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441.
Stimulation of Toll-like receptors (TLRs) triggers activation of a common MyD88-dependent signaling pathway as well as a MyD88-independent pathway that is unique to TLR3 and TLR4 signaling pathways leading to interferon (IFN)-beta production. Here we disrupted the gene encoding a Toll/IL-1 receptor (TIR) domain-containing adaptor, TRIF. TRIF-deficient mice were defective in both TLR3- and TLR4-mediated expression of IFN-beta and activation of IRF-3. Furthermore, inflammatory cytokine production in response to the TLR4 ligand, but not to other TLR ligands, was severely impaired in TRIF-deficient macrophages. Mice deficient in both MyD88 and TRIF showed complete loss of nuclear factor kappa B activation in response to TLR4 stimulation. These findings demonstrate that TRIF is essential for TLR3- and TLR4-mediated signaling pathways facilitating mammalian antiviral host defense.  相似文献   
442.
The 18S rRNA genes of Theileria species detected in sika deer, Cervus nippon centralis in Yamaguchi and Cervus nippon yesoensis in Hokkaido, were analyzed. The percent identities of the nucleotide sequences of Theileria from Cervus nippon centralis and Cervus nippon yesoensis were more than 99%. The percent identities of the Theileria sp. from sika deer and Theileria sergenti, Theileria buffeli and Theileria cervi were 97, 96 and 95%, respectively. Phylogenetic analysis of the gene sequences also revealed that Theileria sp. detected from sika deer comprise a clade that is clearly distinct from the clade comprised of Theileria from cattle.  相似文献   
443.
Repetitive DNA sequences, ManDra and ManBgl, were isolated from the DraI and BglII digests of the genomic DNA of Misgurnus anguillicaudatus, respectively. A primer set of ManDra distinguished two genetically different groups (A and B) of M. anguillicaudatus by specific electrophoretograms. A primer set of ManBgl amplified the DNA of M. anguillicaudatus and M. mizolepis. The individuals of M. anguillicaudatus were divided into two groups depending on the fragment sizes, in which the groups A and B (B-1 and B-2) showed 400 and 460 bp, respectively. M. mizolepis was distinguished by a different pattern (400-, 460-, and 510-bp fragments). PCR–RFLP analyses of recombination activating gene 1 gave a clear difference between A or B-2 (443-bp fragment) and B-1 groups (296- and 147-bp fragments). Clonal lineages and hybrids between B-1 and B-2 groups could be identified by appearance of three fragments (443, 296, and 147 bp). The combined analyses using the above three nuclear markers discriminated among nuclear genomes of genetic groups (A, B-1 and B-2) of M. anguillicaudatus and M. mizolepis. In several localities, natural hybridizations between the group B-1 and B-2 loaches and introgressions of clonal mitochondrial genomes into the group B-1 loaches were detected.  相似文献   
444.
The agricultural fields were contaminated by the radionuclides 134Cs and 137Cs after the nuclear power plant accident in Fukushima. Prior to the accident, local farmers had successfully established sustainable agriculture in Iitate Village using natural farming practices and recycling. Since 2011, decontamination work such as stripping-off the top soil has been ongoing on agricultural land. Although decontamination is essential, it could cause an unfortunate decrease in soil fertility. Here, we examined the use of organic matter as a means to quickly recover the fertility of the agricultural top soil. We transplanted rice crops into three paddy plots: one received rice straw that had been harvested there last year, another received composted manure, and the third (control) received no additives after decontamination. We applied 40 kg/10a of basal fertilizer and 20 kg/10a of KCl each plot. The rates of Cs concentration in unhulled rice/rice straw were around 0.001. Tendency of plant heights increase and leaf chlorophyll content decrease were similar in the three treatment plots. However, the numbers of stems on 111 days after the transplant were 21, 15, and 19, unhulled rice yield were 513, 462, and 310 g/m2, in the rice straw, cattle manure compost, and control plots, respectively. Soil properties of three plots were similar. Radioactive Cs concentrations in the new rice from each treatment plots were lower than the maximum allowed level set by the Japanese government. These results revealed that treating soil with rice straw might have great potential to aid the recovery of a paddy field after stripping-off the top soil. Notably, this treatment significantly improved the yield of rice and supplied organic matter without additional labor.  相似文献   
445.
ABSTRACT:   A glycerolipid acyl-hydrolase was purified 19-fold with a yield of 11% from the prostaglandin-producing red alga Gracilaria vermiculophylla by ammonium sulfate precipitation, anion-exchange chromatoraphy and gel filtration chromatography. Sodium dodecylsulfate– polyacrylamide gel electrophoresis of the final preparation showed a single band corresponding to a molecular mass of 20 kDa, but Superdex 200 fast protein liquid chromatography exhibited a molecular mass of 40 kDa. Accordingly, it was suggested that the purified enzyme was a homodimer of a 20 kDa subunit. The optimal temperature and pH were 37°C and 7–8, respectively. The purified enzyme catalyzed hydrolysis of the acyl groups of both glycoglycerolipids and phospholipids, especially monogalactosyldiacylglycerol and phosphatidylcholine. These results suggest that the enzyme hydrolyze the membrane lipids of the alga to release various saturated and unsaturated fatty acids, including arachidonic acid as substrate for prostaglandin synthesis.  相似文献   
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