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21.
This study aims to understand Th2 immune responses and alternative macrophage activation against nematode parasites in aged mice. Eighteen-month (18 M) and three-month (3 M) old C3H/HeN mice were inoculated with Heligmosomoides polygyrus (Hp) larvae. Real-time PCR analysis indicated that interleukin (IL)-4 and IL-13 gene expression was elevated in both groups after infection, but the expression level was significantly low in 18 M mice. Macrophage phenotype was monitored by measuring arginase-1 gene expression and immunofluorescence staining in small intestine, showing a decrease in the number of alternatively activated macrophages (AAMacs) around worm cysts in 18 M mice. These results suggest that the Th2 immune response in aged mice against a nematode parasite was not sufficiently induced to promote AAMacs.  相似文献   
22.
The 2011 earthquake severely damaged the Fukushima Daiichi Nuclear Power Plant (FNPP), resulting in the release of large quantities of radioactive material into the environment. The deposition of these radionuclides in rice straw as livestock feed led to the circulation of contaminated beef in the market. Based on the safety concern of the consumers, a reliable method for estimating concentrations of radioactive cesium in muscle tissue is needed. In this study, we analyzed the concentrations of radioactive cesium in the blood and skeletal muscle of 88 cattle, and detected a linear correlation between them. We then developed software that can be used to estimate radioactive cesium concentrations in muscle tissue from blood samples. Distribution of this software to the livestock production field would allow us to easily identify high‐risk cattle, which would be beyond the safety regulation, before shipping out to the market. This software is planned to be released as freeware. This software would contribute to food safety, and aid the recovery of the livestock industry from the damage creacted by the 2011 Tohoku earthquake and tsunami.  相似文献   
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The accident at the Fukushima Daiichi Nuclear Power Plant (FNPP) released a large amount of radioactive substances into the environment. Furthermore, beef contaminated with radioactive cesium above the 500 Bq/kg safety standard was circulated in the food chain in 2011. Japanese consumers remain concerned about the safety of radioactively contaminated food. In our previous study, we detected a linear correlation between radioactive cesium (137Cs) activity in blood and muscle around 500 to 2500 Bq/kg in cattle. However, it was unclear whether the correlation was maintained at a lower radioactivity close to the current safety standard of 100 Bq/kg. In this study, we evaluated 17 cattle in the FNPP evacuation zone that had a 137Cs blood level less than 10 Bq/kg. The results showed a linear correlation between blood 137Cs and muscle 137Cs (Y = 28.0X, R2 = 0.590) at low radioactivity concentration, indicating that cesium radioactivity in the muscle can be estimated from blood radioactivity. This technique would be useful in detecting high‐risk cattle before they enter the market, and will contribute to food safety.  相似文献   
25.
RNA silencing is a sequence-specific defense mechanism against viruses. As a counterdefense, viruses evolved silencing suppressors to interfere with host silencing. In analyses using protoplasts prepared from cultured cells (BY-2) and mesophyll cells of Nicotiana tabacum and N. benthamiana, viral suppressors differentially functioned in different cell types. This phenomenon has not been discussed in earlier papers on protoplast systems and RNA silencing. In investigations of the cellular activities of viral suppressors and their role in the RNA-silencing pathway, assays with host protoplasts offer many advantages and can complement other in planta assays such as Agrobacterium-mediated transient expression.  相似文献   
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We extracted polyphenols from carob (Ceratonia siliqua L.) pods, and evaluated the in vitro antioxidant activity of the crude polyphenol fraction (CPP). The total polyphenol content in CPP determined by the Folin-Ciocalteu method was 19.2%. The condensed tannin content determined by the vanillin and proanthocyanidin assay systems was 4.37% and 1.36%, respectively. beta-Carotene bleaching, 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging, inhibition of lipid peroxidation by the erythrocyte ghost, and microsomal assay systems were used to evaluate the antioxidant activity. CPP showed a stronger inhibitory effect against the discoloration of beta-carotene than other polyphenol compounds such as catechins and procyanidins. CPP had weaker antioxidant activity in the DPPH free radical scavenging, the erythrocyte ghost, and microsomal systems than authentic polyphenol compounds at the same concentrations. The activity adjusted by the polyphenol concentration was, however, comparable to that of authentic polyphenol compounds. Considering most carob pods are discarded and not effectively utilized at present, these results suggested that carob pods could be utilized as a functional food or food ingredient.  相似文献   
28.
Genotypic Analysis of Heading Time on an Indica Rice Cultivar, Nanjing 11   总被引:1,自引:0,他引:1  
In this paper, the genotype of heading time in Nanjing 11, an indica variety, was analyzed bycrossing with tester varieties, Akihikari ( e1e1 e2e2 e3e3 Se1eSe1e ), Koshihikari ( E1E1E2E2 e3e3 Se1eSe1e ), Nipponbare(E1E1 e2e2 e3e3 Se1Se1 )and Hinohikari(E1E1 E2E2 e3e3 Se1Se1 ), of which the genotypes of headingtime were well known. The results showed genotype of heading time in Nanjing 11 was E1E1 e2e2 E3E3 Se1Se1and also included a recessive inhibitor I-Se1 for photoperiod-sensitivity as well. Meanwhile, the two photoperiod-sensitive genes, E1 and Se1, in Nanjing 11 were also identified by crossing with QTL nearly isogenic lines of Nipponbare, NIL( Hd1 )and NIL( Hd4 )which have complementary effects.  相似文献   
29.
In 1992 and 2002, investigations on the water quality and hydrology were carried out in a small agricultural catchment where swine waste was stored in earthen waste storage. The in-stream nitrogen loads and the nitrogen inputs on a sub-catchment scale were estimated and compared between 1992 and 2002. For the entire catchment, the estimated nitrogen inputs increased from 22.5 to 32.9 ton year−1 (from 406 to 594 kg ha−1 year−1), whereas the nitrate nitrogen concentration at the outlet was constant—27 mg l−1. In a sub-catchment (area C) with earthen waste storages, the nitrate nitrogen concentrations at the outlet were high, 42–51 mg l−1. In a sub-catchment (area A) with an earthen waste storage, which was not in service since 1990, although the nitrogen inputs were maintained at 390 kg year−1 (53 kg ha−1 year−1), the nitrate nitrogen concentrations at the outlet decreased from 26 to 4.9 mg l−1. With assuming that the nitrogen transport rates for sources except swine waste are equal to the rates estimated for a sub-catchment without earthen waste storage, the in-stream nitrogen loads for area A were estimated to decrease from 1,334 to 94 kg year−1 and the transport rates for area A were estimated to decrease from 3.95 to 0.73. These results suggest that the effluent from earthen waste storage has affected surface water quality two years after the storage was out of service and its effect largely decreased after a decade.  相似文献   
30.
In soil, downwardly growing plant roots frequently alter their growth direction to escape obstacles that lie in their paths. This response has been analyzed with a simple system that provides a constant obstacle-touching stimulus to root tips of young seedlings of Arabidopsis thaliana. On the surface of agar plates, which were set at an angle of 45 degrees to the vertical, the roots exhibit a wavy growth pattern that is caused by periodic reversion of rotation of the root tip. A set of mutants with abnormal wavy growth was used to demonstrate that at least six genes are involved in this stimulus-response interaction.  相似文献   
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