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Etsuro Mori

Possible papers associated with this exact author name in Arrow. This page groups case-insensitive exact name matches and is not a full identity disambiguation profile.

4 papers

1 author row

YNICL Journal 2021 Journal Article

Impaired perception of illusory contours and cortical hypometabolism in patients with Parkinson’s disease

Toshiyuki Ishioka
Kazumi Hirayama
Yoshiyuki Hosokai
Atsushi Takeda
Kyoko Suzuki
Yoshiyuki Nishio
Yoichi Sawada
Nobuhito Abe

F-fluorodeoxyglucose positron emission tomography (FDG-PET) to measure regional cerebral glucose metabolism in PD patients. Although there were no significant differences in the stimulus durations required for perception of illusory contours formed by aligned line ends between PD patients and controls, PD patients required significantly longer stimulus durations for the perception of Kanizsa illusory figures. Difficulty in perceiving Kanizsa illusory figures was correlated with hypometabolism in the higher-order visual cortical areas, including the posterior inferior temporal gyrus. These findings indicate an association between dysfunction in the posterior inferior temporal gyrus, a region corresponding to a portion of the LOC, and impaired perception of Kanizsa illusory figures in PD patients.

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YNICL Journal 2019 Journal Article

APOE-MS4A genetic interactions are associated with executive dysfunction and network abnormality in clinically mild Alzheimer's disease

Ya-Ting Chang
Etsuro Mori
Maki Suzuki
Manabu Ikeda
Chi-Wei Huang
Jun-Jun Lee
Wen-Neng Chang
Chiung-Chih Chang

PURPOSE OF THE RESEARCH: Although single nucleotide polymorphisms of membrane-spanning 4A (MS4A) (rs670139) and several other susceptibility genes have shown interaction effects on the risk of Alzheimer's disease (AD), little is known about the interaction effects of apolipoprotein E (APOE) with MS4A (rs670139) on cognitive performances, and the underlying pathogenesis is unclear. The study aimed to investigate the APOE-MS4A (rs670139) interaction effects on cognitive performances, cortical volumes, and functional connectivity (FC) in brain networks. PRINCIPAL RESULTS: Cognitive performances were characterized in each genotypic group, and were compared between normal controls and patients in each genotypic group. APOE-MS4A interaction effects on memory and executive function scores, cortical volumes, and FC in brain networks were demonstrated. Significant effects of APOE-MS4A interactions on FC were observed in executive control network (ECN) (T maxima = 4.99, false discovery rate-corrected p < .001), the calculation score (F3, 87 = 6.218; p = .015), and the volume in prefrontal (F3, 87 = 4.374; p = .039) and orbitofrontal cortices (F3, 87 = 6.022; p = .016). The calculation score was correlated with each frontal volume (cc) (ρ = 0.304; p = .004) and genetic interaction-associated FC in ECN (ρ = 0.282; p = .008). Variations in genotypes affected the relationship between the calculation score and each frontal volume (cc). MAJOR CONCLUSIONS: These findings indicate that the genetic interaction effects on FC in ECN might contribute to pathogenic mechanisms underlying the interaction effects of APOE-MS4A on calculation ability in AD.

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YNIMG Journal 2009 Journal Article

Quantitative analysis of donepezil binding to acetylcholinesterase using positron emission tomography and [5-11C-methoxy]donepezil

Kotaro Hiraoka
Nobuyuki Okamura
Yoshihito Funaki
Shoichi Watanuki
Manabu Tashiro
Motohisa Kato
Akiko Hayashi
Yoshiyuki Hosokai

The aim of this study was to establish kinetic analysis of [5-11C-methoxy]donepezil ([11C]donepezil), which was developed for the in-vivo visualization of donepezil binding to acetylcholinesterase (AChE) using positron emission tomography (PET). Donepezil is an AChE inhibitor that is widely prescribed to ameliorate the cognitive impairment of patients with dementia. Six healthy subjects took part in a dynamic study involving a 60-min PET scan after intravenous injection of [11C]donepezil. The total distribution volume (tDV) of [11C]donepezil was quantified by compartmental kinetic analysis and Logan graphical analysis. A one-tissue compartment model (1TCM) and a two-tissue compartment model (2TCM) were applied in the kinetic analysis. Goodness of fit was assessed with χ 2 criterion and Akaike's Information Criterion (AIC). Compared with a 1TCM, goodness of fit was significantly improved by a 2TCM. The tDVs provided by Logan graphical analysis were slightly lower than those provided by a 2TCM. The rank order of the mean tDVs in 10 regions was in line with the AChE activity reported in a previous post-mortem study. Logan graphical analysis generated voxel-wise images of tDV, revealing the overall distribution pattern of AChE in individual brains. Significant correlation was observed between tDVs calculated with and without metabolite correction for plasma time–activity curves, indicating that metabolite correction could be omitted. In conclusion, this method enables quantitative analysis of AChE and direct investigation of the pharmacokinetics of donepezil in the human brain.

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YNIMG Journal 2007 Journal Article

Reactivation of medial temporal lobe and occipital lobe during the retrieval of color information: A positron emission tomography study

Aya Ueno
Nobuhito Abe
Maki Suzuki
Kazumi Hirayama
Etsuro Mori
Manabu Tashiro
Masatoshi Itoh
Toshikatsu Fujii

It is widely accepted that memory traces of an event include various types of information about the content of the event and about the circumstances in which the individual experienced it. However, how these various types of information are stored and later retrieved is poorly understood. One hypothesis postulates that the retrieval of specific event information reactivates regions that were active during the encoding of this information, with the aid of binding functions of the medial temporal lobe (MTL) structures. We used positron emission tomography to identify the brain regions related to the encoding and retrieval of color information. Specifically, we assessed whether overlapping activity was found in both the MTL structures and color-related cortical regions during the encoding and retrieval of color information attached with meaningless shapes. During the study, subjects were asked to encode colored (red or green) and achromatic random shapes. At subsequent testing, subjects were presented with only achromatic shapes, which had been presented with or without colors during encoding, and were engaged in retrieval tasks of shapes and colors. Overlapping activity was found in the MTL and occipital lobe (the lingual and inferior occipital gyri) in the right hemisphere during the encoding and retrieval of meaningless shapes with color information compared with those without color information. Although there are some limitations to be considered, the present findings seem to support the view that the retrieval of specific event information is associated with reactivation of both the MTL structures and the regions involved during encoding of the information.

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