software (Minitube of America, Verona, WI) on images
obtained by a digital camera attached to phase contrast
microscope (Model BX41; Olympus Optical; Tokyo, Japan).
Prior to analysis, 500 L from each sample was diluted with
500 L of Androhep extender and incubated at 37 ◦C for
30 minutes. Five microscopic fields were analyzed for each
sample, in duplicate, for a total of ten fields or approximately
250–400 total cells per sample.