Latest ArticlesUncontrolled microglial activation is decisively involved in the neuroinflammatory pathogenesis of brain diseases. Consequently, suppression of microglial overactivation appears to be a strategy for the prevention of nerve injury. In this paper, a novel vanadium complex, vanadyl N-(p-N,N-dimethylaminophenylcarbamoylmethyl)iminodiacetate (VO(p-dmada)), was synthesized from vanadyl sulfate and N,N-dimethyl-p-phenylenediamine, which was structurally characterized by Fourier transform infrared spectrum and ESI-MS analysis. The effect of VO(p-dmada) on neuroinflammation was investigated by using the models of lipopolysaccharide (LPS)-induced BV2 microglial cells and BALB/c mice. Our data demonstrated that VO(p-dmada) significantly suppressed microglial activation by downregulating inflammatory mediators and associated proteins, and inactivating nuclear factor-κB (NF-κB) signaling pathway. VO(p-dmada) also upregulated peroxisome proliferator activated receptor gamma (PPARγ) by reducing transglutaminase 2 and heat shock protein 60 expression. Co-treatment with PPARγ antagonist GW9662 significantly impeded the inhibitory effect of VO(p-dmada) on LPS-induced neuroinflammation. These cumulative findings demonstrated that VO(p-dmada) is a potential new drug for the treatment of neuroinflammation-related neurodegenerative diseases.
The construction of an integrated nanoplatform with controlled fungicide delivery features in the specific microenvironment produced by fungal pathogens is a highly desirable strategy to improve the utilization of fungicides. Herein, we report a supramolecular fungicide delivery system based on benzimidazole-modified NH2-MIL-101(Fe) metal–organic frameworks (B-MIL-101(Fe) MOFs) as carriers loaded with osthole (OS), and β-cyclodextrin (β-CD) as nanovalves to form β-CD@B-MIL-101(Fe)-OS. The nanoplatform can release the loaded OS for fungus control through self-degradation of the MOFs skeleton in an oxalic acid microenvironment produced by Botrytis cinerea. The experimental results exhibit that the constructed supramolecular fungicide delivery system could effectively inhibit mycelial growth and protect the tomatoes from infection by B. cinerea during the ripening stage. This strategy constructs a facile and integrated supramolecular drug delivery system for B. cinerea control and opens up a new avenue for the sustainable development of modern agriculture.
Aromatic compounds such as phenols presented widely in coal chemical industry wastewater (CCW) render the treatment facing great challenge due to their biorefractory characteristics and potential risks to the environment and human health. Ozone-based advanced oxidation processes show promising for these pollutants removal, but the mineralization via ozonation alone is unsatisfactory and not cost-effective. Herein, a hybrid peroxi-coagulation/ozonation process (denoted as PCO) was developed using sacrificial iron plate as an anode and carbon black modified carbon felt as cathode in the presence of ozonation. An enhanced phenol removal of ~100% within 20 min and phenol mineralization of ~80% within 60 min were achieved with a low energy consumption of 0.35 kWh/g TOC. In this novel process, synergistic effect between ozonation and peroxi-coagulation was observed, and beside O3 direct oxidation, peroxone played a dominant role for phenol removal. In the PCO process, the hydrolyzed Fe species enhanced the generation of reactive oxygen species (ROS), while •OH was dominantly responsible for pollutant degradation. This process also illustrated high resistance to high ionic strength and better performance for TOC removal in real wastewater when compared with ozonation and peroxi-coagulation process. Therefore, this process is more cost-effective, being very promising for CCW treatment.
NaClO has been widely used to restore membrane flux in practical membrane cleaning processes, which would induce the formation of toxic halogenated byproducts. In this study, we proposed a novel heat-activated peroxydisulfate (heat/PDS) process to clean the membrane fouling derived from humic acid (HA). The results show that the combination of heat and PDS can achieve almost 100% recovery of permeate flux after soaking the HA-fouled membrane in 1 mmol/L PDS solution at 50 ℃ for 2 h, which is attributed to the changes of HA structure and enhanced detachment of foulants from membranes. The properties of different treated membranes are characterized by scanning electron microscopy (SEM), atomic force microscope (AFM), attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), and X-ray photoelectron spectroscopy (XPS), demonstrating that the reversible and irreversible foulants could be effectively removed by heat/PDS cleaning. The filtration process and fouling mechanism of the cleaned membrane were close to that of the virgin membrane, illustrating the good reusability of the cleaned membrane. Additionally, heat/PDS which can avoid the generation of halogenated byproducts shows comparable performance to NaClO on membrane cleaning and high performance for the removal of fouling caused by sodium alginate (SA), HA-bovine serum albumin (BSA)-SA mixture and algae, further suggesting that heat/PDS would be a potential alternative for membrane cleaning in practical application.
A palladium-catalyzed cascade cyclization of allenylethylene carbonates with 1,3-indandiones was developed, providing biologically interesting tetracyclic dihydrocyclopentaindenofuranone derivatives having three contiguous quaternary carbon centers in moderate to high yields with excellent diastereoselectivities. In this reaction, the allene moiety was fully fused into the cyclopentene ring.
Covalent organic frameworks (COFs) are promising crystalline materials for the light-driven hydrogen evolution reaction (HER) due to their tunable chemical structures and energy band gaps. However, deeply understanding corresponding mechanism is still challenging due to the multiple components and complicated electron transfer and reduction paths involved in photocatalytic HER. Here, the photocatalytic HER investigation has been reported based on three COFs catalysts, 1–3, which are prepared by benzo[1, 2-b: 3, 4-b': 5, 6-b']trithiophene-2, 5, 8-trialdehyde to react with C3 symmetric triamines including tris(4-aminophenyl)amine, 1, 3, 5-tris(4-aminophenyl)benzene, and (1, 3, 5-tris-(4-aminophenyl)triazine, respectively. As the isostructural hexagonal honeycomb-type COF of 2 and 3 reported previously, the crystal structure of 1 has been carefully correlated through the powder X-ray diffraction study with the help of theoretical simulations. 1 shows highly porous framework with Brunauer-Emmett-Teller surface area of 1249 m2/g. Moreover, the introduction of ascorbic acid into the photocatalytic system of COFs achieves the hydrogen evolution rate of 3.75, 12.16 and 20.2 mmol g–1 h–1 for 1–3, respectively. The important role of ascorbic acid in photocatalysis of HER is disclosed to protonate the imine linkages of these COFs, leading to the obvious absorbance red-shift and the improved charge separation efficiency together with reduced resistance in contrast to pristine materials according to the spectroscopic and electronic characterizations. These innovations of chemical and physical properties for these COFs are responsible for their excellent photocatalytic performance. These results elucidate that tiny modifications of COFs structures is able to greatly tune their band structures as well as catalytic properties, therefore providing an available approach for optimizing COFs functionalities.
DNAzyme machines play critical roles in the fields of cell imaging, disease diagnosis, and cancer therapy. However, the applications of DNAzyme machines are limited by the nucleases-induced degradation, non-specific binding of proteins, and insufficient provision of cofactors. Herein, protected DNAzyme machines with different cofactor designs (referred to as ProDs) were nanoengineered by the construction of multifunctional metal-phenolic nanoshells to deactivate the interferential proteins, including nucleases and non-specific binding proteins. Moreover, the nanoshells not only facilitate the cellular internalization of ProDs but provide specific metal ions acting as cofactors of the designed DNAzymes. Cellular imaging results demonstrated that ProDs could effectively and simultaneously monitor multiple tumor-related microRNAs in living cells. This facile and rapid strategy that encapsulates DNAzyme machines into the protective metal-phenolic nanoshells is anticipated to extend to a wide range of functional nucleic acids-based biomedical applications.
Parkinson's disease (PD) is a complex neurological disorder that typically worsens with age. A wide range of pathologies makes PD a very heterogeneous condition, and there are currently no reliable diagnostic tests for this disease. The application of metabolomics to the study of PD has the potential to identify disease biomarkers through the systematic evaluation of metabolites. In this study, urine metabolic profiles of 215 urine samples from 104 PD patients and 111 healthy individuals were assessed based on liquid chromatography-mass spectrometry. The urine metabolic profile was first evaluated with partial least-squares discriminant analysis, and then we integrated the metabolomic data with ensemble machine learning techniques using the voting strategy to achieve better predictive performance. A combination of 8-metabolite predictive panel performed well with an accuracy of over 90.7%. Compared to control subjects, PD patients had higher levels of 3-methoxytyramine, N-acetyl-l-tyrosine, orotic acid, uric acid, vanillic acid, and xanthine, and lower levels of 3, 3-dimethylglutaric acid and imidazolelactic acid in their urine. The multi-metabolite prediction model developed in this study can serve as an initial point for future clinical studies.
Nonfullerene acceptors (NFAs), which usually possess symmetric skeletons, have drawn great attention in recent years due to their pronounced advantages over the fullerene counterparts. Moreover, breaking the symmetry of NFAs could fine tune the molecular dipole, solubility, energy level, intermolecular interaction, molecular packing, crystallinity, etc., and give rise to improved photovoltaic performance. Currently, there are three main strategies for the design of asymmetric NFAs. This review highlights the recent advances of high-performance asymmetric NFAs and briefly outlooks the materials exploration for the future.