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Mitsuhiro Wada Chieko Morinaka Toshihiko Ikenaga Naotaka Kuroda Kenichiro Nakashima 《Analytical sciences》2002,18(6):631-634
An HPLC method with fluorescence detection for the determination of nitric oxide (NO) in cultivated plant cells (Agave pacifica, Agavaceae) was developed. NO was derivatized in situ with 2,3-diaminonaphthalene (DAN) as a labeling reagent and converted to 1(H)-naphthotriazole. The maximum peak height of the derivative was observed by incubation for 3 h at 25 degrees C with 0.2 mM DAN. Excess reagent in cells was removed by washing 3 times with 5 ml of water. The calibration curve for authentic standard of DAN-NO spiked to cultivated plant cells showed a good linearity (r = 0.995) in the range of 5.0 to 50 pmol/g cell. The detection limit at a signal-to-noise ratio of 3 was 3.4 pmol/g cells. The proposed method was successfully applied to the monitoring of NO concentration with cell growth. The effect of thermal treatment on the concentration of NO in plant cells was also examined. The concentration of NO in cells treated at 5 degrees C for 1 h was significantly higher than that treated at 25 degrees C and 35 degrees C for 1 h (n = 3, p < 0.05). 相似文献
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Masaki Kashiwara Toshiki Nakashima Masato Okado 《Transactions of the American Mathematical Society》2008,360(7):3645-3686
For every non-exceptional affine Lie algebra, we explicitly construct a positive geometric crystal associated with a fundamental representation. We also show that its ultra-discretization is isomorphic to the limit of certain perfect crystals of the Langlands dual affine Lie algebra.
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Bishnu Prasad Bastakoti Sudhina Guragain Yuuichi Yokoyama Shin-ichi Yusa Kenichi Nakashima 《Colloid and polymer science》2010,288(9):991-996
Organic–inorganic nanohybrid particles are prepared in aqueous solution from poly(ethylene oxide-b-sodium 2-acrylamido-1-propanesulfonate-b-styrene) (PEO-b-PAMPS-b-PS) triblock copolymer and ferric ions. The hybrid micelles were characterized by dynamic light scattering, scanning electron
microscopy, transmission electron microscopy, and zeta-potential measurements. The hydrodynamic diameter of the hybrid micelles
ranges from 68 to 118 nm depending on the concentration of the polymer and the amount of ferric ions loaded on the polymer.
Zeta-potential measurements revealed that the micelles are assembled mainly by electrostatic interaction between the ferric
ions and the negatively charged PAMPS block in the PEO-b-PAMPS-b-PS. 相似文献
58.
Asako Shimada Tomoko Haraga Akiko Hoshi Yutaka Kameo Mikio Nakashima Kuniaki Takahashi 《Journal of Radioanalytical and Nuclear Chemistry》2010,286(3):765-770
In order to analyze actinide elements in radioactive metal waste, the dissolution and chemical separation conditions were optimized. The surfaces of a type 304 stainless steel plate and of pipe waste sampled from the prototype advanced thermal reactor (Fugen) were dissolved in mixed acid solution (HNO3:HCl:H2O = 1:1:4). The resulting solution was evaporated to dryness and dissolved with 2 mol/dm3 of HNO3 to prepare sample solutions. In order to analyze trivalent actinide elements in the sample solution containing a large amount of Fe(III) (>0.1 g) using TRU resin, the effect of Fe(III) concentration on the recovery of Am(III) and reduction effect of Fe(III) to Fe(II) with ascorbic acid were studied. On the basis of results of this study, chemical separation scheme was constructed and Pu and Am in the sample solutions were separated. Thorium and U in the sample solutions were separated with UTEVA resin. High recoveries for all experimented elements were obtained from the analysis of spiked sample solutions, the effectiveness of the method was confirmed. 相似文献
59.
Microwave-assisted synthesis method enabled the preparation of the (tris-acetylacetonate)(2,9-dimethyl-4,7-diphenyl-1,10-phenanthrolinate) terbium(III) (Tb(acac)3(dmdpphen)) complex with outstanding high green luminescence. This method is appropriate for green chemistry and energy-saving processes. The Tb(acac)3(dmdpphen) complex has good thermal stability. Emission peaks are assigned to the f-f transitions of the Tb3+. The Tb(acac)3(dmdpphen) complex is expected to be used in functional materials of electronic products. 相似文献
60.
Amal Kaddoumi Mitsuhiro Wada Kenichiro Nakashima 《Biomedical chromatography : BMC》2011,25(5):579-587
N‐Nitrosofenfluramine (N‐Fen), a synthetic adulterant in Chinese herbal diet products, is believed to cause hepatotoxicity in people who use these products. N‐Fen is a relatively new compound, and thus pharmacological and toxicological studies are insufficient. The aim of this work was to (1) define N‐Fen's plasma pharmacokinetics and tissue distribution after single intraperitoneal (i.p.) administration of 25 mg/kg to rats; (2) define its bioavailability; and (3) identify fenfluramine (Fen) and norfenfluramine (Norf) as N‐Fen metabolites. N‐Fen rapidly appeared in the circulation and was distributed to all tissues. Norf was found to be the primary metabolite and not Fen. Plasma and tissue levels of N‐Fen and Norf were low with bioavailability of N‐Fen after i.p. administration was <3%. The AUC0−t of N‐Fen in the liver and kidney were 6.6 and 12.1 times, respectively, greater than the brain, and 17.8 and 32.6 times, respectively, greater than the plasma. In conclusion, N‐Fen did not show local accumulation in the liver, the site of toxicity, with concentrations represented as percentage of the total dose ranginng from 0.008 to 0.122%; hence the cause of hepatotoxicity could be related to the mechanisms other than toxicity consequences accumulation. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献