Kazuichi Hayakawa

Kanazawa University, Kanazawa, Ishikawa, Japan

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Publications (308)589.15 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: We previously demonstrated that monohydroxylated polycyclic aromatic hydrocarbons (OHPAHs), which are metabolites of polycyclic aromatic hydrocarbons (PAHs), act on calcified tissue and suppress osteoblastic and osteoclastic activity in the scales of teleost fish. The compounds may possibly influence other calcified tissues. Thus, the present study noted the calcified spicules in sea urchins and examined the effect of both PAHs and OHPAHs on spicule formation during the embryogenesis of sea urchins. After fertilization, benz[a]anthracene (BaA) and 4-hydroxybenz[a]anthracene (4-OHBaA) were added to seawater at concentrations of 10(-8) and 10(-7)M and kept at 18°C. The influence of the compound was given at the time of the pluteus larva. At this stage, the length of the spicule was significantly suppressed by 4-OHBaA (10(-8) and 10(-7)M). BaA (10(-7)M) decreased the length of the spicule significantly, while the length did not change with BaA (10(-8)M). The expression of mRNAs (spicule matrix protein and transcription factors) in the 4-OHBaA (10(-7)M)-treated embryos was more strongly inhibited than were those in the BaA (10(-7)M)-treated embryos. This is the first study to demonstrate that OHPAHs suppress spicule formation in sea urchins. Copyright © 2015. Published by Elsevier Inc.
    Comparative Biochemistry and Physiology Part C Toxicology & Pharmacology 02/2015; 171. DOI:10.1016/j.cbpc.2015.02.004 · 2.83 Impact Factor
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    ABSTRACT: Three compounds, hypothesized as fumonisin A1 (FA1), fumonisin A2 (FA2), and fumonisin A3 (FA3), were detected in a corn sample contaminated with mycotoxins by high-resolution liquid chromatography-Orbitrap mass spectrometry (LC-Orbitrap MS). One of them has been identified as FA1 synthesized by the acetylation of fumonisin B1 (FB1), and established a method for its quantification. Herein, we identified the two remaining compounds as FA2 and FA3, which were acetylated fumonisin B2 (FB2) and fumonisin B3 (FB3), respectively. Moreover, we examined a method for the simultaneous analysis of FA1, FA2, FA3, FB1, FB2, and FB3. The corn samples were prepared by extraction using a QuEChERS kit and purification using a multifunctional cartridge. The linearity, recovery, repeatability, limit of detection, and limit of quantification of the method were >0.99, 82.9%-104.6%, 3.7%-9.5%, 0.02-0.60 μg/kg, and 0.05-1.98 μg/kg, respectively. The simultaneous analysis of the six fumonisins revealed that FA1, FA2, and FA3 were present in all corn samples contaminated with FB1, FB2, and FB3. The results suggested that corn marketed for consumption can be considered as being contaminated with both the fumonisin B-series and with fumonisin A-series. This report presents the first identification and quantification of FA1, FA2, and FA3 in corn samples.
    Toxins 02/2015; 7(2):582-92. DOI:10.3390/toxins7020582 · 2.48 Impact Factor
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  • Chau Thuy Pham, Ning Tang, Akira Toriba, Kazuichi Hayakawa
    Polycyclic Aromatic Compounds 01/2015; DOI:10.1080/10406638.2014.903284 · 0.83 Impact Factor
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    ABSTRACT: Polycyclic aromatic hydrocarbons (PAHs) are known as carcinogenic and/or mutagenic substances, and are present at high concentration in polluted environments. It has recently been reported that spore-forming bacteria (e.g., Bacillus spp.) can be transported long distances alive in the atmosphere, which raises the possibility that some of the transported bacteria could have adverse effects on human health. There is thus a need for filters that can remove gaseous PAHs from the air that people breathe and that can inhibit bacterial growth on the filters. We focused on metallophthalocyanine derivatives (M-Pc) which are known to adsorb PAHs as well as to inhibit the growth of bacteria as a potential filtering agent. In this study, we developed different types of M-Pc-supported rayon fibers by changing central metals, functional groups, concentrations of M-Pc and rayon types, and evaluated their removal effects by measuring adsorption rates of 3- and 4-ring PAHs with a HPLC and growth curves of Bacillus sp. with a spectrophotometer. The results showed that both the effects depended on functional groups and concentrations of M-Pc, and rayon types. The most effective combination was observed in Fe-Pc with sulfo group supported on cationized rayon fiber at the concentration of 2 to 3.3 wt%. Central metal species of M-Pc were influenced only on the antibacterial properties. This fiber would be applicable to filtering agents and textiles.
    CHEMICAL & PHARMACEUTICAL BULLETIN 01/2015; 63(1):38-42. DOI:10.1248/cpb.c14-00542 · 1.38 Impact Factor
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    ABSTRACT: A new approach to ion chromatography is proposed to improve the UV detection of aliphatic carboxylic acids separated by anion-exchange chromatography. When copper(II) ion added to the mobile phase, it forms complexes with carboxylic acids that can be detected at 240nm. The absorbance was found to increase with increasing copper(II) ion concentration. The retention times of α-hydroxy acids were also found to depend on the copper(II) ion concentration. Addition of acetonitrile to the mobile phase improved the separation of aliphatic carboxylic acids. The detection limits of the examined carboxylic acids (formate, glycolate, acetate, lactate, propionate, 3-hydroxypropionate, n-butyrate, isobutyrate, n-valerate, isovalerate, n-caproate) calculated at S/N=3 ranged from 0.06 to 3μM. The detector signal was linear over three orders of magnitude of carboxylic acid concentration. The proposed method was successfully applied to analyze aliphatic carboxylic acids in rainwater and bread. Copyright © 2014 Elsevier B.V. All rights reserved.
    Journal of Chromatography A 12/2014; 1375. DOI:10.1016/j.chroma.2014.11.071 · 4.26 Impact Factor
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    ABSTRACT: The health effects associated with Asian dust have attracted attention due to the rapid increase in the number of Asian dust events in East Asia in recent years. The aim of this study was to investigate the associations between Asian dust and daily cough, as well as allergic symptoms, in adult patients who suffer from chronic cough. We enrolled 86 adult patients from Kanazawa University Hospital, Japan, who were diagnosed with asthma, cough variant asthma, atopic cough or a combination of these conditions. From January to June 2011, subjects recorded their symptoms in a diary every day. Asian dust and non-Asian dust periods were defined according to the dust extinction coefficient, measured using the light detection and ranging (LIDAR). The daily levels of total suspended particulates, polycyclic aromatic hydrocarbons (PAHs) and coexisting factors related to allergies, such as the Japanese cedar pollen count, were measured. McNemar's test showed that there were significantly more cough-positive patients during Asian dust periods than during the non-Asian dust period (p = 0.022). In addition, during Asian dust periods when the daily levels of Japanese cedar pollen, Japanese cypress pollen and PAHs were elevated, there were significantly more patients who experienced itchy eyes than during the non-Asian dust period (p < 0.05). On the other hand, there were no significant differences in the allergic symptoms, including sneezing or a runny nose and nasal congestion. This is the first report to show that Asian dust triggers cough and allergic symptoms in adult patients with chronic cough.
    Atmospheric Environment 11/2014; 97:537-543. DOI:10.1016/j.atmosenv.2014.01.041 · 3.06 Impact Factor
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    ABSTRACT: This study estimates atmospheric concentrations of chlorinated polycyclic aromatic hydrocarbons (ClPAHs) and polycyclic aromatic hydrocarbons (PAHs) in East Asia using a Gas Chromatograph with High Resolution Mass Spectrometer (GC-HRMS). ClPAHs are ubiquitously generated from PAHs through substitution, and some ClPAHs show higher aryl hydrocarbon receptor (AhR)-mediated activities than their parent PAHs. Atmospheric particles were collected using a high-volume air sampler equipped with a quartz-fiber filter. We determined the ClPAH concentrations of atmospheric particles collected in Japan (Sapporo, Sagamihara, Kanazawa, and Kitakyushu), Korea (Busan), and China (Beijing). The concentrations of ClPAHs were highest in the winter Beijing sample, where the total mean concentration was approximately 15–70 times higher than in the winter samples from Japan and Korea. The concentrations of Σ19ClPAHs and Σ9PAHs were significantly correlated in the Kanazawa and the Busan samples. This indicates that within those cities ClPAHs and PAHs share the same origin, implying direct chlorination of parent PAHs. Toxic equivalent concentrations (TEQs) of the total ClPAHs and PAHs were lowest in Kanazawa in the summer, reaching 1.18 and 2610 fg-TEQ m−3 respectively, and highest in Beijing in the winter, reaching 627 and 4 240 000 fg-TEQ m−3 respectively.
    Chemosphere 09/2014; 111:40–46. DOI:10.1016/j.chemosphere.2014.03.072 · 3.50 Impact Factor
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    ABSTRACT: Fumonisin A-series (FAs) in a reference material of corn sample that was naturally contaminated with fumonisins was characterized using high-resolution liquid chromatography-Orbitrap mass spectrometry (LC-Orbitap MS). Peaks for fumonisin B1 (FB1), fumonisin B2 (FB2), and fumonisin B3 (FB3), in addition to three peaks corresponding to unknown compounds I, II, and III, were detected in the chromatogram for the corn sample. Fragment ion analysis for FB1, FB2, and FB3 showed that while the ions formed at m/z values of 200-800 were similar to those formed by the cleavage of the tricarballylic acids and the hydroxyl groups, the fragmentation patterns at m/z values of 50-200 varied depending on the hydroxyl group locations in the compounds. Fragment ion analysis of compounds I-III revealed structural similarities to FBs, only differing by an additional C2H2O in the unknown compounds. Using these results and by comparing the product ion mass spectra of compound I with fumonisin A1 (FA1) synthesized from FB1 standards, compounds I-III were hypothesized to be N-acetyl analogs of FBs: fumonisins A1 (FA1), A2 (FA2), and A3 (FA3). The method for determining concentrations was validated with FA1, FB1, FB2, and FB3 standards and applied to analyze the reference material. The FB1, FB2, and FB3 analytical levels were within acceptance limits and the amount of FA1 in the material was ~15% of FB1 amount at 4.2 mg/kg.
    Toxins 08/2014; 6(8):2580-2593. DOI:10.3390/toxins6082580 · 2.48 Impact Factor
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    ABSTRACT: Asian dust, known as kosa in Japanese, is a major public health concern. In this panel study, we evaluated 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.
    Atmospheric Environment 07/2014; 97. DOI:10.1016/j.atmosenv.2014.04.034 · 3.06 Impact Factor
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    ABSTRACT: Airborne particulates were collected at a background site (Wajima Air Monitoring Station; WAMS) on the Noto Peninsula, Japan from January 2006 to December 2007. 1-, 2-nitropyrenes (1-, 2-NPs) and 2-nitrofluoranthene (2-NFR), in the particulates were determined with a sensitive HPLC method with chemiluminescence detection. The average concentrations were higher in winter than in summer. A meteorological analysis indicated that the air samples collected in winter were transported mainly from Northeast China over the Japan Sea. Both the concentration ratios of 2-NFR to 1-NP and 1-NP to pyrene were similar to those in Shenyang in Northeast China which located along the air transportation route to WAMS, but not in Kanazawa which near WAMS. These results strongly suggest that most of the atmospheric 1-, 2-NPs and 2-NFR at WAMS in winter were long range transported from Northeast China.
    Chemosphere 07/2014; 107. DOI:10.1016/j.chemosphere.2013.12.077 · 3.50 Impact Factor
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    ABSTRACT: Chiang Mai and several other provinces in northern Thailand have been annually facing air pollution problems during the dry season. Ten polycyclic aromatic hydrocarbons (PAHs); 19 nitropolycyclic aromatic hydrocarbons (NPAHs); and levoglucosan (LG), a marker for biomass burning, were quantified in total suspended particulates (TSP) collected in Chiang Mai during the dry, transition, and wet seasons in 2010. The concentrations of PAHs and NPAHs in the dry season were significantly higher than in the wet season. The [Benzo[a]pyrene (BaP)] – [benzo[ghi]perylene (BghiPe)] ratio, as an indicator of traffic, and the correlations of PAHs and NPAHs with LG showed that biomass burning significantly contributes to air pollution in the dry season. 9-Nitroanthracene (9-NA) was the most abundant NPAH which suggests that 9-NA is generated from biomass burning. We proposed the [9-NA] – [1-nitropyrene (1-NP)] ratio as a new indicator for assessing the contribution of biomass burning. Biomass burning was a major source of PAHs and NPAHs in the dry season, whereas vehicle exhaust was the main contribution in the wet season. The high carcinogenic risks in the dry season correlate with more harmful air conditions during this season. Thus, it is important to control biomass burning to reduce air-pollution-related health risks during the dry season in northern Thailand.
    Aerosol and Air Quality Research 06/2014; 14(4):1247-1257. DOI:10.4209/aaqr.2013.05.0161 · 2.66 Impact Factor
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    ABSTRACT: A variety of wild mushrooms were collected in a forest on the Noto Peninsula, Japan, to determine the concentration of 137Cs and 40K. The wild mushroom species belong to the orders Agaricales and Aphyllophorales. The concentration of 137Cs varied widely (1.4–4,100 Bq/kg dry weight) in mushrooms growing in soil. On the contrary, 137Cs concentration levels were relatively low (1.9–20 Bq/kg-dry weight) in mushrooms growing on wood. The concentration of 40K varied widely (12–2,400 Bq/kg-dry weight) in contrast with several previous reports that suggest relatively constant 40K levels in mushrooms. Unusually low concentrations of 40K were observed in a few mushroom species that had very hard fruiting bodies with peculiar shapes. The mean and median of 137Cs concentration in the present study were similar to those previously reported for Japanese mushrooms. Among the Agaricales mushrooms, Entolomataceae and Tricholomataceae families growing in soil had the highest concentration of 137Cs. Among the Aphyllophorales mushrooms, Gomphaceae and Ramariaceae families growing in soil also had the highest 137Cs concentrations. The concentrations of 137Cs and stable Cs in mushroom samples were positively correlated. The concentration ratio of 137Cs/Cs differed between Agaricales and Aphyllophorales mushrooms. The average 137Cs/Cs ratio in mushrooms growing in soil was similar to that calculated for the top soil (
    Journal of Radioanalytical and Nuclear Chemistry 05/2014; 300(2):707-717. DOI:10.1007/s10967-014-3060-y · 1.42 Impact Factor
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    ABSTRACT: To evaluate the effects of inorganic mercury (InHg) and methylmercury (MeHg) on bone metabolism in a marine teleost, the activity of tartrate-resistant acid phosphatase (TRAP) and alkaline phosphatase (ALP) as indicators of such activity in osteoclasts and osteoblasts, respectively, were examined in scales of nibbler fish (Girella punctata). We found several lines of scales with nearly the same TRAP and ALP activity levels. Using these scales, we evaluated the influence of InHg and MeHg. TRAP activity in the scales treated with InHg (10(-5) and 10(-4) M) and MeHg (10(-6) to 10(-4) M) during 6 hrs of incubation decreased significantly. In contrast, ALP activity decreased after exposure to InHg (10(-5) and 10(-4) M) and MeHg (10(-6) to 10(-4) M) for 18 and 36 hrs, although its activity did not change after 6 hrs of incubation. As in enzyme activity 6 hrs after incubation, mRNA expression of TRAP (osteoclastic marker) decreased significantly with InHg and MeHg treatment, while that of collagen (osteoblastic marker) did not change significantly. At 6 hrs after incubation, the mRNA expression of metallothionein, which is a metal-binding protein in osteoblasts, was significantly increased following treatment with InHg or MeHg, suggesting that it may be involved in the protection of osteoblasts against mercury exposure up to 6 hrs after incubation. To our knowledge, this is the first report of the effects of mercury on osteoclasts and osteoblasts using marine teleost scale as a model system of bone.
    ZOOLOGICAL SCIENCE 05/2014; 31(5):330-7. DOI:10.2108/zs130265 · 0.88 Impact Factor
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    ABSTRACT: Atmospheric particles were collected in several cities in Japan (Sapporo, Sagamihara, Kanazawa, and Kitakyushu), Korea (Busan), and China (Beijing) using a high-volume air sampler equipped with a quartz fiber filter. The summer and winter samples were analyzed using gas chromatography-high-resolution mass spectrometry for Dechlorane Plus (DP). Decabromodiphenyl ether (BDE-209) was also analyzed for the samples from Kanazawa and Beijing. DP was detected in all samples. The mean total DP (ΣDP) concentration was highest (6.7 pg/m(3)) and lowest (0.87 pg/m(3)) in the winter samples from Sagamihara and Busan, respectively. The seasonal variation of DP concentrations varied by sampling site in this study. BDE-209 was detected in all the analyzed samples except for one of the Kanazawa winter samples. BDE-209 concentration was considerably higher in Beijing than in Kanazawa. Significant correlations were found between the concentrations of ΣDP and BDE-209 in the winter samples from Kanazawa and in both summer and winter samples from Beijing. This similarity in the atmospheric behavior of DP and BDE-209, especially in winter, is assumed to reflect a common end usage and release mechanism.
    Environmental Science and Pollution Research 04/2014; DOI:10.1007/s11356-014-2861-4 · 2.76 Impact Factor
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    ABSTRACT: We recently demonstrated that prostaglandin E, (PG,) increases osteoclastic activity and induces bone resorptionin both in vitro and in vivo experiments using goldfish. In the fish reproductive period, the plasma calcium 〔Ca)level in female teleosts increases remarkably to make vitellogenin,which is a major component of egg protein and a Ca-binding protein. In this period, however, there is no reported relationship between PGE, and Ca metabolism in fish. To clarify the Ca metabolism in fish reproduction, we examined plasma PGE2 and Ca levels and measured tartrate-resistant acid phosphatase (TRAP〕activitiesas an indicator of osteoclastic activity in goldfish. Plasma PGE, levels in the reproductive stage significantly increased as compared with those in non-reproductive stages. Also, both plasma Ca and TRAP increased in the reproductive stage. Significant positive correlations were recognized between plasma Ca and the gonad somatic index (r=0.81, pく0.001〕, plasmaCa and plasma PGE2 levels (γ=0.635,pく0.05),and plasma Ca and plasma TRAP activities (γ=0.584, pく0.05)from the analysis using samples of both reproductive and nonreproductive stages. Taking these data into consideration, we suggested that PGE2 acts on osteoclasts and increases plasma Ca as a result of osteoclastic bone resorption, and we concluded that PGE2 is an important hormone in Ca metabolism during fish reproduction.
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    ABSTRACT: Polycyclic aromatic hydrocarbon quinones (PAHQs) are components in airborne particulate matter (PM) and generate reactive oxygen species (ROS) in a redox cycling process. 9,10-Phenanthrenequinone (9,10-PQ) is a PAHQ found in diesel exhaust particulates and PM. When inhaled, it produces much more ROS than other PAHQs. We hypothesized that urinary metabolites of 9,10-PQ could serve as biomarkers of PAHQ exposure. Here, we describe methods for pretreating urine samples and analyzing 9,10-PQ metabolites by liquid chromatography with tandem mass spectrometry (LC-MS/MS). In urine from rats intraperitoneally injected with 9,10-PQ, the monoglucuronide of 9,10-dihydroxyphenanthrene (9,10-PQHG) was found to be a major metabolite of 9,10-PQ. 9,10-PQHG was also identified in the urine of a nonoccupationally exposed human by its retention time and MS/MS spectra. Furthermore, the urine contained hardly any free (unmetabolized) 9,10-PQ, but treating it with hydrolytic enzymes released 9,10-PQ from conjugated metabolites such as 9,10-PQHG. The concentrations of 9,10-PQHG in urine samples from nonoccupationally exposed subjects who lived in a suburban area were 2.04-19.08 nmol/mol creatinine. This study is the first to demonstrate the presence of 9,10-PQHG in human urine. Determination of urinary 9,10-PQHG should be useful for determining 9,10-PQ exposure.
    Chemical Research in Toxicology 01/2014; 27(1):76-85. DOI:10.1021/tx400338t · 4.19 Impact Factor
  • Bunseki kagaku 01/2014; 63(1):23-29. DOI:10.2116/bunsekikagaku.63.23 · 0.22 Impact Factor
  • Bunseki kagaku 01/2014; 63(5):371-382. DOI:10.2116/bunsekikagaku.63.371 · 0.22 Impact Factor

Publication Stats

3k Citations
589.15 Total Impact Points


  • 1982–2015
    • Kanazawa University
      • • Graduate School of Natural Science and Technology
      • • Department of Molecular Pharmacology
      Kanazawa, Ishikawa, Japan
  • 2013
    • Japan Aerospace Exploration Agency
      Chōfu, Tōkyō, Japan
  • 2008–2013
    • Nagoya City University
      • Graduate School of Pharmaceutical Sciences
      Nagoya, Aichi, Japan
  • 2012
    • Agilent Technologies
      Santa Clara, California, United States
  • 2007–2011
    • Chubu University
      • • College of Bioscience and Biotechnology
      • • Department of Biological Chemistry
      Kasugai, Aichi-ken, Japan
  • 2010
    • Kanazawa Medical University
      Kanazawa, Ishikawa, Japan
  • 2006
    • University of Washington Seattle
      Seattle, Washington, United States
    • Waters Corporation
      Milford, Massachusetts, United Kingdom