26 results on '"Saijo R"'
Search Results
2. Fluorinated ß-Diketo Phosphorus Ylides Are Novel Inhibitors of the ABCB1 Efflux Pump of Cancer Cells
- Author
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Gabriella Spengler, Ocsovszki I, Ás, Tönki, Saijo R, Watanabe G, Kawase M, and Molnár J
3. The conversion of 3-deoxyarabinoheptulosonate 7-phosphate to 3-dehydroquinate by sorghum seedling preparations
- Author
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Saijo, R., primary and Kosuge, T., additional
- Published
- 1978
- Full Text
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4. Visions of Artificial Intelligence and Robots in Science Fiction: a computational analysis.
- Author
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Osawa H, Miyamoto D, Hase S, Saijo R, Fukuchi K, and Miyake Y
- Abstract
Driven by the rapid development of artificial intelligence (AI) and anthropomorphic robotic systems, the various possibilities and risks of such technologies have become a topic of urgent discussion. Although science fiction (SF) works are often cited as references for visions of future developments, this framework of discourse may not be appropriate for serious discussions owing to technical inaccuracies resulting from its reliance on entertainment media. However, these science fiction works could help researchers understand how people might react to new AI and robotic systems. Hence, classifying depictions of artificial intelligence in science fiction may be expected to help researchers to communicate more clearly by identifying science fiction elements to which their works may be similar or dissimilar. In this study, we analyzed depictions of artificial intelligence in SF together with expert critics and writers. First, 115 AI systems described in SF were selected based on three criteria, including diversity of intelligence, social aspects, and extension of human intelligence. Nine elements representing their characteristics were analyzed using clustering and principal component analysis. The results suggest the prevalence of four distinctive categories, including human-like characters, intelligent machines, helpers such as vehicles and equipment, and infrastructure, which may be mapped to a two-dimensional space with axes representing intelligence and humanity. This research contributes to the public relations of AI and robotic technologies by analyzing shared imaginative visions of AI in society based on SF works., Competing Interests: Conflict of interestThe authors declare that they have no conflict of interest., (© The Author(s) 2022.)
- Published
- 2022
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5. Indole-3-acetic acid synthesized through the indole-3-pyruvate pathway promotes Candida tropicalis biofilm formation.
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Miyagi M, Wilson R, Saigusa D, Umeda K, Saijo R, Hager CL, Li Y, McCormick T, and Ghannoum MA
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- Biofilms drug effects, Candida tropicalis drug effects, Candida tropicalis metabolism, Humans, Plant Growth Regulators pharmacology, Signal Transduction, Biofilms growth & development, Candida tropicalis growth & development, Candidiasis microbiology, Indoleacetic Acids pharmacology, Indoles metabolism
- Abstract
We previously found that the elevated abundance of the fungus Candida tropicalis is positively correlated with the bacteria Escherichia coli and Serratia marcescens in Crohn's disease patients and the three pathogens, when co-cultured, form a robust mixed-species biofilm. The finding suggests that these three pathogens communicate and promote biofilm formation, possibly through secretion of small signaling molecules. To identify candidate signaling molecules, we carried out a metabolomic analysis of the single-species and triple-species cultures of the three pathogens. This analysis identified 15 metabolites that were highly increased in the triple-species culture. One highly induced metabolite was indole-3-acetic acid (IAA), which has been shown to induce filamentation of certain fungi. We thus tested the effect of IAA on biofilm formation of C. tropicalis and demonstrated that IAA promotes biofilm formation of C. tropicalis. Then, we carried out isotope tracing experiments using 13C-labeled-tryptophan as a precursor to uncover the biosynthesis pathway of IAA in C. tropicalis. The results indicated that C. tropicalis synthesizes IAA through the indole-3-pyruvate pathway. Further studies using inhibitors of the indole-3-pyruvate pathway are warranted to decipher the mechanisms by which IAA influences biofilm formation., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2020
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6. Benzoxazole-Based Metal Complexes to Reverse Multidrug Resistance in Bacteria.
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Kincses A, Szabó S, Rácz B, Szemerédi N, Watanabe G, Saijo R, Sekiya H, Tamai E, Molnár J, Kawase M, and Spengler G
- Abstract
Bacteria often show resistance against antibiotics due to various mechanisms such as the expression of efflux pumps, biofilm formation, or bacterial quorum sensing (QS) controls. For successful therapy, the discovery of alternative agents is crucial. The objective of this study was to evaluate the efflux pump, anti-biofilm, and QS inhibiting, as well as antibacterial effects of 2-trifluoroacetonylbenzoxazole ligands ( 1-3 ) and their metal complexes ( 4-12 ) in bacteria. The ligand 2 and its Zn(II) complex 5 , and furthermore the Cu(II) complex 7 of ligand 1 , exerted remarkable antibacterial activity on the Staphylococcus aureus 272123 (MRSA) strain. In the minimum inhibitory concentration (MIC) reduction assay the ligand 3 , the Zn(II) complex 5 of ligand 2 , and the Cu(II), Ni(II), Mg(II), Fe(III) complexes ( 7 , 8 , 9 , 12 ) of ligand 1 enhanced the antibacterial activity of ciprofloxacin in MRSA. An increased ethidium bromide accumulation was detected for ligand 3 in MRSA while the Fe(III) complex 12 of ligand 1 decreased the biofilm formation of the reference S. aureus ATCC 25923 strain. The Zn(II) and Ag(II) complexes ( 3 and 4 ) of ligand 1 and ligand 3 inhibited the QS. Based on our results, the ligands and their metal complexes could be potential alternative drugs in the treatment of infectious diseases.
- Published
- 2020
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7. Metabolic Profiling of the Cerebrospinal Fluid in Pediatric Epilepsy.
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Akiyama T, Saigusa D, Hyodo Y, Umeda K, Saijo R, Koshiba S, and Kobayashi K
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- Adolescent, Anticonvulsants therapeutic use, Case-Control Studies, Child, Child, Preschool, Epilepsy drug therapy, Epilepsy metabolism, Female, Gas Chromatography-Mass Spectrometry, Humans, Infant, Infant, Newborn, Male, Vitamin B 6 cerebrospinal fluid, Epilepsy cerebrospinal fluid, Metabolome
- Abstract
To characterize metabolic profiles within the central nervous system in epilepsy, we performed gas chromatography-tandem mass spectrometry (GC-MS/MS)-based metabolome analysis of the cerebrospinal fluid (CSF) in pediatric patients with and without epilepsy. The CSF samples obtained from 64 patients were analyzed by GC-MS/MS. Multivariate analyses were performed for two age groups, 0-5 years of age and 6-17 years of age, to elucidate the effects of epilepsy and antiepileptic drugs on the metabolites. In patients aged 0-5 years (22 patients with epilepsy, 13 without epilepsy), epilepsy patients had reduced 2-ketoglutaric acid and elevated pyridoxamine and tyrosine. In patients aged 6-17 years (12 with epilepsy, 17 without epilepsy), epilepsy patients had reduced 1,5-anhydroglucitol. Valproic acid was associated with elevated 2-aminobutyric acid, 2-ketoisocaproic acid, 4-hydroxyproline, acetylglycine, methionine, N-acetylserine, and serine. Reduced energy metabolism and alteration of vitamin B6 metabolism may play a role in epilepsy in young children. The roles of 1,5-anhydroglucitol in epilepsy in older children and in levetiracetam and zonisamide treatment remain to be explained. Valproic acid influenced the levels of amino acids and related metabolites involved in the metabolism of serine, methionine, and leucine., Competing Interests: No potential conflict of interest relevant to this article was reported.
- Published
- 2020
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8. On the Electronic Nature of Bis((Z)-1-(benzo[d]oxazol-2-yl)-3.3.3-trifluoroprop-1-en-2-ate)palladium.
- Author
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May KL, Watanabe G, Saijo R, Kawase M, and Gossage RA
- Subjects
- Electrons, Halogenation, Ligands, Magnetic Resonance Spectroscopy, Quantum Theory, Spectrophotometry, Infrared, Benzoxazoles chemistry, Coordination Complexes chemistry, Palladium chemistry
- Abstract
The electronic nature of the recently reported complex, bis((Z)-1-(benzo[d]oxazol-2-yl)-3.3.3-trifluoroprop-1-en-2-ate)palladium, is re-investigated by a combination of spectroscopy (NMR, IR, magnetic moment, etc.) and Density Functional Theory (DFT: B3LYP 6-31G*/LANL2DZ). In contrast to the recent report, the title complex displays all the properties of diamagnetism and hence retains the properties of a formally Pd(II) square planar complex with a bis-κ
2 -N,O-donor ligand set. A modified synthetic route is also presented which improves the yield of the compound.- Published
- 2019
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9. Benzoxazole-based Zn(II) and Cu(II) Complexes Overcome Multidrug-resistance in Cancer.
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Spengler G, Kincses A, Rácz B, Varga B, Watanabe G, Saijo R, Sekiya H, Tamai E, Maki J, Molnár J, and Kawase M
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- ATP Binding Cassette Transporter, Subfamily B genetics, ATP Binding Cassette Transporter, Subfamily B metabolism, Animals, Cell Line, Tumor, Coordination Complexes chemistry, Copper chemistry, Drug Resistance, Multiple, Drug Resistance, Neoplasm, Lymphoma, T-Cell genetics, Lymphoma, T-Cell metabolism, Mice, Transfection, Zinc chemistry, Coordination Complexes pharmacology, Copper pharmacology, Lymphoma, T-Cell drug therapy, Zinc pharmacology
- Abstract
Background/aim: Multidrug resistance (MDR) represents a significant impediment to successful cancer treatment. In this study, novel metal [Zn(II), Cu(II), Mg(II), Ni(II), Pd(II), and Ag(I)] complexes of 2-trifluoroacetonylbenzoxazole previously synthesized and characterized by our group were tested for their MDR-reversing activity in comparison with the free ligands in L5178Y mouse T-lymphoma (MDR) cells transfected with human ATP-binding cassette sub-family B member 1 (ABCB1; P-glycoprotein) gene., Materials and Methods: Cytotoxic and antiproliferative effects of the complexes were assessed by the thiazolyl blue tetrazolium bromide (MTT) method. Modulation of ABCB1 activity was measured by rhodamine 123 accumulation assay using flow cytometry. The apoptosis-inducing activity of some complexes was also tested on the multidrug resistant L5178Y mouse T-lymphoma cells, using the annexin-V/propidium iodide assay., Results: When compared to the free ligand, a remarkable enhancement in MDR reversal and cytotoxic activity was found for the Zn(II) and Cu(II) complexes. The activity of the complexes proved to be up to 29- and 5-fold higher than that of the ligands and the ABCB1 inhibitor verapamil as positive control, respectively. The complexes possessed a remarkable potential to induce apoptosis of MDR cells., Conclusion: Our results suggest that the Zn(II) and Cu(II) complexes display significant MDR-reversing activity in a dose-dependent manner and possess strong cytotoxic activity and a remarkable potential to induce apoptosis in MDR L5178Y mouse T-lymphoma cells., (Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)
- Published
- 2018
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10. Synthesis and Antimicrobial Activity of 2-Trifluoroacetonylbenzoxazole Ligands and Their Metal Complexes.
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Watanabe G, Sekiya H, Tamai E, Saijo R, Uno H, Mori S, Tanaka T, Maki J, and Kawase M
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- Anti-Bacterial Agents chemistry, Benzoxazoles metabolism, Dose-Response Relationship, Drug, Ligands, Microbial Sensitivity Tests, Molecular Structure, Organometallic Compounds chemistry, Structure-Activity Relationship, Anti-Bacterial Agents chemical synthesis, Anti-Bacterial Agents pharmacology, Benzoxazoles chemistry, Organometallic Compounds chemical synthesis, Organometallic Compounds pharmacology, Pseudomonas aeruginosa drug effects
- Abstract
Three 2-fluoroacetonylbenzoxazole ligands 1a-c and their new Zn(II) complexes 2a-c have been synthesized. In addition, syntheses of new metal [Mg(II), Ni(II), Cu(II), Pd(II), and Ag(I)] complexes from 1a have been also described. The molecular and crystal structures of six metal complexes 2b and 2d-h were determined by single-crystal X-ray diffraction analyses. Their antibacterial activities against six Gram-positive and six Gram-negative bacteria were evaluated by minimum inhibitory concentrations (MIC), which were compared with those of appropriate antibiotics and silver nitrate. The results indicate that some metal compounds have more antibacterial effects in comparison with free ligands and have preferred antibacterial activities that may have potential pharmaceutical applications. Noticeably, the Ag(I) complex 2h exhibited low MIC value of 0.7 µM against Pseudomonas aeruginosa, which was even superior to the reference drug, Norfloxacin with that of 1.5 µM. Against P. aeruginosa, 2h is bacteriostatic, exerts the cell surface damage observed by scanning electron microscopy (SEM) and is less likely to develop resistance. The new 2h has been found to display effective antimicrobial activity against a series of bacteria.
- Published
- 2018
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11. A Novel Methodology for Synthesis of 1,5,6-Trisubstituted 2(1H)-Pyrazinones of Biological Interest.
- Author
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Saijo R, Sekiya H, Tamai E, Kurihara KI, Maki J, Sakagami H, and Kawase M
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- Anti-Bacterial Agents chemistry, Antineoplastic Agents chemistry, Cell Line, Cell Survival drug effects, Dose-Response Relationship, Drug, Drug Screening Assays, Antitumor, Gram-Negative Bacteria drug effects, Gram-Positive Bacteria drug effects, Humans, Microbial Sensitivity Tests, Molecular Structure, Pyrazines chemistry, Structure-Activity Relationship, Anti-Bacterial Agents chemical synthesis, Anti-Bacterial Agents pharmacology, Antineoplastic Agents chemical synthesis, Antineoplastic Agents pharmacology, Chemistry Techniques, Synthetic, Pyrazines chemical synthesis, Pyrazines pharmacology
- Abstract
In this report, we describe a new method for the synthesis of densely functionalized 2(1H)-pyrazinones. Treatment of mesoionic 1,3-oxazolium-5-olates with carbanions derived from activated methylene isocyanides (p-toluenesulfonylmethyl isocyanide (TosMIC) and ethyl isocyanoacetate) causes a novel ring transformation affording 2(1H)-pyrazinones in moderate to high yields. The cytotoxicity and antibacterial activity of some of the obtained products were studied and some of the products exhibited tumor-specific cytotoxicity.
- Published
- 2017
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12. Theaflavin Synthesized in a Selective, Domino-Type, One-Pot Enzymatic Biotransformation Method with Camellia sinensis Cell Culture Inhibits Weight Gain and Fat Accumulation to High-Fat Diet-Induced Obese Mice.
- Author
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Takemoto M, Takemoto H, and Saijo R
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- Animals, Biotransformation, Diet, High-Fat, Intra-Abdominal Fat drug effects, Male, Mice, Inbred C57BL, Peroxidases metabolism, Plant Extracts chemistry, Plant Leaves chemistry, Plant Leaves cytology, Plant Leaves metabolism, Weight Gain drug effects, Biflavonoids biosynthesis, Biflavonoids chemistry, Biflavonoids therapeutic use, Camellia sinensis chemistry, Camellia sinensis cytology, Camellia sinensis metabolism, Catechin biosynthesis, Catechin chemistry, Catechin therapeutic use, Obesity drug therapy
- Abstract
The polyphenolic compound theaflavin, which is the main red pigment present in black tea, is reported to elicit various physiological effects. Because of the extremely low concentration of theaflavin present in black tea, its extraction from black tea leaves in quantities sufficient for use in medical studies has been difficult. We have developed a simple, inexpensive, selective, domino-type, one-pot enzymatic biotransformation method for the synthesis of theaflavin that is suitable for use in medical studies. Subsequent administration of this synthetic theaflavin to high-fat diet-induced obese mice inhibited both body weight gain and visceral fat accumulation, with no significant difference in the amount of faeces between the experimental and control mice.
- Published
- 2016
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13. Synthesis and structures of stable phosphorus zwitterions derived from mesoionic 4-trifluoroacetyl-1,3-oxazolium-5-olates.
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Saijo R, Uno H, Mori S, and Kawase M
- Abstract
Trialkyl phosphites were evaluated as phosphorus nucleophiles for addition to mesoionic 4-trifluoroacetyl-1,3-oxazolium-5-olates (1), thereby producing tetravalent phosphorus zwitterions (2) in good yields. The structure of 2 was determined to be a tetravalent phosphonium enolate via single crystal X-ray analysis.
- Published
- 2016
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14. Fluorinated Beta-diketo Phosphorus Ylides Are Novel Efflux Pump Inhibitors in Bacteria.
- Author
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Kincses A, Szabó ÁM, Saijo R, Watanabe G, Kawase M, Molnár J, and Spengler G
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- Bacterial Outer Membrane Proteins antagonists & inhibitors, Bacterial Outer Membrane Proteins genetics, Bacterial Outer Membrane Proteins metabolism, Drug Resistance, Multiple, Bacterial genetics, Escherichia coli genetics, Escherichia coli metabolism, Escherichia coli Proteins genetics, Escherichia coli Proteins metabolism, Fluorometry methods, Gene Deletion, Gene Expression Regulation, Bacterial drug effects, Hydrocarbons, Fluorinated chemistry, Lipoproteins antagonists & inhibitors, Lipoproteins genetics, Lipoproteins metabolism, Membrane Transport Proteins genetics, Membrane Transport Proteins metabolism, Multidrug Resistance-Associated Proteins genetics, Multidrug Resistance-Associated Proteins metabolism, Quorum Sensing drug effects, Quorum Sensing genetics, Drug Resistance, Multiple, Bacterial drug effects, Escherichia coli drug effects, Escherichia coli Proteins antagonists & inhibitors, Hydrocarbons, Fluorinated pharmacology, Multidrug Resistance-Associated Proteins antagonists & inhibitors
- Abstract
Background: One of the most important resistance mechanisms in bacteria is the increased expression of multidrug efflux pumps. To combat efflux-related resistance, the development of new efflux pump inhibitors is essential., Materials and Methods: Ten phosphorus ylides were compared based on their MDR-reverting activity in multidrug efflux pump system consisting of the subunits acridine-resistance proteins A and B (AcrA and AcrB) and the multidrug efflux pump outer membrane factor TolC (TolC) of Escherichia coli K-12 AG100 strain and its AcrAB-TolC-deleted strain. Efflux inhibition was assessed by real-time fluorimetry and the inhibition of quorum sensing (QS) was also investigated. The relative gene expression of efflux QS genes was determined by real-time reverse transcriptase quantitative polymerase chain reaction., Results: The most potent derivative was Ph
3 P=C(COC2 F5 )CHO and its effect was more pronounced on the AcrAB-TolC-expressing E. coli strain, furthermore the most active compounds, Ph3 P=C(COCF3 )OMe, Ph3 P=C(COC2 F5 )CHO and Ph3 P=C(COCF3 )COMe, reduced the expression of efflux pump and QS genes., Conclusion: Phosphorus ylides might be valuable EPI compounds to reverse efflux related MDR in bacteria., (Copyright © 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.)- Published
- 2016
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15. Fluorinated β-Diketo Phosphorus Ylides Are Novel Inhibitors of the ABCB1 Efflux Pump of Cancer Cells.
- Author
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Spengler G, Ocsovszki I, Tönki ÁS, Saijo R, Watanabe G, Kawase M, and Molnár J
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- ATP Binding Cassette Transporter, Subfamily B antagonists & inhibitors, Animals, Drug Resistance, Multiple drug effects, Drug Resistance, Neoplasm drug effects, Flow Cytometry, Heterocyclic Compounds chemistry, Humans, Hydrocarbons, Fluorinated chemistry, Mice, Tumor Cells, Cultured, Vasodilator Agents pharmacology, Verapamil pharmacology, Cell Proliferation drug effects, Heterocyclic Compounds pharmacology, Hydrocarbons, Fluorinated pharmacology, Lymphoma, T-Cell drug therapy, Lymphoma, T-Cell pathology, Phosphorus chemistry
- Abstract
Efflux pump inhibitors are attractive compounds that reverse multidrug resistance (MDR) in cancer cells. In the present study, 10 phosphorus ylides (P-ylides) were compared based on their MDR-reverting activity in human ATP-binding cassette sub-family B member 1 (ABCB1; P-glycoprotein) gene-transfected L5178Y mouse T-lymphoma cells. Among them, three P-ylides, Ph3P=C(COCF3)COPh, Ph3P=C(COC2F5)COPh and Ph3P=C(COC3F7)COPh were identified as selectively modulating the ABCB1 pump. These compounds, with low cytotoxicity against mouse T-lymphoma cells, exhibited more potency than the positive control ABCB1 inhibitor verapamil., (Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.)
- Published
- 2015
16. New synthesis of 3-trifluoromethylpyrroles by condensation of mesoionic 4-trifluoroacetyl-1,3-oxazolium-5-olates with phosphorus ylides.
- Author
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Saijo R, Hagimoto Y, and Kawase M
- Subjects
- Acetylation, Ions chemistry, Methylation, Molecular Structure, Fluorine Compounds chemical synthesis, Oxazoles chemistry, Phosphorus chemistry, Pyrroles chemical synthesis
- Abstract
Mesoionic 4-trifluoroacetyl-1,3-oxazolium-5-olates (1), obtained from the reaction of N-acyl-N-alkylglycines with trifluoroacetic anhydride, react with phosphorus ylides to give β-trifluoromethylpyrroles (2) in good yields. The novel ring transformations of 1 into 2 occur via an initial attack of the ylide anions on the C-2 position of the ring.
- Published
- 2010
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17. The effects of O-substituents of hexahomotrioxacalix[3]arene on potentiometric discrimination between dopamine and biological organic/inorganic cations.
- Author
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Saijo R, Murakami H, Tsunekawa S, Imanishi S, Shirai N, Ikeda S, and Odashima K
- Subjects
- Molecular Structure, Calixarenes chemistry, Cations chemistry, Dopamine chemistry, Potentiometry methods
- Abstract
As an interesting type of molecular recognition at a membrane surface, the tri-O-acetic acid ester (host 2) of hexahomotrioxacalix[3]arene, when incorporated into poly(vinyl chloride) (PVC) liquid membranes, displays a high potentiometric selectivity for dopamine over, not only other catecholamines (noradrenaline, adrenaline), but also quaternary ammonium guests (tetramethylammonium, choline, and acetylcholine) and inorganic cations (Na+, K+, NH4+). Interestingly, changes in membrane potential based on the host-guest complexation of host 2 that were observed dopamine/inorganic cation selectivity were not displayed by the related hosts 3 and 4, which contain amide substituents. This paper describes our efforts to separately estimate the two factors contributing to the dopamine selectivities, i.e., the guest lipophilicity factor and the host-guest complexation factor, in an attempt to understand the effects of the O-substituents of these hosts. The potentiometric experiments showed that, although the guests had roughly equal lipophilicity, the electromotive force (EMF) response for dopamine by host 2 was excellent. Furthermore, host 2 displayed ca. a 20-fold stronger complexation for dopamine, compared to noradrenaline, adrenaline, K+, and NH4+ cations. These results indicate that the high potentiometric selectivity of the ion-selective electrode for dopamine mainly reflect, not the guest lipophilicity factor but the host-guest complexation factor. On the other hand, host 3 displayed ca. a 3000-fold stronger binding to Na+ than dopamine, thus explaining the reasons for the lower dopamine-selectivities of host 3 compared to host 2. It is interesting to note that the high potentiometric selectivities for dopamine were displayed by not only host 2 but also host 5, regardless of the simple structure of the O-substituents.
- Published
- 2007
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18. Dopamine-selective potentiometric responses by new ditopic sensory elements based on a hexahomotrioxacalix[3]arene.
- Author
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Saijo R, Tsunekawa S, Murakami H, Shirai N, Ikeda S, and Odashima K
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- Indicators and Reagents, Kinetics, Magnetic Resonance Spectroscopy, Membrane Potentials, Membranes, Artificial, Polyvinyl Chloride, Potentiometry, Biosensing Techniques, Calixarenes chemistry, Dopamine analysis
- Abstract
New ditopic sensory elements 2 and 3 for catecholamines based on a hexahomotrioxacalix[3]arene, with a boronic acid substituent appended, were designed and synthesized. As an interesting mode of molecular recognition at membrane surfaces, the host, when incorporated into poly(vinyl chloride) (PVC) liquid membranes, displayed excellent potentiometric selectivity for dopamine over other catecholamines (noradrenaline and adrenaline) and inorganic cations (Na+, K+, and NH4+).
- Published
- 2007
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19. Particle deposition of therapeutic aerosols in the nose and paranasal sinuses after transnasal sinus surgery: a cast model study.
- Author
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Saijo R, Majima Y, Hyo N, and Takano H
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- Administration, Intranasal, Administration, Topical, Aerosols administration & dosage, Air Movements, Humans, Nose, Paranasal Sinuses, Endoscopy methods, Models, Theoretical, Otorhinolaryngologic Surgical Procedures methods, Sinusitis surgery
- Abstract
Background: The topical administration of steroids or antibiotics to the nose and the sinuses is one of the important postsurgical therapies of endoscopic sinus surgery (ESS)., Methods: To investigate the effective deposition of aerosols in the paranasal sinuses after ESS, we restored the human nasosinus model that underwent ESS and studied the particle depositions on the ostiomeatal complex (OMC), maxillary, and ethmoid sinuses quantitatively., Results: A 45 degree nozzle insertion angle significantly increased the particle depositions more than the 30 degree angle (p < 0.05). A computer simulation-assisted analysis shows that the inertial deposition at OMC increased with a nozzle angle of 45 degrees versus 30 degrees. The particles with 5.63 microm in diameter significantly deposit on OMC and maxillary sinus compared with the particles with 16.37 microm (p < 0.05)., Conclusion: The topical administration of drugs to the paranasal sinuses postoperatively must be performed in consideration with aerodynamics of aerosols.
- Published
- 2004
20. Novel function of rare catechin, epigallocatechin-3-(3''-O-methyl)gallate, against cold injury in primary rat hepatocytes.
- Author
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Kagaya N, Hara Y, Saijo R, Kamiyoshi A, Tagawa Y, Kawase M, and Yagi K
- Abstract
Epigallocatechin-3-(3''-O-methyl)gallate (EGCg-3''-OMe) is a rare component in green tea leaf and its bioactivity is hardly known. In this paper, we report that EGCg-3''-OMe has the function for cold preservation of primary rat hepatocytes. Confluent primary cultured hepatocytes were suspended in a storage solution, culture medium or cell banker (CB). EGCg-3''-OMe was tested as a supplement in the storage solution together with a general cryoprotectant, dimethylsulfoxide (DMSO). After 24 h cold preservation of cells at 4 degrees C followed by 1 h rewarming, cell viability and urea-synthesizing activity, one of the most important liver functions, were measured. EGCg-3''-OMe dose-dependently maintained cell viability and this effect was equal to that of a commercial CB at the highest concentration. Cell viability was also maintained after a further 24 h incubation at 37 degrees C of the cold-preserved hepatocytes. Conversely, urea-synthesizing activity was dose-dependently reduced by EGCg-3''-OMe. Cell protection by EGCg-3''-OMe due to the decrease in metabolic activity in cold-preserved cells was suggested. The decreased hepatic function of cells caused by EGCg-3''-OMe was rescued after a further 24 h incubation of cells at 37 degrees C.
- Published
- 2003
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21. Suppression of cytotoxin-induced cell death in isolated hepatocytes by tea catechins.
- Author
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Kagaya N, Tagawa Y, Nagashima H, Saijo R, Kawase M, and Yagi K
- Subjects
- Animals, Caspase 3, Caspases biosynthesis, Cell Death drug effects, Cell Survival drug effects, Cells, Cultured, Enzyme Induction, Hepatocytes cytology, In Vitro Techniques, Male, Rats, Rats, Sprague-Dawley, Bromobenzenes toxicity, Catechin analogs & derivatives, Catechin pharmacology, Hepatocytes drug effects, Mycotoxins toxicity, Protective Agents pharmacology, Tea
- Abstract
To elucidate the hepatoprotective effects of green tea catechins, the following experiments were conducted utilizing (-)-epigallocatechin-3-gallate (EGCG), the major component of green tea catechin, together with other catechins. The protective effects of catechins against hepatotoxins, bromobenzene or rubratoxin B, were examined in primary cultures of rat hepatocytes. Bromobenzene and rubratoxin B are known to induce necrosis and apoptosis of cells, respectively. After 24-h treatment with toxin, EGCG and (-)-epigallocatechin-3-(3"-O-methyl)gallate (EGCg-3"-OMe) suppressed the bromobenzene-induced morphological change and dose-dependently prevented bromobenzene-induced cell death. Both catechins also prevented apoptotic cell death caused by rubratoxin B. In rubratoxin B-treated cells, both catechins were found to suppress the activation of caspase-3 by rubratoxin B. The results in the present study suggest that EGCG and EGCg-3"-OMe are potent hepatoprotective agents. This report is the first to show that catechins suppress cytotoxin-induced cell death.
- Published
- 2002
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22. Antioxidative activity of (-)-epigallocatechin-3-(3''-O-methyl)gallate isolated from fresh tea leaf and preliminary results on its biological activity.
- Author
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Kawase M, Wang R, Shiomi T, Saijo R, and Yagi K
- Subjects
- Animals, Antioxidants chemistry, Antioxidants isolation & purification, Catechin analogs & derivatives, Catechin chemistry, Catechin isolation & purification, Liver Neoplasms, Experimental pathology, Rats, Tumor Cells, Cultured, Antioxidants pharmacology, Catechin pharmacology, Tea chemistry
- Abstract
Antioxidative activity of (-)-epigallocatechin-3-(3''-O-methyl)gallate (catechin e) was examined. Catechin e showed a strong antioxidative activity. A preliminary test using rat cancer cells suggests that catechin e also has a strong cytotoxic activity. Among tested catechins, only catechin e has strong activity for both.
- Published
- 2000
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23. Changes caused by included enzymes in the constituents of Solanum nigrum berries.
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Yoshida K, Yahara S, Saijo R, Murakami K, Tomimatsu T, and Nohara T
- Subjects
- Plant Extracts analysis, Plants, Medicinal enzymology, Solanaceous Alkaloids isolation & purification
- Published
- 1987
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24. Tannins and related compounds. LXXXIV. Isolation and characterization of five new hydrolyzable tannins from the bark of Mallotus japonicus.
- Author
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Saijo R, Nonaka G, and Nishioka I
- Subjects
- Anti-Ulcer Agents analysis, Japan, Tannins analysis, Anti-Ulcer Agents isolation & purification, Plants, Medicinal analysis, Tannins isolation & purification
- Abstract
A chemical examination of the bark of Mallotus japonicus (Thunb.) Mueller-Arg. (Euphorbiaceae) has led to the isolation of five new hydrolyzable tannins (16-20), together with fourteen known tannins (1-14). On the basis of chemical and spectroscopic evidence, the structures of compounds 16 and 17 were established as 1,2-di-O-galloyl-3,6-(R)-hexahydroxydiphenoyl-beta-D-glucose and 1-O-digalloyl-3,6-(R)-hexahydroxydiphenoyl-beta-D-glucose, respectively, while compounds 18 (mallojaponin) and 19 (mallonin) were shown to be 1-O-galloyl-2,4-elaeocarpusinoyl-3,6-(R)-valoneayl-bet a-D-glucose and 1-O-galloyl-2,4-elaeocarpusinoyl-beta-D-glucose. Compound 20 (mallotusinin) was characterized as a novel ellagitannin which possesses a unique 1,1'-(3,3',4,4'-tetrahydroxy)dibenzofurandicarboxyl group. On the other hand, examination of the leaves revealed the presence of hydrolyzable tannins (8-10, 12-15) all containing a beta-D-glucopyranose core with 1C4-conformation. Furthermore, the orientation of the valoneayl group in mallotinic acid (13) and mallotusinic acid (14), which had remained unclarified, was determined on the basis of 1H-13C shift correlation spectral analysis and chemical correlations.
- Published
- 1989
- Full Text
- View/download PDF
25. [Studies on the constituents of Solanum plants. II. On the constituents of the immature berries of Solanum nigrum L. (author's transl)].
- Author
-
Saijo R, Murakami K, Nohara T, Tomimatsu T, Sato A, and Matsuoka K
- Subjects
- Antineoplastic Agents, Phytogenic, Cells, Cultured, Chemical Phenomena, Chemistry, Glycosides pharmacology, Humans, Structure-Activity Relationship, Glycosides isolation & purification, Plants, Medicinal analysis, Solanaceous Alkaloids analysis
- Published
- 1982
- Full Text
- View/download PDF
26. [Studies on the constituents of Solanum plants. I. On the constituents of the stem parts of Solanum lyratum Thunb (author's transl)].
- Author
-
Murakami K, Saijo R, Nohara T, and Tomimatsu T
- Subjects
- Chemical Phenomena, Chemistry, Chemistry, Physical, Glycosides isolation & purification, Plants, Medicinal analysis
- Published
- 1981
- Full Text
- View/download PDF
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