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81.
82.

Background  

Many types of weighting methods, which have integrated the various environmental impacts that are used for life-cycle impact assessment (LCIA), were proposed with the aim of developing the methodology as a useful information resource for decision making, such as in the selection of products. Economic valuation indexes, in particular, have attracted attention, as their assessment results are easy to understand and can be applied in conjunction with other assessment tools, including life-cycle costing (LCC) and environmental accounting. Conjoint analysis has been widely used in market research, and has recently been applied to research in environmental economics. The method enables us to provide two types of assessment results; an economic valuation and a dimensionless index. This method is therefore expected to contribute greatly to increasing the level of research into weighting methodology, in which an international consensus has yet to be established. Conjoint analysis, however, has not previously been applied to LCIA.  相似文献   
83.
The new brassinosteroid conjugate, teasterone-3-O-betaD-glucopyranoside, was found as a metabolite of teasterone in lily cell suspension cultures. Its structure was determined by means of FAB-MS and 1H-NMR upon comparison with the authentic compound. Furthermore, its presence in lily anthers was confirmed by FAB-MS and LC-APCI-SIM data. This is the first natural brassinosteroid conjugate glucosylated at a hydroxyl group in ring A.  相似文献   
84.
We evaluated the levels of (-)-epicatechin (EC) and its metabolites in plasma and urine after intake of chocolate or cocoa by male volunteers. EC metabolites were analyzed by HPLC and LC/MS after glucuronidase and/or sulfatase treatment. The maximum levels of total EC metabolites in plasma were reached 2 hours after either chocolate or cocoa intake. Sulfate, glucuronide, and sulfoglucuronide (mixture of sulfate and glucuronide) conjugates of nonmethylated EC were the main metabolites present in plasma rather than methylated forms. Urinary excretion of total EC metabolites within 24 hours after chocolate or cocoa intake was 29.8 ± 5.3% and 25.3 ± 8.1% of total EC intake. EC in chocolate and cocoa was partly absorbed and was found to be present as a component of various conjugates in plasma, and these were rapidly excreted in urine.  相似文献   
85.
The protective activity of rosmarinic acid from Perilla frutescens on liver injury induced by LPS in D-GalN-sensitized mice was examined. We also investigated the effects of antitumor necrosis factor-alpha antibody (anti-TNF), superoxide dismutase (SOD), and aminoguanidine (AG) on this model in order to elucidate the mechanism of rosmarinic acid protection. Perilla extract (PE) and rosmarinic acid (RA) treatments significantly reduced the elevation of plasma asparatate aminotransferase levels, as well as anti-TNF and SOD treatment, compared with controls, but this reduction was not seen in the AG group. These results were confirmed by histological examination using hematoxylin-eosin and in situ terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) staining. Increases in tumor necrosis factor-alpha (TNF-alpha) mRNA expression in liver and in plasma TNF-alpha levels, which were observed in control mice, were not significantly reduced by PE or RA. PE and RA treatments also did not significantly diminish iNOS mRNA expression or plasma nitrate/nitrite levels. Nitrotyrosine and N(epsilon)-(hexanonyl)lysine (HEL) production, the residue of oxidative stress, was observed in livers from controls, but not in those mice pretreated with PE or RA. These results suggest that the liver protection of RA is due to the scavenging or reducing activities-superoxide or peroxynitirite rather than to inhibition of TNF-alpha production.  相似文献   
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87.
In the canonical Wnt signaling pathway, the translocation of β-catenin is important for the activation of target genes in the nucleus. However, the molecular mechanisms underlying its nuclear localization remain unclear. In the present study, we found IQGAP1 to be a regulator of β-catenin function via importin-β5. In Xenopus embryos, depletion of IQGAP1 reduced Wnt-induced nuclear accumulation of β-catenin and expression of Wnt target genes during early embryogenesis. Depletion of endogenous importin-β5 associated with IQGAP1 also reduced expression of Wnt target genes and the nuclear localization of IQGAP1 and β-catenin. Moreover, a small GTPase, Ran1, contributes to the nuclear translocation of β-catenin and the activation of Wnt target genes. These results suggest that IQGAP1 functions as a regulator of translocation of β-catenin in the canonical Wnt signaling pathway.  相似文献   
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89.
CYP78 is a plant-specific family of cytochrome P450 monooxygenases, some members of which regulate the plastochron length and organ size in angiosperms. The CYP78 family appears to be highly conserved in land plants, but there have been no reports on the role of CYP78s in bryophytes. The moss, Physcomitrella patens, possesses two CYP78As, CYP78A27 and CYP78A28. We produced single and double mutants and overexpression lines for CYP78A27 and CYP78A28 by gene targeting to investigate the function of CYP78As in P. patens. Neither the cyp78a27 nor cyp78a28 single mutant showed any obvious phenotype, while the double mutant exhibited severely retarded protonemal growth and gametophore development. The endogenous levels of some plant hormones were also altered in the double mutant. Transgenic lines that overexpressed CYP78A27 or CYP78A28 showed delayed and reduced bud formation. Our results suggest that CYP78As participate in the synthesis of a critical growth regulator in P. patens.  相似文献   
90.
Phytocassanes and momilactones are the major diterpenoid phytoalexins inductively produced in rice as bioactive substances. Regardless of extensive studies on the biosynthetic pathways of these phytoalexins, bioconversion of diterpene hydrocarbons is not shown in planta. To elucidate the entire biosynthetic pathways of these phytoalexins, uniformly 13C-labeled ent-cassadiene and syn-pimaradiene were enzymatically synthesized with structural verification by GC–MS and 13C-NMR. Application of the 13C-labeled substrates on rice leaves led to the detection of 13C-labeled metabolites using LC-MS/MS. Further application of this method in the moss Hypnum plumaeforme and the nearest out-group of Oryza species Leersia perrieri, respectively, resulted in successful bioconversion of these labeled substrates into phytoalexins in these plants. These results demonstrate that genuine biosynthetic pathways from these diterpene hydrocarbons to the end product phytoalexins occur in these plants and that enzymatically synthesized [U-13C20] diterpene substrates are a powerful tool for chasing endogenous metabolites without dilution with naturally abundant unlabeled compounds.  相似文献   
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