Search Results - "YAMASHITA, Kouwa"

Proton Affinitive Derivatization for Highly Sensitive Determination of Testosterone and Dihydrotestosterone in Saliva Samples by LC-ESI-MS/MS by OHNO, Ken-ichi, HASEGAWA, Tomomi, TAMURA, Tomomi, UTSUMI, Haruka, YAMASHITA, Kouwa

“…In this study, proton affinitive derivatization using picolinic acid and its analogs (3- and 6-methylpicolinic acid and 5-butylpicolinic acid) with proton…”
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Highly sensitive quantification of key regulatory oxysterols in biological samples by LC-ESI-MS/MS by Honda, Akira, Yamashita, Kouwa, Hara, Takashi, Ikegami, Tadashi, Miyazaki, Teruo, Shirai, Mutsumi, Xu, Guorong, Numazawa, Mitsuteru, Matsuzaki, Yasushi

“…We describe a highly sensitive and specific method for the quantification of key regulatory oxysterols in biological samples. This method is based upon a…”
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Highly sensitive analysis of sterol profiles in human serum by LC-ESI-MS/MS by Honda, Akira, Yamashita, Kouwa, Miyazaki, Hiroshi, Shirai, Mutsumi, Ikegami, Tadashi, Xu, Guorong, Numazawa, Mitsuteru, Hara, Takashi, Matsuzaki, Yasushi

“…We have developed a highly sensitive and specific method for the analysis of serum sterol profiles. Sterols in 1 μl of dried serum were derivatized into…”
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Benzophenones from an Endophytic Fungus, Graphiopsis chlorocephala, from Paeonia lactiflora Cultivated in the Presence of an NAD+‑Dependent HDAC Inhibitor by Asai, Teigo, Otsuki, Sae, Sakurai, Hiroaki, Yamashita, Kouwa, Ozeki, Tomoji, Oshima, Yoshiteru

“…Graphiopsis chlorocephala was separated from the surface-sterilized healthy leaves of Paeonia lactiflora (Paeoniaceae) and cultivated with nicotinamide (an…”
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Dihydrobenzofurans as cannabinoid receptor ligands from Cordyceps annullata, an entomopathogenic fungus cultivated in the presence of an HDAC inhibitor by Asai, Teigo, Luo, Dan, Obara, Yutaro, Taniguchi, Tohru, Monde, Kenji, Yamashita, Kouwa, Oshima, Yoshiteru

“…The secondary metabolite production of Cordyceps annullata, an entomopathogenic fungus, was clearly enhanced by the addition of suberoyl bis-hydroxamic acid…”
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Analytical chemistry for ADMET research: Recent advances and future directions in LC–MS/MS and omics approaches by Yoshinari, Kouichi, Yamashita, Kouwa

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Development of highly sensitive quantification method for testosterone and dihydrotestosterone in human serum and prostate tissue by liquid chromatography–electrospray ionization tandem mass spectrometry by Yamashita, Kouwa, Miyashiro, Yoshimichi, Maekubo, Hitoe, Okuyama, Mitsunobu, Honma, Seijiro, Takahashi, Madoka, Numazawa, Mitsuteru

“…We developed highly sensitive detection of testosterone (T) and 5α-dihydrotestosterone (DHT) by liquid chromatography–electrospray ionization tandem mass…”
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18-Oxocortisol Measurement in Adrenal Vein Sampling as a Biomarker for Subclassifying Primary Aldosteronism by Nakamura, Yasuhiro, Satoh, Fumitoshi, Morimoto, Ryo, Kudo, Masataka, Takase, Kei, Gomez-Sanchez, Celso E, Honma, Seijiro, Okuyama, Mitsunobu, Yamashita, Kouwa, Rainey, William E, Sasano, Hironobu, Ito, Sadayoshi

“…Context: 18-Oxocortisol (18-oxoF) is a derivative of cortisol (F) that is produced by aldosterone synthase (CYP11B2). The potential for this steroid as a…”
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Highly sensitive determination of estrone and estradiol in human serum by liquid chromatography–electrospray ionization tandem mass spectrometry by Yamashita, Kouwa, Okuyama, Mitsunobu, Watanabe, Yoko, Honma, Seijiro, Kobayashi, Sayuri, Numazawa, Mitsuteru

“…A highly sensitive and specific quantification method of estrone and estradiol in human serum was described based upon the use of picolinoyl derivatization and…”
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Highly sensitive and specific analysis of sterol profiles in biological samples by HPLC–ESI–MS/MS by Honda, Akira, Miyazaki, Teruo, Ikegami, Tadashi, Iwamoto, Junichi, Yamashita, Kouwa, Numazawa, Mitsuteru, Matsuzaki, Yasushi

“…High-performance liquid chromatography–tandem mass spectrometry (HPLC–MS/MS) is a powerful method for the microanalysis of compounds in biological samples…”
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Use of novel picolinoyl derivatization for simultaneous quantification of six corticosteroids by liquid chromatography-electrospray ionization tandem mass spectrometry by Yamashita, Kouwa, Takahashi, Madoka, Tsukamoto, Satoshi, Numazawa, Mitsuteru, Okuyama, Mitsunobu, Honma, Seijiro

“…Simultaneous quantification method of six corticosteroids, cortisone, cortisol, cortexolone, corticosterone, dehydrocorticosterone and deoxycorticosterone, by…”
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Synthesis of pyridine-carboxylate derivatives of hydroxysteroids for liquid chromatography–electrospray ionization-mass spectrometry by Yamashita, Kouwa, Kobayashi, Sayuri, Tsukamoto, Satoshi, Numazawa, Mitsuteru

“…Synthesis and liquid chromatography-electrospray ionization-mass spectrometric (LC–ESI-MS) behaviors of the picolinoyl, 6-methylpicolinoyl, nicotinoyl,…”
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Highly oxidized ergosterols and isariotin analogs from an entomopathogenic fungus, Gibellula formosana, cultivated in the presence of epigenetic modifying agents by Asai, Teigo, Chung, Yu-Ming, Sakurai, Hiroaki, Ozeki, Tomoji, Chang, Fang-Rong, Wu, Yang-Chang, Yamashita, Kouwa, Oshima, Yoshiteru

“…The concomitant addition of a histone deacetylase inhibitor, suberoyl bis-hydroxamic acid, and a DNA methyltransferase inhibitor, RG-108, to the culture medium…”
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Highly sensitive quantification of 7α-hydroxy-4-cholesten-3-one in human serum by LC-ESI-MS/MS by Honda, Akira, Yamashita, Kouwa, Numazawa, Mitsuteru, Ikegami, Tadashi, Doy, Mikio, Matsuzaki, Yasushi, Miyazaki, Hiroshi

“…We describe a highly sensitive and specific method for the quantification of serum 7α-hydroxy-4-cholesten-3-one (C4), which has been used as a biomarker for…”
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Simultaneous quantification of salivary 3-hydroxybutyrate, 3-hydroxyisobutyrate, 3-hydroxy-3-methylbutyrate, and 2-hydroxybutyrate as possible markers of amino acid and fatty acid catabolic pathways by LC–ESI–MS/MS by Miyazaki, Teruo, Honda, Akira, Ikegami, Tadashi, Iwamoto, Junichi, Monma, Tadakuni, Hirayama, Takeshi, Saito, Yoshifumi, Yamashita, Kouwa, Matsuzaki, Yasushi

“…We have developed a highly sensitive and specific method for quantification of salivary 3-hydroxybutyrate (3HB), 3-hydroxyisobutyrate (3HIB),…”
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Aromatic polyketide glycosides from an entomopathogenic fungus, Cordyceps indigotica by Asai, Teigo, Yamamoto, Takashi, Chung, Yu-Ming, Chang, Fang-Rong, Wu, Yang-Chang, Yamashita, Kouwa, Oshima, Yoshiteru

“…A new aromatic polyketide glycoside, indigotide A ( 1), was isolated from the culture broth of the entomopathogenic fungus, Cordyceps indigotica, along with…”
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Fusaric Acid as a Novel Proton-Affinitive Derivatizing Reagent for Highly Sensitive Quantification of Hydroxysteroids by LC-ESI-MS/MS by Yamashita, Kouwa, Yamazaki, Keiko, Komatsu, Sachiko, Numazawa, Mitsuteru

“…A highly sensitive derivatization method for liquid chromatography (LC)-electrospray ionization (ESI) tandem mass spectrometry of dehydroepiandrosterone…”
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An Innovative LC-MS/MS-Based Method for Determining CYP 17 and CYP 19 Activity in the Adipose Tissue of Pre- and Postmenopausal and Ovariectomized Women Using 13C-Labeled Steroid Substrates by Kinoshita, Toshihiko, Honma, Seijiro, Shibata, Yasuhiro, Yamashita, Kouwa, Watanabe, Yoko, Maekubo, Hitoe, Okuyama, Mitsunobu, Takashima, Akiko, Takeshita, Naoki

“…Context: Does adipose tissue produce steroid hormones like an endocrine organ? Object: To clarify whether adipose tissue produces sex steroid hormone like an…”
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Simultaneous determination of tetrahydrocortisol, allotetrahydrocortisol and tetrahydrocortisone in human urine by liquid chromatography-electrospray ionization tandem mass spectrometry by Yamashita, Kouwa, Nakagawa, Risa, Okuyama, Mitsunobu, Honma, Seijiro, Takahashi, Madoka, Numazawa, Mitsuteru

“…Simultaneous quantification method of three major metabolites of cortisone and cortisol, tetrahydrocortisol, allotetrahydrocortisol and tetrahydrocortisone by…”
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Structures and absolute configurations of short-branched fatty acid dimers from an endophytic fungus of Aloe arborescens by Asai, Teigo, Otsuki, Sae, Taniguchi, Tohru, Monde, Kenji, Yamashita, Kouwa, Sakurai, Hiroaki, Ozeki, Tomoji, Oshima, Yoshiteru

“…Mycosphines A–D (1–4), comprising a class of new short-branched fatty acid dimers, were found in the cultures of an endophytic fungus, Mycosphaerella sp.,…”
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