Radiobiological investigations at tumor cell lines by exploiting chrono-biological aspects of chronological dose distributions

W. Ulmer

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arXiv · 1111.6811

Radiobiological investigations at tumor cell lines by exploiting chrono-biological aspects of chronological dose distributions

W. Ulmer

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Abstract

Using 31P-NMR spectroscopy the chronological behavior of the ATP-metabolism of the tumor spheroids C3H-MA, 9L-Gliome and the mono-layer L1210 has been analyzed via decrease of the {\beta}-peak. All three cell lines show characteristic periods, and a homeostatic control cannot be recognized. Essential components of these periods are circadian (i.e. one day), circa-semiseptan (i.e. 3.5 days) and circa-septan (i.e. one week). The determination of the survival fractions provides an optimum exploitation of radiation damages, when the ATP-concentration assumes a maximum value. This optimum is reached, when all three cycles exhibit the ATP maximum, which is only possible by accounting for the circa-septan rhythm. The goal of this study is to elaborate an optimal fractionation scheme with regard to the irradiation of tumors.

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W. Ulmer. 2011-11-29. Radiobiological investigations at tumor cell lines by exploiting chrono-biological aspects of chronological dose distributions. https://arxiv.org/abs/1111.6811

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