In situ recrystallization of zero-dimensional hybrid metal halide glass-ceramics toward improved scintillation performance.

Zero-dimensional (0D) hybrid metal halide (HMH) glasses are emerging luminescent materials and have gained attention due to their transparent character and ease of processing. However, the weakening of photoluminescence quantum efficiency from crystal to glass phases poses limitations for photonics applications. Here we develop high-performance glass-ceramic (G-C) scintillators via in situ recrystallization from 0D HMH glass counterparts composed of distinct organic cations and inorganic anions. The G-C scintillators maintain excellent transparency and exhibit nearly 10-fold higher light yields and lower detection limits than those of glassy phases. The general in situ recrystallization within the glass component by a facile heat treatment is analyzed via combined experimental elaboration and structural/spectral characterization. Our results on the development of G-Cs can initiate more exploration on the phase transformation engineering in 0D HMHs, and therefore make them highly promising for large-area scintillation screen applications.

Crystal-glass phase transition enabling reversible fluorescence switching in zero-dimensional antimony halides.

Crystal-glass phase transition in luminescent metal halides provides unique opportunities to tune the photoluminescence. Here we report four zero-dimensional Sb-based halide glasses featuring reversible phase transition upon heating and acetone triggering conditions, along with modulated luminescence properties. Benefiting from the fluorescence switching, information encryption and anti-counterfeiting applications are achieved.

1,8-Cineole Alleviates OGD/R-Induced Oxidative Damage and Restores Mitochondrial Function by Promoting the Nrf2 Pathway.

This study examined the effects of 1,8-cineole on reducing oxidative stress injury and restoring mitochondrial function in oxygen-glucose deprivation and reoxygenation (OGD/R) HT22 cells via the nuclear factor erythrocyte 2 related factor 2 (Nrf2) pathway. The optimal concentration of 1,8-cineole to reduce OGD/R injury was screened via cell morphology, cell survival rate, and lactate dehydrogenase (LDH) leakage rate. Oxidative damage was observed by measuring superoxide dismutase (SOD), glutathione peroxidase (GSH-PX), catalase (CAT) activities, and reactive oxygen species (ROS), glutathione (GSH), protein carbonyl, malondialdehyde (MDA), lipid peroxidation (LPO) content, and 8-hydroxy-2 deoxyguanosine (8-OHDG) expression. Mitochondrial function was observed by mitochondrial membrane potential (MMP) and ATPase activity. Nrf2 pathways were observed by the expression levels of total Nrf2, nucleus Nrf2, reduced nicotinamide adenine dinucleotide phosphate (NAD(P)H): quinone oxidoreductase 1 (NQO1) and heme oxygenase-1 (HO-1), the mRNA levels of HO-1 and NQO1. Among different concentrations of 1,8-cineole for promoting HT22 cell proliferation and attenuated OGD/R injury, 10 µmol/L 1,8-cineole was the best. After 1,8-cineole treatment, SOD, GSH-PX, and CAT activities and GSH content increased, while ROS, MDA, LPO, protein carbonyl, and 8-OHDG levels decreased. 1,8-Cineole could restore MMP and increase mitochondrial enzyme activity. It could also increase the total Nrf2, nucleus Nrf2, NQO1, and HO-1, and Nrf2 inhibitor brusatol reduced the effect of 1,8-cineole. Immunofluorescence assay showed that 1,8-cineole could facilitate the transfer of Nrf2 into the nucleus. 1,8-cineole increased the mRNA levels of NQO1 and HO-1. The above results showed that 1,8-cineole could alleviate OGD/R-induced oxidative damage and restores mitochondrial function by activating the Nrf2 signal pathway.

Buyang Huanwu decoction alleviates oxidative injury of cerebral ischemia-reperfusion through PKCε/Nrf2 signaling pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Ischemic stroke is a significant risk factor for human health, and Buyang Huanwu Decoction is a classical and famous Chinese formula for treating it, but without clear pharmacological mechanism. AIM OF THE STUDY: The aim of this study was to investigate that the molecular mechanism of BYHWD activation of the PKCε/Nrf2 signaling pathway to attenuate cerebral ischemia-reperfusion (I/R) oxidative damage. MATERIALS AND METHODS: The MCAO method was used to establish a brain I/R injury model in SD rats, and neurological deficits were evaluated by neurological function score. Neuronal damage was observed by Nissl staining and immunofluorescence detection of MAP2 expression. Oxidative damage was observed by ROS, SOD, GSH-PX, MDA, and 8-OHdG. Changes in mitochondrial membrane potential were detected by using the fluorescent probe JC-1. The Western blot analysis detected protein expression of PKCε, P-PKCε, total Nrf2, nuclear Nrf2, HO-1, and NQO1. RESULTS: BYHWD significantly enhanced neural function, reduced neuronal damage, inhibited the production of ROS, decreased MDA and 8-OHdG levels, increased SOD and GSH-PX activity to reduce oxidative damage, and restored mitochondrial membrane potential. BYHWD and Nrf2 activator TBHQ increased total Nrf2, nucleus Nrf2 protein expression, and its downstream HO-1 and NQO1 proteins, and the administration of the Nrf2 inhibitor brusatol reduced the enhancing effect of BYHWD. Meanwhile, BYHWD increased the expression of PKCε and P-PKCε and the administration of the PKCε inhibitor εV1-2 reduced the effect of BYHWD in increasing the expression of PKCε, P-PKCε, nuclear Nrf2, and HO-1, as well as promoting the effect of Nrf2 translocation to the nucleus. CONCLUSION: This study marks the first to demonstrate that BYHWD ameliorates oxidative damage and attenuates brain I/R injury by activating the PKCε/Nrf2/HO-1 pathway.

Sequential and Reversible Phase Transformations in Zero-Dimensional Organic-Inorganic Hybrid Sb-based Halides towards Multiple Emissions.

Zero-dimensional (0D) metal halides have drawn increasing attention due to the attractive structure dependent photoluminescence (PL) properties. Here, we report two new 0D organic-inorganic hybrid Sb-based halides, (MTP)6 SbBr6 Sb2 Br9 ⋅H2 O (MTP=Methyltriphenylphosphonium, crystal 1) and (MTP)2 SbBr5 (crystal 2), featuring a reversible structural phase transformation and tunable orange and red emissions upon dehydration and rehydration of H2 O molecules. Intriguingly, a subsequent heat treatment further enables the formation of glassy state (MTP)2 SbBr5 (glass 3) with near-infrared luminescence, moreover, a sequential reverse phase transformation from glass 3 to crystal 2 and 1 is triggered by acetonitrile and water vapor stepwise. The anti-counterfeiting demo based on the tunable and reversible PL switching is finally achieved and thus the phase structure engineering in 0D metal halides expands their multiple applications in optical fields.

Kinetics of inhibitory effect of isoferulic acid on mushroom tyrosinase.

A study on the kinetics of inhibitory effect of isoferulic acid on the monophenolase and diphenolase activity of mushroom tyrosinase was carried out using enzymological kinetic analysis method in a Na2HPO4-NaH2PO4 buffer solution (pH = 6.8) at 30°C. It was found that isoferulic acid efficiently inhibits both monophenolase and diphenolase activities of mushroom tyrosinase under experimental conditions. Concentrations of isoferulic acid leading to 50% rate inhibition (IC50) on monophenolase and diphenolase activity were calculated to be 0.13 mmol/L and 0.39 mmol/L, respectively, which are much lower than that of arbutin (IC50 = 5.3 mmol/L for diphenolase activity). The presence of isoferulic acid also prolongs the lag period in the oxidation process of l-tyrosine via tyrosinase-a 4.3-min lagging was observed with the presence of 0.20 mmol/L isoferulic acid-compared to a 1.1-min lagging in the absence of isoferulic acid. The Lineweaver-Burk plot demonstrates a competitive behavior of isoferulic acid in the tyrosinase oxidation of l-3,4-dihydroxyphenylalanine, with maximum reaction rate (vm) and inhibition constant (KI) at 64.5 µM/min and 0.11 mmol/L, respectively.