Nitro-PAHs and PAHs in Atmospheric Particulate Matters and Sea Sediments in Hiroshima Bay Area, Japan     

Noriatsu Ozaki  Nobuya Takemoto  Tomonori Kindaichi 《Water, air, and soil pollution》2010,207(1-4):263-271

Atmospheric and sea sediment concentrations were measured for eight nitrated polycyclic aromatic hydrocarbons (nitro-PAHs) and three unsubstituted PAHs in a suburban area and sea sediments in the Hiroshima Bay watershed area, Japan, from July to December, 2006 (atmospheric particulate matter) and in September and November, 2004 (sea sediments). Atmospheric concentration was higher in winter than summer for both nitro-PAHs and PAHs. Concentrations in sea sediments were less than 10%, and pattern was similar to those of atmospheric particles. Several combustion emission sources were also measured, and the 1-NP/Pyr ratio was compared to environmental values. The ratio of atmospheric and sea sediments were significantly lower than diesel particulate matters. Further, the vehicle emission loading and sea sedimentation loading was evaluated in this watershed area, and from the comparison, the existence of other important sources PAHs were suggested.  相似文献   

Molecular epidemiology of avian influenza viruses circulating among healthy poultry flocks in farms in northern Vietnam     

Takakuwa H  Yamashiro T  Le MQ  Phuong LS  Ozaki H  Tsunekuni R  Usui T  Ito H  Morimatsu M  Tomioka Y  Yamaguchi T  Ito T  Murase T  Ono E  Otsuki K 《Preventive veterinary medicine》2012,103(2-3):192-200

Repeated epizootics of highly pathogenic avian influenza (HPAI) virus subtype H5N1 were reported from 2003 to 2005 among poultry in Vietnam. More than 200 million birds were killed to control the spread of the disease. Human cases of H5N1 infection have been sporadically reported in an area where repeated H5N1 outbreaks among birds had occurred. Subtype H5N1 strains are established as endemic among poultry in Vietnam, however, insights into how avian influenza viruses including the H5N1 subtype are maintained in endemic areas is not clear. In order to determine the prevalence of different avian influenza viruses (AIVs), including H5N1 circulating among poultry in northern Vietnam, surveillance was conducted during the years 2006-2009. A subtype H5N1 strain was isolated from an apparently healthy duck reared on a farm in northern Vietnam in 2008 and was identified as an HPAI. Although only one H5N1 virus was isolated, it supports the view that healthy domestic ducks play a pivotal role in maintaining and transmitting H5N1 viruses which cause disease outbreaks in northern Vietnam. In addition, a total of 26 AIVs with low pathogenicity were isolated from poultry and phylogenetic analysis of all the eight gene segments revealed their diverse genetical backgrounds, implying that reassortments have occurred frequently among strains in northern Vietnam. It is, therefore, important to monitor the prevalence of influenza viruses among healthy poultry between epidemics in an area where AIVs are endemic.  相似文献   

Inhibitory effects of citrus essential oils and their components on the formation of N-nitrosodimethylamine   总被引：1，自引：0，他引：1  

Sawamura M  Sun SH  Ozaki K  Ishikawa J  Ukeda H 《Journal of agricultural and food chemistry》1999,47(12):4868-4872

Twenty-eight kinds of citrus essential oils and their components were studied for inhibitory effects on the formation of N-nitrosodimethylamine (NDMA). The reaction mixture consisted of dimethylamine and sodium nitrite adjusted at pH 3.6, in addition to essential oils and an emulsifying agent. The quantification was determined by high-performance liquid chromatography monitored at 220 nm. All of the essential oils inhibited the formation of NDMA in the range of 20-85%. The oils of ujukitsu (Citrus ujukitsu Hort. ex Shirai), yuzu (C. junos Tanaka), mochiyu (C. inflata Hort. ex Tanaka), and ponkan (C. reticulata Blanco cv. F-2426) inhibited the formation of NDMA much more effectively than other citrus oils. The inhibitory proportions of components of citrus essential oils such as myrcene, alpha-terpinene, and terpinolene were as high as 80%.  相似文献   

Immunolocalization of ghrelin in the stomach of Sprague-Dawley rat     

Li J  Yi SQ  Wang HX  Yi N  Ogawa Y  Ozaki N  Itoh M 《Anatomia, histologia, embryologia》2011,40(2):95-99

To investigate the distribution of ghrelin in different regions of stomach in Sprague-Dawley rat, and attempt to compare with those of humans and other mammalian species in this study, the stomach of rats was divided into five sections, cardia, fundus, greater curvature, lesser curvature and pylorus. Immunohistochemistry and Western blotting were performed to investigate the ghrelin-producing cells. The immunolocalization and protein levels of ghrelin differed significantly in different regions of stomach in rats. It was present at a high level in the greater curvature of the pars glandularis, and the lesser curvature. In the fundus and pylorus, no ghrelin immunoreactive cells were detected. In this study, we elucidated the distribution of ghrelin-producing cells in different regions of rat stomach in detail for the first time. It is further considered that the differences of ghrelin distribution in stomach of different species may induce different stimulatory effects on fat accumulation and metabolism.  相似文献   

Natural 15N and 13C abundance in Andisols influenced by long-term fertilization management in Japan     

Bingzi Zhao  Morihiro Maeda  Yasuo Ozaki 《Soil Science and Plant Nutrition》2013,59(4):555-562

Two field experiments were conducted on Andisols in Japan to evaluate the changes in the natural ¹⁵N and ¹³C abundance in the soil profile and to determine whether the values of δ¹⁵N could be used as an indicator of fertilizer sources or fertilizer fate. The 6-year experiment conducted at the National Agricultural Research Center (NARC) consisted of the following treatments: application of swine compost (COMPOST), slow-release nitrogen fertilizer (SRNF), readily available nitrogen fertilizer (RANF), and absence of fertilization (CONTROL). Experimental plots located at the Nippon Agricultural Research Institute (NARI) received cattle compost at different rates for 12 years; a forest soil at this site was sampled for comparison. Swine compost application led to a considerable change in the δ¹⁵N distribution pattern in the soil profile, with the highest δ¹⁵N values recorded in the top 20 cm layers of the COMPOST plot, decreasing in the sequence of CONTROL >- RANF > SRNF, mainly due to the relatively high δ¹⁵N value of swine compost and its subsequent decomposition. In contrast, SRNF application resulted in the lowest δ¹⁵N values in soil, indicating the presence of negligible nitrogen losses relative to input and low nitrogen cycling rates. Values of δ¹⁵N increased with compost application rates at NARI. In the leachate collected at 1-m depth, the δ¹⁵N values decreased in the sequence of COMPOST > RANF ≥ CONTROL > SRNF. The δ¹³C values in soil peaked in the 40–60 cm layers for all the fertilizers. The δ¹³C value was lowest in forest soil due to the presence of plant residues in soil organic matter. These results indicated that the δ¹⁵N values in the upper soil layers or leachate may enable to detect pollution sources of organic or inorganic nitrogen qualitatively in Andisols.  相似文献   

Comparison of useful terrestrial and aquatic plant species for removal of nitrogen and phosphorus from domestic wastewater     

Kaoru Abe  Yasuo Ozaki 《Soil Science and Plant Nutrition》2013,59(4):599-607

To develop a low cost and energy-saving wastewater treatment technique in combination with resource recycling and amenity functions, we constructed a plant bed filter ditch in which useful terrestrial and aquatic plants can be utilized for nitrogen and phosphorus removal from wastewater. Screening studies were conducted to evaluate and compare the effectiveness of 20 kinds of plant species which are economically important or exhibit on aesthetic value, including 13 terrestrial species, for domestic wastewater treatment. Artificial wastewater containing 20 mg L^-1 of Nand 3.3 mg L^-1 of P, was supplied to the ditch at the rate of about 1.41–2.08 g m^-2 d^-1 for N and 0.20–0.33 g m^-2 d^-1 for P. The experiments were performed in a glass house with windows opened from April to November. The ditches showing high Nand P removal rates were planted with plants which exhibited high biomass production rates. In the case of the papyrus ditch, Nand P removal rates exceeded 0.8 g m^-2 d^-1 for N and 0.15 g m^-2 d^-1 for P from late spring to autumn, in the case of the kenaf ditch and sorghum ditch, from summer to autumn and in the case of the Italian ryegrass ditch and barley ditch, in early spring. These findings indicated that efficient wastewater treatment can be performed consistently except in the winter season, by cultivating these plants in an appropriate combination in the ditches.  相似文献   

The characterization of low pathogenic avian influenza viruses isolated from wild birds in northern Vietnam from 2006 to 2009     

Hiroki Takakuwa  Tetsu Yamashiro  Mai Q. Le  Lien S. Phuong  Hiroichi Ozaki  Ryota Tsunekuni  Tatsufumi Usui  Hiroshi Ito  Tsuyoshi Yamaguchi  Toshihiro Ito  Toshiyuki Murase  Etsuro Ono  Koichi Otsuki 《Comparative immunology, microbiology and infectious diseases》2013

Due to concerns that wild birds could possibly spread H5N1 viruses, surveillance was conducted to monitor the types of avian influenza viruses circulating among the wild birds migrating to or inhabiting in northern Vietnam from 2006 to 2009. An H5N2 virus isolated from a Eurasian woodcock had a close phylogenetic relationship to H5 viruses recently isolated in South Korea and Japan, suggesting that H5N2 has been shared between Vietnam, South Korea, and Japan. An H9N2 virus isolated from a Chinese Hwamei was closely related to two H9N2 viruses that were isolated from humans in Hong Kong in 2009, suggesting that an H9N2 strain relevant to the human isolates had been transmitted to and maintained among the wild bird population in Vietnam and South China. The results support the idea that wild bird species play a significant role in the spread and maintenance of avian influenza and that this also occurs in Vietnam.  相似文献   

Behavioral and electrophysiological investigation on taste response of the termite Zootermopsis nevadensis to wood extractives     

Wakako Ohmura  Mamiko Ozaki  Ryohei Yamaoka 《Journal of Wood Science》2006,52(3):261-264

Termite feeding behavior and the chemoreception of plant extracts were evaluated to investigate the water extracts from akamatsu (Pinus densiflora), neem (Azadirachta indica), and their equivalent mixture using pseudoergates of Zootermopsis nevadensis. In behavioral assays, termite preference was akamatsu > akamatsu plus neem > neem. Electrophysiological recordings from the taste hairs on labial palps showed vigorous impulse discharge to akamatsu extract but much lower response to neem extract. The response to akamatsu plus neem was mostly the same as that to neem alone, suggesting the neem extracts inhibited the responses to akamatsu extracts. In the present article, we discuss the correlations between the feeding behaviors and the responses at their taste cells to these different extracts.  相似文献   

Discovery of single-nucleotide mutations in acetolactate synthase genes by Ecotilling     

Guang-Xi Wang  Mui-Keng Tan  Hiromasa Saitoh  Toshiyuki Imaizumi  Tohru Tominaga 《Pesticide biochemistry and physiology》2007,88(2):143-148

TILLING (Targeting Induced Local Lesions IN Genomes) is a powerful reverse genetic technique that employs a mismatch-specific endonuclease to discover induced point mutations in genes of interest. The use of the TILLING technique to survey natural variation in genes is called Ecotilling. We report an adaptation of Ecotilling for rapid detection of single-nucleotide mutations in the acetolactate synthase (ALS) genes of sulfonylurea (SU)-resistant (R) Monochoria vaginalis (Pontederiaceae), a paddy weed, in Japan. Genomic DNA of a SU-R plant (target DNA) was mixed with the DNA of a SU-susceptible (S) plant (reference DNA). Ecotilling detected two nucleotide mutations in the ALS gene of SU-R M. vaginalis. These 2 mutations were confirmed by DNA sequencing. A single nucleotide mutation (C to A), in the codon CCT to CAT and another mutation (C to T), in the codon CCT to TCT were identified by sequencing. Both mutations result in the disruption of a Pro codon in the conserved Domain A region with the consequent substitution of a His residue in the first mutation and a Ser residue in the second. Substitution of the Pro residue in Domain A of the ALS gene has been reported to result in insensitivity to SUs in many weed biotypes. This study demonstrates that Ecotilling is a fast, reliable, economical method for detecting single-nucleotide mutations in genes arising from herbicide selection.  相似文献   

Identification of a novel gene (Apq1) from the indica rice cultivar ‘Habataki’ that improves the quality of grains produced under high temperature stress     

Kazumasa Murata  Yukihide Iyama  Takuya Yamaguchi  Hidenobu Ozaki  Yoshinori Kidani  Takeshi Ebitani 《Breeding Science》2014,64(4):273-281

The appearance of brown rice grown under high temperature conditions is an important characteristic for improvement in Japanese rice breeding programs. We performed a QTL analysis of the appearance quality of brown rice using chromosome segment substitution lines of the indica cultivar ‘Habataki’ in the ‘Koshihikari’ genetic background. A line carrying a ‘Habataki’ segment on chromosome 7 showed a high percentage of perfect grains produced under high temperature conditions during the ripening period. To verify the role of this segment, and to narrow down the region containing the useful allele, substitution mapping was performed using multiple paired lines. As a result, the chromosomal location of a gene that we named Appearance quality of brown rice 1 (Apq1) was delimited to a 48-kb region. In addition, we developed an Apq1-near isogenic line (NIL) to evaluate the effect of Apq1 on various agronomic traits. Under high temperature conditions during the ripening period, the Apq1-NIL produced significantly higher percentages of perfect grains than ‘Koshihikari’. Other agronomic traits, including yield and palatability, were similar between the Apq1-NIL and ‘Koshihikari’. Therefore, the ‘Habataki’ allele of Apq1 will be useful in breeding programs aimed at improving the quality of grains ripened under high temperature conditions.  相似文献