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991.
We explored the use of ecological niche-modeling from data compiled in a participatory program of thousands of volunteer observers to quantitatively evaluate the spatial risk of invasion by the alien species Bombus terrestris. B. terrestris has been commercially introduced to Japan for the pollination of greenhouse tomato crops since 1991. Recently, naturalized populations of this species have spread rapidly, particularly in Hokkaido, northern Japan. Two niche-based models were constructed from independent data sets (presence-absence and presence-only data sets) and were used to validate one another. Both models performed well and indicated that the data compiled by participatory programs were useful for generating predictive models of the potential distribution of this invasive species. The models also revealed that the potential distribution of B. terrestris is negatively related to the proportion of woodland area, which corresponds to the known biology of this species. In contrast, the effect of the number of colonies introduced for tomato pollination (represented by tomato production) did not significantly affect the distribution of B. terrestris, indicating that its spread is now entering a phase of dispersal from established feral populations and that primary dispersal from commercial colonies in greenhouses is no longer a limiting factor for the distribution of this invasive species. 相似文献
992.
Kentaro Ikeda Shinpei Banno Ken Watanabe Masashi Fujinaga Hideki Ogiso Hiroshi Sakai Hitoshi Tanaka Shizue Miki Satoshi Shibata Toshimasa Shiraishi Makoto Fujimura 《Journal of General Plant Pathology》2012,78(5):331-337
Chinese cabbage yellows caused by Verticillium dahliae and V. longisporum is one of the most economically important diseases in Japan. Verticillium isolates from infected Chinese cabbage in Japan were identified as V. dahliae and V. longisporum based on morphological characteristics and newly developed molecular genotyping methods using group I intron of 18S rDNA, mitochondrial-SSU rDNA and cob gene. Although the two species were equally virulent to Chinese cabbage in the greenhouse, V. longisporum was more virulent in the field compared with V. dahliae. Among the 67 Verticillium isolates from Chinese cabbage, 53 were V. longisporum and considered to be the major pathogen. The isolation frequency of V. longisporum was 98?% in Ibaraki and eastern Gunma where Chinese cabbage was cropped from autumn to winter. In contrast, the frequency was 48?% in Nagano and north to west Gunma where the plant was cropped in cool summer and highland conditions and the rests were V. dahliae. This is the first report to show the different geographical distribution of V. longisporum and V. dahliae in Chinese cabbage production area of Japan. 相似文献
993.
Kato A Obara K Igarashi T Tsuruoka H Nakagawa S Hirata N 《Science (New York, N.Y.)》2012,335(6069):705-708
Many large earthquakes are preceded by one or more foreshocks, but it is unclear how these foreshocks relate to the nucleation process of the mainshock. On the basis of an earthquake catalog created using a waveform correlation technique, we identified two distinct sequences of foreshocks migrating at rates of 2 to 10 kilometers per day along the trench axis toward the epicenter of the 2011 moment magnitude (M(w)) 9.0 Tohoku-Oki earthquake in Japan. The time history of quasi-static slip along the plate interface, based on small repeating earthquakes that were part of the migrating seismicity, suggests that two sequences involved slow-slip transients propagating toward the initial rupture point. The second sequence, which involved large slip rates, may have caused substantial stress loading, prompting the unstable dynamic rupture of the mainshock. 相似文献
994.
Baba K Itamoto K Amimoto A Kitagawa K Hiraoka H Mizuno T Sato H Okuda M 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2012,74(6):775-778
Two dogs, emigrated from Zambia and China to Japan, were diagnosed with Ehrlichia canis infection. Both cases had thrombocytopenia, non-regenerative anemia, and hypergloblinemia with polyclonal gammopathy. Case 1 had ataxia of the hind limbs. Severe meningitis was revealed by magnetic resonance imaging examination. Intracytoplasmic inclusions were observed in mononuclear cells of cerebrospinal fluid. Case 2 had a history of bilateral epistaxis, and severe pancytopenia was noticed in complete blood count. Diagnosis was finally achieved by nested polymerase chain reaction and sequence analysis. Thus, even in non-endemic areas, E. canis infection should be included in the differential diagnosis of clinically ill dogs that emigrated from endemic areas. 相似文献
995.
Nakamura Y Usui F Miyahara D Mori T Ono T Kagami H Takeda K Nirasawa K Tagami T 《The Journal of reproduction and development》2012,58(4):432-437
Primordial germ cells (PGCs) are embryonic precursors of germline cells with potential applications in genetic conservation, transgenic animal production and germline stem cell research. These lines of research would benefit from improved germline transmission of transplanted PGCs in chimeric chickens. We therefore evaluated the effects of pretransplant X-irradiation of recipient embryos on the efficacy of germline transmission of donor PGCs in chimeric chickens. Intact chicken eggs were exposed to X-ray doses of 3, 6 and 9 Gy (dose rate = 0.12 Gy/min) after 52 h of incubation. There was no significant difference in hatching rate between the 3-Gy-irradiated group and the nonirradiated control group (40.0 vs. 69.6%), but the hatching rate in the 6-Gy-irradiated group (28.6%) was significantly lower than in the control group (P<0.05). No embryos irradiated with 9 Gy of X-rays survived to hatching. X-irradiation significantly reduced the number of endogenous PGCs in the embryonic gonads at stage 27 in a dose-dependent manner compared with nonirradiated controls. The numbers of endogenous PGCs in the 3-, 6- and 9-Gy-irradiated groups were 21.0, 9.6 and 4.6% of the nonirradiated control numbers, respectively. Sets of 100 donor PGCs were subsequently transferred intravascularly into embryos irradiated with 3 Gy X-rays and nonirradiated control embryos. Genetic cross-test analysis revealed that the germline transmission rate in the 3-Gy-irradiated group was significantly higher than in the control group (27.5 vs. 5.6%; P<0.05). In conclusion, X-irradiation reduced the number of endogenous PGCs and increased the germline transmission of transferred PGCs in chimeric chickens. 相似文献
996.
Haraguchi T Tani K Takagishi R Oda Y Itamoto K Yamamoto N Terai S Sakaida I Nakazawa H Taura Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2012,74(5):607-611
Regenerative medicine using bone marrow cells is an attractive therapy for the cure of patients with severe liver disease. Here, we show the therapeutic potential of canine bone marrow stromal cells (BMSCs) in mouse models of CCl(4)-induced chronic liver dysfunction. We used two different models for xenotransplantation, nude mice and cyclosporine A (CSA) immunosuppressed mice. Serum parameters from a standard liver panel were not improved following transplantation. However, fibrotic liver lesions with severe inflammation were decreased in CCl(4)-treated CSA mice following BMSC transplantation. Effective migration of transplanted canine BMSCs was limited to persistently injured liver in CCl(4)-treated CSA mice, where they may be effective in resolving inflammatory fibrotic lesions. These results suggest that canine BMSCs are an effective cell source for liver regeneration. 相似文献
997.
Ishihara K Hosokawa Y Makita K Noda J Ueno H Muramatsu Y Ueno H Mukai T Yamamoto H Ito M Tamura Y 《Research in veterinary science》2012,93(2):574-580
Factors associated with the carriage of antimicrobial-resistant Escherichia coli isolates were analysed among zoo animals. An association was observed between selection of amoxicillin as the first-line therapy and a significantly higher percentage of resistance to ampicillin (54.5%) from 11 animals treated with antimicrobials, compared with isolates from 32 untreated animals (9.4%). In addition, the percentage resistance to kanamycin (36.4%), gentamicin (27.3%), trimethoprim (27.3%) and tetracycline (63.6%) from 11 treated animals was significantly higher than those from 32 untreated animals (3.1%, 3.1%, 3.1% and 25%, respectively), although these antimicrobials were rarely used. All kanamycin-, gentamicin- and trimethoprim-resistant isolates and more than half of the tetracycline-resistant isolates from treated animals were also resistant to ampicillin. Co-resistance to other antimicrobials with ampicillin was suggested to contribute to an increasing of resistance towards antimicrobials that were rarely administered. The present investigation revealed an association of antimicrobial treatment with the spread of antimicrobial-resistant bacteria among zoo animals. 相似文献
998.
Kameo Y Nagao Y Nishio Y Shimoda H Nakano H Suzuki K Une Y Sato H Shimojima M Maeda K 《Veterinary microbiology》2012,154(3-4):222-229
In the spring of 2007, seven raccoon dogs and a weasel were captured near the city of Tanabe in Wakayama prefecture, Japan. The causative agent of the animals' death 1-2 days after capture was identified as canine distemper virus (CDV) by virus isolation, immunostaining with an anti-CDV polyclonal antibody, and a commercially available CDV antigen-detection kit. Sequence analysis of hemagglutinin genes indicated the isolated viruses belong to genotype Asia-1 and possess the substitution from tyrosine (Y) to histidine (H) at position 549 that is associated with the spread of CDV to non-canine hosts. A serosurvey for CDV was then conducted among wild animals in the region. The animals assayed consisted of 104 raccoons, 41 wild boars, 19 raccoon dogs, five Sika deer, two badgers, one weasel, one marten, one Siberian weasel and one fox. Virus-neutralization (VN) tests showed that, except for fox and weasel, all of the species assayed had VN antibodies to CDV. Interestingly, 11 of the 41 wild boars (27%) and two of the five Sika deer assayed possessed VN antibodies to CDV. These findings indicate that CDV infection was widespread among wild mammals during this epizootic. 相似文献
999.
We performed a neuroblastoma cell (Neuro2a) culture assay modified slightly from a method reported previously to provide a simple and sensitive evaluation of paralytic shellfish poisoning (PSP) toxicity in shellfish. The cell bioassay was just as sensitive for C-toxins as for gonyautoxins. The sensitivity of our cell bioassay was 4 times that of the current standard mouse bioassay. Using the cell bioassay, we evaluated PSP toxicity in 361 shellfish samples collected from Mikawa Bay and Ise Bay, Aichi Prefecture, Japan, from April 1999-March 2002. The results were compared with those obtained in a postcolumn derivatization liquid chromatographic analysis. PSP toxins were detected in 236/361 samples by both assays, and there was a fairly good correlation (r = 0.9001, n = 236, p < 0.001) between the results from the two assays. We applied this cell bioassay when short-necked clams in the bay turned poisonous in 2001. The chronological changes in PSP toxicity in the short-necked clams were analyzed and compared with those of the cell density of poisonous plankton (Alexandrium tamarense) occurring in the bay. The PSP toxicity in shellfish peaked 2 weeks after the cell density reached a maximum. We recommend using the cell bioassay for routine monitoring of PSP toxicity in shellfish living in natural marine environments. 相似文献
1000.
Hiroshi Saotome Hideaki Korai Takahiko Iida Tomoko Hamano Kensuke Kawarada Masaharu Ohmi 《Journal of Wood Science》2012,58(5):423-428
An air-injection press (AIP) was developed to prevent accidental blowouts of boards during production. In this study, the effects of the AIP on preventing blowouts were investigated by artificially creating a blowout-prone condition, and the press was shown to be effective in preventing blowouts. The modulus of rupture of the boards was almost constant irrespective of pressing time. Longer pressing time resulted in higher internal bond strength when pressed at 170 °C. The thickness swelling of the boards pressed at 170 or 190 °C was almost uniform irrespective of pressing time, and the manufactured boards showed performance similar to those manufactured with an ordinary press. The AIP prevented blowouts sufficiently even when the pressure of the injected air was reduced, and this reduction did not adversely decrease the performance of the boards. Air injection reduced formaldehyde emissions from the board. 相似文献