Grant-in-Aid for Scientific Research (B)
|Allocation Type||Single-year Grants|
Biomedical engineering/Biological material science
|Research Institution||YAMAGATA UNIVERSITY|
KOSAWADA Tadashi Mechanical Systems Engineering, Yamagata University, Associate Professor, 工学部, 助教授 (10143083)
IIJAMA Yoshiaki School of Medicine, Yamagata University, Research Associate, 医学部, 助手 (90241710)
NAKADA Teruhiko School of Medicine, Yamagata University, Professor, 医学部, 教授 (50009495)
KUBOTA Yohko School of Medicine, Yamagata University, Associate Professor, 医学部, 助教授 (60125763)
|Project Period (FY)
1997 – 1999
Completed(Fiscal Year 1999)
|Budget Amount *help
¥8,800,000 (Direct Cost : ¥8,800,000)
Fiscal Year 1999 : ¥1,400,000 (Direct Cost : ¥1,400,000)
Fiscal Year 1998 : ¥3,300,000 (Direct Cost : ¥3,300,000)
Fiscal Year 1997 : ¥4,100,000 (Direct Cost : ¥4,100,000)
|Keywords||Vesicular Transport / Simulator / Bio-membrane / large Deformation Analysis / Analytical Method / Finite Element Method / Chained Vesicles / Outer Surrounding Cytoplasmic Membrane / 細胞内輸送 / 膜小胞 / 細胞移動 / リポゾーム|
A simulator for vesicular transport in cells was developed based on recent knowledge of molecular biology of the cell. Analytical method as well as finite element method were utilized to achieve the goal.
1. Simulation of vesicular transport based on the analytical method
(1) When the opening perimeter of a spherical membrane shell is unfolded with its perimeter kept parallel to its axis, there exists several points where the shapes and the tensions change significantly with slight changes of the opening radius. This is considered to be the bucking-like phenomena of the membrane with a spontaneous curvature.
(2) In the repeating units of chained vesicles, it is found that the cylindrical tube shape and the hourglass shape are stable with respect to energy.
(3) It is theoretically suggested that the chained vesicles and the cylindrical channel derived from the chained vesicles are some of the stable shapes with respect to energy and can potentially be formed and presented in the vascular en
(4) The computed shape suggests that the effects of in-plane shear elasticity and outer surrounding cytoplasmic membrane are significant and these should be taken into account in theoretical analysis.
(5) The chained vesicle changes its shape dramatically even when the opening radius slightly increases from the starting shape. The jump-like phenomena of strain energy was often observed where each constriction disappears.
2. Development of the specific finite element method for vesicular transport simulator by utilizing Mathematica
(1) Formulation of the finite element method was developed based on elastic potential energy function. The requirement of constant surface area of the membrane was satisfied by implementing additional surface pressure.
(2) The requirement of constant surface area of the membrane has significant effect on deformed shape of the vesicle.
(3) Mooney-Rivlin type strain energy density function, which was developed for rubber red cell model, was utilized. The computed cortical tension was given as 0.003-0.18 dyn/cm. This results support the know experimental data of 0.03 dyn/cm. Less