Thermal (heat) shock biothermomechanical viewpoint.

Thermal (or heat) shock phenomena have been observed in all organisms at the cellular level. They cause an acceleration in the rate of expression of specific genes (heat shock genes), resulting in an increase and accumulation of heat shock proteins in cells. The purpose of this study is to investigate the mechanisms of thermal shock from two different viewpoints: biothermal and biothermomechanical aspects. The former predicts more severe consequences on cells that the latter, whose thermal wave fronts are smoothed due to the coupling effects of thermoelasticity. In conclusion, it is the thermal wave propagation (the so-called "second sound" effect) which triggers a perturbation of normal gene expression. Thermotolerance is found to be inherited in the heat flux equation of the thermal wave model. The information obtained from this study can also be useful to therapeutical hyperthermia, preservation of organs and tissues, and laser and cryogenic surgery.