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1.
In recent years, there is emerging evidence that isoflavonoids, either dietary or obtained from traditional medicinal plants, could play an important role as a supplementary drug in the management of type 2 diabetes mellitus (T2DM) due to their reported pronounced biological effects in relation to multiple metabolic factors associated with diabetes. Hence, in this regard, we have comprehensively reviewed the potential biological effects of isoflavonoids, particularly biochanin A, genistein, daidzein, glycitein, and formononetin on metabolic disorders and long-term complications induced by T2DM in order to understand whether they can be future candidates as a safe antidiabetic agent. Based on in-depth in vitro and in vivo studies evaluations, isoflavonoids have been found to activate gene expression through the stimulation of peroxisome proliferator-activated receptors (PPARs) (α, γ), modulate carbohydrate metabolism, regulate hyperglycemia, induce dyslipidemia, lessen insulin resistance, and modify adipocyte differentiation and tissue metabolism. Moreover, these natural compounds have also been found to attenuate oxidative stress through the oxidative signaling process and inflammatory mechanism. Hence, isoflavonoids have been envisioned to be able to prevent and slow down the progression of long-term diabetes complications including cardiovascular disease, nephropathy, neuropathy, and retinopathy. Further thoroughgoing investigations in human clinical studies are strongly recommended to obtain the optimum and specific dose and regimen required for supplementation with isoflavonoids and derivatives in diabetic patients.  相似文献   
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Research on Chemical Intermediates - Volatile organic compounds (VOCs) represent a very important class of pollutants that causes serious health effects. There is an urgent requirement to establish...  相似文献   
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A predator–prey model with disease amongst the prey and ratio‐dependent functional response for both infected and susceptible prey is proposed and its features analysed. This work is based on previous mathematical models to analyse the important ecosystem of the Salton Sea in Southern California and New Mexico where birds (particularly pelicans) prey on fish (particularly tilapia). The dynamics of the system around each of the ecologically meaningful equilibria are presented. Natural disease control is considered before studying the impact of the disease in the absence of predators and the interaction of predators and healthy prey and the disease effects on predators in the absence of healthy prey. Our theoretical results are confirmed by numerical simulation. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
4.
The porcine pancreatic elastase inhibition and free-radical scavenging play a crucial role in age progression. All the series of 10 newly synthesized benzimidazole thioureas ( 4a-j ) were assessed for elastase inhibition and radical scavenging activity to identify the suitable anti-aging ingredient for cosmetics products. The compounds 4e , 4f , 4g , and 4h showed inhibition better than the standard, while compound 4f showed the most significant elastase inhibition with the IC50 value of 1.318 ± 0.025 μM compared with oleanic acid IC50 13.451 ± 0.014 used ±1.989 and 41.563 ± 0.824, respectively, as standard. Molecular docking studies were performed and the compound 4f showed binding energy of 7.2 kcal/mol. Kinetics studies revealed inhibition of the pancreatic elastase in a competitive manner. The relative binding energy and structure activity relationship (SAR) identified compound 4f as an effective inhibitor of porcine pancreatic elastase. Compounds 4e and 4i showed remarkable free-radical scavenging activity with SC50 values of 26.421.  相似文献   
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Targeting tyrosinase for melanogenesis disorders is an established strategy. Hydroxyl-substituted benzoic and cinnamic acid scaffolds were incorporated into new chemotypes that displayed in vitro inhibitory effects against mushroom and human tyrosinase for the purpose of identifying anti-melanogenic ingredients. The most active compound 2-((4-methoxyphenethyl)amino)-2-oxoethyl (E)-3-(2,4-dihydroxyphenyl) acrylate (Ph9), inhibited mushroom tyrosinase with an IC50 of 0.059 nM, while 2-((4-methoxyphenethyl)amino)-2-oxoethyl cinnamate (Ph6) had an IC50 of 2.1 nM compared to the positive control, kojic acid IC50 16700 nM. Results of human tyrosinase inhibitory activity in A375 human melanoma cells showed that compound (Ph9) and Ph6 exhibited 94.6% and 92.2% inhibitory activity respectively while the positive control kojic acid showed 72.9% inhibition. Enzyme kinetics reflected a mixed type of inhibition for inhibitor Ph9 (Ki 0.093 nM) and non-competitive inhibition for Ph6 (Ki 2.3 nM) revealed from Lineweaver–Burk plots. In silico docking studies with mushroom tyrosinase (PDB ID:2Y9X) predicted possible binding modes in the catalytic site for these active compounds. Ph9 displayed no PAINS (pan-assay interference compounds) alerts. Our results showed that compound Ph9 is a potential candidate for further development of tyrosinase inhibitors.  相似文献   
6.
The present research work is designed to prepare and evaluate piperine liposomes and piperine–chitosan-coated liposomes for oral delivery. Piperine (PPN) is a water-insoluble bioactive compound used for different diseases. The prepared formulations were evaluated for physicochemical study, mucoadhesive study, permeation study and in vitro cytotoxic study using the MCF7 breast cancer cell line. Piperine-loaded liposomes (PLF) were prepared by the thin-film evaporation method. The selected liposomes were coated with chitosan (PLFC) by electrostatic deposition to enhance the mucoadhesive property and in vitro therapeutic efficacy. Based on the findings of the study, the prepared PPN liposomes (PLF3) and chitosan coated PPN liposomes (PLF3C1) showed a nanometric size range of 165.7 ± 7.4 to 243.4 ± 7.5, a narrow polydispersity index (>0.3) and zeta potential (−7.1 to 29.8 mV). The average encapsulation efficiency was found to be between 60 and 80% for all prepared formulations. The drug release and permeation study profile showed biphasic release behavior and enhanced PPN permeation. The in vitro antioxidant study results showed a comparable antioxidant activity with pure PPN. The anticancer study depicted that the cell viability assay of tested PLF3C2 has significantly (p < 0.001)) reduced the IC50 when compared with pure PPN. The study revealed that oral chitosan-coated liposomes are a promising delivery system for the PPN and can increase the therapeutic efficacy against the breast cancer cell line.  相似文献   
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This article deals with the dynamical analysis of discrete-time Brusselator models. Euler’s forward and nonstandard difference schemes are implemented for discretization of Brusselator system. We investigate the local dynamics related to equilibria of both discrete-time models. Furthermore, with the help of bifurcation theory and center manifold theorem, explicit parametric conditions for directions and existence of flip and Hopf bifurcations are investigated. A novel chaos control method is implemented in order to control chaos in discrete-time Brusselator models under the influence of flip and Hopf bifurcations. Numerical simulations are provided to illustrate theoretical discussion and effectiveness of newly introduced chaos control strategy.  相似文献   
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In this work, the diffusion properties of single component n-heptane and toluene as well as their binary mixtures in two SBA-15 samples with different structural characteristics were studied by the standard Zero Length Column (ZLC) technique under three different concentration levels. A theoretical ZLC desorption model considering the Generalized Maxwell-Stefan (GMS) formulation was developed. Using the independently measured single component equilibrium and kinetic parameters, the model was able to reasonably predict experimental binary ZLC desorption curve for countercurrent diffusion of toluene in the presence of n-heptane. However, there was a significant deviation between model prediction results and experimental data for countercurrent desorption of n-heptane in the presence of toluene. The diffusion of n-heptane is reduced by the presence of toluene, regardless of the relative content of micropores in the intrawall pores, while that of toluene is virtually unaffected by the counter-diffusion of n-heptane. The observed phenomena cannot be addressed by the simple model considering the cross term diffusion effect. The structural property of material and the molecular characteristics of probe molecules were used to account for the difference in the behavior between n-heptane and toluene.  相似文献   
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