Publications by authors named "Chihiro Ishii"

Although lead (Pb) poisoning in wild birds has been considered a serious problem in Japan for over 30 years, there is little information about Pb exposure and its sources throughout Japan except for Hokkaido. Furthermore, to identify and effectively prioritize the conservation needs of highly vulnerable species, differences in sensitivity to Pb exposure among avian species need to be determined. Therefore, we investigated the current situation of Pb exposure in raptors (13 species, N = 82), waterfowl (eight species, N = 44) and crows (one species, N = 6) using concentration and isotope analysis.

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Male and female reproductive tracts develop from anterior intermediate mesoderm with similar differentiation processes. The anterior intermediate mesoderm develops into the mesonephros, and the Wolffian duct initiates by epithelialization in the mesonephros. The Müllerian duct invaginates from the coelomic epithelium of the cranial mesonephros for ductal formation and is then regionalized into proximal to caudal female reproductive tracts.

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Bird death is often caused by renal lesions induced by chemicals. The avian kidney has a renal portal system with significant blood flow that is sensitive to many chemicals. However, early avian biomarkers for kidney injury are yet to be identified.

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Among wild birds, lead (Pb) exposure caused by ingestion of ammunition is a worldwide problem. We aimed to reveal the behavior and toxic effect of Pb caused by ingesting Pb shots in waterfowl. Four male, eight-week old Muscovy ducks (Cairina moschata) were given three Pb shots (approximately 240 mg in total) orally and then fed for 29 days after exposure, simulating a low-dose Pb exposure in wild waterfowl.

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Lead poisoning of wild birds by ingestion of lead ammunition occurs worldwide. Histopathological changes in organs of lead-intoxicated birds are widely known, and lead concentration of each organ is measurable using mass spectrometry. However, detailed lead localization at the suborgan level has remained elusive in lead-exposed birds.

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Birds of a number of species have died as a result of lead (Pb) poisoning, including many Steller's sea eagles (Haliaeetus pelagicus) and white-tailed sea eagles (Haliaeetus albicilla) in Hokkaido, the northernmost island of Japan. To address this issue, the use of any type of Pb ammunition for hunting of large animals was prohibited in Hokkaido in 2004. However, Pb poisoning is still being reported in this area, and there are few regulations regarding the use of Pb ammunition in other parts of Japan, where it has been reported that eagles and water birds have been exposed to Pb.

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Worldwide use of anticoagulant rodenticides (ARs) for rodents control has frequently led to secondary poisoning of non-target animals, especially raptors. In order to suggest some factors that may help considering the mechanism of the incidents, this study focused on the avian vitamin K 2, 3-epoxide reductase (VKOR) that is the target protein of ARs. We addressed the interspecific differences in VKOR activity and inhibition related to amino acid sequence and mRNA expression of VKORC1 and VKORC1-like1 (VKORC1L1).

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Lead (Pb) poisoning in raptors and water birds is a serious problem in many countries. However, only a small fraction of Pb poisoning has been detected in birds. Bone specimens may be useful indices of Pb exposure because bones contain ∼90% of the total Pb body burden.

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Lead (Pb) poisoning is widespread among raptors and water birds. In Japan, fragments of Pb ammunition are still found in endangered eagles although more than 10 years have passed since legislation regarding use of Pb ammunition was introduced. This study was performed to investigate Pb exposure in raptors from various locations in Japan.

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Seabirds are marine top predators and accumulate high levels of metals and metalloids in their tissues. Contamination by metals in the highly productive offshore region has become a matter of public concern. It is home to 80% of the seabird population in the U.

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Nairobi city in Kenya produces 2000 tons/day of garbage, and most of it is dumped onto the Dandora dumping site, home to a quarter-million residents. This study was conducted (1) to assess the contamination levels of nine metals and a metalloid (arsenic) in the blood of pigs, goats, sheep and cattle from Dandora, and (2) to identify a possible source of lead (Pb) pollution. Cadmium (Cd, 0.

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Coumarin-derivative anticoagulant rodenticides used for rodent control are posing a serious risk to wild bird populations. For warfarin, a classic coumarin derivative, chickens have a high median lethal dose (LD50), whereas mammalian species generally have much lower LD50. Large interspecies differences in sensitivity to warfarin are to be expected.

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Teuri Island, Hokkaido in Japan is an important place for seabirds breeding. We measured the concentrations of heavy metals (Hg, Cd, Cr, Co, Ni, Cu, Zn, and Pb) and a metalloid (As) in rhinoceros auklet (Cerorhinca monocerata) (n = 7), thick-billed murre (Uria lomvia) (n = 2), spectacled guillemot (Cepphus carbo) (n = 6), slaty-backed gull (Larus schistisagus) (n = 15), jungle crow (Corvus macrorhynchos) (n = 3), Japanese anchovy (Engraulis japonica) (n = 6) and Atka mackerel (Pleurogrammus azonus) (n = 2). Spectacled guillemot had high As concentrations, with its source being their feeding habitat.

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It is reported that seabirds accumulate high levels of metals, prompting concerns regarding poisoning. The present study investigated the accumulation patterns of metals in tissues among four species of seabirds (Fratercula corniculata, Uria lomvia, Puffinus tenuirostris, and Fulmarus glacialis). Furthermore, we focused on Slaty-backed Gulls, which accumulated high levels of cadmium and mercury, and compared the areal differences.

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The Epstein-Barr virus (EBV)-encoded oncoprotein latent membrane protein 1 (LMP1) has an essential role in B-lymphocyte transformation by the virus and is expressed in certain EBV-associated tumors and lymphoproliferative disorders. By using the Flp-In/TREx-inducible expression system, we introduced LMP1 into two human cell lines, Jurkat and HEK-293, and found that in both of them the putative cellular oncogene Bcl-3 is rapidly induced following the expression of LMP1. Bcl-3 was also induced in Ramos cells after in vitro EBV infection and after transfection with an LMP1 expression vector.

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The crystal structure of congerin II, a galectin family lectin from conger eel, was determined at 1.45A resolution. The previously determined structure of its isoform, congerin I, had revealed a fold evolution via strand swap; however, the structure of congerin II described here resembles other prototype galectins.

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An expression system for recombinant conger eel galectins, congerins I and II, were constructed using the pTV 118N plasmid vector and Escherichia coli. Recombinant congerins I and II could be obtained in the soluble active form with high quantitative yield. Mutation of codons for Val and Leu located in the N-terminal region of Con I increased the expression efficiency.

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