Naoki Arizono

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Protease-activated receptor-2 (PAR-2), a receptor activated by trypsin/tryptase, modulates smooth muscle tone and exocrine secretion in the salivary glands and pancreas. Given that PAR-2 is expressed throughout the gastrointestinal tract, we investigated effects of PAR-2 agonists on mucus secretion and gastric mucosal injury in the rat. PAR-2-activating(More)
Protease-activated receptor-2, a G protein-coupled receptor activated by serine proteases such as trypsin, tryptase and coagulation factors VIIa and Xa, modulates pancreatic and salivary exocrine secretion. In the present study, we examined the distribution of PAR-2 in the pancreas and parotid gland, and characterized the PAR-2-mediated secretion of amylase(More)
Diphyllobothrium nihonkaiense [Y. Yamane, H. Kamo, G. Bylund, J.P. Wilkgren. Diphyllobothrium nihonkaiense sp. nov (Cestoda: Diphyllobothriidae)- revised identification of Japanese broad tapeworm. Shimane J Med Sci 1986;10:29-48.] and Diphyllobothrium klebanovskii [I.V. Muratov, P.S. Posokhov. Causative agent of human diphyllobothriasis - Diphyllobothrium(More)
C57BL/6 (B6) and B6 background STAT6(-/-) mice pretreated with IL-18 plus IL-2 showed prominent intestinal mastocytosis and rapidly expelled implanted adult worms of the gastrointestinal nematode Strongyloides venezuelensis. In contrast, identically pretreated mast cell-deficient W/W(v) mice failed to do so. Thus, activated mucosal mast cells (MMC) are(More)
Human ascariasis is caused by infection with the common roundworm Ascaris lumbricoides, although the pig roundworm Ascaris suum has also been reported to infect humans and develop into the adult stage. To elucidate whether pig-derived Ascaris infects humans in Japan, 9 Ascaris isolates obtained from Japanese patients and a further 9 Ascaris isolates of pig(More)
The surface lining cells in the gastric and the intestinal mucosa, arising from the proliferative cell zone at the neck region of glands and in the crypts, respectively, are renewed in 3-5 days. There is a diurnal rhythm in the proliferation of the precursor cells; more surface lining cells arise in the daytime. This results in sloughing of more cells. In(More)
The incidence of human infection with the broad tapeworm Diphyllobothrium nihonkaiense has been increasing in urban areas of Japan and in European countries. D. nihonkaiense is morphologically similar to but genetically distinct from D. latum and exploits anadromous wild Pacific salmon as its second intermediate host. Clinical signs in humans include(More)
A 5-year-old Japanese boy passed tapeworm strobila while he was living in Switzerland. During a short visit to Japan, he was successfully treated with a single dose of praziquantel. DNA sequences of ITS1, cox1 and nd3 genes from the tapeworm were compatible with those of Diphyllobothrium nihonkaiense rather than Diphyllobothrium latum, which is prevalent in(More)
While investigating the effect of marine products on cell growth, we found that visceral extracts of Chub mackerel, an ocean fish, had a powerful and dose-dependent apoptosis-inducing effect on a variety of mammalian tumor cells. This activity was strikingly dependent on infection of the C. mackerel with the larval nematode, Anisakis simplex. After(More)
Anisakiasis is one of the most common fishborne helminthic diseases in Japan, which is contracted by ingesting the larvae of the nematode Anisakis spp. carried by marine fish. Anisakis simplex sensu stricto (s.s.) and A. pegreffii are the dominant species in fish caught offshore Japan. The present study aimed to identify the anisakid species infecting(More)