Biological dose estimation of UVA laser microirradiation utilizing charged particle-induced protein foci

Biological dose estimation of UVA laser microirradiation utilizing charged particle-induced protein foci.

The induction of localized DNA damage within a discrete nuclear volume is an important tool in DNA repair studies. Both charged particle irradiation and laser microirradiation (LMI) systems allow for such a localized damage induction, but the results obtained are difficult to compare, as the delivered laser dose cannot be measured directly. Therefore, we revisited the idea of a biological dosim...

Dynamics of DNA-repair factors and chromosomes studied by laser-UVA-microirradiation and laser-photobleaching

Detection of Laser-UV Microirradiation-induced DNA Photoiesions

A low-power laser-UV microbeam of wavelength 257 nm was used for microirradiation of a small part of the nucleus of Chinese hamster cells. Following fixation in interphflse or in the subsequent metaphase indirect immunofluorescent staining was performed with antiserum to photoproducts ofDNA treated with far UV ligh t. The results show that antibodies specific for UVirradiated DNA can be used fo...

Biological dose estimation for charged-particle therapy using an improved PHITS code coupled with a microdosimetric kinetic model.

Microdosimetric quantities such as lineal energy, y, are better indexes for expressing the RBE of HZE particles in comparison to LET. However, the use of microdosimetric quantities in computational dosimetry is severely limited because of the difficulty in calculating their probability densities in macroscopic matter. We therefore improved the particle transport simulation code PHITS, providing...

A new laser test stand for simulating charged-particle tracks

We report on the construction of a new laser test stand equipped with a 1064nm pulsed infrared YAG laser for simulating the passage of a charged particle in a silicon detector. The standard semiconductor repairing tool, the socalled laser-cutter, has been modified to have a newly developed optics which has the ability to reduce the light by the order of 106~108 and to adjust the spot size to se...