論文 - 藤本　啓二

Interactions between thermosensitive hydrogel microspheres and proteins

Fujimoto,K., Mizuhara,Y., Tamura,N., and Kawaguchi,H.

Journal of Intelligent Material Systems and Structures （Journal of Intelligent Material Systems and Structures）  vol.4 （ 2 ） 184-189 - 189 1993年

研究論文（学術雑誌）, 共著, 査読有り,  ISSN  1045389X

　概要を見る

感温性ゲル微粒子への様々なタンパク質の吸着現象について検討を行った。

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Ozone-induced graft polymerization onto polymer surface

Fujimoto,K., Takebayashi,Y., Inoue,H., and Ikada,Y.

Journal of Polymer Science, Polymer Chemistry Edition vol.31   1035-1043 1993年

共著, 査読有り

　概要を見る

オゾンで高分子物質を処理することによって、その表面への多種類のポリマー鎖のグラフト化が可能となった。

Polyurethane surface modification by graft polymerization of acrylamide for reduced protein adsorption and platelet adhesion

Fujimoto,K., Tadokoro,H., Ueda,Y., and Ikada,Y.

Biomaterials （Biomaterials）  vol.14 （ 6 ） 442-448 - 448 1993年

研究論文（学術雑誌）, 共著, 査読有り,  ISSN  01429612

　概要を見る

ポリウレタンを低温プラズマ処理し、表面へのアクリルアミドのグラフト重合を行った。この改質により表面へのタンパク質の吸着および血小板の粘着は著しく抑制された。

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Protein adsorption and platelet adhesion onto polyurethane grafted with methoxy-poly(ethylene glycol)methacrylate by plasma technique

Fujimoto,K., Inoue,H., and Ikada,Y.

Journal of Biomedical Material Research vol.27   1559-1567 1993年

共著, 査読有り

　概要を見る

ポリウレタンを低温プラズマ処理し、表面への側鎖にポリエチレンオキサイドを有するビニルモノマーのグラフト重合を行った。この改質により表面へのタンパク質の吸着および血小板の粘着は著しく抑制された。

Platelet deposition onto polymeric surfaces during shunting

Fujimoto,K., Minato,M., Tadokoro,H., and Ikada,Y.

Journal of Biomedical Materials Research （Journal of Biomedical Materials Research）  vol.27 （ 3 ） 335-343 - 343 1993年

研究論文（学術雑誌）, 共著, 査読有り,  ISSN  00219304

　概要を見る

様々な高分子物質からなる小口径のチューブを用いて、動脈-静脈シャントを行い、主に血小板粘着挙動を調べた。

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Porous polyurethane tubes as vascular graft.

Fujimoto,K., Minato,M., Miyamoto,S., Kaneko,T., Kikuchi,H., Sakai,K.,Okada,M., and Ikada,Y.

Journal of applied biomaterials : an official journal of the Society for Biomaterials （Journal of applied biomaterials : an official journal of the Society for Biomaterials）  vol.4 （ 4 ） 347-354 - 354 1993年

研究論文（学術雑誌）, 共著, 査読有り,  ISSN  10454861

　概要を見る

ポリウレタンから多孔性のチューブを作製し、そのポアサイズが大きいほど開存率が高いという結果を見いだした。

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Preparation of peptide-carrying microspheres with bioactivity on platelet

Kasuya,Y., Fujimoto,K., Miyamoto,M., Juji,T., Otaka,A., Funakoshi,S., Fujii,N., and Kawaguchi,H.

Journal of Biomaterials Science, Polymer Edition vol.4   369-380 1993年

共著, 査読有り

　概要を見る

細胞接着成分であるテトラペプチドを結合させた微粒子を作製し、血小板への作用を見た。この微粒子は血小板を有為に凝集させることがわかった。

Application of Hydrogel Microspheres to Latex Diagnosis

Akazawa T., Fujimoto K., Kawaguchi H.

Kobunshi Ronbunshu （Kobunshi Ronbunshu）  50 （ 5 ） 431 - 435 1993年

研究論文（学術雑誌）, 査読有り,  ISSN  03862186

　概要を見る

Acrylamide, glycidyl methacrylate, and methylene bisacrylamide were copolymerized in an aqueous ethanol to form monodisperse hydrogel latex particles. Antibody of C-reactive protein (CRP) was immobilized on the particles through a hydrophilic spacer. The resulting particles were moderately stable, and the agglutination was proportional to the concentration of CRP. They were little susceptible to the nonspecific adsorption of proteins and the aggregation by rheumatoid factor. Therefore, it was concluded that the hydrogel particles are a promising carrier of antibodies for latex diagnosis. © 1993, The Society of Polymer Science, Japan. All rights reserved.

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Preparation of peptide-carrying microspheres with bioactivity on platelets

Kasuya Y., Fujimoto K., Kawaguchi H., Miyamoto M., Juji T., Otaka A., Funakoshi S., Fujii N.

Journal of Biomaterials Science, Polymer Edition （Journal of Biomaterials Science, Polymer Edition）  4 （ 3 ） 369 - 380 1993年

研究論文（学術雑誌）, 査読有り,  ISSN  09205063

　概要を見る

A tetrapeptide RGDS (Arg-Gly-Asp-Ser), which is one of the active sites of cell adhesive proteins, was synthesized according to the solution method and covalently coupled onto monodisperse microspheres. The biospecific activity of the RGDS-carrying microspheres was investigated by measuring the stimulatory effect of the microspheres on platelets. Large and tightly packed platelet aggregation accompanied with drastic ATP release was induced by the RGDS-carrying microspheres. It was confirmed that the specific platelet aggregation was attributed to the activity of the immobilized RGDS by comparison with those induced by other microspheres. © VSP 1993.

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Preparation Of Peptide-Carrying Microspheres With Bioactivity On Platelets

Kasuya Y., Fujimoto K., Kawaguchi H., Miyamoto M., Juji T., Otaka A., Funakoshi S., Fujii N.

Journal of Biomaterials Science, Polymer Edition （Journal of Biomaterials Science, Polymer Edition）  4 （ 4 ） 369 - 380 1993年

研究論文（学術雑誌）, 査読有り,  ISSN  09205063

　概要を見る

A tetrapeptide RGDS (Arg-Gly-Asp-Ser), which is one of the active sites of cell adhesive proteins, was synthesized according to the solution method and covalently coupled onto monodisperse microspheres. The biospecific activity of the RGDS-carrying microspheres was investigated by measuring the stimulatory effect of the microspheres on platelets. Large and tightly packed platelet aggregation accompanied with drastic ATP release was induced by the RGDS-carrying microspheres. It was confirmed that the specific platelet aggregation was attributed to the activity of the immobilized RGDS by comparison with those induced by other microspheres. © 1993, VSP. All rights reserved.

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Preparation and Evaluation of Polymer Microspheres with Cell Adhesion Activity

Kasuya Y., Shimizu K., Fujimoto K., Kawaguchi H., Miyamoto M., Otaka A., Funakoshi S., Fujii N.

Kobunshi Ronbunshu （Kobunshi Ronbunshu）  50 （ 5 ） 417 - 423 1993年

研究論文（学術雑誌）, 査読有り,  ISSN  03862186

　概要を見る

Microspheres having cell adhesion activity were prepared by immobilizing a tetrapeptide Arg-Gly-Asp-Ser (RGDS) onto the surface. Phagocytosis of the microspheres by leukocytes was not enhanced by immobilizing RGDS, but specific oxygen consumption was observed during the incubation of the RGDS-carrying microspheres with leukocytes. This was enhanced by a spacer introduced between RGDS and the microsphere. These results suggested that the immobilized RGDS could transduce the adhesion signal, resulting in the activation of leukocytes without enhancing phagocytosis of the microspheres. Furthermore, it was found that soluble RGDS did not induce oxygen consumption at all by itself. This result suggests that RGDS must be immobilized on solid carriers for the specific activation of leukocytes. Preparation and Evaluation of Polymer Microspheres with Cell Adhesion Activity. © 1993, The Society of Polymer Science, Japan. All rights reserved.

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Fluorescence analysis for thermo‐sensitive hydrogel microspheres

Fujimoto K., Nakajima Y., Kashiwabara M., Kawaguchi H.

Polymer International （Polymer International）  30 （ 2 ） 237 - 241 1993年

研究論文（学術雑誌）, 査読有り,  ISSN  09598103

　概要を見る

Poly(N‐isopropylacrylamide) (PNIPAM) hydrogel microspheres were prepared by precipitation polymerization above the polymer's lower critical solution temperature (LCST) in water. The hydrodynamic size of PNIPAM microspheres exhibited a thermo‐sensitive change around the LCST. In order to obtain information about the interface of the hydrogels, contact angle measurement, protein adsorption, and fluorescence analysis were performed. Contact angle measurement and protein adsorption showed a gradual change around the LCST similar to the change of the hydrodynamic size. However, fluorescence study exhibited a sharp change at the LCST. In addition, a quenching experiment was employed to elucidate the location of the fluorescent probes. In the PNIPAM latex, the probes were located where they were less quenchable as compared to the PNIPAM solution. It seems probable that the probes can penetrate into the crosslinked PNIPAM hydrogel and might reflect the inner environment of the hydrogel. The effect of salt on thermo‐sensitive behaviour was also detected by fluorescence analysis. On the other hand, the hydrogel microsphere prepared from poly(acryloyl pyrrolidine) (PAPr) showed a gradual change in fluorescence with temperature. Copyright © 1993 Society of Chemical Industry

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Hydrogel microspheres III. Temperature-dependent adsorption of proteins on poly-N-isopropylacrylamide hydrogel microspheres

Kawaguchi H., Fujimoto K., Mizuhara Y.

Colloid & Polymer Science （Colloid & Polymer Science）  270 （ 1 ） 53 - 57 1992年01月

研究論文（学術雑誌）, 査読有り,  ISSN  0303402X

　概要を見る

Precipitation polymerization of N-isopropylacrylamide (NIPAM) with methylenebisacrylamide (MBAAm) in water at 70°C gave thermosensitive hydrogel microspheres. The adsorbability of proteins on the poly-NIPAM microspheres was found to depend on temperature. Below the lower critical solution temperature (LCST) of poly-NIPAM in an aqueous medium, that is, around 32°C, the microspheres hold a large amount of water inside and their surface is hydrophilic enough to suppress the adsorption of proteins. On the contrary, above 32°C, the micropheres deswell and their surface becomes hydrophobic and, consequently, susceptible to adsorption of a large amount of proteins. Proteins once adsorbed on the microspheres at a high temperature could be desorbed more or less by lowering the temperature to below 32°C. The extent of desorption at low temperatures was found to depend on the incubation time for adsorption at high temperatures. © 1992 Steinkopff-Verlag.

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Hydrogel microspheres 3. Temperature-dependent adsorption of proteins on poly(N-isopropylacrylamide) hydrogel microspheres

Kawaguchi,H., Fujimoto,K., and Mizuhara,Y.

Colloid & Polymer Science vol.270   53-57 1992年

共著, 査読有り

　概要を見る

温度変化によってポリマー鎖が収縮して粒子径が変化する微粒子を作製し、その表面へのタンパク質の吸着挙動を調べた。

Improvement in the mechanical properties of artificial blood vessel suitable for the extracranial cerebral artery

Miyamoto,S., Kikuchi,H., Ikada,Y., Minato,M., Fujimoto,K., Okada,M., Sakai,K., Nagata,I., Yamagata,S., Kaneko,T., and Kubo,H.

Neurological Surgery （Neurological Surgery）  vol.18 （ 3 ） 253-258 - 258 1990年

研究論文（学術雑誌）, 共著, 査読有り,  ISSN  03012603

　概要を見る

ポリウレタンからなる人工血管を用いて埋植実験を行い、その機械的性質が重要である結果を得た。

Blood compatibility of polyurethane modified by surface graft polymerization

Fujimoto K., Tadokoro H., Minato M., Ikada Y.

Polymeric Materials Science and Engineering, Proceedings of the ACS Division of Polymeric Materials Science and Engineering （Polymeric Materials Science and Engineering, Proceedings of the ACS Division of Polymeric Materials Science and Engineering）  62   736 - 740 1990年

研究論文（学術雑誌）, 査読有り,  ISSN  07430515

　概要を見る

The purpose of this work is to modify PU by surface graft polymerization of acrylic monomers so as to reduce protein adsorption and platelet adhesion. It is shown that there is an optimum in the graft amount which leads to the minimum protein adsorption and thrombus formation.

Comparison between plasma- and ozone-induced graft polymerization

Fujimoto K., Ueda Y., Takebayashi Y., Ikada Y.

Polymeric Materials Science and Engineering, Proceedings of the ACS Division of Polymeric Materials Science and Engineering （Polymeric Materials Science and Engineering, Proceedings of the ACS Division of Polymeric Materials Science and Engineering）  62   284 - 288 1990年

研究論文（学術雑誌）, 査読有り,  ISSN  07430515

　概要を見る

This paper describes the results of plasma- and ozone-induced graft polymerization of acrylamides, together with the amount of peroxides formed by the plasma treatment and the ozonization. It is concluded that both the treatments of polymer surfaces by plasma and ozone produce polymeric peroxides which are capable of initiating graft polymerization, even if the treatments are conducted under a mild condition. An advantage of the ozonization over the plasma treatment is easy and uniform introduction of peroxides on the surface of molded products even with complicated shapes.

New veno-venous bypass without systemic anticoagulation in canine liver transplantation

Kim,K.S., Ueda,J., Asonuma,K., Zaima,M.,Tanaka,K., Ozawa,K., Minato,M.,Fujimoto,K., and Ikada,Y.

Surgery Research Communication vol.6   287-298 1989年

共著, 査読有り

　概要を見る

全身的な抗凝血剤処置を行わずに肝臓移植を行うための、新規の静脈-静脈バイパス技術を開発した。