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Sugawara M Komori J Kawakami M Izumiya H Watanabe H Akiba M 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(3):345-349
Isolates of extended-spectrum cephalosporin (ESC)-resistant Salmonella enterica serovar Typhimurium obtained from two different farms in Fukushima Prefecture, Japan, in 2007 were characterized in order to determine the genetic basis of resistance. ESC resistance in the two isolates was mediated by an AmpC β-lactamase encoded by the bla(CMY-2) gene, which is located in a large self-transmissible plasmid in each isolate. The sizes of the bla(CMY-2)-carrying plasmids were different. The replicon types of the plasmids were I1-Iγ and A/C. The results of macrorestriction analysis and phage typing suggest a close relationship between both isolates. This is the first report of ESC-resistant S. Typhimurium isolated from cattle in Japan. 相似文献
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Tetsuo Asai Kaori Masani Chizuru Sato Mototaka Hiki Masaru Usui Kotaro Baba Manao Ozawa Kazuki Harada Hiroshi Aoki Takuo Sawada 《Acta veterinaria Scandinavica》2011,53(1):52
A total of 318 Escherichia coli isolates obtained from different food-producing animals affected with colibacillosis between 2001 and 2006 were subjected to phylogenetic analysis: 72 bovine isolates, 89 poultry isolates and 157 porcine isolates. Overall, the phylogenetic group A was predominant in isolates from cattle (36/72, 50%) and pigs (101/157, 64.3%) whereas groups A (44/89, 49.4%) and D (40/89, 44.9%) were predominant in isolates from poultry. In addition, group B2 was not found among diseased food-producing animals except for a poultry isolate. Thus, the phylogenetic group distribution of E. coli from diseased animals was different by animal species. Among the 318 isolates, cefazolin resistance (minimum inhibitory concentrations: ≥32 μg/ml) was found in six bovine isolates, 29 poultry isolates and three porcine isolates. Of them, 11 isolates (nine from poultry and two from cattle) produced extended spectrum β-lactamase (ESBL). The two bovine isolates produced blaCTX-M-2, while the nine poultry isolates produced blaCTX-M-25 (4), blaSHV-2 (3), blaCTX-M-15 (1) and blaCTX-M-2 (1). Thus, our results showed that several types of ESBL were identified and three types of β-lactamase (SHV-2, CTX-M-25 and CTX-M-15) were observed for the first time in E. coli from diseased animals in Japan. 相似文献
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Umeki S Suzuki R Shimojima M Ema Y Yanase T Iwata H Okuda M Mizuno T 《Veterinary immunology and immunopathology》2011,142(1-2):119-125
Thirteen different monoclonal antibodies against canine P-selectin glycoprotein ligand-1 (cPSGL-1) were obtained by immunization of rats with cells of a canine lymphoma cell line (Ema). O-sialoglycoprotein endopeptidase treatment of Ema cells showed that all of these antibodies recognized O-glycosylated peptides of canine PSGL-1. Experiments using deletion or point mutants of cPSGL-1 indicated that these antibodies could be categorized into several groups based on their cPSGL-1 recognition characteristics. These anti-cPSGL-1 monoclonal antibodies will be useful for analysis of the canine P-selectin and PSGL-1 system. 相似文献
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Ebenezer Annan-Afful Noriko Iwashima Ernest Otoo Kwame Osafredu Asubonteng Daisuke Kubota Akira Kamidohzono 《Soil Science and Plant Nutrition》2013,59(5):649-664
The bulk density and nutrient distribution in soil profiles as affected by various land use systems were studied. Mean bulk densities of the various soil profiles, 0-20, 20-40, and 4060 cm in the selected five land use systems along the upland / lowland topo-sequences were, 1.26, 1.73, and 1.44 Mg m-3 for the primary forest (PF) plot in the upland area, 1.13, 1.51, and 1.50 Mg m-3 for the cacao farm (CP) plot, 1.16, 1.63, and 1.26 Mg m-3 for the mixed cropping (MC) plot, 1.39, 1.61, and 1.50 Mg m-a for the fallow (Fallow) plot, all three land use systems being in the upland / fringe areas, and 1.46, 1.72, and 1.60 Mg m-3 for the lowland traditional rice farming (TR) plot, respectively. The very high bulk density of the second layer, especially in the PF plot, may be related to the hardening of the iron / quartz stone layer due to prolonged dry conditions, which may affect plant growth and hydrological cycles in the benchmark inland valley watersheds. The TC contents of the topsoil samples were 43, 32, 24, 26, 18, and 15 g kgm-1 for the PF, CP, Fallow, MC, TR, and sawah (Sawah) plots, respectively. The C / N ratios of the topsoil samples were 10, 10, 9.8, 9.1, 8.8, and 8.8 for the CP, Fallow, MC, Sawah, TR, and PF plots, respectively, displaying a higher natural fertility, especially for the N supply in the PF plot in the upland area. The available phosphorus levels were low even for the topsoil samples, 1.8 to 3.4 mg kg-1 for the upland soils while the lowland TR and Sawah plots recorded values of 4.4 and 4.9 mg kg-1, respectively. The contents of exchangeable K, 0.1-0.4 cmole kg-1, of the topsoil samples were in the range of those of normal inland valley soils in West Africa. In contrast to the content of available P, although the MC plot showed a depletion, the PF, Fallow, and CP plots showed a replenishment of available K through biological nutrient cycling. The levels of exchangeable Ca and Mg as well as eCEC, were also relatively high compared to those of mean inland valley soils in West Africa. The major component of eCEC was Ex. Ca. The levels of Ex. Ca in the topsoil samples were 11.1, 9.1, 7.8, 4.7, 5.1, and 3.9 cmolc kg-1 for the PF, CP, Fallow, MC, TR, and Sawah plots, respectively. The distinctive feature of Ex. Mg was its large distribution in the upper soil profiles in the CP plot, indicating that in the cacao farms, Ex. Mg was enriched, probably due to the high level of Mg in the leaf litter. The lowland soils, normally, should have been enriched in exchangeable bases such as Ca, K, and Mg, leading to a higher eCEC value and higher general fertility through the process of geological fertilization, Le., nutrient flows from upland to lowland areas, as in the case of lowland sawah in monsoon Asia. At the benchmark sites, however, the effects of the geological fertilization process were not evident. This is one of the most important characteristics of West African inland valley watersheds. 相似文献
77.
A new cytotoxic 25-membered macrolide, amphidinolide C2 (1), has been isolated from marine dinoflagellate Amphidinium sp. (Y-71 strain), and the structure 1 was elucidated on the basis of spectroscopic data and chemical means. 相似文献
78.
Ground-dwelling beetle community in beech forests of Sado Island,Japan: comparison with the mainland
Island ecosystems differ from mainland ecosystems in their long-term isolation. On Sado Island, Japan, cattle grazing in the
past gradually changed forests into grasslands, thereby altering the diversity of indigenous insects. We compared ground-dwelling
beetle diversity on Sado Island to that on the nearby mainland. Contrary to previous reports, the island isolation effect
resulted in lower γ and β diversity than on the mainland, because of the low species richness of beetles with low dispersal
abilities. Few flightless beetles could invade Sado Island, even when the beech forests on the island were relatively adjacent
to those on the mainland. Such a history of ecosystem formation could be the general pattern for continental-island mountain
forests that were never connected to those of the mainland. We did not observe low α diversity of ground-dwelling beetles,
suggesting that the cattle grazing history of the island has not changed environmental conditions for ground-dwelling beetles
enough to reduce their diversity. In addition, cattle grazing increases the abundance of merdivorous insects by increasing
the abundance of their food resource.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
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