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  1. Article ; Online: Weak O

    Yamasaki, Sotaro / Shoji, Mitsuo / Kayanuma, Megumi / Sladek, Vladimir / Inaoka, Daniel Ken / Matsuo, Yuichi / Shiba, Tomoo / Young, Luke / Moore, Anthony L / Kita, Kiyoshi / Shigeta, Yasuteru

    Biochimica et biophysica acta. Bioenergetics

    2020  Volume 1862, Issue 4, Page(s) 148356

    Abstract: ... of O ...

    Abstract Alternative oxidase (AOX) catalyzes the four-electron reduction of dioxygen to water as an additional terminal oxidase, and the catalytic reaction is critical for the parasite to survive in its bloodstream form. Recently, the X-ray crystal structure of trypanosome alternative oxidase (TAO) complexed with ferulenol was reported and the molecular structure of the non-heme diiron center was determined. The binding of O
    MeSH term(s) Cryptosporidium parvum/chemistry ; Hydrogen Peroxide/chemistry ; Mitochondrial Proteins/chemistry ; Oxidoreductases/chemistry ; Oxygen/chemistry ; Plant Proteins/chemistry ; Protozoan Proteins/chemistry ; Trypanosoma/chemistry
    Chemical Substances Mitochondrial Proteins ; Plant Proteins ; Protozoan Proteins ; Hydrogen Peroxide (BBX060AN9V) ; Oxidoreductases (EC 1.-) ; alternative oxidase (EC 1.-) ; Oxygen (S88TT14065)
    Language English
    Publishing date 2020-12-29
    Publishing country Netherlands
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 60-7
    ISSN 1879-2650 ; 1879-2596 ; 1879-260X ; 1872-8006 ; 1879-2642 ; 1879-2618 ; 0006-3002 ; 0005-2728 ; 0005-2736 ; 0304-4165 ; 0167-4838 ; 1388-1981 ; 0167-4889 ; 0167-4781 ; 0304-419X ; 1570-9639 ; 0925-4439 ; 1874-9399
    ISSN (online) 1879-2650 ; 1879-2596 ; 1879-260X ; 1872-8006 ; 1879-2642 ; 1879-2618
    ISSN 0006-3002 ; 0005-2728 ; 0005-2736 ; 0304-4165 ; 0167-4838 ; 1388-1981 ; 0167-4889 ; 0167-4781 ; 0304-419X ; 1570-9639 ; 0925-4439 ; 1874-9399
    DOI 10.1016/j.bbabio.2020.148356
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Oligomerization mechanism of epigallocatechin-3-O-gallate during autoxidation.

    Matsuo, Yosuke / Katayama, Kohei / Yamashita, Takako / Saito, Yoshinori / Tanaka, Takashi

    Food chemistry

    2024  Volume 449, Page(s) 139186

    Abstract: ... the autoxidation of (-)-epigallocatechin-3-O-gallate (1) was examined. The autoxidation with β-cyclodextrin ...

    Abstract The autoxidation of tea catechins by dissolved oxygen proceeds in pH-neutral aqueous solutions, and the major products are oligomers. However, the reaction mechanisms have not been clarified. In this study, the autoxidation of (-)-epigallocatechin-3-O-gallate (1) was examined. The autoxidation with β-cyclodextrin, which includes the A-ring of 1, significantly suppressed oligomer production and increased the formation of products generated by the oxidative cleavage of the B-ring, indicating the participation of the A-ring in the oligomerization. Further, the autoxidation of 1 in the presence of phloroglucinol, a mimic of the catechin A-ring, yielded products via the nucleophilic addition of phloroglucinol to the B-ring quinone of 1. These results indicated that the oxidative A-B ring couplings accounted for the major oligomerization mechanism.
    MeSH term(s) Catechin/chemistry ; Catechin/analogs & derivatives ; Oxidation-Reduction ; Molecular Structure ; Tea/chemistry
    Chemical Substances Catechin (8R1V1STN48) ; epigallocatechin gallate (BQM438CTEL) ; Tea
    Language English
    Publishing date 2024-03-30
    Publishing country England
    Document type Journal Article
    ZDB-ID 243123-3
    ISSN 1873-7072 ; 0308-8146
    ISSN (online) 1873-7072
    ISSN 0308-8146
    DOI 10.1016/j.foodchem.2024.139186
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article: Carbonylation of o-phenylenediamines with CO2 to 2-benzimidazolones catalyzed by alumina

    Matsuo, Hideaki / Choi, Jun-Chul / Fujitani, Tadahiro / Fujita, Ken-ichi

    Tetrahedron letters. 2022 Apr. 27, v. 96

    2022  

    Abstract: ... in the environment. We report here that alumina (Al₂O₃) can by itself catalyze the carbonylation of o ...

    Abstract Biological carbon fixation can convert carbon dioxide (CO₂) into chemicals with a variety of uses, and has thus attracted considerable attention, as CO₂ is nonhazardous, inflammable and plentiful in the environment. We report here that alumina (Al₂O₃) can by itself catalyze the carbonylation of o-phenylenediamines with CO₂ to produce 2-benzimidazolones. Such alumina-catalyzed carbonylation with CO₂ is applicable to various diamine derivatives to provide the corresponding cyclic ureas. Following the reaction, the alumina catalyst is also advantageous in that it can be filtered, accumulated, and reused.
    Keywords aluminum oxide ; carbon dioxide ; carbon dioxide fixation ; catalysts ; catalytic activity
    Language English
    Dates of publication 2022-0427
    Publishing place Elsevier Ltd
    Document type Article
    ZDB-ID 204287-3
    ISSN 1873-3581 ; 0040-4039
    ISSN (online) 1873-3581
    ISSN 0040-4039
    DOI 10.1016/j.tetlet.2022.153772
    Database NAL-Catalogue (AGRICOLA)

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  4. Article ; Online: Site-Selective Wettability Control of Honeycomb Films by UV-O

    Yabu, Hiroshi / Matsui, Jun / Matsuo, Yasutaka

    Langmuir : the ACS journal of surfaces and colloids

    2020  Volume 36, Issue 40, Page(s) 12023–12029

    Abstract: ... organized polymer honeycomb films to control surface wettability by simple sol-gel coating and UV-O ...

    Abstract Wettability control of porous materials is significant in lateral flow immunoassay, microfluidic systems, microdroplet manipulation, and so on. In this report, formation of metal oxide layers on self-organized polymer honeycomb films to control surface wettability by simple sol-gel coating and UV-O
    Language English
    Publishing date 2020-09-28
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2005937-1
    ISSN 1520-5827 ; 0743-7463
    ISSN (online) 1520-5827
    ISSN 0743-7463
    DOI 10.1021/acs.langmuir.0c02401
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Effects of 6-O-α-maltosyl-β cyclodextrin on lipid metabolism in Npc1-deficient Chinese hamster ovary cells.

    Okada, By Yasuyo / Kuroiwa, Sayako / Noi, Ayaka / Tanaka, Ayaka / Nishikawa, Junichi / Kondo, Yuki / Ishitsuka, Yoichi / Irie, Tetsumi / Higaki, Katsumi / Matsuo, Muneaki / Ichikawa, Atsushi

    Molecular genetics and metabolism

    2022  Volume 137, Issue 3, Page(s) 239–248

    Abstract: ... determines the effects of 6-O-α-maltosyl-β cyclodextrin (Mal-βCD) on lipid levels and synthesis in Npc1 ...

    Abstract Niemann-Pick disease Type C (NPC) is a lysosomal storage disorder caused by mutation of the NPC1/NPC2 genes, which ultimately results in the accumulation of unesterified cholesterol (UEC) in lysosomes, thereby inducing symptoms such as progressive neurodegeneration and hepatosplenomegaly. This study determines the effects of 6-O-α-maltosyl-β cyclodextrin (Mal-βCD) on lipid levels and synthesis in Npc1-deficient (Npc1-KO cells) and vehicle CHO cells. Compared to vehicle cells, Npc1-KO cells exhibited high level of UEC, and low levels of esterified cholesterols (ECs) and long-chain fatty acids (LCFAs). The difference in lipid levels between Npc1-KO and CHO cells was largely ameliorated by Mal-βCD administration. Moreover, the effects of Mal-βCD were reproduced in the lysosomes prepared from Npc1-KO cells. Stable isotope tracer analysis with extracellular addition of D4-deuterated palmitic acid (D4-PA) to Npc1-KO cells increased the synthesis of D4-deuterated LCFAs (D4-LCFAs) and D4-deuterated ECs (D4-ECs) in a Mal-βCD-dependent manner. Simultaneous addition of D6-deuterated UEC (D6-UEC) and D4-PA promoted the Mal-βCD-dependent synthesis of D6-/D4-ECs, consisting of D6-UEC and D4-PA, D4-deuterated stearic acid, or D4-deuterated myristic acid, in Npc1-KO cells. These results suggest that Mal-βCD helps to maintain normal lipid metabolism by restoring balance among UEC, ECs, and LCFAs through acting on behalf of NPC1 in Npc1-KO cells and may therefore be useful in designing effective therapies for NPC.
    MeSH term(s) Animals ; Cricetinae ; Humans ; Niemann-Pick Disease, Type C/genetics ; Niemann-Pick Disease, Type C/metabolism ; Cricetulus ; CHO Cells ; Lipid Metabolism ; beta-Cyclodextrins/pharmacology ; Cholesterol/metabolism ; Niemann-Pick C1 Protein/metabolism
    Chemical Substances beta-Cyclodextrins ; Cholesterol (97C5T2UQ7J) ; NPC1 protein, human ; Niemann-Pick C1 Protein
    Language English
    Publishing date 2022-09-23
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1418518-0
    ISSN 1096-7206 ; 1096-7192
    ISSN (online) 1096-7206
    ISSN 1096-7192
    DOI 10.1016/j.ymgme.2022.09.007
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: New degradation mechanism of black tea pigment theaflavin involving condensation with epigallocatechin-3-O-gallate.

    Tanaka, Takashi / Yasumatsu, Miho / Hirotani, Mayu / Matsuo, Yosuke / Li, Na / Zhu, Hong-Tao / Saito, Yoshinori / Ishimaru, Kanji / Zhang, Ying-Jun

    Food chemistry

    2021  Volume 370, Page(s) 131326

    Abstract: ... with epigallocatechin-3-O-gallate (EGCg), which is the most abundant polyphenol in tea leaves. In citrate-phosphate ...

    Abstract Theanaphthoquinone (TNQ) is the initial and main oxidation product of theaflavin, a representative black tea pigment. Nevertheless, TNQ is virtually undetected in the high-performance liquid chromatography analysis of black tea leaves using photodiode array detection. To elucidate the degradation mechanism of theaflavin in the black tea production process, this study investigated the reaction of TNQ with epigallocatechin-3-O-gallate (EGCg), which is the most abundant polyphenol in tea leaves. In citrate-phosphate buffer solution at pH 6 and room temperature, TNQ reacted nonenzymatically with EGCg to afford three products, whose structures were determined on the basis of spectroscopic data. The results indicated that the double bond of the ortho-naphthoquinone moiety in TNQ reacted with the autoxidation product of EGCg. This study demonstrates novel reactions occurring in the process of theaflavin degradation, which might be involved in the formation of thearubigins, the major black tea pigments composing oligomeric catechin oxidation products.
    MeSH term(s) Biflavonoids ; Catechin/analogs & derivatives ; Tea
    Chemical Substances Biflavonoids ; Tea ; theaflavin (1IA46M0D13) ; Catechin (8R1V1STN48) ; epigallocatechin gallate (BQM438CTEL)
    Language English
    Publishing date 2021-10-06
    Publishing country England
    Document type Journal Article
    ZDB-ID 243123-3
    ISSN 1873-7072 ; 0308-8146
    ISSN (online) 1873-7072
    ISSN 0308-8146
    DOI 10.1016/j.foodchem.2021.131326
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: A novel fiber-optic based 0.014″ pressure wire: Designs of the OptoWire™, development phases, and the O

    Ulacia, Paola / Rimac, Goran / Lalancette, Sébastien / Belleville, Claude / Mongrain, Rosaire / Plante, Sylvain / Rusza, Zoltan / Matsuo, Hitoshi / Bertrand, Olivier F

    Catheterization and cardiovascular interventions : official journal of the Society for Cardiac Angiography & Interventions

    2020  

    Abstract: ... evolution of a nitinol fiber-optic pressure wire and to summarize the First-in-Man (FIM) O: Background ... In the First-in-Man O: Conclusion: The novel 0.014" fiber-optic OptoWire™ provides superior wire handling ...

    Abstract Objectives: To review the technical limitations of available pressure-wires, present the design evolution of a nitinol fiber-optic pressure wire and to summarize the First-in-Man (FIM) O
    Background: Despite increasing use of physiology assessment of coronary lesions, several technical limitations persist. We present technical details, design evolution and early clinical results with a novel 0.014" nitinol fiber-optic based pressure-wire.
    Methods and results: The 0.014' OptoWire™ (Opsens Medical, Quebec, Canada) was designed to combine improved handling properties compared to standard pressure-wires and to offer extremely reliable pressure recording and transmission due to fiber-optic properties compared to piezo-electric sensors and electrical wires. In vitro assessment showed that OptoWire™ steerability, pushability and torquability properties were closer to regular PCI wires than standard electrical pressure wires. In the First-in-Man O
    Conclusion: The novel 0.014" fiber-optic OptoWire™ provides superior wire handling with reduced risk of pressure drift allowing reliable pre- and post-PCI physiology assessment.
    Language English
    Publishing date 2020-10-14
    Publishing country United States
    Document type Journal Article
    ZDB-ID 1459995-8
    ISSN 1522-726X ; 1522-1946
    ISSN (online) 1522-726X
    ISSN 1522-1946
    DOI 10.1002/ccd.29321
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  8. Article: New degradation mechanism of black tea pigment theaflavin involving condensation with epigallocatechin-3-O-gallate

    Tanaka, Takashi / Yasumatsu, Miho / Hirotani, Mayu / Matsuo, Yosuke / Li, Na / Zhu, Hong-Tao / Saito, Yoshinori / Ishimaru, Kanji / Zhang, Ying-Jun

    Food chemistry. 2022 Feb. 15, v. 370

    2022  

    Abstract: ... with epigallocatechin-3-O-gallate (EGCg), which is the most abundant polyphenol in tea leaves. In citrate–phosphate ...

    Abstract Theanaphthoquinone (TNQ) is the initial and main oxidation product of theaflavin, a representative black tea pigment. Nevertheless, TNQ is virtually undetected in the high-performance liquid chromatography analysis of black tea leaves using photodiode array detection. To elucidate the degradation mechanism of theaflavin in the black tea production process, this study investigated the reaction of TNQ with epigallocatechin-3-O-gallate (EGCg), which is the most abundant polyphenol in tea leaves. In citrate–phosphate buffer solution at pH 6 and room temperature, TNQ reacted nonenzymatically with EGCg to afford three products, whose structures were determined on the basis of spectroscopic data. The results indicated that the double bond of the ortho-naphthoquinone moiety in TNQ reacted with the autoxidation product of EGCg. This study demonstrates novel reactions occurring in the process of theaflavin degradation, which might be involved in the formation of thearubigins, the major black tea pigments composing oligomeric catechin oxidation products.
    Keywords ambient temperature ; autoxidation ; black tea ; catechin ; epigallocatechin gallate ; food chemistry ; high performance liquid chromatography ; moieties ; pH ; spectral analysis ; theaflavins
    Language English
    Dates of publication 2022-0215
    Publishing place Elsevier Ltd
    Document type Article
    ZDB-ID 243123-3
    ISSN 1873-7072 ; 0308-8146
    ISSN (online) 1873-7072
    ISSN 0308-8146
    DOI 10.1016/j.foodchem.2021.131326
    Database NAL-Catalogue (AGRICOLA)

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  9. Article: Three New Oxidation Products Produced from Epigallocatechin-3- O-gallate and Epicatechin-3-O-gallate.

    Li, Yan / Matsuo, Yosuke / Saito, Yoshinori / Tanaka, Takashi

    Natural product communications

    2016  Volume 11, Issue 2, Page(s) 189–192

    Abstract: ... of a mixture of epigallocatechin-3-O-gallate (1) and epicatechin-3-O-gallate (2) was examined, and three new ...

    Abstract During chemical studies on uncharacterized black tea polyphenols, the enzymatic oxidation of a mixture of epigallocatechin-3-O-gallate (1) and epicatechin-3-O-gallate (2) was examined, and three new dimeric products together with six known catechin dimers were isolated. Two of the new compounds have tricyclo[5.2.2.0²,⁶]undecane and tricyclo[5.2.1.0²,⁶]decane carboxyl structures generated by oxidative coupling between two pyrogallol-B-rings of 1. Another new product was a dimer connected by a C-C bond between the B-ring of 1 and a galloyl group of 2.
    MeSH term(s) Camellia sinensis/chemistry ; Catechin/analogs & derivatives ; Catechin/chemistry ; Molecular Structure ; Oxidation-Reduction
    Chemical Substances Catechin (8R1V1STN48) ; epicatechin gallate (92587OVD8Z) ; epigallocatechin gallate (BQM438CTEL)
    Language English
    Publishing date 2016-02
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ISSN 1934-578X
    ISSN 1934-578X
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Fine-tuned cholesterol solubilizer, mono-6-O-α-D-maltosyl-γ-cyclodextrin, ameliorates experimental Niemann-Pick disease type C without hearing loss.

    Yamada, Yusei / Miwa, Toru / Nakashima, Masaki / Shirakawa, Aina / Ishii, Akira / Namba, Nanami / Kondo, Yuki / Takeo, Toru / Nakagata, Naomi / Motoyama, Keiichi / Higashi, Taishi / Arima, Hidetoshi / Kurauchi, Yuki / Seki, Takahiro / Katsuki, Hiroshi / Okada, Yasuyo / Ichikawa, Atsushi / Higaki, Katsumi / Hayashi, Ken /
    Minami, Kentaro / Yoshikawa, Naoki / Ikeda, Ryuji / Ishikawa, Yoshihide / Kajii, Tomohito / Tachii, Kyoko / Takeda, Hiroki / Orita, Yorihisa / Matsuo, Muneaki / Irie, Tetsumi / Ishitsuka, Yoichi

    Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie

    2022  Volume 155, Page(s) 113698

    Abstract: ... but its physicochemical properties and ototoxicity remain a concern. Here, we evaluated the potential of mono-6-O-α-maltosyl-γ-CD (G2 ...

    Abstract Niemann-Pick disease type C (NPC) is a fatal disorder with abnormal intracellular cholesterol trafficking resulting in neurodegeneration and hepatosplenomegaly. A cyclic heptasaccharide with different degrees of substitution of 2-hydroxypropyl groups, 2-hydroxypropyl-β-cyclodextrin (HP-β-CD), acts as a strong cholesterol solubilizer and is under investigation for treating this disease in clinical trials, but its physicochemical properties and ototoxicity remain a concern. Here, we evaluated the potential of mono-6-O-α-maltosyl-γ-CD (G2-γ-CD), a single-maltose-branched cyclic octasaccharide with a larger cavity than HP-β-CD, for treating NPC. We identified that G2-γ-CD ameliorated NPC manifestations in model mice and showed lower ototoxicity in mice than HP-β-CD. To investigate the molecular mechanisms of action behind the differential ototoxicity of these CDs, we performed cholesterol solubility analysis, proton nuclear magnetic resonance spectroscopy, and molecular modeling, and estimated that the cholesterol inclusion mode of G2-γ-CD maintained solely the 1:1 inclusion complex, whereas that of HP-β-CD shifted to the highly-soluble 2:1 complex at higher concentrations. We predicted the associations of these differential complexations of CDs with cholesterol with the profile of disease attenuation and of the auditory cell toxicity using specific cell models. We proposed that G2-γ-CD can serve as a fine-tuned cholesterol solubilizer for treating NPC, being highly biocompatible and physicochemically suitable for clinical application.
    MeSH term(s) Mice ; Animals ; Niemann-Pick Disease, Type C/drug therapy ; 2-Hydroxypropyl-beta-cyclodextrin/pharmacology ; 2-Hydroxypropyl-beta-cyclodextrin/therapeutic use ; 2-Hydroxypropyl-beta-cyclodextrin/chemistry ; gamma-Cyclodextrins ; Maltose/therapeutic use ; Ototoxicity ; Protons ; Cholesterol/therapeutic use ; Excipients/therapeutic use ; Hearing Loss/drug therapy
    Chemical Substances 2-Hydroxypropyl-beta-cyclodextrin (1I96OHX6EK) ; gamma-Cyclodextrins ; Maltose (69-79-4) ; Protons ; Cholesterol (97C5T2UQ7J) ; Excipients
    Language English
    Publishing date 2022-09-16
    Publishing country France
    Document type Journal Article
    ZDB-ID 392415-4
    ISSN 1950-6007 ; 0753-3322 ; 0300-0893
    ISSN (online) 1950-6007
    ISSN 0753-3322 ; 0300-0893
    DOI 10.1016/j.biopha.2022.113698
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