- 著者
- Takuma Yamamoto Katsuhiko Yoshizawa Shin-ichi Kubo Yuko Emoto Kenji Hara Brian Waters Takahiro Umehara Takehiko Murase Kazuya Ikematsu
- 出版者
- 日本毒性病理学会
- 雑誌
- Journal of Toxicologic Pathology (ISSN:09149198)
- 巻号頁・発行日
- vol.28, no.1, pp.33-36, 2015 (Released:2015-02-24)
- 参考文献数
- 17
- 被引用文献数
- 3 34
Caffeine (1,3,7-trimethylxanthine) is a popular mild central nervous system stimulant found in the leaves, seeds and fruits of various plants and in foodstuffs such as coffee, tea, and chocolate, among others. Caffeine is widely used and is not associated with severe side effects when consumed at relatively low doses. Although rarely observed, overdoses can occur. However, only a few fatal caffeine intoxication cases have been reported in the literature. Herein, we report the pathological examination results and information on caffeine concentrations in the blood, urine and main organs in a fatal caffeine intoxication case. Even though high caffeine concentrations were found in the systemic organs, no caffeine-related pathological changes were detected.
- 著者
- Takako GOTOHDA Aki KUWADA Kyoji MORITA Shin-ichi KUBO Itsuo TOKUNAGA
- 出版者
- The Japanese Society of Toxicology
- 雑誌
- The Journal of Toxicological Sciences (ISSN:03881350)
- 巻号頁・発行日
- vol.25, no.3, pp.223-231, 2000-08-17 (Released:2008-02-21)
- 参考文献数
- 39
- 被引用文献数
- 11 12
Toluene, a commonly used industrial solvent, is known to be toxic to both neuronal and glial cells, and has been shown to increase the immunoreactivity of glial fibrillary acidic protein(GFAP)in the brain. However, the mechanism of toluene-induced GFAP expression is poorly understood. Recently, GFAP mRNA expression in cultured astrocytes has been shown to be modulated by various steroid hormones, such as progesterone, testosterone, and their 5α-reduced metabolites. Therefore, it seems possible that steroid hormones may play a potential role in the enhancement of GFAP expression observed following toluene exposure. To address this possibility, the effect of toluene inhalation on the expression of mRNAs encoding GFAP and steroidogenic enzymes in rat brain was examined. Toluene exposure increased GFAP protein contents without any significant alteration in GFAP mRNA levels in the hippocampus. In contrast, the elevation of both GFAP protein contents and its mRNA levels was observed in the cerebellum following toluene exposure. Further studies indicated that toluene exposure increased steroid 5α-reductase(5α-R)mRNA levels prior to the elevation of GFAP mRNA in the cerebellum, whereas neither 5α-R nor GFAP mRNA levels in the hippocampus were significantly affected by toluene exposure. These results suggest that toluene inhalation may enhance GFAP gene expression in the rat cerebellum, and propose the possibility that the elevation of 5α-R expression, and hence 5α-reduced metabolites of steroid hormones, is presumably related to toluene-induced GFAP mRNA expression.
- 著者
- Brian Waters Kenji Hara Natsuki Ikematsu Mio Takayama Aya Matsusue Masayuki Kashiwagi Shin-ichi Kubo
- 出版者
- 日本法科学技術学会
- 雑誌
- 日本法科学技術学会誌 (ISSN:18801323)
- 巻号頁・発行日
- vol.23, no.2, pp.125-131, 2018 (Released:2018-07-30)
- 参考文献数
- 19
- 被引用文献数
- 1
The aim of this study was to develop a practical method to analyze tetrodotoxin (TTX), quantitatively, from postmortem specimens, not only blood and urine, but also organs. Extraction was achieved with 2% acetic acid and the use of an anion-exchange solid-phase extraction (SPE) cartridge. The quantitation method was a standard addition method with a calibration curve consisting of at least 3 points and an internal standard, voglibose (VOG). Separation by LC-MS/MS was achieved using a Luna HILIC (Phenomenex) column. The mobile phase was acetonitrile: 5 mM ammonium formate buffer (95:5), delivered at 0.2 mL/min. The selected reaction monitoring (SRM) transitions for TTX and VOG were m/z 320>302 and m/z 268>92, respectively. Cleaner extracts were achieved by using a lipid removal cartridge and washing with heptane. The addition of steps to remove interfering components that are prominent in postmortem samples aided in successful analysis. The HILIC column improved the retention of TTX to greater than 2 min to avoid the area where ion suppression has its greatest effect. Also, the use of anion-exchange SPE lessened the influence of acetic acid used during extraction. By using this method, we were able to quantitate low levels of TTX in postmortem specimens.