Search results for "Avon"
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Aroniju ogu fitoķīmiskā sastāva izvērtējums
2019
Aroniju ogu fitoķīmiskā sastāva izvērtēšana. Batarāga A. Zinātniskā vadītāja Asoc.prof. Dr. ķīm. Prikšāne A., konsultante Mg.ķīm. Valkovska V. Maģistra darbs, 76 lappuses, 46 attēli, 20 tabulas, 44 literatūras avoti. Latviešu valodā. Darbā analizēts aroniju ogu fitoķīmiskais sastāvs, nosakot kopējo fenolu, flavonoīdu saturu un antiradikālo aktivitāti. Lai pagatavotu analizējamos paraugus, izmantotas gan sasaldētas, gan ţāvētas ogas un kā ekstrahenti – 70 % etanola/ūdens, 10 % glicerīna/etanola un daţādu koncentrāciju un pH vērtību etanola/ūdens/HCl maisījumi. Pēc ultraskaľas veicinātas ekstrakcijas un 1 – 3 nedēļu ilgas macerācijastika noteikts kopējo fenolu saturs, izmantojot FolinCiocalte…
Characterization of particle morphology of biochanin A molecularly imprinted polymers and their properties as a potential sorbent for solid-phase ext…
2014
Abstract Molecularly imprinted polymers (MIPs) with biochanin A as a template were obtained using a bulk polymerization with non-covalent imprinting approach. The polymers were prepared in acetonitrile as porogen, using ethylene glycol dimethacrylate (EDMA) as cross-linking agent. The synthesis, with an application of 1′,1′-azobis(cyclohexanecarbonitrile) (ACHN) as an initiator, has been performed thermally. During the synthesis process the effect of different functional monomers such as methacrylic acid (MAA), acrylamide (AA) and 4-vinylpyridine (4-VP) was investigated. The application of nitrogen sorption porosimetry, scanning electron microscopy (SEM), and Fourier transform infrared spec…
Inhibition of skin inflammation by baicalin ultradeformable vesicles.
2016
The topical efficacy of baicalin, a natural flavonoid isolated from Scutellaria baicalensis Georgi, which has several beneficial properties, such as antioxidative, antiviral, anti-inflammatory and antiproliferative, is hindered by its poor aqueous solubility and low skin permeability. Therefore, its incorporation into appropriate phospholipid vesicles could be a useful tool to improve its local activity. To this purpose, baicalin at increasing concentrations up to saturation, was incorporated in ultradeformable vesicles, which were small in size (∼67nm), monodispersed (PI<0.19) and biocompatible, regardless of the concentration of baicalin, as confirmed by in vitro studies using fibroblasts…
Effect of single-dose and short-term administration of quercetin on the pharmacokinetics of talinolol in humans – Implications for the evaluation of …
2013
Quercetin has been shown to inhibit intestinal P-glycoprotein-mediated drug efflux. A crossover clinical study was performed in 10 healthy volunteers to assess the effect of single-dose and repeated quercetin intake on the pharmacokinetics of talinolol, a substrate of intestinal P-glycoprotein. Unexpectedly, mean area under the plasma concentration-time curve (AUC0-48h) and maximal plasma concentration (cmax) were slightly decreased following concomitant and short-term quercetin administration (3186.0 versus 2468.3 and 2527.7 ng h/ml, p>0.05; 309.7 versus 212.0 and 280.6 ng/ml, p>0.05). Individual analysis revealed that talinolol AUC0-48h was lowered by 23.9% up to 60.6% in 5 subjects and c…
An Alginate/Cyclodextrin Spray Drying Matrix to Improve Shelf Life and Antioxidant Efficiency of a Blood Orange By-Product Extract Rich in Polyphenol…
2017
Alginate and β-cyclodextrin were used to produce easily dosable and spray-dried microsystems of a dried blood orange extract with antidysmetabolic properties, obtained from a by-product fluid extract. The spray-dried applied conditions were able to obtain a concentrate dried extract without the loss of AOA and with TPC and TMA values of 35–40% higher than that of the starting material. They were also effective in producing microparticles with 80–100% of encapsulation efficiency. The 2% sodium alginate was capable of improving the extract shelf life, while the beta-cyclodextrin (1 : 1 molar ratio with dried extract) prolonged the extract antioxidant efficiency by 6 hours. The good inhibition…
Lifelong soya consumption in males does not increase lifespan but increases health span under a metabolic stress such as type 2 diabetes mellitus.
2021
Soya consumption can decrease oxidative stress in animal models. Moreover, phytoestrogens such as genistein, present in soya, can mimic some of the beneficial effects of estrogens and are devoid of significant side effects, such as cancer. In this study, we have performed a controlled lifelong study with male OF1 mice that consumed either a soya-free diet or a soya-rich diet. We show that, although we found an increase in the expression and activity of antioxidant enzymes in soya-consuming mice, it did not increase lifespan. We reasoned that the soya diet could not increase lifespan in a very healthy population, but perhaps it could extend health span in stressed animals such as type 2 diab…
Modulatory effects of the novel TrkB receptor agonist 7,8-dihydroxyflavone on synaptic transmission and intrinsic neuronal excitability in mouse visu…
2013
7,8-Dihydroxyflavone (7,8 DHF) is a new recently identified TrkB receptor agonist, which possesses a potent neurotrophic activity and shares many physiological properties with the neurotrophin "Brain Derived Neurotrophic Factor" (BDNF). However, its precise mechanism of action at the cellular level has not been clarified yet. In the present study we explored the effects of this agent on synaptic and intrinsic neuronal properties by performing whole-cell patch clamp recordings from layer 2/3 pyramidal neurons. Incubation of acute cortical slices with 7,8-DHF (20 µM) for 30 min caused a selective reduction in the strength of GABAergic inhibition. The amplitude of evoked inhibitory postsynapti…
Genistein effect on cognition in prodromal Alzheimer's disease patients : the GENIAL clinical trial
2022
Background: Delaying the transition from minimal cognitive impairment to Alzheimer’s dementia is a major concern in Alzheimer’s disease (AD) therapeutics. Pathological signs of AD occur years before the onset of clinical dementia. Thus, long-term therapeutic approaches, with safe, minimally invasive, and yet efective substances are recommended. There is a need to develop new drugs to delay Alzheimer’s dementia. We have taken a nutritional supplement approach with genistein, a chemically defned polyphenol that acts by multimodal specifc mechanisms. Our group previously showed that genistein supplementation is efective to treat the double transgenic (APP/PS1) AD animal model. Methods: In this…
Anti-inflammatory and analgesic activities of flavonoid and saponin fractions from Zizyphus lotus (L.) Lam.
2008
Abstract The effect of the flavonoid and saponin fractions from the leaves and root bark of Zizyphus lotus (200 mg/kg) was evaluated on carrageenan-induced paw edema in rats and on acetic acid-induced algesia in mice. In addition, two methanolic extracts from the plant (1 mg/ear) were tested on oxazolone-induced contact-delayed hypersensitivity (DTH) in mice. The effect of the different fractions was also evaluated in vitro on the nitrite production induced by lipopolysaccharide (LPS) in RAW 264.7 macrophages. The results showed that both the flavonoid and saponin fractions significantly inhibited paw edema, algesia, and nitrite production without affecting cell viability. Furthermore, the …
Central role of IL-6 and MMP-1 for cross talk between human intestinal mast cells and human intestinal fibroblasts.
2012
Mast cells (MC) are key effector cells in allergic reactions but also involved in host defence, tissue remodeling, angiogenesis, and fibrogenesis. Here, we show that human intestinal fibroblasts (FB) suppress apoptosis in human intestinal MC dependent on IL-6. Intestinal FB produced IL-6 upon direct stimulation by intestinal MC in co-culture or by MC mediators such as TNF-α, IL-1β, tryptase or histamine. MC incubated with IL-6 survived for up to 3 weeks similar to MC co-cultured with FB and MC survival could be blocked by neutralizing anti-IL-6 Abs. Moreover, FB stimulated by MC mediators upregulated their expression of matrix metalloproteinase-1 (MMP-1), a key fibrolytic enzyme. Noteworthy…