This application's long term objective is to determine the potential for diagnostic ultrasound to induce biological effects in mammalian tissues. To accomplish this objective, several approaches are proposed; 1) to determine for extra utero human placentas the size and quantily of gas nuclei and the ultrasound parameters (IM, frequency, prr) needed to activate the nuclei to acoustic cavities; 2) to determine (a) the role of intercellular space and gas in mediating acoustic cavitation in an in vitro multicellular tissue system (multicell spheroids), to measure the force requisite for bubble penetration of cells, (c) to determine whether acoustic cavitation occurs intracellularly; 3) to verify certain phenomenological reports regarding ultrasound-induced effects (sister chromatid exchanges, unscheduled DNA systhesis, cell transformation, multigeneration cell deformation) in certain in vitro systems and, if verified, to identify the physical mechanism of action causing the effects(s); 4) to investigate the postulate that at hyperthermic temperatures a non-cavitational, non-thermal ultrasound-induced mechanism is operative; and 5) to determine the most effective pulsing regimes (prr, frequency) for induction cavitation at ultrasound intensities (Im) comparable to those emitted by clinical diagnostic units. The results obtained should be directly relevant to assessments of the potential for diagnostic ultrasound to induce biological effects in human tissue. Because the proposed projects focus on understanding how certain effects in chemical, in vitro, and vivo mammalian systems are produced (i.e., mechanisms) the results from these areas may be extrapolated to broader question of health and safety from exposure to dignostic ultrasound.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
5R01CA039230-20
Application #
2089774
Study Section
Diagnostic Radiology Study Section (RNM)
Project Start
1985-09-01
Project End
1995-04-30
Budget Start
1994-05-01
Budget End
1995-04-30
Support Year
20
Fiscal Year
1994
Total Cost
Indirect Cost
Name
University of Rochester
Department
Physiology
Type
Schools of Dentistry
DUNS #
208469486
City
Rochester
State
NY
Country
United States
Zip Code
14627
Miller, M W; Sherman, T A; Brayman, A A (2000) Comparative sensitivity of human and bovine erythrocytes to sonolysis by 1-MHz ultrasound. Ultrasound Med Biol 26:1317-26
Miller, M W; Brayman, A A; Abramowicz, J S (1998) Obstetric ultrasonography: a biophysical consideration of patient safety--the ""rules"" have changed. Am J Obstet Gynecol 179:241-54
Brayman, A A; Strickler, P L; Luan, H et al. (1997) Hemolysis of 40% hematocrit, Albunex-supplemented human erythrocytes by pulsed ultrasound: frequency, acoustic pressure and pulse length dependence. Ultrasound Med Biol 23:1237-50
Brayman, A A; Azadniv, M; Miller, M W et al. (1996) Effect of static pressure on acoustic transmittance of Albunex microbubble suspensions. J Acoust Soc Am 99:2403-8
Brayman, A A; Azadniv, M; Cox, C et al. (1996) Hemolysis of albunex-supplemented, 40% hematocrit human erythrocytes in vitro by 1-MHz pulsed ultrasound: acoustic pressure and pulse length dependence. Ultrasound Med Biol 22:927-38
Brayman, A A; Church, C C; Miller, M W (1996) Re-evaluation of the concept that high cell concentrations ""protect"" cells in vitro from ultrasonically induced lysis. Ultrasound Med Biol 22:497-514
Vona, D F; Miller, M W; Maillie, H D et al. (1995) A test of the hypothesis that cavitation at the focal area of an extracorporeal shock wave lithotripter produces far ultraviolet and soft x-ray emissions. J Acoust Soc Am 98:706-11
Brayman, A A; Miller, M W (1994) Ultrasonic cell lysis in vitro upon fractional, discontinuous exposure vessel rotation. J Acoust Soc Am 95:3666-8
Brayman, A A; Azadniv, M; Miller, M W et al. (1994) Bubble recycling and ultrasonic cell lysis in a stationary exposure vessel. J Acoust Soc Am 96:627-33
del Cerro, M; Child, S Z; Raeman, C H et al. (1994) A test of the hypothesis that diagnostic ultrasound disrupts myelination in neonatal rats. Ultrasound Med Biol 20:981-6

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