Article

Synergistic effects of local temperature enhancements on cellular responses in the context of high-intensity, ultrashort electric pulses

Department of Electrical and Computer Engineering and Frank Reidy Center for Bio-Electrics, Old Dominion University, Norfolk, VA 23529-0246, USA.
Medical & Biological Engineering (Impact Factor: 1.5). 02/2011; 49(6):713-8. DOI: 10.1007/s11517-011-0745-z
Source: PubMed

ABSTRACT Results of self-consistent analyses of cells show the possibility of temperature increases at membranes in response to a single nanosecond, high-voltage pulse, at least over small sections of the membrane. Molecular Dynamics simulations indicate that such a temperature increase could facilitate poration, which is one example of a bio-process at the plasma membrane. Our study thus suggests that the use of repetitive high-intensity voltage pulses could open up possibilities for a host of synergistic bio-responses involving both thermal and electrically driven phenomena.

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    • "Our findings suggest that whenever the pulse duration is small compared to the thermal relaxation constant of the cell membrane, and the membrane capacitance drops to its low asymptotic high-frequency value in the pulse spectral bands, one may observe a steep increase in the membrane temperature, up to physiologically significant levels , the average (cytoplasm) temperature remaining essentially unaffected. Similar conclusions were obtained in [14] following a more sophisticated approach which combines Smoluchowski equation to describe membrane response , the heat equation and molecular dynamics simulations , to gauge the impact of localized membrane heating on membrane poration. "
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