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The dyshomeostasis of transition metal ions, accumulation of amyloid-β (Aβ) senile plaques and neuroinflammatory response found in the brain of patients with Alzheimer's disease (AD) have been suggested to be involved in AD pathogenesis. Novel compounds capable of targeting metal-Aβ species and neuroinflammation would be valuable. AD-35 is such a patented small-molecule compound derived from innovative modification of the chemical structure of donepezil. This compound could moderately inhibit acetylcholinesterase and metal-induced Aβ aggregation in vitro and showed disassembly of Aβ aggregates. The effects of AD-35 on cognitive impairments and neuroinflammatory changes caused by intracerebroventricular injection of Aβ25-35 were studied in rats. Compared to sham group, Aβ25-35 injection significantly led to learning and memory deficits, astrocyte activation, and pro-inflammatory cytokines releases (TNF-α and IL-1β). Further studies indicated that the phosphorylation of extracellular signal-regulated kinase was involved in astrocyte activation and pro-inflammatory cytokines production. Oral administration of AD-35 could markedly attenuate Aβ25-35 injection-induced astrocyte activation, pro-inflammatory cytokines TNF-α and IL-1β release, and memory deficits. On the contrary, donepezil only showed inhibition of IL-1β production, but failed to block astrocyte activation and TNF-α production. These results showed that AD-35 would be a novel multi-mechanism drug for the prevention and/or treatment of AD. [ABSTRACT FROM AUTHOR]

Aluminum is abundant, low in cost, compatible with complementary metal-oxide semiconductor manufacturing methods, and capable of supporting tunable plasmon resonance structures that span the entire visible spectrum. However, the use of Al for color displays has been limited by its intrinsically broad spectral features. Here we show that vivid, highly polarized, and broadly tunable color pixels can be produced from periodic patterns of oriented Al nanorods. Whereas the nanorod longitudinal plasmon resonance is largely responsible for pixel color, far-field diffractive coupling is used to narrow the plasmon linewidth, enabling monochromatic coloration and significantly enhancing the far-field scattering intensity of the individual nanorod elements. The bright coloration can be observed with p-polarized white light excitation, consistent with the use of this approach in display devices. The resulting color pixels are constructed with a simple design, are compatible with scalable fabrication methods, and provide contrast ratios exceeding 100:1. [ABSTRACT FROM AUTHOR]

Our previous analyses showed that allopregnanolone (APα) significantly increased proliferation of rodent and human neural progenitor cells in vitro. In this study, we investigated the efficacy of APα to promote neurogenesis in the hippocampal subgranular zone (SGZ). to reverse learning and memory deficits in 3-month-old male triple transgenic mouse model of Alzheimer's (3xTgAD) and the correlation between APα-induced neural progenitor cell survival and memory function in 3xTgAD mice. Neural progenitor cell proliferation was determined by unbiased stereological analysis of BrdU incorporation and survival determined by FACS for BrdU+ cells. Learning and memory function was assessed using the hippocampal-dependent trace eye-blink conditioning paradigm. At 3 months, basal level of BrdU+ cells in the SGZ of 3xT9AD mice was significantly lower relative to non-Tg mice, despite the lack of evident AD pathology. APα significantly increased, in a dose-dependent manner, BrdU+ cells in SGZ in 3xTgAD mice and restored SGZ proliferation to normal magnitude. As with the deficit in proliferation. 3xTgAD mice exhibited deficits in learning and memory. APα reversed the cognitive deficits to restore learning and memory performance to the level of normal non-Tg mice. In 3xTgAD mice, APα-induced survival of neural progenitors was significantly correlated with APα-induced memory performance. These findings suggest that early neurogenic deficits, which were evident before immunodetectable Aβ, may contribute to the cognitive phenotype of AD, and that APα could serve as a regenerative therapeutic to prevent or delay neurogenic and cognitive deficits associated with mild cognitive impairment and Alzheimer's disease. [ABSTRACT FROM AUTHOR]

Hepatitis C virus (HCV) induces microtubule aggregates in infected hepatocytes. To determine if cytoskeletal elements are important for HCV RNA synthesis, we examined the effect of cytoskeleton inhibitors on HCV replicon transcription in Huh7 cells. The data demonstrate that HCV replication complex-mediated RNA synthesis requires microtubule and actin polymerization. [ABSTRACT FROM AUTHOR]

Here, we propose to modify the hydrophilicity of metal-organic framework (MOF) particles by an interfacial assembling route, which is based on the surface-active nature of MOF particles. It was found that hydrophilic UiO-66-NH2 particles can be converted to hydrophobic particles through an oil-water interfacial assembling route. The underlying mechanism for the conversion of UiO-66-NH2 was investigated by X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy. It was revealed that the close assembly of UiO-66-NH2 particles at the oil-water interface strengthens the coordination between organic ligands and metal ions, which results in a decrease in the proportion of hydrophilic groups on UiO-66-NH2 particle surfaces. Hydrophobic UiO-66-NH2 particles show improved adsorption capacity for dyes in organic solvents compared with pristine UiO-66-NH2 particles. It is expected that the interfacial assembling route can be applied to the synthesis of different kinds of MOF materials with tunable hydrophilicity or hydrophobicity required for diverse applications. [ABSTRACT FROM AUTHOR]

Wedemonstrate the facile synthesis of high purity aluminumnanocrystals over a range of controlled sizes from 70 to 220 nm diameterwith size control achieved through a simple modification of solventratios in the reaction solution. The monodisperse, icosahedral, andtrigonal bipyramidal nanocrystals are air-stable for weeks, due tothe formation of a 2–4 nm thick passivating oxide layer ontheir surfaces. We show that the nanocrystals support size-dependentultraviolet and visible plasmon modes, providing a far more sustainablealternative to gold and silver nanoparticles currently in widespreaduse. [ABSTRACT FROM AUTHOR]

Two compounds La1/3MO3 (M = Nb, Ta) with A-site deficient perovskite-type structure were synthesized by the solid state reaction method. The photocatalytic properties of these compounds were characterized by H2 evolution with Pt cocatalyst from CH3OH/H2O solution and by O2 evolution from AgNO3 aqueous solution under UV light irradiation. The results showed that the average rate of H2 evolution was about 61.07 μmol h-1 for La1/3NbO3 and 95.79 μmol h-1 for La1/3TaO3 after 24 hours of reaction time, while the initial rate of O2 evolution was 26.31 μmol h-1 for La1/3NbO3 and 16.21 μmol h-1 for La1/3TaO3, respectively. H2 evolution was also observed over La1/3MO3 (M = Nb, Ta) with NiO cocatalyst from pure water under UV light irradiation. [ABSTRACT FROM AUTHOR]

A WO3/TiO2composite is constructed with the ability to degrade organic molecules under visible irradiation, which is newly explored by UV pre-irradiation. The long lasting visible-light photoactivity and the consecutive photocatalytic process will benefit the efficient use of solar energy. [ABSTRACT FROM AUTHOR]