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| 1.
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Hayakawa, Kazuichi ; Miyoshi, Yasuko ; Kurimoto, Hiroaki ; Matzushima, Yuko ; Takayama, Nariaki ; Tanaka, Seishi ; Miyazaki, Motoichi ; 早川, 和一 ; 三好, 裕子 ; 栗本, 博昭 ; 松島, 優子 ; 高山, 成明 ; 田中, 星司 ; 宮崎, 元一
概要:
金沢大学理工研究域自然システム学系<br />A HPLC determination method for methamphetamine (MA) and its metabolites in the urine samples of
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abusers has been developed. MA, amphetamine (AP), norephedrine (NE), p-hydroxymethamphetamine (pOHMA), p-hydoroxyamphetamine (pOHAP) and an internal standard, namely β-phenylethylamine (PEA) were derivatized with dansyl chloride. They were separated on a reversed phase column with gradient elution using an acetonitrile/tetrahydrofuran/imidazole buffer mobile phase and chemilumigenically determined using bis(2, 4, 6-trichlorophenyl)-oxalate/hydrogen peroxide as post column reagents. The lower determination limits were as low as 1×10-14-3×10-14mol. AP, NE, pOHAP and PEA were derivatized with naphthalene-2, 3-dicarboxaldehyde, and were separated on a reversed phase column using an acetonitrile/imidazole buffer mobile phase and chemilumigenically determined. The lower determination limits were 3×10-16-1.5×10-15mol. Enzymatic hydrolysis of glucuronides of pOHMA (pOHMAG) and pOHAP (pOHAPG) allowed them to be determined as pOHMA and pOHAP, respectively. After adjusting the pH of the urine samples to 10.5 and adding PEA, all metabolites except glucuronides were extracted quantitatively into chloroform-isopropanol (3 : 1). Utilizing the two methods, MA and all metabolites were determined in urine samples of MA abusers. The tendency, in order of decreasing concentration was : [MA]>[A]>[pOHMAG]>[pOHMA]>[NE]>[pOHAPG]>[pOHAP]. Although ephedrine (EP) was detected in several samples, it was not considered to be a metabolite of MA but rather a component derived from cough medicine.
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| 2.
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Bekki, Kanae ; Toriba, Akira ; Ning, Tang ; Kameda, Takayuki ; Hayakawa, Kazuichi ; 戸次, 加奈江 ; 鳥羽, 陽 ; 唐, 寧 ; 亀田, 貴之 ; 早川, 和一
概要:
金沢大学理工研究域自然システム学系<br />Polycyclic aromatic hydrocarbons (PAHs) are included in various environmental pollutants such as
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airborne particles and have been reported to induce a variety of toxic effects. On the other hand, PAH derivatives are generated from PAHs both through chemical reaction in the atmosphere and metabolism in the body.PAH derivatives have become known for their specific toxicities such as estrogenic/antiestrogenic activities and oxidative stress, and correlations between the toxicities and structures of PAH derivatives have been shown in recent studies. These studies are indispensable for demonstrating the health effects of PAH derivatives, since they would contribute to the comprehensive toxicity prediction of many kinds of PAH derivatives.<br />多環芳香族炭化水素類（PAHs）は大気粉塵などの多種類の環境汚染物質に含まれ，長年の研究によって多様な生体影響を引き起こすことが知られている．一方で，PAHsは生体内での代謝反応や，大気中での化学反応によって多種多様な誘導体を生成することが知られている．近年では，PAHだけでなくPAH誘導体の毒性影響が着目されており，エストロゲン様/抗エストロゲン作用，酸化ストレス反応など，PAHとは異なる誘導体独自の毒性影響の存在が報告されている．また，生成するPAH誘導体には多くの構造異性体が存在するが，PAH誘導体が示す毒性作用と構造との間に相関性，いわゆる構造活性相関があることが示されている．以上の研究は，環境中に存在するPAH 誘導体の生体影響を解明する上で重要な研究であるとともに，多種多様なPAH誘導体の総合的な毒性影響予測に貢献できると考えられる．
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| 3.
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Higashi, Tomomi ; Ohkura, Noriyuki ; Fujimura, Masaki ; Nakai, Satoshi ; Honda, Yasushi ; Saijoh, Kiyofumi ; Hayakawa, Kazuichi ; Kobayashi, Fumihisa ; Michigami, Yoshimasa ; Olando, Anyenda Enoch ; Hitomi, Yoshiaki ; Nakamura, Hiroyuki ; 東, 朋美 ; 大倉, 徳幸 ; 藤村, 政樹 ; 西條, 淸史 ; 早川, 和一 ; 小林, 史彦 ; 道上, 義正 ; 人見, 嘉哲 ; 中村, 裕之
概要:
金沢大学医薬保健研究域医学系<br />Asian dust, known as kosa in Japanese, is a major public health concern. In this panel study, we eva
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luated the effects of exposure to kosa on daily cough occurrence. The study subjects were 86 patients being treated for asthma, cough variant asthma, or atopic cough in Kanazawa University Hospital from January 2011 to June 2011. Daily mean concentrations of kosa and spherical particles were obtained from light detection and ranging (LIDAR) measurements, and were categorized from Grade 1 (0 μg/m3) to 5 (over 100 μg/m3). The association between kosa and cough was analyzed by logistic regression with a generalized estimating equation. Kosa effects on cough were seen for all Grades with potential time lag effect. Particularly at Lag 0 (the day of exposure), a dose-response relationship was observed: the odds ratios for Grades 2, 3, 4, and 5 above the referent (Grade 1) were 1.111 (95% confidence interval (CI): 0.995-1.239), 1.171 (95% CI: 1.006-1.363), 1.357 (95% CI: 1.029-1.788), and 1.414 (95% CI: 0.983-2.036), respectively. Among the patients without asthma, the association was higher: the odds ratios for Grades 2, 3, 4 and 5 were 1.223 (95% CI: 0.999-1.497), 1.309 (95% CI: 0.987-1.737), 1.738 (95% CI: 1.029-2.935) and 2.403 (95% CI: 1.158-4.985), respectively. These associations remained after adjusting for the concentration of spherical particles or particulate matter with an aerodynamic diameter of less than 2.5 μm (PM2.5). Our findings demonstrate that kosa is an environmental factor which induces cough in a dose-response relationship. © 2014 Elsevier B.V.<br />Embargo Period 12 months
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| 4.
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Kakimoto, Kensaku ; Toriba, Akira ; Ohno, Takanori ; Ueno, Mariko ; Kameda, Takayuki ; Tang, Ning ; Hayakawa, Kazuichi
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金沢大学医薬保健研究域薬学系<br />To evaluate human exposure to polycyclic aromatic hydrocarbons (PAHs), we developed a rapid, simple
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and sensitive method for determining 1-hydroxypyrene-glucuronide (1-OHP-G) in human urine. To improve precision, a deuterated glucuronide was used as an internal standard. The method requires only 1 mL of urine. The urine was treated with a mixed-mode anion-exchange and reversed-phase solid-phase extraction cartridge (Oasis MAX). The analytes were analyzed with a C18 reversed-phase column with a gradient elution, followed by tandem mass spectrometry with electrospray ionization in negative ion mode. The detection limit of 1-OHP-G (corresponding to a signal-to-noise ratio of 3) was 0.13 fmol/injection. Urinary concentrations of 1-OHP-G determined by this method were strongly correlated (r2 = 0.961) with concentrations of 1-hydroxypyrene by conventional HPLC with fluorescence detection. © 2008 Elsevier B.V. All rights reserved.
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| 5.
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Akutsu, Kazuhiko ; Takatori, S. ; Nozawa, S. ; Yoshiike, M. ; Nakazawa, H. ; Hayakawa, Kazuichi ; Makino, T. ; Iwamoto, T.
概要:
Polybrominated diphenyl ethers (PBDEs) are widely used flame retardants; currently, they are identified as ubiquitous en
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vironmental contaminants. Several studies indicate that PBDEs might affect male fertility. We present the results of a pilot study on the relationship between human serum PBDEs and sperm quality. The PBDE levels in Japan are comparable to those found in European countries. Strong inverse correlations were observed between the serum concentration of 2,2′,4,4′,5,5′-hexabromodiphenyl ether and sperm concentration (r = -0.841, p = 0.002) and testis size (r = -0.764, p = 0.01). Extensive studies on the relationship between PBDEs and sperm quality are required. © 2008 Springer Science+Business Media, LLC.
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| 6.
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Hosozumi, Chiemi ; Toriba, Akira ; Chuesaard, Thanyarat ; Kameda, Takayuki ; Tang, Ning ; Hayakawa, Kazuichi
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Urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) is a widely used noninvasive biomarker of oxidative stress. A selective, se
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nsitive and rapid method for determining 8-OHdG in human urine was developed using hydrophilic interaction chromatography-tandem mass spectrometry (HILIC-MS/MS) with electrospray ionization. 8-OHdG and isotopically labeled 8-OHdG (internal standard) were separated on a HILIC column with a mobile phase of 10. mM ammonium acetate: acetonitrile (1:9, v/v) within 10. min and detected by using a positive electrospray ionization interface under the selected reaction monitoring mode. The detection limits of 8-OHdG (corresponding to a signal-to-noise ratio of 3) for the HILIC-MS/MS system and the conventional method using a reversed-phase column with MS/MS were 1.0 and 26.0. fmol/injection, respectively. The proposed method makes it possible to monitor the basal level of urinary 8-OHdG from non-exposed healthy subjects and can be used for large-scale human studies. © 2012 Elsevier B.V.
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| 7.
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Tang, Ning ; Tokuda, Takahiro ; Izzaki, Akihiko ; Tamura, Kenji ; Ji, Ruonan ; Zhang, Xuemei ; Dong, Lijun ; Kameda, Takayuki ; Toriba, Akira ; Hayakawa, Kazuichi
概要:
Airborne particulates were collected in three size fractions by using Anderson low-volume air samplers in Shenyang, Chin
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a, in winter and summer in 2007. Compared with data obtained in 2001 at the same sites, the total concentrations of nine polycyclic aromatic hydrocarbons (PAHs) in winter decreased by 67% at one site and decreased by 40% at the other site, while the total concentrations of four nitropolycyclic aromatic hydrocarbons (NPAHs) did not decrease. This suggests that environmental countermeasures begun in 2001 were effective in decreasing the concentration of PAHs. However, in summer, the concentrations of PAHs and NPAHs rose by the factors of 4 and 5, respectively, possibly because of an increase in the number of motor vehicles. © 2011 Taylor and Francis Group, LLC.
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| 8.
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Sugitate, Kuniyo ; Yamagami, Takashi ; Nakamura, Sadao ; Toriba, Akira ; Hayakawa, Kazuichi
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Fenthion, fenthion sulfoxide, fenthion oxon sulfoxide and fensulfothion showed two different mass spectra in GC/MS, depe
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nding on their concentrations. The base peaks shifted to lower levels by 1 m/z at lower concentration, and no retention time shifts were observed. The "shifted base peaks" were not obtained by a general EI fragmentation. The product ion scan spectra of the "shifted base peaks" were coincident with those of molecular ions of their corresponding sulfides. These phenomena can be ascribed to the conversion of sulfoxide into sulfide by the dominant deoxidation reaction than EI fragmentation in an ion source. Adding polyethylene glycol 300 (PEG300) into a test solution prevented sulfoxide deoxidation. © The Japan Society for Analytical Chemistry.
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| 9.
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Koyama, Kazuo ; Hirao, Takashi ; Toriba, Akira ; Hayakawa, Kazuichi
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The quality of starch-containing foods may be significantly impaired by contamination with very small amounts of α-amyla
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se, which can enzymatically hydrolyze the starch and cause viscosity loss. Thus, for quality control, it is necessary to have an analytical method that can measure low amylase activity. We developed a sensitive analytical method for measuring the activity of α-amylase (from Bacillus subtilis) in starch-containing foods. The method consists of six steps: (1) crude extraction of α-amylase by centrifugation and filtration; (2) α-amylase purification by desalting and anion-exchange chromatography; (3) reaction of the purified amylase with boron-dipyrromethene (BODIPY)-labeled substrate, which releases a fluorescent fragment upon digestion of the substrate, thus avoiding interference from starch derivatives in the sample; (4) stopping the reaction with acetonitrile; (5) reversed-phase solid-phase extraction of the fluorescent substrate to remove contaminating dye and impurities; and (6) separation and measurement of BODIPY fluorescence by HPLC. The proposed method could quantify α-amylase activities as low as 10mU/mL, which is enough to reduce the viscosity of starch-containing foods. © 2012 John Wiley & Sons, Ltd.
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| 10.
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10. Characterization and functionality of immidazolium ionic liquids modified magnetic nanoparticles
Li, Ying ; Tang, Ning ; Inagaki, Fuyuhiko ; Mukai, Chisato ; Hayakawa, Kazuichi
概要:
1,3-Dialkylimidazolium-based ionic liquids were chemically synthesized and bonded on the surface of magnetic nanoparticl
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es (MNPs) with easy one-step reaction. The obtained six kinds of ionic liquid modified MNPs were characterized with transmission electron microscopy, thermogravimetric analysis, magnetization, and FTIR, which owned the high adsorption capacity due to the nanometer size and high-density modification with ionic liquids. Functionality of MNPs with ionic liquids greatly influenced the solubility of the MNPs with organic solvents depending on the alkyl chain length and the anions of the ionic liquids. Moreover, the obtained MNPs showed the specific extraction efficiency to organic pollutant, polycyclic aromatic hydrocarbons, while superparamagnetic property of the MNPs facilitated the convenient separation of MNPs from the bulks water samples. © 2013 Ying Li et al.
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