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101.
Yae Eun Chong Manting Chiang Kiran Deshpande Simon Haroutounian Leonid Kagan Jong Bong Lee 《Biomedical chromatography : BMC》2019,33(11)
Ondansetron, a widely used antiemetic agent, is a P‐glycoprotein (P‐gp) substrate and therefore expression of P‐gp at the blood–brain barrier limits its distribution to the central nervous system (CNS), which was observed to be reversed by coadministration with P‐gp inhibitors. Tariquidar is a potent and selective third‐generation P‐gp inhibitor, and coadministration with ondansetron has shown improved ondansetron distribution to the CNS. There is currently no reported bioanalytical method for simultaneously quantifying ondansetron with a third‐generation P‐gp inhibitor. Therefore, we aimed to develop and validate a method for ondansetron and tariquidar in rat and human plasma samples. A full validation was performed for both ondansetron and tariquidar, and sample stability was tested under various storage conditions. To demonstrate its utility, the method was applied to a preclinical pharmacokinetic study following coadministration of ondansetron and tariquidar in rats. The presented method will be valuable in pharmacokinetic studies of ondansetron and tariquidar in which simultaneous determination may be required. In addition, this is the first report of a bioanalytical method validated for quantification of tariquidar in plasma samples. 相似文献
102.
Development of simultaneous analysis of tryptophan metabolites in serum and gastric juice – an investigation towards establishing a biomarker test for gastric cancer diagnosis 下载免费PDF全文
Jong Min Choi Won Sang Park Kyo Young Song Hwa Jeong Lee Byung Hwa Jung 《Biomedical chromatography : BMC》2016,30(12):1963-1974
To evaluate changes in tryptophan metabolism and discover diagnostic biomarkers for gastric cancer, a quantitative method was developed for tryptophan and its seven metabolites (indole‐3‐lactic acid, anthranilic acid, serotonin, nicotinic acid, kynurenic acid, kynurenine and 3‐indoxyl sulfate) in both human serum and gastric juice using liquid chromatography–tandem mass spectrometry (LC–MS/MS). Serum and gastric juice were prepared with a simple protein precipitation using aqueous 0.1% formic acid and acetonitrile. As a result, it was found that the kynurenine pathway of tryptophan metabolism was activated in gastric cancer and that the metabolic ratio of kynurenine/tryptophan, which reflects the enzyme activity of indoleamine‐2,3‐dioxygenase, was associated with the observed metabolic changes. Finally, the investigation of tryptophan metabolites, especially kynurenic acid, in serum and gastric juice might serve as biomarkers for gastric cancer. The findings in this study provide critical information of tryptophan metabolism which can be applied to a serum‐based diagnostic test for gastric cancer. 相似文献
103.
Journal of Radioanalytical and Nuclear Chemistry - As a result of nuclear power plant accidents such as Chernobyl and Fukushima, and even their maintenance, the soil is contaminated due to the... 相似文献
104.
Carbon supports modified with well dispersed anatase TiO2 (C–Ti-X; X (0.25, 0.5, 0.75, and 1.0) represents mass ratio of Ti precursor to carbon) were synthesized with various Ti loadings and used to support Pd catalysts for oxygen reduction. The anatase nanoparticles increased in size with increasing Ti loading. Pd dispersion improved with increasing Ti loading up to the C–Ti-0.75, which resulted in the best catalytic activity. Although the Pd dispersion was lowest on the C–Ti-1.0, it showed better catalytic performance than the catalysts supported on C–Ti-0.25 and C–Ti-0.5. At 0.8 V (vs. RHE), the best catalytic activity achieved was respectively 2.7 and 2.7 times the mass and specific activities of Pd supported on un-modified carbon. The interaction between Pd and highly dispersed TiO2 is believed to improve the catalytic activity of Pd supported on TiO2-modified carbons. 相似文献
105.
Hendrik P. Benschop C. A. G. Konings L. P.A. De Jong H. Kienhuis J. Van Genderen 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-3):345-349
Abstract The four stereoisomers of pinacolyl methylphospho-nofluoridate (soman) were isolated with more than 99% optical purity. The bimolecular rate constants for inhibition of electric eel acetylcholinesterase and the LD50-values (sc, mice) of the stereoisomers were determined. 相似文献
106.
Richard A. Bartsch Takashi Hayashita Joung Hae Lee Jong Seung Kim Matthew G. Hankins 《Supramolecular chemistry》2013,25(3-4):305-311
Abstract Lipophilic crown ethers with pendent proton-ionizable groups are novel complexing agents for use in metal ion separations by solvent extraction. For a series of structurally related, lipophilic dibenzocrown ether carboxylic acids, the efficiency and selectivity of competitive alkali metal cation extraction for aqueous solution into chloroform is found to be strongly influenced by the crown ether ring size and the lipophilic group attachment site. Reaction of dibenzocrown ether carboxylic acids with formaldehyde in formic acid produces condensation polymers which possess both ion-exchange and cyclic polyether binding sites for metal ion complexation. These resins exhibit excellent exchange kinetics for competitive alkali metal cation sorption from aqueous solution and subsequent stripping and may be used in concentrator columns for the recovery of these metal ions from very dilute aqueous solution. Cation selectivity in the sorption and stripping steps is controlled by the structure of the crown ether monomer unit. 相似文献
107.
108.
Sunwoong Bae Chul Woong Kim Jong Seob Choi Ji-Won Yang Tae Seok Seo 《Analytical and bioanalytical chemistry》2013,405(29):9365-9374
This study describes the development of a microfluidic device for the high-throughput screening of culture conditions, such as the optimum sodium acetate concentration for promoting rapid growth and high lipid accumulation of Chlamydomonas reinhardtii. An analysis of the microalgal growth on the microfluidic device revealed an optimum sodium acetate concentration of 5.72 g L?1. The lipid content, determined by the 4,4-Difluoro-1,3,5,7-tetramethyl-4-bora-3a,4a-diaza-s-indacene (BODIPY® 505/515) staining method, increased with the sodium acetate concentration. The results were found to be statistically reproducible with respect to cell growth and lipid production. Other nutrient conditions, including the nitrogen and phosphorus concentrations, can also be optimized on the same microfluidic platform. The microfluidic device performance results agreed well with the results obtained from the flask-scale experiments, validating that the culture conditions were scalable. Finally, we, for the first time, established a method for the absolute quantification of the microalgal lipid content in the picoliter culture volumes by comparing the on-chip and off-chip data. In conclusion, we successfully demonstrated the high-throughput screening of sodium acetate concentrations that induced high growth rates and high lipid contents in C. reinhardtii cells on the microfluidic device. Figure
We have developed a microfluidic device for the high-throughput screening of culture conditions for promoting rapid growth and high lipid accumulation of Chlamydomonas reinhardtii 相似文献
109.
1,3-diproyloxycalix[4]arene azacrown ether was successfully synthesized in the fixed 1,3-alternate conformation which was confirmed by a solid state structure. 相似文献
110.