5 0 0 0 OA 水産品のリステリア汚染
- 著者
- 中村 寛海 西川 禎一
- 出版者
- Osaka Urban Living and Health Association
- 雑誌
- 生活衛生 (ISSN:05824176)
- 巻号頁・発行日
- vol.50, no.4, pp.175-184, 2006 (Released:2006-08-08)
- 参考文献数
- 39
- 被引用文献数
- 2
Listeria monocytogenes is the causative agent of foodborne listeriosis in humans. Japan has an average of 83 cases of listeriosis per year and an estimated incidence of 0.65 cases per million residents, which is lower than the values reported in some European countries and the United States. Nevertheless, the level of contamination in retail food products in Japan is roughly equivalent to that reported in these countries, where large outbreaks have occurred. Japan might therefore face a similar risk of foodborne listeriosis outbreaks. Ready-to-eat seafood (such as cold-smoked fish) has been linked to sporadic cases of listeriosis. In Japan, a wide range of ready-to-eat seafood products are consumed in great quantities. We investigated L. monocytogenes contamination in commercially available ready-to-eat seafood products during 1999 and 2000. L. monocytogenes was isolated from 13% (12 of 95) of the tested products. All the positive samples were cold-smoked fish products. Molecular typing of the isolates suggested that the products were contaminated with persistent strains that were unique to their respective manufacturers. We investigated manufacturing plant A to trace L. monocytogenes isolates to the source of contamination. As the result of this, a combined analysis of the seasonal prevalence of this bacterium and molecular typing of the isolates in the plant suggested that the product contamination was associated with the slicing machines. Implementation of an effective washing and cleaning regime for the slicing machines resulted in a marked decrease in the incidence of L. monocytogenes contamination of the finished products.
3 0 0 0 OA NK (ナチュラルキラー) 細胞と食品成分
- 著者
- 西川 禎一
- 出版者
- The Japanese Society of Nutrition and Dietetics
- 雑誌
- 栄養学雑誌 (ISSN:00215147)
- 巻号頁・発行日
- vol.62, no.3, pp.129-144, 2004-06-01 (Released:2010-02-09)
- 参考文献数
- 103
Elucidation of the function and mechanism of the innate immune system has shown that natural killer (NK) cells play an important role, particularly for protection against viral infection and cancer; they also seem to participate in maintaining the health of senescent people and their longevity. The fundamental aspects of innate immunity and NK cells is explained first in this review. Bibliographic information on effective nutrient composition, food ingredients, and life style for activating NK cells is then presented and explained.
1 0 0 0 OA 非定型下痢原性大腸菌について 1
- 著者
- 涌嶋 三津子 王 麗麗 日高 あゆみ 藤原 佐美 中島 涼 石 娟娟 西川 禎一
- 出版者
- Osaka Urban Living and Health Association
- 雑誌
- 生活衛生 (ISSN:05824176)
- 巻号頁・発行日
- vol.54, no.4, pp.271-284, 2010-10-30 (Released:2010-11-10)
- 参考文献数
- 57
Escherichia coli is a normal inhabitant of the intestinal tract in humans and warm-blooded animals; however, certain strains cause enteric disease in their hosts and are referred to as diarrheagenic E. coli (DEC). Based on distinct epidemiological and clinical features, specific virulence determinants, and other characteristic markers such as enterotoxins and adherence phenotype, DEC strains have been classified into the following six pathotypes: enteropathogenic E. coli; Shiga toxin-producing E. coli; enterotoxigenic E. coli (ETEC); enteroinvasive E. coli; enteroaggregative E. coli (EAEC); and diffusely adhering E. coli. E. coli that does not have any diarrheagenic characteristics other than the EAEC heat-stable toxin 1 (EAST1) gene is defined as EASTEC. Although EAST1 has not been widely accepted as a virulence factor, we focused our attention on EASTEC because outbreaks due to EASTEC O166:H15 have occurred in several cities since the first incident in Osaka, Japan, in 1996. In the present review, we discuss EASTEC as a possible seventh group of DEC. Guanylin is secreted in the colon and acts physiologically as an agonist of the guanylyl cyclase receptor to regulate electrolyte and water transport in the epithelia. EAST1, like the heat-stable enterotoxins of ETEC, may mimic guanylin and cause diarrhea. However, epidemiological studies show that the EAST1 gene (astA) is very prevalent not only among EASTEC strains from diarrheal patients but also in healthy people, domestic animals, and meat products. The presence of astA itself may therefore not necessarily indicate that the strain will be diarrheagenic in the intestine. Production of active EAST1 should be checked since astA seems to have numerous variants. The development of a convenient assay for EAST1 is essential. Further epidemiological studies are also required to elucidate whether EASTEC forms a seventh group of DEC; such studies would also identify additional virulence traits such as colonization factor.
1 0 0 0 OA 非定型下痢原性大腸菌について 2
- 著者
- 有川 健太郎 西川 禎一
- 出版者
- Osaka Urban Living and Health Association
- 雑誌
- 生活衛生 (ISSN:05824176)
- 巻号頁・発行日
- vol.55, no.1, pp.15-22, 2011-03-10 (Released:2011-03-18)
- 参考文献数
- 38
Diarrheagenic Escherichia coli (DEC) is an important group of pathogens associated with enteric diseases. Diffusely adherent Escherichia coli (DAEC) strains are currently considered to constitute a sixth group of DEC. Although recent epidemiological studies have shown a high prevalence of DAEC strains among strains isolated from infant diarrheal stools, their involvement remains a matter of debate. Both commensal and pathogenic strains can be classified as Afa/Dr DAEC isolates since DAEC strains have been identified based on their diffuse adherence (DA) to cultured epithelial cells and on the detection of afa/dra/daa related operons encoding the DA phenotype. Measuring diffuse adhesion alone is insufficient to evaluate the diarrheagenicity of strains and other distinguishing characteristics are needed. In order to elucidate the pathophysiological processes by which Afa/Dr DAEC strains induce diarrhea, the present review focuses on the Afa/Dr adhesin and the various cell signaling events that occur after epithelial cells have been infected by Afa/Dr DAEC.
- 著者
- 小西 典子 尾畑 浩魅 甲斐 明美 大塚 佳代子 西川 禎一 寺嶋 淳 工藤 由起子
- 出版者
- 公益社団法人 日本食品衛生学会
- 雑誌
- 食品衛生学雑誌 (ISSN:00156426)
- 巻号頁・発行日
- vol.59, no.4, pp.161-166, 2018-08-25 (Released:2018-08-30)
- 参考文献数
- 29
- 被引用文献数
- 2
腸管毒素原性大腸菌(ETEC)は,発展途上国において一般的な病原体として知られており,汚染した野菜や水を介して食中毒を引き起こす.また,ETECは,先進国でも食中毒を引き起こすが,その原因食品はしばしば不明である.そこで,食中毒統計を基に日本で発生したETEC食中毒事例を分析した.その結果,野菜および井戸水が原因食品の50%および22.2%を占めた.これら主な原因食品は発展途上国の場合と同様であった.また,ETECの血清群も分析され,血清群O6,O25,O27,O148,O153,O159およびO169が主要7血清群であった.ETECの代表的な血清群O148による食中毒発生事例について,その食品での検査法を中心に詳細に検討した結果,二段階増菌法および耐熱性エンテロトキシン遺伝子を対象としたリアルタイムPCR法によって本菌が効率的にカットネギから検出された.本研究では,日本でのETEC食中毒の原因食品および主要O血清群が明らかになり,ETECの国内環境での生存が示唆された.また,食中毒事例での原因食品究明において効果的な検出法が示された.