著者

Tsutomu Shimura Ichiro Yamaguchi Hiroshi Terada Toshihiko Yunokawa Erik Robert Svendsen Naoki Kunugita

出版者

内閣府食品安全委員会

雑誌

Food Safety (ISSN:21878404)

巻号頁・発行日

vol.3, no.3, pp.84-91, 2015 (Released:2015-09-29)

参考文献数

21

被引用文献数

2

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Herein we analyzed food monitoring data regarding the Fukushima accident. The Japanese government ordered local governments to implement food monitoring after the Fukushima nuclear accident. This protective action for food safety contributed to the reduction of internal radiation exposure derived from the Fukushima accident. According to the food monitoring data collected from March 2011 to March 2015, more than 70% of the samples were beef. One hundred fifty four samples from a total of 776,310 beef samples that were above provisional regulation values or new standard limits were restricted from market distribution. Most of the beef samples were below the detection limits by regulation of consumption of contaminated rice straw. Two hundred forty one from a total of 251,510 beef samples were above the detection limit during fiscal year 2014. The mean committed effective dose due to annual beef consumption was estimated to be 1 µSv. The 99.9 percentile committed effective dose was 20 µSv. Thus, internal exposure due to beef consumption is limited. However, local governments continue regular monitoring for beef in response to social concerns. It should be noted that continuous staff effort and high costs are required to maintain this food surveillance program. A formal evaluation may help to assist in the development of a more effective and efficient food monitoring system.

著者

Hiroshi Akiyama Hideki Matsuoka Takanori Okuyama Kyohei Higashi Toshihiko Toida Hiroyuki Komatsu Yoshiko Sugita-Konishi Satomi Kobori Yukio Kodama Midori Yoshida Hitoshi Endou

出版者

内閣府食品安全委員会

雑誌

Food Safety (ISSN:21878404)

巻号頁・発行日

vol.3, no.1, pp.16-29, 2015 (Released:2015-03-30)

参考文献数

37

被引用文献数

6

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A novel type of encephalopathy associated with the ingestion of Sugihiratake mushroom (Pleurocybella porrigens) occurred in patients with chronic renal failure treated on hemodialysis in fall, 2004 in Japan. To clarify the mechanism of encephalopathy onset, we, for the first time, purified the cyanogen glycoside fraction (CG) from Sugihiratake mushroom using reversed phase high-performance liquid chromatography and hydrophilic interaction chromatography. Furthermore, we investigated single dose toxicity of the CG in an adenine-induced rat model of chronic renal damage (CRD). Pathological examination of kidneys indicates the development of CRD. Oral administration of the CG induces the accumulation of thiocyanate in the hemolyzed blood and brain in CRD rats, although no morphological changes were found in the brain. No further enhancement of kidney damage is observed after the oral administration of the CG in CRD rats. This is the first experimental report to suggest that acute encephalopathy, induced by Sugihiratake mushroom intake in the patients with chronic renal failure, is associated with intoxication of cyanide and thiocyanate, presumably produced metabolically produced after the ingestion of Sugihiratake mushroom.

著者

Justin J. Greenlee Robert A. Kunkle Jodi D. Smith M. Heather West Greenlee

出版者

内閣府食品安全委員会

雑誌

Food Safety (ISSN:21878404)

巻号頁・発行日

vol.4, no.4, pp.110-114, 2016 (Released:2016-12-22)

参考文献数

33

被引用文献数

8

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A naturally occurring prion disease has not been recognized in swine, but the agent of bovine spongiform encephalopathy does transmit to swine by experimental routes. Swine are thought to have a robust species barrier when exposed to the naturally occurring prion diseases of other species, but the susceptibility of swine to the agent of sheep scrapie has not been thoroughly tested. We conducted this experiment to test the susceptibility of swine to U.S. scrapie isolates by intracranial and oral inoculation. Scrapie inoculum was a pooled 10% (w/v) homogenate derived from the brains of clinically ill sheep from the 4th passage of a serial passage study of the U.S scrapie agent (No. 13–7) through susceptible sheep (homozygous ARQ at prion protein residues 136, 154, and 171, respectively). Pigs were inoculated intracranially (n=19) with a single 0.75 mL dose or orally (n=24) with 15 mL repeated on 4 consecutive days. Necropsies were done on a subset of animals at approximately six months post inoculation (PI): the time the pigs were expected to reach market weight. Remaining pigs were maintained and monitored for clinical signs of transmissible spongiform encephalopathies (TSE) until study termination at 80 months PI or when removed due to intercurrent disease (primarily lameness). Brain samples were examined by immunohistochemistry (IHC), western blot (WB), enzyme immunoassay (EIA), and for a subset of pigs in each inoculation group, bioassay in mice expressing porcine prion protein. At six-months PI, no evidence of scrapie infection was noted by any diagnostic method. However, at 51 months of incubation or greater, 5 animals were positive by one or more methods: IHC (n=4), WB (n=3), or EIA (n=4). Furthermore, positive bioassay results were obtained from all inoculated groups (oral and intracranial; market weight and end of study) suggesting that swine are potential hosts for the agent of scrapie.

著者

Yasuhisa Ano Akikazu Sakudo Ryuta Uraki Juri Kono Masayoshi Yukawa Takashi Onodera

出版者

内閣府食品安全委員会

雑誌

Food Safety (ISSN:21878404)

巻号頁・発行日

vol.1, no.1, pp.2013005-2013005, 2013 (Released:2013-11-20)

参考文献数

51

被引用文献数

3

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Infectious prion diseases include Kuru and its variant, Creutzfeldt-Jakob disease, in humans, scrapie in sheep, and bovine spongiform encephalopathy in cattle. In these diseases, the pathogenic prion protein (PrPSc) enters the host through the gastrointestinal tract and migrates to the central nervous system, where PrPSc induces characteristic pathological changes. The mechanisms underlying this intercellular transfer are not fully understood. After oral administration, PrPSc withstands the digestive process and may be incorporated by microfold cells (M cells) or villous columnar epithelial cells in the intestine. Based on Western Blot with specific markers, liquid chromatography, and morphological analysis, the cellular prion protein (PrPC) and PrPSc in the cells are associated with exosomes, membranous vesicles that are secreted upon fusion of multivesicular endosomes with the plasma membranes. Exosomes may play a role in PrP transportation through intestinal epithelium. Cells may exploit the nature of endosome-derived exosomes to communicate with each other in normal and pathological situations, providing for a novel route of cell-to-cell communication and therefore of pathogen transmission in the intestinal epithelium. In addition, since most bovine spongiform encephalopathy cases were exposed to the agent in the first six months of life, developmental alteration of the intestinal defense and immune system may also be involved in the susceptibility to infection.