 4′-[methyl-11C]thiothymidine (11C-4DST) and 3′-deoxy-3′-[18F]fluorothymidine (18F-FLT) PET/CT in human brain glioma imaging

Background 3′-deoxy-3′-[18F]fluorothymidine (18F-FLT) has been used to evaluate tumor malignancy and cell proliferation in human brain gliomas. However, 18F-FLT has several limitations in clinical use. Recently, 11C-labeled thymidine analogue, 4′-[methyl-11C]thiothymidine (11C-4DST), became available as an in vivo cell proliferation positron emission tomography (PET) tracer. The...

Evaluation of [11C]CB184 for imaging and quantification of TSPO overexpression in a rat model of herpes encephalitis

Purpose Evaluation of translocator protein (TSPO) overexpression is considered an attractive research tool for monitoring neuroinflammation in several neurological and psychiatric disorders. [11C]PK11195 PET imaging has been widely used for this purpose. However, it has a low sensitivity and a poor signal-to-noise ratio. For these reasons, [11C]CB184 was evaluated as a...

A pilot study of 4′-[methyl-11C]-thiothymidine PET/CT for detection of regional lymph node metastasis in non-small cell lung cancer

, Jun Toyohara, and Kiichi Ishiwata), a Grant-in Aid for Scientific Research (B) No. 22390241 from the Japan Society for the Promotion of Science (to Jun Toyohara), and a Grant-in Aid for Young Scientists

Comparison of 11C-4′-thiothymidine, 11C-methionine, and 18F-FDG PET/CT for the detection of active lesions of multiple myeloma

Purpose The aims of this study were to evaluate the possibility of using 11C-methionine (11C-MET) and 11C-4′-thiothymidine (11C-4DST) whole-body PET/CT for the imaging of amino acid metabolism and DNA synthesis, respectively, when searching for bone marrow involvement in patients with multiple myeloma (MM) and to compare these findings with those for 18F-FDG PET/CT and aspiration...

Radiosynthesis and in vivo evaluation of two imidazopyridineacetamides, [11C]CB184 and [11C]CB190, as a PET tracer for 18 kDa translocator protein: direct comparison with [11C](R)-PK11195

Objective We report synthesis of two carbon-11 labeled imidazopyridines TSPO ligands, [11C]CB184 and [11C]CB190, for PET imaging of inflammatory process along with neurodegeneration, ischemia or brain tumor. Biodistribution of these compounds was compared with that of [11C]CB148 and [11C](R)-PK11195. Methods Both [11C]CB184 and [11C]CB190 having 11C-methoxyl group on an aromatic...

Pharmacological Characterization of [3H]CHIBA-3007 Binding to Glycine Transporter 1 in the Rat Brain

Glycine transporter-1 (GlyT-1) in glial cells regulates extracellular levels of glycine, which acts as an obligatory co-agonist at the N-methyl-D-aspartate (NMDA) receptors in the brain. In the present study, we developed a novel radioligand, [3H]3-chloro-N-((S)-((R)-1-methylpiperidin-2-yl)(thiophen- 3-yl)methyl)-4- (trifluoromethyl)picolinamide ([3H]CHIBA-3007), for studying...

In Vivo Evaluation of α7 Nicotinic Acetylcholine Receptor Agonists [11C]A-582941 and [11C]A-844606 in Mice and Conscious Monkeys

In Vivo Evaluation of a7 Nicotinic Acetylcholine Receptor 11 11 Agonists [ C]A-582941 and [ C]A-844606 in Mice and Conscious Monkeys Jun Toyohara 0 Kiichi Ishiwata 0 Muneyuki Sakata 0 Jin Wu 0 Shingo

RADIOLOGY

In vivo MR spectroscopy (MRS) provides information about metabolite concentrations in tissue. Recently, citrate (Cit) was detected by MRS in subgroups of pediatric brain tumors. Citrate is an intermediate in the tricarboxylic acid (TCA) cycle and accumulates in tissue when the glycolytic rate exceeds the TCA cycle activity, a feature of malignant tumors. Currently, no practical...