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Extensive exposure to nanomaterials causes oxidative stress and inflammation in various organs and leads to an increased risk of adverse health outcomes; therefore, how to prevent the toxic effects are of great concern to human. Alpha-lipoic acid (ALA) has anti-oxidant and anti-inflammatory activities, suggesting it may be effective to prevent nanomaterial-induced toxicity. However, the results obtained in individual studies remained controversial. We aimed to comprehensively evaluate the effects of ALA supplementation on nanomaterial-induced toxicity by performing a meta-analysis. Databases of PubMed, EMBASE, and Cochrane Library were searched up to May 2022. STATA 15.0 software was used for statistical analysis. Twelve studies were included. Meta-analysis of eight in vivo studies showed ALA supplementation could exert significant effects on nanomaterial-induced oxidative stress (by reducing MDA, ROS and increasing GSH, CAT, GPx, and SOD), inflammation (by downregulating NO, IgG, TNF-α, IL-6, and CRP), apoptosis (by activation of pro-apoptotic caspase-3), DNA damage (by a reduction in the tail length) and organ damage (by a decrease in the liver biomarker ALT and increases in brain neuron biomarker AChE and heart biomarker CPK). Pooled analysis of four in vitro studies indicated ALA intervention increased cell viability, decreased ROS levels, inhibited cell apoptosis and chelated metal ions. Subgroup analyses revealed changing the levels of GSH, IL-6, and metal ions were the main protective mechanisms of ALA supplementation because they were not changed by any subgroup factors. In conclusion, ALA supplementation may represent a potential strategy for the prevention of the toxicity induced by nanomaterials.

BackgroundNanomaterials, widely applied in various fields, are reported to have toxic effects on human beings; thus, preventive or therapeutic measures are urgently needed. Given the anti-inflammatory and antioxidant activities, supplementation with flavonoids that are abundant in the human diet has been suggested as a potential strategy to protect against nanomaterial-induced toxicities. However, the beneficial effects of flavonoids remain inconclusive. In the present study, we performed a meta-analysis to comprehensively explore the roles and mechanisms of flavonoids for animals intoxicated with nanomaterials.MethodsA systematic literature search in PubMed, EMBASE, and Cochrane Library databases was performed up to April 2022. STATA 15.0 software was used for meta-analyses.ResultsA total of 26 studies were identified. The results showed that flavonoid supplementation could significantly increase the levels of antioxidative enzymes (superoxide dismutase, catalase, glutathione, glutathione peroxidase, and glutathione-S-transferase), reduce the production of oxidative agents (malonaldehyde) and pro-inflammatory mediators (tumor necrosis factor-α, interleukin-6, IL-1β, C-reactive protein, immunoglobulin G, nitric oxide, vascular endothelial growth factor, and myeloperoxidase), and alleviate cell apoptosis (manifested by decreases in the mRNA expression levels of pro-apoptotic factors, such as caspase-3, Fas cell surface death receptor, and Bax, and increases in the mRNA expression levels of Bcl2), DNA damage (reductions in tail length and tail DNA%), and nanomaterial-induced injuries of the liver (reduced alanine aminotransferase and aspartate aminotransferase activities), kidney (reduced urea, blood urea nitrogen, creatinine, and uric acid concentration), testis (increased testosterone, sperm motility, 17β-hydroxysteroid dehydrogenase type, and reduced sperm abnormalities), and brain (enhanced acetylcholinesterase activities). Most of the results were not changed by subgroup analyses.ConclusionOur findings suggest that appropriate supplementation of flavonoids may be effective to prevent the occupational detriments resulting from nanomaterial exposure.

The design of high bandgap electrochromic polymers (ECPs) that switch from a high energy absorbing colored state to a near-IR absorbing colorless state requires a challenging balance to be struck between achieving large changes in the absorption profile while maintaining sufficiently low oxidation potentials for use in full-color electrochromic devices. Previous studies on high bandgap ECPs have investigated structure–property relationships in dioxythiophenes copolymerized with various arylenes. Here, we expand this understanding by looking more closely at the effect of the dioxythiophene moiety as well as by varying the substituents on the arylene moiety. Three ECPs have been synthesized to perform this study with repeat units composed of electron-rich dimethoxyphenylene in alternation with dimers of 3,4-dialkoxy- and 3,4-propylenedioxythiophenes, yielding high gap polymers that are vibrant yellow or orange in the charge neutral state. Comparing these newly synthesized polymers to a structurally similar ...

With the advent of the 5G era, the efficient and large-scale preparation of high thermal conductivity materials is viewed as a challenge in the heat conduction and dissipation of electronic components. In this work, poly (diallyl dimethyl ammonium chloride) (PDDA) was used to combine nanodiamond (ND) particles with boron nitride nanosheets (BNNS) by electrostatic interactions. The filler and polyvinyl alcohol (PVA) were mixed to prepare a large-area, flexible, insulating, and high thermal conductivity composite film by the doctor blade method. Considering the high cost of ND, when keeping the filler content at 30 wt%, the introduction of few ND on BNNS (ND/BNNS, 3/100, w/w) enhanced the in-plane thermal conductivity of the composite film from 11.29 to 15.49 W/m·K (pure PVA film~0.22 W/m·K). Given these advantages, this composite film shows promising applications in next-generation portable and flexible electronic devices.

As an essential part of the spacecraft thermal control system, thermal control coatings are widely used. In this paper, nanometer modification technology for spacecraft thermal control coatings is studied. Sol-Gel technology is used to add nano-SiO2 into thermal control coating system, where TEOS is used as the precursor of SiO2, in order to modify the binder and the filler of the coating system. The thermal control coatings were characterized by FTIR, PL and optical properties testing, both before and after proton irradiation, which has a significant applied background in engineering and theoretical research importance. The test results prove that the nano modified coating has well established optical properties (αs ≤ 0.2) and radiation stability. After 90 keV proton irradiation, Δαs of the nano modified coating is reduced to 0.12. The stability improves almost 50 % as compared to ordinary ZnO white paint. The main reason why the performance of nano modified coating degrades is that defects are formed in ZnO during the irradiation, according to the analysis. Modified ZnO powder can effectively eliminate the variations and quantities of irradiation defects, such as oxygen vacancies. This not only improves the proton irradiation stability of ZnO powder, but also effectively reduces the absorbed oxygen content in the coating system, thereby, lowering the damage to chemical bonds in the adhesives.