KINDAI UNIVERSITY


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FUKUDA Makoto

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FacultyDepartment of Biomedical Engineering / Graduate School of Biology-Oriented Science and Technology
PositionAssociate Professor
Degree
Commentator Guidehttps://www.kindai.ac.jp/meikan/1248-fukuda-makoto.html
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Last Updated :2020/09/30

Education and Career

Education

  •  - 1993 , Waseda University
  •  - 1991 , Waseda University, School of Science and Engineering

Academic & Professional Experience

  •   2014 04 ,  - 現在, Faculty of Biology-Oriented Science and Technology, Department of Biomedical Engineering, Kindai University

Research Activities

Published Papers

  • Impact of three-dimensional tortuous pore structure on polyethersulfone membrane morphology and mass transfer properties from a manufacturing perspective., Fukuda M, Saomoto H, Mori T, Yoshimoto H, Kusumi R, Sakai K, Journal of artificial organs : the official journal of the Japanese Society for Artificial Organs, Journal of artificial organs : the official journal of the Japanese Society for Artificial Organs, Nov. 2019 , Refereed
  • Observation and proposed measurements of three-dimensional tortuous capillary pores with depth for hollow fiber hemoconcentrator membrane using dynamic force microscopy, Makoto Fukuda, Hitoshi Saomoto, Taisei Shimizu, Koki Namekawa, Kiyotaka Sakai, Advanced Biomedical Engineering, Advanced Biomedical Engineering, 8, 145 - 152, Jun. 2019 , Refereed
    Summary:© 2019, Japanese Society for Medical and Biological Engineering. All rights reserved. A hemoconcentrator is installed as a part of cardiopulmonary bypass to concentrate the blood by removing excess water and unnecessary electrolytes from the blood diluted with myocardial protection fluid. The hemoconcentrator must remove water from diluted blood efficiently and quickly and remove proinflamma-tory cytokines and other unwanted molecules, without losing useful proteins such as albumin. Especially, the pore diameter and diameter distribution of the innermost surface greatly affect the pure water permeability and sieving coefficient of the solutes. In this study, the pore structure of the inner surface of the membrane was observed, and pore measurement of hollow fiber hemoconcentrator membranes was attempted using a scanning probe microscope (SPM). The samples studied were commercially available hemoconcentrator membranes PUREMA A and B (JMS Co. Ltd., Japan) having asymmetric structures. A SPM was used using the dynamic force microscopy (DFM), cyclic contact mode. The deep and tortuous pore structure on the inner surface of the hemoconcentrator membrane was observed for the first time using DFM. The pores had an elliptical shape, elongated in the longitudinal direction. When the elliptical area on the inner surface of the hemoconcentrator membrane was larger, pure water permeability was higher, showing a correlation between the elliptical area and membrane functions. The mean major pore diameters and minor pore diameters as well as the equivalent pore diameter calculated from the tortuous capillary pore model were consistent. Using DFM, the three-dimensional tortuous capillary pores at the inner surface of a hollow fiber hemoconcentrator membrane could be studied, and pore diameter and distribution could be measured by image analysis. The results were supported by the tortuous capillary pore model. In the future, we need to clearly show the further superior innovations or creative/ ingenious techniques related to this study. Further the state of new findings which contribute to development of a new hemoconcentrator and other semipermeable membranes will help to increase the value of this paper. This study is one of the key studies to achieve the targeted function for the transport phenomena through semipermeable membranes including hemoconcentrator.
  • ass transfer coefficient during hollow fiber dialysis membrane in a dialyzer by using dimensionless correlation equation based on the double film layer mass transfer model; compared with the single hollow fiber dialyzer, FUKUDA MAKOTO, 13 - 20, Sep. 2018 , Refereed
  • Identical dependence of dialysate-side mass transfer coefficient on Reynolds number using dimensionless correlation based on the mass transfer model in newly developed dialyzers and a downsized dialyzer., FUKUDA MAKOTO, Advanced Biomedical Engineering, Advanced Biomedical Engineering, 5, 118 - 123, Jun. 2016 , Refereed
  • 脱血部におけるローラポンプ圧力変動がバックフロー(BF)に及ぼす影響とBFによる脱血状態監視の有用性, 福田誠, 山本和輝, 前田圭介, 酒井清孝, 医工学治療, 医工学治療, 27(1), 21 - 28, Mar. 2015 , Refereed
  • Mass Transfer in a Dialyzer, FUKUDA Makoto, 膜, 膜, 37(1), 10 - 16, Jan. 2012 , Refereed
  • Effects of fluid flow on elution of hydrophilic modifier from dialysis membrane surface, MATSUDA Masato, SATO Mika, SAKATA Hiroki, OGAWA Takahisa, YAMAMOTO Ken-ichiro, YAKUSHIJI Taiji, FUKUDA Makoto, MIYASAKA Takehiro, SAKAI Kiyotaka, 人工臓器, 人工臓器, 39(1), 31 - 32, Jun. 15 2010 , Refereed
  • Different levels of hepatitis C virus adsorption by dialysis membranes during hemodialysis therapy, KOTERA Hirohisa, OHASHI Atsushi, NAKAI Shigeru, FUKUDA Makoto, ONISHI Shigeki, YASHIRO Masatomo, NABESHIMA Kunihiro, MURAKAMI Kazutaka, TOMITA Makoto, HASEGAWA Midori, HIKI Yoshiyuki, SUGIYAMA Satoshi, Nihon Toseki Igakkai Zasshi, Nihon Toseki Igakkai Zasshi, 43(1), 55 - 60, Jan. 2010 , Refereed
    Summary:The concentrations of hepatitis C virus (HCV) are reported to be lower in dialysis patients than in HCV-positive non-dialysis patients. We investigated the elimination dynamics of HCV antigens (core proteins) levels pre- and post-dialysis using a regenerated cellulose membrane (CU ; AM-FP1.3), cellulose triacetate membrane (CTA ; FB-150E), polymethylmethacrylate membrane (PMMA ; BK-1.6P), or polysulfone membrane (PS ; F-70S). The rates of HCV antigen decrease by a single dialysis session were as follows 32.7&plusmn;10.5% with the F-70S, 19.0&plusmn;2.2% with the BK-1.6P, 10.4&plusmn;1.7% with the FB-150E, and 8.8&plusmn;2.2% with the AM-FP1.3. Furthermore, we compared the HCV antigen elimination ability of each dialysis membrane material in an <I>in vitro</I> experiment. We perfused albumin (Alb) containing HCV in the blood circuit connected to AM-FP1.3, FB-130U, BK-1.3P, and F-60S, and measured quantities of HCV antigen and Alb over time. The quantity of HCV antigen decreased 25.8% with the F-60S, 20.5% with the BK-1.3P, 16.0% with the FB-130U, and 10.5% with the AM-FP1.3. Furthermore, to confirm HCV adsorption to the dialysis membrane, we perfused washing solution containing non-ionic surfactant in the blood circuit used in the above investigation, and measured quantities of HCV antigen in the washing solution. The quantities of HCV antigen eluted in the washing solution were nearly equivalent to the decreases in HCV observed in the <I>in vitro</I> experiment. In conclusion, HCV in blood is adsorbed and eliminated by dialysis membranes.
  • Anisotropie differences in solute transfer rate through asymmetric membrane 〈biorexreg; am-bc-x〉, M. Fukuda, Japanese Journal of Artificial Organs, Japanese Journal of Artificial Organs, 29, 411 - 418, Dec. 2000 , Refereed
    Summary:〈BIOREX AM-BC-X〉 is a new cellulosic membrane whose pore size is distributed asymmetrically in the membrane wall. The objectives of the present study are to clarify the phenomenon of solute transfer occurring inside dialyzers made from asymmetric membranes, to examine the structure of the asymmetric membrane capable of suppressing the inflow of endotoxins from dialysate, and thereby to contribute to the design of a more effective dialysis membrane. Using membranes that have tight layers on both sides (drum-shaped membrane, 〈BIOREX AM-BC-X〉 with the outer one tighter, solutes are more easily transferred from the inside out than from the outside in, leading to effective removal of pathogenic substances from blood and a significant lowering of endotoxin inflow from the dialysate. In asymmetric dialysis membranes, the anisotropy of solute permeability is caused by the difference in the amount of solute transfer due to filtration from the inside out and from the outside in.
  • Newly Developed Biocompatible Membrane ((BIOREX AM-BC-F)) and Effects of Its Smoother Surface on Anti-thrombogenesis., FUKUDA MAKOTO, MIYAZAKI MAKOTO, HIYOSHI TATSUO, 人工臓器(日本人工臓器学会), 人工臓器(日本人工臓器学会), 28(2), 458 - 464, Apr. 1999 , Refereed
  • Characterization of the cuprammonium cellulose membrane((BIOREX AM-BC-X)) with a symmetrical gradient pore structure., OGAWA HAJIME, MATSUYAMA IEHISA, FUKUDA MAKOTO, MIYAZAKI MAKOTO, HIYOSHI TATSUO, NISHIDA OSAMU, 人工臓器(日本人工臓器学会), 人工臓器(日本人工臓器学会), 28(1), 138 - 144, Feb. 1999 , Refereed
  • Characterization of the cuprammonium cellulose membrane <BIOREX AM-BC- X> with a symmetrical gradient pore structure, H. Ogawa, I. Matsuyama, M. Fukuda, M. Miyazaki, T. Hiyoshi, O. Nishida, Japanese Journal of Artificial Organs, Japanese Journal of Artificial Organs, 28, 138 - 144, Jan. 1999 , Refereed
    Summary:<BIOREX AM-BC-X> is a new cellulosic membrane with a symmetrical gradient morphology in pore size distribution in the membrane wall. The pore radius surrounding the middle part of the membrane wall is larger than that of the <BIOREX AM-BC-F>. The inner surface is as smooth as that of the <AM- BC-F>. <BIOREX AM-BC-X> has some advantages required for hemodialysis membranes, (1) reduced mass transfer resistance, (2) reduced backfiltration of pyrogens from dialysate side into blood side, (3) reduced albumin penetration and adhesion onto membrane wall, (4) adequate mechanical strength, compared with symmetrical, gradient, reversed gradient pore structure membranes, respectively. These characteristic advantages are brought about by the symmetrical gradient pore structure.
  • Newly developed biocompatible membrane (BIOREX AM-BC-F) and effects of its smoother surface on anti-thrombogenesis, M. Fukuda, M. Miyazaki, T. Hiyoshi, Japanese Journal of Artificial Organs, Japanese Journal of Artificial Organs, 28, 458 - 464, Jan. 1999 , Refereed
    Summary:A new biocompatible cellulosic membrane (BIOREX AM-BC-F) has been developed, which has a higher flux than conventional membranes and more excellent anti-thrombogenicity. These improvements are due to the membrane's smoother surface. The inner surface of the (AM-BC-F) membrane was less rough than that of conventional membranes, an observation conducted by Atomic Force Microscopy. The membrane was produced by the newly developed cuprammonium cellulose solution spinning, which has a different composition from that of a conventional cuprammonium cellulose solution. The degree of platelet adhesion (number of platelet adhered) on the membrane surface was evaluated in vitro. The number of platelet that adhered to the <AM-BC-F> was far smaller than that of conventional membranes. It was thought that these results were due to the membrane's smoother surface.
  • Surface Roughness of Cellulose Hollow Fiber Dialysis Membrane and Its Effects on Antithrombogenicity., TSUNODA NANAE, KOKUBO KEN'ICHI, SAKAI KIYOTAKA, FUKUDA MAKOTO, MIYAZAKI MAKOTO, HIYOSHI TATSUO, 人工臓器(日本人工臓器学会), 人工臓器(日本人工臓器学会), 27(2), 475 - 479, Apr. 1998 , Refereed
  • Characteristics of the alkyl ether chain grafted cellulosic membrane ((BIOREX AM-BC-F))., FUKUDA MAKOTO, MIYAZAKI MAKOTO, HIYOSHI TATSUO, HONGO TOMOKO, UESAKA MASATOSHI, MAEKAWA TOMOTERU, YABUSHITA HAJIME, MATSUYAMA IEHISA, OGAWA HAJIME, 人工臓器(日本人工臓器学会), 人工臓器(日本人工臓器学会), 27(1), 212 - 216, Feb. 1998 , Refereed
  • Characteristics of the alkyle ether chain grafted cellulosic membrane <<Biorex AM-BC-F>>, M. Fukuda, M. Miyazaki, T. Hiyoshi, Japanese Journal of Artificial Organs, Japanese Journal of Artificial Organs, 27, 212 - 216, Jan. 1998 , Refereed
    Summary:<<BIOREX AM-BC-F>> is the new cellulosic membrane of which the inner surface is smoother than that of conventional cellulosic membrane, and alkyl ether carboxylic acid(polyethylene glycol) chain is grafted onto the inner surface of the membrane. <<AM-BC-F>> is produced by the new spinning method <<FIS(Fine Inner Surface) Technology>>. It can be expected that it reduces hydrodynamic resistance between blood and the membrane. And it reduces complement activation in vivo, because rapid movement of the flexible PEG chain, <<Diffusive Layer>>, leads to less interaction between blood and membrane.
  • Surface roughness of cellulose hollow fiber dialysis membrane and its effects on antithrombogenicity, N. Tsunoda, K. Kokubo, K. Sakai, M. Fukuda, T. Hiyoshi, Japanese Journal of Artificial Organs, Japanese Journal of Artificial Organs, 27, 475 - 479, Jan. 1998 , Refereed
    Summary:Biocompatibility of dialysis membrane has been studied directing our attention to difference in membrane material. To clarify a membrane of bus formation, it should be evaluated with respect to not only membrane material but also flow characteristics on membrane surface depending on surface roughness. Platelet adhesion on the membrane surface was measured using 5 dialysis membranes of different surface roughneses. Bovine blood (500 ml) added with trisodium citrate dihydrate (approximately 2 g) as an anticoagulant was circulated in a test dialyzer at a flow rate of 200 ml/min. Pressure drop and flow rate of PMMA (particle diameter : 1 μm) suspension in glycerol (Bingham fluid) (glycerol : PMMA = 2: 1 by weight ratio) were measured to determine yield stress. The yield stress of the membranes and increased with surface roughness. The amount of platelet adhesion increased with yield stress, indicating that the platelet adhesion depends on surface roughness.
  • Differences in Mass Transfer Through Asymmetrical Dialysis Membrane with Different Rejections between Transport Directions., ONISHI TSUYOSHI, KOKUBO KEN'ICHI, SAKAI KIYOTAKA, FUKUDA MAKOTO, HIYOSHI TATSUO, 人工臓器(日本人工臓器学会), 人工臓器(日本人工臓器学会), 26(3), 734 - 738, Jun. 1997 , Refereed
  • Characterization of the symmetrical gradient pore structure of the cuprammonium cellulose membrane ((PT-X))., MIYAZAKI MAKOTO, FUKUDA MAKOTO, HIYOSHI TATSUO, 人工臓器(日本人工臓器学会), 人工臓器(日本人工臓器学会), 26(1), 165 - 170, Feb. 1997 , Refereed
  • Characterization of the symmetrical gradient pore structure of the cuprammonium cellulose membrane <<PT-X>>, M. Miyazaki, M. Fukuda, T. Hiyoshi, Japanese Journal of Artificial Organs, Japanese Journal of Artificial Organs, 26, 165 - 170, Jan. 1997 , Refereed
    Summary:It is well known that performances of hemodialysis membrane depend on its pore structure. Herein the new pore structure membrane <PT-X> is proposed <PT-X> has a symmetrical gradient morphology in pore size distribution in the membrane wall. The pore radius around middle part of the membrane wall is larger than that of surface parts <PT-X> has some advantages requied for hemodialysis membranes, (1) reduced mass transfer resistance, (2) reduced backfiltration of pyrogens from dialysate side into blood side, (3) reduced albumin penetration and adhesion onto membrane wall, (4) adequate mechanical strength, compared with symmetrical, gradient, reversed gradient and symmetrical pore structure membranes, respectively. These characteristic advantages are brought about for the symmetrical gradient pore structure.
  • Water content in wet dialysis membranes of various polymers and its effects on intramembrane diffusivity., KANAMORI T, SAKAI K, Jinko Zoki, Jinko Zoki, 23(3), 578 - 584, 1994 , Refereed
    Summary:Intramembrane diffusivity and water permeability are essential for characterization of dialysis membranes. The physical state of water present in the membrane may affect the solute diffusivity because solutes diffuse into only a fraction of water in the membrane and water inside the membrane changes places with that outside the membrane. Water content was measured in 31 dialysis membranes made of 7 polymers. The physical state of water was determined from data on water content by the conventional method and the differential scanning calorimetry and on partition coefficient measured by the use of tritium-labeled water. Three kinds of water state of varying molecular mobilities were found in the membranes and their volume ratio was dependent on the membrane material. The mechanism of solute transport through hydrophilic dialysis membranes of regenerated cellulose that strongly put restrictions on the movement of water in the membrane was different from that through hydrophobic dialysis membranes. Analysis of the intramembrane diffusivity of the regenerated cellulose membrane based on the free volume theory revealed that the solute diffusivity was dependent on water content.
  • Effects of grafting polyethylene glycol(PEG) on membrane structure and solute permeability of PEG-grafted regenerated cellulose membranes., FUKUDA M, KANAMORI T, SAKAI K, Jinko Zoki, Jinko Zoki, 22(1), 47 - 52, 1993 , Refereed
    Summary:Complement activation is reduced by grafting polyethylene glycol (PEG) on the surface of conventional regenerated cellulose (RC) membranes. However, the solute permeability of PEG-grafted RC membranes may be lower than that of conventional RC membranes because of the presence of swollen-layers formed with PEG chains on the PEG-grafted RC membranes. The objective of the present study is to clarify the difference in membrane structure between conventional RC (AM-SD) and PEG-grafted RC (AM-PC) membranes, and to characterize three PEG-grafted cellulosic membranes (AM-PC(l), PC(m), PC(s)) with varying PEG chain lengths based on the tortuous capillary pore model using data on tritium-labeled water (HTO) permeability and filtration coefficient.<br>The pore radius and surface porosity of the AM-SD, PC (m) and PC (s) membranes were calculated to be 2.8nm and 35%, respectively. On the other hand, the pore radius and surface porosity of the PC(l) membrane grafted with the longest PEG chains were lower than those of the conventional RC membrane (SD). This indicates that the pores of the PC (l) membrane are partially covered with the PEG chains.
  • The structure of hollow-fiber dialysis membranes by solute permeability determined through different methods., FUKUDA MAKOTO, AWAKA TOORU, KANAMORI TOSHIYUKI, SAKAI KIYOTAKA, 人工臓器(日本人工臓器学会), 人工臓器(日本人工臓器学会), 21(3), 861 - 866, Jun. 1992 , Refereed
  • Optical Determination of Solute Permeability of Highly Permeable Dialysis Membranes., Kanamori Toshiyuki, Fukuda Makoto, Sakai Kiyotaka, MEMBRANE, MEMBRANE, 17(1), 19 - 26, 1992 , Refereed
    Summary:A few highly permeable dialysis membranes have been developed so far to remove beta-2-microglobulin having a molecular weight of 11, 800 that was identified as a new form of amyloid protein from patients on long-term hemodialysis. The present study is to evaluate the solute permeability for low molecular weight proteins such as beta-2-microglobulin of the highly permeable dialysis membranes by varying technical methods.<BR>The membranes tested included conventional and highly permeable dialysis membranes made of regenerated cellulose, and also highly permeable dialysis membranes of polysulfone and polyacrylonitrile as a reference. Solute permeability was determined by 1) the Wilson-plot method, 2) the microanalysis method with radioisotope-labeled solutes and 3) the photometric measurement. Test solutes were vitamin B<SUB>12</SUB> beta-2-microglobulin, cytochrome-C and myoglobin.<BR>The highly permeable dialysis membranes of regenerated cellulose had higher surface porosities and pore sizes calculated from solute and pure water permeabilities and water content data that were practically the same as synthetic polymer membranes. This demonstrates that advanced membrane preparation techniques are capable of forming great surface porosity and large pore size on regenerated cellulose dialysis membranes.<BR>The Wilson-plot method is incapable of determination of diffusive permeability without ultrafiltration. Continuous measurements of optical density of a test solution in a hollow with optical fibers are well suited for precise determination of solute permeability by diffusion.<BR>The removed amount of beta-2-microglobulin calculated from solute permeability data of the most highly permeable dialysis membranes may not exceed the generated amount of beta-2-microglobulin.
  • Optimal design of dialyzers considering blood-side film resistance., AOKI Y, AWAKA T, FUKUDA M, KANAMORI T, SAKAI K, NISHIKIDO J, WATANABE T, FUSHIMI F, Jinko Zoki, Jinko Zoki, 21(3), 982 - 986, 1992 , Refereed
    Summary:Highly permeable (HP) membranes have higher solute permeabilities than conventional ones. Contribution of blood- and dialysate-side mass transfer resistances to solute removal performance is more increased in HP dialyzers than conventional ones. To reduce blood- and dialysate-side mass transfer resistances effectively increases solute removal performance especially of HP dialyzers. This paper describes the technical design of dialyzers with being reduced blood-side mass transfer resistance. Dialyzers consisting of hollow-fiber membranes of 19.4cm in length was superior in solute removal perormance to dialyzers consisting of hollow-fiber membranes of 23.5cm in length. Overall mass transfer coefficient and blood-side mass transfer coefficient were independent of blood-side flow rate. Overall mass transfer coefficient was independent of inner diameter of hollow fibers.
  • The structure of hollow-fiber dialysis membranes by solute permeability determined through different methods., FUKUDA M, AWAKA T, KANAMORI T, SAKAI K, Jinko Zoki, Jinko Zoki, 21(3), 861 - 866, 1992 , Refereed
    Summary:Solute permeability is available using Wilson-Plot Method, Klein's Method, RI Method with radioisotope-labeled solute and a new method with optical fibers. Each method gives different values for solute permeability of same membranes, and little is known real values for solute permeability. This paper describes characteristics of methods of measuring solute permeability, and effects of membrane structure on solute permeability of highly permeable (HP) dialysis membranes.<br>Real values for solute permeability of hollow-fiber dialysis membranes can be measured by a new method with optical fibers. Structural parameters of pore radius, surface porosity and tortuosity were determined for HP membranes from pure water permeability, solute permeability and water content data using the tortuous pore model. PAN-DX membrane has higher solute permeability than AM-EP membrane for substances of molecular weight ranging from 6, 000 to 20, 000, because PAN-DX membrane has huge pores.
  • The study on mass transfer in hollow fiber membrane by the new method with optical fibers., AWAKA T, FUKUDA M, AOKI Y, NAITO A, KANAMORI T, SAKAI K, Jinko Zoki, Jinko Zoki, 21(3), 873 - 876, 1992 , Refereed
    Summary:Relationship between mass transfer and flow patttern in dialyzers is very important for optimal design of dialyzers. Mass transfer in dialysate-side is extremely complex to understand due to complexity of flow pattern. In this work, the basic analysis about mass transfer of dialysate was performed with single follow fiber membrane, which is considered as a simplest laminar flow condition. The experiment was carried out by the new method with optical fibers. The unsteady mass transfer model in a capillary membrane was applied to the new calculation method for the mass transfer coefficient of outside film of the hollow fiber membrane. AM-SD-10M which is conventional membrane and AM-FP-15 which is highly permeaole membrane were used in the experiment. No matter which membrane was concerned, mass transfer resistances of outside film were equal. Sherwood number measured experimentally fitted in with the Leveque's equation which was led by the theoretical analysis of heat transfer in laminar flow.
  • Effects of grafting polyethylene glycol(PEG) on membrane structure and solute permeability of PEG-grafted regenerated cellulose membranes., FUKUDA MAKOTO, KANAMORI TOSHIYUKI, SAKAI KIYOTAKA, 人工臓器(日本人工臓器学会), 人工臓器(日本人工臓器学会), 22(1), 47 - 52, 1992 , Refereed
  • Optimal design of dialyzers considering dialysate film resistances., FUKUDA M, HOSOYA N, KANAMORI T, SAKAI K, NISHIKIDO J, WATANABE T, FUSHIMI F, Jinko Zoki, Jinko Zoki, 20(1), 59 - 64, 1991 , Refereed
    Summary:Highly permeable (HP) membranes have higher solute permeabilities than conventional ones. As a result, the contribution of dialysate film mass transfer resistance increased on HP dialyzers. It should be reduced to improve the mass transfer performance of HP dialyzers. Little is known concerning the technical design of dialyzers, considering dialysate film mass transfer resistance. This paper describes the technical design of dialyzers to reduce the dialysate film mass transfer resistance. The dialysate film mass transfer coefficient increased with the fiber density. The increase in fiber density increased the mass transfer rate of HP dialyzers more effectively than that of conventional dialyzers. Keller's equation, commonly used for the technical design of dialyzers, should be modified because the dialysate film mass transfer coefficient calculated from the equation did not agree with those determined by a dialysis experiment.
  • Technical characterization of dialysis fluid flow and mass transfer rate in dialyzers with various filtration coefficients using dimensionless correlation equation, Makoto Fukuda, Kengo Yoshimura, Koki Namekawa, Kiyotaka Sakai, JOURNAL OF ARTIFICIAL ORGANS, JOURNAL OF ARTIFICIAL ORGANS, 20(2), 145 - 151, Jun. 2017 , Refereed
    Summary:The objective of the present study is to evaluate the effect of filtration coefficient and internal filtration on dialysis fluid flow and mass transfer coefficient in dialyzers using dimensionless mass transfer correlation equations. Aqueous solution of vitamin B-12 clearances were obtained for REXEED-15L as a low flux dialyzer, and APS-15EA and APS-15UA as high flux dialyzers. All the other design specifications were identical for these dialyzers except for filtration coefficient. The overall mass transfer coefficient was calculated, moreover, the exponents of Reynolds number (Re) and film mass transfer coefficient of the dialysis-side fluid (k(D)) for each flow rate were derived from the Wilson plot and dimensionless correlation equation. The exponents of Re were 0.4 for the low flux dialyzer whereas 0.5 for the high flux dialyzers. Dialysis fluid of the low flux dialyzer was close to laminar flow because of its low filtration coefficient. On the other hand, dialysis fluid of the high flux dialyzers was assumed to be orthogonal flow. Higher filtration coefficient was associated with higher k(D) influenced by mass transfer rate through diffusion and internal filtration. Higher filtration coefficient of dialyzers and internal filtration affect orthogonal flow of dialysis fluid.
  • Poly(N-vinyl-2-pyrrolidone) elution from polysulfone dialysis membranes by varying solvent and wall shear stress, Koki Namekawa, Masato Matsuda, Makoto Fukuda, Ami Kaneko, Kiyotaka Sakai, JOURNAL OF ARTIFICIAL ORGANS, JOURNAL OF ARTIFICIAL ORGANS, 15(2), 185 - 192, Jun. 2012 , Refereed
    Summary:Some dialysis patients are treated with post-hemodiafiltration (HDF); the blood viscosity of the patients who undergo post-HDF is higher than that of the patients who undergo conventional hemodialysis. This study aims to evaluate poly(N-vinyl-2-pyrrolidone) (PVP) elution from PSf dialysis membranes by varying solvents and high wall shear stress caused by blood viscosity. We tested three commercial membranes: APS-15SA (Asahi Kasei Kuraray), CX-1.6U (Toray) and FX140 (Fresenius). Dialysate and blood sides of the dialyzers were primed with reverse osmosis (RO) water and saline. RO water, saline and dextran solution (2.9 and 5.8 mPa s) were circulated in the blood side. The amount of eluted PVP was determined by 0.02 N iodometry. The hardness and adsorption force of human serum albumin (HSA) on the membrane surfaces were measured by the atomic force microscope. When wall shear stress was increased using dextran, the amount of PVP eluted by the 2.9 mPa s solution equaled that eluted by the 5.8 mPa s solution with APS-15SA and CX-1.6U sterilized by gamma rays. The amount of PVP eluted by the 5.8 mPa s solution was higher than that eluted by the 2.9 mPa s solution with FX140 sterilized by autoclaving. The wall shear stress increased the PVP elution from the surface, hardness and adsorption force of HSA. Sufficient gamma-ray irradiation is effective in decreasing PVP elution.
  • Development of a device for chemiluminescence determination of superoxide generated inside a dialysis hollow-fiber membrane, Takehito Ogawa, Sumire Koga, Taiji Yakushiji, Masato Matsuda, Ken-ichiro Yamamoto, Hiroki Sakata, Makoto Fukuda, Takehiro Miyasaka, Kiyotaka Sakai, JOURNAL OF ARTIFICIAL ORGANS, JOURNAL OF ARTIFICIAL ORGANS, 13(1), 58 - 62, Apr. 2010 , Refereed
    Summary:Reactive oxygen species (ROS) generated during hemodialysis treatment cause dialysis complications because of the high reactivity of ROS. To prevent dialysis complications caused by oxidative stress, it is important to evaluate the generation and dismutation of ROS during hemodialysis treatment. In this study, our aim was to develop a device to determine superoxide (O(2) (-)) generated inside a dialysis hollow fiber, and also to examine whether this device could detect O(2) (-) separated from plasma using hollow fibers. Experimental apparatus was set up so that hypoxanthine (HX) solution flowed inside the hollow fibers and 2-methyl-6-p-methoxyphenylethynyl-imidazopyrazinone (MPEC) solution flowed outside the hollow fibers. Then, xanthine oxidase (XOD) solution was added to the HX solution to generate O(2) (-), and chemiluminescence resulting from the reaction of O(2) (-) with MPEC was measured with an optical fiber. Chemiluminescence intensity was measured at different HX concentrations, and the peak area of relative luminescence intensity yielded a first-order correlation with the HX concentration. Based on the relationship between HX and O(2) (-) concentrations determined by the cytochrome c reduction method, the relative luminescence intensity measured by this device was linearly dependent on the O(2) (-) concentration inside the hollow fibers. After modifications were made to the device, XOD solution injection into plasma including HX resulted in an increase in the relative luminescence intensity. We concluded that this novel device based on chemiluminescence is capable of determining aqueous O(2) (-) generated inside a hollow fiber and also of detecting O(2) (-) in plasma.
  • Computational Evaluation of Dialysis Fluid Flow in Dialyzers With Variously Designed Jackets, Ken-ichiro Yamamoto, Masato Matsuda, Ayaka Hirano, Natsuo Takizawa, Shigeto Iwashima, Taiji Yakushiji, Makoto Fukuda, Takehiro Miyasaka, Kiyotaka Sakai, ARTIFICIAL ORGANS, ARTIFICIAL ORGANS, 33(6), 481 - 486, Jun. 2009 , Refereed
    Summary:Dialyzer performance strongly depends on the flow of blood and dialysis fluid as well as membrane performance. It is necessary, particularly to optimize dialysis fluid flow, to develop a highly efficient dialyzer. The objective of the present study is to evaluate by computational analysis the effects of dialyzer jacket baffle structure, taper angle, and taper length on dialysis fluid flow. We modeled 10 dialyzers of varying baffle angles (0, 30, 120, 240, and 360 degrees) with and without tapers. We also modeled 30 dialyzers of varying taper lengths (0, 12.5, 25.0, and 50.0 mm) and angles (0, 2, 4, and 6 degrees) based on technical data of APS-SA dialyzers having varying surface areas of 0.8, 1.5, and 2.5 m(2) (Rexeed). Dialysis fluid flow velocity was calculated by the finite element method. The taper part was divided into 10 sections of varying fluid resistances. A pressure of 0 Pa was set at the dialysis fluid outlet, and a dialysis fluid flow rate of 500 mL/min at the dialysis fluid inlet. Water was used as the dialysis fluid in the computational analysis. Results for dialysis fluid flow velocity of the modeled dialyzers indicate that taper design and a fully surrounded baffle are important in making the dialysis fluid flow into a hollow-fiber bundle easily and uniformly. However, dialysis fluid flow channeling occurred particularly at the outflowing part with dialyzers having larger taper lengths and angles. Optimum design of dialysis jacket structure is essential to optimizing dialysis fluid flow and to increasing dialyzer performance.
  • Technical Characterization of Dialysis Fluid Flow of Newly Developed Dialyzers Using Mass Transfer Correlation Equations, Satoru Kunikata, Makoto Fukuda, Ken-Ichiro Yamamoto, Yutaka Yagi, Masato Matsuda, Kiyotaka Sakai, ASAIO JOURNAL, ASAIO JOURNAL, 55(3), 231 - 235, May 2009 , Refereed
    Summary:Dialysis fluid flow and mass transfer rate of newly developed dialyzers were evaluated using mass transfer correlation equations of dialysis fluid-side film coefficient. Aqueous creatinine clearance and overall mass transfer coefficient for APS-15S (Asahi Kasei Kuraray) as a conventional dialyzer, and APS-15SA (Asahi Kasei Kuraray), PES-150S alpha (Nipro), FPX140 (Fresenius), and CS-1.61U (Toray) as newly developed dialyzers were obtained at a blood-side flow rate (Q,) of 200 ml/min, dialysis fluid-side flow rates (Q(D)) of 200-800 ml/min and a net filtration rate (Q,) of 0 ml/min. Mass transfer correlation equations between Sherwood number (Sh) containing dialysis fluid-side mass transfer film coefficient and Reynolds number (Re) were formed for each dialyzer. The exponents of Re were 0.62 for APS-15S whereas approximately 0.5 for the newly developed dialyzers. The dialysis fluid-side mass transfer film coefficients of the newly developed dialyzers were higher than those of the conventional dialyzer. Based on the mass transfer correlation equations, introduction of short taper, full baffle of dialyzer jacket and further wave-shaped hollow fiber improves the dialysis fluid flow of the newly developed dialyzers. ASAIO journal 2009; 55:231-235.
  • Nanotechnological Characterization of Human Serum Albumin Adsorption on Wet Synthetic Polymer Dialysis Membrane Surfaces, Koki Namekawa, Makoto Fukuda, Masato Matsuda, Yutaka Yagi, Ken-Ichiro Yamamoto, Kiyotaka Sakai, ASAIO JOURNAL, ASAIO JOURNAL, 55(3), 236 - 242, May 2009 , Refereed
    Summary:The objective of the present study was to evaluate the characteristics of protein adsorption on the inner surface of various dialysis membranes, to develop protein adsorption-resistant biocompatible dialysis membranes. The adsorption force of human serum albumin (HSA) on the inner surface of a dialysis membrane and the smoothness of the membrane were evaluated from a nanoscale perspective by atomic force microscopy. The content ratio of the hydrophilic polymer, polyvinylpyrrolidone (PVP), was determined by attenuated total reflection Fourier transform infrared spectroscopy. Nine synthetic-polymer dialysis membranes on the market made of polysulfone (PSF), polyethersulfone (PES), polyester polymer-alloy (PEPA), and ethylene vinylalcohol (EVAL) were used in the present study. The HSA adsorption force on the surface of the hydrophobic polymer PEPA membrane was higher than that on the hydrophilic polymer EVAL membrane surface. It has been considered beneficial, for decreasing the HSA adsorption force, to cover a hydrophobic polymer membrane surface with PVP. However, there were some areas on PVP-containing membrane surfaces at which much higher HSA adsorption forces were observed. The HSA adsorption force gave a nearly linear correlation with the surface roughness on the PSF membrane surface. However, the HSA adsorption force was uncorrelated with the PVP content ratio for any of the PSF membrane surfaces tested. in conclusion, protein adsorption can be minimized by the use of dialysis membranes made of hydrophobic polymers containing PVP with a smooth surface. ASAIO journal 2009; 55:236-242.
  • Effects of fluid flow on elution of hydrophilic modifier from dialysis membrane surfaces, Masato Matsuda, Mika Sato, Hiroki Sakata, Takahisa Ogawa, Ken-ichiro Yamamoto, Taiji Yakushiji, Makoto Fukuda, Takehiro Miyasaka, Kiyotaka Sakai, JOURNAL OF ARTIFICIAL ORGANS, JOURNAL OF ARTIFICIAL ORGANS, 11(3), 148 - 155, Sep. 2008 , Refereed
    Summary:When uremic blood flows through dialyzers during hemodialysis, dialysis membrane surfaces are exposed to shear stress and internal filtration, which may affect the surface characteristics of the dialysis membranes. In the present study, we evaluated changes in the characteristics of membrane surfaces caused by shear stress and internal filtration using blood substitutes: water purified by reverse osmosis and 6.7 wt% dextran70 solution. We focused on the levels of a hydrophilic modifier, polyvinylpyrrolidone (PVP), on the membrane surface measured by attenuated total reflectance Fourier transform infrared spectroscopy. Experiments involving 4 h dialysis, 0-144 h shear-stress loading, and 4 h dead-end filtration were performed using polyester-polymer alloy (PEPA) and polysulfone (PS) membranes. After the dialysis experiments with accompanying internal filtration, average PVP retention on the PEPA membrane surface was 93.7% in all areas, whereas that on the PS membrane surface was 98.9% in all areas. After the shear-stress loading experiments, PVP retention on the PEPA membrane surface decreased as shear-stress loading time and the magnitude of shear stress increased. However, with the PS membrane, PVP retention scarcely changed. After the dead-end filtration experiments, PVP retention decreased in all areas for both PEPA and PS membranes, but PVP retention on the PEPA membrane surface was lower than that on the PS membrane surface. PVP on the PEPA membrane surface was eluted by both shear stress and internal filtration, while that on the PS membrane surface was eluted only by internal filtration.
  • Nanotechnological evaluation of protein adsorption on dialysis membrane surface hydrophilized with polyvinylpyrrolidone, Masato Matsuda, Ken-ichiro Yamamoto, Taiji Yakushiji, Makoto Fukuda, Takehiro Miyasaka, Kiyotaka Sakai, JOURNAL OF MEMBRANE SCIENCE, JOURNAL OF MEMBRANE SCIENCE, 310(1-2), 219 - 228, Mar. 2008 , Refereed
    Summary:Hydrophilizing synthetic polymer dialysis membranes with polyvinylpyrrolidone (PVP) play an important role for inhibition of protein adsorption on membrane surface. In the present study, the effect of PVP on protein adsorption was evaluated from a nano-scale perspective. Swelling behavior of PVP present on wet polysulfone (PS)/PVP film surfaces was observed by atomic force microscopy (AFM). Fibrinogen and human serum albumin (HSA) were immobilized on the tip of AFM probes, with which a force-curve between protein and wet PS/PVP film surface was measured by AFM while scanning in order to visualize two-dimensional protein adsorbability on film surfaces. Furthermore, HSA adsorbability on non-PVP containing PEPA dialysis membrane (FLX-15GW) and PVP containing PEPA dialysis membrane (FDX-150GW) was evaluated by the AFM force-curve method. As a result, PS/PVP film surface was completely covered with hydrated and swollen PVP at 5 wt% or more PVP content. Protein adsorbability on PS/PVP film surfaces decreased greatly with increasing content of PVP. The adsorption of HSA was inhibited by the presence of PVP on film surfaces more significantly than that of more hydrophobic fibrinogen. HSA adsorbability on wet FLX-15GW dialysis membrane surface was 428+/-174 pN whereas that on wet FDX-150GW dialysis membrane surface was 42+/-29 pN. (C) 2007 Elsevier B.V. All rights reserved.
  • Antioxidation property of vitamin E-coated polysulfone dialysis membrane an recovery of oxidize vitamin E by vitamin C treatment, Ken-Ichiro Yamamoto, Masato Matsuda, Masashi Okuoka, Taiji Yakushiji, Makoto Fukudab, Takehiro Miyasaka, Yutaka Matsumoto, Kiyotaka Sakai, JOURNAL OF MEMBRANE SCIENCE, JOURNAL OF MEMBRANE SCIENCE, 302(1-2), 115 - 118, Sep. 2007 , Refereed
    Summary:The antioxidation property of vitamin E-coated dialysis membrane is effective for reduction of oxidative stress. Effect of amount of vitamin E coating on antioxidation property has been poorly understood yet. In the present study, we evaluated a relationship between amount of vitamin E coating and antioxidation property using a superoxide probe of 2-methyl-6-p-methoxyphenylethynylimidazopyrazinone (MPEC) by the optical fiber method to determine optimum amount of vitamin E coating and to improve antioxidation property of the vitamin E-coated dialysis membrane. Furthermore, from the viewpoint of reuse, we examined recovery of oxidized vitamin E by vitamin C treatment. In conclusion, it is necessary to coat polysulfone dialysis membranes with vitamin E at over 74 mg/m(2). The antioxidation property is recoverable by treating dialysis membrane containing oxidized vitamin E with vitamin C. By administrating vitamin C, higher antioxidation property may be realized with a small amount of vitamin E coating. (c) 2007 Elsevier B.V. All rights reserved.
  • Technical evaluation of dialysate flow in a newly designed dialyzer, Ken-Ichiro Yamamoto, Hiroaki Matsukawa, Taiji Yakushiji, Makoto Fukuda, Tatsuo Hiyoshi, Kiyotaka Sakai, ASAIO JOURNAL, ASAIO JOURNAL, 53(1), 36 - 40, Jan. 2007 , Refereed
    Summary:Rexeed was developed by Asahi Kasei Medical using wave-shaped hollow fibers, a full baffle, and a short taper housing to improve dialysate flow. The present study is clarifies improvement in dialysate flow with Rexeed-15 compared with that of a conventional dialyzer. Dialysate flow was evaluated by the pulse-response method. Dialysate pressure and tracer concentration were measured at a blood-side flow rate (Q(B)) of 200 ml/min, a dialysate-side flow rate (Q(D)) of 500 ml/min, and a net filtration rate (Q(F)) of 0 ml/min using needles placed in the test dialyzer. Dialyzer performance was evaluated by measuring urea and vitamin B-12 clearance at Q(B) = 200 and 400 ml/min, Q(D) = 300-800 ml/min, and Q(F) = 0 ml/min. In the conventional dialyzer, dialysate channeling was observed. In contrast, Rexeed-15 had a uniform dialysate flow. Urea and vitamin B-12 clearance with Rexeed-15 was slightly sensitive to Q(D). The overall mass transfer coefficient for urea with Rexeed-15 was more than 50% higher than that of the conventional dialyzer, indicating the possibility of reduced dialysate usage with Rexeed. Rexeed has a highly optimal dialysate flow, due to the wave-shaped hollow fibers and the new housing, and gives increased clearance for lower-molecular-weight substances.
  • Evaluation of asymmetrical structure dialysis membrane by tortuous capillary pore diffusion model, Ken-ichiro Yamamoto, Masayo Hayama, Masato Matsuda, Taiji Yakushiji, Makoto Fukuda, Takehiro Miyasaka, Kiyotaka Sakai, JOURNAL OF MEMBRANE SCIENCE, JOURNAL OF MEMBRANE SCIENCE, 287(1), 88 - 93, Jan. 2007 , Refereed
    Summary:The tortuous capillary pore diffusion model (TCPDM) has been used for estimating diffusive and pure water permeability from simple structure parameters such as pore diameter, surface porosity, wall thickness and tortuosity. The validity of this model for evaluation of homogeneous membrane has been already confirmed. Recently, there is a trend toward the use of asymmetrical dialysis membranes made of synthetic polymer such as poly(acrylonitrile) (PAN), polysulfone (PS) and a polyethersulfone polyarylate (PEPA) blend polymer. The purpose of the present study is to apply the TCPDM to evaluation of commercially available hollow-fiber dialysis membranes with asymmetrical structures by simplifying them to a double-layer membrane. The TCPDM is capable of estimating pore tortuosity of asymmetrical dialysis membranes having skin and supporting layers from data on membrane thickness, pore diameter, pure water permeability and water content. Values for diffusive permeability obtained by the TCPDM are in a good agreement with experimental data. This TCPDM model is useful for evaluation of not only homogeneous membrane but also asymmetrical membrane. (c) 2006 Elsevier B.V. All rights reserved.
  • Improved housing of a new dialyzer to optimize dialysate flow, Ken-ichiro Yamamoto, Shigeto Iwashima, Mai Hasegawa, Masato Matsuda, Kiyotaka Sakai, Taiji Yakushiji, Makoto Fukuda, Takehiro Miyasaka, NEPHROLOGY DIALYSIS TRANSPLANTATION, NEPHROLOGY DIALYSIS TRANSPLANTATION, 22, 122 - 123, 2007 , Refereed
  • Design and assessment of the new APS dialyzer (APS-SA series), Makoto Fukuda, Miwa Miyazaki, Satoshi Uezumi, Makoto Yoshida, Journal of Artificial Organs, Journal of Artificial Organs, 9(3), 192 - 198, Sep. 2006 , Refereed
    Summary:Dialyzer performance seems to greatly depend on the hollow-fiber membrane performance, the morphology of the hollow-fiber membrane bundles (e.g., wave-shaped hollow-fiber membrane bundles), and the design of the dialyzer housing. Consequently, we developed the APS dialyzer APS-SA series, equipped with wave-shaped hollow-fiber membrane bundles as an optimal three-dimensional morphology along with new housings, to realize enhanced dialysis performance. Incorporation of a new type of housing, including a full baffle structure and a short taper section, and a new type of morphology for the hollow-fiber membrane bundles have been verified to allow the dialysate to diffuse uniformly along the full baffle panel around the circumference and to fully permeate into the core of the hollow-fiber bundle. As a result, the APS-SA series has been proved to have achieved enhanced diffusion performance and increased clearance of small molecule solutes such as urea and creatinine, compared with conventional dialyzers. This series is expected to provide increased Kt/V values and dialysate-saving performance in future clinical use. © 2006 The Japanese Society for Artificial Organs.
  • Membrane fouling and dialysate flow pattern in an internal filtration-enhancing dialyzer, Ken-Ichiro Yamamoto, Michihito Hiwatari, Fukashi Kohori, Kiyotaka Sakai, Makoto Fukuda, Tatsuo Hiyoshi, Journal of Artificial Organs, Journal of Artificial Organs, 8(3), 198 - 205, Sep. 2005 , Refereed
    Summary:For efficient removal of large molecular weight solutes by dialysis, several types of internal filtration-enhancing dialyzers (IFEDs) are commercially available. However, in a pressure-driven membrane separation process (i.e., filtration), membrane fouling caused by adhesion of plasma proteins is a severe problem. The objective of the present study is to investigate the effects of internal filtration on membrane fouling based on the membrane's pure-water permeability, diffusive permeability, and sieving coefficient. Hemodialysis experiments were performed with two different dialyzers, IFEDs and non-IFEDs. Local membrane fouling in each dialyzer was evaluated by measuring the pure-water permeability, the diffusive permeability, and the sieving coefficient of native membranes and membranes treated with bovine blood. The effects of packing ratio on dialysate flow pattern were also evaluated by measuring the time required for an ion tracer to reach electrodes placed in the dialyzers. In the IFED, membrane fouling caused by protein adhesion is increased because of enhanced internal filtration only at the early stage of dialysis, and this fouling tends to occur only near the dialysate outlet port. However, enhanced internal filtration has little effect on measured membrane transfer parameters. © The Japanese Society for Artificial Organs 2005.
  • Development of a dialyzer with enhanced internal filtration to increase the clearance of low molecular weight proteins, Takayasu Fujimura, Yukihiko Uchi, Makoto Fukuda, Miwa Miyazaki, Satoshi Uezumi, Tatsuo Hiyoshi, Journal of Artificial Organs, Journal of Artificial Organs, 7(3), 149 - 154, Sep. 2004 , Refereed
    Summary:Accumulated low molecular weight proteins in hemodialysis patients require a high-flux dialyzer. There have been several methods proposed for enhancing internal filtration, including narrowing the inside diameter of the hollow fibers, lengthening the fibers, and increasing the fiber density ratio. We tried to enhance the internal filtration by increasing the pressure drop in the dialysate compartment through increasing the fiber density ratio. If the fiber density ratio is too high, however, an irregular dialysate path may result, thus decreasing dialysis performance. Therefore, we took note of the shape of the inner housing and added a short taper structure, which improved the dialysate path dramatically. Consequently, we developed an internal filtration-enhanced dialyzer (APS-Prototype) to improve dialysis performance. The internal filtration rate in water (measured by Doppler ultrasound) was 13.2l/session for the APS-Prototype and 5.3l/session for the APS-15E. The amount of α1-microglobulin (α1-MG) in bovine plasma was 0.34 g for the APS-Prototype and 0.11 g for the APS-15E. In addition, the amount of α1-MG in vivo was 29.0% ± 5.8% for the APS-Prototype, significantly higher than that for the APS-15E (13.6% ± 1.9%). The desirable loss of albumin is 2-4 g in hemodiafiltration, and it was 3.92 ± 1.03 g for the APS-Prototype. The prototype showed excellent solute removal performance with no clinical or engineering problems.
  • Technical evaluation of dialysate flow in a hollow-fiber dialyzer, Kei Ishiwata, Kenichiro Yamamoto, Fukashi Kohori, Kiyotaka Sakai, Makoto Fukuda, Tatsuo Hiyoshi, Journal of Artificial Organs, Journal of Artificial Organs, 5(4), 251 - 256, 2002 , Refereed
    Summary:In a hollow-fiber dialyzer, uremic toxins are removed by diffusion and convection, which are influenced by the dialysate flow patterns in the dialyzer. Recently available high-performance dialyzers have complicated dialysate flow patterns, because both positive filtration and negative filtration occur. The objective of the present study was to evaluate dialysate flow in high-performance dialyzers experimentally. Glass-coated 0.1 mmφ platinum electrodes were used for the electrode counter and the working electrode. A counter electrode was placed at the inlet of the dialyzer, and working electrodes were placed at 20 different positions. A voltage of 0.5V was applied between the counter and the working electrodes with a potentiostat, and after the dialyzer was filled with water purified by reverse osmosis, 0.9% NaCl solution was caused to flow. The time at which the 0.9% NaCl solution reached each working electrode from the counter electrode was then measured at a dialysate-side flow rate of 300ml/min and blood-side flow rates of 0 and 200 ml/min. It was found that in dialyzers with high permeability to pure water, dialysate flow was affected by both positive and negative filtration. A comparison was then made between the experimental results and the results of simulation by the finite element method at positions at which positive and negative filtration occurred, good agreement was obtained. This method makes possible the experimental evaluation of dialysate flow in a high-performance dialyzer in which positive and negative filtration occur.
  • Surface roughness of cellulose hollow fiber dialysis membranes and platelet adhesion, N Tsunoda, K Kokubo, K Sakai, M Fukuda, M Miyazaki, T Hiyoshi, ASAIO JOURNAL, ASAIO JOURNAL, 45(5), 418 - 423, Sep. 1999 , Refereed
    Summary:A great deal of research has been conducted focusing on membrane materials with reference to their blood compatibility, but blood compatibility is influenced both by the material used in membranes and their structure, and by the flow conditions at the membrane surface. Accordingly, the relationship between membrane surface roughness and hemocompatibility has been evaluated using five types of membranes of differing surface roughness by evaluating the inner surfaces of the hollow fibers by atomic force microscopy (AFM) and by measuring platelet adhesion ratios using bovine blood. The yield stress, which equates to flow characteristics, was also evaluated using a glycerol suspension of polymethylmethacrylate (PMMA), a Bingham fluid. It was found that membranes having rough surfaces had high platelet adhesion ratios and poor hemocompatibility, whereas those with smoother surfaces had lower platelet adhesion ratios and better hemocompatibility. Measurement of the yield stresses for these membranes revealed higher values far those with rough surfaces, and lower values for those with smoother polyethylene glycol (PEG) grafted surfaces. This suggests that flow conditions at the membrane surface differ according to its surface roughness, and that this difference in flow conditions also influences hemocompatibility.
  • Newly developed biocompatible membrane and effects of its smoother surface on antithrombogenicity, M Fukuda, M Miyazaki, T Hiyoshi, M Iwata, T Hongou, JOURNAL OF APPLIED POLYMER SCIENCE, JOURNAL OF APPLIED POLYMER SCIENCE, 72(10), 1249 - 1256, Jun. 1999 , Refereed
    Summary:The new biocompatible cellulosic membrane (AM-BC-F [AM-BIO-HX], Asahi-Medical Co. Ltd., Tokyo, Japan) has been developed, which has a higher flux than conventional membranes and more excellent antithrombogenicity because of its smoother membrane surface. The roughness of the inner surface of the AM-BC-F membrane was smaller than that of conventional membranes, as observed by Atomic Force Microscopy, because it was produced by the newly developed spinning method of cuprammonium cellulose solution, which has a different composition from that of a conventional cuprammonium cellulose solution. The degree of platelet adhesion (number of platelets adhered) on the membrane surface was evaluated in vitro by the measurement of the amount of the LDH released from the adhered platelets on the membrane surface after contact with fresh blood of Japanese male white rabbits weighing 2.5-3.0 kg. The number of platelets adhered of AM-BC-F was far smaller than that of conventional membranes. It was deduced from the smoother surface of the membrane. It can be expected that AM-BC-F will have an excellent antithrombogenicity on a dynamic state during actual dialysis treatments, because it is considered that the shearing stress of blood on the inner surface and the interaction between platelets and the membrane surface are less than that of conventional membrane2s. (C) 1999 John Wiley & Sons, Inc.
  • Anisotropic differences in solute transfer rate through asymmetric membranes for blood purification accompanied by filtration, M Fukuda, K Kokubo, K Sakai, G Onishi, K Takewaki, T Hiyoshi, BIOCHEMICAL ENGINEERING JOURNAL, BIOCHEMICAL ENGINEERING JOURNAL, 2(2), 127 - 136, Nov. 1998 , Refereed
    Summary:The objectives of the present study are to clarify the phenomenon of solute transfer occurring inside dialyzers made from asymmetric membranes, to examine the structure of asymmetric membranes capable of suppressing the inflow of endotoxins from the dialysate, and thereby to contribute to the design of a more effective dialysis membrane. Using membranes that have tight layers on both sides (drum-shaped membrane) with the outer one tighter, solutes are more easily transferred from the inside out than from the outside in, leading to effective removal of pathogenic substances from the blood and a significant lowering of endotoxin inflow from the dialysate. The anisotropy of solute permeability of asymmetric dialysis membranes is caused by the difference in the amount of solute transfer due to filtration from the inside out and from the outside in. (C) 1998 Elsevier Science S.A. All rights reserved.
  • STRUCTURAL-ANALYSIS OF HEMODIALYSIS MEMBRANES BY EVALUATING DISTRIBUTION VOLUME OF WATER CONTAINED IN THE MEMBRANES, T KANAMORI, M FUKUDA, K SAKAI, JOURNAL OF COLLOID AND INTERFACE SCIENCE, JOURNAL OF COLLOID AND INTERFACE SCIENCE, 171(2), 361 - 365, May 1995 , Refereed
    Summary:The distribution volume of water contained in 31 hemodialysis membranes made from seven polymers was measured by three different methods, Water contained in the membranes was classified into three groups according to thermal mobility of the molecules, Structural analysis of the membranes was feasible through determining proportion of nonfreezing water to total water contained in the membranes. (C) 1995 Academic Press, Inc.
  • PREFERABLE STRUCTURE OF POLY(ETHYLENE GLYCOL) FOR GRAFTING ONTO A CELLULOSIC MEMBRANE TO INCREASE HEMOCOMPATIBILITY WITHOUT REDUCTION IN SOLUTE PERMEABILITY OF THE MEMBRANE, T KANAMORI, K SAKAI, M FUKUDA, Y YAMASHITA, JOURNAL OF APPLIED POLYMER SCIENCE, JOURNAL OF APPLIED POLYMER SCIENCE, 55(11), 1601 - 1605, Mar. 1995 , Refereed
    Summary:Swelling layers formed by poly(ethylene glycol) (PEG) chains grafted onto surfaces of a cellulosic membrane are known to improve hemocompatibility of the membrane. Three types of hemodialysis membranes were derived from the same regenerated-cellulose hollow-fiber membrane by grafting PEG with different formulas onto the surfaces to clarify the influence of the grafted PEG chains on solute permeability of the membranes. Determination of volume fractions of nonfreezing water contained in the membranes by differential scanning calorimetry revealed that most of the PEG chains were grafted onto the external surfaces and less into the pores in the membranes. Permeability of vitamin B-12 for the PEG-grafted membranes except for the one with the shortest PEG chains was reduced as compared with the original membrane, while that of tritium-labeled water for all the PEG-grafted membranes was the same as that of the original membrane. Structural parameters only of the PEG-grafted membrane with the largest alkyl groups at the terminal of the PEG chains were different from those of the other PEG grafted and original membranes. The shorter PEG chains with the larger terminal alkyl groups are suitable for grafting onto a cellulosic membrane to increase hemocompatibility of the membrane without significant reduction in the solute permeability of the membrane. (C) 1995 John Wiley & Sons, Inc.
  • MASS-TRANSFER IN LAMINAR FLOWS AROUND SINGLE HOLLOW-FIBER MEMBRANES FOR HEMODIALYSIS, T KANAMORI, K SAKAI, T AWAKA, M FUKUDA, JOURNAL OF CHEMICAL ENGINEERING OF JAPAN, JOURNAL OF CHEMICAL ENGINEERING OF JAPAN, 27(6), 830 - 832, Dec. 1994 , Refereed
  • AN IMPROVEMENT ON THE METHOD OF DETERMINING THE SOLUTE PERMEABILITY OF HOLLOW-FIBER DIALYSIS MEMBRANES PHOTOMETRICALLY USING OPTICAL FIBERS AND COMPARISON OF THE METHOD WITH ORDINARY TECHNIQUES, T KANAMORI, K SAKAI, T AWAKA, M FUKUDA, JOURNAL OF MEMBRANE SCIENCE, JOURNAL OF MEMBRANE SCIENCE, 88(2-3), 159 - 165, Mar. 1994 , Refereed
    Summary:Absorbancy of a solution in the narrow lumen of a tubular membrane under dialysis is continuously measurable with a newly-developed apparatus using quartz optical fibers. The solute permeability of the membrane was determined by calculating time-dependent changes in the absorbancy measured with the apparatus by the mathematical solution derived for unsteady-state concentration profiles in an infinitely long composite cylinder. This method was independent of convective mass transport and osmotic flow through membranes, leading to superiority to ordinary techniques with respect to accuracy.

Conference Activities & Talks

  • 走査型プローブ顕微鏡(SPM)による血液透析膜の3次元迷宮細孔構造観察, 福田誠, 竿本仁志, 酒井清孝, 医工学治療,   2019 , 招待有り
  • 透析膜の変遷と将来, FUKUDA MAKOTO, FURUZONO TSUTOMU, 日本透析医学会雑誌,   2015 05 28 , 招待有り

Misc

  • 走査型プローブ顕微鏡(SPM)による血液透析膜の3次元迷宮細孔構造観察, 福田誠, 竿本仁志, 酒井清孝, 医工学治療, 31, Supplement, 66,   2019 , http://jglobal.jst.go.jp/public/201902243489154665
  • DFM(Dynamic Force Microscope)による血液濃縮膜の3次元迷宮細孔径測定の試み, 福田誠, 冷水大晟, 竿本仁志, 酒井清孝, 人工臓器(日本人工臓器学会), 47, 2, S.83,   2018 10 15 , http://jglobal.jst.go.jp/public/201802211835747556
  • オンラインHDF専用装置の透析液流量制御方式が血液透析濾過器におけるファウリング特性に及ぼす影響:in vitro study, 福田誠, 青松真人, 荻野紗英, 酒井清孝, 人工臓器(日本人工臓器学会), 47, 2, S.109,   2018 10 15 , http://jglobal.jst.go.jp/public/201802226359193675
  • X線CTを用いた酸素加部と熱交換部一体型膜型人工肺の非破壊構造解析と血液チャネリングの観察, 福田誠, 式田直生, 徳嶺朝子, 徳本真一, 和泉亮平, 迫田亨, 人工臓器(日本人工臓器学会), 46, 2, S.98,   2017 08 31 , http://jglobal.jst.go.jp/public/201702225272216003
  • 新規血液透析濾過膜における補液流量がファウリング特性に及ぼす影響, 福田誠, 櫻井幸尚, 小林昌平, 人工臓器(日本人工臓器学会), 46, 2, S.149,   2017 08 31 , http://jglobal.jst.go.jp/public/201702243433767012
  • 新規生体適合性膜を用いた新規血液透析濾過器のファウリング特性の評価, 福田誠, 小林昌平, 日本透析医学会雑誌, 50, Supplement 1, 588,   2017 05 28 , http://jglobal.jst.go.jp/public/201702272618426008
  • 二重境膜説におけるWilson plot法を用いたLower flux dialyzerの物質移動の解析, 福田誠, 小林昌平, 滑川亘希, 人工臓器(日本人工臓器学会), 45, 2, S.111,   2016 10 31 , http://jglobal.jst.go.jp/public/201602218061193116
  • 市販の外部灌流膜型人工肺の設計と血液流動の解析, 福田誠, 森本柾允, 徳嶺朝子, 滑川亘希, 人工臓器(日本人工臓器学会), 45, 2, S.136,   2016 10 31 , http://jglobal.jst.go.jp/public/201602269372705554
  • 透析膜の変遷と将来, 福田誠, 古薗勉, 日本透析医学会雑誌, 48, Supplement 1, 391,   2015 05 28 , http://jglobal.jst.go.jp/public/201502237119544393
  • 透析器における高血液流量での物質移動特性の検討, 福田誠, 秦弘樹, 西手芳明, 日本血液浄化技術学会雑誌, 23, 1, 104,   2015 04 01 , http://jglobal.jst.go.jp/public/201502239789756718
  • 血液流路におけるローラポンプ圧力変動がバックフロー(BF)に及ぼす影響, 福田誠, 山本和輝, 萱島道徳, 日本血液浄化技術学会雑誌, 23, 1, 108,   2015 04 01 , http://jglobal.jst.go.jp/public/201502260630823626
  • 透析工学の基礎 4)各種膜材料の特徴, 福田誠, 臨床透析, 30, 14, 1857, 1861,   2014 12 , 10.19020/J01864.2015107192, http://jglobal.jst.go.jp/public/201502215645484814
  • Mass Transfer in a Dialyzer, Fukuda Makoto, MEMBRANE, 37, 1, 10, 16,   2012 , 10.5360/membrane.37.10, http://ci.nii.ac.jp/naid/130002153194
    Summary:Removal rate of renal toxic substances in a dialyzer depends on the mass transfer rate through a dialysis membrane and in the dialysate-side boundary films. To increasing dialysis fluid-side mass transfer rate, the most important factors are jacket structure and hollow fiber shape, so newly developed dialyzers with improved jacket structure and hollow fiber shape that optimize dialysis fluid flow have been made available on the market in recent years.<br>The overall mass transfer resistance is the sum of the resistances due to the membrane itself and the thin boundary film that is formed in the fluids on both sides of the membrane (Series Boundary Film Resistance Model). The boundary film mass transfer coefficient for a fluid flowing within a straight tube has been obtained theoretically. Colburn's equation converted to mass transfer by analogy with the theoretical approximation equation that yields the boundary film coefficient of heat transmission when laminar flow occurs in a straight tube, can be used to calculate the boundary film transfer in laminar mass transfer.<br>In the present study, mass transfer correlation equations between Sherwood number (<i>Sh</i>) containing dialysis fluidside mass transfer film coefficient and Reynolds number (<i>Re</i>) were formed for newly developed dialyzers. The exponents of Re were 0.62 for APS-15S whereas approximately 0.5 for the newly developed dialyzers. The dialysis fluid-side mass transfer film coefficients of the newly developed dialyzers were higher than those of the conventional dialyzer. Based on the mass transfer correlation equations, introduction of short taper, full baffle of dialyzer jacket and further wave-shaped hollow fiber improves the dialysis fluid flow.
  • γ照射時の水分率と透析膜内表面特性の関係, 川口正晃, 滑川亘希, 松田雅人, 福田誠, 酒井清孝, 人工臓器(日本人工臓器学会), 39, 2, S92, S92,   2010 11 , http://jglobal.jst.go.jp/public/201002240580039751
  • 積層型透析器における透析液流動の評価, 上野正高, 滑川亘希, 福田誠, 酒井清孝, 平野彩香, 人工臓器(日本人工臓器学会), 39, 2, S.92,   2010 11 01 , http://jglobal.jst.go.jp/public/201002276681278182
  • 最新透析膜のPVP溶出特性, 滑川亘希, 金子亜美, 青松香里, 松田雅人, 山本健一郎, 福田誠, 酒井清孝, 人工臓器(日本人工臓器学会), 38, 2, S, 113,   2009 10 , http://jglobal.jst.go.jp/public/200902205346760802
  • ずり応力負荷による透析膜からのPVP溶出と膜表面構造の変化, 岸川竜也, 松田雅人, 滑川亘希, 山本健一郎, 薬師寺大二, 福田誠, 酒井清孝, 人工臓器(日本人工臓器学会), 38, 2, S, 113,   2009 10 , http://jglobal.jst.go.jp/public/200902288352177712
  • 透析膜内表面のタンパク質被覆によるHSA吸着力の経時的変化, 八木優, 滑川亘希, 國方賢, 松田雅人, 山本健一郎, 福田誠, 酒井清孝, 人工臓器(日本人工臓器学会), 37, 2, S, 157,   2008 11 , http://jglobal.jst.go.jp/public/200902283879658253
  • 合成高分子透析膜からのPVP溶出特性の定量的評価, 青松香里, 滑川亘希, 八木優, 松田雅人, 山本健一郎, 福田誠, 酒井清孝, 人工臓器(日本人工臓器学会), 37, 2, S, 158,   2008 11 , http://jglobal.jst.go.jp/public/200902289650921897
  • ドライタイプポリスルホン透析膜の内表面特性, 滑川亘希, 八木優, 松田雅人, 福田誠, 薬師寺大二, 宮坂武寛, 酒井清孝, 人工臓器(日本人工臓器学会), 36, 2, S48, S48,   2007 10 , http://jglobal.jst.go.jp/public/200902217168636661
  • 透析膜内表面PVPの溶出性, 阪田宏樹, 松田雅人, 薬師寺大二, 福田誠, 宮阪武寛, 山本健一郎, 酒井清孝, 人工臓器(日本人工臓器学会), 36, 2, S47, S47,   2007 10 , http://jglobal.jst.go.jp/public/200902280785785848
  • 外部灌流膜型人工肺モジュール内の血液側流動, 八木優, 山本健一郎, 酒井清孝, 薬師寺大二, 福田誠, 宮坂武寛, 人工臓器(日本人工臓器学会), 35, 2, S.143,   2006 10 01 , http://jglobal.jst.go.jp/public/200902200827550516
  • 透析器の真のTMPの測定とUFRPの経時変化の検討, 福田誠, 小川一, 薬師寺大二, 宮坂武寛, 人工臓器(日本人工臓器学会), 35, 2, S.174,   2006 10 01 , http://jglobal.jst.go.jp/public/200902264474795380
  • ウェーブ状中空糸膜と新しいハウジングを用いた透析器の性能評価, 山本健一郎, 酒井清孝, 松田雅人, 薬師寺大二, 福田誠, 宮坂武寛, 人工臓器(日本人工臓器学会), 35, 2, S88, S88,   2006 10 , http://jglobal.jst.go.jp/public/200902277444550868
  • シミュレーション解析による人工肺の至適設計, 瀬山徹, 山本健一郎, 酒井清孝, 薬師寺大二, 福田誠, 宮坂武寛, 人工臓器(日本人工臓器学会), 35, 2, S.142,   2006 10 01 , http://jglobal.jst.go.jp/public/200902294907417668
  • PVP配合量およびγ線照射量が湿潤透析膜表面のタンパク質吸着特性に与える影響, 松田雅人, 山本健一郎, 酒井清孝, 薬師寺大二, 福田誠, 宮坂武寛, 人工臓器(日本人工臓器学会), 35, 2, S87, S87,   2006 10 , http://jglobal.jst.go.jp/public/200902298331620735
  • APS‐SA透析器における透析液流動状態の評価, 山本健一郎, 薬師寺大二, 小堀深, 酒井清孝, 福田誠, 人工臓器(日本人工臓器学会), 34, 2, S.189,   2005 11 15 , 10.11392/jsao1972.34.2Supplement_s189, http://jglobal.jst.go.jp/public/200902217279923198
  • 新しいAPSダイアライザ(APS‐SAシリーズ)の設計, 福田誠, 人工臓器(日本人工臓器学会), 34, 2, S, 189,   2005 11 , 10.11392/jsao1972.34.2Supplement_s189a, http://jglobal.jst.go.jp/public/200902299541889369
  • 内部ろ過促進型ダイアライザー, 福田誠, 宮崎美和, 上住敏士, 日吉辰夫, 内幸彦, 藤村崇保, 人工臓器(日本人工臓器学会), 33, 3, 288, 290,   2004 12 15 , 10.11392/jsao1972.33.288, http://jglobal.jst.go.jp/public/200902230553989202
  • 低分子蛋白除去量を向上させた内部ろ過促進型ダイアライザー(APS‐Prototype)の開発, 藤村崇保, 内幸彦, 福田誠, 宮崎美和, 上住敏士, 日吉辰夫, 人工臓器(日本人工臓器学会), 32, 2, S.119,   2003 09 15 , http://jglobal.jst.go.jp/public/200902252860309328
  • ポリスルホン透析膜のクッション効果による生体適合性向上, 葉山順代, 山本健一郎, 小堀深, 酒井清孝, 福田誠, 日吉辰夫, 人工臓器(日本人工臓器学会), 32, 2, S119, S119,   2003 09 , http://jglobal.jst.go.jp/public/200902221190590508
  • 乾燥・湿潤による透析膜表面構造変化の観察, 葉山順代, 山本健一郎, 小堀深, 福田誠, 日吉辰夫, 酒井清孝, 人工臓器(日本人工臓器学会), 31, 2, S138, S138,   2002 09 , http://jglobal.jst.go.jp/public/200902154083333765
  • Impact of three-dimensional tortuous pore structure on polyethersulfone membrane morphology and mass transfer properties from a manufacturing perspective(和訳中), Fukuda Makoto, Saomoto Hitoshi, Yoshimoto Hiroki, Kusumi Rei, Sakai Kiyotaka, 人工臓器, 48, 2, S, 137,   2019 10
  • EFFECTS OF TAPER STRUCTURE OF DIALYZER JACKET ON DIALYSIS FLUID FLOW, K. Yamamoto, N. Takizawa, M. Matsuda, T. Yakushiji, M. Fukuda, T. Miyasaka, K. Sakai, INTERNATIONAL JOURNAL OF ARTIFICIAL ORGANS, 31, 7, 642, 643,   2008 07

Awards & Honors

  •   2009 , the Japanese Society of Artificial Organs (JSAO), the society's article awards