Comparative study of kinetics on DNA double-strand break induced by photo- and gamma-irradiation: Protective effect of water-soluble flavonoids
The double-strand break of DNA induced by visible light and γ-rays was studied through a single-molecule observation using fluorescence microscopy. We evaluated the protective effects of water-soluble derivatives of flavonoids, α-glucosyl hesperidin (αG-HSP) and α-glucosyl rutin (αG-rutin) in a quantitative manner. With regard to photo-induced damage, αG-rutin was found to provide twice as much protection as αG-HSP, whereas the protective effect of αG-rutin against γ-ray irradiation was comparable with that of αG-HSP. This observation demonstrates the dependence of the antioxidant potentials of these compounds on the source of irradiation.
Abstract A new technique is being developed at Argonne National Laboratory to produce a beam of polarized deuterium atoms. A part of the apparatus consists of a small cell which contains potassium vapor. The potassium atoms are polarized by circularly polarized light from a high-power cw laser. A port feeds deuterium into the cell and the polarization of the potassium is transferred to the deuterium by spin-exchange scattering. It is important that the potassium and deuterium atoms do not lose polarization by scattering from the walls of the exchange cell. We have tried various coatings of the exchange walls in order to inhibit losses from spin relaxation. Methods used to produce these coatings as well as their success will be described.