Ultrasonic comparison of two morphologically distinct melanosomes in malignant melanomas

Summary Ultrasonic measurement (0.333–200 MHz) of melanosomes isolated from B16 and Harding Passey (HP) mouse melanomas indicates that the partial wave resonance and principal relaxation of the 2 kinds of melanosomes are similar, but that their stochastic resonance is markedly different. The structure of the melanosomes appears basically amorphous, but linearly ordered and copolymeric in the molecular dimension of a segment composed of 5–6 zigzag units, which are packed closely in B16 and more openly in HP.Acknowledgment. This study was supported by Grants-in-Aid for Cancer Research, No. 580010030, No. 5839016 and No. 58480265, from the Ministry of Education, Science and Culture, by the Japan Ol'early Foundation and by the Alfred-Marchionini Foundation.