17 results on '"Ryo Endo"'
Search Results
2. Pretreatment with cilnidipine attenuates hypoxia/reoxygenation injury in HL-1 cardiomyocytes through enhanced NO production and action potential shortening
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Naoe Nakasone, Junichiro Miake, Yasuaki Shirayoshi, Yoshimi Inagaki, Motokazu Tsuneto, Yasutaka Kurata, Futoshi Okada, Ryo Endo, Hiroyuki Minato, Haruaki Ninomiya, Akihiro Okamura, Akihiro Otsuki, Takuya Tomomori, Ichiro Hisatome, Toshihiro Hamada, and Tomomi Notsu
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Dihydropyridines ,Nitric Oxide Synthase Type III ,Physiology ,Cell Survival ,Action Potentials ,Apoptosis ,030204 cardiovascular system & hematology ,Pharmacology ,Endothelial NOS ,Nitric Oxide ,Nitric oxide ,Cell Line ,03 medical and health sciences ,chemistry.chemical_compound ,Mice ,0302 clinical medicine ,Enos ,Internal Medicine ,medicine ,Animals ,Channel blocker ,Myocytes, Cardiac ,030212 general & internal medicine ,Phosphorylation ,RNA, Small Interfering ,Hypoxia ,biology ,Cilnidipine ,biology.organism_classification ,medicine.disease ,Calcium Channel Blockers ,Rats ,Nitric oxide synthase ,chemistry ,Gene Knockdown Techniques ,biology.protein ,Cardiology and Cardiovascular Medicine ,Reperfusion injury ,medicine.drug - Abstract
Myocardial ischemia/reperfusion injury worsens in the absence of nitric oxide synthase (NOS). Cilnidipine, a Ca2+ channel blocker, has been reported to activate endothelial NOS (eNOS) and increases nitric oxide (NO) in vascular endothelial cells. We examined whether pretreatment with cilnidipine could attenuate cardiac cell deaths including apoptosis caused by hypoxia/reoxygenation (H/R) injury. HL-1 mouse atrial myocytes as well as H9c2 rat ventricular cells were exposed to H/R, and cell viability was evaluated by an autoanalyzer and flow cytometry; eNOS expression, NO production, and electrophysiological properties were also evaluated by western blotting, colorimetry, and patch clamping, respectively, in the absence and presence of cilnidipine. Cilnidipine enhanced phosphorylation of eNOS and NO production in a concentration-dependent manner, which was abolished by siRNAs against eNOS or an Hsp90 inhibitor, geldanamycin. Pretreatment with cilnidipine attenuated cell deaths including apoptosis during H/R; this effect was reproduced by an NO donor and a xanthine oxidase inhibitor. The NOS inhibitor L-NAME abolished the protective action of cilnidipine. Pretreatment with cilnidipine also attenuated H9c2 cell death during H/R. Additional cilnidipine treatment during H/R did not significantly enhance its protective action. There was no significant difference in the protective effect of cilnidipine under normal and high Ca2+ conditions. Action potential duration (APD) of HL-1 cells was shortened by cilnidipine, with this shortening augmented after H/R. L-NAME attenuated the APD shortening caused by cilnidipine. These findings indicate that cilnidipine enhances NO production, shortens APD in part by L-type Ca2+ channel block, and thereby prevents HL-1 cell deaths during H/R.
- Published
- 2019
3. Fabrication of porous chitin with continuous substructure by regeneration from gel with CaBr 2 ·2H 2 O/methanol
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Kazuya Yamamoto, Keisuke Ohta, Kohei Tanaka, Jun-ichi Kadokawa, and Ryo Endo
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Bromides ,Materials science ,Fabrication ,Morphology (linguistics) ,Scanning electron microscope ,Methanol ,Regeneration (biology) ,Chitin ,General Medicine ,Calcium Compounds ,Biochemistry ,chemistry.chemical_compound ,Chemical engineering ,chemistry ,Structural Biology ,Substructure ,Porosity ,Gels ,Molecular Biology - Abstract
In this study, we investigated the fabrication of porous chitins with continuous channel substructure by regeneration from gels with CaBr2·2H2O/methanol solution. After rapidly removing methanol from the gels, the products were immersed in methanol, followed by washing out CaBr2 with water and lyophilization to obtain regenerated chitins with inter-connected continuous pore morphology. Scanning electron microscopic results supported that the materials were consisted of continuous substructures of porous channels. The materials were further characterized by SEM-EDX and XRD measurements. The mechanical property and water absorbability were also evaluated. The plausible mechanism for the formation of the inter-connected pore morphology during the regeneration procedure was discussed.
- Published
- 2015
4. Preparation of Chitin Nanofiber-Reinforced Cellulose Films Through Stepwise Regenerations from Individually Prepared Ion Gels
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Daisuke Hatanaka, Jun-ichi Kadokawa, Ryo Endo, and Kazuya Yamamoto
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Environmental Engineering ,Materials science ,Polymers and Plastics ,Composite number ,Compatibilization ,Amorphous solid ,chemistry.chemical_compound ,Chitin ,chemistry ,Chemical engineering ,Bromide ,Nanofiber ,Ionic liquid ,Polymer chemistry ,Materials Chemistry ,Cellulose - Abstract
In this study, we investigated the preparation of chitin nanofiber (CNF)-reinforced cellulose films through stepwise regeneration procedures from the respective ion gels with ionic liquids. Self-assembled CNF dispersions were prepared by regeneration from the chitin ion gel with the ionic liquid, 1-allyl-3-methylimidazolium bromide, using methanol, followed by dilution with adjusted amounts of methanol. Cellulose ion gels with the ionic liquid, 1-butyl-3-methylimidazolium chloride, were then prepared, soaked in the CNF dispersions, and centrifuged to simultaneously occur regeneration of cellulose and compatibilization with the CNFs. Soxhlet extraction with methanol and subsequent drying of the resulting materials gave the CNF/cellulose composite films. The IR and SEM results of the films indicated the presence of CNFs not only on the surfaces of the films but also inside the films. Powder X-ray diffraction patterns showed the amorphous structure of the cellulose in the film. Tensile testing of the films suggested the reinforcing effect of the CNFs on the mechanical properties of the films.
- Published
- 2015
5. Acetylation of Xanthan Gum in Ionic Liquid
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Jun-ichi Kadokawa, Ryo Endo, Miwa Setoyama, and Kazuya Yamamoto
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Thermogravimetric analysis ,Environmental Engineering ,Polymers and Plastics ,Chemistry ,Chloride ,Solvent ,chemistry.chemical_compound ,Acetic anhydride ,Ionic liquid ,Materials Chemistry ,medicine ,Proton NMR ,Organic chemistry ,Thermal stability ,Xanthan gum ,medicine.drug ,Nuclear chemistry - Abstract
In this paper, we report acetylation of xanthan gum using acetic anhydride in an ionic liquid solvent, 1-butyl-3-methylimidazolium chloride (BMIMCl). Xanthan gum was dissolved with BMIMCl [2 % (w/w)] and the reaction was carried out in the presence of acetic anhydride (five equiv. for hydroxy groups in a repeating unit) with stirring the solution at elevated temperatures. The structures of xanthan gum acetates were confirmed by the 1H NMR and IR spectra. The degree of acetylation (DA) values determined by the 1H NMR analysis increased with the higher reaction temperatures. The thermal gravimetric analysis (TGA) indicated the enhancement of thermal stability by acetylation. Furthermore, the TGA as well as differential scanning calorimetric (DSC) analysis of the products suggested the presence of the highly and less acetylated segments in a xanthan gum chain. The DSC profile of the product with the high DA value also exhibited a small endothermic peak, which might potentially be ascribed to the melting temperature.
- Published
- 2014
6. Possibility of Formic and Acetic Acids as Active Substrates for Methanogenesis in the Groundwater in Horonobe, Hokkaido
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Teruki Iwatsuki, Yasushi Omi, Shuji Tamamura, Toshifumi Igarashi, Ryo Endo, Satoru Shimizu, and Yuki Amano
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Waste management ,Chemistry ,Methanogenesis ,Environmental chemistry ,Groundwater - Published
- 2012
7. FAD012, a ferulic acid derivative, protects against middle cerebral artery occlusion (MCAO)-induced ischemic stroke by preserving cerebral blood flow in rats
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Kosuke Hayashi, Naohiro Iwata, Yosuke Kato, Ryo Endo, Takashi Asano, Takeshi Sakamoto, Yasuhide Hibino, Mari Okazaki, and Hirokazu Matsuzaki
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medicine.medical_specialty ,business.industry ,Applied Mathematics ,General Mathematics ,Ferulic acid ,chemistry.chemical_compound ,chemistry ,Cerebral blood flow ,Internal medicine ,Ischemic stroke ,Cardiology ,Medicine ,Middle cerebral artery occlusion ,business ,Derivative (chemistry) - Published
- 2018
8. Lactoferrin induces cell surface retention of prion protein and inhibits prion accumulation
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Shirou Mohri, Takashi Yokoyama, Yuichi Tagawa, Yoshihisa Shimizu, Ryo Endo, Yuichi Murayama, Morikazu Imamura, Hiroshi Kitani, Yoshifumi Iwamaru, Hiroyuki Okada, Yuko Ushiki-Kaku, and Takato Takenouchi
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PrPSc Proteins ,Amyloid ,animal diseases ,media_common.quotation_subject ,Blotting, Western ,Cell ,Mice, Transgenic ,Biochemistry ,Mice ,Cellular and Molecular Neuroscience ,medicine ,Animals ,PrPC Proteins ,Internalization ,Cells, Cultured ,media_common ,chemistry.chemical_classification ,biology ,Lactoferrin ,Cell Membrane ,Flow Cytometry ,Virology ,nervous system diseases ,Cell biology ,medicine.anatomical_structure ,chemistry ,Cell culture ,Transferrin ,biology.protein ,Protein Misfolding Cyclic Amplification ,Cattle ,Glycoprotein ,Scrapie - Abstract
Prion diseases are fatal neurodegenerative disorders, and the conformational conversion of normal cellular prion protein (PrP(C)) into its pathogenic, amyloidogenic isoform (PrP(Sc)) is the essential event in the pathogenesis of these diseases. Lactoferrin (LF) is a cationic iron-binding glycoprotein belonging to the transferrin (TF) family, which accumulates in the amyloid deposits in the brain in neurodegenerative disorders, such as Alzheimer's disease and Pick's disease. In the present study, we have examined the effects of LF on PrP(Sc) formation by using cell culture models. Bovine LF inhibited PrP(Sc) accumulation in scrapie-infected cells in a time- and dose-dependent manner, whereas TF was not inhibitory. Bioassays of LF-treated cells demonstrated prolonged incubation periods compared with non-treated cells indicating a reduction of prion infectivity. LF mediated the cell surface retention of PrP(C) by diminishing its internalization and was capable of interacting with PrP(C) in addition to PrP(Sc). Furthermore, LF partially inhibited the formation of protease-resistant PrP as determined by the protein misfolding cyclic amplification assay. Our results suggest that LF has multifunctional antiprion activities.
- Published
- 2008
9. Surface-Initiated Graft Atom Transfer Radical Polymerization of Methyl Methacrylate from Chitin Nanofiber Macroinitiator under Dispersion Conditions
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Jun-ichi Kadokawa, Kazuya Yamamoto, and Ryo Endo
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macromolecular substances ,Biomaterials ,atom transfer radical polymerization ,chemistry.chemical_compound ,Chitin ,lcsh:TP890-933 ,Bromide ,lcsh:TP200-248 ,Polymer chemistry ,Methyl methacrylate ,lcsh:QH301-705.5 ,Civil and Structural Engineering ,methyl methacrylate ,Atom-transfer radical-polymerization ,Surface initiated ,surface-initiated graft polymerization ,food and beverages ,lcsh:Chemicals: Manufacture, use, etc ,lcsh:QC1-999 ,lcsh:Biology (General) ,chemistry ,Mechanics of Materials ,Nanofiber ,Ceramics and Composites ,lcsh:Textile bleaching, dyeing, printing, etc ,dispersion ,Methanol ,Dispersion (chemistry) ,lcsh:Physics ,chitin nanofiber - Abstract
Surface-initiated graft atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA) from self-assembled chitin nanofibers (CNFs) was performed under dispersion conditions. Self-assembled CNFs were initially prepared by regeneration from a chitin ion gel with 1-allyl-3-methylimidazolium bromide using methanol, the product was then converted into the chitin nanofiber macroinitiator by reaction with α-bromoisobutyryl bromide in a dispersion containing N,N-dimethylformamide. Surface-initiated graft ATRP of MMA from the initiating sites on the CNFs was subsequently carried out under dispersion conditions, followed by filtration to obtain the CNF-graft-polyMMA film. Analysis of the product confirmed the occurrence of the graft ATRP on the surface of the CNFs.
- Published
- 2015
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10. Stabilization of Kv1.5 channel protein by the inotropic agent olprinone
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Kumi Morikawa, Yasutaka Kurata, Junichiro Miake, Takehito Kondo, Katsumi Higaki, Ichiro Hisatome, Tomomi Notsu, Masanari Kuwabara, Haruaki Ninomiya, Akio Yoshida, Peili Li, Ryo Endo, Yasuaki Shirayoshi, Yoshimi Inagaki, Kazuhiro Yamamoto, and Kazuyoshi Ogura
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Cardiotonic Agents ,Pyridones ,Vasodilation ,complex mixtures ,Membrane Potentials ,Cell membrane ,symbols.namesake ,Kv1.5 Potassium Channel ,Olprinone ,Chlorocebus aethiops ,medicine ,Animals ,Pharmacology ,Membrane potential ,Dose-Response Relationship, Drug ,Chemistry ,Protein Stability ,Endoplasmic reticulum ,Imidazoles ,Phosphodiesterase ,Golgi apparatus ,medicine.anatomical_structure ,nervous system ,Biochemistry ,COS Cells ,symbols ,Biophysics ,Chemical chaperone - Abstract
Olprinone is an inotropic agent that inhibits phosphodiesterase (PDE) III and causes vasodilation. Olprinone has been shown to be less proarrhythmic and possibly affect expression of functional Kv1.5 channels that confer the ultra-rapid delayed-rectifier K+ channel current (IKur) responsible for action potential repolarization. To reveal involvement of Kv1.5 channels in the less arrhythmic effect of olprinone, we examined effects of the agent on the stability of Kv1.5 channel proteins expressed in COS7 cells. Olprinone at 30-1000 nM increased the protein level of Kv1.5 channels in a concentration-dependent manner. Chase experiments showed that olprinone delayed degradation of Kv1.5 channels. Olprinone increased the immunofluorescent signal of Kv1.5 channels in the endoplasmic reticulum (ER) and Golgi apparatus as well as on the cell surface. Kv1.5-mediated membrane currents, measured as 4-aminopyridine-sensitive currents, were increased by olprinone without changes in their activation kinetics. A protein transporter inhibitor, colchicine, abolished the olprinone-induced increase of Kv.1.5-mediated currents. The action of olprinone was inhibited by 4-aminopyridine, and was not mimicked by the application of 8-Bromo-cAMP. Taken together, we conclude that olprinone stabilizes Kv1.5 proteins at the ER through an action as a chemical chaperone, and thereby increases the density of Kv1.5 channels on the cell membrane. The enhancement of Kv1.5 currents could underlie less arrhythmogenicity of olprinone.
- Published
- 2015
11. Bacillus thuringiensis Cry1Ab, but not Cry1Aa or Cry1Ac, disrupts liposomes
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Ryo Endo, Takeshi Maruyama, Taisuke Kato, Yasuyuki Shitomi, Hidetaka Hori, Ryoichi Sato, Masahiro Higuchi, Toshiaki Mitsui, Kousuke Haginoya, and Tohru Hayakawa
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Liposome ,Health, Toxicology and Mutagenesis ,Vesicle ,fungi ,Phospholipid ,Midgut ,General Medicine ,Phosphatidylserine ,Biology ,Calcein ,chemistry.chemical_compound ,Biochemistry ,chemistry ,Membrane protein ,Phosphatidylcholine ,Biophysics ,Agronomy and Crop Science - Abstract
We evaluated the ability of Cry1Aa9, Cry1Ab4, and Cry1Ac1 insecticidal toxins from Bacillus thuringiensis to destroy liposomes. Cry1A toxins are thought to form pores in midgut apical cell membranes (BBMV), thereby disrupting midgut cells. Liposomes containing fluorescent calcein were prepared using phosphatidylcholine (PC) and phosphatidylserine (PS) (PC/PS-Liposomes) or PC alone (PC-Liposomes). Cry1Ab (1.4 μM), but not Cry1Aa or Cry1Ac, disrupted PC/PS-Liposomes and PC-Liposomes. PC/PS-Liposomes containing cholesterol and oligosaccharylceramide from Plutella xylostella midgut were damaged even more extensively by Cry1Ab, but the inclusion of either lipid alone had no effect. The initial velocity of Cry1Ab-mediated liposome disruption increased 17-fold when liposomes were prepared with Triton X-100-soluble proteins from Bombyx mori BBMV and PC (PC/Proteo-Liposomes), and Cry1Aa and Cry1Ac also caused slight disruption. These data suggest that Cry1Ab achieves higher penetration into PC/PS-Liposomes, PC-Liposomes, and PC/Proteo-Liposomes compared with Cry1Aa or Cry1Ac and that Cry1Ab may interact with membrane proteins.
- Published
- 2006
12. Growth Inhibition by Metabolites of γ-Hexachlorocyclohexane inSphingobium japonicumUT26
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Ryo Endo, Yuji Nagata, Yoshiyuki Ohtsubo, and Masataka Tsuda
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chemistry.chemical_classification ,Sphingomonas paucimobilis ,Molecular Structure ,biology ,Metabolite ,Organic Chemistry ,Mutant ,General Medicine ,Biodegradation ,biology.organism_classification ,Applied Microbiology and Biotechnology ,Biochemistry ,Analytical Chemistry ,Sphingomonadaceae ,chemistry.chemical_compound ,Enzyme ,chemistry ,Sphingobium japonicum ,Growth inhibition ,Molecular Biology ,Hexachlorocyclohexane ,Bacteria ,Cell Proliferation ,Biotechnology - Abstract
The growth of a gamma-hexachlorocyclohexane (gamma-HCH)-degrading bacterium Sphingobium japonicum (formerly Sphingomonas paucimobilis) UT26 in rich medium was inhibited by gamma-HCH. This growth inhibition was not observed in a mutant that lacked the initial or second step enzymatic activity for gamma-HCH degradation, suggesting that metabolites of gamma-HCH are toxic to UT26. Two metabolites of gamma-HCH, 2,5-dichlorophenol (2,5-DCP) and 2,5-dichlorohydroquinone (2,5-DCHQ), showed a direct toxic effect on UT26 and other sphingomonad strains. Because only 2,5-DCP accumulated during gamma-HCH degradation, 2,5-DCP is thought to be a main compound for growth inhibition.
- Published
- 2006
13. Simultaneous treatment with azelnidipine and olmesartan inhibits apoptosis of Hl-1 cardiac myocytes expressing E334k cMyBPC
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Nani Maharani, Peili Li, Ryo Endo, Haruaki Ninomiya, Sulistiyati Bayu Utami, Ichiro Hisatome, Sodiqur Rifqi, Kenshiro Yamamoto, Shinji Sakata, Udin Bahrudin, Akira Hasegawa, Mochamad Ali Sobirin, Yasuaki Shirayoshi, Nobuhito Ikeda, and Kumi Morikawa
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medicine.medical_specialty ,Dihydropyridines ,Azelnidipine ,bcl-X Protein ,Tetrazoles ,Apoptosis ,Pharmacology ,Mice ,Internal medicine ,Drug Discovery ,medicine ,Animals ,Myocytes, Cardiac ,Amlodipine ,Carvedilol ,Cells, Cultured ,biology ,Chemistry ,Cytochrome c ,Imidazoles ,General Medicine ,Calcium Channel Blockers ,Endocrinology ,Valsartan ,Proto-Oncogene Proteins c-bcl-2 ,Bepridil ,biology.protein ,Olmesartan ,Carrier Proteins ,Angiotensin II Type 1 Receptor Blockers ,Azetidinecarboxylic Acid ,medicine.drug - Abstract
Apoptosis appears to play an important role in the pathogenesis of hypertrophic cardiomyopathy (HCM). We have previously reported 3 HCM patients carrying the E334K MYBPC3, and that heterologous expression of E334K cMyBPC in cultured cells induced apoptosis. The purpose of this study was to identify pharmacological agents that would inhibit apoptosis in HL-1 cardiomyocytes expressing E334K cMyBPC.E334K cMyBPC expression in cells increased levels of pro-apoptosis (p53, Bax and cytochrome c) and decreased levels of anti-apoptosis (Bcl-2 and Bcl-XL). While the beta blocker carvedilol (1 μM) normalized the level of p53 and Bcl-2 and the calcium channel blocker (CCB) bepridil (0.5 μM) normalized that of Bcl-2, both the CCB azelnidipine (1 μM) and the angiotensin receptor blocker (ARB) olmesartan (10 μM) normalized those of p53, Bax, cytochrome c, and Bcl-XL. Among those proteins, cytochrome c was the one which showed the highest degree of change. Both azelnidipine (0.1 μM) and olmesartan (1 μM) reduced the level of cytochrome c by 40.2 ± 4.3% and 31.3 ± 5.1%, respectively. The CCB amlodipine and the ARB valsartan reduced it only by 19.1 ± 2.1% and 20.1 ± 5.2%, respectively. Flow cytometric analysis and annexin V staining showed that treatment of cells with azelnidipine (0.1 μM) plus olmesartan (0.3 μM) or that with amlodipine (0.1 μM) plus valsartan (0.3 μM) reduced the number of apoptotic cells by 35.8 ± 10.5% and 18.4 ± 3.2%, respectively.Azelnidipine plus olmesartan or amlodipine plus valsartan inhibited apoptosis of HL-1 cells expressing E334K cMyBPC, and the former combination was more effective than the latter.
- Published
- 2013
14. Aerobic degradation of lindane (gamma-hexachlorocyclohexane) in bacteria and its biochemical and molecular basis
- Author
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Masataka Tsuda, Yuji Nagata, Ryo Endo, Yoshiyuki Ohtsubo, and Michihiro Ito
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chemistry.chemical_classification ,Sphingomonas paucimobilis ,Insecticides ,Molecular Sequence Data ,Lyases ,General Medicine ,Biology ,biology.organism_classification ,Applied Microbiology and Biotechnology ,Aerobiosis ,Amino acid ,Sphingomonadaceae ,Plasmid ,Biodegradation, Environmental ,chemistry ,Biochemistry ,Sphingobium japonicum ,Amino Acid Sequence ,Insertion sequence ,Peptide sequence ,Gene ,Genome, Bacterial ,Hexachlorocyclohexane ,Biotechnology - Abstract
gamma-Hexachlorocyclohexane (gamma-HCH, also called gamma-BHC and lindane) is a halogenated organic insecticide that causes serious environmental problems. The aerobic degradation pathway of gamma-HCH was extensively revealed in bacterial strain Sphingobium japonicum (formerly Sphingomonas paucimobilis) UT26. gamma-HCH is transformed to 2,5-dichlorohydroquinone through sequential reactions catalyzed by LinA, LinB, and LinC, and then 2,5-dichlorohydroquinone is further metabolized by LinD, LinE, LinF, LinGH, and LinJ to succinyl-CoA and acetyl-CoA, which are metabolized in the citrate/tricarboxylic acid cycle. In addition to these catalytic enzymes, a putative ABC-type transporter system encoded by linKLMN is also essential for the gamma-HCH utilization in UT26. Preliminary examination of the complete genome sequence of UT26 clearly demonstrated that lin genes for the gamma-HCH utilization are dispersed on three large circular replicons with sizes of 3.5 Mb, 682 kb, and 191 kb. Nearly identical lin genes were also found in other HCH-degrading bacterial strains, and it has been suggested that the distribution of lin genes is mainly mediated by insertion sequence IS6100 and plasmids. Recently, it was revealed that two dehalogenases, LinA and LinB, have variants with small number of amino acid differences, and they showed dramatic functional differences for the degradation of HCH isomers, indicating these enzymes are still evolving at high speed.
- Published
- 2007
15. Partial characterization of monoclonal antibodies which bind to disease-associated prion protein in immunoprecipitaion assay
- Author
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Takuji Yamamoto, Takashi Yokoyama, Yuko Ushiki, Yoshihisa Shimizu, Shinkichi Irie, Shunji Hattori, Yoshifumi Iwamaru, and Ryo Endo
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Pathogenesis ,nervous system ,Biochemistry ,Chemistry ,medicine.drug_class ,animal diseases ,mental disorders ,medicine ,Prion protein ,Monoclonal antibody ,Molecular biology ,nervous system diseases - Abstract
Conformational conversion of cellular prion protein (PrPC) to scrapie-form prion protein (PrPSc) is thought to be the central event in prion pathogenesis. Several studies have shown that their distinct conformation should cause different immunogenic properties, however, almost all mAbs generated against PrP are unable to recognize each ones separately. Such characters of mAbs make it diffcult to study conformational difference between PrPC and PrPSc or mechanism of prion replication. Therefore the purpose of this study is to generate such mAbs that would react with PrPSc but not with PrPC.
- Published
- 2006
16. Phosphorylation of AATYK1 by Cdk5 Suppresses Its Tyrosine Phosphorylation
- Author
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Tetsuya Takano, Mitsunori Fukuda, Ryo Endo, Koji Tsutsumi, Mineko Tomomura, Toshio Ohshima, and Shin-ichi Hisanaga
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Cell Biology/Neuronal Signaling Mechanisms ,lcsh:Medicine ,Endosomes ,Protein tyrosine phosphatase ,Receptor tyrosine kinase ,MAP2K7 ,Mice ,chemistry.chemical_compound ,Cell Biology/Membranes and Sorting ,Chlorocebus aethiops ,Biochemistry/Cell Signaling and Trafficking Structures ,Neuroscience/Neuronal Signaling Mechanisms ,Animals ,Protein phosphorylation ,Phosphorylation ,lcsh:Science ,Cells, Cultured ,MAPK14 ,Neurons ,Multidisciplinary ,biology ,lcsh:R ,Brain ,Cyclin-Dependent Kinase 5 ,Tyrosine phosphorylation ,Protein-Tyrosine Kinases ,Molecular biology ,Cell biology ,src-Family Kinases ,nervous system ,chemistry ,COS Cells ,biology.protein ,Tyrosine ,lcsh:Q ,Apoptosis Regulatory Proteins ,Research Article ,Protein Binding ,Proto-oncogene tyrosine-protein kinase Src - Abstract
Apoptosis-associated tyrosine kinase 1 (AATYK1), a novel serine/threonine kinase that is highly expressed in the brain, is involved in neurite extension and apoptosis of cerebellar granule neurons; however, its precise function remains unknown. In this study, we investigated the interaction of AATYK1A with Cyclin-dependent kinase 5 (Cdk5)/p35, a proline-directed protein kinase that is predominantly expressed in neurons. AATYK1A bound to the p35 activation subunit of Cdk5 in cultured cells and in mouse brains and colocalized with p35 on endosomes in COS-7 cells. AATYK1A was phosphorylated at Ser34 by Cdk5/p35 in vitro, in cultured neurons and in mouse brain. In PC12D cells, Ser34 phosphorylation increased after treatment with nerve growth factor and phosphorylated AATYK1A accumulated in growth cones of PC12D cells. Ser34 phosphorylation suppressed the tyrosine phosphorylation of AATYK1A by Src family kinases. These results suggest a possibility that AATYK1A plays a role in early to recycling endosomes and its function is regulated by phosphorylation with Cdk5 or Src-family kinases.
- Published
- 2010
17. Pilot Plant Test on Manufacturing Hydroxylamine from Ammonium Sulfite, Nitrous Anhydride and Sulfer Dioxide
- Author
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Seiya Otani and Ryo Endo
- Subjects
Ammonium carbonate ,Embryology ,Aqueous solution ,Ammonium nitrate ,Inorganic chemistry ,Cell Biology ,chemistry.chemical_compound ,Ammonia ,Hydroxylamine ,chemistry ,Yield (chemistry) ,Ammonium ,Anatomy ,Ammonium sulfite ,Developmental Biology - Abstract
Based on the new research result obtained in the laboratory process of manufacturing hydroxylamine by three stages, oxidation of ammonia, absorption of nitrous anhydride gas by ammonium sulfite aqueous solution and reduction of the solution by sulfur dioxide, a pilot plant test was done and the following results were obtained.(1) The yield of hydroxylamine from ammonia in this process is 5-10% higher than that of the process in which ammonium carbonate solution is used as a solvent, and the amount of byproducts, ammonium nitrate and ammonium salt of sulfamic acid, is 2/3-1/2 of that in the latter process.(2) In the oxidation of ammonia, Pt-Rh catalyst showed the average yield of 86.4% and this yield affects the yield of the following absorption tower.(3) In the absorption of nitrous anhydride gas, the composition of the gas p is the important factor which affects the yield, and the analysis was done by using the constant of trimolecular reaction velocity observed by Bodenstein.As the results, it is observed that the oxidation of NO in the absorption tower can not be ignored and that the optimum p is less than 0.40.(4) In manufacturing hydroxylamine, the most effective factor is the Iodine value ratio of the absorved solvent, the optimum ratio of which is 21%.(5) The apparent heat of reaction between nitrous anhydride gas and ammonium sulfite solution in this process was measured and the average value of 34.7kcal/(NH4)2SO3mole was obtained.
- Published
- 1962
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