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Abstract: Melatonin and serotonin have previously been described in mature wine grapes and finished wines, but the metabolism of these signalling molecules in the development of wine grapes has not previously been investigated. We harvested wine grapes at different stages of development from lag phase through véraison from eight different commercial vineyards representing a diversity of growing conditions, management practices, merlot varietals and localized ecosystems to determine whether different patterns in melatonin and serotonin can be found in wine grapes during seed development and berry maturation. Melatonin was detected in 45% of the fully developed purple, postvéraison grapes but only found in 23% of prelag phase samples. However, the actual concentration of melatonin was highest in wine grapes harvested at the early stage of véraison when the seed is developing. Serotonin was not detected in any of the prelag phase grapes but was consistently detected in 30–35% of grapes harvested during the véraison transition at consistent levels of about 8–10 μg/g. Interestingly, the nitrogen storage compound γ‐aminobutyric acid was also found at about 115 μg/g in 77% of early stage green grapes and declined in both prevalence and concentration with ripening. Together, these data are indicative of a potential role for these molecules in the development and maturation of wine grapes.  相似文献   
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A layer‐by‐layer approach is used to anchor small gold nanoparticles onto organic nanotubes resulting from the self‐assembly and polymerization of diacetylene‐containing nitrilotriacetic amphiphiles. The obtained nanotube–gold hybrid is used as a catalyst for the aerobic oxidation of various silanes. With minimal gold loading (0.05 mol%), all substrates are converted into the corresponding silanols with hydrogen gas as the only by‐product. The catalyst operates under mild conditions and can be easily recycled, losing neither activity nor selectivity.

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Context: Aceclofenac is an important NSAID; however, it causes GI disturbances whereas employing transdermal route would require permeation enhancer for systemic application, thereby causing skin damage. Ceramide 2 is a natural lipid having an important role in the maintenance of skin. Objective: Aceclofenac-loaded nanovesicles of ceramide-2, cholesterol, palmitic acid, and cholesteryl sulfate were formulated and analyzed for physical and biological properties. Materials and method: Film hydration method was used to prepare the vesicles and physical parameters, in vitro drug release and stability were evaluated. Then, they were formulated into gel and evaluated against a commercial formulation (CF) and gel-containing plain drug (CPG) for ex vivo, in vivo drug permeation, and anti-inflammatory activity. Results: The developed formulations showed best physical profile and ACV-1 gave 92.89% drug release in in vitro studies. Ex vivo studies showed drug permeation between 15.32–31.12?μg/cm2, whereas CPG and CF released 0.47 and 2.81?μg/cm2, respectively. ACVG-1 and CF showed Cmax of 8.1 and 1.2?μg/ml at 8 and 4?h, respectively. ACVG-1 showed 11.6 times AUC than CF. ACVG-1 inhibited edema by 44% in first hour itself. Discussion: Ceramide 2 and palmitic acid played an important role in the formulation and promotes the drug permeation through stratum corneum and dermis. Ceramide content of the formulation also contributes towards stability and skin protection. Conclusion: The composition of the vesicle formulation performs an important role in physical properties and drug permeation, thereby producing an optimum formulation.  相似文献   
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