Abstract:
:The detection of free radical reactions in a gelatin sample irradiated by a heavy-ion beam was tested using electron paramagnetic resonance (EPR) spectroscopic and MRI methods. Geometry and the amount of free radical generation in a sample are described. A reaction mixture containing glutathione and a nitroxyl radical, TEMPOL, was caked with gelatin, and then irradiated with a 290 MeV carbon beam. The amount of free radical generation in a solid sample was almost flat from the surface to the beam end, except for a small peak, the peak radioactivation profile, and then steeply decreased approaching the beam end. Total free radical reactions obtained with carbon-beam irradiation were expected to be less than one-third of X-ray irradiation, when the same dose for a deeper target was considered. Both EPR and MRI are useful tools to visualize free radical generation in samples irradiated by a heavy-ion beam. The EPR-based method is more sensitive and quantitative than the MRI-based method; however, the MRI method can achieve high spatial resolution. This study gives the rationale for a redox regulation trial using antioxidant drugs to reduce the side effects on normal tissues in carbon-beam therapy.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Matsumoto K,Nagata K,Yamamoto H,Endo K,Anzai K,Aoki Idoi
10.1002/mrm.21958subject
Has Abstractpub_date
2009-05-01 00:00:00pages
1033-9issue
5eissn
0740-3194issn
1522-2594journal_volume
61pub_type
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