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191.
Javier Antunez-Solis Fernando Hernández-Derramadero Mayda Aquino-Vega Selene Ibarra-Ramírez Lorena Rodríguez-Páez Isabel Baeza 《Journal of enzyme inhibition and medicinal chemistry》2013,28(3):903-909
2,4,5-trimethoxycinnamic acid (TMC), the major and non toxic metabolite of α-asarone (2,4,5-trimethoxy-1-propenyl benzene), retains most of the pharmacological properties of α-asarone, since both substances, administered to hypercholesterolemic rats at 80 mg/kg body wt, decreased total serum cholesterol, lowered LDL-cholesterol levels and kept unaffected HDL-cholesterol levels. In addition, both substances increased bile flow, especially in hypercholesterolemic rats, by rising the secretion of bile salts, phospholipids and bile cholesterol. These drugs also reduced cholesterol levels of gallbladder bile, whereas phospholipids and bile salts concentrations were increased, decreasing the cholesterol saturation index (CSI). We also found that α-asarone was 20 times better inhibitor of HMG-CoA reductase than TMC. This effect on HMG-CoA reductase was the only property highly reduced in TMC in comparison with α-asarone, while the other pharmacological properties of α-asarone were retained by TMC. These experiments strongly suggest that TMC can be further studied as a possible hypocholesterolemic and cholelitholytic agent. 相似文献
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Baeza M Flores O Carrasco M Rozas JM Oviedo V Barahona S Cifuentes V 《Journal of microbiology (Seoul, Korea)》2010,48(6):822-828
In this study, the existence of intra-specific and inter-generic fungicidal activity in Xanthophyllomyces dendrorhous and Phaffia rhodozyma strains isolated from different regions of the earth was examined. Assays were performed under several culture conditions,
showing that all the analyzed X. dendrorhous and P. rhodozyma strains have killing activity against Kloeckera apiculata, Rhodotorula sloffiae, and R. minuta. This activity was greater in rich media at a pH from 4.6 to 5.0. Extracellular protein extracts with fungicidal activity
were obtained from cultures of all strains, and their characterization suggested that a protein of 33 kDa is the antifungal
factor. According to peptide mass fingerprinting and an analysis of the results with the MASCOT search engine, this protein
was identified as an aspartic protease. Additionally, extrachromosomal double-stranded DNA elements (dsDNAs) were observed
in all X. dendrorhous and P. rhodozyma strains. Although there is a high variability, two dsDNAs of 5.4 and 6.8 kb are present in all strains. 相似文献
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196.
Jonathan CM Clark Toru Akiyama Crispin R Dass Peter FM Choong 《Cancer cell international》2010,10(1):20
Background
Chondrosarcoma responds poorly to adjuvant therapy and new, clinically relevant animal models are required to test targeted therapy. 相似文献197.
Pirie MD Humphreys AM Galley C Barker NP Verboom GA Orlovich D Draffin SJ Lloyd K Baeza CM Negritto M Ruiz E Sanchez JH Reimer E Linder HP 《Molecular phylogenetics and evolution》2008,48(3):1106-1119
Phylogeny reconstruction is challenging when branch lengths vary and when different genetic loci show conflicting signals. The number of DNA sequence characters required to obtain robust support for all the nodes in a phylogeny becomes greater with denser taxon sampling. We test the usefulness of an approach mixing densely sampled, variable non-coding sequences (trnL-F; rpl16; atpB-rbcL; ITS) with sparsely sampled, more conservative protein coding and ribosomal sequences (matK; ndhF; rbcL; 26S), for the grass subfamily Danthonioideae. Previous phylogenetic studies of Danthonioideae revealed extensive generic paraphyly, but were often impeded by insufficient character and taxon sampling and apparent inter-gene conflict. Our variably-sampled supermatrix approach allowed us to represent 79% of the species with up to c. 9900 base pairs for taxa representing the major clades. A 'taxon duplication' approach for taxa with conflicting phylogenetic signals allowed us to combine the data whilst representing the differences between chloroplast and nuclear encoded gene trees. This approach efficiently improves resolution and support whilst maximising representation of taxa and their sometimes composite evolutionary histories, resulting in a phylogeny of the Danthonioideae that will be useful both for a wide range of evolutionary studies and to inform forthcoming realignment of generic delimitations in the subfamily. 相似文献
198.
The metabolism of polyphosphate accumulating organisms (PAOs) has been widely studied through the use of lab-scale enrichments. Various metabolic models have been formulated, based on the results from lab-scale experiments using enriched PAO cultures. A comparison between the anaerobic stoichiometry predicted by metabolic models with that exhibited by full-scale sludge in enhanced biological phosphorus removal (EBPR) wastewater treatment plants (WWTPs) was performed in this study. Batch experiments were carried out with either acetate or propionate as the sole carbon source, using sludges from two different EBPR-WWTPs in Australia that achieved different phosphorus removal performances. The results support the hypothesis that the anaerobic degradation of glycogen is the primary source of reducing equivalents generated by PAOs, however, they also suggested a partial contribution of the tricarboxylic acid (TCA) cycle in some cases. The experimental results obtained when acetate was the carbon source suggest the involvement of the modified succinate-propionate pathway for the generation of poly-beta-hydroxyvalerate (PHV). Overall, the batch test results obtained from full-scale EBPR sludge with both substrates were generally well described by metabolic model predictions for PAOs. 相似文献
199.
Theory predicts that monogamy is adaptive in resource-specialist symbiotic crustaceans inhabiting relatively small and morphologically simple hosts in tropical environments where predation risk away from hosts is high. We tested this prediction in Pontonia manningi, a hyper-symbiotic shrimp that dwells in the mantle cavity of the Atlantic winged oyster Pteria colymbus that, in turn, infects gorgonians from the genus Pseudopterogorgia in the Caribbean Sea. In agreement with theory, P. manningi were found dwelling as heterosexual pairs in oysters more frequently than expected by chance alone. Males and females also inhabited the same host individual independent of the female gravid condition or of the developmental stage of brooded embryos. While the observations above argue in favor of monogamy in P. manningi, there is evidence to suggest that males of the studied species are moderately promiscuous. That females found living solitary in oysters most often brooded embryos, and that males allocated more to weaponry (major claw size) than females at any given size suggest that males might be roaming among host individuals in search of and, fighting for, receptive females. All available information depicts a rather complex mating system in P. manningi: primarily monogamous but with moderately promiscuous males. 相似文献
200.