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71.
72.
R Baba Y Hori S Mizukami K Kikuchi 《Journal of the American Chemical Society》2012,134(35):14310-14313
Histone deacetylases (HDACs) are key enzymatic regulators of many cellular processes such as gene expression, cell cycle, and tumorigenesis. These enzymes are attractive targets for drug development. However, very few simple methods for monitoring HDAC activity have been reported. Here, we have developed a fluorogenic probe, K4(Ac)-CCB, which consists of the histone H3 peptide containing acetyl-Lys and a coumarin fluorophore with a carbonate ester. By the simple addition of the probe to a HDAC solution, enzyme activity was clearly detected through spontaneous intramolecular transesterification, which renders the probe fluorescent. In addition, K4(Ac)-CCB can be applied to the evaluation of HDAC inhibitor activity. This is the first report to demonstrate the monitoring of HDAC activity by using a one-step procedure. Thus, our novel fluorogenic probe will provide a powerful tool for epigenetic research and the discovery of HDAC-targeted drugs. 相似文献
73.
Tetsuyuki Taniai Sachiko Wakasugi Susumu Hashimoto Ai Shimada Tatsuya Urabe Kazuya Takahashi 《International journal of environmental analytical chemistry》2013,93(5):601-612
To obtain information on the environmental impact of materials eluted from volcanic ashes of Mt. Oyama, Miyake Island, which erupted in July 2000, the dissolution behaviours of heavy metals and rare-earth elements from the volcanic ashes were examined. The most important characteristic of the Mt. Oyama eruption is that sulphur dioxide (SO2) gas has been continuously released, and all persons living on Miyake Island have been required to evacuate. To estimate in terms of the volcanic eruption using SO2 gas, the ash nature in Mt. Usu, Hokkaido, was also examined and compared with that in Mt. Oyama. When rain water mixed the ashes, the water from the ashes of Mt. Oyama became acidic because of the sulphuric acid. Therefore, SO2 gas in Mt. Oyama can accelerate the dissolution of protons and heavy metals in the ashes, whereas the rain water in Mt. Usu was not acidic and the dissolution of the heavy metals was not so evident compared with that in the case of Mt. Oyama. With this sulphuric acid, heavy metals such as As, Cd, Pb and Hg in the ashes in Mt. Oyama easily dissolved owing to the low pH. The ashes in Mt. Oyama had been released for eight years and the amount of fallen ashes was estimated to be 33 billion tons. The weights of the harmful heavy metals in the volcanic ashes, such as As, Cd, Pb and Hg, were estimated to be 3.8?×?102, 1.3?×?103, 1.1?×?103 and 29?kg, respectively, and these heavy metals were dissolved and diluted in seawater. Therefore, the concentration and species (chemical form) of these metals should be carefully monitored in the future. Moreover, SO2 gas, which has a direct effect on human health and has been monitored continuously, causes other effects, such as facilitation of metal ion elution and rock aeration. 相似文献
74.
75.
Keika Hattori Kazuya Yamaguchi Junichiro Yamaguchi Kenichiro Itami 《Tetrahedron》2012,68(37):7605-7612
The palladium- and copper-catalyzed C–H arylation reactions of 1H- and 2H-indazoles with haloarenes are described. A PdCl2/phen/Ag2CO3/K3PO4 catalytic system is effective for the C–H arylation of 1H- and 2H-indazoles with haloarenes, whereas a less expensive CuI/phen/LiOt-Bu catalytic system is applicable to the C–H coupling of substituted 2H-indazoles and iodoarenes. The utility of newly developed catalyst was demonstrated in the rapid synthesis of YC-1 (an antitumor agent) and YD-3 (platelet anti-aggregating agent). These new reactions represent important direct functionalization tools of indazoles, well-known bioisosteres of pharmaceutically important indole core. 相似文献
76.
Feroza Begum Yoshinori Namihira S. M. Abdur Razzak Shubi F. Kaijage Nguyen H. Hai Kazuya Miyagi Hiroki Higa Nianyu Zou 《Optical Review》2009,16(2):54-58
This research presents a simple index-guiding square photonic crystal fibers (SPCFs) that has a silica core surrounded by
air hole with two different diameters. It is demonstrated that the designed two-different-size hole-arrayed index-guiding
SPCFs has a ultra-flattened chromatic dispersion of 0 ± 0.9 ps/(nm·km) in a wavelength range of 1.34 to 1.61 μm and low confinement
loss of less than 10−7 dB/m in a wavelength range of 1.2 to 1.7 μm. It has also been shown that the proposed SPCFs show reasonable dispersion tolerance. 相似文献
77.
Chilling resistances of isolates of Pythium ultimum var. ultimum from the Arctic and Temperate Zones
Hoshino T Tojo M Kanda H Herrero ML Tronsmo AM Kiriaki M Yokota Y Yumoto I 《Cryo letters》2002,23(3):151-156
Chilling resistances in moss pathogenic fungi, Pythium ultimum var. ultimum, from Longyearbyen, Svalbard (78 degree N, 15 degree E), located in the Arctic Zone and in the same isolates from Temperate Zone, were determined. Both strains had similar optimum growth temperatures. However, the strains from Svalbard could grow and survive at 0 - 5 degrees C. In addition, chilling treatment induced irregular mycelial morphology in the Arctic isolates. On the other hand, the isolates from Japan did not grow at temperatures below 5C and were destroyed after chilling stress (0 degree C for 3 days or at 4 degrees C for 1 week). The results suggested that isolates from Svalbard highly adapted to the severe spring condition in Polar environments. 相似文献
78.
Optical solitary waves that propagate in a Kerr medium exhibiting a power-law nonlocal response are studied analytically. The first-principles stability analysis based on quantum field theory shows that within the whole range of the exponent (the fractal dimension) the solitary wave can be stabilized. 相似文献
79.
We have determined the location of the miscibility gap in liquid Bi-BiBr3 system in the concentration-temperature, x?T, plane from the measurement of the electrical conductivity. The measurements have been done in the concentration range between 30.5 and 92.5 mol.% Bi and in the temperature range between 300 and 600°C. It is found that the temperature dependence of the conductivity of the mixture changes near the retrograde solubility region. 相似文献
80.
Takashi Okazaki Seiji Ōkubo Yūichi Hoshino Kanji Fujii 《Physics letters. [Part B]》1979,85(1):107-110
The validity of the assumption that decays into mesons proceed via ω, φ and ?0 poles followed by cascade decays is examined. is well reproduced by using and the B → ωπ helicity structure. The structure of OZI-violating transitions including the electromagnetic contribution is examined, and compared with the data on inclusive decay. 相似文献