In this work, we prepared 90 nm thick TiCT-graphene oxide (GO) membranes laminated on a porous support by mixing GO with TiCT. This process was chosen to prevent the penetration of target molecules through inter-edge defects or voids with poor packing. The lattice period of the prepared membrane was 14.28 Å, as being swelled with water, resulting in an effective interlayer spacing of around 5 Å, which corresponds to two layers of water molecules. The composite membranes effectively rejected dye molecules with hydrated radii above 5 Å, as well as positively charged dye molecules, during pressure-driven filtration at 5 bar. Rejection rates were 68% for methyl red, 99.5% for methylene blue, 93.5% for rose Bengal, and 100% for brilliant blue (hydrated radii of 4.87, 5.04, 5.88, and 7.98 Å, respectively). Additionally, the rejections of composite membrane were compared with GO membrane and TiCT membrane.
Tryptophan-derived indole compounds have been widely investigated as antioxidants and as free-radical scavengers. Indole-3-propionic acid (IPA), one of these compounds, is a deamination product of tryptophan. In the present study, we used Mongolian gerbils to investigate IPA's neuroprotective effects against ischemic damage and its antioxidative effects in the hippocampal CA1 region (CA1) after 5 min of transient forebrain ischemia. The repeated oral administration of IPA (10 mg/kg) for 15 days before ischemic surgery protected neurons from ischemic damage. In this group, the percentage of cresyl violet-positive neurons in the CA1 was 56.8% compared with that in the sham group. In the vehicle-treated group, glial fibrillary acidic protein (GFAP)-, S-100-, and vimentin-immunoreactive astrocytes and ionized calcium-binding adapter molecule 1 (Iba-1)- and isolectin B4 (IB4)-immunoreactive microglia were activated 4 days after ischemia/reperfusion, whereas in the IPA-treated ischemic group, GFAP, S-100, Iba-1, and IB4, but not vimentin, immunoreactivity was distinctly lower than that in the vehicle-treated ischemic groups. The administration of IPA significantly decreased the level of 4-hydroxy-2-nonenal, a marker of lipid peroxidation, in ischemic hippocampal homogenates compared with that in the vehicle-treated ischemic groups at various times after ischemia/reperfusion. In addition, immunostaining for 8-hydroxy-2'-deoxyguanosine showed DNA damage in pyramidal neurons in the ischemic CA1 was significantly lower in the IPA-treated ischemic groups than in the vehicle-treated ischemic groups. These results suggest that IPA protects neurons from ischemia-induced neuronal damage by reducing DNA damage and lipid peroxidation.
Melatonin (N-acetyl-5-methoxytryptamine) has multiple functions. In this study, we investigated the effects of melatonin on memory, cell proliferation, and neuroblast differentiation in the dentate gyrus of a mouse model of D-galactose-induced aging. D-galactose was subcutaneously administered to 7-wk-old mice for 10 wk, and age-matched mice were used as controls. Seven weeks after D-galactose administration, vehicle (water) or melatonin (6 mg/L in water) was administered ad libitum to the mice for 3 wk. The administration of D-galactose significantly increased the escape latency compared with that in the control mice on days 1-3. In addition, cells in the subgranular zone and in the granule cell layer of the dentate gyrus showed severe damage (cytoplasmic condensation) in the D-galactose-treated mice. However, melatonin supplementation to these mice for 3 wk significantly ameliorated the D-galactose-induced increase in escape latency and neuronal damage compared with the vehicle-treated group. The administration of melatonin also significantly restored the D-galactose-induced reduction of proliferating cells (Ki67-positive cells) and differentiating neuroblasts (doublecortin-positive neuroblasts) in the dentate gyrus. Furthermore, the administration of melatonin significantly increased Ser133-phosphorylated cyclic AMP response element binding protein in the dentate gyrus. The administration of melatonin significantly reduced D-galactose-induced lipid peroxidation in the dentate gyrus. These results suggest that melatonin may be helpful in reducing age-related phenomena in the brain.
Scandium(III) triflate catalysedFriedel-Crafts alkylation of aromatic compounds with alkenes proceeded readily in the hydrophobic ionic liquid solvents based on 1,3-dialkylimidazolium salts with easy catalyst/solvent recycling, whereas these reactions did not occur in common organic solvents, water or hydrophilic ionic liquids at all.
Here, we have synthesized the new titanium-embedded layered double hydroxides (LDHs), such as (Ni/ Ti)LDH and (Cu/Ti)LDH. First of all, the formation of LDH structures and the bonding nature for a mixed oxide structure of LDHs are explored in this work. Also, it is determined that our LDHs show two absorption bands in the red and blue regions under visible light, thus different from those of a pure titanium oxide with absorption bands in only the UV region. We find that the (Ni/Ti)LDH with the high surface area showed a higher reaction rate, producing 49 mmol O 2 in water oxidation by using 200 mg of the photocatalyst and 1 mmol of AgNO 3 as a sacrificial agent. Also, the (Cu/Ti)LDH showed a good reaction rate and produced 31 mmol of O 2 under the same condition. On the other hand, conventional TiO 2 nanoparticles generated a very small amount of oxygen within the error range under this visible light irradiation. Consequently, these results imply that absorption bands in the visible range and the large surface area of an LDH could result in the high water oxidation photocatalytic activity under visible light.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.