18 results on '"Yuki Kitao"'
Search Results
2. Identification of Potent and Selective Inhibitors of Fat Mass Obesity-Associated Protein Using a Fragment-Merging Approach
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Yuri Takada, Yuki Kitao, Yoshie Fujiwara, Chika Yamamoto, Mitsuhiro Terao, Dan Ohtan Wang, Elghareeb E. Elboray, Yasunobu Yamashita, Yukihiro Itoh, Paolo Mellini, Rohini Roy, Yukari Takahashi, Makoto Oba, Masayuki Kotoku, Takao Yamaguchi, Satoshi Obika, Ritesh Singh, Muthuraj Prakash, and Takayoshi Suzuki
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Adenosine ,endocrine system diseases ,Alpha-Ketoglutarate-Dependent Dioxygenase FTO ,Down-Regulation ,Substrate Specificity ,chemistry.chemical_compound ,Downregulation and upregulation ,Cell Line, Tumor ,Drug Discovery ,medicine ,Humans ,Acute monocytic leukemia ,Epigenetics ,Enzyme Inhibitors ,Gene ,Messenger RNA ,biology ,Chemistry ,nutritional and metabolic diseases ,RNA ,pathological conditions, signs and symptoms ,medicine.disease ,Molecular biology ,Up-Regulation ,Drug Design ,biology.protein ,Molecular Medicine ,Demethylase ,DNA - Abstract
Fat mass obesity-associated protein (FTO) is a DNA/RNA demethylase involved in the epigenetic regulation of various genes and is considered a therapeutic target for obesity, cancer, and neurological disorders. Here, we aimed to design novel FTO-selective inhibitors by merging fragments of previously reported FTO inhibitors. Among the synthesized analogues, compound 11b, which merges key fragments of Hz (3) and MA (4), inhibited FTO selectively over alkylation repair homologue 5 (ALKBH5), another DNA/RNA demethylase. Treatment of acute monocytic leukemia NOMO-1 cells with a prodrug of 11b decreased the viability of acute monocytic leukemia cells, increased the level of the FTO substrate N6-methyladenosine in mRNA, and induced upregulation of MYC and downregulation of RARA, which are FTO target genes. Thus, Hz (3)/MA (4) hybrid analogues represent an entry into a new class of FTO-selective inhibitors.
- Published
- 2021
3. Effect of matcha consumption on gut microbiota in healthy Japanese individuals: study protocol for a double-blind crossover interventional study
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Takashi Yoshimura, Tomoki Miyoshi, Yuki Kitao, Masahide Hamaguchi, Naoko Nakanishi, Kazutsugu Kinoshita, Yoshitaka Hashimoto, Chihiro Munekawa, Tomonori Kimura, Hanako Nakajima, Michiaki Fukui, Takuro Okamura, and Maya Takegami
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Consumption (economics) ,Protocol (science) ,medicine.medical_specialty ,Nutrition and Dietetics ,biology ,business.industry ,Clinical Biochemistry ,Crossover ,Medicine (miscellaneous) ,Gut flora ,biology.organism_classification ,Double blind ,Internal medicine ,medicine ,business - Abstract
Background: This study compares and clarifies the changes in intestinal flora resulting from the continuous consumption of two types of matcha.Methods: Healthy adults will consume two types of matcha tea for four weeks, and differences in the intestinal microflora before and after drinking will be compared. Gut microbiota will be identified using next-generation sequencing (NGS). Phylogenetic classification of the enterobacteria will be performed based on sequence similarities. The relative proportions of the classified enterobacteria to the total nucleotide sequences will be compared between the samples obtained from the two groups consuming different matcha.Discussion: The continuous consumption of matcha may improve dysbiosis and prevent atherosclerosis. The effects may vary according to the type of matcha used.Trial registration:The study was registered with university hospital medical information network (UMIN) (UMIN000040303), and all participants gave their written informed consent. Registered 1 November 2020, https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000045982.
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- 2021
4. Identification of Diketopiperazine-Containing 2-Anilinobenzamides as Potent Sirtuin 2 (SIRT2)-Selective Inhibitors Targeting the 'Selectivity Pocket', Substrate-Binding Site, and NAD+-Binding Site
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Yuki Kitao, Yuri Miura, Miki Suzuki, Masayuki Kotoku, Tetsuya Iida, Yuka Miyake, Hiroki Tsumoto, Yukari Takahashi, Elghareeb E. Elboray, Paolo Mellini, Takayoshi Suzuki, Ying Li, Yukihiro Itoh, Toshifumi Tojo, and Takashi Kurohara
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Protein Conformation ,Stereochemistry ,Diketopiperazines ,SIRT2 ,01 natural sciences ,Substrate Specificity ,Structure-Activity Relationship ,03 medical and health sciences ,Sirtuin 2 ,Sirtuin 1 ,Drug Discovery ,Humans ,Enzyme Inhibitors ,Binding site ,Thioamide ,030304 developmental biology ,chemistry.chemical_classification ,0303 health sciences ,Binding Sites ,biology ,NAD ,0104 chemical sciences ,Molecular Docking Simulation ,NAD binding ,010404 medicinal & biomolecular chemistry ,chemistry ,Benzamides ,Sirtuin ,MCF-7 Cells ,biology.protein ,Molecular Medicine ,NAD+ kinase ,Selectivity ,Conjugate - Abstract
The NAD+-dependent deacetylase SIRT2 represents an attractive target for drug development. Here, we designed and synthesized drug-like SIRT2-selective inhibitors based on an analysis of the putative binding modes of recently reported SIRT2-selective inhibitors and evaluated their SIRT2-inhibitory activity. This led us to develop a more drug-like diketopiperazine structure as a "hydrogen bond (H-bond) hunter" to target the substrate-binding site of SIRT2. Thioamide 53, a conjugate of diketopiperazine and 2-anilinobenzamide which is expected to occupy the "selectivity pocket" of SIRT2, exhibited potent SIRT2-selective inhibition. Inhibition of SIRT2 by 53 was mediated by the formation of a 53-ADP-ribose conjugate, suggesting that 53 is a mechanism-based inhibitor targeting the "selectivity pocket", substrate-binding site, and NAD+-binding site. Furthermore, 53 showed potent antiproliferative activity toward breast cancer cells and promoted neurite outgrowth of Neuro-2a cells. These findings should pave the way for the discovery of novel therapeutic agents for cancer and neurological disorders.
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- 2019
5. Discovery of Selective Transforming Growth Factor β Type II Receptor Inhibitors as Antifibrosis Agents
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Yoshifumi Ueyama, Yutaka Ukaji, Keisuke Nozawa, Katsuya Maeda, Shohei Miwa, Tomohiro Ishikawa, Yuki Kitao, Tsuyoshi Adachi, Naoki Ogawa, Makoto Shiozaki, Yokota Masahiro, Yosuke Ogoshi, Seki Noriyoshi, Jun Nishihata, and Akihiro Nomura
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010405 organic chemistry ,Chemistry ,Organic Chemistry ,Human skin ,medicine.disease ,01 natural sciences ,Biochemistry ,Phenotype ,0104 chemical sciences ,010404 medicinal & biomolecular chemistry ,Collagen, type I, alpha 1 ,Fibrosis ,Drug Discovery ,Cancer research ,Functional selectivity ,medicine ,Receptor ,Tissue homeostasis ,Transforming growth factor - Abstract
[Image: see text] Historically, modulation of transforming growth factor β (TGF-β) signaling has been deemed a rational strategy to treat many disorders, though few successful examples have been reported to date. This difficulty could be partially attributed to the challenges of achieving good specificity over many closely related enzymes that are implicated in distinct phenotypes in organ development and in tissue homeostasis. Recently, fresolimumab and disitertide, two peptidic TGF-β blockers, demonstrated significant therapeutic effects toward human skin fibrosis. Therefore, the selective blockage of TGF-β signaling assures a viable treatment option for fibrotic skin disorders such as systemic sclerosis (SSc). In this report, we disclose selective TGF-β type II receptor (TGF-βRII) inhibitors that exhibited high functional selectivity in cell-based assays. The representative compound 29 attenuated collagen type I alpha 1 chain (COL1A1) expression in a mouse fibrosis model, which suggests that selective inhibition of TGF-βRII-dependent signaling could be a new treatment for fibrotic disorders.
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- 2020
6. Identification of Potent and Selective Inhibitors of Fat Mass Obesity-Associated Protein Using a Fragment-Merging Approach.
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Muthuraj Prakash, Yukihiro Itoh, Yoshie Fujiwara, Yukari Takahashi, Yuri Takada, Mellini, Paolo, Elboray, Elghareeb E., Mitsuhiro Terao, Yasunobu Yamashita, Chika Yamamoto, Takao Yamaguchi, Masayuki Kotoku, Yuki Kitao, Singh, Ritesh, Roy, Rohini, Satoshi Obika, Makoto Oba, Dan Ohtan Wang, and Takayoshi Suzuki
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- 2021
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7. Molecular mechanisms of action of different concentrations of ethanol in water on ordered structures of intercellular lipids and soft keratin in the stratum corneum
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Ichiro Hatta, Daisuke Horita, Hiroaki Todo, Masato Yoshimoto, Yuki Kitao, and Kenji Sugibayashi
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endocrine system ,Hairless mouse ,Protein Conformation ,Skin Absorption ,Biophysics ,Stratum corneum ,Fibril ,Biochemistry ,Permeability ,chemistry.chemical_compound ,Membrane Lipids ,X-Ray Diffraction ,Keratin ,mental disorders ,Scattering, Small Angle ,medicine ,Animals ,Lamellar structure ,Corneocyte ,reproductive and urinary physiology ,Skin ,chemistry.chemical_classification ,Mice, Hairless ,Ethanol ,Aqueous solution ,integumentary system ,Dose-Response Relationship, Drug ,Water ,Cell Biology ,Permeation ,Intercellular lipids ,medicine.anatomical_structure ,chemistry ,Keratins ,Synchrotrons - Abstract
Ethanol (EtOH) is one of the bases in topically applied medicines that promote the skin permeation of drugs. Although the effects of EtOH have been attributed to structural modifications in the stratum corneum, the underlying mechanisms, especially the influence of different concentrations of EtOH, have not been examined extensively. Structural modifications in the stratum corneum of hairless mouse due to the application of EtOH/water mixture were herein investigated at the molecular level using synchrotron X-ray diffraction. The results revealed that all EtOH concentrations examined greatly modified the short lamellar structures containing the aqueous layer in intercellular lipids and the structure of keratin fibrils in corneocytes, which can take up hydrophilic compounds. However, the long lamellar and the hydrocarbon-chain packing structures were unaffected by EtOH. Changes to the short lamellar structures were not proportional to the concentration of EtOH. However, the keratin fibril structures changed gradually with increasing EtOH concentration. The X-ray diffraction experiments enabled the effects of different EtOH concentrations on the morphology of the stratum corneum to be assessed by using a number of experimental samples to avoid variations due to individual differences. The results indicated that alterations to the short lamellar structures appeared to be related to the skin permeability of drugs with the application of EtOH/water mixture, and monotonous structural changes in the keratin fibrils with an increase in EtOH concentration may contribute to this permeation as supplement. These results will be useful for the development of new drug formulations containing EtOH.
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- 2015
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8. High-Throughput Screening of Potential Skin Penetration-Enhancers Using Stratum Corneum Lipid Liposomes: Preliminary Evaluation for Different Concentrations of Ethanol
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Hiroaki Todo, Yuki Kitao, Pajaree Sakdiset, and Kenji Sugibayashi
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0301 basic medicine ,Liposome ,Ethanol ,Chromatography ,Article Subject ,integumentary system ,High-throughput screening ,lcsh:RS1-441 ,Permeation ,Fluorescence ,Hairless ,lcsh:Pharmacy and materia medica ,03 medical and health sciences ,chemistry.chemical_compound ,030104 developmental biology ,0302 clinical medicine ,medicine.anatomical_structure ,chemistry ,030220 oncology & carcinogenesis ,Stratum corneum ,medicine ,Enhancer ,Research Article - Abstract
In this study, we developed a technique for high-throughput screening (HTS) of skin penetration-enhancers using stratum corneum lipid liposomes (SCLLs). A fluorescent marker, sodium fluorescein (FL), entrapped in SCLLs was prepared to provide a preliminary evaluation of the effect of different concentrations of ethanol on the disruption effect of SCLLs, which is an alternative for skin penetration-enhancing effects. In addition, SCLLs containing a fluorescent probe (DPH, TMA-DPH, or ANS) were also prepared and utilized to investigate SCLL fluidity. The results using SCLL-based techniques were compared with conventional skin permeation and skin impedance test using hairless rat skin. The obtained correlations were validated between FL leakage, SCLL fluidity with various probes, or skin impedance and increases in the skin permeation enhancement ratio (ER) of caffeine as a model penetrant. As a result, FL leakage and SCLL fluidity using ANS were considered to be good indices for the skin penetration-enhancing effect, suggesting that the action of ethanol on the SC lipid and penetration-enhancing is mainly on the polar head group of intercellular lipids. In addition, this screening method using SCLL could be utilized as an alternative HTS technique for conventional animal tests. Simultaneously, the method was found to be time-saving and sensitive compared with a direct assay using human and animal skins., A peer-reviewed, Open Access journal
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- 2017
9. Discovery of INT131: A selective PPARγ modulator that enhances insulin sensitivity
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Marc Learned, Steven M. Rubenstein, Juan C. Jaen, Hisashi Shinkai, Jun Nishiu, Holger Beckmann, Alykhan Motani, Jin-Long Chen, Yuki Kitao, Lawrence R. McGee, Martin Thoolen, Patrick C. Kearney, Yang Li, Atsushi Hagiwara, Jinsong Liu, Guosen Ye, Michelle Lindstrom, Timothy D. Cushing, Joshua Taygerly, John A. Flygare, Nigel Walker, Jennifer Weiszmann, Tetsuya Iida, Walter P. Frankmoelle, Zhulun Wang, Shichang Miao, Hisateru Aramaki, Pieter B. M. W. M. Timmermans, Noboru Furukawa, Jonathan B. Houze, Donna H.T. Biermann, and Motonao Nakamura
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Male ,medicine.drug_class ,Clinical Biochemistry ,Administration, Oral ,Pharmaceutical Science ,Pharmacology ,Crystallography, X-Ray ,Biochemistry ,Partial agonist ,Diabetes Mellitus, Experimental ,Rats, Sprague-Dawley ,Mice ,Structure-Activity Relationship ,Cytochrome P-450 Enzyme System ,Drug Discovery ,medicine ,Animals ,Cytochrome P-450 CYP3A ,Cytochrome P-450 Enzyme Inhibitors ,Glucose homeostasis ,Thiazolidinedione ,Molecular Biology ,Sulfonamides ,Binding Sites ,Chemistry ,Organic Chemistry ,Insulin sensitivity ,Protein Structure, Tertiary ,Rats ,Rats, Zucker ,PPAR gamma ,Nuclear receptor ,Quinolines ,Molecular Medicine ,Insulin Resistance ,Half-Life - Abstract
PPARγ is a member of the nuclear hormone receptor family and plays a key role in the regulation of glucose homeostasis. This Letter describes the discovery of a novel chemical class of diarylsulfonamide partial agonists that act as selective PPARγ modulators (SPPARγMs) and display a unique pharmacological profile compared to the thiazolidinedione (TZD) class of PPARγ full agonists. Herein we report the initial discovery of partial agonist 4 and the structure–activity relationship studies that led to the selection of clinical compound INT131 (3), a potent PPARγ partial agonist that displays robust glucose-lowering activity in rodent models of diabetes while exhibiting a reduced side-effects profile compared to marketed TZDs.
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- 2013
10. Characterization of Protein-like Fluorophores Released from Lake Phytoplankton on the Basis of Fractionation and Electrophoresis
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Yuki Kitao, Toshiro Matsunaga, Yasuro Fuse, Naoko Hatori, Hajime Karatani, Etsu Yamada, Takaaki Hirota, and Shinichi Aoki
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Gel electrophoresis ,Microcystis ,Chromatography ,biology ,Molecular mass ,Chemistry ,Size-exclusion chromatography ,Eukaryota ,Fractionation ,biology.organism_classification ,Fluorescence spectroscopy ,Analytical Chemistry ,Molecular Weight ,Gel permeation chromatography ,Electrophoresis ,Phytoplankton ,Electrophoresis, Polyacrylamide Gel ,Microcystis aeruginosa ,Fluorescent Dyes - Abstract
Three kinds of lake plankton were cultivated, and the properties of protein-like fluorophores released from the plankton were characterized using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The results were compared with those by gel chromatography with a fluorescence detector and three-dimensional excitation-emission matrix (3-DEEM). The concentrated protein-like fluorophores of algal dissolved organic matter (DOM) were successfully separated from the fulvic-like fluorophores, and analyzed using SDS-PAGE. SDS-PAGE analysis revealed that the protein-like fluorescence DOM released from Microcystis aeruginosa consisted of proteins with molecular weights of 17, 37, 50, 75, 150 kDa, and greater than 250 kDa. The results of SDS-PAGE were consistent with those of gel chromatography. Those substances with molecular weights greater than 250 kDa may be a polysaccharide-peptide complex, called peptidoglycan, which is a component of bacterial cell walls. The molecular weights of protein-like fluorescence DOM from Staurastrum dorsidentiferum were determined to be 37 and 50 kDa. For Cryptomonas ovata, its DOM was found to be composed of substances with molecular weights of between 10 and 150 kDa. The results by high-performance size exclusion chromatography with chemiluminescent nitrogen detection (HPSEC/CLND) analysis suggest that the protein-like fluorophores from the plankton might be composed of substances containing organic nitrogen.
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- 2012
11. Molecular Assembly of Wheat Gliadins into Nanostructures: A Small-Angle X-ray Scattering Study of Gliadins in Distilled Water over a Wide Concentration Range
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Yuki Higashino, Yojiro Oba, Masaaki Sugiyama, Reiko Urade, Satoshi Funaki, Nobuhiro Sato, Fumio Arisaka, Yuki Kitao, Rintaro Inoue, and Aoi Matsumiya
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Nanostructure ,Static Electricity ,Wheat flour ,digestive system ,Gliadin ,chemistry.chemical_compound ,Glutenin ,Scattering, Small Angle ,Triticum ,chemistry.chemical_classification ,biology ,Chemistry ,Small-angle X-ray scattering ,fungi ,nutritional and metabolic diseases ,food and beverages ,General Chemistry ,Gluten ,digestive system diseases ,Crystallography ,Monomer ,Chemical engineering ,Distilled water ,biology.protein ,General Agricultural and Biological Sciences - Abstract
Gliadin, one of the major proteins together with glutenin composing gluten, affects the physical properties of wheat flour dough. In this study, nanoscale structures of hydrated gliadins extracted into distilled water were investigated primarily by small-angle X-ray scattering (SAXS) over a wide range of concentrations. Gliadins are soluble in distilled water below 10 wt %. Guinier analyses of SAXS profiles indicate that gliadins are present as monomers together with small amounts of dimers and oligomers in a very dilute solution. The SAXS profiles also indicate that interparticle interference appears above 0.5 wt % because of electrostatic repulsion among gliadin assemblies. Above 15 wt %, gliadins form gel-like hydrated solids. At greater concentrations, a steep upturn appears in the low-q region owing to the formation of large aggregates, and a broad shoulder appears in the middle-q region showing density fluctuation inside. This study demonstrates that SAXS can effectively disclose the nanostructure of hydrated gliadin assemblies.
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- 2015
12. Expression and characterization of protein disulfide isomerase family proteins in bread wheat
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Reiko Urade, Yuki Higashino, Taro Masuda, Shizuka Kimura, and Yuki Kitao
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Protein Disulfide-Isomerase Family ,Protein Disulfide-Isomerases ,Plant Science ,Bread wheat ,Genes, Plant ,Endosperm ,Gene Expression Regulation, Plant ,Aleurone ,Storage protein ,Ribonuclease ,Cloning, Molecular ,Protein disulfide-isomerase ,Triticum ,Aleurone cell ,Endoplasmic reticulum Bread wheat ,Plant Proteins ,chemistry.chemical_classification ,biology ,Endoplasmic reticulum ,food and beverages ,Starch ,Bread ,Starchy endosperm ,Protein disulfide isomerase ,Recombinant Proteins ,Transport protein ,Protein Transport ,Biochemistry ,chemistry ,Multigene Family ,biology.protein ,Oxidative refolding ,Oxidation-Reduction ,Research Article ,Subcellular Fractions - Abstract
Background The major wheat seed proteins are storage proteins that are synthesized in the rough endoplasmic reticulum (ER) of starchy endosperm cells. Many of these proteins have intra- and intermolecular disulfide bonds. In eukaryotes, the formation of most intramolecular disulfide bonds in the ER is thought to be catalyzed by protein disulfide isomerase (PDI) family proteins. The cDNAs that encode eight groups of bread wheat (Triticum aestivum L.) PDI family proteins have been cloned, and their expression levels in developing wheat grains have been determined. The purpose of the present study was to characterize the enzymatic properties of the wheat PDI family proteins and clarify their expression patterns in wheat caryopses. Results PDI family cDNAs, which are categorized into group I (TaPDIL1Aα, TaPDIL1Aβ, TaPDIL1Aγ, TaPDIL1Aδ, and TaPDIL1B), group II (TaPDIL2), group III (TaPDIL3A), group IV (TaPDIL4D), and group V (TaPDIL5A), were cloned. The expression levels of recombinant TaPDIL1Aα, TaPDIL1B, TaPDIL2, TaPDIL3A, TaPDIL4D, and TaPDIL5A in Escherichia coli were established from the cloned cDNAs. All recombinant proteins were expressed in soluble forms and purified. Aside from TaPDIL3A, the recombinant proteins exhibited oxidative refolding activity on reduced and denatured ribonuclease A. Five groups of PDI family proteins were distributed throughout wheat caryopses, and expression levels of these proteins were higher during grain filling than in the late stage of maturing. Localization of these proteins in the ER was confirmed by fluorescent immunostaining of the immature caryopses. In mature grains, the five groups of PDI family proteins remained in the aleurone cells and the protein matrix of the starchy endosperm. Conclusions High expression of PDI family proteins during grain filling in the starchy endosperm suggest that these proteins play an important role in forming intramolecular disulfide bonds in seed storage proteins. In addition, these PDI family proteins that remain in the aleurone layers of mature grains likely assist in folding newly synthesized hydrolytic enzymes during germination. Electronic supplementary material The online version of this article (doi:10.1186/s12870-015-0460-2) contains supplementary material, which is available to authorized users.
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- 2015
13. Inhibitory effect of JTP-59557, a new triazole derivative, on intestinal phosphate transport in vitro and in vivo
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Ken-ichi Miyamoto, Hiroko Segawa, Masanori Shindo, Tomohisa Seo, Tamotsu Negoro, Akira Matsuo, and Yuki Kitao
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Male ,Brush border ,Gene Expression ,CHO Cells ,Sodium-Phosphate Cotransporter Proteins, Type IIb ,Phosphates ,Rats, Sprague-Dawley ,Cricetulus ,Non-competitive inhibition ,In vivo ,Cricetinae ,Pi ,Animals ,Humans ,Intestinal Mucosa ,Ligation ,Pharmacology ,Dose-Response Relationship, Drug ,Microvilli ,Symporters ,Chemistry ,Vesicle ,Chinese hamster ovary cell ,Biological Transport ,Sodium-Phosphate Cotransporter Proteins ,Triazoles ,Molecular biology ,In vitro ,Rats ,Intestines ,Kinetics ,Intestinal Absorption ,Biochemistry ,Phosphorus, Dietary ,Rabbits ,Cotransporter ,Foscarnet - Abstract
JTP-59557 [(-)-4-(2-tert-Butyl-4,5-dichlorophenyl)-5-(5-trifluoromethylpyridin-2-ylsulfanyl)-4H-[1,2,4]triazol-3-ol] showed an inhibitory effect on Na(+)-dependent inorganic phosphate (Pi) transport in intestinal brush border membrane vesicles with an IC(50) value of 0.40 microM in rabbit and with an IC(50) of 0.19 microM in rat, without affecting Na(+)-independent Pi and Na(+)-dependent d-glucose transport activities. In Chinese hamster ovary (CHO) cells expressing human type IIb Na/Pi cotransporter (type IIb), JTP-59557 decreased human type IIb-mediated Pi uptake with an IC(50) of 0.12 microM. In rabbit intestinal brush border membrane vesicles, JTP-59557 behaved as a noncompetitive inhibitor with respect to Pi. In an in vivo study, single administration of JTP-59557 significantly decreased the intestinal Pi absorption rate, when either Pi solution or laboratory chow was given to rats. In this report, we show that JTP-59557 is a potent, selective, stereospecific, noncompetitive inhibitor of intestinal Na/Pi cotransporters including type IIb, and it may represent a new class of intestinal Pi absorption inhibitor.
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- 2005
14. Development of Repairing Method of CFRP Laminate Using TASC Technique
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Takayuki Kusaka, Yuki Kitao, and Hajime Honda
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Engineering ,business.industry ,Structural engineering ,business - Published
- 2017
15. ChemInform Abstract: 4-Aminoquinolines: Novel Nociceptin Antagonists with Analgesic Activity
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Itsuo Uchida, Hideki Yamada, Tetsuya Iida, Ito Takao, Hisashi Shinkai, and Yuki Kitao
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medicine.drug_class ,Analgesic ,Antagonist ,General Medicine ,(+)-Naloxone ,Pharmacology ,Nociceptin receptor ,chemistry.chemical_compound ,Allodynia ,chemistry ,medicine ,medicine.symptom ,Hot plate test ,Benzamide ,Opioid antagonist - Abstract
Small-molecule nociceptin antagonists were synthesized to examine their therapeutic potential. After a 4-aminoquinoline derivative was found to bind with the human ORL1 receptor, a series of 4-aminoquinolines and related compounds were synthesized and their binding was evaluated. Elucidation of structure−activity relationships eventually led to the optimum compounds. One of these compounds, N-(4-amino-2-methylquinolin-6-yl)-2-(4-ethylphenoxymethyl)benzamide hydrochloride (11) not only antagonized nociceptin-induced allodynia in mice but also showed analgesic effect in a hot plate test using mice and in a formalin test using rats. Its analgesic effect was not antagonized by the opioid antagonist naloxone. These results indicate that this nociceptin antagonist has the potential to become a novel type of analgesic that differs from μ-opioid agonists.
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- 2001
16. 4-Aminoquinolines: novel nociceptin antagonists with analgesic activity
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Yuki Kitao, Itsuo Uchida, Ito Takao, Hisashi Shinkai, Tetsuya Iida, and Hideki Yamada
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Male ,medicine.drug_class ,Narcotic Antagonists ,Analgesic ,JTC-801 ,Drug Evaluation, Preclinical ,Receptors, Opioid, mu ,(+)-Naloxone ,Pharmacology ,Cell Line ,chemistry.chemical_compound ,Mice ,Radioligand Assay ,Structure-Activity Relationship ,Receptors, Opioid, delta ,Drug Discovery ,medicine ,Animals ,Humans ,Hot plate test ,Benzamide ,Pain Measurement ,Analgesics ,Mice, Inbred ICR ,Chemistry ,Naloxone ,Receptors, Opioid, kappa ,Antagonist ,Adenosine Monophosphate ,Nociceptin receptor ,Opioid Peptides ,Benzamides ,Aminoquinolines ,Molecular Medicine ,Opioid antagonist ,medicine.drug - Abstract
Small-molecule nociceptin antagonists were synthesized to examine their therapeutic potential. After a 4-aminoquinoline derivative was found to bind with the human ORL(1) receptor, a series of 4-aminoquinolines and related compounds were synthesized and their binding was evaluated. Elucidation of structure-activity relationships eventually led to the optimum compounds. One of these compounds, N-(4-amino-2-methylquinolin-6-yl)-2-(4-ethylphenoxymethyl)benzamide hydrochloride (11) not only antagonized nociceptin-induced allodynia in mice but also showed analgesic effect in a hot plate test using mice and in a formalin test using rats. Its analgesic effect was not antagonized by the opioid antagonist naloxone. These results indicate that this nociceptin antagonist has the potential to become a novel type of analgesic that differs from mu-opioid agonists.
- Published
- 2000
17. Determination of absolute configuration and biological activity of new immunosuppressants, mycestericins D, E, F and G
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Yuki Kitao, Shigeo Sasaki, Kenichiro Inoue, Masatoshi Kiuchi, Masahiko Yoneta, Kenji Chiba, Tetsuro Fujita, Tohru Matsuzaki, Norimitsu Hamamichi, and Ryoji Hirose
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Pharmacology ,Circular dichroism ,Molecular Structure ,Chemistry ,Stereochemistry ,Circular Dichroism ,Absolute configuration ,Biological activity ,Mixed lymphocyte reaction ,Fatty Acids, Monounsaturated ,Mice ,Fatty acids.monounsaturated ,Drug Discovery ,Fatty Acids, Unsaturated ,Mycelia sterilia ,Molecule ,Animals ,Lymphocytes ,Immunosuppressive Agents - Abstract
Mycestericins D, E, F and G were isolated from the culture broth of Mycelia sterilia ATCC 20349 as potent immunosuppressants. Mycestericins F and G were identical with dihydromycestericins D and E, respectively. Their absolute configurations were determined by use of the modified MOSHER'S method and by comparison of the CD spectra of their benzoate derivatives with those of synthetic analogs. Mycestericins D, E, F and G suppressed the proliferation of lymphocytes in the mouse allogeneic mixed lymphocyte reaction.
- Published
- 1996
18. Molecular Assembly of Wheat Gliadins into Nanostructures: A Small-Angle X-ray Scattering Study of Gliadins in Distilled Water over a Wide Concentration Range.
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Nobuhiro Sato, Aoi Matsumiya, Yuki Higashino, Satoshi Funaki, Yuki Kitao, Yojiro Oba, Rintaro Inoue, Fumio Arisaka, Masaaki Sugiyama, and Reiko Urade
- Published
- 2015
- Full Text
- View/download PDF
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