A method for direct cell-to-cell binding has high potential to make reconstituted tissues and organs for pharmacological applications and regenerative medicine. It may be possible to produce unique materials and devices, which are based on biological properties by arranging cells appropriately. In addition, an ambitious study might lead to the construction of “multicellular artificial life” by assembling single cells. In this report we show a technology to attach cells to each other rapidly to make heterogeneous multicellular spheroids and minutely arranged cell-based micro tissues.
Blood vessels are able to expand in order to let more blood .ow through them, as well as contract to help control the .ow of blood. Fluid-Structure Interaction (FSI) modeling simulates this process of expansion and contraction for more accurate results. The results of two analyses, namely the Fluid and FSI, are presented to compare a difference between the rigid and deformable walls, respectively. In the FSI analysis, strong coupling method (direct method) is used to solve the fundamental descretized equations to satisfy the geometrical compatibility and the equilibrium conditions on the interface between the .uid, representing the blood .ow, and the hyper-elastic structure, representing the vascular tissue. A high order Mooney-Rivlin material is used to model the vascular tissue. Automatic mesh update method is adjusting the .uid mesh under the defor-mation of the structure domain along the time. Peripheral vessels network is applied as out.ow boundary condition to the 3D Fluid and FSI simulations. The peripheral network is modeled as a binary symmetric tree attached to the outlet(s) of the 3D model. The small arteries are modeled us-ing 1D scheme, while the arterioles and capilaries are modeled using the structure tree impedance (STI) model. The coupling of the 3D Fluid-Structure .nite element model and the multi-scale model (1D -0D) facilitates the use of more realistic boundary conditions leading to more accurate information on the hemodynamic factors, e.g. wall shear stress (WSS). As, for example, low den-sity lipoprotein tends to deposit in the areas of blood vessels with low WSS. The degeneration of blood vessel walls is often initiated by hemodynamic forces, thus it is valuable to obtain the infor-mation on these factors for accurate prevention and prognosis of diseases such as atherosclerosis or middle cerebral aneurysm. [This abstract is not included in the PDF]
A microheater device which can culture and locally heat cell population in an incubator was fabricated by the MEMS process. Temperatures in minute areas on the device were acquired by the fluorescent thermometry in liquid and the heating simulation based on the finite element method, also its transient phenomenon was measured by the thermal infrared microscopy. On the cell heating experiment, cells were cultured and heated on the device. As a result, it is shown that it may induce heat shock response to cells at single cell level and may possibly ascertain the heat shock protein expression induced by the cell-to-cell communication, which has not observed yet. [This abstract is not included in the PDF]
Some water in tissues or foods has different characteristics from pure water due to the strong interaction with biomolecules. This water, bound water, stabilizes and prevents biomolecules from degradation. In this study, the dielectric spectra of porcine gelatin-gel containing various amount of water were measured. Dielectric strength, bound water ratio and the distribution function of relaxation time of bound water were calculated using the measured dielectric spectra. In addition, water activity and frozen water ratio were measured by a water activity meter and Differential Scanning Calorimetry (DSC). Two types of dielectric relaxation were found, whose relaxation times are 10~100 times longer than pure water. [This abstract is not included in the PDF]
In this paper, we proposed a microfluidic device for formation of steady artificial cell membrane (lipid bilayer membrane) and electrical recordings of transmembrane currents. Lipid bilayer membrane is able to form by a sequential injection of aqueous buffer and lipid at the device. We proposed that microchambers within the device were electrically connected through a gold-pattern and a circular channel that are integrated for the detection of electrical signals. In addition, we developed a glass microfluidic device targetting for long-term stability of formed bilayer membranes. By the practical use this device we proposed, it is expected to lower the analysis cost and enhance the throughput of the function measurement of the membrane protein which related to the drug development. [This abstract is not included in the PDF]
We review recent progress in mathematical study on hematopoietic stem cells. This review paper deals with theoretical investigations for two major issues on basic and clinical hematology: “disorder of homeostasis in hematopoiesis” and “transplantation of hematopoietic stem cells”. Several mathematical models are introduced to describe self-renewal and differentiation of hematopoietic stem cells. Finally, future potential applications of mathematical study to regenerative medicine and cancer treatment are discussed.