38 research outputs found
Use of positron emission tomography for real-time imaging of biodistribution of green tea catechin.
The aim of this study was to achieve real-time imaging of the in vivo behavior of a green tea polyphenol, catechin, by positron emission tomography (PET). Positron-labeled 4″ -[(11)C]methyl-epigallocatechin gallate ([(11)C]Me-EGCG) was orally administered to rats, and its biodistribution was imaged for 60 min by using a small animal PET system. As the result, images of [(11)C]Me-EGCG passing through the stomach into the small intestines were observed; and a portion of it was quantitatively detected in the liver. On the other hand, intravenous injection of [(11)C]Me-EGCG resulted in a temporal accumulation of the labeled catechin in the liver, after which almost all of it was transferred to the small intestines within 60 min. In the present study, we succeeded in obtaining real-time imaging of the absorption and biodistribution of [(11)C]Me-EGCG with a PET system
Introduction of a Genetic Algorithm to a Mass-Consistent Model
The purpose of this study is to examine the retardation of the settling velocity of a particle in the turbulent flow generated by an oscillating grid through a numerical simulation and a hydraulic experiment. First, we measured trajectories of glass beads in a grid-generated turbulence to verify the validity of the numerical simulation for particle behavior. Next, we examined the dynamic response of particles utilizing wavelet analysis and the relationship between the retardation of the mean settling velocity and the turbulent characteristic. As a result, we could identify low-frequency components that particles would easily follow, and high frequency components that would affect the motion of particles in vertical fluid velocity fluctuations, respectively. Furthermore, it was found that the retardation of the mean settling velocity depends on the spectral distribution of high-frequency, and that the retardation rates increase with increases in turbulent intensity