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161.
Human skin aging is affected by various biological signaling pathways, microenvironment factors and epigenetic regulations. With the increasing demand for cosmetics and pharmaceuticals to prevent or reverse skin aging year by year, designing multiple-molecule drugs for mitigating skin aging is indispensable. In this study, we developed strategies for systems medicine design based on systems biology methods and deep neural networks. We constructed the candidate genomewide genetic and epigenetic network (GWGEN) via big database mining. After doing systems modeling and applying system identification, system order detection and principle network projection methods with real time-profile microarray data, we could obtain core signaling pathways and identify essential biomarkers based on the skin aging molecular progression mechanisms. Afterwards, we trained a deep neural network of drug–target interaction in advance and applied it to predict the potential candidate drugs based on our identified biomarkers. To narrow down the candidate drugs, we designed two filters considering drug regulation ability and drug sensitivity. With the proposed systems medicine design procedure, we not only shed the light on the skin aging molecular progression mechanisms but also suggested two multiple-molecule drugs for mitigating human skin aging from young adulthood to middle age and middle age to old age, respectively. 相似文献
162.
Andrzej Günther Edyta Makuch Anna Nowak Wiktoria Duchnik ukasz Kucharski Robert Peech Adam Klimowicz 《Molecules (Basel, Switzerland)》2021,26(11)
This study investigated the antioxidant activity DPPH, ABTS, and Folin–Ciocalteu methods of betulin (compound 1) and its derivatives (compounds 2–11). Skin permeability and accumulation associated with compounds 1 and 8 were also examined. Identification of the obtained products (compound 2–11) and betulin isolated from plant material was based on the analysis of 1H- NMR and 13C-NMR spectra. The partition coefficient was calculated to determine the lipophilicity of all compounds. In the next stage, the penetration through pig skin and its accumulation in the skin were evaluated of ethanol vehicles containing compound 8 (at a concentration of 0.226 mmol/dm3), which was characterized by the highest antioxidant activity. For comparison, penetration studies of betulin itself were also carried out. Poor solubility and the bioavailability of pure compounds are major constraints in combination therapy. However, we observed that the ethanol vehicle was an enhancer of skin permeation for both the initial betulin and compound 8. The betulin 8 derivative showed increased permeability through biological membranes compared to the parent betulin. The paper presents the transformation of polycyclic compounds to produce novel derivatives with marked antioxidant activities and as valuable intermediates for the pharmaceutical industry. Moreover, the compounds contained in the vehicles, due to their mechanism of action, can have a beneficial effect on the balance between oxidants and antioxidants in the body, minimizing the effects of oxidative stress. The results of this work may contribute to knowledge regarding vehicles with antioxidant potential. The use of vehicles for this type of research is therefore justified. 相似文献
163.
164.
《Macromolecular bioscience》2017,17(5)
The development of chronic wounds has been frequently associated with alkaline pH values. The application of pH‐modulating wound dressings can, therefore, be a promising treatment option to promote normal wound healing. This study reports on the development and characterization of acidic hydrogel dressings based on interpenetrating poly(ethylene glycol) diacrylate/acrylic acid/alginate networks. The incorporation of ionizable carboxylic acid groups results in high liquid uptake up to 500%. The combination of two separate polymer networks significantly improves the tensile and compressive stability. In a 2D cell migration assay, the application of hydrogels (0% to 1.5% acrylic acid) results in complete “wound” closure; hydrogels with 0.25% acrylic acid significantly increase the cell migration velocity to 19.8 ± 1.9 µm h−1. The most promising formulation (hydrogels with 0.25% acrylic acid) is tested on 3D human skin constructs, increasing keratinocyte ingrowth into the wound by 164%.
165.
M. Šimková 《Isotopes in environmental and health studies》2013,49(6):207-210
A methed was elaborated to determine arsenic amount in skin samples by neutron activation analysis and high-resolution gamma spectrometry including sample preparation after mineralization by sorption on silicagel saturated with phosphoantimonic acid. The samples were irradiated in the VVR-S reactor core in a flux of 1013 neutrons · cm?2 · s?1, mineralized with a mixture of nitric and sulphuric acids, the gamma spectrum was measured after passing through an ion-exchanger containing 0.5 mol P2O5 to 1 mol Sb2O5 (SP-2) by a gamma-spectroscopy system PLURIMAT 20 with a Ge(Li) detector, and the 76As photopeak of Eγ = 0.559 MeV was measured. The values of the results obtained varied in the range of (4?5 )× 10?1 ppm arsenic. The sensitivity of the proposed determination method is l×10?3 μg arsenic. 相似文献
166.
167.
Pressurized hot water extraction (PHWE) was employed to prepare extracts from dried grape skin of two wine grape varieties (St. Laurent and Alibernet) at various temperatures (from 40 up to 120 °C) and amounts of sample (0.5, 1.0 and 1.5 g). To assess the antioxidant activity of the extracts, electron paramagnetic resonance (EPR) spectroscopy was applied involving DPPH and ABTS+ assays. Other extract characteristics including HPLC profile of anthocyanins and total phenolic compound content were obtained as well. PHWE has also been compared with earlier results of extractions of the same grape skin samples with compressed methanol and compressed ethanol under the conditions of pressurized fluid extraction (PFE). From this comparison, PHWE emerges as the more benign and efficient extraction method to recover valuable phenolic antioxidants from grape skins for the prospective use in functional food supplements. 相似文献
168.
《Physics and Chemistry of Liquids》2012,50(1):95-102
Abstract The two-dimensional boundary layer equations for a class of non-Newtonian fluids, for which the apparent viscosity can be expressed as a polynomial in the second scalar invariant of the rate of strain tensor, have been derived. These equations have been employed to analyse the flow near a stagnation point over a stationary impermeable wall. The non-Newtonian effects on the boundary layer velocity profile and the wall skin friction have been studied, and compared with the corresponding Newtonian fluid. The fluid velocity in the boundary layer has been shown to be retarded by the non-Newtonian effect while the skin friction increases proportionate to it. 相似文献
169.
《Analytical letters》2012,45(5):776-785
To obtain maximum non-anthocyanin phenolics from grape skins, various extraction conditions were evaluated according to the amounts of 8 non-anthocyanin phenolics. The result showed that the optimal extraction was performed in ethyl acetate solution at 25°C, with liquid/solid ratio of 10:1 (ml/g) and for 30 min. On this basis, the non-anthocyanin extracts from two red and two white grape cultivars were analyzed using high performance liquid chromatography coupled with tandem mass spectrometry (HPLC- MS/MS), and twenty-four compounds were qualified and simultaneously quantified, which indicated that the present extraction method was suitable for the study of non-anthocyanin in grape skins. 相似文献
170.
Amir Salati Hamid Keshvari Akbar Karkhaneh Shahrouz Taranejoo 《Journal of Macromolecular Science: Physics》2013,52(10):1972-1982
Acrylic acid (AAc) was grafted onto the surfaces of polydimethylsiloxane (PDMS) films using a two-step oxygen plasma treatment. The first step of this method included oxygen plasma pretreatment of the PDMS films, immersion in AAc, and drying. The second step was carried out by plasma polymerization of the preadsorbed reactive AAc on the surfaces of the dried pretreated films. Then chitosan and gelatin were immobilized onto the poly(acrylic acid) grafted silicone through covalent bonding. The films were characterized by attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy and water contact angle measurements. Fibroblast cells (L929) were cultured onto the chitosan- and gelatin-immobilized poly(acrylic acid)-grafted silicone and poly(acrylic acid)-grafted silicone films. It was observed that the chitosan- and gelatin-immobilized surfaces showed significant cell growth in comparison with poly(acrylic acid)-grafted silicone samples. It seems that chitosan- and gelatin-immobilized surfaces may have an excellent potential to be used as a derm-like matrix. 相似文献