Cytochrome P450 and UDP‐glucosyltransferase (UGT) as phase I and phase II metabolism enzymes, respectively, play vital roles in the breakdown of endobiotics and xenobiotics. Insects can increase the ...expression of detoxification enzymes to cope with the stress from xenobiotics including insecticides. However, the molecular mechanisms for insecticide detoxification in Spodoptera exigua remain elusive, and the genes conferring insecticide metabolisms in this species are less well reported. In this study, 68 P450 and 32 UGT genes were identified. Phylogenetic analysis showed gene expansions in CYP3 and CYP4 clans of P450 genes and UGT33 family of this pest. P450 and UGT genes exhibited specific tissue expression patterns. Insecticide treatments in fat body cells of S. exigua revealed that the expression levels of P450 and UGT genes were significantly influenced by challenges of abamectin, lambda‐cyhalothrin, chlorantraniliprole, metaflumizone and indoxacarb. Multiple genes for detoxification were affected in expression levels after insecticide exposures. The results demonstrated that lambda‐cyhalothrin, chlorantraniliprole, metaflumizone and indoxacarb induced similar responses in the expression of P450 and UGT genes in fat body cells; eight P450 genes and four UGT genes were co‐up‐regulated significantly, and no or only a few CYP/UGT genes were down‐regulated significantly by these four insecticides. However, abamectin triggered a distinct response for P450 and UGT gene expression; more P450 and UGT genes were down‐regulated by abamectin than by the other four compounds. In conclusion, P450 and UGT genes from S. exigua were identified, and different responses to abamectin suggest a different mechanism for insecticide detoxification.
Polymeric g‐C3N4 is a promising visible‐light‐responsive photocatalyst; however, the fast recombination of charge carriers and moderate oxidation ability remarkably restrict its photocatalytic ...oxidation efficiency towards organic pollutants. To overcome these drawbacks, a self‐modification strategy of one‐step formaldehyde‐assisted thermal polycondensation of molten urea to prepare carbon‐deficient and oxygen‐doped g‐C3N4 (VC‐OCN) is developed, and the carbon vacancy concentration is well‐controlled by changing formaldehyde dosage. The VC‐OCN catalysts exhibit interesting carbon vacancy concentration‐dependent photocatalytic removal efficiency to p‐nitrophenol (PNP) and atrazine (ATN), in which VC‐OCN15 with appropriate carbon vacancy concentration displays significantly higher pollutant removal efficiency than bulk g‐C3N4. The apparent first‐order rate constant of VC‐OCN15 for PNP and ATN removal is 4.4 and 5.2 times higher than that of bulk g‐C3N4. A combination of the experimental results and theoretic calculations confirm that the synergetic effect of carbon vacancies and oxygen doping sites can not only delay the recombination of charge carriers but also facilitate adsorption of oxygen molecules on the carbon vacancies, which leads to the generation of plentiful active oxygen species including not only superoxide anion radicals but also indirectly formed hydroxyl radicals and singlet oxygen. These active oxygen species play a dominant role in the removal of target pollutants.
A strategy of one‐step formaldehyde‐assisted thermal polycondensation of molten urea to prepare carbon‐deficient and oxygen‐doped g‐C3N4 (VC‐OCN) is developed, in which carbon vacancy concentration is controllable. At a suitable carbon vacancy concentration, the VC‐OCN exhibits a significantly higher photocatalytic oxidation capacity to organic pollutants than bulk g‐C3N4, attributed to the synergetic effect of carbon vacancies and oxygen doping sites.
A new procedure for the synthesis of aryl methyl sulfides from dimethyl carbonate (DMC) and arylsulfonyl chlorides has been achieved. In this strategy, DMC plays a dual role as both, C1 building ...block and green solvent. Arylsulfonyl chlorides served as the sulfur precursors, and a variety of aryl methyl sulfides were obtained in moderate to excellent yields with good functional group tolerance. Additionally, alkylsulfonyl chloride and dibenzyl carbonate are proven to be suitable substrates as well.
A new procedure for the synthesis of aryl methyl sulfides from dimethyl carbonate (DMC) and arylsulfonyl chlorides has been achieved. In this strategy, DMC plays a dual role as both, C1 building block and green solvent.
This study aimed to investigate the role and underlying mechanism of exosomes secreted by oxidized low-density lipoprotein (oxLDL)-stimulated macrophages in the progression of atherosclerosis (AS).
...Exosomes from peripheral blood of AS patients or oxLDL-treated macrophages were co-cultured with human neutrophils. Neutrophil extracellular traps (NETs) were detected by immunofluorescence staining. The levels of inflammatory cytokines were quantified by enzyme-linked immunosorbent assay (ELISA). The expression levels of miR-146a and superoxide dismutase 2 (SOD2) were determined by quantitative real-time PCR (qRT-PCR) and western blot. The generation of intracellular reactive oxygen species (ROS) was observed by using dichlorofluorescin diacetate (DCFH-DA). ApoE-deficient mice were fed with high-fat diet (HFD) to induce AS. Atherosclerotic plaques were evaluated by Oil red O (ORO) and hematoxylin-eosin (HE) staining.
Our results showed that miRNA-146a was enriched in serum-derived exosomes of AS patients and oxLDL-treated macrophage THP-1-derived exosomes. Importantly, exosomal miR-146a secreted by oxLDL-treated macrophages promoted ROS and NETs release via targeting SOD2. In addition, intravenous administration of oxLDL-treated THP-1 cells-derived exosomes into AS mice significantly deteriorated AS in vivo.
Our findings indicate that exosomal miR-146a derived from oxLDL-treated macrophages promotes NETs formation via inducing oxidative stress, which might provide a novel scientific basis for the understanding of AS progression.
Highlights
The fundamental structure, photophysical and electrical properties of 2D perovskite films were illustrated systematically.
The advantages and challenges of 2D perovskite light-emitting ...diodes (PeLED) have been also discussed, which may benefit the audient to get insight into the 2D perovskite materials as well as the resultant LED devices.
An outlook on further improving the efficiency of pure-blue PeLEDs, enhancing the operational stability of PeLEDs and reducing the toxicity to push this field forward was also provided.
Two-dimensional (2D) perovskites are known as one of the most promising luminescent materials due to their structural diversity and outstanding optoelectronic properties. Compared with 3D perovskites, 2D perovskites have natural quantum well structures, large exciton binding energy (
E
b
) and outstanding thermal stability, which shows great potential in the next-generation displays and solid-state lighting. In this review, the fundamental structure, photophysical and electrical properties of 2D perovskite films were illustrated systematically. Based on the advantages of 2D perovskites, such as special energy funnel process, ultra-fast energy transfer, dense film and low efficiency roll-off, the remarkable achievements of 2D perovskite light-emitting diodes (PeLEDs) are summarized, and exciting challenges of 2D perovskite are also discussed. An outlook on further improving the efficiency of pure-blue PeLEDs, enhancing the operational stability of PeLEDs and reducing the toxicity to push this field forward was also provided. This review provides an overview of the recent developments of 2D perovskite materials and LED applications, and outlining challenges for achieving the high-performance devices.
The cholinergic system in the brain plays crucial roles in regulating sensory and motor functions as well as cognitive behaviors by modulating neuronal activity. Understanding the organization of the ...cholinergic system requires a complete map of cholinergic neurons and their axon arborizations throughout the entire brain at the level of single neurons. Here, we report a comprehensive whole-brain atlas of the cholinergic system originating from various cortical and subcortical regions of the mouse brain. Using genetically labeled cholinergic neurons together with whole-brain reconstruction of optical images at 2-μm resolution, we obtained quantification of the number and soma volume of cholinergic neurons in 22 brain areas. Furthermore, by reconstructing the complete axonal arbors of fluorescently labeled single neurons from a subregion of the basal forebrain at 1-μm resolution, we found that their projections to the forebrain and midbrain showed neuronal subgroups with distinct projection specificity and diverse arbor distribution within the same projection area. These results suggest the existence of distinct subtypes of cholinergic neurons that serve different regulatory functions in the brain and illustrate the usefulness of complete reconstruction of neuronal distribution and axon projections at the mesoscopic level.
A general and efficient protocol based on palladium-catalyzed intramolecular cyclization and reductive aminocarbonylation of iodoarene-tethered propargyl ethers and nitroarenes for the synthesis of ...acetamide-functionalized benzofurans has been explored.
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•A straightforward palladium-catalyzed cyclization/carbonylation reaction of iodoarene-tethered propargyl ethers for the synthesis of acetamides-functionalized benzofurans has been developed.•Nitroarenes has been applied as the nitrogen sources and Mo(CO)6 played a dual role as both CO precursor and reductant.•A variety of acetamides-functionalized benzofurans were prepared in good yields with very good substrate tolerance.
A general and efficient protocol based on palladium-catalyzed intramolecular cyclization and reductive aminocarbonylation reaction for the synthesis of acetamide-functionalized benzofurans has been explored. The reaction using iodoarene-tethered propargyl ethers and nitroarenes as the starting materials. This reaction features the formation of structure defined benzofurans with acetamides as attractive functional groups in a single step operation. By using Mo(CO)6 as both CO source and reductant, a variety of acetamides-functionalized benzofurans were obtained in moderate to good yields with good functional group compatibility.
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•A palladium-catalyzed carbonylative procedure for the synthesis of carboxamide substituted 2-pynones has been explored.•Nitroarenes has been applied as the nitrogen sources and ...Mo(CO)6 played a dual role as both CO precursor and reductant.•A broad range of carboxamide substituted 2-pynones were obtained in moderate to good yields.
A palladium-catalyzed carbonylative synthesis of carboxamide substituted 2-pynones from methyl enynoates and nitroarenes has been developed. With nitroarenes as the nitrogen sources, and Mo(CO)6 as both CO surrogate and reductant, a wide range of carboxamide substituted 2-pynones were obtained in moderate to high yields with quite high functional group compatibility. Moreover, the late-stage modifications of natural molecules was also achieved.
•An improved YOLOv5 network is developed for pavement damage detection from street-view images.•A new Intersection over Union loss function is proposed considering diagonal distance loss.•Fusion of ...the weak feature information of feature layers is enhanced at different spatial scales.•The proposed method was implemented to detect pavement damage throughout the Fengtai District.
Road pavement damage affects driving comfort markedly, threatens driving safety, and may even cause traffic accidents. The traffic management department conventionally captures pavement damage information mainly using manual and vehicle-mounted equipment, which is not conducive to the detection of large-scale road pavement distress. Street-view images can provide full-view images of urban roads where the data is updated regularly by navigation map service companies, making it possible to rapidly detect pavement damage in urban areas. This paper presents a new pavement damage detection approach that is built upon an improved YOLOv5 network and street-view images. The proposed model can deal with a large-scale detection layer to improve the detection precision of large distress targets, achieving thus both cross-layer and cross-scale feature fusion by using the Generalized Feature Pyramid Network (Generalized-FPN) structure. The improved network also involves a diagonal Intersection over Union loss for regression calculation of the boundary box and builds the decoupled Head structure to achieve the decoupling detection of prediction and regression. As a result, the fusion of the weak feature information in feature layers is enhanced at different spatial scales, a more suitable method is achieved for pavement damage detection in the complex context of multi-scale street-view images, and the accuracy of the modified network is much improved in the detection of pavement distress from street-view imagery. Furthermore, We created a large image sample set for model training and testing, and a total of 156,304 street-view images, obtained from Fengtai District, Beijing, China was used for demonstrating the usefulness of the proposed network. The findings indicated that the proposed approach could effectively achieve pavement damage detection of urban roads from street-view images, with a precision average of 79.8% on the test samples. Moreover, the developed model was applied for pavement damage detection for all the roads in Fengtai District, Beijing, indicating that our method can offer viable damage data for road maintenance planning.
AcCHMO, a cyclohexanone monooxygenase from Acinetobacter calcoaceticus, is a typical Type I Baeyer–Villiger monooxygenase (BVMO). We previously obtained the AcCHMOM6 mutant, which oxidizes omeprazole ...sulfide (OPS) to the chiral sulfoxide drug esomeprazole. To further improve the catalytic efficiency of the AcCHMOM6 mutant, a focused mutagenesis strategy was adopted at the intersections of the FAD‐binding domain, NADPH‐binding domain, and α‐helical domain based on structural characteristics of AcCHMO. By using focused mutagenesis and subsequent global evolution two key residues (L55 and P497) at the intersections of the domains were identified. Mutant of L55Y improved catalytic efficiency significantly, whereas the P497S mutant alleviated substrate inhibition remarkably. AcCHMOM7 (L55Y/P497S) was obtained by combining the two mutations, which increased the specific activity from 18.5 (M6) to 108 U/g, and an increase in the Ki of the substrate OPS from 34 to 265 μM. The results indicate that catalytic performance can be elevated by modification of the sensitive sites at the intersection of the domains of AcCHMO. The results also provided some insights for the engineering of other Type I BVMOs or other multidomain proteins.
By using focused mutagenesis and subsequent global evolution, two key residues (L55 and P497) at the intersections of the domains of AcCHMO (a cyclohexanone monooxygenase from Acinetobacter calcoaceticus) were identified. Mutant of L55Y improved catalytic efficiency significantly, whereas the P497S mutant alleviated substrate inhibition remarkably. The results provided some insights for the engineering of other Type I BVMOs or other multidomain proteins.
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