title: Ultrasound-induced light transmission change within platelet suspensions as an indirect measure of platelet morphology: preliminary correlation with stirring-induced light transmission change.
abstract: Discoid platelets were directionally orientated using stirring or ultrasound, and the change from random orientation was measured by light transmission. Stirring-induced light transmission change (SILTC), already well established as a good indirect indicator of platelet morphology, was compared with ultrasound-induced light transmission change (USILTC) in order to determine whether USILTC may be a similarly good indicator of platelet morphology. Numerous direct comparisons were made between SILTC and USILTC at various static temperatures, and during the dynamic thermal transitions of warming and cooling. Good correlation exists between quantitated SILTC and USILTC values, but the relationship is not exact. Furthermore, single stirring events may considerably distort the relationship under certain conditions. At the ultrasound frequency of 5 MHz and at an estimated peak positive pressure of 2.03 X 10(4) Pa, the USILTC response patterns exhibit a qualitative "spike" pattern for unfixed platelets, which disappears following glutaraldehyde fixation. These preliminary findings are described and discussed in detail, since they suggest that USILTC is a better index of platelet viability than SILTC, although much research is still required in this area.
mesh_terms: D055592:Biophysical Phenomena; D001703:Biophysics; D001792:Blood Platelets / Q000166:cytology / Q000502:physiology*; D001793:Blood Preservation; D002470:Cell Survival; D006801:Humans; D008027:Light; D008722:Methods; D013535:Suspensions; D013696:Temperature; D014465:Ultrasonics / Q000295:instrumentation
chemical_list: D013535:Suspensions