Gh. Harrison et al., IN-VITRO ACTION OF CONTINUOUS-WAVE ULTRASOUND COMBINED WITH ADRIAMYCIN, X-RAYS OR HYPERTHERMIA, Radiation research, 145(1), 1996, pp. 98-101
We compared the ability of continuous-wave ultrasound to enhance cytot
oxicity from X irradiation, hyperthermia or exposure to adriamycin. Th
e survival of CHO cells exposed in culture medium to these agents was
determined with and without continuous-wave ultrasound (1.62 or 1.765
MHz). In water-filled transmission exposure vessels with 2-cm-diameter
Mylar end windows, 10-min insonation not producing cytotoxicity could
produce (OH)-O-. radicals (measured by electron paramagnetic resonanc
e) even at 0.4 W/cm(2), Ultrasound at intensities ranging between 1 an
d 2.5 W/cm(2) increased the clonogenic cytotoxicity of adriamycin (P =
0.0023 by paired t test) but not of X rays (2-10 Gy) or hyperthermia
(44 degrees C for 10-50 min). The only significant action of continuou
s-wave ultrasound under similar test conditions was the potentiation o
f adriamycin-induced clonogenic cytotoxicity, possibly mediated by cav
itational activity. (C) 1996 by Radiation Research Society