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T-2 is one of the most toxic type A trichothecene mycotoxins produced by several fusarium species, which causes a deep harm to the immune system, liver, kidney and brain cells. It is widely found in cereals, cereal products and animal feed. Consequently, it is very important to establish a rapid, efficient and low-cost method for detecting T-2 toxin. In this study, a time-resolved fluorescent immunotomography (TRFIA) paper-based sensor was established. Sheep anti-mouse IgG can protect monoclonal antibody and amplify fluorescence signal. Polystyrene fluorescent microspheres were combined with sheep anti-mouse IgG to prepare fluorescent probes (IgG@Eu). During the detection process, the target-specific monoclonal antibody binds to fluorescence probe (IgG@Eu) to form a complex (mAb-IgG@Eu), which is then captured by the target substance and fixed on the C line. The uncaptured complex (mAb-IgG@Eu) is fixed on the T line by the original coating. Monoclonal antibody can protect its activity by indirect binding with Eu fluorescent beads (FBS). This labeling method improved the binding ratio between the fluorescent microspheres and the monoclonal antibodies. The results of the test strip were compared with liquid chromatography–mass spectrometry (LC–MS/MS), and showed low test line and high recovery rate. With the outstanding augment response, the limit of detection reached 0.01 ng/mL and a wide linear range from 0.0625 to 50 ng/mL was presented. Experimental results show that the detection limit was 0.052 ng/mL and 0.071 ng/mL in corn substrate and feed substrate. The recoveries were between 95.31 and 119.03%, and the relative standard deviations were less than 6.02%. The method was verified by LC–MS/MS, and the results showed that the method had good accuracy.

Protein tyrosine phosphatase 1B (PTP1B) is a member of the phosphotyrosine phosphatase family and plays an important role in the signal transduction of diabetes. Inhibition of PTP1B activity can increase insulin sensitivity and reduce blood sugar levels. Therefore, it is urgent to find compounds with novel structures that can inhibit PTP1B. This study designed imidazolidine-2,4-dione derivatives through the computer-aided drug design (CADD) strategy, and the Comp#10 showed outstanding inhibitory ability. (IC50 = 2.07 μM) and selectivity. The inhibitory mechanism at molecular level of Comp#10 on PTP1B was studied by molecular dynamics simulation. The results show that the catalytic region of PTP1B protein is more stable, which makes the catalytic sites unsuitable for exposure. Interestingly, the most obvious changes in the interaction between residues in the P-loop region (such as: His214, Cys215, and Ser216). In short, this study reported for the first time that imidazolidine-2,4-dione derivatives as novel PTP1B inhibitors had good inhibitory activity and selectivity, providing new ideas for the development of small molecule PTP1B inhibitors.

Air pollutant accumulations during wintertime persistent cold air pool (PCAP) events in mountain valleys are of great concern for public health worldwide. Uncertainties associated with the simulated meteorology under stable conditions over complex terrain hinder realistic simulations of air quality using chemical transport models. We use the Community Multiscale Air Quality (CMAQ) model to simulate the gaseous and particulate species for one-month in January 2011 during the Persistent Cold Air Pool Study (PCAPS) in the Salt Lake Valley (SLV), Utah (USA). Results indicate that the temporal variability associated with the elevated NO(x) and PM(2.5) concentrations during PCAP events were captured by the model (r=0.20 for NO(x) and r=0.49 for PM(2.5)). However, concentrations were not at the correct magnitude (NMB= −35%/12% for PM(2.5) during PCAPs/non-PCAPs) where PM(2.5) was underestimated during PCAP events and overestimated during non-PCAP periods. The underestimated PCAP strength is represented by valley heat deficit, which contributed to the underestimated PM(2.5) concentrations compared with observations due to the model simulating more vertical mixing and less stable stratification than what was observed. Based on observations, the dominant PM(2.5) species were ammonium and nitrate. We provide a discussion that aims to investigate the emissions and chemistry model uncertainties using the nitrogen ratio method and the thermodynamic ammonium nitrate regime method.

Organic molecule/half-metallic oxide interfaces play essential roles in recent molecular spintronics devices, yet factors governing the spin polarization of the hybridized interface state (HIS) formed there remain unclear because of the lack of direct spectroscopic evidence for it. Here, we present a spin-polarized metastable deexcitation spectroscopy (SPMDS) experiment, which is sensitive to the topmost surface, showing that the adsorption of pyridine on H-terminated Fe3O4(100) at 100 K produces a highly spin-polarized HIS, while no such HIS forms on a bare Fe3O4(100) surface. A density functional theory calculation has predicted the formation of half-metallic HIS, which is consistent with the SPMDS results. This can be understood on the basis of the interface chemical bonding formed by the coordination of the nitrogen end of pyridine to the surface Fe atom where half-metallic conduction electrons are distributed.

Hsa-miR-599 was identified as a tumor suppressor against cancer. This study aimed to explore possible mechanisms of antitumor effect of hsa-miR-599 against breast cancer. Tissue specimens were collected from 106 breast cancer cases, and breast cancer cell line MCF-7 was cultured for in vitro experiments. The expression pattern of hsa-miR-599 was measured via quantitative real-time polymerase chain reaction. Lipofectamine® 2000 reagent was used for cell transfection. Cell viability, motility and apoptosis were detected using MTT assay, transwell assay, and flow cytometer, respectively. Protein analysis was performed via western blot. Hsa-miR-599 expression was decreased in breast cancer tissues and cells. Moreover, its expression was negatively correlated with TNM stage (p = 0.004) and lymph node metastasis (p = 0.001). Enhanced hsa-miR-599 expression in breast cancer cells could induce the inhibition against cell proliferation, migration and invasion, and strengthen cell apoptosis. BRD4 might be a target of hsa-miR-599. Hsa-miR-599 combined with BRD4 inhibited breast cancer progression through targeting Jagged1/Notch1 pathway. Hsa-miR-599 expression is downregulated in breast cancer. Hsa-miR-599 may inactivate BRD4/Jagged1/Notch1 axis, thus suppressing malignant progression of breast cancer.

Salt stress significantly induces accumulation of misfolded or unfolded proteins in plants. Endoplasmic reticulum (ER)-associated protein degradation (ERAD) and other degradative machineries function in the degradation of these abnormal proteins, leading to enhanced salt tolerance in plants. Here we characterise that a novel receptor-like kinase, Salt-Induced Malectin-like domain-containing Protein1 (SIMP1), elevates ERAD efficiency during salt stress through UMP1A, a putative proteasome maturation factor in Arabidopsis. SIMP1 loss-of-function caused a salt-hypersensitive phenotype. SIMP1 interacts and phosphorylates UMP1A, and the protein stability of UMP1A is positively regulated by SIMP1. SIMP1 modulates the 26S proteasome maturation possibly through enhancing the recruitment of specific β subunits of the core catalytic particle to UMP1A. Functionally, the SIMP1-UMP1A module plays a positive role in ERAD efficiency in Arabidopsis. The degradation of misfolded/unfolded proteins was impaired in both simp1 and ump1a mutants during salt stress. Consistently, both simp1 and ump1a plants exhibited reduced ER stress tolerance. Phenotypic analysis revealed that SIMP1 regulates salt tolerance through UMP1A at least in part. Taken together, our work demonstrated that SIMP1 modulates plant salt tolerance by promoting proteasome maturation via UMP1A, therefore mitigating ER stress through enhanced ERAD efficiency under saline conditions.

Low-power consumption and high sensitivity are highly desirable for a vast range of NH3 sensing applications. As a new type of two-dimension (2D) material, Ti3C2Tx is extensively studied for room temperature NH3 sensors recently. However, the Ti3C2Tx MXene based gas sensors suffer mainly from low sensitivity. Herein, we report a sensitive Ti3C2Tx/WO3 composite resistive sensor for NH3 detection. The Ti3C2Tx/WO3 composite consisting of WO3 nanoparticles anchored on Ti3C2Tx nanoflakes were synthesized successfully with a facile ultra-sonication technique. The composite sensor with optimized components exhibits a high sensitivity of 22.3% for 1 ppm NH3 at room temperature, which is 15.4 times higher than the pure Ti3C2Tx sensor. Furthermore, the composite sensor has excellent reproducibility, good long-term stability, and high selectivity to NH3. The relative humidity influence on NH3 gas sensing properties of the sensors was systematically studied. This research provides an efficient route for the preparation of novel MXene-based sensitive materials for high-performance NH3 sensors.

The development of low power consumption sensing devices for detecting trace toxic gases is imperative for a wide variety of applications. Recently, hybrid organic–inorganic lead perovskite-based sensors have been fabricated to demonstrate their potential for gas sensing application. However, the poor repeatability and toxicity of lead halide perovskites severely restrict their further practical applications. Here, the lead-free all-inorganic cesium copper iodide (CsCu2I3) perovskite nanostructured networks are deposited onto interdigital electrodes patterned substrate as the gas sensitive layer via simply spin coating the precursors. The sensor exhibites excellent room temperature NO2 sensing properties, including ultra-low limit of detection, excellent repeatability, and good selectivity. Dynamic testing displays the good cycling repeatability of the sensor for ppb level NO2. The ultra-sensitive NO2 sensing behavior of the CsCu2I3 nanostructure networks are mainly attributed to the unique nanoneedle clusters network structure and large amount of cation vacancies on the perovskite surface. In conclusion, the high sensitivity and environmentally friendly CsCu2I3 sensor shows great potential for trace indoor pollutants detection and breathe analysis for disease diagnosis.

Due to the expansion of human production activities, toxic ammonia (NH3) is excessively released into the atmosphere, being a huge threat to human health and the natural environment. Therefore, it is of great significance to design an easy-synthesized gas-sensing material with both good room temperature sensitivity and selectivity for trace-level NH3 detection. Herein, we fabricate a chemiresistive NH3 gas sensor with enhanced performance based on Ni(OH)2/Ti3C2Tx hybrid materials. The Ni(OH)2/Ti3C2Tx hybrid materials are synthesized by an in-situ electrostatic self-assembly method. Attributed to the formation of interfacial heterojunctions and the modulation of carrier density, the Ni(OH)2/Ti3C2Tx hybrid sensor exhibits high response, outstanding repeatability, good selectivity and stability in low concentrations of NH3. Moreover, the Ni(OH)2/Ti3C2Tx hybrid sensor has a higher response to 10 ppm NH3 at the relative humidity of 40% and 60%, which makes it promising for applications in real complex environments with high humidity. Benefitting from the low power consumption and easy fabrication process, the Ni(OH)2/Ti3C2Tx hybrid sensor possesses a broad application prospect in the internet of things (IoT) environmental monitoring.

In this work, a dual-labeled multiple aptasensor that can simultaneously detect multiple antibiotics was constructed, with kanamycin (KAN) and tobramycin (TOB) used as the model analytes. The aptasensor reported here featured three key elements, namely the RNA-based aptamer strands, semiconductor quantum dots (QDs), and gold nanoshells (AuNSs). Due to the high-affinity pairing between streptavidin (SA) and biotin (Bio), the two biotinylated aptamers (kanamycin aptamer, KAP; tobramycin aptamer, TAP) responsible for the specific recognition of KAN and TOB were conjugated to SA-coated cadmium sulfide (CdS) and lead sulfide (PbS) QDs, respectively for the syntheses of KAP-Bio-SA-CdS and TAP-Bio-SA-PdS composites. Moreover, the AuNSs had a very high loading efficiency for the as-prepared two composites on the gold electrode surface due to their outstanding surface-area-to-volume ratio. In the presence of target antibiotics, CdS and PbS QDs were released from AuNSs followed by dissolution into their respective metal ions for stripping analysis by differential pulse voltammetry (DPV). As a result, intensified signals from DPV peaks were obtained due to the large amount of the metal ion labels dissolved in the solution. The devised aptasensor exhibited wider detection linear range (KAN, 1–4 × 102 nM; TOB, 1–1 × 104 nM) and lower detection limits (KAN, 0.12 nM; TOB, 0.49 nM) compared to the previously reported sensors. Furthermore, the detection of KAN and TOB spiked in milk samples was successfully demonstrated. Therefore, the proposed aptasensor provides a novel sensitive platform for multi-antibiotics detection.

Chiral α-substituted 1,3-dihydroisobenzofurans are key scaffolds in a number of bioactive natural products and synthetic pharmaceuticals. However, catalytic asymmetric approaches have been rarely developed. Here, a redox deracemization technology is adopted to address the catalytic asymmetric synthesis. A broad range of α-aryl substituted 1,3-dihydroisobenzofurans are effectively deracemized in high efficiency with excellent ee. α-Alkynyl substituted ethers were also compatible with the deracemization technology.

Plants produce reactive oxygen species (ROS) to defend pathogens. To counteract this attack, certain pathogens express superoxide dismutases (SODs) to scavenge host-derived ROS. However, the roles of SODs in Verticillium dahliae, an important vascular pathogen, are not clear. Our previous study has shown that a putative extracellular SOD (VdSOD5) of V. dahliae is significantly induced by culturing in cotton tissues, suggesting that VdSOD5 may play an important role in host–pathogen interactions and virulence. Here, we showed that VdSOD5 encoded a superoxide dismutase with a cofactor copper-binding site and a functional signal peptide that can conduct protein secretion in an invertase-mutated yeast strain. The mutations in VdSOD5 (ΔVdSOD5) did not change the normal vegetative growth and conidial production but reduced the virulence of V. dahliae on susceptible host cotton. Further studies showed that the transcription of VdSOD5 was significantly up-regulated during the early stage of infection, and the loss-of-function of VdSOD5 decreased culture filtrate and fungal tissue SOD activities of V. dahliae by 74 and 28%, respectively. Compared to the wild-type strain Vd991, the ΔVdSOD5 showed the same sensitivity to the intracellular ROS generator menadione. Furthermore, nitroblue tetrazolium (NBT) staining demonstrated that VdSOD5 functioned in the detoxification of superoxides generated by host roots during infection. These results suggest that VdSOD5 of V. dahliae is an important virulence factor, secreted out of cells to combat host-derived ROS.

Baicalin has anti-inflammatory, antibacterial, blood platelet aggregation-inhibiting, free oxygen radical-clearing, and endotoxin-decreasing properties. However, its molecular mechanism involved in the treatment of Adriamycin-induced nephrotic syndrome (NS) is still unclear. This study aimed to explore the effects of baicalin on Adriamycin-induced nephrotic syndrome (NS) and to characterize the genes involved in this progression. We established Adriamycin-induced NS model in 32 rats and used six rats in Sham group. Urinary total protein content and creatinine serum were assessed as physiological indicators. H&E staining was used to observe the pathological changes. We determined gene expression profiles using transcriptome sequencing in the rat kidney tissues from Sham, Adriamycin, and Adriamycin + baicalin groups. KEGG was carried out to analyze the enriched pathways of differentially expressed genes among these groups. Baicalin treatment relieved renal injury in NS rats. Expression of 363 genes was significantly different between the Adriamycin and Adriamycin + baicalin M groups. Most of the differentially expressed genes were enriched in pathways involved in epithelial-mesenchymal transition (EMT), fibrosis, apoptosis, and inflammation. Overall, these data suggest that Adriamycin-induced NS can be attenuated by baicalin through the suppression of fibrosis-related genes and inflammatory reactions. Baicalin is a potential drug candidate for the treatment of NS, and the identified genes represent potential therapeutic targets.

The long-term accumulation of pesticide residues brought a huge threat to healthy lives of animals and humans. However, traditional detection methods for pesticide residues required expensive equipment and tedious operation. An electrochemiluminescence (ECL) aptasensor based on nano-antimony tin oxide and titanium dioxide composites (ATO@TiO2) and silver nanoparticles (AgNPs) for rapid detection of malathion residues had been developed to solve the above problems. The ATO@TiO2 greatly improved luminous intensity and signal output of ECL aptasensor based on luminol-hydrogen peroxide system because it could load large amounts of luminol and had excellent conductivity. As a wonderful catalyst, AgNPs further enhanced the signal output of the whole sensor and solved the problem of weak luminous intensity of luminol. Thanks to the synergistic effect of ATO@TiO2 and AgNPs, the aptasensor obtained an ultra-sensitive detection capability of malathion residues, and the detection limit was reduced to 25 fg/mL (S/N = 3). Under optimal conditions, the linear detection range of aptasensor could reach 100 fg/mL–10 μg/mL. In the experiment of detecting pesticide residues in real vegetables, the detection ability of the ECL aptasensor was comparable with that of HPLC–MS, and its recovery rate could reach 81.94 to 104.29% (RSD

The fluorescent functional material prepared by combining 16‐alkyl (ferrocenyl‐methyl) ammonium bromide (Fc16AB) and dye molecule Congo red (CR) via ionic self‐assembly strategy exhibits double stimuli‐responsive behavior triggered by redox and pH value. Both the fabrication and switching mechanism of aggregates are proposed according to the cooperative binding of noncovalent interactions, including π‐π stacking, electrostatic interactions, charge transfer interaction, and amphiphilic hydrophobic association. The optimal geometry and energy transfer between monomers and aggregate are studied by means of quantum chemistry calculation and wavefunction analysis, which provides a deep and theoretical understanding for formation mechanism of ionic self‐assemblies. Moreover, the fluorescent switching behavior of assemblies upon pH was studied in detail, which opens the new way for the construction of organic light‐emitting diode (OLED).

An efficient and inexpensive double transition metal oxide catalyst, MoO2/β-MnO2 composite is developed for oxygen reduction reaction (ORR) and showing better performance than either MoO2 or β-MnO2. The composite catalyst was made into a multi-layered cathode (MLC) for a direct glucose fuel cell (GFC). The MLC consists of a graphite flake and several porous catalyst layers attached to both sides, allowing more adsorption and reaction sites for O2. The better cathode performance over single metal oxide catalysts or single-layer electrodes is confirmed by cyclic voltammetry (CV) and Tafel analysis. By coupling the MLC with a glucose oxidation system catalyzed by Fe(III)/H3PO4, a double-chambered GFC device has been built with an open-circuit potential of 0.68 V and a stable current density of 24 mA·cm−2. Therefore, the utilization of bimetallic multi-layer porous cathodes is a good method to improve the efficiency of ORR for fuel cells.

Anthocyanins are natural water-soluble pigments belonging to the large class of flavonoid compounds, which are crucial secondary metabolites with multiple activities. Anthocyanins ubiquitously exis...

As a common pollutant in food, nitrite has carcinogenicity after long-term consumption. Rapid detection of nitrite in food is an urgent problem to be solved. In the study, poly dimethyl diallyl ammonium chloride-reduced graphene oxide (PDDA-RGO) was prepared by chemical reduction method, and then three-dimensional copper nanodendrites (Cu NDs) were successfully electrodeposited on the surface of PDDA-RGO modified glassy carbon electrode (GCE). The sensor has been successfully applied to the detection of nitrite. PDDA as a hydrophilic cationic polymer effectively avoided the aggregation of RGO. The RGO in the composite material provided a framework for the growing of Cu NDs, which efficiently promoted electron transfer. Moreover, the Cu NDs exhibited pivotal performance in improving the sensitivity and enlarging the specific surface area. The prepared sensing nanocomposites were characterized by cyclic voltammetry (CV), transmission electron microscopy (TEM), scanning electron microscope (SEM), and energy dispersive spectrometer (EDS). Under the optimal conditions, the limit of detection (LOD) of the fabricated sensor was 0.06 μM (S/N = 3), the highest sensitivity was 0.763 μA·μM−1·cm−2, and with linear range of 1–15,000 μM. The sensor performed well in terms of stability and anti-interference, and it provided a new and feasible method for the detection of nitrite in food.

Developing appropriate photothermal agents to meet complex clinical demands is an urgent challenge for photothermal therapy of tumors. Here, platinum-doped Prussian blue (PtPB) nanozymes with tunable spectral absorption, high photothermal conversion efficiency, and good antioxidative catalytic activity are developed by one-step reduction. By controlling the doping ratio, PtPB nanozymes exhibit tunable localized surface plasmon resonance (LSPR) frequency with significantly enhanced photothermal conversion efficiency and allow multiwavelength photoacoustic/infrared thermal imaging guided photothermal therapy. Experimental band gap and density functional theory calculations further reveal that the decrement of free carrier concentrations and increase in circuit paths of electron transitions co-contribute to the enhanced photothermal conversion efficiency of PtPB with tunable LSPR frequency. Benefiting from antioxidative catalytic activity, PtPB can simultaneously relieve inflammation caused by hyperthermia. Moreover, PtPB nanozymes exhibited good biosafety after intravenous injection. Our findings provide a paradigm for designing safe and efficient photothermal agents to treat complex tumor diseases.

Thyroid cancer appears in endocrine glands and specific to thyroid glands has been reported widely. This work was targeted to identify and quantify thyroglobulin by using antithyroglobulin antibody complexed silane surface on interdigitated electrode (IDE) sensing surface. (3-Aminopropyl)triethoxysilane linker was used to make silane-coupling with antibody and attached on the hydroxylated IDE. This electroanalytical IDE revealed the dose-dependent responses with thyroglobulin concentrations. By getting increments with the thyroglobulin concentrations, the current responses were enhanced concomitantly and the thyroglobulin detection limit was noted as 1 pM on the linear curve [y = 0.1311x + 0.5386; R² = 0.9707] with the sensitivity at lower picomolar range. Moreover, the control experiments with thyroid peroxidase and nonimmune antibody cannot yield any response of current, confirming the specific detection of thyroglobulin. This research set-up is useful to determine and quantify the thyroglobulin and diagnose thyroid cancer.

A highly selective turn-on fluorescent and naked-eye colourimetric dual-channel probe for cyanide anions (CNˉ) has been designed and characterized. In the mixed solution (DMSO / H2O, 9:1, v / v), only CNˉ could cause an increase in the UV absorption intensity and the corresponding fluorescence intensity increased, and other anions had no significant effect on the probe. After treatment with cyanide in the probe solution, the solution showed a noticeable colour change, from light yellow to purple. Moreover, a fluorescence spectrophotometer can be used to observe that the fluorescence intensity of the solution is significantly enhanced. The response of the colourimetric and fluorescent dual-channel probe to CNˉ was attributed to nucleophilic addition, and the mechanism was determined by 1H NMR spectroscopy. In addition, this probe was used to detect CNˉ in actual water samples, including river water, drinking water, and tap water. The spiked CNˉ recovery rate is very high (97.2%-100.06%), and analytical precision is also very high (RSD

A key challenge for the discrete distribution-based Förster resonance energy transfer system (D-FRET) is the reduced intensity and stability of signal probes in complex biological matrices. Here, we present a spatially confined FRET (SC-FRET) probe with a stable structure and strong signal output. It consists of multivalent FRET pairs labeled with FAM or TAMRA. In this assay, p53 DNA was chosen as a model hairpin probe (HP), and two kinds of branched DNA probes (ssDNA-FAM, ssDNA-TAMRA) were involved. Under the action of p53 DNA, the unfolded HP acts as a primer to initiate polymerization extension of KFP polymerase and cleavage of Nb.BbvCI endonuclease, which produces plenty of ssDNA (primer-DNA). The branched DNA is designed to have the same binding core and different sticky ends, the core part of which can self-assemble to form X-shaped branched DNA (X-FAM or X-TAMRA), and the sticky ends of which are complementary to the primer-DNA. Therefore, the primer-DNAs released during the polymerization cleavage process will combine a large number of X-FAM and X-TAMRA in a limited space through complementary base pairing. Fluorescence was transferred from FAM to TAMRA, and a strong FRET response was generated by the locational effects. The proposed SC-FRET system based on the multivalent assembly of branched DNA exhibited a strong FRET response with an LOD of 0.01394 pM. Importantly, it also showed a high-contrast and stable FRET response in HeLa cells. Its superior biological stability is attributed to the large steric hindrance of the compact and rigid frame of the SC-FRET probe, which helps prevent intracellular degradation and provides a powerful tool for biomedical research.

Hydrogel-based flexible electronics, especially stretchable human motion sensors, have been intensely investigated in the past few decades. However, challenges remain in the preparation of anti-freezing hydrogels with balanced properties of high sensitivity, large sensing range and suitable mechanical properties in a broad temperature range. In this study, we fabricate a fully-physically crosslinked poly(hydroxyethyl acrylamide)/silk fibroin-LiCl (PHEAA/SF-LiCl) hydrogel with excellent mechanical properties at both room temperature and subzero temperature. Strain sensitivity and durability at both room temperature (25 °C) and low temperature (−30 °C) have been characterized. Strain sensors which can monitor human movements in different situations, including wireless sensing and low temperature sensing have been fabricated, indicating their huge potential in flexible electronics, remote health control and electronic skins.

Paeonia lactiflora Pall. var. trichocarpa is a variety of Paeonia lactiflora Pall., and is currently the peony herb’s principal cultivar group. Here, we study the differences in aromatic components and flowers of different varieties between two groups of cultivars, providing a reference for applying natural fragrance substances of peonies, breeding fragrant flower types, and developing and using improved varieties. Headspace solid-phase microextraction (HS-SPME), gas chromatography-mass spectrometry (GC-MS), peak area normalization for each component relative to content, component library (NIST14/NIST14S) retrieval, and a literature review were used to analyze the volatile compounds in flowers of eight peony varieties, such as “Gaoganhong”, and ten comospore peony varieties, such as “Jinshanhong”. Results showed that the main volatile compound constituents in flowers of the two groups were terpenes and alcohols. Additionally, the content of eucalyptol, caryophyllene, α-Pinene, citronellol, and 3-Hexen-1-ol, acetate, (Z) was high. Peony cultivars contained linalool, (1R)-2,6,6-trimethylbicyclo[3.1.1]hept-2-ene, and 1,4-dimethoxybenzene, while comospore peony varieties contained 1,3,6-octatriene, 3,7-dimethyl-, (Z)-, phenylethyl alcohol, and geraniol. In this study, the differences between the volatile components of flowers of different peony varieties were clarified, laying a foundation for further molecular biology research into the floral fragrance of peonies and the cultivation of new varieties of aromatic peonies. At the same time, it also provides a theoretical basis for the development and application of peony flower by-products.

Herbaceous peony is an ornamental plant with medicinal properties. Waterlogging can affect its yield and quality as it grows and matures. In this study, we subjected “Taohuafeixue”, “Yangfeichuyu” and “Hongxiuqiu” herbaceous peony varieties to a simulated waterlogging stress treatment and investigated the effects of waterlogging on their physiological characteristics and the secondary metabolite contents in their leaves and roots. Short-term waterlogging caused the leaves to turn yellow or red and the roots to turn black. The stele and the cell wall of the endothelial cells thickened, and the cortical cells enlarged. Waterlogging did not significantly change plant height, leaf length, and leaf area; however, it significantly decreased the root-shoot ratio of “Yangfeichuyu” and “Hongxiuqiu” varieties. The activity of antioxidant enzymes and the content of osmotic regulators increased under waterlogging. After short-term waterlogging stress treatment, the content of paeoniflorin and albiflorin increased in the roots of “Taohuafeixue” and “Yangfeichuyu”, and the content of benzoylpaeoniflorin increased in the root of “Hongxiuqiu”. The content of gallic acid and total flavonoids increased in the leaves of “Taohuafeixue” and “Yangfeichuyu”. After the waterlogging, paeoniflorin and benzoylpaeoniflorin increased in the autumn root of “Hongxiuqiu”. This study expands our knowledge about the medicinal properties of herbaceous peony and informs about its production and cultivation under waterlogged conditions.

Based on tetraphenylethylene as the skeleton, two novel salamo-type fluorescent probes (TPES1 = 2-hydroxy-1-naphthaldehyde O-(3-(((-2-hydroxy-5-(1,2,2-triphenylvinyl)benzylidene)amino)oxy)propyl) oxime and TPES2 = bis(2-hydroxy-1-naphthaldehyde O-(3-(((2-hydroxy-5-(1,2,2-triphenylvinyl)benzylidene)amino)oxy)propyl) dioxime) were designed and synthesized. Through the colorimetric and fluorescence dual-channel modes, cyanide ions could be specifically recognized by the two probe molecules. Interestingly, the probes TPES1 and TPES2 exhibited completely different spectral behaviors during the recognition process. Of the two, the TPES1 molecule is a ratio-type fluorescent probe, and double fluorescence emission peaks appeared during the titration process. The reason for this phenomenon is due to the rotation of the C–C single bond in tetraphenylethylene, causing the solution system to contain molecules in two states. On the other hand, the TPES2 molecule is a fluorescence-enhanced probe that has undergone two reaction processes of deprotonation and addition reaction successively, causing the fluorescence intensity to increase continuously. Theoretical calculations indicated that the configuration of probe TPES1 is reversed after interacting with cyanide ions (CN−). By calculating the minimum detection limits of TPES1 and TPES2 to CN−, the LOD values were 8.56 × 10−8 M and 5.37 × 10−8 M, respectively. In addition, probe-based test strips have been prepared for quick and simple detection of cyanide ions.

Broad-spectrum antibodies can effectively recognize substances with similar structures and have broad application prospects in field rapid detection. In this study, broad-spectrum antibodies (Abs) against organophosphorus pesticides (OPs) were used as sensitive recognition elements, which could effectively recognize most OPs. Gold nanoparticles (AuNPs) have good biocompatibility. It combined with Abs to form a gold-labeled probe (AuNPs–Abs), which enhances the effective binding of antibodies to nanomaterials. Prussian blue (PB) was added to electrodeposition solution to enhance the conductivity, resulting in superior electrochemical performance. The AuNP–Abs–PB composite film was prepared by electrodeposition on the electrode surface to improve the anti-interference ability and stability of the immunosensor. Under the optimal experimental conditions, the immunosensor had a wide detection range (IC20–IC80: 1.82 × 10–3–3.29 × 104 ng/mL) and high sensitivity. Most importantly, it was simple to be prepared and could be used to detect multiple OPs.

In this paper, a dual-signal amplified electrochemical immunosensor for quantitative detection of capsaicinoids in serum was reported, which could be used to study the pharmacological properties of capsaicinoids. To improve the sensitivity of the immunosensor, the glassy carbon electrode was modified with Prussian blue-gold nanocomposites (PB-AuNPs) and thionine (TH). PB-AuNPs provided better electrical conductivity. At the same time, TH enhanced the stability of electron transfer, leading to superior electrochemical performance. Meanwhile, an excellent anti-capsaicinoids antibody (Ab) was used to ensure the sensitivity and specificity of the electrochemical immunosensor. The prepared immunosensor was tested using cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Under the optimal conditions, the proposed immunosensor displayed a wide linear range from 0.01 to 1000 ng/mL with a detection limit of 0.01 ng/mL and showed good recoveries (85.12–104.25%) and high stability. Additionally, the immunosensor was successfully applied to monitor capsaicinoids in real serum samples.

Hydrogel-based strain sensors have been widely investigated owing to their intrinsic flexible and extensible properties. However, integrating good mechanical properties and excellent strain sensitivity into one hydrogel remains a challenge. In this work, a dual physical cross-linked carboxymethyl cellulose-Fe3+/polyacrylamide (CMC-Fe3+/PAAm) double network hydrogel was developed by facile two-step method. In this hydrogel, the Fe3+ cross-linked CMC acts as the first network for dissipating energy and hydrophobic association PAAm acts as the second network to maintain the integrity of hydrogel. Owing to these physical interactions, the as-prepared hydrogel shows good mechanical properties (e.g., tensile strength, 1.82 MPa; toughness, 6.52 MJ/m3). Furthermore, these mechanical behaviors can be modulated by adjusting the solid content, CMC/PAAm ratio, Fe3+ concentration and soaking time in Fe3+ solution. Moreover, the obtained hydrogel shows excellent self-recovery and anti-fatigue property due to the reversibility of dual physical cross-linked interactions. Additionally, the CMC-Fe3+/PAAm hydrogel shows good conductivity (1.82 S/m), strain sensitivity (gauge factor = 4.02 at 50–600% strain), and fast response time (260 ms). Based on the high strain sensitivity, the CMC-Fe3+/PAAm hydrogel can fabricate a flexible strain sensor for precisely monitoring various human motions. This study suggests that the CMC-Fe3+/PAAm hydrogel exhibits potential application in the flexible and stretchable strain sensors.

An electrochemical tetrahedral APT biosensor (Au-TAN biosensor) was successfully constructed, which had a stable structure and excellent performance using tetrahedral DNA nanomaterials (TDN) and Au nanoparticles (AuNPs) for the detection of acetamiprid. Specifically, we designed a partial paired complementary DNA (cDNA) of acetamiprid aptamer and inserted the cDNA together with the acetamiprid aptamer into four single-stranded DNA sequences forming each side of the TDN, modifying AuNPs to increase the current signal intensity, to assemble the Au-TAN. This proposed aptasensor was compared with ssAPT aptasensor and tetrahedral APT nanostructures (TAN) aptasensor, respectively. The results showed that the performance of the designed aptasensor was better than those of the above two aptasensors. The detection limit of the aptasensor was calculated to be 0.077 pM (S/N = 3), which was far lower than that of other methods that we compared. Under optimized conditions, the proposed aptasensor showed a wide linear detection range from 0.1 pM to 10 nM. The Au-TAN biosensor opens up new ideas for the construction of aptasensors and provides a new method for detection of small molecular substances, such as pesticides residues.

Background Quercetin was reported to be crucial for a broad range of activities, including attenuating inflammation, platelet aggregation, capillary permeability, and lipid peroxidation. However, the effect of quercetin in hypertension during pregnancy, was not fully understood. Methods The model of hypertension in pregnancy was established in rats by reduced uterine perfusion pressure (RUPP). Quercetin was administrated by gavage. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured using the CODA 6 BP system. Plasma concentrations of Endothelin-1 (ET-1), soluble fms-like tyrosine kinase-1 (sFlt-1), and vascular endothelial growth factor (VEGF) were detected using enzyme-linked immunosorbent assay kits. The mRNA and protein levels of ET-1 and endothelin-1 type A receptor (ETAR) were determined by RT-PCR and Western blotting. The ETAR antagonist BQ-123 was performed by osmotic minipumps. Results In RUPP induced rats, quercetin treatment decreased SBP and DBP, fetal resorptions percentage, plasma ET-1 and sFlt-1 concentrations, ET-1 and ETAR levels, but increased fetal body weight and VEGF expression. BQ-123 administration attenuated SBP and DBP, suppressed fatal resorptions percentage, and increased fetal body weight of RUPP rats. Conclusion Quercetin attenuates RUPP induced hypertension in pregnant rats through the regulation of ET-1 and ETAR.

Three Ni(II) complexes {[NiL(μ-OAc)(CH3CH2OH)]2Ni} (1), {[NiL(μ-OAc)(CH3OH)]2Ni]·2CH2Cl2·2CH3OH (2) and {[NiL(μ-OAc)(CH3OH)]2Ni}·1.5CH3OH (3) based on a Salamo-type bis-oxime ligand (H2L = 2,2′-[ethylenedioxybis(nitrilo-methylidyne)]dinaphthol) have been synthesized and characterized by physicochemical and spectroscopic methods. The complexes 1, 2 and 3 are all trinuclear structures, and the center Ni(II) ions are six-coordinated and show the slightly distorted octahedral coordination. They all consist of three Ni(II) ions, two deprotonated L2- units, two μ-acetato ligands and two coordinated solvent molecules, as well as the crystallizing solvent molecules. Although the molecular structures of the Ni(II) complexes 1, 2 and 3 are similar to each other, obtained in different solvents, the supramolecular structures are entirely different. The complexes 1, 2 and 3 possess the self-assembled infinite 1D, 3D and 2D supramolecular structures via different intermolecular interactions (hydrogen bonds, C–H···π and π···π stacking interaction), respectively. But complex 2 formed a 3D structures by intramolecular hydrogen bonds. It is significant that the solvent molecules have obvious effects on the optical properties and molecular configuration. The Hirshfeld surface analysis showed that the short-range forces of the hydrogen bonds in complexes 1, 2 and 3 accounted for 67.8%, 44.6% and 52.7%, respectively. The molecular orbital energies for ligand H2L and complex 1 were obtained by DFT calculation, and the electron distribution, energy level and energy gap of HOMO and LUMO were given.

Labeling viruses with high-photoluminescence quantum dots (QDs) for single virus tracking provides a visual tool to aid our understanding of viral infection mechanisms. However, efficiently labeling internal viral components without modifying the viral envelope and capsid remains a challenge, and existing strategies are not applicable to most viruses. Here, we have devised a strategy using the clustered regularly interspaced short palindromic repeats (CRISPR) imaging system to label the nucleic acids of Pseudorabies virus (PRV) with QDs. In this strategy, QDs were conjugated to viral nucleic acids with the help of nuclease-deactivated Cas9/gRNA complexes in the nuclei of living cells and then packaged into PRV during virion assembly. The processes of PRV-QD adsorption, cytoplasmic transport along microtubules, and nuclear entry were monitored in real time in both Vero and HeLa cells, demonstrating the utility and efficiency of the strategy in the study of viral infection.

Nanozymes have been widely used in biomedicine, especially in tumor therapy. However, inadequate H2O2 supply in the tumor microenvironment (TME) and uncontrolled catalytic activity of nanozymes in vivo restrict their practical application. Here, a dark/light relay strategy is proposed to realize adequate H2O2 supply in the dark reaction stage and selectively perform desired catalytic activities for toxic reactive oxygen species (ROS) generation to kill tumors by remote light control. A tumor membrane camouflaged and glucose oxidase (GOx) loaded hollow mesoporous Prussian blue (mGPB) nanosystem is designed to target tumor tissues for homologous aggregation of membranes. The cascaded catalysis of superoxide dismutase (SOD) and catalase (CAT)-like activities inherited from hollow mesoporous Prussian blue (HMPB) efficiently catalyze endogenous O2−˙ to O2, which contributes to the oxidative decomposition of glucose to produce H2O2 by loaded GOx. Moreover, mGPB nanoparticles are found to utilize H2O2 to produce ˙OH and 1O2 under NIR irradiation via other light-dependent dual-catalytic properties, acting as peroxidase (POD) and oxidase (OXD). By dark/light relay catalysis, we successfully overcome the limited H2O2 supply in TME and achieve precise ROS generation, displaying prominent tumor suppression in mouse xenograft models.

Flexible and stretchable electronics have received tremendous attention for next-generation human-friendly electronic applications. However, fabrication of transparent, fully recyclable and stretchable electronic sensors with low-temperature stability using biocompatible natural polymer-based hydrogels still remains a great challenge. In this study, a green and fully recyclable stretchable electronic sensor with high transparency and ultra-low operating temperature is constructed using ionic conductive gelatin organohydrogels. These gelatin organohydrogels are prepared by a simple strategy of immersing gelatin pre-hydrogels in citrate (Na3Cit) water/glycerol solutions. The existence of Na3Cit in the organohydrogel not only induces the formation of multiple non-covalent cross-linking points, endowing the organohydrogel with high mechanical performances, but also makes the organohydrogel have excellent ionic conductivity. The organohydrogel is also highly transparent and exhibits outstanding antifreezing properties. The mechanical robustness, conductivity and transparency of the organohydrogel can be well maintained even at −60 °C. As a result, a stretchable and transparent electronic sensor based on this organohydrogel is fabricated, which is strain-sensitive with a large linear sensing window and excellent stability. More importantly, the organohydrogel-based electronic sensor can be fully recycled due to the reversible non-covalently crosslinked structure, and the recycled organohydrogel regains its mechanical and sensing properties. The obtained sensors could precisely detect various human activities even below −30 °C, indicating the potential applications of the organohydrogel-based electronic sensor in flexible and stretchable electronics in a broad range of temperature.

In this paper, a sensitive electrochemical immunosensor modified with graphene oxide–chitosan (GO–CS) and cerium oxide–chitosan (CeO2–CS) using screen-printed electrodes (SPEs) was developed for the determination of aflatoxin M1 (AFM1) in milk. Compared with other electrodes, SPEs are easy for quick detection and no polishing steps are required. Graphene oxide (GO) has strong electrical conductivity and a large specific surface area, which can accelerate the transfer of electrons and fix more anti-AFM1 antibodies (ab-AFM1) on SPEs. Compared with GO, cerium oxide (CeO2) nanoparticles have a smaller diameter, and CeO2 can be uniformly attached to the surface of the GO. Simultaneously, CeO2 has good redox properties and can further accelerate the transfer of electrons, thereby further amplifying the electrochemical signal of the sensor. Chitosan (CS) has strong complexation ability, which can uniformly disperse GO and CeO2. Herein, GO–CS and CeO2–CS gradually modified SPEs to improve their electrochemical response and immobilize more antibodies. The properties of the AFM1 immunosensor were studied via differential pulse voltammetry (DPV) and cyclic voltammetry (CV). Under the optimal conditions, the immunosensor showed great reproducibility and high stability with a detection limit of 0.009 μg L−1. In addition, the immunosensor was successfully utilized for the determination of AFM1 in milk. This immunosensing principle will have broad prospects for the analysis of toxins in food, ensuring the safety of milk and dairy products.

The photodynamic therapy (PDT) as a promising antitumor therapy technique is greatly hampered by the low tissue penetration of light and the photothermal effect of prolonged irradiation. Near-infrared (NIR) persistent luminescence nanoparticles (NPLNPs) possess the potential for application in next-generation PDT. However, owing to the low re-excitation efficiency of NPLNPs in deep tissue, the current PDT nanoplatform based on NPLNPs is faced with the disadvantage of decreased PDT efficiency induced by persistent luminescence (PersL) decay at the lesion site. Herein, NPLNPs, Zn

Plant pathogens generally employ superoxide dismutase (SOD) to detoxify host defense reactive oxygen species (ROS), and to scavenge ROS derived from their own metabolism. However, the roles of SODs in an important vascular pathogen, Verticillium dahliae, are unclear. Our previous study has shown that a putative signal-peptide-lacking manganese superoxide dismutase (VdSOD3) is present in the exoproteome of V. dahliae cultured in tissues of host cotton, suggesting that VdSOD3 may be exported out of the fungal cells and contribute to the SOD activity extracellularly. Here, we confirm that the N-terminal of VdSOD3 is not a functional signal peptide by yeast signal trap assay. Despite lacking the signal peptide, the extracellular distribution of VdSOD3 was observed in planta by confocal microscopy during infection. Loss-of-function of VdSOD3 decreased extracellular and intracellular SOD activities of V. dahliae by 58.2% and 17.4%, respectively. Deletion mutant of VdSOD3 had normal growth and conidiation but showed significantly reduced virulence to susceptible hosts of cotton and Nicotiana benthamiana. Our data show that signal-peptide-lacking VdSOD3 is a dual function superoxide dismutase, localizing and functioning intracellularly and extracellularly. Whereas nonessential for viability, VdSOD3 plays a vital role in the virulence of V. dahliae.

Microplastics (MPs) are ubiquitous in farmland soils. However, few studies have evaluated their effects on the microbial community structure and nitrogen cycle of farmland soils. Here, 0.3% and 1% (mass percentage) of polyethylene terephthalate (PET), polyvinyl chloride (PVC), and polylactic acid (PLA) MPs were added to paddy soil to evaluate their impact on the paddy soil microenvironment. The alpha index of the PLA MP treatment was significantly different from that of the control group (p-value 0.05). In contrast, the indices of the PET and PVC MP treatments were not different from the control (p-value 0.05). Among the MP treatments, the alpha index of the PLA MP group was significantly different from the PET and PVC MP groups (p-value 0.05). PCoA analysis also indicated that there were differences between PLA and other MP groups, and different MP concentrations and exposure times had a great impact on microbial composition. The three MPs affected NH

Multifunctional N6-methyladenosine (m6A) has been revealed to be an important epigenetic component in various physiological and pathological processes, but its role in female ovarian aging remains unclear. Thus, we demonstrated m6A demethylase FTO downregulation and the ensuing increased m6A in granulosa cells (GCs) of human aged ovaries, while FTO-knockdown GCs showed faster aging-related phenotypes mediated. Using the m6A-RNA-sequence technique (m6A-seq), increased m6A was found in the FOS-mRNA-3′UTR, which is suggested to be an erasing target of FTO that slows the degradation of FOS-mRNA to upregulate FOS expression in GCs, eventually resulting in GC-mediated ovarian aging. FTO acts as a senescence-retarding protein via m6A, and FOS knockdown significantly alleviates the aging of FTO-knockdown GCs. Altogether, the abovementioned results indicate that FTO in GCs retards FOS-dependent ovarian aging, which is a potential diagnostic and therapeutic target against ovarian aging and age-related reproductive diseases.

The occurrence, spatiotemporal variations, influence factors and environmental risks of eight common neonicotinoids (NEOs), fipronil, and three fipronil metabolites (fipronil and its metabolites are collectively referred to as FIPs) in different seasons from the estuary to the inner area of Jiaozhou Bay, China were comprehensively investigated. First- and second-generation NEOs were found to be the predominant pesticides in this area. The average contents of ∑NEOs and ∑FIPs from the estuary to the inner bay decreased from 12.99 ng/L to 0.82 ng/L and from 1.10 ng/L to 0.17 ng/L, respectively. NEO and FIP concentrations were higher in summer and autumn. High ∑NEO content is distributed in main inflow rivers, such as Dagu River and Licun River, which are influenced by pesticide application. NEO concentrations in all rivers were high upstream and low downstream because of the influence of heavy rainfall and seawater dilution in summer. NEO concentrations were high along the coast and low at the mouth and center of Jiaozhou Bay in summer and autumn and evenly distributed in winter and spring. Temperature has a great influence on most NEOs and FIPs owing to its effect on their degradation. Nitrogen-containing nutrients have an important influence on the distribution of fipronil and acetamiprid, which may be due to the activity of nitrogen-containing functional groups in their structure. Only Licun River, Dagu River and Haibo river sewage treatment plant in summer posed a certain risk of chronic toxicity for NEOs using the new threshold established by the species sensitive distribution (SSD) method for Chinese native aquatic lives. These findings should arouse people's attention.

As a new member of the 2D material family, MXene integrates high metallic conductivity and hydrophilic property simultaneously. It shows tremendous potential in fields of energy storage, sensing, electromagnetic shielding, and so forth. Due to the abundant surface functional groups, the physical and chemical properties of MXene can be tuned by the formation of MXene-polymer composites. The introduction of polymers can expand the interlayer spacing, reduce the distance of ion/electron transport, improve the surface hydrophilicity, and thus guide the assembly of MXene-polymer structures. Herein, the preparation strategies of MXene-polymer composites including physical mixing, surface modification, such as anchoring through TiN and Ti-O-C bonds, bonding through esterification, grafting functional groups through TiOSi/TiOP bonds, photograft reaction, as well as in situ polymerization are highlighted. In addition, the possible mechanisms for each strategy are explained. Furthermore, the applications of MXene-polymer composites obtained by different preparation strategies are summarized. Finally, perspectives and challenges are presented for the designs of MXene-polymer composites.