title: Acoustic Impedance Analysis with High-Frequency Ultrasound for Identification of Fatty Acid Species in the Liver.
abstract: Acoustic properties of free fatty acids present in the liver were studied as a possible basis for non-invasive ultrasonic diagnosis of non-alcoholic steatohepatitis. Acoustic impedance was measured for the following types of tissue samples: Four pathologic types of mouse liver, five kinds of FFAs in solvent and five kinds of FFAs in cultured Huh-7 cells. A transducer with an 80-MHz center frequency was incorporated into a scanning acoustic microscopy system. Acoustic impedance was calculated from the amplitude of the signal reflected from the specimen surface. The Kruskal-Wallis test revealed statistically significant differences (p < 0.01) in acoustic impedance not only among pathologic types, but also among the FFAs in solvent and in cultured Huh-7 cells. These results suggest that each of the FFAs, especially palmitate, oleate and palmitoleate acid, can be distinguished from each other, regardless of whether they were in solution or absorbed by cells.
authors.affiliation: Graduate School of Engineering, Chiba University, Inage, Chiba, Chiba, Japan. Electronic address: k_ito@chiba-u.jp.
authors.forename: Kazuyo
authors.initials: K
authors.lastname: Ito
authors.affiliation: Center for Frontier Medical Engineering, Chiba University, Inage, Chiba, Chiba, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Yoshida
authors.affiliation: Graduate School of Medicine, Chiba University, Chuou, Chiba, Chiba, Japan.
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Maruyama
authors.affiliation: F. L. Lizzi Center for Biomedical Engineering, Riverside Research Institute, New York, New York, USA.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Mamou
authors.affiliation: Center for Frontier Medical Engineering, Chiba University, Inage, Chiba, Chiba, Japan.
authors.forename: Tadashi
authors.initials: T
authors.lastname: Yamaguchi
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D004195:Disease Models, Animal; D017097:Electric Impedance; D005227:Fatty Acids / Q000378:metabolism*; D008099:Liver / Q000000981:diagnostic imaging / Q000378:metabolism*; D051379:Mice; D065626:Non-alcoholic Fatty Liver Disease / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000378:metabolism*; D014463:Ultrasonography / Q000379:methods*
chemical_list: D005227:Fatty Acids
keywords: Acoustic impedance; Free fatty acid; Lipid droplet; Liver; Non-alcoholic steatohepatitis; Scanning acoustic microscopy