Exposure of Deinococcus radiodurans to both static magnetic fields and gamma radiation: observation of cell recuperation effects.

The extremophilic bacterium Deinococcus radiodurans displays an extraordinary ability to withstand lethal radiation effects, due to its complex mechanisms for both proteome radiation protection and DNA repair. Published results obtained recently at this laboratory show that D. radiodurans submitted to ionizing radiation results in its DNA being shattered into small fragments which, when exposed to a "static electric field' (SEF), greatly decreases cell viability.

DNA fragmentation by gamma radiation and electron beams using atomic force microscopy.

Double-stranded pBS plasmid DNA was irradiated with gamma rays at doses ranging from 1 to 12 kGy and electron beams from 1 to 10 kGy. Fragment-size distributions were determined by direct visualization, using atomic force microscopy with nanometer-resolution operating in non-tapping mode, combined with an improved methodology. The fragment distributions from irradiation with gamma rays revealed discrete-like patterns at all doses, suggesting that these patterns are modulated by the base pair composition of the plasmid.

Cell cycle arrest, extracellular matrix changes and intrinsic apoptosis in human melanoma cells are induced by Boron Neutron Capture Therapy.

Boron Neutron Capture Therapy (BNCT) involves the selective accumulation of boron carriers in tumor tissue followed by irradiation with a thermal or epithermal neutron beam. This therapy is therefore a cellular irradiation suited to treat tumors that have infiltrated into healthy tissues. BNCT has been used clinically to treat patients with cutaneous melanomas which have a high mortality.

Boron uptake in normal melanocytes and melanoma cells and boron biodistribution study in mice bearing B16F10 melanoma for boron neutron capture therapy.

Information on (10)B distribution in normal tissues is crucial to any further development of boron neutron capture therapy (BNCT). The goal of this study was to investigate the in vitro and in vivo boron biodistribution in B16F10 murine melanoma and normal tissues as a model for human melanoma treatment by a simple and rapid colorimetric method, which was validated by HR-ICP-MS. The B16F10 melanoma cell line showed higher melanin content than human melanocytes, demonstrating a greater potential for boronophenylalanine uptake.

Static electric fields interfere in the viability of cells exposed to ionising radiation.

Purpose: The interference of electric fields (EF) with biological processes is an issue of considerable interest. No studies have as yet been reported on the combined effect of EF plus ionising radiation. Here we report studies on this combined effect using the prokaryote Microcystis panniformis, the eukaryote Candida albicans and human cells.