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491.
Dihydrochalcones are a class of secondary metabolites, whose demand in biological and pharmacological applications is rapidly growing. Phloretin is one of the best known and abundant dihydrochalcone characterized by the presence of 2,6-dihydroxyacetophenone pharmacophore. It is a versatile molecule with anticancer, antiosteoclastogenic, antifungal, antiviral, anti-inflammatory, antibacterial and estrogenic activities and able to increase the fluidity of biological membranes and penetration of administered drugs. In this review we have performed a critical evaluation of available literature as far as phloretin beneficial effects and activation/block of intracellular signal cascade are of concern. In addition, we supply useful information on its chemical properties, sources and bioavailability.  相似文献   
492.
Molecular Biology Reports - 10-Dehydrogingerdione (10-DHGD) was previously reported to possess a hypolipidemic, anti-inflammatory and anti-oxidant properties in hyperlipidemic rabbit model. In this...  相似文献   
493.
494.
Inflammation is associated with the development of several diseases comprising cancer and cardiovascular disease. Agents that suppress cyclooxygenase (COX) and lipoxygenase (LOX) enzymes, besides chemokines have been suggested to minimise inflammation. Here, a variety of novel heterocyclic and non-heterocyclic compounds were prepared from novel three furanone derivatives. The structures of all synthesised compounds were confirmed by elemental and spectral analysis including mass, IR, and 1H-NMR spectroscopy. Anti-inflammatory activities of these synthesised compounds were examined in vitro against COX enzymes, 15-LOX, and tumour necrosis factor-α (TNF-α), using inhibition screening assays. The majority of these derivatives showed significant to high activities, with three pyridazinone derivatives (5b, 8b, and 8c) being the most promising anti-inflammatory agents with dual COX-2/15-LOX inhibition activities along with high TNF-α inhibition activity.  相似文献   
495.
In this study, the ability of safflower-isolated root cultures to produce yellow pigments was tested. Initially, the growth of isolated roots in static liquid medium was evaluated with different volumes of culture medium. A volume of 6 ml of medium per flask of 250 ml gave the best growth performance and, in this condition of culture, production of pigments from isolated roots treated or not by light has been determined by spectrophotometry (321 and 400 nm). Under these conditions, the production of yellow pigments amounted to 13.18 mg g−1 fresh weight and the light stimulated the synthesis of these pigments by isolated roots. Total yellow pigments of 24.12, 38.91 and 46.38 mg g−1 fresh weight was produced by the roots treated with 9, 13.5 and 18% (v/v) gas oil, respectively, representing high values of production. The pigments were released in large quantities in the medium. The increased synthesis of pigments as a result of gas oil treatment was accompanied by a reduction of the peroxidase activity of roots. Given the high production of yellow pigments, systems of isolated root culture could be considered for the study of a larger scale production of safflower pigments widely used for various industrial purposes.  相似文献   
496.
Physiology and Molecular Biology of Plants - In this study, changes in growth, yield and photosynthetic characteristics were assessed by foliar application of triacontanol (TRIA) in wheat (Triticum...  相似文献   
497.
Environmental Vibrio strains represent a major threat in aquaculture, but the understanding of their virulence mechanisms heavily relies on the transposition of knowledge from human-pathogen vibrios. Here, the genetic bases of the virulence of Vibrio harveyi ORM4 towards the European abalone Haliotis tuberculata were characterized. We demonstrated that luxO, encoding a major regulator of the quorum sensing system, is crucial for the virulence of this strain, and that its deletion leads to a decrease in swimming motility, biofilm formation, and exopolysaccharide production. Furthermore, the biofilm formation by V. harveyi ORM4 was increased by abalone serum, which required LuxO. The absence of LuxO in V. harveyi ORM4 yielded opposite phenotypes compared with other Vibrio species including V. campbellii (still frequently named V. harveyi). In addition, we report a full type III secretion system (T3SS) gene cluster in the V. harveyi ORM4 genome. LuxO was shown to negatively regulate the promoter activity of exsA, encoding the major regulator of the T3SS genes, and the deletion of exsA abolished the virulence of V. harveyi ORM4. These results unveil virulence mechanisms set up by this environmentally important bacterial pathogen and pave the way for a better molecular understanding of the regulation of its pathogenicity.  相似文献   
498.
In this study, co-delivery system was achieved via plasmid encoding TNF related apoptosis inducing ligand (pTRAIL) and doxorubicin (DOX) using carrier based on polypropylenimine (PPI) modified with 10-bromodecanoic acid. Incorporation of alkylcarboxylate chain to PPIs (G4 and G5) could improve transfection efficiency via overcoming the plasma membrane barrier of the cells and decrease cytotoxicity of PPI. Characterization of fabricated NPs revealed that PPI G5 in which 30% of primary amines were substituted by alkyl carboxylate chain (PPI G5-Alkyl 30%) has higher drug loading as compared to the other formulations. PPI G5-Alkyl 30% indicated a decreased drug release may be due to alkyl chains on the surface of PPI, which serve as an additional hindrance for drug diffusion. In vitro cytotoxicity experiments demonstrated that co-delivery system induced apoptosis of tumor cells more efficiently than each of delivery system alone. Furthermore, these results revealed that our combined delivery platform of pTRAIL and DOX using Alkyl-modified PPI G5 can significantly improve the anti-tumor activity and this strategy might develop a new therapeutic window for cancer treatment.  相似文献   
499.
Upper rim phosphonic acid functionalized calix[4]arene affects selective transport of multiple molecular payloads through a liquid membrane. The secret is in the attachment of a receptor-complementary handle to the payload. We find that the trimethylammonium ethylene group present in choline is one of several general handles for the transport of drug and drug-like species. Herein we compare the effect of handle variation against the transport of serotonin and dopamine. We find that several ionizable amine termini handles are sufficient for transport and identify two ideal candidates. Their performance is significantly enhanced in HEPES buffered solutions. This inquiry completes a series of 3 studies aimed at optimization of this strategy. In completion a new approach towards synthetic receptor mediated selective small molecule transport has emerged; future work in vesicular and cellular systems will follow.  相似文献   
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