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11.
Annette L. West Louise V. Michaelson Elizabeth A. Miles Richard P. Haslam Karen A. Lillycrop Ramona Georgescu Lihua Han Johnathan A. Napier Philip C. Calder Graham C. Burdge 《Lipids》2021,56(2):229-242
The phospholipid composition of lipoproteins is determined by the specificity of hepatic phospholipid biosynthesis. Plasma phospholipid 20:4n-6 and 22:6n-3 concentrations are higher in women than in men. We used this sex difference in a lipidomics analysis of the impact of endocrine factors on the phospholipid class and molecular species composition of fasting plasma from young men and women. Diester species predominated in all lipid classes measured. 20/54 Phosphatidylcholine (PtdCho) species were alkyl ester, 15/48 phosphatidylethanolamine (PtdEtn) species were alkyl ester, and 12/48 PtdEtn species were alkenyl ester. There were no significant differences between sexes in the proportions of alkyl PtdCho species. The proportion of alkyl ester PtdEtn species was greater in women than men, while the proportion of alkenyl ester PtdEtn species was greater in men than women. None of the phosphatidylinositol (PtdIns) or phosphatidylserine (PtdSer) molecular species contained ether-linked fatty acids. The proportion of PtdCho16:0_22:6, and the proportions of PtdEtn O-16:0_20:4 and PtdEtn O-18:2_20:4 were greater in women than men. There were no sex differences in PtdIns and PtdSer molecular species compositions. These findings show that plasma phospholipids can be modified by sex. Such differences in lipoprotein phospholipid composition could contribute to sexual dimorphism in patterns of health and disease. 相似文献
12.
Bokyung Kim Young Ho Ko Massimiliano Runfola Simona Rapposelli Gabriella Ortore Grazia Chiellini Jin Hae Kim 《International journal of molecular sciences》2021,22(7)
Thyromimetics, whose physicochemical characteristics are analog to thyroid hormones (THs) and their derivatives, are promising candidates as novel therapeutics for neurodegenerative and metabolic pathologies. In particular, sobetirome (GC-1), one of the initial halogen-free thyromimetics, and newly synthesized IS25 and TG68, with optimized ADME-Tox profile, have recently attracted attention owing to their superior therapeutic benefits, selectivity, and enhanced permeability. Here, we further explored the functional capabilities of these thyromimetics to inhibit transthyretin (TTR) amyloidosis. TTR is a homotetrameric transporter protein for THs, yet it is also responsible for severe amyloid fibril formation, which is facilitated by tetramer dissociation into non-native monomers. By combining nuclear magnetic resonance (NMR) spectroscopy, computational simulation, and biochemical assays, we found that GC-1 and newly designed diphenyl-methane-based thyromimetics, namely IS25 and TG68, are TTR stabilizers and efficient suppressors of TTR aggregation. Based on these observations, we propose the novel potential of thyromimetics as a multi-functional therapeutic molecule for TTR-related pathologies, including neurodegenerative diseases. 相似文献
13.
Sangmin Lee Biao Che Meiling Tai Wanzhao Li Shin-Hyun Kim 《Advanced functional materials》2021,31(42):2105477
Hydrogel shells that compartmentalize the water core from the aqueous surrounding provide molecular selectivity on size and charge in transmembrane transport. It is highly demanding to produce thin hydrogel shells to minimize diffusion length and maximize core volume. Here, internal osmosis in water-in-oil-in-water-in-oil (W/O/W/O) triple-emulsion droplets is used to produce thin hydrogel shells enclosing a large water core. The triple-emulsion droplets are prepared to have an ultrathin middle oil layer using a capillary microfluidic device. The innermost water droplet has a higher osmolarity than the outer water layer containing photopolymerizable hydrogel precursors, which pumps water from the outer layer to the core through the ultrathin oil layer by the osmosis. Therefore, the outer layer gets thinner and hydrogel precursors are enriched while the size of the triple-emulsion droplets remains unchanged. Through photopolymerization of precursors and phase transfer from oil to water, hydrogel shells enclosing water core are produced in the water environment; the oil layer is ruptured for molecular exchange through the shells. The thickness and composition of the hydrogel shells are precisely controllable by the osmotic conditions. The shells show a high permeation rate due to the thinness as well as controlled cut-off threshold of permeation for neutral and charged molecules. 相似文献
14.
Tallison O. Abreu Roterdan F. Abreu Felipe F. do Carmo Wellington V. de Sousa Helenilson de O. Barros José E.V. de Morais João P.C. do Nascimento Marcelo A.S. da Silva Sergei Trukhanov Alex Trukhanov Larissa Panina Charanjeet Singh Antonio S.B. Sombra 《Ceramics International》2021,47(11):15424-15432
This work presents the dielectric properties of YNbO4 (YNO)–TiO2 composites in the microwave range. X-ray diffraction analysis demonstrates that the addition of TiO2 to YNO results in the formation of a Y(Nb0.5Ti0.5)2O6 phase. In the microwave range, the values of permittivity and dielectric loss did not present major changes with the increment of TiO2. Moreover, the addition of TiO2 results in an improvement in the thermal stability of YNO, with YNO63 demonstrating a resonant frequency of ?8.96 ppm.°C?1. We utilised numerical simulations to evaluate the behaviour of these materials as dielectric resonator antennae and it is found that they exhibit a reflection coefficient below ?10 dB at the resonant frequency, with a realised gain of 4.94 – 5.76 dBi, a bandwidth of 665–1050 MHz and a radiation efficiency above 84%. Our results indicate that YNO–TiO2 composites are interesting candidates for microwave operating devices. 相似文献
15.
Laís D. Silva Fernanda C. Puosso Viviane O. Soares Oscar Peitl Filho Simone do R.F. Sabino Francisco C. Serbena Murilo C. Crovace Edgar D. Zanotto 《Ceramics International》2021,47(13):18720-18731
Bioactive glasses and glass-ceramics (GCs) effectively regenerate bone tissue, however most GCs show improved mechanical properties. In this work, we developed and tested a rarely studied bioactive glass composition (24.4K2O-26.9CaO-46.1SiO2-2.6P2O5 mol%, identified as 45S5-K) with different particle sizes and heating rates to obtain a sintered GC that combines good fracture strength, low elastic modulus, and bioactivity. We analyzed the influence of the sintering processing conditions in the elastic modulus, Vickers microhardness, density, and crystal phase formation in the GC. The best GC shows improved properties compared with its parent glass. This glass achieves a good densification degree with a two-step viscous flow sintering approach and the resulting GC shows as high bioactivity as that of the standard 45S5 Bioglass®. Furthermore, the GC elastic modulus (56 GPa) is relatively low, minimizing stress shielding. Therefore, we unveiled the glass sintering behavior with concurrent crystallization of this complex bioactive glass composition and developed a potential GC for bone regeneration. 相似文献
16.
17.
Romero-Garcés A. Salles De Freitas R. Marfil R. Vicente-Chicote C. Martínez J. Inglés-Romero J. F. Bandera A. 《Multimedia Tools and Applications》2022,81(3):3603-3628
Multimedia Tools and Applications - The design of robots capable of operating autonomously in changing and unstructured environments, requires using complex software architectures in which,... 相似文献
18.
19.
Belcher Calvin H. Zheng Baolong MacDonald Benjamin E. Langlois Eric D. Lehman Benjamin Pearce Charles Delaney Robert Apelian Diran Lavernia Enrique J. Monson Todd C. 《Journal of Materials Science》2022,57(9):5518-5532
Journal of Materials Science - For transformers and inductors to meet the world’s growing demand for electrical power, more efficient soft magnetic materials with high saturation magnetic... 相似文献
20.
Keran Su Kim Huey Ee Jingcan Sun Shao Quan Liu Benjamin Lassabliere Ulrich Feiter Yunle Huang Rui Min Vivian Goh Aileen Pua Bin Yu 《International Journal of Food Science & Technology》2022,57(3):1666-1678
The structural diversity of polyphenols and the inherent limitations of current extraction techniques pose a challenge to extract polyphenols using a simple and green method. Hence, in this study, a method was developed to simultaneously fractionate multiple classes of polyphenols by only varying ethanol-water solutions. Honeybush tea, which is rich in polyphenols, was selected as a model for this study. Solvent extraction followed by solid-phase extraction (SPE) was developed to obtain a polyphenol-rich fraction from six honeybush samples. Based on a gradient elution programme (10%, 30%, 50%, 70% and 90% (v/v) ethanol-water solution) of SPE, the Strata X cartridge showed a better recovery of most targeted polyphenols under 0.9 mL of the drying volume and 1 mL min−1 of the dispensing speed. The elution programme for fractionating most polyphenols was as follows: single elution with 50% ethanol, followed by twice elution with 70% ethanol. The antioxidant capacity was used to analyse the differences among the polyphenol-rich fractions from six honeybush samples. Principal component analysis (PCA) revealed that unfermented C. genistoides (GG) has the greatest antioxidant capacity among the honeybush species studied. Additionally, mangiferin, isomangiferin and vicenin-2 were the main contributors to the antioxidant capacity in six honeybush fractions according to the correlation study. 相似文献