| Project/Area Number |
11834005
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Institution | UNIVERSITY OF TOKYO |
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Principal Investigator |
IWASAKA Masakazu UNIVERSITY OF TOKYO, GRADUATE SCHOOL OF MEDICINE, LECTURER, 大学院・医学系研究科, 講師 (90243922)
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| Co-Investigator(Kenkyū-buntansha) |
SHIBATA Masahiro UNIVERSITY OF TOKYO, GRADUATE SCHOOL OF MEDICINE, LECTURER, 大学院・医学系研究科, 講師 (60158954)
上野 照剛 東京大学, 大学院・医学系研究科, 教授 (00037988)
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| Project Period (FY) |
1999 – 2000
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| Project Status |
Completed (Fiscal Year 2000)
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| Budget Amount *help |
¥4,100,000 (Direct Cost: ¥4,100,000)
Fiscal Year 2000: ¥1,100,000 (Direct Cost: ¥1,100,000)
Fiscal Year 1999: ¥3,000,000 (Direct Cost: ¥3,000,000)
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| Keywords | Magnetic field effect / Enzymatic reaction / Protein / Cellular morphology / Magnetic orientation / Diamagnetism / Platelet aggregation / Hemoglobin / 強磁場影響 / カタラーゼ / 生体高分子 / フィブリン / 血小板 / 赤血球 |
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| Research Abstract |
Real-time optical measurements of a red blood cell (RBC) suspension and a hemoglobin solution were carried out under magnetic fields of Tesla order. The optical absorbance spectrum of oxyhemoglobin had two peaks in the range of 500 nm to 600 mn. The absorbance peak at 575 mn increased by 19% more than the peak at 540 mn under magnetic fields of 8 T.The results indicate that strong magnetic fields do not have any effect on the conformation of hemoglobin, but rather, magnetic fields affect the intracellular hemoglobin conformation.
To investigate the possible effect of magnetic field on an enzymatic activity, a catalase-immobilized platinum black electrode was used to measure the catalytic decomposition of hydrogen peroxide by catalase. The sensor's current changed in correspondence with the varying magnetic fields. During the magnetic field exposures, the electrode's current increased nearly 200%. The clear and reproducible increase in the electrode's current under magnetic fields indicated that the catalytic activity of catalase was disturbed under magnetic field exposure of up to 8 T and at a threshold between 1 to 2 T.
Also, we exhibited the orientation of smooth muscle cells, which were embedded on magnetically oriented collagen gel. Not using collagen guidance , we firstly observed a novel phenomenon of adherent smooth muscle cell on a plastic surface directing its long axis along static high magnetic fields. The smooth muscle cell domain ordered within 40 hours by 14 tesla, and increasing initial cell density resulted in a complete uniaxial ordering, which was resembled to the magnetic orientation of collagen and fibrin fibers.
Furthermore, an enhanced aggregation of blood platelet under 8 T magnetic field was observed. The diamagnetic torque force acting on the cell membrane was responsible for the effect.
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