448 research outputs found
Recent progress in copper-catalyzed difunctionalization of unactivated carboncarbon multiple bonds
AbstractCopper-catalyzed difunctionalization of unactivated carboncarbon multiple bonds involving a carboncarbon bond formation process is reviewed. Carboamination, carbooxygenation, carboboration, and other difunctionalization reactions of alkenes, alkynes, and allenes are described
Targeting Receptor Tyrosine Kinases for Chemoprevention by Green Tea Catechin, EGCG
Tea is one of the most popular beverages consumed worldwide. Epidemiologic studies show an inverse relationship between consumption of tea, especially green tea, and development of cancers. Numerous in vivo and in vitro studies indicate strong chemopreventive effects for green tea and its constituents against cancers of various organs. (–)-Epigallocatechin-3-gallate (EGCG), the major catechin in green tea, appears to be the most biologically active constituent in tea with respect to inhibiting cell proliferation and inducing apoptosis in cancer cells. Recent studies indicate that the receptor tyrosine kinases (RTKs) are one of the critical targets of EGCG to inhibit cancer cell growth. EGCG inhibits the activation of EGFR (erbB1), HER2 (neu/erbB2) and also HER3 (neu/erbB3), which belong to subclass I of the RTK superfamily, in various types of human cancer cells. The activation of IGF-1 and VEGF receptors, the other members of RTK family, is also inhibited by EGCG. In addition, EGCG alters membrane lipid organization and thus inhibits the dimerization and activation of EGFR. Therefore, EGCG inhibits the Ras/MAPK and PI3K/Akt signaling pathways, which are RTK-related cell signaling pathways, as well as the activation of AP-1 and NF-κB, thereby modulating the expression of target genes which are associated with induction of apoptosis and cell cycle arrest in cancer cells. These findings are significant because abnormalities in the expression and function of RTKs and their downstream effectors play a critical role in the development of several types of human malignancies. In this paper we review evidence indicating that EGCG exerts anticancer effects, at least in part, through inhibition of activation of the specific RTKs and conclude that targeting RTKs and related signaling pathway by tea catechins might be a promising strategy for the prevention of human cancers
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An Analysis of Effects of Boredom on Revisit Intention – A Case in Japanese Popular Tourism Destinations
This study focuses on the effects of visitors’ boredom of a destination on their intention to revisit it, using two Japanese popular tourism destinations as the cases. Relationships between three factors, which are satisfaction, boredom and revisit intention, were examined. In addition to the subjective index of visitors’ boredom based on ratings on a scale, the rate of remaining facilities (RoRF), which was the objective index of visitors’ boredom, is also employed. A questionnaire survey was conducted to obtain data related to the five factors. We conclude that subjective index of visitors’ boredom may not be effective for understanding of their revisit intention, while their revisit intention can arguably be relevant to the RoRF
Petrology of Peridotite Xenoliths from Arcs as an Insight into Wedge-Mantle Processes
金沢大学大学院自然科学研究科Scedule:17-18 March 2003, Vemue: Kanazawa, Japan, Kanazawa Citymonde Hotel, Project Leader : Hayakawa, Kazuichi, Symposium Secretariat: XO kamata, Naoto, Edited by:Kamata, Naoto
Petrology and geochemistry of the mantle peridotite xenoliths from Tallante, southeast Spain : implications for mantle wedge materials and processes
取得学位:博士(理学),学位授与番号:博甲第738号,学位授与年月日:平成17年3月22
Development and experimental verification of a genome-scale metabolic model for Corynebacterium glutamicum
<p>Abstract</p> <p>Background</p> <p><it>In silico </it>genome-scale metabolic models enable the analysis of the characteristics of metabolic systems of organisms. In this study, we reconstructed a genome-scale metabolic model of <it>Corynebacterium glutamicum </it>on the basis of genome sequence annotation and physiological data. The metabolic characteristics were analyzed using flux balance analysis (FBA), and the results of FBA were validated using data from culture experiments performed at different oxygen uptake rates.</p> <p>Results</p> <p>The reconstructed genome-scale metabolic model of <it>C. glutamicum </it>contains 502 reactions and 423 metabolites. We collected the reactions and biomass components from the database and literatures, and made the model available for the flux balance analysis by filling gaps in the reaction networks and removing inadequate loop reactions. Using the framework of FBA and our genome-scale metabolic model, we first simulated the changes in the metabolic flux profiles that occur on changing the oxygen uptake rate. The predicted production yields of carbon dioxide and organic acids agreed well with the experimental data. The metabolic profiles of amino acid production phases were also investigated. A comprehensive gene deletion study was performed in which the effects of gene deletions on metabolic fluxes were simulated; this helped in the identification of several genes whose deletion resulted in an improvement in organic acid production.</p> <p>Conclusion</p> <p>The genome-scale metabolic model provides useful information for the evaluation of the metabolic capabilities and prediction of the metabolic characteristics of <it>C. glutamicum</it>. This can form a basis for the <it>in silico </it>design of <it>C. glutamicum </it>metabolic networks for improved bioproduction of desirable metabolites.</p
Origin of Spinal-Pyroxene Symplectite in Lherzolite Xenoliths from Tallante, Southeast Spain : Envidence for Mantle Diapirism beneath the betic-Rif Zone
金沢大学大学院自然科学研究科Promoting Environmental Pesearch in Pan-Japan Sea Area : Young Researchers\u27 Network, Schedule: March 8-10,2006,Kanazawa Excel Hotel Tokyu, Japan, Organized by: Kanazawa University 21st-Century COE Program, Environmental Monitoring and Prediction of Long- & Short- Term Dynamics of Pan-Japan Sea Area ; IICRC(Ishikawa International Cooperation Research Centre), Sponsors : Japan Sea Research ; UNU-IAS(United Nations University Institute of Advanced Studies)+Ishikawa Prefecture Government ; City of Kanazaw
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