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131.
Gillian A. Perkins Laura B. Goodman Koji Tsujimura Gerlinde R. Van de Walle Sung G. Kim Edward J. Dubovi Nikolaus Osterrieder 《Veterinary microbiology》2009,139(3-4):375-378
A single nucleotide polymorphism in the equine herpesvirus 1 (EHV-1) DNA polymerase gene (ORF30 A2254 to G) has been associated with clinical signs of equine herpes myeloencephalopathy (EHM). The purpose of our study was to determine the odds ratio for this genetic marker and EHM using a panel of field isolates from North America collected over the past twenty-three years. EHV-1 isolates cultured at the Cornell University Animal Health Diagnostic Laboratory from 1984 to 2007 were retrieved along with their clinical histories. DNA was extracted from these EHV-1 cultures and allelic discrimination was performed using real-time PCR. The results were confirmed by sequencing of the target region in ORF30. PCR and sequencing were in 100% agreement and showed that 19 out of the 176 isolates had the ORF30 G2254 allele (11%), of which16 were EHM cases and 3 respiratory or abortion cases. The odds of having neurologic disease with the ORF30 G2254 genotype were computed as 162 times greater than those with the opposite allele ORF30 A2254 (95% confidence interval: 35–742). Despite this strong statistical significance, 24% (5/21) of horses with neurologic disease in our study population harbored the “non-neurologic” form of the allele (ORF30 A2254), suggesting that other factors may also contribute to the onset of EHM. 相似文献
132.
Koiwai M Hamaoka T Haritani M Shimizu S Zeniya Y Eto M Yokoyama R Tsutsui T Kimura K Yamane I 《Veterinary parasitology》2006,135(2):175-179
Serum samples from 2420 clinically healthy dairy cattle, randomly selected from stored sera in 18 districts of Japan, were tested for the presence of Neospora caninum antibodies using an indirect fluorescent antibody test (titer > or =1:200). Nationwide seroprevalence is estimated at 5.7% (139/2420). Seropositive cattle were detected in all surveyed districts despite the evidence of confirmed case reports of bovine neosporosis, showing that N. caninum is widely distributed throughout Japan. Age-specific seroprevalence did not increase with cattle age, suggesting that Neospora infection is likely to be transmitted vertically rather than horizontally in Japan. Considering that N. caninum seropositive cows are thought to be more likely to abort, substantial fetal losses may be induced by N. caninum infection in Japan. Devising strategies are needed to reduce the economic impact on the Japanese dairy industry. This is the first study to investigate the nationwide seroprevalence of N. caninum in cattle in Asia. 相似文献
133.
Koji Murashita Hirofumi Furuita Hiroyuki Matsunari Takeshi Yamamoto Masahiko Awaji Kazuharu Nomura Jiro Nagao Hideki Tanaka 《Fish physiology and biochemistry》2013,39(4):895-905
The pancreatic digestive enzymes, trypsin, chymotrypsin, lipase and amylase were partially characterized, and changes in their activities were examined during the initial ontogeny of Japanese eel Anguilla japonica larvae from 5 to 34 days post-hatching (dph). The pH optima of the eel larval enzymes were narrower than those other fish species; trypsin activity was highest at pH 9, chymotrypsin and amylase activities were highest at pH 7 and 8, and lipase activity was highest at pH 8 and 9. In an analysis of thermal profiles, the larval pancreatic enzymes had a high optimal temperature and high thermal stability, which are typical of fish from the tropics. At 12 and 13 dph, lipase activity and gene expression levels of trypsin (-a and -b), lipase and amylase decreased markedly, suggesting a marked change in larval metabolism at that time. These data could be useful in the development of artificial larval diets in Japanese eel. 相似文献
134.
Hiroko Sasaki Hiroto Murase Hiroshi Kiwada Koji Matsuoka Yoko Mitani Sei‐ichi Saitoh 《Fisheries Oceanography》2013,22(6):496-508
Two closely related baleen whale species, sei and Bryde's whales, in the western North Pacific were studied to identify differences in habitat use. Data were obtained from May to August 2004 and 2005. This study examined the relationship between oceanographic features derived from satellite data and the distribution of sei and Bryde's whales using basic statistics. We investigated oceanographic features including sea surface temperature (SST), sea surface chlorophyll a (Chl‐a), sea surface height anomalies (SSHAs), and depth of the habitat. These two whale species used habitats with different SST, Chl‐a, and SSHA ranges. The 0.25 mg m?3 Chl‐a contour (similar to the definition of the Transition Zone Chlorophyll Front) was a good indicator that separated the habitats of sei and Bryde's whales. Then generalized linear models were used to model the probabilities that the whale species would be present in a habitat and to estimate their habitat distribution throughout the study area as a function of environmental variables. The potential habitats of the two species were clearly divided, and the boundary moved north with seasonal progression. The habitat partitioning results indicated that SST contributed to the patterns of habitat‐use and might reflect differences in prey species between the two whales. This study showed that the habitats of the sei and Bryde's whales were clearly divided and their potential habitat‐use changed seasonally. 相似文献
135.
Hiroto Murase Toshihide Kitakado Takashi Hakamada Koji Matsuoka Shigetoshi Nishiwaki Mikio Naganobu 《Fisheries Oceanography》2013,22(3):154-173
The spatial distribution of Antarctic minke whales in the Ross Sea with relation to spatial distributions of their prey – krill – was investigated in this study using generalized additive models (GAMs). Spatial distributions of two species of krill (ice and Antarctic krill) were estimated by GAMs. Three abiotic factors – distance from the continental shelf break (800 m isobaths), the mean temperature and salinity from the surface to 200 m (MTEM‐200 and MSAL‐200), and latitude and longitude – were used as covariates for models of krill. Estimated spatial distributions of krill were then used with other covariates to model the spatial distribution of Antarctic minke whales. In the selected model of Antarctic minke whales, Antarctic krill were more influential than ice krill. The number of Antarctic minke whales increased as the density of Antarctic krill increased to around 1.5 g m?2. Beyond that, the number of Antarctic minke whales decreased as the density of Antarctic krill increased. High densities of the Antarctic minke whales were estimated along the sea ice edge in the eastern part of the Ross Sea. Specifically, the densities were high in the north of the continental shelf break where low MTEM‐200 and MSAL‐200 and intermediate densities of Antarctic krill were observed. Further data collection is needed to investigate interannual variations and trends in their relationship. The results show that the spatial distribution of Antarctic minke whales is a function of longitude, distance from the shelf break, oceanographic condition (temperature and salinity), and densities of ice and Antarctic krill. 相似文献
136.
Hideki Watanabe Koji Kageyama Yoshihiro Taguchi Hayato Horinouchi Mitsuro Hyakumachi 《Journal of General Plant Pathology》2008,74(6):417-424
Pythium helicoides, P. aphanidermatum and P. myriotylum are important pathogens that cause root rot of several crops in hydroponic culture and in ebb-and-flow irrigation systems.
These species belong to a group of Pythium species that can grow at temperatures higher than 40°C. We developed a method for baiting these high-temperature Pythium species and evaluated its practicality to monitor their presence in nutrient solutions. Seeds of cucumber, tomato, radish,
hemp, perilla and millet and leaves of bent grass and rose were tested as baits in hydroponic systems. Hemp, perilla and radish
seeds and bent grass and rose leaves were more effective than the other baits for Pythium zoospores, and bent grass leaves were the most effective. In a sensitivity test, bent grass leaf traps (BLTs) detected three
Pythium species after only a 1 day exposure to suspensions of 40 zoospores per liter of water, and the frequency of detection increased
with zoospore density and with baiting period. A temperature of 38°C was optimum for the selective reisolation of the high-temperature
Pythium species from the BLTs. The BLT was also tested with inoculated and noninoculated miniature roses that shared a recirculating
nutrient solution. The pathogen was detected in the nutrient solution 23 days before the disease spread to the noninoculated
roses. In addition, P. helicoides was detected 30 days before the disease was evident in a commercial greenhouse. The baiting method described here will be
useful for monitoring high-temperature Pythium species in recirculating hydroponic culture systems. 相似文献
137.
<Emphasis Type="Italic">Turnip yellow mosaic virus</Emphasis> isolated from Chinese cabbage in Japan
Namiko Kirino Koji Inoue Koji Tanina Yuya Yamazaki Satoshi T. Ohki 《Journal of General Plant Pathology》2008,74(4):331-334
A virus that caused a distinct yellow mosaic was isolated in Okayama, Japan from Chinese cabbage (Brassica rapa L., Pekinensis group). The virus, with spherical particles ca. 28 nm in diameter, was mechanically transmissible only to
cruciferous species. From the host range, characteristic morphology of virus particles, serology and sequence analysis of
coat protein gene, the causal virus was identified as Turnip yellow mosaic virus (TYMV). Seed transmission of TYMV at 0–2.2% in Chinese cabbage was confirmed. This report is the first of TYMV from Chinese
cabbage and in Japan.
The nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases as accessions AB358971 and AB358972. 相似文献
138.
Hironori Koga Koji Dohi Reiko Yoshimoto Masashi Mori 《Journal of General Plant Pathology》2008,74(3):246-249
Resistance in the leaf blades of rice plants against a virulent race of the rice blast fungus Magnaporthe oryzae was quantitatively examined using a modified spot inoculation method. Numbers of conidia produced in the lesions were affected
by plant age and paralleled the frequency of resistance infection types, which is indicative of whole-plant-specific resistance
(WPSR), in the inoculated leaf sheaths of the corresponding plants. Exogenous abscisic acid treatment, which suppresses WPSR,
also increased the susceptibility of the leaf blades. These results indicate a correlation between the resistance of the leaf
blades and the WPSR in the leaf sheaths. 相似文献
139.
Masaru Fujinoki Tomoko Koito Suguru Nemoto Mitsugu Kitada Yoko Yamaguchi Susumu Hyodo Hideki Numanami Nobuyuki Miyazaki Koji Inoue 《Fisheries Science》2012,78(1):139-146
Various invertebrates inhabiting hydrothermal vents harbor thiotrophic endosymbionts that provide the host with nutrients
and are possibly involved in the detoxification of harmful sulfides. In this study, we first determined the partial 16S rRNA
gene sequence of the thiotrophic symbiont of the deep-sea mussel Bathymodiolus septemdierum, a dominant species at hydrothermal vents in the Izu–Ogasawara (Bonin) area. We then designed a new probe, Bsob692, for fluorescent in situ hybridization (FISH) using regions completely conserved among thiotrophic symbionts of all
bathymodiolin mussels and established the protocol for FISH to compare the distribution and amount of the symbiont using an
image analysis program that is commercially available. We compared fluorescent intensity in the gill of the mussels collected
at different sites and found a higher intensity in specimens collected from a site with higher sulfide concentration. We also
compared mussels reared in the presence and absence of sulfide and found that the former had a higher fluorescent intensity. 相似文献
140.
Fukuma Yasufumi Yamane Akihiko Itoh Tomohiro Tsukamasa Yasuyuki Ando Masashi 《Fisheries Science》2012,78(2):451-461
Fish meat was brought to a supercooled state through slow cooling, and changes in the texture, histology, and protein composition
of the meat were investigated. The groups whose storage temperature were lowered by 1.0°C per day (the 1.0°C group) and 0.5°C
per day (the 0.5°C group) began to freeze in the vicinity of −3.5 and −5.0°C, respectively. The freezing point depended on
the fish species; the lowest freezing point was −8.5°C, for the red sea bream in the 1.0°C group. The breaking strength tended
to decrease more slowly in the 1.0°C group, but the collagen fibers collapsed more rapidly in the 1.0°C group. In SDS electrophoresis,
a slight change in the banding patterns was observed, but the relationship between this observation and changes in histology
and physical properties was unclear. This study shows that it is possible to produce a supercooled state in fish meat, and
demonstrates that supercooling is a potential new storage method that lowers the temperature without generating ice crystals. 相似文献