Table I.

Cell morphology and death on ePTFE immediately after 30-min thermal exposures. Cells were cultured on collagen-coated ePTFE at 37°C for a day, and then exposed to 37°(control), 45°, 47°and 50°C for 30 min. Next, they were stained with calcein AM (which labels the cytosol of viable cells, appearing green) and ethidium homodimer-1 (which labels the nuclei of dead cells, appearing red) for determining the morphology of viable cells and the percentage of dead cells. In general, as the temperature increased, the size (area and perimeter) of viable cells decreased and the percentage of dead cells increased.

Temperature (°C)	Area (μm2)	Perimeter (μm)	Roundness index	Cell death
37	871	158	0.55	3%
45	589*	109*	0.63*	10%*
47	452*	98*	0.60	19%*
50	488*	97*	0.66	75%*

^*P < 0.05 with respect to the 37°C/30-min exposure in the same column.