医療科学部

shirakawa seiji

  (白川 誠士)

Profile Information

Affiliation
Fujita Health University
Degree
博士(医学)

J-GLOBAL ID
200901005963740549
researchmap Member ID
1000254979

Research Interests

 3

Research Areas

 1

Papers

 23
  • Shohei Harada, Kazuki Takano, Motoaki Fukasawa, Seiji Shirakawa, Masayuki Yamada
    Magnetic resonance imaging, 94 89-97, Sep 9, 2022  
    PURPOSE: As we are exposed to stress on a daily basis, it is important to detect and treat stress during the subclinical period. However, methods to quantify and confirm stress are currently unavailable, and the detection of subclinical stressors is difficult. This study aimed to determine whether manganese-enhanced magnetic resonance imaging (MEMRI) could be used to assess stress in rat brains. METHODS: We exposed male Wistar/ST rats bred in a specific pathogen-free environment to ultrasound stimuli (22 kHz and 55 kHz) for 10 days and then assessed brain activities using MEMRI, the light/dark box test, and ΔFosB immunohistochemical staining. RESULTS: In the MEMRI assessments, exposure at 22 kHz activated the periaqueductal gray, while exposure at 55 kHz specifically enhanced activity in the nucleus accumbens core and the orbitofrontal cortex. The exploratory behavior of the 55-kHz group increased sharply, while that of the 22-kHz group showed a lower exploratory value. ΔFosB expression increased in the orbitofrontal cortex, nucleus accumbens, periaqueductal gray, and amygdaloid nucleus in the 22-kHz group. CONCLUSION: Ultrasound stimuli at 22 kHz suppressed weight gain in rats and excessive ΔFosB induction in the nucleus accumbens caused excessive sensitization of the neural circuit, thereby contributing to pathological behavior. We thus demonstrated that MEMRI can be useful to objectively assess the pathophysiology of stress-related disorders.
  • Masanori Tadokoro, Seiji Shirakawa, Masanori Watanabe, Atsushi Teramoto, Masaki Uno, Seiichiro Ota, Ryo Matsukiyo, Taro Okui, Yoshikazu Kobayashi, Hiroshi Toyama
    Physical and Engineering Sciences in Medicine., 44(2) 365-375, Feb, 2021  Peer-reviewed
  • 奥田光一, 野坂広樹, 伊東利宗, 松友紀和, 市川肇, 白川誠士, 山木範泰, 菊池明泰, 對間博之, Michael Ljungberg
    日本放射線技術学会雑誌, 77(1) 41-47, Jan, 2021  Peer-reviewed
  • Seiji Shirakawa, Kei Tsukamoto, Hiroyuki Azuma, Kazutaka Nakashima, Masakazu Tsujimoto, Kazuki Takano, Masayuki Yamada
    Nuclear medicine communications, 40(8) 792-801, Aug, 2019  Peer-reviewedLead author
    BACKGROUND: Single-photon emission computed tomography is a tomographic imaging method that acquires a projection image by rotating a gamma camera around by 380° or 180°. For myocardial single-photon emission computed tomography, 180° acquisition is common, but it has limitations including an incomplete reconstruction, which can distort the resulting image. It is possible to produce a complete reconstruction using 360° acquisition, but the testing time is long and is burdensome to patients. METHODS: The nonuniform sampling pitch acquisition (NUSPA) method devised in this study involves reducing the total sampling count using NUSPA that reduces the sampling pitch in the range in which the gamma cameras are closer to the myocardium (RAO45-LPO45) and increases it elsewhere. RESULTS AND CONCLUSION: The NUSPA-1 method based on a 6° sampling pitch had 20 views fewer than 360° acquisition. In addition, the NUSPA-2 method based on a 3.75° sampling pitch had 60 views fewer than 360° acquisition, considerably reducing the testing time. The acquired sinograms from the NUSPA methods were subjected to nonuniform rational B-spline surface interpolation processing, producing data with a uniform sampling pitch, after which image reconstruction was performed. The images after nonuniform rational B-spline interpolation for both the line sources and heart-liver phantom investigated in this study were not found to have the distortion observed from 180° acquisition or a count decrease at the center, resulting in image quality nearly equivalent to 360° acquisition. This method enabled a reduction in testing time without impacting image quality.
  • Kazuyuki Minami, Toshiyuki Ishida, Yasuki Asada, Seiji Shirakawa, Masanao Kobayashi, Shoichi Suzuki, Tomimasa Konishi, Hidenori Mimura
    Wiley Online Library, Jun, 2019  Peer-reviewed

Misc.

 3

Books and Other Publications

 4

Research Projects

 1

教育内容・方法の工夫(授業評価等を含む)

 1
  • 件名(英語)
    スライドを主体とした講義を行っているが、そのまま聞いているだけでは一方的な講義になってしまうため、重要な項目は空白にして、資料中に書き込むようにしてある。

作成した教科書、教材、参考書

 1
  • 件名(英語)
    スライドの内容を、重要な項目を空白にして配布している