臨床医工学分野

Kazunori Kawaguchi

  (川口 和紀)

Profile Information

Affiliation
Assistant Professor, School of Health Sciences Faculty of Clinical Engineering, Fujita Health University
Degree
博士(医学)

J-GLOBAL ID
201501002916890019
researchmap Member ID
7000013058

Papers

 14
  • 蔦村 琴子, 大橋 篤, 細江 眞生, 高須 立平, 石田 大賀, 新 典雄, 堀 秀生, 井平 勝, 川口 和紀, 中井 滋, 長谷川 みどり, 坪井 直毅
    日本透析医学会雑誌, 56(Suppl.1) 475-475, May, 2023  
  • Midori Hasegawa, Nobuya Kitaguchi, Hajime Takechi, Kazunori Kawaguchi, Kengo Ito, Takashi Kato, Masao Kato, Norio Nii, Sachie Yamada, Atsushi Ohashi, Shigehisa Koide, Hiroki Hayashi, Kazuo Takahashi, Daijo Inaguma, Yukio Yuzawa, Naotake Tsuboi
    Therapeutic Apheresis and Dialysis, 26(3) 529-536, Jun, 2022  
  • Yuta Saito, Miwa Sakata, Moe Kobayakawa, Hiroshi Kawachi, Kazunori Kawaguchi, Yoshiyuki Hiki, Masao Kato, Mayuko Mori, Midori Hasegawa, Norimi Ohashi, Yukio Yuzawa, Nobuya Kitaguchi
    Neuropsychiatric Disease and Treatment, 16 607-627, 2020  
    Purpose: Amyloid-β protein (Aβ) is one of the causative proteins of Alzheimer’s disease. We have been developing extracorporeal blood Aβ-removal systems as a method for enhancing Aβ clearance from the brain. We reported previously that medical adsorbents and hemodialyzers removed Aβ monomers from peripheral blood, which was associated with influx of Aβ monomers from the brain into the bloodstream. Our intent here was to develop a method to promote clearance of Aβ oligomers and to provide an estimate of the molecular size of intact Aβ oligomers in plasma. Methods: Two hollow-fiber devices with different pore sizes (Membranes A and B) were evaluated as removers of Aβ oligomers with human plasma in vitro. The concomitant removal of Aβ oligomers and monomers was investigated by using Membrane B and hexadecyl alkylated cellulose beads or polysulfone hemodialyzers. Double-filtration plasma-pheresis with Membrane A was investigated as an approach for the removal of plasma Aβ oligomers in humans. Results: Aβ oligomers were effectively removed by both Membranes A and B. The increase of Aβ oligomers in plasma was observed just after the removal of plasma Aβ oligomers in humans. The intact molecular size of major Aβ oligomers in the plasma was estimated to be larger than albumin at approximately 60 kDa or more. Additionally, the concomitant removal of Aβ monomers and oligomers evoked dissociation of larger Aβ oligomers into smaller ones and monomers. Conclusion: Aβ oligomers were cleared from plasma both in vitro and in human subjects by using hollow-fiber membranes with large pores, indicating that their intact sizes were mostly larger than 60 kDa. Aβ oligomers in peripheral circulation were increased after some clearances in human. Further investigation will determine whether the Aβ oligomers detected in circulation after clearance were via influx from the brain.
  • Nobuya Kitaguchi, Harutsugu Tatebe, Kazuyoshi Sakai, Kazunori Kawaguchi, Shinji Matsunaga, Tomoko Kitajima, Hiroshi Tomizawa, Masao Kato, Satoshi Sugiyama, Nobuo Suzuki, Masao Mizuno, Hajime Takechi, Shigeru Nakai, Yoshiyuki Hiki, Hiroko Kushimoto, Midori Hasegawa, Yukio Yuzawa, Takahiko Tokuda
    Journal of Alzheimer's disease : JAD, 69(3) 687-707, 2019  Peer-reviewed
    The accumulation of amyloid-β protein (Aβ) and tau in the brain is a major pathological change related to Alzheimer's disease. We have continued to develop Extracorporeal Blood Aβ Removal Systems (E-BARS) as a method for enhancing Aβ clearance from the brain. Our previous report revealed that dialyzers effectively remove blood Aβ and evoke large Aβ influxes into the blood, resulting in a decrease in brain Aβ accumulation after initiating hemodialysis, and that patients who underwent hemodialysis had lower brain Aβ accumulation than those who did not. Here, plasma total tau concentrations from 30 patients undergoing hemodialysis were measured using an ultrasensitive immunoassay and compared to those from 11 age-matched controls. Plasma total tau concentrations were higher in patients with renal failure regardless of whether they underwent hemodialysis, suggesting the involvement of the kidneys in tau degradation and excretion. Hemodialyzers effectively removed blood Aβ but not extracorporeal blood tau. The influx of tau into the blood was observed at around the 1 h period during hemodialysis sessions. However, the influx amount of tau was far smaller than that of Aβ. Furthermore, histopathological analysis revealed similar, not significantly less, cerebral cortex phosphorylated tau accumulation between the 17 patients who underwent hemodialysis and the 16 age-matched subjects who did not, although both groups showed sparse accumulation. These findings suggest that hemodialysis may induce both tau and Aβ migration into the blood. However, as a therapeutic strategy for Alzheimer's disease, it may only be effective for removing Aβ from the brain.
  • Kitaguchi N, Kawaguchi K, Yamazaki K, Kawachi H, Sakata M, Kaneko M, Kato M, Sakai K, Ohashi N, Hasegawa M, Hiki Y, Yuzawa Y
    Journal of artificial organs : the official journal of the Japanese Society for Artificial Organs, 21(2) 220-229, Jun, 2018  Peer-reviewed

Misc.

 45

Research Projects

 6