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941.
Watanabe S Shirasuna K Matsui M Yamamoto D Berisha B Schams D Miyamoto A 《The Journal of reproduction and development》2006,52(4):551-559
Endothelin-1 (ET-1) is a luteolytic mediator in the bovine corpus luteum (CL), and its action appears to be via endothelin type A receptor (ETR-A). Thus, the aim of the present study was to determine the effect of ETR-A antagonist on PGF2alpha-induced luteolysis in the cow. Cows on days 10-12 of the estrous cycle were subjected to five intraluteal injections of the ETR-A antagonist LU 135252 in saline or only saline at -0.5, 2, 4, 6, and 8 h after PGF2alpha administration (=0 h). Serial luteal biopsies were conducted to determine the expression of mRNA in the luteal tissue. There were no significant differences in the decrease in plasma progesterone (P) concentrations and the mRNA expressions of steroidogenic acute regulatory protein and 3beta-hydroxysteroid dehydrogenase/Delta5, Delta4-isomerase between the ETR-A antagonist-treated group and the control group. However, the start of the decline in CL volume and blood flow area surrounding the CL was delayed for almost two days in the ETR-A antagonist-treated group compared to the control group. The mRNA expression of preproET-1 and endothelin type B receptor increased in both groups, while the ETR-A mRNA remained unchanged. In addition, caspase-3 mRNA expression increased significantly at 24 h in the control group only and its level was higher than that of the ETR-A antagonist-treated group. Thus, the present study suggests that ET-1 regulates structural luteolysis via ETR-A by controlling blood vessel contraction in the CL of the cow. 相似文献
942.
Watanabe M Oikawa T Hiraoka H Kaneko N Itamoto K Mizuno T Okuda M Inokuma H 《Veterinary parasitology》2006,136(2):147-154
Three beagle dogs were inoculated with mice spleen/liver homogenate infected with Ehrlichia species detected from Ixodes ovatus (EIO) and one dog was used as a control. All three infected dogs did not show clinical signs of disease except for mild pyrexia throughout the 41-day study period. Splenomegaly was observed from Day 7 post-inoculation (p.i.) in two of the dogs. Hematological and biochemical abnormalities included mild thrombocytopenia, hypoproteinaemia, hypoalbuminaemia and increased C-reactive protein values. One of the dogs' splenic aspirate sample was PCR-positive for Ehrlichia Day 7 p.i. and another dogs' blood and bone marrow aspirate sample was PCR-positive Day 41 p.i. Sequence analysis of the PCR products showed 100% homology with the 16SrRNA partial gene sequence of Ehrlichia sp. HF565. Antibody titers to EIO were observed in all three experimentally infected dogs starting from the first week p.i. and cross-reactivity with Ehrlichia canis was detectable in one of the dogs starting Day 7 p.i. These data suggest that infection of dogs with EIO is possible, though is probably of low pathogenic importance. Cross-reactivity of EIO infected dog serum with E. canis raises the likelihood of false E. canis seropositive dogs. 相似文献
943.
Fukui Y Yamamoto H Fujishita M Kudo N Torii K Nozawa S Takahashi K Matsumoto R Machida M Kawamura A Yonekura Y Mizuno N Onishi T Mizuno A 《Science (New York, N.Y.)》2006,314(5796):106-109
The central few hundred parsecs of the Milky Way host a massive black hole and exhibit very violent gas motion and high temperatures in molecular gas. The origin of these properties has been a mystery for the past four decades. Wide-field imaging of the (12)CO (rotational quantum number J = 1 to 0) 2.6-millimeter spectrum has revealed huge loops of dense molecular gas with strong velocity dispersions in the galactic center. We present a magnetic flotation model to explain that the formation of the loops is due to magnetic buoyancy caused by the Parker instability. The model has the potential to offer a coherent explanation for the origin of the violent motion and extensive heating of the molecular gas in the galactic center. 相似文献
944.
Corbisier P Broothaerts W Gioria S Schimmel H Burns M Baoutina A Emslie KR Furui S Kurosawa Y Holden MJ Kim HH Lee YM Kawaharasaki M Sin D Wang J 《Journal of agricultural and food chemistry》2007,55(9):3249-3257
An international CCQM-P60 pilot study involving eight national metrological institutes was organized to investigate if the quantification of genetically modified (GM) corn powder by real-time PCR was affected by the DNA extraction method applied. Four commonly used extraction methods were compared for the extraction of DNA from a GM Bt176 corn powder. The CTAB-based method yielded the highest DNA template quantity and quality. A difference in the 260 nm/230 nm absorbance ratio was observed among the different extraction methods. Real-time amplification of sequences specific for endogenous genes zein and hmg as well as transgenic sequences within the cryIA(b) gene and a fragment covering the junction between the transformed DNA and the plant genome were used to determine the GM percentage. The detection of the transgenic gene was affected by the quantity and quality of template used for the PCR reaction. The Bt176 percentages measured on diluted or purified templates were statistically different depending on the extraction method applied. 相似文献
945.
Akira Yamamoto Akira Iwata Toshiki Saito Fumiko Watanabe Susumu Ueda 《Veterinary immunology and immunopathology》2009,130(3-4):221-225
Canine granulocyte colony-stimulating factor (cG-CSF) with modification of cysteine at position 17 to serine was expressed in Brevibacillus choshinensis HPD31. cG-CSF secreted into the culture medium was purified by ammonium sulfate precipitation and consecutive column chromatography, using butyl sepharose and DEAE sepharose. Biological activity of the recombinant cG-CSF was 8.0 × 106 U/mg protein, as determined by its stimulatory effect on NFS-60 cell proliferation. Purified cG-CSF was subcutaneously administered once a day for two successive days to dogs (1, 5, 25, or 125 μg). Neutrophil count increased the following day in all dogs except those administered the lowest dose (1 μg). No severe side effects were observed in dogs after administration of cG-CSF. 相似文献
946.
Nakaoka H Gaillard C Fujinaka K Watanabe N Ito M Kawada K Ibi T Sasae Y Sasaki Y 《Journal of animal science》2009,87(1):62-71
Data from 3 prefectures and a nationwide farming corporation were used to assess the usefulness of the "link provider data" in providing indirect genetic links for the national genetic evaluation for carcass weight across weakly connected subpopulations of the Japanese Black cattle. The data from the farming corporation provided genetic links to those of all prefectures and was therefore used as the link provider data. Two national genetic evaluation strategies under an animal model were compared, based on the generalized coefficient of determination (CD) of contrasts between mean EBV of sires or maternal grandsires (MGS) from different prefectures: strategy PA-1 was a pooled analysis of the data sets of the 3 prefectures, and strategy PA-2 was a pooled analysis of the data sets of the 3 prefectures and the farming corporation. The CD of the contrasts were greater for PA-2 than for PA-1. Under PA-2, the CD of the contrasts between mean EBV of sires or MGS ranged from 0.67 to 0.78 or from 0.61 to 0.70, respectively. Pooling the data from the 3 prefectures and the farming corporation increased the degree of connectedness through the link provider data rather than the amount of information by adding more data, thus improving the accuracy of prediction. The differences between mean EBV of sires or MGS from different prefectures were smaller for PA-1 than for PA-2. This finding suggests that genetic differences in carcass weight among prefectures are present, but that they would be confused with the environmental differences under PA-1 because of the lack of genetic connectedness among the prefectures. On the other hand, the genetic differences among the prefectures would be predicted precisely under PA-2 because the genetic connectedness among the prefectures was improved by using the link provider data. The results demonstrate that the link provider data could be used to unify within-prefecture evaluation to form a Japanese national genetic evaluation across weakly connected subpopulations. 相似文献
947.
Yoshihisa OHTANI Yosuke KOBAYASHI Tatsuyuki TAKAHASHI Satoshi HAGA Mutsuo TAKAGI Takanori MASHIKO Kazuo KATOH Yoshiaki OBARA 《Animal Science Journal》2009,80(5):570-576
5'-Uridylic acid (UMP), which is present at high concentrations in cow's colostrum, has been shown to cause a reduction in increased plasma levels of insulin and glucose after ingestion of milk replacer in pre-weaning calves. However, the precise mechanisms of UMP action have not been investigated, and its action has not been investigated in other pre-weaning ruminants. In order to demonstrate whether UMP causes changes in postprandial metabolic and hormonal parameters in pre-weaning goats, 11 Saanen kids were given milk replacer (twice a day) without ( n = 5) or with ( n = 6) UMP (1 g for each meal, 2 g/day for each head) for 14 days. Analysis of blood samples taken in the morning of day 14 demonstrated that the feeding of milk replacer with UMP abolished the significant changes in postprandial plasma glucose, NEFA, GH and insulin concentrations induced by feeding of milk replacer alone, and demonstrated a tendency to increase IGF-I levels. However, there was no significant difference between the two groups at any sampling time. We conclude that UMP feeding with milk replacer showed a tendency to blunt the postprandial changes in levels of some plasma metabolites and hormones that are induced by replacer alone in pre-weaning goats. 相似文献
948.
E. L. Krick A. P. Billings F. S. Shofer S. Watanabe K. U. Sorenmo 《Veterinary and comparative oncology》2009,7(2):130-138
The purpose of this retrospective cohort study is to describe the association of cytological assessment of lymph node metastasis with survival and tumour grade in dogs with mast cell tumours. Regional lymph node aspirates of 152 dogs diagnosed with a mast cell tumour were reviewed and classified according to specific cytological criteria for staging. 97 dogs (63.8%) had stage I tumours, and 55 (36.2%) had stage II tumours. Stage II dogs had a significantly shorter survival time than dogs with stage I disease (0.8 and 6.2 years, respectively; P < 0.0001). Dogs with grade III mast cell tumours were more likely to have stage II disease (P = 0.004). These results suggest that cytological evaluation of lymph nodes in dogs with mast cell tumours provides useful and valuable clinical information, and the results correlate with tumour grade and outcome thus providing a practical and non‐invasive method for staging. 相似文献
949.
BACKGROUND: Target‐site resistance is the major cause of herbicide resistance to acetolactate synthase (ALS)‐ and acetyl‐CoA carboxylase (ACCase)‐inhibiting herbicides in arable weeds, whereas non‐target‐site resistance is rarely reported. In the Echinochloa phyllopogon biotypes resistant to these herbicides, target‐site resistance has not been reported, and non‐target‐site resistance is assumed to be the basis for resistance. To explore why target‐site resistance had not occurred, the target‐site genes for these herbicides were isolated from E. phyllopogon, and their expression levels in a resistant biotype were determined. RESULTS: Two complete ALS genes and the carboxyltransferase domain of four ACCase genes were isolated. The expression levels of ALS and ACCase genes were higher in organs containing metabolically active meristems, except for ACC4, which was not expressed in any organ. The differential expression among examined organs was more prominent for ALS2 and ACC2 and less evident for ALS1, ACC1 and ACC3. CONCLUSION: E. phyllopogon has multiple copies of the ALS and ACCase genes, and different expression patterns were observed among the copies. The existence of three active ACCase genes and the difference in their relative expression levels could influence the occurrence of target‐site resistance to ACCase inhibitors in E. phyllopogon. Copyright © 2012 Society of Chemical Industry 相似文献
950.
Tanaka Y Hosokawa M Miwa T Watanabe T Yazawa S 《Journal of agricultural and food chemistry》2010,58(22):11762-11767
Capsinoids are a group of nonpungent capsaicinoid analogues produced in Capsicum fruits. They have similar bioactivities to capsaicinoids such as suppression of fat accumulation and antioxidant activity. They are more palatable ingredients in dietary supplements than capsaicinoids because of their low pungency. Previous studies on nonpungent Capsicum annuum cultivars showed that capsinoid biosynthesis is caused by loss-of-function putative aminotransferase (p-amt) alleles. This study showed that three mildly pungent cultivars of Capsicum chinense (Zavory Hot, Aji Dulce strain 2, and Belize Sweet) contain high levels of capsinoid. It was shown that these cultivars have novel p-amt alleles, which contain mutations that differ from those of C. annuum. Sequence analysis of p-amt in Belize Sweet revealed that a 5 bp insertion (TGGGC) results in a frameshift mutation. A transposable element (Tcc) was found in the p-amt of Zavory Hot and Aji Dulce strain 2. Tcc has features similar to those of the hAT transposon family. This was inserted in the fifth intron of Zavory Hot and in third intron of Aji Dulce strain 2. The p-amt alleles harboring Tcc cannot produce an active p-AMT. These mildly pungent cultivars will provide a new natural source of capsinoids. 相似文献