81 results on '"Akiko Yagi"'
Search Results
2. Carbon Nanobelts: Brief History and Perspective
- Author
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Daiki Imoto, Akiko Yagi, and Kenichiro Itami
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Chemistry ,QD1-999 - Published
- 2023
- Full Text
- View/download PDF
3. Synthesis, properties, and material hybridization of bare aromatic polymers enabled by dendrimer support
- Author
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Shusei Fujiki, Kazuma Amaike, Akiko Yagi, and Kenichiro Itami
- Subjects
Science - Abstract
Unsubstituted aromatic polymers are materials with multiple potential applications, but their preparation remains challenging. Here, the authors report a dendrimer-enabled synthesis of soluble bare aromatic polymers and explore their properties; these compounds can be further transformed into other materials.
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- 2022
- Full Text
- View/download PDF
4. Perfluorocycloparaphenylenes
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Hiroki Shudo, Motonobu Kuwayama, Masafumi Shimasaki, Taishi Nishihara, Youhei Takeda, Nobuhiko Mitoma, Takuya Kuwabara, Akiko Yagi, Yasutomo Segawa, and Kenichiro Itami
- Subjects
Science - Abstract
Synthetic methods for the preparation of perfluorinated aromatic compounds are desirable in materials science. Here, the authors synthesize perfluorocycloparaphenylenes, fully fluorinated carbon nanorings, through a nickel-mediated one-pot method.
- Published
- 2022
- Full Text
- View/download PDF
5. Six-fold C–H borylation of hexa-peri-hexabenzocoronene
- Author
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Mai Nagase, Kenta Kato, Akiko Yagi, Yasutomo Segawa, and Kenichiro Itami
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c–h borylation ,hexa-peri-hexabenzocoronene ,iridium catalyst ,x-ray crystallography ,Science ,Organic chemistry ,QD241-441 - Abstract
Hexa-peri-hexabenzocoronene (HBC) is known to be a poorly soluble polycyclic aromatic hydrocarbon for which direct functionalization methods have been very limited. Herein, the synthesis of hexaborylated HBC from unsubstituted HBC is described. Iridium-catalyzed six-fold C–H borylation of HBC was successfully achieved by screening solvents. The crystal structure of hexaborylated HBC was confirmed via X-ray crystallography. Optoelectronic properties of the thus-obtained hexaborylated HBC were analyzed with the support of density functional theory calculations. The spectra revealed a bathochromic shift of absorption bands compared with unsubstituted HBC under the effect of the σ-donation of boryl groups.
- Published
- 2020
- Full Text
- View/download PDF
6. Simple direct formation of self-assembled N-heterocyclic carbene monolayers on gold and their application in biosensing
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Cathleen M. Crudden, J. Hugh Horton, Mina R. Narouz, Zhijun Li, Christene A. Smith, Kim Munro, Christopher J. Baddeley, Christian R. Larrea, Benedict Drevniok, Bheeshmon Thanabalasingam, Alastair B. McLean, Olena V. Zenkina, Iraklii I. Ebralidze, Zhe She, Heinz-Bernhard Kraatz, Nicholas J. Mosey, Lisa N. Saunders, and Akiko Yagi
- Subjects
Science - Abstract
Self-assembled monolayers (SAMs) have shown tremendous number of applications but can suffer from low stability. Here, the authors report air and bench stable carbene precursors allowing facile SAM formation, and furthermore demonstrate an application in biosensing
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- 2016
- Full Text
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7. Adamantane Annulation to Arenes: A Strategy for Property Modulation of Aromatic π-Systems
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Takaku Yoshihara, Hiroki Shudo, Akiko Yagi, and Kenichiro Itami
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Colloid and Surface Chemistry ,General Chemistry ,Biochemistry ,Catalysis - Published
- 2023
8. Methylene-Bridged [6]-, [8]-, and [10]Cycloparaphenylenes: Size-Dependent Properties and Paratropic Belt Currents
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Hideya Kono, Yuanming Li, Riccardo Zanasi, Guglielmo Monaco, Francesco F. Summa, Lawrence T. Scott, Akiko Yagi, and Kenichiro Itami
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Colloid and Surface Chemistry ,General Chemistry ,Biochemistry ,Catalysis - Published
- 2023
9. Synthesis of diamondoids through hydrogenation of adamantane-annulated arenes.
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Yoshifumi Toyama, Takaku Yoshihara, Hiroki Shudo, Hideto Ito, Kenichiro Itami, and Akiko Yagi
- Abstract
Diamondoids are cage-shaped saturated hydrocarbons whose carbon scaffolds are substructures of diamond. Despite their potential application, the availability of diamondoids has been significantly limited due mainly to the difficulty in synthesis. Herein, we report a new synthetic methodology for diamondoids. It was found that adamantane-annulated arenes, which can be synthesized by our recently developed method, can be transformed to saturated hydrocarbons by catalytic hydrogenation of arene moieties. The thus-obtained hydrocarbons are unnatural diamondoids, which are otherwise difficult toobtaine. The structural analysis and DFT calculation of the reaction mechanism were also performed to initiate exploration of the untapped synthetic chemistry of diamondoids. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
10. N-doped nonalternant aromatic belt via a six-fold annulative double N-arylation
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Hiroki Sato, Rie Suizu, Tomoki Kato, Akiko Yagi, Yasutomo Segawa, Kunio Awaga, and Kenichiro Itami
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General Chemistry - Abstract
Nitrogen-doped nonalternant aromatic belt was synthesized via palladium-catalyzed six-fold annulative double N-arylation reaction. The highly symmetric structure and multistep oxidation behavior of the N-belt were confirmed.
- Published
- 2022
11. Half-substituted fluorocycloparaphenylenes with high symmetry: Synthesis, properties and derivatization to densely substituted carbon nanorings
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Hiroki Shudo, Motonobu Kuwayama, Yasutomo Segawa, Akiko Yagi, and Kenichiro Itami
- Abstract
Cycloparaphenylenes (CPPs) are ring-shaped aromatic hydrocarbons in which benzene rings are connected to each other at the para-positions. In recent years, fluorinated CPPs (FCPPs) have attracted much attention as electron-accepting CPPs as well as strained fluoroarenes. Herein, we report the synthesis, properties, and derivatization of novel FCPPs; F16[8]CPP (1) and F12[6]CPP (2), in which ortho-difluorophenylene units are circularly connected to form CPP structure. The short-step synthesis of 1 and 2 has been achieved by the strategy using macrocyclic nickel or gold complexes. Furthermore, the derivatization of 1 was successfully achieved to afford a new heteroring-containing carbon nanoring; hexadecapyrrolyl[8]cycloparaphenylene 5, where 16 pyrrole rings are densely substituted on CPP framework.
- Published
- 2023
12. Adamantane-annulation to arenes: A simple strategy for property modulation of aromatic pi-systems
- Author
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Takaku Yoshihara, Hiroki Shudo, Akiko Yagi, and Kenichiro Itami
- Abstract
Peripheral structural modifications of arenes are widely used to control or improve the optoelectronic properties, molecular assembly, and stability of aromatic pi-materials as well as to explore new functions. However, known modifications are often tedious and complex; therefore, a simple yet powerful modification strategy is needed. We discovered that annulation with a simple adamantane scaffold exerts a significant impact on the properties, alignment, and stability of aromatic pi-systems. This unprecedented adamantane annulation was achieved by a two-step transformation of metalated arenes and 4-protoadamantanone, generating a range of adamantane-annulated arenes. Analysis on structural and electronic property uncovered unique effects of the process, such as high solubility and enhanced conjugation. The oxidation of adamantane-annulated perylenes produced strikingly stable cationic species with emission extended to near-infrared region. This simple property modulation of aromatic pi-systems would not only create potentially ground-breaking oi-materials but also novel nanocarbon materials, such as diamond-graphene hybrids.
- Published
- 2023
13. Synthesis and Properties of Methylene-Bridged [6]Cyclo-2,6-naphthylene
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Kenichiro Itami, Akiko Yagi, Hideya Kono, and Nobushige Kai
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Organic Chemistry - Abstract
A novel structurally constrained nanobelt, methylene-bridged [6]cyclo-2,6-naphthylene ([6]MCN), has been synthesized by the nickel-mediated intramolecular aryl–aryl coupling of a triflated prism[6]arene. The structural and electronic properties of [6]MCN were revealed through NMR studies and photophysical measurements. In contrast to methylene-bridged [6]cycloparaphenylene, our previously synthesized benzene-based analogue, [6]MCN has a low strain energy (77.4 kcal·mol–1) and displays bright fluorescence (Φ = 0.20).
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- 2023
14. Chemical Synthesis of Carbon Nanorings and Nanobelts
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Takehisa Maekawa, Hideya Kono, Kenichiro Itami, Yuanming Li, Akiko Yagi, and Yasutomo Segawa
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Materials science ,Polymers and Plastics ,chemistry ,Chemical engineering ,Materials Science (miscellaneous) ,Materials Chemistry ,Chemical Engineering (miscellaneous) ,chemistry.chemical_element ,Carbon ,Chemical synthesis - Published
- 2021
15. Photo‐Induced Arylation of Carbazoles With Aryldiazonium Salts
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Murakami Kei, Yota Sakakibara, Kenichiro Itami, Bumpei Maeda, Genki Mori, and Akiko Yagi
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chemistry.chemical_compound ,Chemistry ,Carbazole ,Organic Chemistry ,Polymer chemistry - Published
- 2021
16. N-doped Nonalternant Aromatic Belt via a Six-fold Annulative Double N-Arylation
- Author
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Kenichiro Itami, Hiroki Sato, Rie Suizu, Tomoki Kato, Akiko Yagi, Yasutomo Segawa, and Kunio Awaga
- Abstract
Nitrogen (N)-doped nanocarbon materials have received significant attention in materials science. Therefore, the design and synthesis of new molecular scaffolds are of great importance. Herein, we report the synthesis and X-ray crystal structure of a nitrogen-inserted nonalternant aromatic belt. The palladium-catalyzed six-fold annulative double N-arylation provided an aromatic belt bearing six nitrogen atoms in one step from cyclo[6]paraphenylene-Z-ethenylene, the precursor of the (6,6)carbon nanobelt. The C3i-symmetric structure of the aromatic belt in the solid state was revealed using X-ray crystallography. The multistep chemical oxidation behavior of the belt, which was facilitated by the six p-methoxyaniline moieties, was studied, and a stable dication species was successfully isolated and identified by X-ray crystallography. The present study not only shows the unique structure and properties of the N-doped nonalternant aromatic belt but also expands the scope of accessibility of synthetically difficult belt molecules by the conventional intramolecular contraction pathway.
- Published
- 2022
17. Six-fold C–H borylation of hexa-peri-hexabenzocoronene
- Author
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Kenichiro Itami, Mai Nagase, Akiko Yagi, Kenta Kato, and Yasutomo Segawa
- Subjects
chemistry.chemical_classification ,Chemistry ,Organic Chemistry ,Hexa-peri-hexabenzocoronene ,Polycyclic aromatic hydrocarbon ,Crystal structure ,Medicinal chemistry ,Borylation ,iridium catalyst ,Full Research Paper ,lcsh:QD241-441 ,c–h borylation ,lcsh:Organic chemistry ,X-ray crystallography ,Bathochromic shift ,Density functional theory ,lcsh:Q ,hexa-peri-hexabenzocoronene ,lcsh:Science ,x-ray crystallography - Abstract
Hexa-peri-hexabenzocoronene (HBC) is known to be a poorly soluble polycyclic aromatic hydrocarbon for which direct functionalization methods have been very limited. Herein, the synthesis of hexaborylated HBC from unsubstituted HBC is described. Iridium-catalyzed six-fold C–H borylation of HBC was successfully achieved by screening solvents. The crystal structure of hexaborylated HBC was confirmed via X-ray crystallography. Optoelectronic properties of the thus-obtained hexaborylated HBC were analyzed with the support of density functional theory calculations. The spectra revealed a bathochromic shift of absorption bands compared with unsubstituted HBC under the effect of the σ-donation of boryl groups.
- Published
- 2020
18. Programmable synthesis of multiply arylated cubanes through C–H metalation and arylation
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Genki Mori, Akiko Yagi, Ryo Okude, and Kenichiro Itami
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chemistry.chemical_classification ,Chemistry ,chemistry.chemical_compound ,chemistry ,Metalation ,Cubane ,Aryl ,Regioselectivity ,General Chemistry ,Combinatorial chemistry ,Alkyl - Abstract
Cubane (C8H8), a cubic alkane, has long attracted attention owing to its unique 3D structure. In order to utilize the cubane scaffold widely in science and technology, a powerful method for synthesizing diverse cubane derivatives is required. Herein, we report the synthesis of mono-, di-, tri-, and tetra-arylated cubanes. Directed ortho-metalation with lithium base/alkyl zinc and subsequent palladium-catalyzed arylation enabled C–H metalation and arylation of cubane. This reaction allows the late-stage and regioselective installation of a wide range of aryl groups, realizing the first programmable synthesis of diverse multiply arylated cubanes., Cubane has attracted attention due to its unique 3D structure. Herein, we report the programmable synthesis of multiply arylated cubanes. The developed reaction allows the late-stage and regioselective installation of aryl groups.
- Published
- 2020
19. Alcohol-related issues among affected people
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Akiko Yagi
- Published
- 2022
20. Contributors
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Keiya Fujimori, Aya Goto, Mayumi Harigane, Arifumi Hasegawa, Kenichi Hata, Fumikazu Hayashi, Arinobu Hori, Naoko Horikoshi, Mitsuaki Hosoya, Kayoko Ishii, Tetsuo Ishikawa, Manabu Iwadate, Kenji Kamiya, Yuka Karatani, Keiko Kawashima, Tomoyuki Kobayashi, Chihaya Koriyama, Hyo Kyozuka, Masaharu Maeda, Takashi Matsuzuka, Maho Momoi, Michio Murakami, Tsuyoshi Murata, Masanori Nagao, Akihito Nakai, Hironori Nakano, Tetsuya Ohira, Hitoshi Ohto, Kanako Okazaki, Makiko Orita, Misao Ota, Kotaro Ozasa, Akira Sakai, Hideki Sato, Naoya Sekiya, Noriko Setou, Michio Shimabukuro, Hiroki Shimura, Kohta Suzuki, Kouta Suzuki, Satomi Suzuki, Satoru Suzuki, Satoshi Suzuki, Yasuyuki Taira, Noboru Takamura, Yoshitake Takebayashi, Yui Takebayashi, Masaharu Tsubokura, Yuji Tsutsui, Tokio Uchiyama, Tatsuo Ujiie, Akiko Yagi, Shun Yasuda, Seiji Yasumura, Susumu Yokoya, and Kazuki Yoshida
- Published
- 2022
21. Perfluorocycloparaphenylenes: Fully fluorinated carbon nanorings by Ni-mediated one-pot synthesis
- Author
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Youhei Takeda, Hiroki Shudo, Takuya Kuwabara, M. Kuwayama, Taishi Nishihara, Akiko Yagi, Yasutomo Segawa, Kenichiro Itami, and Masafumi Shimasaki
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Organic semiconductor ,Nickel ,Chemistry ,Intermolecular force ,One-pot synthesis ,Structural diversity ,chemistry.chemical_element ,Electrochemistry ,Phosphorescence ,Combinatorial chemistry ,Carbon - Abstract
Perfluorinated aromatic compounds, the so-called perfluoroarenes, are widely used in materials science owing to their high electron affinity and characteristic intermolecular interactions. However, methods to synthesize highly strained perfluoroarenes have remained elusive so far, which greatly limits their structural diversity. Herein, we report the synthesis and isolation of perfluorocycloparaphenylenes (PFCPPs) as a class of ring-shaped perfluoroarenes. Using macrocyclic nickel complexes, we succeeded in synthesizing PF[n]CPPs (n = 10, 12, 14, 16) in one-pot without noble metals. The molecular structures of PF[n]CPPs (n = 10, 12) were determined by X-ray crystallography to confirm their tubular alignment. Photophysical and electrochemical measurements revealed that PF[n]CPPs (n = 10, 12) exhibit wide HOMO–LUMO gaps, high electron affinity, and strong phosphorescence at low temperature. PFCPPs are not only useful as electron-accepting organic semiconductors but can also be used for accelerating the creation of topologically unique molecular nanocarbon materials.
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- 2021
22. New paradigms in molecular nanocarbon science
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Iain A. Stepek, Mai Nagase, Akiko Yagi, and Kenichiro Itami
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Organic Chemistry ,Drug Discovery ,Biochemistry - Published
- 2022
23. Synthesis of sterically hindered 4,5-diarylphenanthrenes via acid-catalyzed bisannulation of benzenediacetaldehydes with alkynes
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Kenichiro Itami, Akiko Yagi, and Yuanming Li
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chemistry.chemical_classification ,Steric effects ,010405 organic chemistry ,Stereochemistry ,Aryl ,Acetal ,Alkyne ,Regioselectivity ,General Chemistry ,010402 general chemistry ,01 natural sciences ,0104 chemical sciences ,chemistry.chemical_compound ,chemistry ,Acid catalyzed ,Phenanthrenes - Abstract
The synthesis of sterically hindered phenanthrenes via acid-catalyzed bisannulation reaction is described. Treatment of 1,4-benzenediacetaldehyde with terminal aryl alkynes in the presence of B(C6F5)3 provides 4,5-diarylphenanthrenes in good yields with excellent regioselectivity. The use of internal alkyne substrates enabled the synthesis of sterically hindered 3,4,5,6-tetrasubstituted phenanthrenes displaying augmented backbone helicity. Furthermore, 1,5-disubstituted, 1,8-disubstituted, 1,2,5,6-tetrasubstituted, and 1,2,7,8-tetrasubstituted phenanthrenes can be obtained through the reaction of alkynes with 1,3-benzenediacetaldehyde or 1,2-benzenediacetaldehyde disilyl acetal.
- Published
- 2019
24. Age factor in the fluoroquinolone susceptibility of gram-positive cocci isolates from bacterial keratitis cases between 2008 and 2016
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Koji, Ueda, Takuya, Iwasaki, Takashi, Ono, Jinhee, Lee, Ryohei, Nejima, Yosai, Mori, Yukari, Noguchi, Akiko, Yagi, and Kazunori, Miyata
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Gram-Positive Cocci ,Keratitis ,Age Factors ,Humans ,Microbial Sensitivity Tests ,Child ,Eye Infections, Bacterial ,Aged ,Anti-Bacterial Agents ,Fluoroquinolones ,Retrospective Studies - Abstract
To determine the relationship between fluoroquinolone susceptibility of gram-positive cocci (GPC) isolated from patients with bacterial keratitis and the age of the patients or the date of onset.Bacterial isolates were obtained from corneal lesions of patients with infectious keratitis treated between January 2008 and December 2016. The fluoroquinolone susceptibility of GPC was assessed, and a retrospective review of microbiological records was performed. Fluoroquinolone susceptibility was measured through broth microdilution in accordance with protocols of the Clinical and Laboratory Standards Institute. Statistical analysis was performed using a generalized estimating equation and cubic spline to determine the association between fluoroquinolone susceptibility of GPC isolated from corneal lesions and patient age.Of the 1200 bacterial isolates, 471 GPC were identified. They included Staphylococcus epidermidis (45.6%), other coagulase-negative Staphylococcus sp. (17.8%), and Staphylococcus aureus (18.3%). Levofloxacin susceptibility of GPC exhibited a negative relationship with age and had an odds ratio of 0.893 (95% confidence interval, 0.825-0.967) for every 10 years of age. A non-adjusted cubic spline curve was well correlated with year-adjusted data in a generalized additive model, and the levofloxacin susceptibility of GPC was initially stable but gradually declined after 40 years of age, before re-stabilizing again after 70 years of age.The fluoroquinolone susceptibility of GPC isolated from corneal lesions of infectious keratitis is high in children under 15 years of age and declines with an increase in age of patients using a generalized estimating equation and cubic spline.
- Published
- 2021
25. Development of potent inhibitors for strigolactone receptor DWARF 14
- Author
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Sakuya Nakamura, Ryosuke Takise, Kenichiro Itami, Masahiko Yoshimura, Akiko Yagi, Sojung F. Kim, Shinya Hagihara, Masanori Izumi, and Shuhei Kusano
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0106 biological sciences ,Plant growth ,Regulator ,Strigolactone ,Receptors, Cell Surface ,Biology ,01 natural sciences ,Catalysis ,03 medical and health sciences ,Lactones ,Plant Growth Regulators ,Materials Chemistry ,Receptor ,030304 developmental biology ,2. Zero hunger ,0303 health sciences ,fungi ,Metals and Alloys ,food and beverages ,General Chemistry ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Cell biology ,Shoot ,Ceramics and Composites ,Heterocyclic Compounds, 3-Ring ,010606 plant biology & botany ,Hormone ,Signal Transduction - Abstract
Strigolactones (SLs) are plant hormones that suppress shoot branching through perception by their receptor protein DWARF 14 (D14). The artificial regulation of SL signaling has been considered a potent agricultural technique because plant architecture is strongly related to crop yield. In this communication, we describe the development of a small-molecule D14 inhibitor that functions at sub-micromolar levels. This potent inhibitor may be a lead compound for a first-in-class plant growth regulator.
- Published
- 2020
26. A Nonalternant Aromatic Belt: Methylene-Bridged [6]Cycloparaphenylene Synthesized from Pillar[6]arene
- Author
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Kenichiro Itami, Yasutomo Segawa, Yuanming Li, and Akiko Yagi
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Materials science ,Band gap ,Supramolecular chemistry ,Pillar ,General Chemistry ,010402 general chemistry ,01 natural sciences ,Biochemistry ,Small molecule ,Catalysis ,0104 chemical sciences ,Crystallography ,chemistry.chemical_compound ,Colloid and Surface Chemistry ,chemistry ,Phenylene ,Intramolecular force ,Yield (chemistry) ,Methylene - Abstract
The synthesis, structure, and properties of methylene-bridged [6]cycloparaphenylene ([6]CPP), a non-alternant aromatic belt, are described. This belt-shaped methylene-bridged [6]CPP, in which each phenylene unit is tethered to its neighbors by methylene bridges, was constructed through six-fold intramolecular nickel-mediated aryl-aryl coupling of triflate-functionalized pillar[6]arene in 15% isolated yield. Compared with the analogous [6]CPP, the methylene bridges co-planarize neighboring paraphenylene units and enhance the degree of p-conjugation, resulting in a significant decrease in energy gap. Moreover, the incorporation of small molecules in the defined pocket of methylene-bridged [6]CPP makes it an attractive supramolecular architecture. Methylene-bridged [6]CPP is characterized by high internal strain energy reaching 110.2 kcal·mol–1, attributed to its restricted structure. This work not only exhibits an efficient strategy to construct a new family of aromatic belt, but also showcases their properties, which combine the merits of CPPs and pillararenes.
- Published
- 2020
27. Synthesis of Highly Twisted, Nonplanar Aromatic Macrocycles Enabled by an Axially Chiral 4,5-Diphenylphenanthrene Building Block
- Author
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Akiko Yagi, Kenichiro Itami, and Yuanming Li
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Crystallography ,Colloid and Surface Chemistry ,Chemistry ,Block (telecommunications) ,Twist angle ,General Chemistry ,Axial symmetry ,Biochemistry ,Catalysis - Abstract
The synthesis, structures, and properties of highly twisted, nonplanar aromatic macrocycles are described. These macrocycles with an approximately 90° twist angle were synthesized by an effective synthetic approach through a quadruple Suzuki-Miyaura coupling of 4,5-bisarylphenanthrene, a novel axially chiral nonplanar building block. By varying the cross-coupling partner as the spacer, a family of twisted macrocycles was synthesized, allowing for a systematic study of the effect of the spacer on macrocycle shape and photophysical properties. For example, a unique macrocyclic aggregation-induced emission (AIE) emitter with double tetraphenylethylene units as the spacers was readily synthesized. Furthermore, attributed to its conformationally restricted twisted structure, a 3,6-disubstituted-1,8-naphthalimide-incorporated macrocycle showed remarkable solvatofluorochromism with high fluorescence quantum yields. The excellent conformational stability of these macrocycles further enabled complete enantiomeric resolution and characterization. The racemization barrier of macrocycle was determined experimentally and supported by DFT calculations.
- Published
- 2020
28. Benzalkonium Chloride Resistance in
- Author
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Jinhee, Lee, Takuya, Iwasaki, Shinichiro, Ohtani, Hidehito, Matsui, Ryohei, Nejima, Yosai, Mori, Fumie, Kagaya, Akiko, Yagi, Akiko, Yoshimura, Hideaki, Hanaki, Makoto, Aihara, and Kazunori, Miyata
- Subjects
Travoprost ,multidrug resistance ,Staphylococcus epidermidis ,Humans ,Glaucoma ,Ophthalmic Solutions ,qacC/smr ,Benzalkonium Compounds ,benzalkonium chloride ,prostaglandin analog ,Article - Abstract
Purpose We previously reported the presence of multidrug-resistant staphylococci on the ocular surface of glaucoma patients using prostaglandin analog drops for more than 1 year. Here, we investigated the effect of benzalkonium chloride (BAC) on these multidrug-resistant staphylococci. Methods Staphylococcus epidermidis was isolated from the conjunctival sacs of 32 eyes of 32 patients comprised of 13 eyes treated with 0.005% latanoprost (Xalatan; Xa group) and 19 eyes treated with 0.004% travoprost (Travatan Z; Tz group). The minimum inhibitory concentrations (MICs) of prostaglandin analogs and BAC were measured. The presence of efflux pump genes was analyzed using polymerase chain reaction. Results No difference was found in the MIC values of prostaglandin analogs. In contrast, the MIC values of BAC were significantly higher for the isolates from the Xa group than for those from the Tz group (2.02 vs. 1.02 µg/mL; P = 0.001). One proton-motive efflux gene, qacC/smr, was detected more frequently in the Xa isolates than in the Tz isolates (P < 0.001). The prevalence of methicillin resistance was correlated with the presence of qacC/smr (P = 0.010), and the MIC of BAC was significantly correlated with the detection of qacA/B and qacC/smr sequences (P = 0.03 and P < 0.001, respectively). Conclusions The long-term use of eye drops containing BAC might select BAC-resistant S. epidermidis harboring qacC/smr. Translational Relevance These findings suggest that the long-term use of eye drops containing BAC might be inappropriate in terms of avoiding antimicrobial resistance.
- Published
- 2020
29. Armchair and Chiral Carbon Nanobelts: Scholl Reaction in Strained Nanorings
- Author
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Akiko Yagi, Yasutomo Segawa, and Kenichiro Itami
- Subjects
Materials science ,General Chemical Engineering ,Biochemistry (medical) ,chemistry.chemical_element ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Biochemistry ,0104 chemical sciences ,Scholl reaction ,Chemical engineering ,chemistry ,Asymmetric carbon ,Materials Chemistry ,Environmental Chemistry ,0210 nano-technology ,Carbon ,Nanoring - Abstract
In this issue of Chem, Cheung et al. have produced armchair (12,12) and chiral (18,12) carbon nanobelts through the Scholl reaction of carbon nanoring precursors. The design of the carbon nanorings is key to the successful synthesis of the carbon nanobelts., ファイル公開:2020-04-11
- Published
- 2019
30. Synthesis and properties of [8]-, [10]-, [12]-, and [16]cyclo-1,4-naphthylenes
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Akiko Yagi, Kenichiro Itami, Yasutomo Segawa, and Keishu Okada
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010405 organic chemistry ,Chemistry ,Aromatization ,chemistry.chemical_element ,Nanotechnology ,General Chemistry ,010402 general chemistry ,01 natural sciences ,Fluorescence spectra ,0104 chemical sciences ,Ring strain ,Crystallography ,chemistry.chemical_compound ,Nickel ,Absorption (chemistry) ,Conformational isomerism ,Naphthalene - Abstract
The synthesis and properties of various [n]cyclo-1,4-naphthylenes ([n]CNs, n = 8, 10, 12, and 16) are described. Initially, extended L-shaped units, which could be converted into quater- or quinquenaphthylenes were prepared. Nickel- or palladium-mediated couplings of these extended L-shaped units, followed by reductive aromatization of the coupling products afforded [8]-, [10]-, [12]-, and [16]CNs. The size-dependent photophysical properties of these CNs were confirmed by measuring their UV-vis absorption and fluorescence spectra. The theoretical studies supported substantial effects of the number of naphthalene rings on the structural and photophysical properties of these CNs. A kinetic study on the thermal conversion of the Cs-symmetric conformer of [10]CN into its most stable D5d-symmetric conformer indicated that ring strain affects the rotation barrier of the naphthalene rings in [10]CN.
- Published
- 2017
31. Effect of the administration period of perioperative topical levofloxacin on normal conjunctival bacterial flora
- Author
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Nobuyuki Shoji, Yukari Noguchi, Takuya Iwasaki, Akiko Yagi, Ryohei Nejima, Kazunori Miyata, Kimiya Shimizu, and Takashi Ono
- Subjects
Male ,medicine.medical_specialty ,Time Factors ,Microbiological culture ,medicine.drug_class ,medicine.medical_treatment ,Antibiotics ,Administration, Ophthalmic ,Cataract Extraction ,Levofloxacin ,Microbial Sensitivity Tests ,Perioperative Care ,03 medical and health sciences ,0302 clinical medicine ,Staphylococcus epidermidis ,Humans ,Medicine ,Prospective Studies ,030212 general & internal medicine ,Aged ,Aged, 80 and over ,Endophthalmitis ,Bacteria ,biology ,business.industry ,Perioperative ,Cataract surgery ,biology.organism_classification ,Sensory Systems ,Anti-Bacterial Agents ,Surgery ,Clinical trial ,Ophthalmology ,Anesthesia ,030221 ophthalmology & optometry ,Conjunctival sac ,Female ,Ophthalmic Solutions ,business ,Conjunctiva ,medicine.drug - Abstract
Purpose To assess the long-term and short-term effects of post-cataract surgery antibiotic therapy on the drug-resistance profile of normal conjunctival bacterial flora. Setting Miyata Eye Hospital, Miyazaki, Japan. Design Randomized prospective clinical trial. Methods Patients aged 20 years or older who had cataract surgery between May and September 2015 were given levofloxacin 1.5% ophthalmic solution for 3 days preoperatively. The patients were randomly assigned to a 1-week postoperative group or a 1-month postoperative group according to postoperative administration duration. Conjunctival sacs were scraped for bacterial culturing before administration, 1 week postoperatively, at the completion of administration, and 1, 3, and 6 months after administration completion. The bacterial culture growth and minimum inhibitory concentrations (MICs) of levofloxacin against recovered strains of Staphylococcus epidermidis were assessed. Results The study enrolled 104 patients. The MICs of levofloxacin against S epidermidis increased during levofloxacin administration compared with before administration in both groups and then declined after administration completion. However, by 3 months, the MICs in the 1-month group were approximately twice those in the 1-week group. Antibiotic susceptibility before administration, at completion of administration, and at 3 months was 73.6%, 20.2%, and 38.5%, respectively, in the 1-week group and 63.0%, 0.0%, and 19.3%, respectively, in the 1-month group. The results indicate that from completion of administration to 3 months, the susceptible strains were approximately 20% lower in the 1-month postoperative group than in the 1-week postoperative group. Conclusion Administration duration of perioperative levofloxacin 1.5% influenced the MICs and susceptibility of S epidermidis isolated from the conjunctival sac.
- Published
- 2017
32. Ni-Catalyzed α-Selective C-H Borylations of Naphthalene-Based Aromatic Compounds
- Author
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Akiko Yagi, Yasutomo Segawa, Toshiyuki Kamei, Toyoshi Shimada, and Soshi Nishino
- Subjects
chemistry.chemical_compound ,010405 organic chemistry ,Chemistry ,Organic Chemistry ,010402 general chemistry ,01 natural sciences ,Medicinal chemistry ,0104 chemical sciences ,Catalysis ,Naphthalene - Abstract
The ability of α-borylated naphthalene-based aromatic compounds is important because it provides ready access to interesting novel extended π-systems. In this report, we disclose the Ni-catalyzed α-selective C-H borylations of naphthalene-based aromatic compounds. The reaction proceeds with
- Published
- 2019
33. Branch-Selective Hydroarylation: Iodoarene–Olefin Cross-Coupling
- Author
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Akiko Yagi, Ryan A. Shenvi, Jeishla L. M. Matos, and Samantha A. Green
- Subjects
inorganic chemicals ,Olefin fiber ,010405 organic chemistry ,Chemistry ,Markovnikov's rule ,chemistry.chemical_element ,General Chemistry ,010402 general chemistry ,Ring (chemistry) ,Photochemistry ,environment and public health ,01 natural sciences ,Biochemistry ,Radical cyclization ,Catalysis ,0104 chemical sciences ,Nickel ,Colloid and Surface Chemistry ,Cobalt ,Bond cleavage - Abstract
A combination of cobalt and nickel catalytic cycles enables a highly branch-selective (Markovnikov) olefin hydroarylation. Radical cyclization and ring scission experiments are consistent with hydrogen atom transfer (HAT) generation of a carbon-centered radical that leads to engagement of a nickel cycle.
- Published
- 2016
34. A fatty acid profiling method using liquid chromatography–high resolution mass spectrometry for improvement of assisted reproductive technology
- Author
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Satoshi Miyanaga, Hirobumi Kamiya, Rojeet Shrestha, Shu-Ping Hui, Seiji Takeda, Akiko Yagi, Hitoshi Chiba, and Seiichi Kobayashi
- Subjects
Adult ,Male ,0301 basic medicine ,Reproductive Techniques, Assisted ,Clinical Biochemistry ,Biology ,Orbitrap ,Mass spectrometry ,Biochemistry ,Mass Spectrometry ,law.invention ,03 medical and health sciences ,0302 clinical medicine ,Metabolomics ,Essential fatty acid ,law ,Humans ,chemistry.chemical_classification ,030219 obstetrics & reproductive medicine ,Chromatography ,Fatty Acids ,Biochemistry (medical) ,Embryogenesis ,Fatty acid ,Embryo ,General Medicine ,Embryo, Mammalian ,Culture Media ,030104 developmental biology ,chemistry ,Docosahexaenoic acid ,embryonic structures ,Female ,Chromatography, Liquid - Abstract
Liquid chromatography-high resolution mass spectrometry (LC-HRMS) can be useful to improve in vitro fertilization (IVF). This study aims to find out an association between embryonic growth and embryonic uptake of free fatty acid (FFA) from culture media by using LC-HRMS.Embryos (n=55) from 15 couples undergoing IVF were studied. An embryo was cultivated for up to 6 days in a 20 μl-medium drop under mineral oil, and classified by a morphological grading system into the good-growth group (n=32; good quality blastocysts) and the poor-growth group (n=23; non-blastocysts). The control study was set up without embryo. Extracted ion chromatogram of FFAs was collected in negative-ion mode for each medium sample obtained after use.The percent change from control to sample in mass area for docosahexaenoic acid showed a decrease in the good-growth group than that in the poor-growth group (p0.05). Decrease in %change of docosahexaenoic acid might indicate proper embryonic growth. Similar but insignificant change was observed for other essential FFAs, but not for non-essential FFAs.The proposed metabolomic approach using LC-HRMS might be a powerful tool for non-invasive evaluation of embryonic growth.
- Published
- 2016
35. Benzalkonium Chloride Resistance in Staphylococcus epidermidis on the Ocular Surface of Glaucoma Patients Under Long-Term Administration of Eye Drops
- Author
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Ryohei Nejima, Yosai Mori, Makoto Aihara, Jinhee Lee, Akiko Yoshimura, Takuya Iwasaki, Shinichiro Ohtani, Hideaki Hanaki, Hidehito Matsui, Kazunori Miyata, Akiko Yagi, and Fumie Kagaya
- Subjects
0301 basic medicine ,biology ,Chemistry ,Biomedical Engineering ,Glaucoma ,Pharmacology ,medicine.disease ,biology.organism_classification ,Multiple drug resistance ,03 medical and health sciences ,Ophthalmology ,chemistry.chemical_compound ,Benzalkonium chloride ,030104 developmental biology ,0302 clinical medicine ,Prostaglandin analog ,Staphylococcus epidermidis ,030221 ophthalmology & optometry ,medicine ,Efflux ,Travoprost ,Latanoprost ,medicine.drug - Abstract
Purpose We previously reported the presence of multidrug-resistant staphylococci on the ocular surface of glaucoma patients using prostaglandin analog drops for more than 1 year. Here, we investigated the effect of benzalkonium chloride (BAC) on these multidrug-resistant staphylococci. Methods Staphylococcus epidermidis was isolated from the conjunctival sacs of 32 eyes of 32 patients comprised of 13 eyes treated with 0.005% latanoprost (Xalatan; Xa group) and 19 eyes treated with 0.004% travoprost (Travatan Z; Tz group). The minimum inhibitory concentrations (MICs) of prostaglandin analogs and BAC were measured. The presence of efflux pump genes was analyzed using polymerase chain reaction. Results No difference was found in the MIC values of prostaglandin analogs. In contrast, the MIC values of BAC were significantly higher for the isolates from the Xa group than for those from the Tz group (2.02 vs. 1.02 µg/mL; P = 0.001). One proton-motive efflux gene, qacC/smr, was detected more frequently in the Xa isolates than in the Tz isolates (P < 0.001). The prevalence of methicillin resistance was correlated with the presence of qacC/smr (P = 0.010), and the MIC of BAC was significantly correlated with the detection of qacA/B and qacC/smr sequences (P = 0.03 and P < 0.001, respectively). Conclusions The long-term use of eye drops containing BAC might select BAC-resistant S. epidermidis harboring qacC/smr. Translational Relevance These findings suggest that the long-term use of eye drops containing BAC might be inappropriate in terms of avoiding antimicrobial resistance.
- Published
- 2020
36. Psychometric evaluation of the simplified Japanese version of the Athens Insomnia Scale: The Fukushima Health Management Survey
- Author
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Yuriko Suzuki, Mayumi Harigane, Yoshitake Takebayashi, Akiko Yagi, Tetsuya Ohira, Masaharu Maeda, Hirooki Yabe, Seiji Yasumura, Hajime Iwasa, and Wen Zhang
- Subjects
Male ,Insomnia ,Psychometrics ,Cognitive Neuroscience ,03 medical and health sciences ,Behavioral Neuroscience ,0302 clinical medicine ,Japan ,Cronbach's alpha ,Sleep Initiation and Maintenance Disorders ,medicine ,Humans ,Measurement invariance ,Athens insomnia scale ,Regular Research Paper ,scale development ,Health Maintenance Organizations ,Reproducibility of Results ,General Medicine ,Middle Aged ,Mental illness ,medicine.disease ,community dwellers ,Health Surveys ,Confirmatory factor analysis ,Test (assessment) ,experiencing disaster ,030228 respiratory system ,Scale (social sciences) ,Female ,medicine.symptom ,Psychology ,030217 neurology & neurosurgery ,Clinical psychology - Abstract
We investigated the psychometric properties of the simplified Japanese version of the Athens Insomnia Scale (AIS‐SJ) using baseline data from the Fukushima Health Management Survey. Data from 22 878 men and 27 669 women aged 16 years and older were analysed (M age = 52.9 ± 18.6). Participants lived in the Fukushima evacuation zone and experienced the Great East Japan Earthquake. The AIS‐SJ was used to assess participants’ insomnia symptoms, and its validity was examined by administering the Kessler 6‐item Psychological Distress Scale (K6) and assessing education, self‐rated health and disaster‐related experiences. A confirmatory factor analysis revealed that the two‐factor model was a better fit than the one‐factor model. The AIS‐SJ and its subscales had acceptable reliability (Cronbach's alpha, 0.81). Test of measurement invariance confirmed strict invariance across groups for the participants’ characteristics of gender and mental illness history, but not for participants’ age. AIS‐SJ scores exhibited a near‐normal distribution (skewness, 0.45; kurtosis, −0.89). There were significant age differences only among women, and gender differences in AIS‐SJ scores with small effect sizes. The AIS‐SJ scores had weak‐to‐moderate correlations with mental illness history, bereavement, experiencing the tsunami, experiencing the nuclear power plant incident, housing damage and losing one's job (polyserial correlations, 0.36, 0.17, 0.13, 0.18, 0.13, and 0.15, respectively), and strong correlations with self‐rated health (polyserial correlation, 0.51), psychological distress (r s, 0.60) and post‐traumatic stress disorder (r s, 0.60). The AIS‐SJ is a useful instrument for assessing community dwellers’ insomnia symptoms.
- Published
- 2018
37. Physical and mental development of children after
- Author
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Yukiko, Nakajo, Noritaka, Fukunaga, Kohei, Fuchinoue, Akiko, Yagi, Setsuyo, Chiba, Miho, Takeda, Koichi, Kyono, and Yasuhisa, Araki
- Subjects
animal structures ,Pregnancy ,embryonic structures ,reproductive and urinary physiology - Abstract
Objective: To evaluate the physical and mental development of children after in vitro fertilization (IVF) and frozen embryo transfer (FET).
- Published
- 2018
38. Interaction Between Pilocarpine and Ripasudil on Intraocular Pressure, Pupil Diameter, and the Aqueous-Outflow Pathway
- Author
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Makoto Aihara, Tomokazu Fujimoto, Yuka Araki, Takatoshi Uchida, Kazunori Miyata, Reiko Yamagishi-Kimura, Akiko Yagi, Megumi Honjo, Hidenobu Tanihara, Takashi Komizo, Jinhee Lee, Junko Nishida, Toshihiro Inoue, and Takashi Ono
- Subjects
0301 basic medicine ,Miosis ,Adult ,Male ,Myosin light-chain kinase ,Contraction (grammar) ,Myosin Light Chains ,genetic structures ,Blotting, Western ,Administration, Ophthalmic ,Muscarinic Agonists ,Aqueous Humor ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Trabecular Meshwork ,medicine ,Electric Impedance ,Animals ,Humans ,Drug Interactions ,Enzyme Inhibitors ,Phosphorylation ,Rho-associated protein kinase ,Intraocular Pressure ,Sulfonamides ,rho-Associated Kinases ,Chemistry ,Pilocarpine ,Pupil ,Middle Aged ,Isoquinolines ,eye diseases ,Healthy Volunteers ,030104 developmental biology ,Ciliary muscle ,medicine.anatomical_structure ,Actin Depolymerizing Factors ,030221 ophthalmology & optometry ,Biophysics ,Macaca ,Female ,sense organs ,Ripasudil ,Trabecular meshwork ,medicine.symptom ,Ophthalmic Solutions ,medicine.drug - Abstract
Purpose To explore interactions between pilocarpine and the ROCK inhibitor, ripasudil, on IOP and pupil diameter in human eyes, and morphological and functional changes in outflow tissues in vitro. Methods IOP and pupil diameter were measured after pilocarpine and/or ripasudil, which were topically applied in healthy subjects. Human trabecular meshwork (HTM) cells were used in a gel contraction assay, for the evaluation of phosphorylation of myosin light chain and cofilin, and immunostaining for cytoskeletal proteins. Porcine ciliary muscle (CM) was used in a CM contraction assay. The permeability of human Schlemm's canal endothelial (SCE) cells was evaluated by measuring transendothelial electrical resistance and fluorescein permeability. Results Both pilocarpine and ripasudil significantly reduced IOP in human eyes, but pilocarpine interfered with ripasudil-induced IOP reduction when concomitantly introduced. Ripasudil significantly inhibited gel contraction, TGFβ2-induced stress fiber formation, α-smooth muscle actin expression, and phosphorylation of both myosin light chain and cofilin in HTM cells. Pilocarpine reduced these effects, significantly inhibited the ripasudil-induced HTM cell responses to TGFβ2 stimulation, and increased the permeability in SCE cells. In CM, ripasudil inhibited pilocarpine-stimulated contraction, but ripasudil did not have significant effects on pilocarpine-induced miosis. Conclusions Pilocarpine interfered with the direct effects of ROCK inhibitor on the conventional outflow pathway leading to IOP reduction and cytoskeletal changes in trabecular meshwork cells, but did not affect the relaxation effect of the ROCK inhibitor. It is therefore necessary to consider possible interference between these two drugs, which both affect the conventional outflow.
- Published
- 2018
39. 3. Chemical Synthesis of Cycloparaphenylenes
- Author
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Yasutomo Segawa, Akiko Yagi, and Kenichiro Itami
- Published
- 2017
40. Chemical Synthesis of Cycloparaphenylenes
- Author
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Kenichiro Itami, Yasutomo Segawa, and Akiko Yagi
- Subjects
010405 organic chemistry ,General Physics and Astronomy ,General Materials Science ,Nanotechnology ,General Chemistry ,010402 general chemistry ,01 natural sciences ,Chemical synthesis ,0104 chemical sciences - Abstract
Cycloparaphenylenes and analogues thereof are substances having excellent structural and electronic properties due to radial π-conjugation modes and porous structures. Since they are partial structures of carbon nanotubes, they have also attracted attention as a template for carbon nanotube synthesis. In this chapter, we introduce a series of research on the synthesis of cycloparaphenylenes and their analogues.
- Published
- 2017
41. Changes in drinking behavior among evacuees after the Fukushima Daiichi Nuclear Power Plant accident : the Fukushima Health Management Survey.
- Author
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Akiko Yagi, Masaharu Maeda, Yuriko Suzuki, Hirooki Yabe, Seiji Yasumura, Shinichi Niwa, Tetsuya Ohira, Akira Ohtsuru, Hirobumi Mashiko, Mayumi Harigane, Hironori Nakano, and Masafumi Abe
- Subjects
DRINKING behavior ,NUCLEAR power plant accidents ,CROSS-sectional method ,ALCOHOL drinking ,INSOMNIA - Abstract
Introduction Traumatic experiences and disordered sleep are strongly associated with drinking problems. We examined the effects of experiencing the Great East Japan Earthquake and subsequent nuclear power plant accident, and of sleep problems, on behavioral changes observed in nondrinkers. Methods This study examined cross-sectional data from the Mental Health and Lifestyle Survey conducted among residents in restricted areas of Fukushima in 2012. Participants were 21,454 evacuees aged 20 years or older at the time of disaster. People who did not drink before the disaster but became drinkers afterwards were compared with the rest of the cohort. We analyzed the association between behavioral changes in non-drinkers and potentially predictive variables, using logistic regression. Results The behavioral change of non-drinkers becoming drinkers (n=2,148) was significantly related to being male (OR=1.93, 95% CI : 1.74-2.15), being younger (21-49 yrs, OR=1.85, 95% CI : 1.60-2.13), having less educational attainment (up to high school graduate, OR=1.21, 95% CI : 1.09- 1.35), smoking (OR=1.22, 95% CI : 1.08-1.38), losing family or relatives (OR=1.21, 95% CI : 1.07- 1.37), change in employment (OR=1.19, 95% CI : 1.07-1.32), having severe sleep problems as measured by a Japanese version of the Athens Insomnia Scale (3-8, OR=1.45, 95% CI : 1.30-1.62), and severity of traumatic symptoms as measured by the PTSD Checklist Stressor-Specific (PCL-S) score (<44, OR=1.33, 95% CI : 1.17-1.51). Conclusion Having sleep problems and having more severe traumatic symptoms are significantly related to non-drinkers becoming drinkers. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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42. A Nonalternant Aromatic Belt: Methylene-Bridged [6]Cycloparaphenylene Synthesized from Pillar[6]arene.
- Author
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Yuanming Li, Yasutomo Segawa, Akiko Yagi, and Kenichiro Itami
- Published
- 2020
- Full Text
- View/download PDF
43. A Theoretical Study on the Strain Energy of Carbon Nanobelts
- Author
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Kenichiro Itami, Akiko Yagi, Hideto Ito, and Yasutomo Segawa
- Subjects
010405 organic chemistry ,Chemistry ,Organic Chemistry ,chemistry.chemical_element ,Nanotechnology ,Carbon nanotube ,010402 general chemistry ,01 natural sciences ,Biochemistry ,0104 chemical sciences ,law.invention ,Strain energy ,Chemical engineering ,law ,Molecule ,Physical and Theoretical Chemistry ,Carbon - Abstract
A theoretical study on the strain energy of carbon nanobelts, i.e. the belt-shaped molecules representing the sidewall structures of carbon nanotubes, is reported. The strain energy of carbon nanobelts with chiral indices (n,n), (n,0), and (n,m) was determined without considering hypothetical homodesmotic reactions. The calculated difference between the strain energy of carbon nanobelts and their possible precursors is expected to be of great utility for future synthetic purposes.
- Published
- 2016
44. Catalytic Activation of Carbon-Carbon Bond in Cyclopentanone Derivatives
- Author
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Akiko Yagi
- Subjects
chemistry.chemical_classification ,chemistry.chemical_compound ,Chemistry ,Carbon–carbon bond ,Organic Chemistry ,Organic chemistry ,Photochemistry ,Cyclopentanone ,Catalysis - Published
- 2017
45. The role of sleep disturbance and depression in patients with type 2 diabetes
- Author
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Satoshi Ugi, Yoshihiko Nishio, Naoto Yamada, Akiko Yagi, Masako Okawa, Hiroshi Maegawa, Hiromichi Kawai, Makoto Imai, Atsunori Kashiwagi, and Takashi Uzu
- Subjects
Sleep disorder ,medicine.medical_specialty ,business.industry ,Endocrinology, Diabetes and Metabolism ,Insulin ,medicine.medical_treatment ,Type 2 diabetes ,medicine.disease ,humanities ,Pittsburgh Sleep Quality Index ,Quality of life ,Internal medicine ,Diabetes mellitus ,Internal Medicine ,Physical therapy ,Medicine ,Risk factor ,business ,Depression (differential diagnoses) - Abstract
The importance of sleep disturbance and depression in patients with type 2 diabetes is unclear. Our objective was to evaluate their effects on the quality of life (QOL) of patients with type 2 diabetes. For the study, 270 patients were recruited from the Shiga Prospective Observational Follow-up Study for Diabetic Complications. Depressive symptoms, sleep disturbance, and QOL were assessed by use of the Zung Self-Rating Depression Scale (SDS), the Pittsburgh Sleep Quality Index (PSQI), and SF-8, respectively, after evaluation of their metabolic control and complications. Furthermore, 141 patients were recruited to repeat the same study after 6–12 (mean 7.3) months. Significant correlations were found among sleep disturbance, depression, and QOL in patients with type 2 diabetes. Patients undergoing insulin therapy had significantly higher SDS scores, meaning more depressive symptoms, than those not undergoing insulin therapy. Patients with painful neuropathy had higher PSQI and SDS scores and lower physical component of the QOL score than patients without painful neuropathy. In the follow-up observation it was found that the presence of neuropathy and elevated HbA1c level were predictors of increasing PSQI score and SDS score, respectively. It was found that the presence of painful neuropathy was a risk factor for sleep disturbance for type 2 diabetic patients. Sleep disturbance and depressive symptoms correlated significantly with the QOL scores of patients with type 2 diabetes, suggesting the importance of these indices for better management of diabetic patients.
- Published
- 2011
46. Synthesis and properties of cycloparaphenylene-2,7-pyrenylene: a pyrene-containing carbon nanoring
- Author
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Yasutomo Segawa, Kenichiro Itami, Akiko Yagi, and Gandikota Venkataramana
- Subjects
Cyclohexane ,chemistry.chemical_element ,Photochemistry ,Catalysis ,chemistry.chemical_compound ,Nickel ,Polymer chemistry ,Materials Chemistry ,Electronic properties ,Pyrenes ,Metals and Alloys ,Aromatization ,General Chemistry ,Carbon ,Nanostructures ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,chemistry ,Ceramics and Composites ,Quantum Theory ,Pyrene ,Absorption (chemistry) ,Palladium ,Nanoring - Abstract
The first synthesis of a pyrene-containing carbon nanoring, cyclo[12]paraphenylene[2]-2,7-pyrenylene ([12,2]CPPyr), is described. Through a sequence of stepwise macrocyclization using Pd and Ni catalysts followed by aromatization of L-shaped cyclohexane units afforded a [12,2]CPPyr in five steps from commercially available compounds. The UV-vis absorption and fluorescence spectra as well as TD-DFT calculations clarified the unique photophysical and electronic properties of the [12,2]CPPyr.
- Published
- 2014
47. Report on Fukushima Counseling Support Professional Team: Interdisciplinary Team Approach for Psychosocial Care of Evacuees
- Author
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Akiko Yagi
- Subjects
Social work ,business.industry ,media_common.quotation_subject ,Sorrow ,Certification ,Long-term care ,Dignity ,Nursing ,Intervention (counseling) ,Medicine ,Psychological resilience ,business ,Psychosocial ,media_common - Abstract
The Great East Japan Earthquake brought enormous pain and sorrow, but it tested resilience and tenacity among the people in Japan at the same time. In Fukushima, certified social workers, care managers, medical social workers, physical therapists, psychiatric social workers, and occupational therapists promptly assembled right after the disaster to help people at the evacuation centers and the affected areas maintain their dignity and prevent deterioration of their health and functioning. The unique interdisciplinary Counseling Support Professional Team (“the Team”) formed in Japan gives inspiration to all helping professionals about what can be done during the disaster. In this article, two themes are presented that may facilitate a successful intervention relative to the psychosocial aspect of evacuees in order to help readers prepare for similar situations. The first theme maps out the conditions that are unique to Fukushima, and the other explores what has been learned from the experience.
- Published
- 2015
48. Design and Synthesis of Carbon Nanotube Segments
- Author
-
Yasutomo Segawa, Kenichiro Itami, Akiko Yagi, and Katsuma Matsui
- Subjects
Materials science ,010405 organic chemistry ,Nanotechnology ,General Chemistry ,Carbon nanotube ,010402 general chemistry ,01 natural sciences ,Catalysis ,0104 chemical sciences ,law.invention ,chemistry.chemical_compound ,chemistry ,law ,Organic synthesis ,Chirality (chemistry) - Abstract
The selective and predictable synthesis of structurally uniform carbon nanotubes (CNTs) represents a long-standing goal in both nanocarbon science and synthetic organic chemistry. This Review focuses on synthetic studies toward the controlled synthesis of CNTs with single chirality through the organic synthesis of CNT segments and the organic template assisted growth of CNTs.
- Published
- 2015
49. Identification of molecular species of oxidized triglyceride in plasma and its distribution in lipoproteins
- Author
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Hitoshi Chiba, Seiji Takeda, Hirotoshi Fuda, Rojeet Shrestha, Akiko Yagi, Yuji Takahashi, Shu-Ping Hui, and Yusuke Miura
- Subjects
Adult ,Male ,Very low-density lipoprotein ,Clinical Biochemistry ,High-performance liquid chromatography ,Mass Spectrometry ,Young Adult ,chemistry.chemical_compound ,Liquid chromatography–mass spectrometry ,Cholesterylester transfer protein ,Humans ,Chromatography, High Pressure Liquid ,Triglycerides ,Intermediate-density lipoprotein ,Triglyceride ,biology ,Biochemistry (medical) ,General Medicine ,Healthy Volunteers ,Lipoproteins, LDL ,Specimen collection ,Biochemistry ,chemistry ,biology.protein ,Female ,lipids (amino acids, peptides, and proteins) ,Lipoproteins, HDL ,Oxidation-Reduction ,Lipoprotein - Abstract
BACKGROUND The role of triglycerides carried in the triglyceride-rich lipoproteins (TRL) in the progression of atherosclerosis is uncertain. Identification of oxidized triglycerides and its possible association with atherosclerosis were largely ignored. Here we applied mass spectrometric approach to detect and identify triglyceride hydroperoxides (TGOOH) in human plasma and lipoproteins. METHODS EDTA plasma was collected from healthy human volunteers (n=9) after 14-16 h of fasting. Very low-density lipoprotein (VLDL) (d
- Published
- 2015
50. Physical and mental development of children afterin vitrofertilization and embryo transfer
- Author
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Koichi Kyono, Miho Takeda, Yukiko Nakajo, Akiko Yagi, Setsuyo Chiba, Yasuhisa Araki, Kohei Fuchinoue, and Noritaka Fukunaga
- Subjects
Response rate (survey) ,Mental development ,medicine.medical_specialty ,Assisted reproductive technology ,In vitro fertilisation ,Singleton ,business.industry ,Obstetrics ,medicine.medical_treatment ,Reproductive medicine ,Cell Biology ,Embryo transfer ,Intracytoplasmic sperm injection ,Reproductive Medicine ,medicine ,business ,reproductive and urinary physiology - Abstract
To evaluate the physical and mental development of children after in vitro fertilization (IVF) and frozen embryo transfer (FET). Between July 1995 and November 2003, 506 patients delivered 658 babies after IVF and ET treatment at our clinic (intracytoplasmic sperm injection (ICSI), 418; conventional IVF, (C-IVF) 125; FET, 115). A survey of the physical and mental developmental of the children was conducted by mailing questionnaires to parents. Comparisons were made between three treatment procedures, and development of singleton, twin and triplet delivery. The response rate was 73.4% (483/658) for 324 children born after ICSI, 78 born after C-IVF, and 81 born after FET. The height and weight of assisted reproductive technology (ART) children at birth were significantly lower than that of naturally conceived babies (ART children: natural delivery; 46.8 cm, 49.0 cm and 2524 g, 3040 g, respectively). However, there was no significant difference between the singletons alone and naturally conceived children irrespective of the ART method. In addition, mental development was the same between singletons and naturally conceived children. The ART group tended to delay body development such as ‘holding their head uprs, ‘sitting up’, ‘crawl’ to moving growth in multiple births. The physical and mental development of twins or triplets was significantly more delayed than that of naturally conceived babies, but had improved to a similar extent of the singletons after the age of 6 months.
- Published
- 2004
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