Faculty Profiles - UCHIDA Tetsuya

Papers - UCHIDA Tetsuya

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Development and chemical properties of retinal prostheses using photoelectric dyes coupled to polyethylene films with various anions to achieve high durability Reviewed

Koichiro Yamashita, Tenu Tanaka, Toshihiko Matsuo, Tetsuya Uchida

POLYMER JOURNAL 53 ( 6 ) 719 - 729 2021.6

Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：SPRINGERNATURE

Photoelectric dyes, which absorb light and generate electric potential, have been shown to stimulate retinal neurons. Therefore, in the present work, a photoelectric dye was used to develop a retinal prosthesis to restore vision loss due to diseases, such as retinitis pigmentosa. The retinal prosthesis, referred to as a dye-coupled film, was prepared by chemically coupling the dyes to a polyethylene film surface. However, the amount of coupled dye decreased during an implantation test in a monkey's eye. The dye consisted of a cation with photoresponsivity and Br-. Because thermal stability can be improved by anion exchange, we expected anion exchange to lead to stabilization of the chemical structure, resulting in improvement of the long-term durability of a retinal prosthesis. Therefore, the effects of exchanging Br- anions for PF6-, BF4-, and bis(trifluoromethanesulfonyl)imide (TFSI-) anions on the durability were investigated. The long-term durability of the dye-coupled films was found to be strongly related to the thermal stability of the photoelectric dye. The long-term durability of the dye-coupled film-PF6- and dye-coupled film-TFSI- improved by 637 and 215%, respectively, compared with that of the dye-coupled film-Br-.

DOI： 10.1038/s41428-021-00468-0

Crystallization of single-walled carbon nanotubes from a dilute solution Reviewed

Tetsuya Uchida, Naoya Tsugawa, Satoru Yoshida, Natsuki Tohnai

POLYMER 216 2021.2

Authorship：Lead author,　Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：ELSEVIER SCI LTD

Single-walled carbon nanotubes (SWNTs) with lengths of several hundred nanometers were crystallized from dilute solutions, and slender lath-shaped SWNT crystals were obtained. The SWNTs were oriented along the long axis of the lath-shaped crystal, and the obtained crystals were two-dimensional crystals comprising hexagonally close-packed SWNTs. A relatively long SWNT acted as a crystalline nucleus. The length of the SWNT used for crystallization affected the morphology and growth rate of the crystals. Higher crystallization temperature shortened the time to precipitation, and the diffusion of SWNTs dominated the crystal growth of SWNT crystals. Because the short SWNTs were rigid with a wide length distribution, their tube ends were inevitably included in the crystals, resulting in crystal defects, such as lattice curvature and edge dislocations. These defects were directly observed by high-resolution electron microscopy. The mechanism for the crystallization of the SWNTs was proposed based on the observed morphologies, crystal defects, and crystallization process.

DOI： 10.1016/j.polymer.2021.123425

Preparation of solution-grown lozenge-shaped poly(p-phenylene terephthalamide) single crystals and their structural stabilization by heat treatment Reviewed

Tetsuya Uchida, Yutaro Hara, Tomoyasu Takaki

POLYMER 202 2020.8

Authorship：Lead author,　Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：ELSEVIER SCI LTD

In this study, the preparation of poly (p-phenylene terephthalamide) (PPTA) single crystals was examined using crystallization from dilute solutions in concentrated sulfuric acid. Lozenge-shaped PPTA single crystals were successfully prepared using a self-seeding method with a low degree of supercooling, and they consisted of modification I crystals. The a-axis direction of the crystal corresponded to the long diagonal direction of the rhombus, the b-axis direction with the short diagonal direction, and the PPTA molecular chain direction (the c-axis direction) with the crystal's thickness direction. In addition, the PPTA single crystals had a (110) growth plane, where the thickness of each single crystal was approximately equal to the molecular chain length of the PPTA. Upon heat treatment of the PPTA single crystals, the symmetry changed from P1a1 to the more stable P11n. In addition, the heat treatment caused a difference in the density of each symmetric crystal, resulting in crack formation along the b-axis direction, which is the hydrogen-bonding direction. However, the heat treatment did not change the thickness of the PPTA single crystals. Conversely, the isothermal crystallization of the PPTA caused progression in the crystallization only under a high degree of supercooling, thus yielding plate-like PPTA crystals that consisted of modification II crystals. In these plate-like PPTA crystals, the length corresponded to the crystal a-axis direction, and the electron diffraction pattern was broad. Furthermore, the equilibrium dissolution temperature of the PPTA single crystals was discussed.

DOI： 10.1016/j.polymer.2020.122672

Curved-Tip Disposable Injector (OUReP Injector) to Insert Photoelectric Dye-Coupled Polyethylene Film (OUReP) as Retinal Prosthesis into Subretinal Space of Rabbit Eyes Reviewed

Toshihiko Matsuo, Chie Matsuo, Tetsuya Uchida, Koichiro Yamashita, Tenu Tanaka, Yusuke Kawakami, Toshiya Hitomi, Kanji Taga, Tatsuya Sanada, Yusuke Yamashita

Journal of Surgical Techniques and Procedures 4 1040 2020.7

Step-by-Step Procedure to Test Photoelectric Dye-Coupled Polyethylene Film as Retinal Prosthesis to Induce Light-Evoked Spikes in Isolated Retinal Dystrophic Tissue of rd1 Mice Reviewed

Toshihiko Matsuo, Keiko Terada, Mikako Sakurai, Shihui Liu, Koichiro Yamashita, Tetsuya Uchida

Clinics in Surgery 5 2903 2020.5

Vision evaluation by functional observational battery, operant behavior test, and light/dark box test in retinal dystrophic RCS rats versus normal rats Reviewed

Toshihiko Matsuo, Tetsuya Uchida, Koichiro Yamashita, Shigiko Takei, Daisuke Ido, Atsushi Fujiwara, Masahiko Iino, Masao Oguchi

HELIYON 5 ( 6 ) 2019.6

Language：English Publishing type：Research paper (scientific journal) Publisher：ELSEVIER SCI LTD

Background: Vision plays a key role in some behavior tests for rats. Okayama University-type retinal prosthesis (OUReP) is a photoelectric dye-coupled polyethylene film which generates electric potential in response to light and stimulates nearby neurons. This study aims to assess vision in retinal dystrophic (RCS) rats, in comparison with normal rats, by selected behavior tests. We also examined whether the tests could detect vision changes in RCS rats with dye-coupled film implantation.Methods: Data sets were 5 normal rats, 4 untreated RCS rats, 7 RCS rats with dye-coupled films implanted at the age of 7 weeks after excluding unsuccessful implantation at autopsy. Behavior tests chosen were landing foot splay and visual forelimb-placing response in the menu of functional observational battery, operant-conditioning lever-press response and light/dark box test.Results: Normal visual placing response was significantly less frequent in untreated RCS rats at the age of 9 and 11 weeks, compared with normal rats (P = 0.0027, chi-square test) while normal response was significantly more frequent at the age of 9 weeks in RCS rats with dye-coupled film implantation, compared with untreated RCS rats (P = 0.0221). In operant-conditioning lever-press test, the correct response rate was significantly lower in untreated RCS rats than in normal rats at the age of 9 weeks (P < 0.05, Tukey-Kramer test) while the rate was not significantly different between normal rats and RCS rats with dye-coupled film implantation. In light/dark box test, the time to enter dark box was significantly shorter in normal rats, compared with untreated RCS rats or RCS rats with dye-coupled film implantation (P < 0.05, Tukey-Kramer test).Conclusions: Behavior tests of functional observational battery, operant-conditioning lever-press response and light/dark box test discriminated vision between normal rats and RCS rats. The visual placing response and operant-conditioning lever-press test might have sensitivity to detect vision recovery in RCS rats with OUReP implantation.

DOI： 10.1016/j.heliyon.2019.e01936

Photoelectric Dye-Coupled Polyethylene Film: Photoresponsive Properties Evaluated by Kelvin Probe and In Vitro Biological Response Detected in Dystrophic Retinal Tissue of Rats Reviewed

Toshihiko Matsuo, Mikako Sakurai, Keiko Terada, Tetsuya Uchida, Koichiro Yamashita, Tenu Tanaka, Kenichi Takarabe

ADVANCED BIOMEDICAL ENGINEERING 8 137 - 144 2019

Language：English Publishing type：Research paper (scientific journal) Publisher：JAPANESE SOC MEDICAL & BIOLOGICAL ENGINEERING

Electrodes that output electric current as conduction current are widely used to stimulate nerves and cardiac cells in human body. We designed a photoelectric dye-coupled polyethylene film for use as a thin film device to stimulate nerve cells by electric potential changes. The aim of this study was to measure its photo-responsive properties and to record in vitro biological response. When measured using a Kelvin probe system, the photoelectric dye-coupled film showed rapid rise and fall of surface electric potential in response to light-on-and-off. Light-evoked surface electric potential of the dye-coupled film increased in response to increasing light intensity. In vitro biological response to the dye-coupled film was assessed in isolated rat retinal tissues using a multielectrode array recording system. As positive control, electroretinogram-like waves were recorded in response to light from normal rat retinal tissue placed with the inner retinal surface at the bottom of the multielectrode array dish. In contrast, no light-elicited wave was recorded from degenerative retinal tissue isolated from retinal dystrophic Royal College of Surgeons (RCS) rats. When the dye-coupled film was simply overlaid on the degenerative retinal tissue with the inner retinal surface placed at the bottom of the multielectrode array dish, electroretinogram-like waves were elicited in response to light projected from the bottom. Plain polyethylene film without photoelectric dye coupling was used as negative control, and did not yield light-elicited response when placed on the degenerative retinal tissue. For detailed recordings of action potential spikes high-passed at 100 Hz, a nylon mesh anchor was placed on top of the preparation to ensure close contact between the multielectrode array and the retinal tissue with or without the dye-coupled film. In this experimental setting, the degenerative retinal tissue alone showed spontaneous action potential spikes as numerous small trivial amplitudes in the background noise, while the degenerative retinal tissue overlain with the dye-coupled film showed action potential spikes with increased amplitude in response to light against the background of spontaneous spikes. This study confirmed that the photoelectric dye-coupled polyethylene film is able to stimulate degenerative retinal tissue that has lost photoreceptor cells, and may function as a novel type of retinal prosthesis. Electric potential changes, probably as displacement current or capacitive current, may be an alternative approach to stimulate nerves in human body.

DOI： 10.14326/abe.8.137

Development of High-Performance Nanofibers by Using Crystallization from Dilute Solution and Their Application in Composites

Tetsuya Uchida

SEN-I GAKKAISHI 74 ( 10 ) P489 - P492 2018.10

Visual Evoked Potential Recovery by Subretinal Implantation of Photoelectric Dye-Coupled Thin Film Retinal Prosthesis in Monkey Eyes With Macular Degeneration Reviewed

Toshihiko Matsuo, Tetsuya Uchida, Jun Sakurai, Koichiro Yamashita, Chie Matsuo, Tomoaki Araki, Yusuke Yamashita, Kunihisa Kamikawa

ARTIFICIAL ORGANS 42 ( 8 ) E186 - E203 2018.8

Language：English Publishing type：Research paper (scientific journal) Publisher：WILEY

Retinal prosthesis or artificial retina is a promising modality of treatment for outer retinal degeneration, caused by primary and secondary loss of photoreceptor cells, in hereditary retinal dystrophy and age-related macular degeneration, respectively. Okayama University-type retinal prosthesis (OUReP) is a photoelectric dye-coupled polyethylene film which generates electric potential in response to light and stimulates nearby neurons. The dyecoupled films were implanted by vitreous surgery in the subretinal space of monkey eyes with macular degeneration which had been induced by cobalt chloride injection from the scleral side. A pilot 1-month observation study involved 6 monkeys and a pivotal 6-month observation study involved 8 monkeys. Of 8 monkeys in 6-month group, 3 monkeys underwent dye-coupled film removal at 5 months and were observed further for 1 month. The amplitude of visual evoked potential which had been reduced by macular degeneration did recover at 1 month after film implantation and maintained the level at 6 months. Optical coherence tomography showed no retinal detachment, and full-field electroretinograms maintained a-wave and b-wave amplitudes, indicative of no retinal toxicity. Pathological examinations after 6-month implantation showed structural integrity of the inner retinal layer in close apposition to dye-coupled films. The implanted films which were removed by vitrectomy 5 months later showed light-evoked surface electric potentials by scanning Kelvin probe measurement. The photoelectric dye-coupled film (OUReP), which serves as a light-receiver and a displacement current generator in the subretinal space of the eye, has a potential for recovering vision in diseases with photoreceptor cell loss, such as retinitis pigmentosa and age-related macular degeneration.

DOI： 10.1111/aor.13120

Novel disposable injector (OUReP Injector) tested in rabbits’ eyes for subretinal implantation of Okayama University-type retinal prosthesis (OUReP) Reviewed

T.Matsuo, T.Uchida, K.Yamashita, C.Matsuo, Y.Kawakami, T.Hitomi, K.Taga, T.Sanada, Y.Yamashita, K.Kuramoto

Anim. Eye Res. 37 3 - 12 2018.7

Visual evoked potential in rabbits' eyes with subretinal implantation by vitrectomy of Okayama University-type retinal prosthesis (OUReP (TM)) Reviewed

Toshihiko Matsuo, Tetsuya Uchida, Koichiro Yamashita, Shigiko Takei, Daisuke Ido, Mamoru Tanaka, Masao Oguchi, Toshinori Furukawa

JOURNAL OF VETERINARY MEDICAL SCIENCE 80 ( 2 ) 247 - 259 2018.2

Language：English Publishing type：Research paper (scientific journal) Publisher：JAPAN SOC VET SCI

Okayama University-type retinal prosthesis (OURePTM) is a photoelectric dye-coupled polyethylene film which generates electric potential in response to light and stimulates nearby neurons. This study aims to test surgical feasibility for subretinal film implantation and to examine functional durability of films in subretinal space. Dye-coupled films were implanted subretinally by vitrectomy in the right eye of normal white rabbits: 8 rabbits for 1 month and 8 rabbits for 6 months. The implanted films were removed by vitrectomy in 4 of these 8 rabbits in 1-month or 6-month implantation group. The films were also implanted in 4 rhodopsin-transgenic retinal dystrophic rabbits. Visual evoked potential was measured before film implantation as well as 1 or 6 months after film implantation, or 1 month after film removal. The films were successfully implanted in subretinal space of retinal detachment induced by subretinal fluid injection with a 38G polyimide tip. The retina was reattached by fluid-air exchange in vitreous cavity, retinal laser coagulation, and silicone oil injection. The ratios of P-2 amplitudes of visual evoked potential in the implanted right eye over control left eye did not show significant changes between pre-implantation and post-implantation or post-removal (paired t-test). In Kelvin probe measurements, 4 pieces each of removed films which were implanted for 1 or 6 months showed proportional increase of surface electric potential in response to increasing light intensity. The film implantation was safe and implanted films were capable of responding to light.

DOI： 10.1292/jvms.17-0422

Amino group in Leptothrix sheath skeleton is responsible for direct deposition of Fe(III) minerals onto the sheaths Reviewed

Tatsuki Kunoh, Syuji Matsumoto, Noriyuki Nagaoka, Shoko Kanashima, Katsuhiko Hino, Tetsuya Uchida, Katsunori Tamura, Hitoshi Kunoh, Jun Takada

SCIENTIFIC REPORTS 7 ( 1 ) 141 - 149 2017.7

Language：English Publishing type：Research paper (scientific journal) Publisher：NATURE PUBLISHING GROUP

Leptothrix species produce microtubular organic-inorganic materials that encase the bacterial cells. The skeleton of an immature sheath, consisting of organic exopolymer fibrils of bacterial origin, is formed first, then the sheath becomes encrusted with inorganic material. Functional carboxyl groups of polysaccharides in these fibrils are considered to attract and bind metal cations, including Fe(III) and Fe(III)-mineral phases onto the fibrils, but the detailed mechanism remains elusive. Here we show that NH2 of the amino-sugar-enriched exopolymer fibrils is involved in interactions with abiotically generated Fe(III) minerals. NH2-specific staining of L. cholodnii OUMS1 detected a terminal NH2 on its sheath skeleton. Masking NH2 with specific reagents abrogated deposition of Fe(III) minerals onto fibrils. Fe(III) minerals were adsorbed on chitosan and NH2-coated polystyrene beads but not on cellulose and beads coated with an acetamide group. X-ray photoelectron spectroscopy at the N1s edge revealed that the terminal NH2 of OUMS1 sheaths, chitosan and NH2-coated beads binds to Fe(III)-mineral phases, indicating interaction between the Fe(III) minerals and terminal NH2. Thus, the terminal NH2 in the exopolymer fibrils seems critical for Fe encrustation of Leptothrix sheaths. These insights should inform artificial synthesis of highly reactive NH2-rich polymers for use as absorbents, catalysts and so on.

DOI： 10.1038/s41598-017-06644-8

Visual evoked potential in RCS rats with Okayama University-type retinal prosthesis (OUReP (TM)) implantation Reviewed

Alamusi, Toshihiko Matsuo, Osamu Hosoya, Tetsuya Uchida

JOURNAL OF ARTIFICIAL ORGANS 20 ( 2 ) 158 - 165 2017.6

Language：English Publishing type：Research paper (scientific journal) Publisher：SPRINGER JAPAN KK

Photoelectric dye-coupled polyethylene film, designated Okayama University type-retinal prosthesis or OUReP (TM), generates light-evoked surface electric potentials and stimulates neurons. The dye-coupled films or plain films were implanted subretinally in both eyes of 10 Royal College of Surgeons rats with hereditary retinal dystrophy at the age of 6 weeks. Visual evoked potentials in response to monocular flashing light stimuli were recorded from cranially-fixed electrodes, 4 weeks and 8 weeks after the implantation. After the recording, subretinal film implantation was confirmed histologically in 7 eyes with dye-coupled films and 7 eyes with plain films. The recordings from these 7 eyes in each group were used for statistical analysis. The amplitudes of visual evoked potentials in the consecutive time points from 125 to 250 ms after flash were significantly larger in the 7 eyes with dye-coupled film implantation, compared to the 7 eyes with plain film implantation at 8 weeks after the implantation (P < 0.05, repeated-measure ANOVA). The photoelectric dye-coupled polyethylene film, as retinal prosthesis, gave rise to visual evoked potential in response to flashing light.

DOI： 10.1007/s10047-016-0943-4

Photoelectric Dye Used for Okayama University-Type Retinal Prosthesis Reduces the Apoptosis of Photoreceptor Cells Reviewed

Shihui Liu, Toshihiko Matsuo, Osamu Hosoya, Tetsuya Uchida

JOURNAL OF OCULAR PHARMACOLOGY AND THERAPEUTICS 33 ( 3 ) 149 - 160 2017.4

Language：English Publishing type：Research paper (scientific journal) Publisher：MARY ANN LIEBERT, INC

Purpose: Our previous study demonstrated that photoelectric dye-coupled polyethylene film (Okayama University-type retinal prosthesis), which was implanted in subretinal space of the eyes of Royal College of Surgeons (RCS) rats, prevented retinal neurons from apoptotic death. In this study, we aimed to examine whether photoelectric dye itself would protect retinal neurons from apoptosis in RCS rats.Methods: RCS rats received intravitreous injection of different concentrations of the dye in the left eye and housed under a 12-h light-dark cycle. Saline injection in the right eye served as control. In addition, RCS rats with dye injection were kept in 24-h daily dark condition. Sections were processed for terminal deoxynucleotidyl transferase-mediated fluorescein-conjugated-dUTP nick-end-labeling (TUNEL) assay and immunohistochemical staining of glial fibrillary acidic protein (GFAP) and protein kinase C alpha (PKC alpha).Results: The number of TUNEL-positive cells significantly decreased in the retina of dye-injected eyes compared with those in saline-injected eyes (P = 0.0001, 2-factor analysis of variance [ANOVA]), under 12-h light-dark cycle. Significant decrease of TUNEL-positive cells was noted in the retina of rats with dye injection compared with those with saline injection, kept under 24-h dark condition (P = 0.0001, 2-factor ANOVA). Immunoreactive area for GFAP decreased significantly in the retina of dye-injected eyes compared with that in controls (P = 0.0001, 2-factor ANOVA), whereas immunoreactive area for PKCa increased significantly in the retina of dye-injected eyes compared with that in controls (P = 0.01, 2-factor ANOVA).Conclusions: Photoelectric dye inhibits apoptotic death of photoreceptor cells in RCS rats and downregulates GFAP expression in retinal Muller cells. Photoelectric dye may be a candidate agent for neuroprotection in retinitis pigmentosa and other retinal diseases.

DOI： 10.1089/jop.2016.0093

Size control of aromatic polyamide hollow spheres prepared by reaction-induced phase separation Reviewed

Hirofumi Nakayama, Naoto Adachi, Hironori Atarashi, Tetsuya Uchida, Shinichi Yamazaki, Kunio Kimura

POLYMER 111 239 - 243 2017.2

Language：English Publishing type：Research paper (scientific journal) Publisher：ELSEVIER SCI LTD

Size control of the poly (1,4-phenylene-5-hydroxyisophthalamide) hollow spheres was examined by tuning the polymerization condition, focusing on concentration, temperature and solvent. Higher concentration lowered the diameter owing to the higher degree of super-saturation for nucleation. Temperature drop during the polymerization just before the nucleation was so effective to make the diameter smaller. Moreover, the diameter was susceptive to the solubility of oligomers in the solvent, and higher content of liquid paraffin in the aromatic solvent lowered the solubility, resulting in the decrease in the diameter. Based on these results, the combination of the temperature drop and the solvent effect was the most desirable to prepare the smallest hollow spheres, and the diameter of hollow spheres could be controlled from 4.4 to 0.7 mu m. (C) 2017 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.polymer.2017.01.060

Subretinal implantation of Okayama University-type retinal prosthesis (OUReP (TM)) in canine eyes by vitrectomy Reviewed

Toshihiko Matsuo, Tetsuya Uchida, Makoto Nitta, Koichiro Yamashita, Shigiko Takei, Daisuke Ido, Mamoru Tanaka, Masao Oguchi, Toshinori Furukawa

JOURNAL OF VETERINARY MEDICAL SCIENCE 79 ( 12 ) 1939 - 1946 2017

Language：English Publishing type：Research paper (scientific journal) Publisher：JAPAN SOC VET SCI

Okayama University-type retinal prosthesis (OUReP (TM)) is a photoelectric dye-coupled polyethylene film which generates electric potential in response to light and stimulates nearby neurons. This study aims to test surgical feasibility of subretinal implantation and functional durability of dye-coupled films in the subretinal space. The dye-coupled films were implanted subretinally by 25-gauge vitrectomy in the right eye of 11 normal beagle dogs: 2 dogs served for film removal after 5-month film implantation, 3 dogs for film removal after 3-month film implantation, 3 dogs for 3-month film implantation and pathological examination, and 3 dogs for sham surgery. The surface electric potential of the removed dye-coupled films in response to light was measured by the Kelvin Probe system. At surgery, rolled-up dye-coupled films in 5 x 5 mm square size could be inserted into subretinal space of retinal detachment induced by fluid injection with a 38-gauge polyimide tip. Retinal attachment was maintained by silicone oil injection in vitreous cavity. At autopsy, the retina in all dogs maintained the ganglion cell layer, inner and outer nuclear layers while it lost the outer segments in some part. All 5 sheets of removed dye-coupled films maintained the dye color. One sheet of the 5-month implanted film showed proportional increase of surface potential in response to increasing light intensity. Subretinal implantation of OUReP (TM) by vitrectomy was technically feasible in canine eyes, and OUReP (TM) maintained the function of generating light-evoked surface potential after 5 months in subretinal implantation.

DOI： 10.1292/jvms.17-0450

Preparation of cellulose nanofibers coated with poly(vinyl alcohol) crystals and their application in composite films Reviewed

Tetsuya Uchida, Fumiaki Iwaguro, Risa Yanai, Haruka Dodo

RSC ADVANCES 7 ( 32 ) 19828 - 19832 2017

Authorship：Lead author,　Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：ROYAL SOC CHEMISTRY

Poly(vinyl alcohol) (PVA) was crystallized from a dilute solution in the presence of cellulose nanofibers (CeNFs). The CeNFs acted as nucleating agents for PVA crystallization, and PVA crystals were grown on the CeNFs' surface. As a result, CeNFs coated with PVA crystals (CeNF/PVA nanocomposite fiber (NCF(CeNF/PVA))) were successfully obtained. The NCF(CeNF/PVA) showed good dispersibility in water even after drying. Composite films were prepared using the aforementioned NCF(CeNF/PVA) and their mechanical properties were measured. Despite the low content of NCF(CeNF/PVA=1/5) (0.1 wt%, corresponding to 1.7 x 10(-2) wt% CeNF), the mechanical properties of the composite films improved in comparison to those of the control samples. This reinforcement effect of the NCF(CeNF/PVA=1/5) was greater than that of pure CeNFs. Surface modification of the NCF was also discussed, and the surface hydrophilicity of the NCF could be controlled depending on the choice of coating crystal.

DOI： 10.1039/c7ra01062a

Crystallization from Dilute Solution of Poly(p-Phenylene Benzobisthiazole) (PBZT) in the Presence of Carbon Nanotubes Reviewed

Tetsuya Uchida, Atsushi Mishima, Takayuki Ikeda, Masashi Furukawa, Koji Asanuma

JOURNAL OF FIBER SCIENCE AND TECHNOLOGY 73 ( 1 ) 1 - 7 2017

Authorship：Lead author,　Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：SOC FIBER SCIENCE TECHNOLOGY

Poly(p-phenylene benzobisthiazole) (PBZT) Was crystallized from dilute solution in the presence of single-wall carbon nanotube (SWNT) or multi-wall carbon nanotube (MWNT). In this crystallisation condition, SWNT existed as pristine bundles. SWNT bundles and MWNT acted as nucleating agents of PBZT crystallisation.The nucleating effect of the SWNT bundle was larger than that of MWNT. Transmission electron microscope observation revealed that the morphology of the PBZT crystal on the carbon nanotube (CNT) could be controlled by crystallization condition such as molecular length of PBZT, H2SO4 concentration, variety of CNT. Thermal stability of PBZT crystallized on SWNT bundles was discussed by the observation of crystal dissolution temperature.

DOI： 10.2115/fiberst.2017-0001

Apoptosis reduction by a photoelectric dye used for Okayama University-type retinal prosthesis (OUReP (TM)) Reviewed

Shihui Liu, Toshihiko Matsuo, Osamu Hosoya, Tetsuya Uchida

INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE 57 ( 12 ) 2016.9

Preparation of helical crystals of aromatic poly(ester-imide) and on-off switching of helix formation Reviewed

Takuya Ohnishi, Miki Nakagawa, Kanji Wakabayashi, Tetsuya Uchida, Shinichi Yamazaki, Kunio Kimura

POLYMER 98 378 - 386 2016.8

Language：English Publishing type：Research paper (scientific journal) Publisher：ELSEVIER SCI LTD

Preparation of poly[4-(5-oxy-1,3-dioxoisoindoline-2-yl)benzoyl] (PODB) crystals, which was an intractable aromatic poly(ester-imide), was examined by means of reaction-induced crystallization of oligomers during the polymerization. Highly crystalline PODB helical ribbons were obtained by the polymerization of N-(4-carboxyphenyl)-4-acetoxyphthalimide in aromatic solvent at 280-330 degrees C at a concentration of 0.5-1.0%. The PODB molecules aligned along the long axis of the helical ribbon. The pitch of the helix increased with the polymerization temperature and it could be controlled from 320 nm to 1.3 mu m. Further, the fibrillar PODB crystals comprised of the helical and the non-helical blocks were prepared by the on-off switching of the helical morphology with the changing the temperature and the concentration of the polymerization. These results provided the methodology for the morphology control of polymer crystals. (C) 2016 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.polymer.2016.06.055

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