148 results on '"Tsuyoshi Ando"'
Search Results
2. Supplementary Methods from Vaccination with Antigen-Transfected, NKT Cell Ligand–Loaded, Human Cells Elicits Robust In Situ Immune Responses by Dendritic Cells
- Author
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Shin-ichiro Fujii, Ryozo Nagai, Tsuyoshi Ando, Hisashi Koike, Kara Bickham, Niels Schaft, Jan Dorrie, Kenichi Hanada, Keigo Nishida, Hirokazu Matsushita, Yusuke Sato, Hidetoshi Sugahara, Tomoji Maeda, Kenichi Masuda, Yasuyuki Ishii, Kazuhiro Kakimi, Miki Asakura, Jun Shinga, Takuya Mizuno, and Kanako Shimizu
- Abstract
PDF file - 118K
- Published
- 2023
3. RAFT Polymerization of N-Methyl-N-vinylacetamide and Related Double Hydrophilic Block Copolymers
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Alexis Dupre--Demorsy, Olivier Coutelier, Mathias Destarac, Clémence Nadal, Valérie Bourdon, Tsuyoshi Ando, Hiroharu Ajiro, Interactions moléculaires et réactivité chimique et photochimique (IMRCP), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Fédération de Recherche Fluides, Energie, Réacteurs, Matériaux et Transferts (FERMAT), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), P3R - Polymères de Précision par Procédés Radicalaires (P3R), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie de Toulouse (ICT), Centre interuniversitaire de recherche et d'ingenierie des matériaux (CIRIMAT), Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)
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Inorganic Chemistry ,Polymers and Plastics ,Organic Chemistry ,Materials Chemistry ,[CHIM]Chemical Sciences - Abstract
International audience
- Published
- 2022
4. Tailor-made poly(vinylamine) via purple LED-activated RAFT polymerization of N-vinylformamide
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Izabela Kurowska, Alexis Dupre–Demorsy, Stéphane Balayssac, Marie Hennetier, Audrey Ric, Valérie Bourdon, Tsuyoshi Ando, Hiroharu Ajiro, Olivier Coutelier, Mathias Destarac, Interactions moléculaires et réactivité chimique et photochimique (IMRCP), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Fédération de Recherche Fluides, Energie, Réacteurs, Matériaux et Transferts (FERMAT), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), P3R - Polymères de Précision par Procédés Radicalaires (P3R), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie de Toulouse (ICT), BIBAC - Chimie analytique et interactions biomolécules - matière molle biomimétique (BIBAC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT), and Université Toulouse III - Paul Sabatier (UT3)
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Polymers and Plastics ,Organic Chemistry ,Materials Chemistry ,[CHIM]Chemical Sciences - Abstract
Photo-iniferter reversible addition-fragmentation chain transfer (PI-RAFT) of N-vinylformamide (NVF) was demonstrated by using purple light. PNVFs with predetermined molar masses and narrow molar mass distributions were obtained. High RAFT chain-end fidelity was confirmed by MALDI-TOF and ESI-MS, and chain extension experiment. To demonstrate the potential of this approach, an original PVP-b-PNVF diblock copolymer was synthesized and characterized by aqueous SEC, A4F, and
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- 2022
5. Radical copolymerization on fluoroalkyl α-chloroacrylate monomers for copolymer composition control
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Ikuo Yamamoto, Tsuyoshi Ando, Hiroharu Ajiro, and Minami Shinichi
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Acrylate ,Polymers and Plastics ,Chemistry ,Substituent ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,0104 chemical sciences ,Styrene ,chemistry.chemical_compound ,Monomer ,Polymerization ,Polymer chemistry ,Materials Chemistry ,Copolymer ,Side chain ,Reactivity (chemistry) ,0210 nano-technology - Abstract
The radical copolymerization on α-substituted fluoroalkyl acrylate (FA) monomer bearing C4, C6, and C8 as perfluoroalkyl (Rf) groups, as well as the variation of α-substituents, hydrogen, methyl, and chlorine with styrene was investigated. Q-e values and monomer reactivity ratio of FA monomers were estimated. When the alpha position of FA monomer of C6 as Rf group was changed from −H to −CH3, the e value decreased from 0.85 to 0.60. The substituent of −Cl resulted in an e value of 1.06. The Q values were also markedly changed. When the alpha position was changed from −H to −CH3, the Q value increased from 0.38 to 0.79. The substituent of −Cl resulted in a Q value of 2.90. The copolymer composition of α-substituted FA monomers with stearyl acrylate (C18A) was simulated. The obtained results revealed that a chlorine substituent at the alpha position emphasizes the polymerization which would contribute to a novel material design containing a fluorine side chain in a monomer structure.
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- 2021
6. Rajendra Bhatia and his mathematical achievements
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Fuad Kittaneh, Tsuyoshi Ando, Mohammad Sal Moslehian, Tanvi Jain, Ilya M. Spitkovsky, and Chandler Davis
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Algebra ,Algebra and Number Theory ,Linear algebra ,Biography ,Matrix analysis ,Operator theory ,Analysis ,Mathematics - Abstract
In this paper, we provide a biography of Professor Rajendra Bhatia and discuss some of his influential mathematical works as one of the leading researchers in matrix analysis and linear algebra.
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- 2020
7. Synthesis of spiropyran with methacrylate at the benzopyran moiety and control of the water repellency and cell adhesion of its polymer film
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Hiroharu Ajiro, Murase Nobuo, and Tsuyoshi Ando
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Indoles ,Polymers ,Surface Properties ,Radical polymerization ,Biomedical Engineering ,Photochemistry ,Nitrobenzene ,Mice ,chemistry.chemical_compound ,Cell Adhesion ,Animals ,Benzopyrans ,General Materials Science ,Merocyanine ,Particle Size ,Cells, Cultured ,chemistry.chemical_classification ,Spiropyran ,Molecular Structure ,General Chemistry ,General Medicine ,Polymer ,Nitro Compounds ,Solvent ,chemistry ,Polymerization ,Positron-Emission Tomography ,NIH 3T3 Cells ,Methacrylates ,Protic solvent - Abstract
Stimuli-responsive materials have been actively researched over the past few decades. Among such materials, spiropyran is one of the most attractive compounds because the structure and polarity of the material are dramatically changed after photo irradiation, unlike other materials. In this work, we designed and synthesized a spiropyran derivative (SpMA) with a methacryloyl group on the nitrobenzene ring of a spiropyran skeleton. The UV spectra of the newly synthesized SpMA showed the photo-isomerization of spiropyran. The maximum absorption wavelength (λmax) of SpMA was 616 nm in n-hexane, a nonpolar solvent, although λmax of SpMA was 532 nm in methanol, a polar protic solvent, which resulted in an 84 nm blue-shift. SpMA was successfully polymerized by ruthenium (Ru)-catalyzed living radical polymerization. Poly(SpMA) (PSpMA) was then spin-coated on a PET substrate in order to control the surface properties of water repellency and cell adhesion. The water repellency was decreased approximately 10° under UV irradiation, because of the polarity change of PSpMA caused by photo-isomerization from the spiropyran (SP) type to the merocyanine (MC) type. In addition, NIH3T3 cells were spread only on 6% of the surface of the PSpMA thin film after UV irradiation compared with no UV irradiation. The polarity change of PSpMA by photo-isomerization is also believed to be the reason for this behavior. As a result, we successfully synthesized a photo-controllable cell culture scaffold.
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- 2020
8. Composition Regulation by Flow Copolymerization of Methyl Methacrylate and Glycidyl Methacrylate with Free Radical Method
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Araki Wakiuchi, Shogo Takasuka, Shigehito Asano, Ryo Hashizume, Aniruddha Nag, Miho Hatanaka, Tomoyuki Miyao, Yuya Ohnishi, Takamitsu Matsubara, Tsuyoshi Ando, Tetsunori Sugawara, Mikiya Fujii, and Hiroharu Ajiro
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Polymers and Plastics ,General Chemical Engineering ,Organic Chemistry ,Materials Chemistry - Published
- 2023
9. Comparative Study of Pharmacopoeias in Japan, Europe, and the United States: Toward the Further Convergence of International Pharmacopoeial Standards
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Yujiro Kameyama, Maki Matsuhama, Tsuyoshi Ando, Rieko Saito, Chie Mizumaru, and Seiko Miyazaki
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Drug supply ,medicine.medical_specialty ,business.industry ,Chemistry ,Chemistry, Pharmaceutical ,Public health ,Accounting ,Convergence (economics) ,Context (language use) ,General Chemistry ,General Medicine ,United States ,Drug market ,law.invention ,Europe ,Japanese Pharmacopoeia ,Japan ,law ,Drug Discovery ,medicine ,Humans ,Pharmacopoeia ,Formulary ,business - Abstract
A pharmacopoeia's core mission is to protect public health by creating and making available public standards to help ensure the quality of drugs. In recent years, pharmacopoeias around the world have harmonized their standards in the present context of globalized drug supply chains and markets. For example, the Pharmacopoeial Discussion Group has worked to harmonize excipient monographs and general chapters. In addition, the International Meeting of World Pharmacopoeias has been held by the WHO to discuss information exchange and international collaboration, among other topics. To contribute further to the protection of public health in the globalized drug market, we conducted a comparative study of the pharmacopoeias in Japan, Europe, and the United States. We aimed to examine current differences among the Japanese Pharmacopoeia, the European Pharmacopoeia, and the United States Pharmacopeia-National Formulary and to identify areas that require further collaboration among the three pharmacopoeias. In this study, we analyzed monographs and general chapters listed in the three pharmacopoeias. We identified the features of the monographs and general chapters listed in each pharmacopoeia, as well as differences across the pharmacopoeias. Moreover, on the basis of our findings, we suggest standards that require further collaboration among the pharmacopoeias in certain preferred areas. The comparison data produced by this study are expected to be used to develop strategies for future revisions of pharmacopoeias around the world.
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- 2019
10. Water Repellency of Bottlebrush Polymers Consisting of Monomer Units with a Long Alkyl Chain Synthesized by Ru-Catalyzed Living Radical Polymerization
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Takuma Kawabe, Shibutani Shota, Tsuyoshi Ando, Yoshito Tanaka, Kayo Terada, and Murase Nobuo
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chemistry.chemical_classification ,chemistry.chemical_compound ,Monomer ,Polymers and Plastics ,chemistry ,Chain (algebraic topology) ,Process Chemistry and Technology ,Organic Chemistry ,Radical polymerization ,Polymer chemistry ,Polymer ,Alkyl ,Catalysis - Abstract
Over the past few decades, techniques for improving the surface properties of various materials have been actively researched. In particular, water repellency is an important factor for controlling...
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- 2019
11. Optical control of cell differentiation on synthetic collagen-like scaffolds
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Masao Tanihara, Ryosuke Honda, Tsuyoshi Ando, and Mime Kobayashi
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Cellular differentiation ,0206 medical engineering ,Biomedical Engineering ,Biophysics ,Biocompatible Materials ,Bioengineering ,02 engineering and technology ,Biomaterials ,Tissue engineering ,Animals ,Cells, Cultured ,Tissue Engineering ,Tissue Scaffolds ,Chemistry ,Stem Cells ,Cell Differentiation ,021001 nanoscience & nanotechnology ,Biocompatible material ,020601 biomedical engineering ,Rats ,Cell biology ,Optical control ,Cell Fate Control ,Collagen ,Stem cell ,0210 nano-technology - Abstract
We have developed biocompatible scaffolds that enable cell fate control with visible light. The scaffolds are based on synthetic collagen-like polypeptide, poly(prolyl-hydroxyprolyl-glycyl) {poly(Pro-Hyp-Gly)} which has been used for cosmetics and other healthcare applications. Bioactive peptides were conjugated to the scaffolds via photoactivation reaction utilizing 488 nm visible light. In addition, the use of a photocleavable crosslinker enables dissociation of chemical moieties by 405 nm laser irradiation. The synthesis scheme enables optical control to attach and detach functional peptides in pre-patterned shapes. Using bone forming peptide (BFP), we demonstrate that calcium deposition by rat bone stromal cells can be directed on the scaffold. Using other signaling molecules and three-dimensional scaffolds, controlled differentiation of stem cells can be achieved by spatio-temporally specific irradiation of confocal microscope laser.
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- 2019
12. [Implementation of the Latest Scientific Knowledge/Technologies and Activities for International Harmonisation of the Japanese Pharmacopoeia]
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Tomoko Osawa and Tsuyoshi Ando
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Pharmacology ,Pharmacopoeias as Topic ,Quality Control ,Sociology of scientific knowledge ,Medical treatment ,business.industry ,media_common.quotation_subject ,International Cooperation ,Pharmaceutical Science ,law.invention ,Biopharmaceutics ,Product (business) ,Engineering management ,Japanese Pharmacopoeia ,Knowledge ,Japan ,law ,Health care ,Standard test ,Humans ,Quality (business) ,Business ,Pharmacopoeia ,media_common - Abstract
The Japanese Pharmacopoeia (JP) is an official document that defines the specifications, criteria, and standard test methods necessary to properly ensure the quality of medicines in Japan. To ensure the efficacy and safety of pharmaceutical products, it is essential to establish standards that ensure their quality. For this purpose, the JP aims to include all drugs that are important from the viewpoint of healthcare and medical treatment, and description of each monograph of medicine is maintained and improved so that those standards can be generally practiced. In addition, to play a key role as the official document in the field of pharmaceutical product quality, JP contents are enhanced by proactively introducing the latest scientific knowledge and technologies. As the international manufacturing of pharmaceutical products and their raw materials that are distributed in Japan is increasing, the JP has recently begun to promote the international harmonisation of pharmaceutical excipients and general tests through the Pharmacopoeial Discussion Group (PDG) and to swiftly implement the harmonised items in the JP. In addition, the JP will implement internationally harmonised concepts and specifications for pharmaceutical products, e.g., the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH), to define the latest concepts of quality control for pharmaceutical products in the official document. We introduce the implementation of the latest scientific knowledge, technologies, and activities for international harmonisation of the JP.
- Published
- 2020
13. Norm Ratios Under a Weak Order Relation in M m ⊗ M n ${\mathbb {M}}_{m}\otimes {\mathbb {M}}_{n}$
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Tsuyoshi Ando
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Combinatorics ,Physics ,symbols.namesake ,Tensor product ,General Mathematics ,Trace norm ,Norm (mathematics) ,Hilbert space ,symbols ,Mathematics::Representation Theory ,Operator norm - Abstract
In the real Hilbert space of self-adjoint elements of the tensor product ${\mathbb {M}}_{m}\otimes {\mathbb {M}}_{n}$ , there are two natural cones besides the cone ${\mathfrak {P}}_{0}$ of positive semi-definite elements. The one is and the other is the cone ${\mathfrak {P}}_{-}$ , dual to ${\mathfrak {P}}_{+}$ with respect to the inner product. Then, ${\mathfrak {P}}_{+} \subset {\mathfrak {P}}_{0} \subset {\mathfrak {P}}_{-}.$ A weak order relation ≽ is introduced by Our interest is in finding bounds for the ratio | | |T| | |/| | |S| | | for S ≽T ≽ 0, where | | |⋅| | | is one of the operator norm, the trace norm, and the Hilbert-Schmidt norm.
- Published
- 2018
14. Severe Fever with Thrombocytopenia Syndrome in Cats and Its Prevalence among Veterinarian Staff Members in Nagasaki, Japan
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Kouichi Morita, Shingo Inoue, Shintaro Kurihara, Takeshi Nabeshima, Daisuke Hayasaka, Mya Myat Ngwe Tun, Miho Obata, Tsuyoshi Ando, Hiroshi Shimoda, Weiyin Hu, and Koichi Izumikawa
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Phlebovirus ,0301 basic medicine ,Severe Fever with Thrombocytopenia Syndrome ,030106 microbiology ,Genome, Viral ,Antibodies, Viral ,Cat Diseases ,Microbiology ,Article ,Virus ,Veterinarians ,03 medical and health sciences ,Japan ,Virology ,Genotype ,Animals ,Medicine ,Seroprevalence ,Sentinel Animals ,Phylogeny ,CATS ,biology ,business.industry ,High-Throughput Nucleotide Sequencing ,medicine.disease ,QR1-502 ,Severe fever with thrombocytopenia syndrome ,030104 developmental biology ,Infectious Diseases ,Immunoglobulin G ,Cats ,biology.protein ,RNA, Viral ,Antibody ,business - Abstract
In this study, we investigated severe fever with thrombocytopenia syndrome (SFTS) virus (SFTSV) infection in cats in Nagasaki, Japan. In total, 44 of 133 (33.1%) cats with suspected SFTS were confirmed to be infected with SFTSV. Phylogenetic analyses of SFTSV isolates from cats indicated that the main genotype in Nagasaki was J1 and that unique reassortant strains with J2 (S segment) and unclassified genotypes (M and L segments) were also present. There were no significant differences in virus growth in cell cultures or fatality in SFTSV-infected mice between the SFTSV strains that were isolated from recovered and fatal cat cases. Remarkably, SFTSV RNAs were detected in the swabs from cats, indicating that the body fluids contain SFTSV. To evaluate the risk of SFTSV infection when providing animal care, we further examined the seroprevalence of SFTSV infection in veterinarian staff members, 3 of 71 (4.2%) were seropositive for SFTSV-specific antibodies. Our results provide useful information on the possibility of using cats as sentinel animals and raised concerns of the zoonotic risk of catching SFTSV from animals.
- Published
- 2021
15. Unusual, neurological and severe dengue manifestations during the outbreak in Sri Lanka, 2017
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Shanthi Attanayake, Rohitha Muthugala, Aung Min Soe, Shingo Inoue, Takeshi Nabeshima, Dulani Jayawardana, Corazon C. Buerano, Mya Myat Ngwe Tun, Tsuyoshi Ando, Daisuke Hayasaka, Kouichi Morita, Shyam Prakash Dumre, and Lakmali Rajamanthri
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0301 basic medicine ,Adult ,Male ,Pediatrics ,medicine.medical_specialty ,Myocarditis ,Adolescent ,Genotype ,viruses ,Secondary infection ,030106 microbiology ,Antibodies, Viral ,Serology ,Dengue fever ,Disease Outbreaks ,Dengue ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Virology ,parasitic diseases ,medicine ,Humans ,030212 general & internal medicine ,Severe Dengue ,Child ,Phylogeny ,Aged ,Sri Lanka ,Molecular epidemiology ,business.industry ,Coinfection ,virus diseases ,Outbreak ,Infant ,biochemical phenomena, metabolism, and nutrition ,Dengue Virus ,Middle Aged ,medicine.disease ,Infectious Diseases ,Immunoglobulin M ,Child, Preschool ,Population study ,RNA, Viral ,Female ,Nervous System Diseases ,business ,geographic locations ,Encephalitis - Abstract
Background Sri Lanka experienced its largest dengue outbreak in 2017 with more than 185,000 dengue cases including at least 250 fatalities. Objectives Our study aimed to characterize the clinical, immunological and virological features of confirmed dengue patients in Sri Lanka during the outbreak in 2017 when unusual manifestations of severe dengue were observed. Study design Sera from 295 patients who were admitted to Teaching Hospital Kandy, Kandy, Sri Lanka between March 2017- January 2018 were subjected to NS1 antigen, IgM and IgG ELISAs, virus isolation, conventional and real time RT-PCR and next generation sequencing. Results Primary and secondary infections were detected in 48.5 % and 51.5 % of the study population, respectively. Two hundred twenty five DENV strains were isolated (219 DENV-2, one DENV-3, two DENV-4, two mixed infections of DENV-2 and -3 and one mixed infection of DENV-2 and -4). Unusual and severe manifestations such as encephalitis, encephalopathy, liver failure, kidney failure, myocarditis, Guillain–Barre syndrome and multi-organ failure were noted in 44 dengue patients with 11 deaths. The viraemia levels in patients with primary infection and unusual manifestations were significantly higher compared to those in patients with secondary infection. A new clade of DENV-2 Cosmopolitan genotype strains was observed with the strains closely related to those from China, Malaysia, Indonesia, Singapore and Taiwan. Conclusions The new clade of DENV-2 cosmopolitan genotype observed in Sri Lanka in 2017 caused an unprecedented, severe dengue outbreak. The emergence of DENV-3 and DENV-4 in the 2017 outbreak might cause future outbreaks in Sri Lanka.
- Published
- 2019
16. Japanese Encephalitis- and Dengue-Associated Acute Encephalitis Syndrome Cases in Myanmar
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Tsuyoshi Ando, Chang-Kweng Lim, Mya Myat Ngwe Tun, Hlaing Myat Thu, Daisuke Hayasaka, Kyaw Zin Thant, Aung Kyaw Kyaw, Shingo Inoue, Takeshi Nabeshima, Masayuki Saijo, Kouichi Morita, and Corazon C. Buerano
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Male ,viruses ,030231 tropical medicine ,Enzyme-Linked Immunosorbent Assay ,Myanmar ,Dengue virus ,medicine.disease_cause ,Antibodies, Viral ,Virus ,Dengue fever ,Serology ,Dengue ,03 medical and health sciences ,0302 clinical medicine ,Neutralization Tests ,Virology ,medicine ,Humans ,Child ,Encephalitis, Japanese ,Phylogeny ,biology ,business.industry ,Antibody titer ,Infant ,Articles ,Japanese encephalitis ,Dengue Virus ,medicine.disease ,biology.organism_classification ,Flavivirus ,Infectious Diseases ,Child, Preschool ,Parasitology ,Female ,business ,Encephalitis - Abstract
This study was conducted to find the burden of dengue virus (DENV) and Japanese encephalitis virus (JEV) among children under the age of 13, who presented with acute encephalitis syndrome at Mandalay Children Hospital in Myanmar in 2013. Molecular and serological investigations were performed on 123 cerebrospinal fluid (CSF) samples collected from these patients. By neutralization tests and/or virus isolation, four (3.3%) JEV- and one DENV-associated encephalitis cases (0.8%) were confirmed. Antibody titer against JEV Genotype 3 was the highest among the laboratory-confirmed JEV cases. One strain of DENV-1 with Genotype 1 was isolated from the CSF sample of the dengue encephalitis patient; this was similar to the virus circulating in the study area and neighboring countries. This study shows that flaviviruses are important pathogens causing encephalitis in Myanmar. Active disease surveillance, vector control,and vaccination programs should be enforced to reduce the morbidity and mortality caused by flavivirus encephalitis., The American journal of tropical medicine and hygiene, 100(3), pp.643-646; 2019
- Published
- 2019
17. Norm Conditions for Separability in $${\mathbb M}_m\otimes {\mathbb M}_n$$
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Tsuyoshi Ando
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Combinatorics ,Tensor product ,Norm (mathematics) ,Separable space ,Mathematics - Abstract
An element \(\mathbf{S}\) of the tensor product \({\mathbb M}_m\otimes {\mathbb M}_n\) is said to be separable if it admits a (separable) decomposition $$ \mathbf{S}\ =\ \sum _pX_p\otimes Y_p \quad \exists \ \ 0 \le X_p \in {\mathbb M}_m,\ \exists \ 0 \le Y_p \in {\mathbb M}_n. $$ This decomposition is not unique. We present some conditions on suitable norms of \(\mathbf{S}\) which guarantee its separability. Even when separability of \(\mathbf{S}\) is guaranteed by some method, its separable decomposition itself is difficult to construct. We present a general condition which makes it possible to find a way of an explicit separable decomposition.
- Published
- 2019
18. Efficacy on the risk of vertebral fracture with administration of once-weekly 17.5 mg risedronate in Japanese patients of established osteoporosis with prevalent vertebral fractures: a 156-week longitudinal observational study in daily practice
- Author
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Mitsuharu Osawa, Toshitaka Nakamura, Kyoko Takeda, Masahiko Nishikawa, Yoshinori Ikeda, Ryoichi Muraoka, Tsuyoshi Ando, Toshiaki Kamisaki, Takashi Umemura, and Satoshi Soen
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Male ,medicine.medical_specialty ,Bone density ,Endocrinology, Diabetes and Metabolism ,Osteoporosis ,030209 endocrinology & metabolism ,Lumbar vertebrae ,Collagen Type I ,Drug Administration Schedule ,03 medical and health sciences ,0302 clinical medicine ,Endocrinology ,Asian People ,Japan ,Bone Density ,Risk Factors ,Prevalence ,medicine ,Humans ,Orthopedics and Sports Medicine ,Longitudinal Studies ,Prospective Studies ,030212 general & internal medicine ,Prospective cohort study ,Aged ,Lumbar Vertebrae ,Bone Density Conservation Agents ,Hip Fractures ,business.industry ,Incidence ,Incidence (epidemiology) ,General Medicine ,medicine.disease ,Surgery ,Risedronate Sodium ,medicine.anatomical_structure ,Relative risk ,Orthopedic surgery ,Patient Compliance ,Spinal Fractures ,Female ,Peptides ,business ,Risedronic Acid - Abstract
Currently, the only available evidence for the efficacy of once-weekly 17.5 mg risedronate in preventing vertebral fractures was obtained in a 48-week study in Japan. We performed a 156-week prospective, longitudinal, observational study to determine the efficacy of the 17.5 mg risedronate in preventing vertebral fractures. We included Japanese patients with established osteoporosis who were older than 50 years and had radiographically confirmed vertebral fractures. The primary endpoint was the incidence of vertebral fractures every 24 weeks, with the final interval spanning 36 weeks. We also calculated the change in bone mineral density of the lumbar spine (L2-4 BMD) and urinary N-telopeptide of type I collagen (u-NTX), and assessed the incidence of adverse drug reactions and the drug adherence rate. Data from 241 patients were available for analysis of vertebral fracture prevention. The incidence rate of vertebral fractures decreased in a time-dependent manner (P = 0.0006; Poisson regression analysis). The risk ratio (fracture incidence per 100 person-years in the final 36 weeks versus that in the first 24 weeks) was 0.21 (95 % confidence interval 0.08-0.55). Compared to baseline values, L2-4 BMD increased by 6.41 % at 156 weeks, while u-NTX decreased by 36 % at 24 weeks and was maintained thereafter (P
- Published
- 2016
19. Geometric mean and norm Schwarz inequality
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Tsuyoshi Ando
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Hölder's inequality ,Kantorovich inequality ,Pure mathematics ,Control and Optimization ,Ky Fan inequality ,010103 numerical & computational mathematics ,Inequality of arithmetic and geometric means ,01 natural sciences ,47A63 ,47A64 ,0101 mathematics ,Cauchy–Schwarz inequality ,Computer Science::Databases ,Mathematics ,norm Schwarz inequality ,Algebra and Number Theory ,010102 general mathematics ,Mathematical analysis ,normal operator ,geometric mean ,47A30 ,norm inequality ,Schatten norm ,Rearrangement inequality ,Operator norm ,47B15 ,Analysis - Abstract
Positivity of a $2\times2$ operator matrix $[\begin{smallmatrix}A&B\\B^{*}&C\end{smallmatrix}]\geq0$ implies $\sqrt{\|A\|\cdot\|C\|}\geq\|B\|$ for operator norm $\|\cdot\|$ . This can be considered as an operator version of the Schwarz inequality. In this situation, for $A,C\geq0$ , there is a natural notion of geometric mean $A\sharp C$ , for which $\sqrt{\|A\|\cdot\|C\|}\geq\|A\sharp C\|$ . In this paper, we study under what conditions on $A$ , $B$ , and $C$ or on $B$ alone the norm inequality $\sqrt{\|A\|\cdot\|C\|}\geq\|B\|$ can be improved as $\|A\sharp C\|\geq\|B\|$ .
- Published
- 2016
20. Proof of a conjectured lower bound on the chromatic number of a graph
- Author
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Tsuyoshi Ando and Minghua Lin
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Discrete mathematics ,Combinatorics ,Numerical Analysis ,Mathematics::Combinatorics ,Algebra and Number Theory ,Conjecture ,Discrete Mathematics and Combinatorics ,Bound graph ,Geometry and Topology ,Chromatic scale ,Upper and lower bounds ,Graph ,Mathematics - Abstract
We confirm a conjecture in Wocjan and Elphick (2013) [4] about a lower bound of the chromatic number of a graph.
- Published
- 2015
21. Encapsulation of rat bone marrow stromal cells using a poly-ion complex gel of chitosan and succinylated poly(Pro-Hyp-Gly)
- Author
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Mime Kobayashi, Shiho Hirohara, Yoshiaki Shibasaki, Tsuyoshi Ando, Kayo Terada, Yuni Kusumastuti, and Masao Tanihara
- Subjects
Stromal cell ,Sodium ,0206 medical engineering ,technology, industry, and agriculture ,Biomedical Engineering ,Cationic polymerization ,Medicine (miscellaneous) ,chemistry.chemical_element ,02 engineering and technology ,021001 nanoscience & nanotechnology ,020601 biomedical engineering ,Biomaterials ,Chitosan ,chemistry.chemical_compound ,chemistry ,Self-healing hydrogels ,medicine ,Viability assay ,Swelling ,medicine.symptom ,0210 nano-technology ,Cell encapsulation ,Biomedical engineering ,Nuclear chemistry - Abstract
Encapsulation of stem cells into a three-dimensional (3D) scaffold is necessary to achieve tissue regeneration. Prefabricated 3D scaffolds, such as fibres or porous sponges, have limitations regarding homogeneous cell distribution. Hydrogels that can encapsulate cells such as animal-derived collagen gels need adjustment of the pH and/or temperature upon cell mixing. In this report, we fabricated a poly-ion complex (PIC) hydrogel of chitosan and succinylated poly(Pro-Hyp-Gly) and assessed its effect on cell viability after encapsulation of rat bone marrow stromal cells. PIC hydrogels were obtained successfully with a concentration of each precursor as low as 3.0-3.8 mg/ml. The maximum gelation and swelling ratios were achieved with an equal molar ratio (1:1) of anionic and cationic groups. Using chitosan acetate as a cationic precursor produced a PIC hydrogel with both a significantly greater gelation ratio and a better swelling ratio than chitosan chloride. Ammonium succinylated poly(Pro-Hyp-Gly) as an anionic precursor gave similar gelation and swelling ratios to those of sodium succinylated poly(Pro-Hyp-Gly). Cell encapsulation was also achieved successfully by mixing rat bone marrow stromal cells with the PIC hydrogel simultaneously during its formation. The PIC hydrogel was maintained in the culture medium for 7 days at 37°C and the encapsulated cells survived and proliferated in it. Although it is necessary to improve its functionality, this PIC hydrogel has the potential to act as a 3D scaffold for cell encapsulation and tissue regeneration. Copyright © 2015 John Wiley & Sons, Ltd.
- Published
- 2015
22. Star Polymers for Biomedical Applications
- Author
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Tsuyoshi Ando
- Subjects
Materials science ,Polymers and Plastics ,Star polymer ,Materials Science (miscellaneous) ,Antifouling coating ,Chemical Engineering (miscellaneous) ,Organic chemistry ,Nanotechnology ,General Environmental Science - Published
- 2015
23. Isolation and genomic characterization of Culex flaviviruses from mosquitoes in Myanmar
- Author
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Yi Yi Mya, Kyaw Zin Thant, Daisuke Hayasaka, Miako Sakaguchi, Aung Kyaw Kyaw, Tsuyoshi Ando, Hlaing Myat Thu, Kouichi Morita, Mya Myat Ngwe Tun, Shingo Inoue, Takeshi Nabeshima, and Corazon C. Buerano
- Subjects
0301 basic medicine ,Cancer Research ,Culex ,viruses ,Virus isolation ,Genome, Viral ,Mosquito Vectors ,Myanmar ,Virus Replication ,Genome ,Host Specificity ,03 medical and health sciences ,Open Reading Frames ,Virology ,parasitic diseases ,Animals ,Humans ,Phylogeny ,Mosquito cell ,biology ,Flavivirus ,fungi ,virus diseases ,biochemical phenomena, metabolism, and nutrition ,biology.organism_classification ,Isolation (microbiology) ,Viral Tropism ,030104 developmental biology ,Infectious Diseases ,Epidemiological Monitoring ,Wang Thong virus ,Culex flavivirus - Abstract
An entomological surveillance of arboviruses was conducted in Myanmar in 2014. A total of 8357 Culex mosquito vectors were collected in the Mandalay area and virus isolation was done by using the mosquito cell line C6/36 E2. A total of eighteen strains of Culex flavivirus (CxFV) were isolated from Cx. tritaeniorhynchus, Cx. vishnui and Cx. fuscocephala. Like other insect-specific flaviviruses, CxFV can replicate only in mosquito cells but not in mammalian cells. These CxFV strains that were isolated in Japan from mosquitoes collected in Myanmar were closely related to the Wang Thong virus detected from Cx fusocephalus in Thailand and Cx.theileri flavivirus (CTFV) isolated from Cx. theileri mosquitoes in Portugal and Turkey. They encode a single open reading frame with 3357 amino acid residues. They have the characteristics of flaviviruses and have 95.62% amino acid identity with CTFV. This is the first report of CxFV in Myanmar with the characterized viral genome. This study illustrated that CxFV was circulating among the vectors of human pathogenic arboviruses in Myanmar but the impact of CxFV on other flaviviruses which are endemic in the study area still remains to be explored.
- Published
- 2017
24. Cytocompatible polyion complex gel of poly(Pro-Hyp-Gly) for simultaneous rat bone marrow stromal cell encapsulation
- Author
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Kayo Terada, Tsuyoshi Ando, Masao Tanihara, Farah Nurlidar, and Mime Kobayashi
- Subjects
0301 basic medicine ,Scaffold ,Materials science ,Stromal cell ,Cell Survival ,3D scaffold ,Cell ,Biomedical Engineering ,Biophysics ,Bioengineering ,Biocompatible Materials ,Capsules ,02 engineering and technology ,macromolecular substances ,poly(Pro-Hyp-Gly) ,Cell morphology ,complex mixtures ,Biomaterials ,03 medical and health sciences ,Tissue culture ,In vivo ,polyion complex gel ,Polymer chemistry ,medicine ,Animals ,simultaneous cell encapsulation ,Mesenchymal stem cell ,technology, industry, and agriculture ,Mesenchymal Stem Cells ,rat bone marrow stromal cells ,021001 nanoscience & nanotechnology ,Rats ,Molecular Weight ,030104 developmental biology ,medicine.anatomical_structure ,collagen-like polypeptide ,Protein Conformation, beta-Strand ,cytocompatible ,Collagen ,Stem cell ,0210 nano-technology ,Gels - Abstract
Polyion complex (PIC) gel of poly(Pro-Hyp-Gly) was successfully fabricated by simply mixing polyanion and polycation derivatives of poly(Pro-Hyp-Gly), a collagen-like polypeptide. The polyanion, succinylated poly(Pro-Hyp-Gly), and the polycation, arginylated poly(Pro-Hyp-Gly), contain carboxy (pKa = 5.2) and guanidinium (pKa = 12.4) groups, respectively. Mixing the polyanion and the polycation at physiological pH (pH = 7.4) resulted in PIC gel. The hydrogel formation was optimum at an equimolar ratio of carboxy to guanidinium groups, suggesting that ionic interaction is the main determinant for the hydrogel formation. The hydrogel was successfully used for simultaneous rat bone marrow stromal cell encapsulation. The encapsulated cells survived and proliferated within the hydrogel. In addition, the cells exhibited different morphology in the hydrogel compared with cells cultured on a tissue culture dish as a two-dimensional (2D) control. At day one, a round morphology and homogeneous single cell distribution were observed in the hydrogel. In contrast, the cells spread and formed a fibroblast-like morphology on the 2D control. After three days, the cells in the hydrogel maintained their morphology and some of them formed multicellular aggregates, which is similar to cell morphology in an in vivo microenvironment. These results suggest that the PIC gel of poly(Pro-Hyp-Gly) can serve as a cytocompatible three-dimensional scaffold for stem cell encapsulation, supporting their viability, proliferation, and in vivo-like behavior.
- Published
- 2017
- Full Text
- View/download PDF
25. Drug discovery in renal disease—towards a more efficient framework
- Author
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Kanako Watanabe, Tatsuo Kurokawa, Hisami Hiragi, Tsuyoshi Ando, Fumi Yamamoto, Masahiro Takeuchi, Charles van Ypersele de Strihou, Toshio Miyata, Douglas E. Vaughan, and Yoshiteru Oshima
- Subjects
Drug ,Drug Industry ,media_common.quotation_subject ,Disease ,Pharmacology ,Public-Private Sector Partnerships ,Rare Diseases ,Japan ,Renal Dialysis ,Drug Discovery ,Humans ,Medicine ,Developing Countries ,media_common ,International research ,Clinical Trials as Topic ,Government ,business.industry ,Drug discovery ,Drugs, Investigational ,Clinical trial ,Drug development ,Risk analysis (engineering) ,Nephrology ,Drug Design ,Investigational Drugs ,Kidney Failure, Chronic ,Kidney Diseases ,business ,Biomarkers - Abstract
The time and cost involved in bringing new drugs to the market hamper their approval. This problem is especially apparent in the case of renal diseases. Efficient drug research requires an a priori understanding of disease pathophysiology, target validation, rational and efficient drug discovery strategies and early testing of the physiological and pharmacological effects of the new agent in humans. Drug development initiated by academia benefits from international research networks and relies on internationally acceptable high-quality nonclinical data packages and bulk investigational drugs. Academics should, therefore, better understand pharmaceutical practice regulations and novel, efficient drug-development strategies. Many researchers remain unfamiliar with these areas and should collaborate with regulatory authorities to discover and validate surrogate markers for use in drug development, and to efficiently and effectively maximize the benefits and minimize the adverse effects of new drugs. The Japanese government and regulatory authorities have implemented a framework to encourage such collaborations; extension of this framework beyond its current reach is envisaged.
- Published
- 2014
26. Cones in the space of block-matrices
- Author
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Tsuyoshi Ando
- Subjects
Applied Mathematics ,Analysis - Published
- 2013
27. Unbounded or bounded idempotent operators in Hilbert space
- Author
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Tsuyoshi Ando
- Subjects
Discrete mathematics ,Numerical Analysis ,Algebra and Number Theory ,Hilbert space ,law.invention ,Linear map ,symbols.namesake ,Invertible matrix ,Operator (computer programming) ,law ,Bounded function ,Idempotence ,symbols ,Discrete Mathematics and Combinatorics ,Geometry and Topology ,Mathematics - Abstract
A densely defined, closed linear operator F in a Hilbert space is said to be idempotent if ran ( F ) ⊂ dom ( F ) and F · F = F . We show that such an idempotent operator is written as F = P ( P + Q ) - 1 / 2 · ( P + Q ) - 1 / 2 where P and Q are the orthoprojections to ran ( F ) and ker ( F ) , respectively. When F is bounded, this becomes F = P ( P + Q ) - 1 . Further we show that for any λ ≠ 0 the operator P + λ Q is invertible and F = P ( P + λ Q ) - 1 . In addition to the known results we present several descriptions of the norm ‖ F ‖ in terms of ‖ P + Q ‖ , ‖ ( P + Q ) - 1 ‖ or ‖ ( P - Q ) - 1 ‖ .
- Published
- 2013
28. Synthesis and photoproperties of Eu(III)-bearing star polymers as luminescent materials
- Author
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Tsuyoshi Ando, Shiho Hirohara, Kayo Terada, Tsuyoshi Kawai, Masao Tanihara, Ahmad Kusumaatmaja, Takuya Nakashima, and Takaya Terashima
- Subjects
chemistry.chemical_classification ,Aqueous solution ,Materials science ,Polymers and Plastics ,Ethylene oxide ,Organic Chemistry ,Radical polymerization ,chemistry.chemical_element ,One-Step ,Polymer ,chemistry.chemical_compound ,chemistry ,Polymer chemistry ,Materials Chemistry ,Methyl methacrylate ,Europium ,Luminescence - Abstract
Water-soluble luminescent material was developed by introducing europium (Eu(III)) ions into the core of a star polymer. Living radical polymerization was used to obtain the star polymer. The strategy to introduce Eu(III) ions into the star polymer was studied using poly(methyl methacrylate) as an arm. The best Eu(III) ion introduction was obtained by simultaneous introduction, resulting in about 30 µmol/g-polymer, which needed only one step for synthesis. The utilization of a hydrophilic polymer such as poly(ethylene oxide) (PEO) as an arm produced a water-soluble star polymer. The Eu(III)-bearing PEO star polymer obtained in this study was water soluble and showed fluorescence. In addition, it was stable in water after 1 month. The Eu(III)-bearing star polymer exhibited luminescent properties under UV light irradiation with relatively high quantum yields of 60% in organic solution and 19% in aqueous solution. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2527–2535
- Published
- 2013
29. Vaccination with Antigen-Transfected, NKT Cell Ligand–Loaded, Human Cells Elicits Robust In Situ Immune Responses by Dendritic Cells
- Author
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Kanako Shimizu, Tsuyoshi Ando, Yasuyuki Ishii, Miki Asakura, Tomoji Maeda, Shin-ichiro Fujii, Jan Dörrie, Takuya Mizuno, Kenichi Masuda, Hirokazu Matsushita, Ryozo Nagai, Hidetoshi Sugahara, Keigo Nishida, Hisashi Koike, Ken-ichi Hanada, Kara Bickham, Kazuhiro Kakimi, Yusuke Sato, Niels Schaft, and Jun Shinga
- Subjects
Cancer Research ,medicine.medical_treatment ,chemical and pharmacologic phenomena ,Adaptive Immunity ,Biology ,Lymphocyte Activation ,Transfection ,Cancer Vaccines ,Mice ,Cross-Priming ,Dogs ,Immune system ,Cancer immunotherapy ,Antigen ,Antigens, Neoplasm ,Immunity ,medicine ,Animals ,Humans ,HEK 293 cells ,Dendritic Cells ,Flow Cytometry ,Acquired immune system ,Immunity, Innate ,Mice, Inbred C57BL ,Immunosurveillance ,HEK293 Cells ,Oncology ,CD1D ,Immunology ,Cancer research ,biology.protein ,Natural Killer T-Cells - Abstract
Both innate and adaptive immunity are crucial for cancer immunosurveillance, but precise therapeutic equations to restore immunosurveillance in patients with cancer patients have yet to be developed. In murine models, α-galactosylceramide (α-GalCer)–loaded, tumor antigen–expressing syngeneic or allogeneic cells can act as cellular adjuvants, linking the innate and adaptive immune systems. In the current study, we established human artificial adjuvant vector cells (aAVC) consisting of human HEK293 embryonic kidney cells stably transfected with the natural killer T (NKT) immune cell receptor CD1d, loaded with the CD1d ligand α-GalCer and then transfected with antigen-encoding mRNA. When administered to mice or dogs, these aAVC-activated invariant NKT (iNKT) cells elicited antigen-specific T-cell responses with no adverse events. In parallel experiments, using NOD/SCID/IL-2rγcnull–immunodeficient (hDC-NOG) mouse model, we also showed that the human melanoma antigen, MART-1, expressed by mRNA transfected aAVCs can be cross-presented to antigen-specific T cells by human dendritic cells. Antigen-specific T-cell responses elicited and expanded by aAVCs were verified as functional in tumor immunity. Our results support the clinical development of aAVCs to harness innate and adaptive immunity for effective cancer immunotherapy. Cancer Res; 73(1); 62–73. ©2012 AACR.
- Published
- 2013
30. Transfer hydrogenation of ketones catalyzed by PEG-armed ruthenium-microgel star polymers: microgel-core reaction space for active, versatile and recyclable catalysis
- Author
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Tsuyoshi Ando, Makoto Ouchi, Takaya Terashima, and Mitsuo Sawamoto
- Subjects
chemistry.chemical_classification ,Polymers and Plastics ,Chemistry ,Ethylene glycol dimethacrylate ,Radical polymerization ,chemistry.chemical_element ,Polymer ,Transfer hydrogenation ,Photochemistry ,Ruthenium ,Catalysis ,chemistry.chemical_compound ,Polymer chemistry ,Materials Chemistry ,Methyl methacrylate ,Ethylene glycol - Abstract
Poly(ethylene glycol) (PEG)-armed Ru(II)-bearing microgel-core star polymer catalysts were used for the transfer hydrogenation of ketones. The star catalysts (Ru(II)-PEG Star) were one-pot synthesized by ruthenium-catalyzed living radical polymerization of poly(ethylene glycol) methyl ether methacrylate (PEGMA) and a sequential linking reaction with ethylene glycol dimethacrylate (1) and diphenylphosphinostyrene (2). The polymers efficiently and homogeneously reduced acetophenone into 1-phenylethanol in 2-propanol coupled with K2CO3 at a high yield, despite a low catalyst feed ratio to the substrate (Ru(II)/substrate=1/1000). Importantly, the catalytic activity was higher than that of the original RuCl2(PPh3)3, as well as that of similar polymer-supported Ru(II) catalysts, such as poly(methyl methacrylate)-armed star-, polystyrene gel- and random polymer-supported catalysts. Ru(II)-PEG Star is applicable to various substrates, including para-substituted aromatic, aliphatic and bulky ketones, where the activity of Ru(II)-PEG Star is is generally higher than that of RuCl2(PPh3)3. For example, the turnover frequency for 4-chloroacetophenone and cyclohexanone reached ∼1000 h−1, and the reduction rate of cyclopentanone and 3-methyl-5-heptanone was twice as high as that of RuCl2(PPh3)3. The star catalyst also showed high catalyst recyclability, independent of the substrate species. These features most likely arise from its unique reaction space, which consists of a ruthenium-embedded, hydrophobic microgel core surrounded by amphiphilic and polar PEGMA arms. Poly(ethylene glycol)-armed Ru(II)-bearing microgel star polymers, directly obtained from ruthenium-catalyzed living radical polymerization, were used as catalysts for transfer hydrogenation of ketones in 2-propanol. Owing to the good affinity of the core-reaction pocket and the surrounding arms to substrates and products, respectively, the star polymer catalysts homogeneously hydrogenated various ketones into the corresponding alcohols more efficiently than the other polymer-supported catalysts and the original ruthenium counterpart. The catalyst encapsulation into the unique microgel core further afforded efficient catalyst recycle and facile product recovery.
- Published
- 2011
31. Oxidation of sec‐alcohols with Ru(II)‐bearing microgel star polymer catalysts via hydrogen transfer reaction: Unique microgel‐core catalysis
- Author
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Makoto Ouchi, Tsuyoshi Ando, Takaya Terashima, and Mitsuo Sawamoto
- Subjects
chemistry.chemical_classification ,Ketone ,Polymers and Plastics ,Catalyst support ,Ethylene glycol dimethacrylate ,Organic Chemistry ,Radical polymerization ,chemistry.chemical_element ,Catalysis ,Ruthenium ,chemistry.chemical_compound ,chemistry ,Polymer chemistry ,Materials Chemistry ,Methyl methacrylate ,Acetophenone - Abstract
Oxidation of sec-alcohols was investigated with ruthenium-bearing microgel core star polymer catalysts [Ru(II)-Star]. The star polymer catalysts were directly prepared via RuCl2(PPh3)3-catalyzed living radical polymerization of methyl methacrylate (MMA), followed by the arm-linking reaction with ethylene glycol dimethacrylate (1) in the presence of diphenylphosphinostyrene (2). The Ru(II)-Star efficiently and homogeneously catalyzed the oxidation of 1-phenylethanol (S1) to give a corresponding ketone (acetophenone) in higher yield (92%) than the analogs of polymer-supported ruthenium complexes. Importantly, the star catalyst afforded high recycling efficiency in the oxidation. They held catalytic activity against three times catalysis even though they were recovered under air-exposure, whereas the conventional RuCl2(PPh3)3 lost the activity for same recycling procedure due to the deactivation by oxygen. The stability of the star catalysts during the recycle experiment was confirmed by detailed spectroscopic characterization. The star polymers also catalyzed oxidation for a wide range of sec-alcohols with aromatic and aliphatic groups. The substrate affinity was different from that with RuCl2(PPh3)3, suggesting the unique selectivity caused by the specific structure. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011.
- Published
- 2011
32. Collagen-like polypeptide poly(Pro-Hyp-Gly) conjugated with Gly-Arg-Gly-Asp-Ser and Pro-His-Ser-Arg-Asn peptides enhances cell adhesion, migration, and stratification
- Author
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Tsuyoshi Ando, Yoshiaki Shibasaki, Shiho Hirohara, Kayo Terada, and Masao Tanihara
- Subjects
Scaffold ,Antigenicity ,Biocompatibility ,Biophysics ,Conjugated system ,Biochemistry ,Biomaterials ,Mice ,Cell Movement ,Gly-Arg-Gly-Asp-Ser ,Cell Adhesion ,Animals ,Humans ,Cell adhesion ,Tissue Scaffolds ,biology ,Chemistry ,Organic Chemistry ,Cell migration ,General Medicine ,Fibronectins ,Cell biology ,Fibronectin ,NIH 3T3 Cells ,biology.protein ,Cattle ,Collagen ,Rabbits ,Peptides - Abstract
Collagens are widely used in medical applications, including as a scaffold for tissue regeneration. However, animal-derived collagens have several drawbacks, such as low thermal stability, nonspecific cell adhesion, antigenicity, and contamination with pathogenic substances. To overcome these problems, we chemically synthesized the collagen-like polypeptide, poly(prolyl-hydroxyprolyl-glycyl) (poly(Pro-Hyp-Gly)), which forms a collagen-like triple-helical structure and shows biodegradability and biocompatibility. Here, we designed a novel scaffold where fibronectin-derived Gly Arg-Gly-Asp-Ser (GRGDS) and Pro-His-Ser-Arg-Asn (PHSRN) peptides were simultaneously conjugated with poly(Pro-Hyp-Gly). We assessed cell adhesion and migration activities using NIH3T3 cells in the scaffold and stratification ofimmortalized rabbit corneal epithelial cells. Cell adhesion was enhanced in scaffolds with GRGDS, increased with increasing amounts of conjugated GRGDS, and was significantly higher than bovine type I atelocollagen but lower than bovine fibronectin. Interestingly, simultaneous conjugation of GRGDS and PHSRN synergistically enhanced cell migration. Scaffolds containing almost equal amounts of GRGDS and PHSRN showed significantly higher cell migration than bovine type I atelocollagen. Addition of free GRGDS completely inhibited cell migration on the scaffold, whereas addition of free PHSRN partially inhibited cell migration. These results suggest that GRGDS plays a definitive role, and PHSRN plays an additional role, in cell migration. Conjugation of GRGDS resulted in the same level of stratification of rabbit corneal epithelial cells compared with bovine type I atelocollagen and bovine fibronectin. Because the simultaneous conjugation of GRGDS and PHSRN on poly(Pro-Hyp-Gly) enhances cell adhesion, migration, and stratification, it may be a useful scaffold for tissue regeneration.
- Published
- 2010
33. Operator log-convex functions and operator means
- Author
-
Tsuyoshi Ando and Fumio Hiai
- Subjects
Mathematics - Functional Analysis ,Discrete mathematics ,Operator (computer programming) ,Monotone polygon ,Logarithmically convex function ,General Mathematics ,47A63, 47A64, 15A45 ,FOS: Mathematics ,Nonnegative function ,Bitwise operation ,Functional Analysis (math.FA) ,Mathematics - Abstract
We study operator log-convex functions on $(0,\infty)$, and prove that a continuous nonnegative function on $(0,\infty)$ is operator log-convex if and only if it is operator monotone decreasing. Several equivalent conditions related to operator means are given for such functions. Operator log-concave functions are also discussed., Comment: 20 pages
- Published
- 2010
34. Anticoagulant activity of enzymatically synthesized amylose derivatives containing carboxy or sulfonate groups
- Author
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Masao Tanihara, Kayo Terada, Michihiro Sunako, Kayo Hosoya, Shiho Hirohara, Tsuyoshi Ando, and Junichi Takahara
- Subjects
Magnetic Resonance Spectroscopy ,Time Factors ,Phosphorylases ,medicine.drug_class ,Sus scrofa ,Carboxylic Acids ,Biomedical Engineering ,Polysaccharide ,Biochemistry ,Biomaterials ,Thrombin ,Prothrombinase ,Spectroscopy, Fourier Transform Infrared ,medicine ,Animals ,Humans ,Molecular Biology ,chemistry.chemical_classification ,Chemistry ,Hydrolysis ,Antithrombin ,Anticoagulant ,Anticoagulants ,General Medicine ,Heparin ,Enzyme ,Coagulation ,Factor Xa ,Chromatography, Gel ,Potentiometry ,Biological Assay ,Cattle ,Amylose ,Sulfonic Acids ,Factor Xa Inhibitors ,Biotechnology ,medicine.drug - Abstract
Heparin is an extracellular matrix polysaccharide. It is widely employed as an anticoagulant and can be used to form an anticoagulant surface on various medical devices such as renal dialysis devices to prevent thrombosis. However, heparin may cause hemorrhage and thrombocytopenia. Moreover, commercially available heparin may be contaminated with viruses and allergens of animal origin, as it is derived mainly from porcine or bovine tissue. To avoid these problems, we prepared succinated and sulfonated enzymatically synthesized amylose (SucESA and SulfESA, respectively) and assessed their anticoagulant activity. SucESA and SulfESA inhibited factor Xa activity in normal human plasma to an equal extent. However, SucESA strongly inhibited thrombin activity, whereas SulfESA only inhibited it slightly. These results suggest that SucESA inhibits the activities of both factor Xa (or its upstream coagulation factors) and thrombin and that SulfESA inhibits only factor Xa activity (or that of its upstream coagulation factors). SucESA and SulfESA with a high degree of substitution strongly inhibited factor Xa and thrombin activity compared with those of the derivatives with a low degree of substitution, even when present in high concentrations. This suggests that the density of the anion group determines the degree of inhibition of factor Xa and thrombin activity. SucESA, which has a high molecular weight, inhibited thrombin activity to a greater degree than low molecular weight SucESA. Because SucESA and SulfESA inhibited both purified factor Xa and thrombin irrespective of the presence of antithrombin, it is suggested that SucESA and SulfESA inhibit via direct action with both enzymes.
- Published
- 2010
35. (Invited) Designed Polymers for Antifouling Surfaces
- Author
-
Tsuyoshi Ando, Masayasu Totani, and Ikuo Yamamoto
- Abstract
There is a strong demand for antifouling surface. To create such antifouling surface, there are some approaches such as chemical reaction at the surface, coatings, internal additives, etc. We are developing polymers that can modify the surface property by easy treatments based on precise design and synthesis of the polymers. Biomedical synthetic materials, such as poly(ethylene terephthalate) (PET) and polypropylene (PP), are prone to adhesion of proteins, cells, and bacteria, causing functional failures in implants, artificial organs, catheters, and diagnostic devices, and increasing the risk of secondary infections. One of the promising answers is a hydrophilic polymer brush surface on which many polymer chains are connected in high density to inhibit adsorption of proteins and following adhesion of related biomolecules and cells. Such high density polymer brush is usually built by surface-initiated living radical polymerization through several chemical steps and polymers applied for medical devices are rather inert to chemical modification than inorganic materials. We thus created a new star shaped heteroarm polymer consisting of hydrophilic chains, as an antifouling block, and hydrophobic chains, as a substrate attaching block, for a biocompatible coating material, which is supposed to form polymer brush-like structure by simple coating procedure. The coating surface exhibited very good resistance to adhesion of platelets, bacteria, fibroblasts, and proteins although the corresponding linear polymer exhibited moderate resistance. This result indicates utilization of unique architecture of the star polymer is effective for building condensed polymer brush structure at the surface. Perfluoroalkyl group-containing polymer shows water/oil repellency. Although long perfluoroalkyl groups (longer than C8) exhibit high repellency, they can not be employed because of the environmental reason, nowadays. Shorter perfluoroalkyl groups (less than C8) give less effect to environment but they have less repellency. We thud designed block copolymers consisting of fluorine and non-fluorine containing monomers and evaluated the sequence effects as an internal additive to PP resin to improve oil repellency. By controlling fluorinated/non-fluorinated monomer sequence, the oil repellency of the fluorinated polymer-added polypropylene (PP) was dramatically improved compared to that modified with the randomly sequenced fluoropolymer. For instance, random copolymer consisting of 2-(perfluorohexyl)ethyl methacrylate (C6FMA) and stearyl methacrylate (StMA) gave slightly higher contact angle (13º) than that of non-additive PP (6º). Compared to the random copolymer, the diblock and triblock copolymer lead much higher contact angles (23º and 38º, respectively) when only 1wt% of the fluoropolymer was mixed into PP. This result indicates sequence regulation of fluorinated/non-fluorinated monomer in the fluoropolymer is effective to concentrate fluorine groups at the resin surface resulting in improvement of water/oil repellency.
- Published
- 2018
36. Rapid Diagnostic for Zika virus infection
- Author
-
Hidetaka Minakawa, Kazuyoshi Miyamoto, Katsumi Aoyagi, Tomoe Honda, Yoshiaki Uchida, Toshihiro Niwa, Kazuya Omi, and Tsuyoshi Ando
- Subjects
biology ,business.industry ,Applied Mathematics ,General Mathematics ,Medicine ,biology.organism_classification ,business ,Virology ,Zika virus - Published
- 2018
37. Functional calculus with operator-monotone functions
- Author
-
Tsuyoshi Ando
- Subjects
Algebra ,Operator (computer programming) ,Monotone polygon ,Applied Mathematics ,General Mathematics ,Mathematics ,Functional calculus - Published
- 2010
38. Operator radii and unitary operators
- Author
-
Tsuyoshi Ando and Chi-Kwong Li
- Subjects
Pure mathematics ,Algebra and Number Theory ,Multiplication operator ,Displacement operator ,Unitary operator ,Finite-rank operator ,Operator theory ,Shift operator ,Compact operator ,Analysis ,Mathematics ,Quasinormal operator - Abstract
Let ρ 1 and wρ(A) be the operator radius of a linear operator A . Suppose m is a positive integer. It is shown that for a given invertible linear operator A acting on a Hilbert space, one has wρ (A−m) wρ (A)−m . The equality holds if and only if A is a multiple of a unitary operator. Mathematics subject classification (2010): 47A20, 47A12, 15A60.
- Published
- 2010
39. Thermoregulated phase-transfer catalysis via PEG-armed Ru(II)-bearing microgel core star polymers: Efficient and reusable Ru(II) catalysts for aqueous transfer hydrogenation of ketones
- Author
-
Makoto Ouchi, Mitsuo Sawamoto, Takaya Terashima, and Tsuyoshi Ando
- Subjects
chemistry.chemical_classification ,Aqueous solution ,Polymers and Plastics ,Catalyst support ,Organic Chemistry ,Radical polymerization ,Transfer hydrogenation ,Photochemistry ,Catalysis ,Styrene ,chemistry.chemical_compound ,chemistry ,Polymer chemistry ,Materials Chemistry ,Living polymerization ,Alkyl - Abstract
Thermoregulated phase-transfer catalysis for the transfer hydrogenation of 2-octanone in 2-propanol/H2O biphasic media was achieved with ruthenium-bearing microgel-core star polymers with amphiphilic, thermosensitive poly(ethylene glycol) (PEG) arms [Ru(II)-PEG star], which were directly prepared by the ruthenium-catalyzed living radical polymerization in conjunction with a phosphine ligand-carrying styrene derivative. The star polymers were first placed in the aqueous (lower) layer at room temperature and immediately moved into the organic (upper) layer at 100 °C, and once again, moved down to the aqueous layer (lower) upon cooling the solution to room temperature. The Ru(II)-PEG star catalyst was clearly superior to the original Ru(II) catalyst and related non-microgel catalysts [Ru(II)-PEG block] in terms of activity and recovery/recycle, due to the unique designer structure of the microgel-core star polymers. Other substrates (less hydrophobic alkyl ketones and aromatic ketone) were also efficiently hydrogenated into the corresponding sec-alcohols with the star catalyst in aqueous media. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 373–379, 2010
- Published
- 2009
40. Projections in Krein spaces
- Author
-
Tsuyoshi Ando
- Subjects
Discrete mathematics ,Numerical Analysis ,Pure mathematics ,J-positive projection ,Algebra and Number Theory ,Mathematics::Spectral Theory ,Regular subspace ,Linear subspace ,J-projection ,Krein space ,Discrete Mathematics and Combinatorics ,J-contractive operator ,Canonical form ,Geometry and Topology ,Contraction (operator theory) ,Subspace topology ,Mathematics ,Vector space - Abstract
Let ( H , J ) be a Krein space with selfadjoint involution J . Starting with a canonical representation of a J -selfadjoint projection, J -projection in short, as the sum of a J -positive projection and a J -negative one we study in detail the structure of a regular subspace, that is, the range of a J -projection. We treat the problem when the sum of two regular subspaces is again regular. We also treat the problem when the closure of the range of the product of a J -contraction and a J -expansion becomes regular.
- Published
- 2009
41. Evolution of iron catalysts for effective living radical polymerization: P-N chelate ligand for enhancement of catalytic performances
- Author
-
Chihiro Uchiike, Masami Kamigaito, Mitsuo Sawamoto, Makoto Ouchi, and Tsuyoshi Ando
- Subjects
Living free-radical polymerization ,Nitroxide mediated radical polymerization ,Polymers and Plastics ,Cobalt-mediated radical polymerization ,Polymerization ,Chemistry ,Organic Chemistry ,Radical polymerization ,Polymer chemistry ,Materials Chemistry ,Living polymerization ,Solution polymerization ,Ionic polymerization - Abstract
Iron catalysts were evolved for more active transition metal-catalyzed living radical polymerization through design of the ligands. In situ introduction of P-N chelate-ligands, consisting of hetero-coordinating atoms [phosphine (P) and nitrogene (N)], onto FeBr 2 effectively catalyzed living radical polymerization of methyl methacrylate (MMA) in conjunction with a bromide initiator, where the monomer-conversion reached over 90% without dropping the rates and the molecular weights of obtained PMMAs were well controlled. The benign effects of the "hetero-chelation" were demonstrated by comparative experiments with homo-chelate ligands (P-P, N-N), model compounds of the composed coordination site, and the combinations. We successfully achieved an isolation of iron complex with a P-N ligand [FeBr 2 (DMDPE); DMDPE: (R)-N,N-dimethyl-1-(2-(diphenylphosphino)phenyl)-ethanamine], which was superior to the conventional catalyst [FeBr 2 (Pn-Bu) 2 ] with respect to controllability and activity, especially at the latter stage. The catalyst was almost quantitatively removed by water washing after polymerization. It was also effective for living polymerization of styrene.
- Published
- 2008
42. Fine Structures of Laser-Driven Punched-Out Tin Fuels Observed with Extreme Ultraviolet Backlight Imaging
- Author
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Hiroaki Nishimura, Katsunobu Nishihara, Yoshinori Shimada, Takayoshi Norimatsu, Yuzuri Yasuda, Yasukazu Izawa, Tomoya Birou, Shinsuke Maeda, Shinsuke Fujioka, Noriaki Miyanaga, Tsuyoshi Ando, Kunioki Mima, and Keiji Nagai
- Subjects
Materials science ,Physics and Astronomy (miscellaneous) ,business.industry ,Extreme ultraviolet lithography ,General Engineering ,General Physics and Astronomy ,chemistry.chemical_element ,Backlight ,Laser ,law.invention ,Optics ,Light source ,chemistry ,Critical parameter ,law ,Extreme ultraviolet ,Optoelectronics ,Small particles ,business ,Tin - Abstract
The laser-driven punched-out scheme, which has been proposed for supplying minimum-mass tin fuels at a high repetition rate, was investigated for use in an extreme ultraviolet (EUV) light source. The density profile of punched-out tin fuel is a critical parameter for validating applicability of this scheme. An EUV backlight technique was developed to measure the density profile and fine structure. Experimental results reveal that a punched-out target does not remain its initial thin shape, but expands into a rarefied gas and liquid and small particles under the present target and laser conditions.
- Published
- 2008
43. Positivity of operator-matrices of Hua-type
- Author
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Tsuyoshi Ando
- Subjects
Algebra and Number Theory ,Open unit ,positivity ,Operator (physics) ,Mathematical analysis ,Hilbert space ,Type (model theory) ,15A45 ,operator-matrix ,Combinatorics ,symbols.namesake ,Operator matrix ,47B63 ,symbols ,Always true ,Hua theorem ,47B15 ,Analysis ,strict contraction ,Mathematics - Abstract
Let $A_j\,\,(j = 1, 2,\ldots , n)$ be strict contractions on a Hilbert space. We study an $n \times n$ operator-matrix: \[\textbf{H}_n(A_1,A_2,\ldots ,A_n) = [(I - A^*_j A_i)^{-1}]^n_{i,j=1}.\] For the case $n = 2$, Hua [Inequalities involving determinants, Acta Math. Sinica, 5 (1955), 463-470 (in Chinese)] proved positivity, i.e., positive semi-definiteness of $\textbf{H}_2(A_1,A_2)$. This is, however, not always true for $n = 3$. First we generalize a known condition which guarantees positivity of $\textbf{H}_n$. Our main result is that positivity of $\textbf{H}_n$ is preserved under the operator M\"obius map of the open unit disc $\mathcal D$ of strict contractions.
- Published
- 2008
44. Evolution of Iron Catalysts for Effective Living Radical Polymerization: Design of Phosphine/Halogen Ligands in FeX2(PR3)2
- Author
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Tsuyoshi Ando, Mitsuo Sawamoto, Masami Kamigaito, Makoto Ouchi, Chihiro Uchiike, and Takaya Terashima
- Subjects
Polymers and Plastics ,Organic Chemistry ,Radical polymerization ,Catalysis ,Inorganic Chemistry ,chemistry.chemical_compound ,Monomer ,chemistry ,Polymerization ,Bromide ,Polymer chemistry ,Halogen ,Materials Chemistry ,Organic chemistry ,Methyl methacrylate ,Phosphine - Abstract
In this article, we report the evolved system of iron-complex-catalyzed living radical polymerization of methyl methacrylate (MMA), through design of the ligand, combination of the halogen in the initiator/catalyst, and optimization of the polymerization conditions, toward improvement of the activity and the polymerization-controllability with the applicable catalysts. Introduction of the more basic ligands such as PMe(Ph)2 and P-n-Bu3 in place of PPh3 in the conventional iron catalyst [FeX2(PPh3)2; X = Cl, Br] improved the catalytic performances such as the activity/controllability. In particular, the butylphosphine bromide derivative [FeBr2(P-n-Bu3)2] in conjunction with a bromide initiator [(MMA)2Br] allowed a faster and more precise polymerization, where the conversion reached over 90% without serious deactivation and the molecular weights and their distributions of the obtained PMMAs were fairly controlled (Mw/Mn = 1.2−1.3). The high efficiency of the system was demonstrated by the successful monomer...
- Published
- 2007
45. Norm Estimates of the Partial Transpose Map on the Tensor Products of Matrices
- Author
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Takashi Sano and Tsuyoshi Ando
- Subjects
Mathematics::Combinatorics ,Mathematics::Commutative Algebra ,Invariance principle ,Mathematics::Operator Algebras ,General Mathematics ,Mathematical analysis ,Matrix norm ,Operator theory ,Theoretical Computer Science ,Combinatorics ,Tensor product ,Mathematics::K-Theory and Homology ,Mathematics::Quantum Algebra ,Transpose ,Analysis ,Norm estimate ,Mathematics - Abstract
We present a norm estimate for the partial transpose map Θ on the tensor product \(M_m \otimes M_n\) $$\Theta \left( \sum_k A_k \otimes B_k \right) := \sum_k A_k \otimes B_k^T$$ with respect to a unitarily invariant norm. This is related to the norm estimates of the following maps on Mm,n in terms of the spectral norm of \(\displaystyle \sum_k A_k \otimes B_k\) : $$X \longmapsto \sum_k A_k X B_k \quad \textrm{and} \quad X \longmapsto \sum_k A_k X B_k^T.$$ We show further that in the special case of \(A \otimes I_n + I_m \otimes B\) as well as AX + XB and AX + XBT those estimates are much improved and that $$\| A \otimes I_n + I_m \otimes B^T \|_p = \| A \otimes I_n + I_m \otimes B \|_p$$ for certain Schatten p-norms.
- Published
- 2007
46. Amphiphilic, Thermosensitive Ruthenium(II)-Bearing Star Polymer Catalysts: One-Pot Synthesis of PEG Armed Star Polymers with Ruthenium(II)-Enclosed Microgel Cores via Metal-Catalyzed Living Radical Polymerization
- Author
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Takaya Terashima, Makoto Ouchi, Tsuyoshi Ando, Mitsuo Sawamoto, and Masami Kamigaito
- Subjects
chemistry.chemical_classification ,Polymers and Plastics ,Organic Chemistry ,Radical polymerization ,chemistry.chemical_element ,Polymer ,Methacrylate ,Ruthenium ,Inorganic Chemistry ,chemistry.chemical_compound ,Monomer ,chemistry ,Polymerization ,Polymer chemistry ,Materials Chemistry ,Copolymer ,Methyl methacrylate - Abstract
Amphiphilic and thermosensitive star polymers with Ru(II) complex−encapsulating microgel cores were directly synthesized in high yield via RuCl2(PPh3)3-catalyzed living radical polymerization. For the solvo- and thermal responsiveness, the arms stem from a block copolymer of poly(ethylene glycol) methyl ether methacrylate (PEGMA) with a small amount of methyl methacrylate. For the metal encapsulation into the core, a phosphine-ligand monomer [CH2CH(C6H4)PPh2] was “copolymerized” with a divinyl compound (linking agent); upon block polymer formation, in situ addition of these two components induced the linking reaction of the arm chains and, subsequently, the formation of Ru(II)-bearing microgels (cores) via ligand exchange between the triphenylphoshines in the original catalyst and the pendent phosphines in the core network. Thus, the hydrophobic catalyst [RuCl2(PPh3)3] for polymerization was in situ transformed into an amphiphilic core-bound catalyst. The star polymers with different Ru(II) contents were ...
- Published
- 2007
47. Noncompetitive immunoassay detection system for haptens on the basis of antimetatype antibodies
- Author
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Yoshiaki Uchida, Takashi Shirakawa, Takuya Sakyu, Nobuyuki Ise, Tsuyoshi Ando, Kazuya Omi, Katsutoshi Goishi, Asako Oka, and Katsumi Aoyagi
- Subjects
Analyte ,medicine.drug_class ,Clinical Biochemistry ,Monoclonal antibody ,Sensitivity and Specificity ,law.invention ,Microtiter plate ,law ,Limit of Detection ,medicine ,Humans ,Vitamin D ,Chemiluminescence ,Detection limit ,Immunoassay ,Chromatography ,biology ,medicine.diagnostic_test ,Estradiol ,Chemistry ,Biochemistry (medical) ,Antibodies, Monoclonal ,biology.protein ,Antibody ,Hapten ,Haptens - Abstract
BACKGROUND Small molecules classified as haptens are generally measured by competitive immunoassay, which is theoretically inferior to noncompetitive sandwich immunoassay in terms of sensitivity and specificity. We created a method for developing sandwich immunoassays to measure haptens on the basis of antimetatype antibodies. METHODS We generated antimetatype monoclonal antibodies against a hapten–antibody immunocomplex using an ex vivo antibody development system, the Autonomously Diversifying Library (ADLib) system. We selected 2 haptens, estradiol (E2) and 25-hydroxyvitamin D [25(OH)D], as analytes. Sandwich immunoassays for these 2 haptens were developed by use of a 96-well microtiter plate and a fully automated chemiluminescence analyzer, and the performances of these immunoassays were investigated. RESULTS The developed assays exhibited sensitivity high enough to detect target haptens in serum samples. The limit of detection of the ELISA for E2 was 3.13 pg/mL, and that of the fully automated chemiluminescent enzyme immunoassay (CLEIA) system was 2.1 ng/mL for 25(OH)D. The cross-reactivity with immunoreactive derivatives was effectively improved compared with the competitive assay. The CVs for the sandwich ELISA for E2 were 4.2%–12.6% (intraassay) and 6.2%–21.8% (total imprecision). The CVs for the sandwich CLEIA for 25(OH)D were 1.0%–2.3% (intraassay) and 1.9%–3.5% (total imprecision). In particular, the sandwich CLEIA for 25(OH)D showed correlations of r = 0.99 with both LC-MS/MS and a commercially available 125I RIA. CONCLUSIONS Our method represents a potentially simple and practical approach for routine assays of haptens, including vitamins, hormones, drugs, and toxins.
- Published
- 2015
48. EUV and particle generations from laser-irradiated solid- and low-density targets
- Author
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Qincui Gu, Katsunobu Nishihara, Y. Tao, Atsushi Sunahara, Tatsuya Aota, Keiji Nagai, N. Miyanaga, K. Gamada, Yuzuri Yasuda, Michiteru Yamaura, Shigeaki Uchida, Y. Shimada, Y. Norimatsu, YG Kang, Hiroaki Nishimura, K. Mima, Tsuyoshi Ando, Nobuyoshi Ueda, K. Hashimoto, M. Murakami, Shinsuke Fujioka, Y. Izawa, Tomoharu Okuno, and Hiromitsu Furukawa
- Subjects
Opacity ,Chemistry ,law ,Extreme ultraviolet ,Extreme ultraviolet lithography ,General Physics and Astronomy ,Emission spectrum ,Plasma ,Atomic physics ,Laser ,Spectral line ,Charged particle ,law.invention - Abstract
Properties of extreme ultraviolet (EUV) and particle emissions from laser-produced tin (Sn) plasma were experimentally investigated for use in industrial applications. Dependence of EUV emission on the initial thickness of Sn overcoat on a plastic sphere was studied to clarify the minimum mass needed to keep sufficient conversion to EUV and minimize plasma debris. EUV emission from low-density targets showed narrower spectra peaked at 13.5nm, attributed to reduction of satellite line emissions in the spectrum foot and opacity broadening at the peak. It is shown that not only the EUV generation but also ion spectra are significantly affected by the Sn coat thicknesses.
- Published
- 2006
49. Metal-complex-bearing star polymers by metal-catalyzed living radical polymerization: Synthesis and characterization of poly(methyl methacrylate) star polymers with Ru(II)-embedded microgel cores
- Author
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Takaya Terashima, Mitsuo Sawamoto, Tsuyoshi Ando, Makoto Ouchi, and Masami Kamigaito
- Subjects
chemistry.chemical_classification ,polymer catalyst ,Polymers and Plastics ,living polymerization ,Ethylene glycol dimethacrylate ,Organic Chemistry ,Radical polymerization ,star polymers ,Polymer ,Methacrylate ,radical polymerization ,Poly(methyl methacrylate) ,microgel core ,polymer linking ,ruthenium complex ,chemistry.chemical_compound ,chemistry ,Polymerization ,visual_art ,Polymer chemistry ,Materials Chemistry ,visual_art.visual_art_medium ,Living polymerization ,Methyl methacrylate - Abstract
One-pot, spontaneous, and in-situ incorporation of Ru(II) complexes into a microgel (solubilized nanometer-scale network) has been achieved in near quantitative efficiency by a polymer-linking reaction of linear living poly(methyl methacrylate) (PMMA) with a bifunctional methacrylate (ethylene glycol dimethacrylate or bisphenol A dimethacrylate; linking agent) and a phosphine-ligand monomer [diphenyl-4-styryl-phosphine (3); i.e., CH2CHC6H4p-PPh2] in the RuCl2(PPh3)3-catalyzed living radical polymerization. The products were Ru-bearing. PMMA-armed star polymers with a microgel-core that consisted of a copolymer network of the linking agent and 3. Upon the network formation, the phosphine ligands efficiently encapsulated RuCl2(PPh3)3, thus achieving a polymer catalyst directly from a polymerization catalyst. Colored dark brown-red, the star polymers exhibited UV-vis absorptions originating from the entrapped complex (3.1–7.4 × 10−5 mol Ru/g of polymer), the incorporation efficiency being close to 100% with respect to the original polymerization-catalyst. Detailed spectroscopic characterization showed the following: an absolute molecular weight of 1.7 × 105 to 1.7 × 106, an arm number of 11–92 arms/polymer, and a radius of gyration of 8–19 nm (in DMF). Direct observation of the individual star molecules in solid state was achieved by transmission electron microscopy (unstained; 2–3 nm dark dots for the core) and atomic force microscopy (semi-circular images). © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 4966–4980, 2006
- Published
- 2006
50. Utilization of star-shaped polymer architecture in the creation of high-density polymer brush coatings for the prevention of platelet and bacteria adhesion
- Author
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Chikara Ohtsuki, Masayasu Totani, Ill Yong Kim, Chuanwu Xi, Tsuyoshi Ando, Takaya Terashima, Masao Tanihara, Kayo Terada, and Kenichi Kuroda
- Subjects
chemistry.chemical_classification ,endocrine system ,Materials science ,Radical polymerization ,Biomedical Engineering ,Star-shaped polymer ,Adhesion ,Polymer ,engineering.material ,Polymer brush ,Methacrylate ,Article ,chemistry.chemical_compound ,Coating ,chemistry ,Chemical engineering ,Polymer chemistry ,engineering ,General Materials Science ,Methyl methacrylate - Abstract
We demonstrate utilization of star-shaped polymers as high-density polymer brush coatings and their effectiveness to inhibit the adhesion of platelets and bacteria. Star polymers consisting of poly(2-hydroxyethyl methacrylate) (PHEMA) and/or poly(methyl methacrylate) (PMMA) were synthesized using living radical polymerization with a ruthenium catalyst. The polymer coatings were prepared by simple drop casting of the polymer solution onto poly(ethylene terephthalate) (PET) surfaces and then dried. Among the star polymers prepared in this study, the PHEMA star polymer (star-PHEMA) and the PHEMA/PMMA (mol. ratio of 71/29) heteroarm star polymer (star-H71M29) coatings showed the highest percentage of inhibition against platelet adhesion (78–88% relative to the non-coated PET surface) and Escherichia coli (94–97%). These coatings also showed anti-adhesion activity against platelets after incubation in Dulbecco's phosphate buffered saline or surfactant solution for 7 days. In addition, the PMMA component of the star polymers increased the scratch resistance of the coating. These results indicate that the star-polymer architecture provides high polymer chain density on PET surfaces to prevent adhesion of platelets and bacteria, as well as coating stability and physical durability to prevent exposure of bare PET surfaces. The star polymers provide a simple and effective approach to preparing anti-adhesion polymer coatings on biomedical materials against the adhesion of platelets and bacteria.
- Published
- 2014
Catalog
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