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In this study, a functionalized Co3O4-Bi2O3-Ti catalytic membrane (CBO-Ti-M) was prepared and applied for removing organic pollutants via activating peroxymonosulfate (PMS) in the dead-end filtration mode. Characterizations including scanning electron microcopy (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) showed that the Co3O4-Bi2O3 catalyst was successfully supported on the Ti membrane. The CBO-Ti-M /PMS system could efficiently remove various organic pollutants such as sulfamethoxazole, methyl orange, bisphenol A and methylene blue, achieving removal efficiencies of 98.0%-99.5%. The effects of PMS concentration, flow rate and solution environment on degradation efficiency were investigated in detail. Furthermore, quenching experiments, electron spin resonance (ESR) and in-situ open circuit potential (OCP) tests collectively demonstrated that singlet oxygen as well as the non-radical electron transfer pathway mainly contributed in the reaction mechanism. The synergistic effect of Co and Bi was illustrated according to XPS results, and the possible degradation pathway of MB was proposed based on LC-MS analysis. Reusability test showed that pollutant removal efficiency with the CBO-Ti-M /PMS system remained stable in four runs and limited metal leaching was observed.

Compared with carbon nanotube (CNT) and graphene (GE) aerogels, the synthesis of three-dimensional (3D) carbon nanofiber (CNF) aerogels that are highly compressible, resilient under cyclic strains, and creep and fatigue resistant remains extremely challenging. Herein, a revolutionary green and scalable biosynthesis is presented, by which a novel 3D CNF aerogel derived from natural bacterial cellulose (BC) decorated with its mother bacteria is created. The as-prepared CNF aerogel possesses excellent mechanical resilience, ultra-low energy loss coefficient, and outstanding cycling stability, which are by far among the best performances for CNT and GE aerogels reported thus far. Furthermore, the CNF aerogel exhibits excellent creep and fatigue resistance and sensitive electrical conductivity change upon compression. Surprisingly, the as-prepared 3D CNF aerogel exhibits superhydrophilicity. These superb properties are attributed to the existing carbonized bacteria in the carbonized BC matrix that serve as crosslinks to strengthen the aerogel and buffers to store deformation energy. This study presents a breakthrough method for the construction of superb and cost-effective 3D CNF aerogel from natural biomass material.

The present study demonstrates a series of environmentally friendly lanthanum and titanium doped mesoporous bioactive glass with adsorption, photocatalytic and regeneration performance for methylene blue via the sol-gel method. The materials were studied by XRD, XPS, TEM and BET. The influence of the initial dye concentration, contact time, solution pH, temperature, photocatalytic performance and regeneration performance of this glass adsorbed methylene blue were investigated. It is shown that the Freundlich and Langmuir adsorption isotherms can be used to study the equilibrium of methylene blue removal process by bioactive glass. Another test on photocatalytic degradation performance and reproduction performance of the materials by removing methylene blue. This article has its potential in treatment of dyeing waste water as it improves structure and performance by adding La and Ti to mesoporous bioactive glass.

The efficient conversion of CO2 to chemical fuels driven by solar energy is still a challenging research area in photosynthesis, in which the conversion efficiency greatly relies on photocatalytic ...

In this study, the electrochemical dechlorination of triclosan in aqueous solution on palladium/polypyrrolereduced graphene oxide/foamed nickel composite electrode (Pd/PPy-rGO/foam-Ni electrode) was investigated. The influences of the applied current, reaction temperature and the initial concentration of triclosan solution on triclosan dechlorination efficiency were studied. The triclosan can be completely removed within 180 min under the conditions of the dechlorination current of 7 mA and dechlorination temperature of 40 °C when the initial concentration of triclosan was 50 mg · L–1.

A fluorescent monolayered two‐dimensional polymer (2DP) containing both tetraphenylethylene (TPE) and imine linkages is synthesized at air‐water interface using the Langmuir‐Blodgett method. We designed TPE‐based monomers with long distances between the TPE and the imine linkages to avoid the charge transfer and therefore keep the fluorescence. A monolayered 2DP provided with more than 104 μm2 in domain size and around 0.8 nm thickness was obtained through a successive Schiff base reaction at air‐water interface. The nanostructures and fluorescent property of 2DP films were characterized by optical microscopy, SEM, TEM, AFM and fluorescence spectrum. Most importantly, the tip‐enhanced Raman spectroscopy (TERS) was utilized here to confirm the success of the polycondensation of monolayered 2DP., A large‐area, monolayered fluorescent two‐dimensional polymer containing both TPE and imine linkage was obtained on the air‐water interface (Langmuir‐Blodgett method). The tip‐enhanced Raman spectroscopy (TERS) was utilized here to confirm the success of the polycondensation of monolayered 2DP. The long distance between the TPE and the imine linkages aviod the charge transfer and therefore keep the fluorescence.

In this study, a new composite electrode of palladium (Pd) nanoparticles dispersed on polypyrrole-reduced graphene oxide (PPy-rGO) loaded on foam-nickel was achieved by galvanostatic method. Characterization of structures, morphology and crystallinity of the synthesized materials were investigated by scanning electron microscopes (SEM), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), Raman spectroscopy and electrochemical impedance spectroscopy (EIS). The results of XPS and XRD demonstrated Pd showed primarily as Pd0. From SEM and TEM results, we had seen that Pd nanoparticles were dispersible well on the composite electrode. Raman spectroscopy was used to show the state of graphene oxide and further demonstrated that PPy and rGO had existed of on the foam Ni matrix. The data of EIS also suggested the charge transfer of the new composite electrode decreased compared to Pd/PPy/foam-Ni and PPy/foam-Ni composite electrodes. The effect of the electropolymerization potential on Pd/PPy-rGO/foam-Ni electrode for removing triclosan (TCS) was examined. It was found that the removal efficiency of TCS on the composite electrode could reach 100% at electropolymerization potential of 0.7 V and reaction time of 100 min. Keywords: Pd/PPy-rGO/foam-Ni electrode, Triclosan, Electrocatalytic hydrodechlorination, Potentiostatic electropolymerization, Applied potential

Clubroot disease, caused by Plasmodiophora brassicae, is a serious soil-borne disease of Brassica crops worldwide. Pakchoi is one of the most important cruciferous vegetable crops and commonly infected by P. brassicae. To date, the physiological changes and mechanism of pakchoi in response to P. brassicae are largely unknown. In this study, seedlings of two pakchoi cultivars, cv. Xinxiaqing (a clubroot-susceptible cultivar) and Yanlong (a less susceptible cultivar than Xinxiaqing), were inoculated with P. brassicae. Results showed that infected roots were enlarged and changed into club shape galls. Fresh root weight, relative electrical conductivity, the activity of lactate dehydrogenase (LDH) and alcohol dehydrogenase (ADH) in infected roots were significantly induced. In contrast, a significant reduction of root length, root function, and the activity of succinic dehydrogenase (SDH), catalase (CAT), ascorbate peroxidase (APX), and superoxide dismutase (SOD) were observed in diseased roots. Interestingly, activities of malate dehydrogenase (MDH) and peroxidase (POD) in S1 and S2 plant roots were increased and decreased in S3 plant roots. Additionally, infected Xinxiaqing roots showed more serious disease symptoms than Yanlong, and the antioxidant enzyme activities were lowered in Xinxiaqing roots compared with those in infected Yanlong roots, indicating the importance of these enzymes in plant resistance against clubroot disease.

Terahertz time-domain spectroscopy has been widely applied in performing dielectric analysis for various materials. However, air voids trapped in samples will significantly affect the characterization. In this study, the refractive index of mixture samples consisting of iron trioxide and polytetrafluoroethylene in five different mass ratios were measured with terahertz time-domain spectroscopy. In order to extract the intrinsic refractive index of iron trioxide, the effective medium model of CRI was then applied to remove refractive index of PTFE in the sample. The extracted refractive indices were presented as a variable parameter decrease with the increase of iron trioxide content, which also corresponds to the increase of air voids in the tablets. The correlation between trapped air voids and analyte composition roots from the coarse rust particles used in pellets compression. This study shows that the influence of air porosity should be considered when terahertz waves are utilized to characterize dielectric property of coarse material.

For crystalline material with strong terahertz (THz) absorbance, the characterization with terahertz time-domain spectroscopy (THz-TDS) is typically performed on the mixture pellet where the analyte of interest is embedded within an inert polymer matrix. The polymer background significantly affects the phase delay of the propagating THz signal inside the sample, which makes the polymer matrix contribute to the overall dielectric response of the mixture sample to the probing THz waves. In this study, an analytical model was proposed to extract the target analyte’s intrinsic dielectric constants from the experimental dielectric spectra of the diluted mixture.

Circular RNAs (circRNAs), is a novel type of endogenous non-coding RNAs (ncRNAs) participated in the pathogenesis of many diseases. Beryllium is one of the carcinogenesis elements. However, the mechanism and function of circRNAs in human bronchial epithelial cells (16HBE) induced by beryllium sulfate (BeSO4) was rarely reported. Therefore, the high-throughput RNA sequencing analysis was performed to detect the circRNA profiles between control groups and BeSO4-induced groups. Furthermore, circRNA-miRNA-mRNA network, Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, and PPI network analysis were used for bioinformatics analysis. CircRNA sequencing analysis revealed that 36 circRNAs were up-regulated and 35 circRNAs were down-regulated in the BeSO4-exposed groups. The selected circRNAs were verified by real-time fluorescent quantitative PCR (qRT-PCR). Hsa_circ_0004214 and hsa_circ_0003586 were validated to be up-regulated, hsa_circ_0047958, hsa_circ_0001944, and hsa_circ_0008982 were down-regulated. The circRNA-miRNA-mRNA network annotated the key signaling pathway including cellular senescence, TNF signaling pathway, NF-kappa B signaling pathway, HIF-1 signaling pathway, and Hippo signaling pathway. The PPI network indicated the most circRNAs might participate in the BeSO4 toxicity by acting as a sponge for the miR-663b through JAK–STAT signaling pathway. In summary, our study suggests that circRNAs may play roles in the mechanism of beryllium toxicity.

Parkinson's disease (PD) is one of the most common neurodegenerative diseases, which is characterized by the loss of dopaminergic neurons in the nigrostriatal pathway. Synaptic dysfunction impairs dopamine turnover and contributes to the degeneration of dopaminergic neurons. However, the molecular mechanisms underlying synaptic dysfunction and dopaminergic neuronal vulnerability in PD are not clear. Here, we report that synaptojanin 1 (SYNJ1), a polyphosphoinositide phosphatase concentrated at nerve terminals, is a substrate of a cysteine proteinase, asparagine endopeptidase (AEP). SYNJ1 is cleaved by the cysteine proteinase AEP at N599 in the brains of PD patients. AEP-mediated cleavage of SYNJ1 disrupts neuronal phosphoinositide homeostasis and causes synaptic dysfunction. Overexpression of the AEP-generated fragments of SYNJ1 triggers synaptic dysfunction and the degeneration of dopaminergic neurons, inducing motor defects in the α-synuclein transgenic mice. Blockage of AEP-mediated cleavage of SYJN1 alleviates the pathological and behavioral defects in a mouse model of PD. Our results demonstrate that the fragmentation of SYNJ1 by AEP mediates synaptic dysfunction and dopaminergic neuronal degeneration in PD.

A sulfur-rich graphdiyne (TTF-GDY) material containing electrochemically active unit of tetrathiafulvalene was successfully synthesized at the liquid/liquid interface under mild conditions. The extended two-dimensional (2D) π-conjugated framework contains large in-plane cavities to accommodate defined sulfur elements and precise sulfur content. Transmission electron microscopy (TEM), scanning electron microscopy (SEM), and atomic force microscopy (AFM) characterizations demonstrated that the TTF-GDY adopted the layered structures. X-ray photoelectron spectroscopy (XPS), Raman spectrum, selected area electron diffraction (SAED), crystal modeling, and molecular-mechanics-based calculation further confirmed the proposed framework structure and the expected chemical compositions. Considering the unique structure and sulfur-rich characteristic, we then applied this material as an electrode in lithium battery applications. Due to the unique 2D framework structure, the TTF-GDY exhibited a high specific capacity of 837.6 mAh/g, particularly having a robust long-term stability under the high current density. These results demonstrated that such a sulfur-rich TTF-GDY, as a novel electrochemical material would have great application potential in energy fields.

Novel composite magnetic microspheres containing chitosan and quaternary ammonium chitosan derivative (CHMMs) were prepared by inverse suspension method, and used for the methyl orange (MO) removal from aqueous solutions. The CHMMs were characterized by a scanning electron microscope, a transmission electron microscope, and Fourier transform infrared spectroscopy, respectively. Compared with the chitosan beads, the incorporation of quaternary ammonium chitosan derivative significantly reduced the particle size. The MO adsorption by CHMMs was investigated by batch adsorption experiments. The adsorption kinetics was conformed to the pseudo second-order kinetics equation. The adsorption isotherm followed the Langmuir model better than the Freundlich model and the calculated maximum MO adsorption capacity was 266.6 mg·g−1 at 293 K. Thermodynamic studies indicated that the MO adsorption was endothermic in nature with the enthalpy change (∆ H°) of 99.44 kJ·mol−1. The CHMMs had a stable performance for MO adsorption in the pH range of 4–10, but high ionic strength deteriorated the MO removal due to the shielding of the ion exchange interaction. A 1 mol·L−1 NaCl solution could be used to regenerate the exhausted CHMMs. The proposed CHMMs can be used as an effective adsorbent for dye removal or recovery from the dye wastewater.

The industrial processing of shrimp produces massive quantities of solid waste that is a notable source of animal protein, chitin, carotenoids, and other bioactive compounds that are not appropriately utilized. In the present study, chitin and protein extraction from shrimp head with autolysis and fermentation using Bacillus licheniformis were investigated. The results showed that when shrimp heads were autolyzed with a natural pH at 50°C for 4 h, the total amino acid nitrogen in the supernatant was 5.01 mg mL−1. Then, when a 50% (v/m) inoculum of the hydrolysate was incubated at 60°C for 10 h, a deproteinization rate of 88.3% could be obtained. The fermented supernatant was processed into a dry protein powder, while the residues were demineralized by 10% citric acid for chitin. The recovered protein powder contained 5.5% moisture, 11.5% ash, and 66.7% protein, while the chitin contained 3.5% moisture, 2.1% ash, and 3.1% protein. In addition, amino acids, minerals, heavy metals, the degree of acetylation, microstructure, and Fourier-transform infrared (FT-IR) spectroscopy results were analyzed. Furthermore, the statistics of the large scale trial after treatment with 20 kg of shrimp heads were analyzed. Thus, this work made the shrimp waste utilization environmentally sound and valuable.

In the present work, palladium/polyaniline/foamed nickel (Pd/PANI/Ni) composite electrode was successfully constructed via two-step galvanostatic electropolymerization method. Subsequently, physicochemical properties such as apparent morphologies, crystalline structure, surface state and electrochemical property were characterized through scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD), X-ray photoelectron microscopy (XPS), Fourier transform infrared spectroscopy (FTIR) and Electrochemical impedance spectroscopy (EIS). The effects of the polymerization current, temperature and reaction time of galvanostatic electropolymerization on the composite electrode for the electrochemical dechlorination of 2,4-dichlorophenol (2,4-DCP) were examined. All results indicated that PANI in the Pd/PANI/Ni composite electrode existed in the form of needle-shaped, while nulvalent Pd particles dispersed well as clusters in the network on PANI. Under optimal conditions, in which PANI polymerized on electrode structure with the polymerization current of 24 mA, temperature of 0 °C and time of 20 min, respectively, a 89.1% removal rate of 2,4-DCP could be achieved. Finally, electrochemical dechlorination pathway was investigated and the main dechlorination product was phenol. The composite electrode possessed good stability and excellent electrocatalytic dichlorination performance.

The etiology and pathogenesis of Alzheimer's disease (AD) are not fully understood. Thus, there are no drugs available that can provide a cure for it. We and others found that DNA polymerase-β (DNA pol-β) is required for neuronal death in several neurodegenerative models. In the present study, we tested the effect of a DNA pol-β inhibitor 2',3'- Dideoxycytidine (DDC) in AD models both in vitro and in vivo. DDC protected primary neurons from amyloid-β (Aβ)-induced toxicity by inhibiting aberrant DNA replication mediated by DNA pol- β. Chronic oral administration of DDC alleviated Aβ deposition and memory deficits in the Tg2576 mouse model of AD. Moreover, DDC reversed synaptic loss in Tg2576 mice. These results suggest that DDC represents a novel therapeutic agent for the treatment of AD.

An eco-friendly fluorescent molecularly imprinted polymer anchored on the surface of graphene quantum dots (GQDs@MIP) was developed with an efficient sol–gel polymerization for highly sensitive and selective determination of p-nitroaniline (p-NA). The GQDs@MIP was characterized in detail by Fourier-transform infrared, fluorescence spectrometer, scanning electron microscope, transmission electron microscope and ultraviolet spectrophotometer. The results showed that the imprinted layer was successfully grafted on the surface of the GQDs. The fluorescence of the GQDs@MIP is efficiently quenched when p-NA recombines with the imprinting sites based on the photo-induced electron transfer fluorescence quenching mechanism. A good linear relationship was obtained between the fluorescence quenching efficiency of the GQDs@MIP and the concentration of p-NA in the range of 0–15.0 μM with a correlation coefficient of 0.99. The practicability of the proposed method in real samples was successfully evaluated through monitoring p-NA in water and fish samples with satisfactory recovery. The developed method provides a feasible and eco-friendly strategy to fabricate MIPs anchored on GQDs with good fluorescence properties for sensitive detection of organic pollutants in complex samples.

Fructosyltransferases have been used in the industrial production of fructooligosaccharides (FOS). However, it is still not possible to explain the difference in FOS production based on the variations observed in the FOS synthesizing enzymes of A. niger. In the present study, a novel fructosyltransferase (FT-A) from A. niger TCCC41686 with high FOS synthesis ability was characterized. The FT-A gene was obtained and expressed in Pichia pastoris. A homology model of FT-A showed that the changes of residues identified outside the conserved domains were found to have an effect on its characteristics and its FOS-synthesis capacity. The optimal activity of the recombinant FT-A was observed at 50 °C and pH 6.0, and it was stable below 50 °C and over the range of pH 3.0–11.0. The Km and Vmax values of FT-A were 151.13 g L−1 and 6.55 g L−1 min−1, respectively. The production of FOS using the recombinant FT-A remained above 60% during 50–80 min of synthesis based on sucrose as substrate. The novel fructosyltransferase (FT-A) investigated in this study can potentially be applied for the efficient industrial production of FOS. The results also provide more valuable information for explaining the relationship between the structure and function of the FT-A.

A water-soluble two-dimensional supramolecular organic framework (2D SOF) was prepared via self-assembly of cucurbit[8]uril (CB[8]) and a three-arm flat linker molecule, which contains a benzene ring as the core and three Brooker's merocyanine (BM) analogs as arms. The strong host–guest interactions between BM and CB[8] and the directional head-to-tail stacking modes between the BM arms synergistically led to the formation of a 2D SOF. The structure of the 2D SOF was verified by 1H NMR, 2D 1H NMR NOESY, and DLS characterizations, while the monolayer structure was characterized by Cryo-TEM and AFM measurements. The 2D SOF exhibited an obvious AIE enhancement effect in H2O. In addition, DNA induced photoluminescence enhancement was observed for the monomer. As a result, this AIEgen-based 2D SOF could feature not only as a cell visualizer but also as a tracker for the nucleus in biological imaging due to the dynamic assembly process.

Sprague Dawley rats were exposed to beryllium sulfate (BeSO4), and proteomic and bioinformatic techniques were applied to screen for differentially expressed proteins in their lung tissue and serum. A total of 12 coexpression modules were constructed for 18 samples with 2333 proteins. Four modules were found to have significant differences in the regulation of protein coexpression modules in the serum following exposure to BeSO4. A further three modules had significant differences in the regulation of protein coexpression modules in the lung tissues. Five modules with good correlation were obtained by calculating the gene significance and module membership values, whereas these module Hub proteins included: Hspbp1, Rps15a, Srsf2, Hadhb, Elmo3, Armt1, Rpl18, Afap1L1, Eif3d, Eif3c, and Rps3. The five proteins correlating highest with the Hub proteins in the lung tissue and serum samples were obtained using string analysis. KEGG and GO enrichment analyses showed that these proteins are mainly involved in ribosome formation, apoptosis, cell cycle regulation, and tumor necrosis factor regulation. By analyzing the biological functions of these proteins, proteins that can be used as biomarkers, such as Akt1, Prpf19, Cct2, and Rpl18, are finally obtained.

A novel near infrared fluorescence imprinted sensor based on polyethyleneimine passivated copper-doped CdS quantum dots and zinc oxide nanorods for rapid recognition of ketoprofen was successfully prepared by sol–gel imprinting technology. The results showed that the copper-doped CdS quantum dots passivated with polyethyleneimine could improve the fluorescence lifetime and stability. Zinc oxide nanorods as carriers could improve the fluorescence response speed and sensitivity of the imprinted sensor toward ketoprofen. And the fluorescence imprinted sensor could rapidly recognize ketoprofen in just 1.0 minute. Under optimum conditions, the fluorescence intensity of the fluorescence imprinted sensor was quenched linearly by ketoprofen in the concentration range of 0.05–35.5 μM with a detection limit of 1.36 nM. The fluorescence response mechanism of the fluorescence imprinted sensor toward ketoprofen was discussed in detail, and the fluorescence quenching of the fluorescence imprinted sensor by ketoprofen was attributed to the electron transfer. The fluorescence imprinted sensor was applied to recognize ketoprofen in tap water, lake water, waste water and human urine samples rapidly with the recoveries of 97.3–103.7%. The near infrared fluorescence imprinted sensor provided a new reliable method for rapid and sensitive recognition of drugs in complex samples selectively.

Growing evidence indicates that the dysregulation of mitochondrial calcium (Ca2+) plays a critical role in the growth of tumor cells, including colorectal cancer (CRC). However, the underling mechanism is not fully elucidated. In this study, the regulatory effects of mitochondrial Ca2+ on phosphodiesterase 2 (PDE2)/cAMP/PKA axis and the phosphorylation of mitochondrial transcription factor A (TFAM) as well as the growth of CRC cells were systematically investigated both in vitro and in vivo. Our findings demonstrated that MCU-induced mitochondrial Ca2+ uptake activated mitochondrial PDE2 in CRC cells. Moreover, overexpression MCU in CRC led to a 1.9-fold increase in Ca2+ uptake compared to control cells. However, knockdown of MCU resulted in 1.5-fould decrease in Ca2+ uptake in mitochondria compared to the controls. Activation of mitochondrial PDE2 significantly inhibited the activity of mitochondrial protein kinase A (PKA), which subsequently leads to decreased phosphorylation of TFAM. Our data further revealed that PKA regulates the phosphorylation of TFAM and promotes the degradation of phosphorylated TFAM. Thus, TFAM protein levels accumulated in mitochondria when the activity of PKA was inhibited. Overall, this study showed that the overexpression of MCU enhanced CRC growth through promoting the accumulation of TFAM proteins in mitochondria. Conversely, knockdown of MCU in CRC cells resulted in decreased CRC growth. Collectively, these data suggest that the mitochondrial Ca2+-activated PDE2/cAMP/PKA axis plays a key role in regulating TFAM stability and the growth of CRC cells.

Lagoons along the Red Sea are socio-economically important but most vulnerable ecosystems. Strong evaporation, strengthened due to global warming, leads to high salinity and high temperature in surface water, which exacerbate physiological stress in mangroves. Rabigh Lagoon is characterized by unusually large spatial differences in nutrient dynamics and physicochemical parameters. We conducted a multi-approach study to demonstrate how environmental factors cause growth retardation and stress in mangroves. There were significant variations (P < 0.05) in water salinities and temperatures, nitrogen and phosphorus abundance in sediments, and antioxidants in mangroves among 8 sites across the lagoon. Salinity and water temperature rapidly increased from the northern where Red Sea seawater enters to the southern end, but dissolved oxygen declined. High salinity (44.9), high surface water temperature (28.8°C) and relatively high nutrients at the southern end of the lagoon (S8) corresponded to high concentrations of antioxidants. High δ13C (−12.4‰) and δ15N (4.9‰) in the sediments at S8 also reveal relatively high nutrient level due to stagnant water, camel grazing, and runoff bringing in fertilizer from agriculture activities in the catchments during seasonal flooding events. Principal component analyses showed that N and P limitation at the lagoon entrance is the leading cause for mangrove stress, while high salinity, temperature, and low dissolved oxygen are the predominant factors for high antioxidants concentrations at the southern end of the lagoon.

Beryllium and its compounds are systemic toxicants that are widely applied in many industries. Hydrogen sulfide has been found to protect cells. The present study aimed to determine the protective mechanisms involved in hydrogen sulfide treatment of 16HBE cells following beryllium sulfate-induced injury. 16HBE cells were treated with beryllium sulfate doses ranging between 0 and 300 μM BeSO4 . Additionally, 16HBE cells were subjected to pretreatment with either a 300 μM dose of sodium hydrosulfide (a hydrogen sulfide donor) or 10 mM DL-propargylglycine (a cystathionine-γ-lyase inhibitor) for 6 hr before then being treated with 150 μM beryllium sulfate for 48 hr. This study illustrates that beryllium sulfate induces a reduction in cell viability, increases lactate dehydrogenase (LDH) release, and increases cellular apoptosis and autophagy in 16HBE cells. Interestingly, pretreating 16HBE cells with sodium hydrosulfide significantly reduced the beryllium sulfate-induced apoptosis and autophagy. Moreover, it increased the mitochondrial membrane potential and alleviated the G2/M-phase cell cycle arrest. However, pretreatment with 10 mM DL-propargylglycine promoted the opposite effects. PI3K/Akt/mTOR and Nrf2/ARE signaling pathways are also activated following pretreatment with sodium hydrosulfide. These results indicate the protection provided by hydrogen sulfide in 16HBE cells against beryllium sulfate-induced injury is associated with the inhibition of apoptosis and autophagy through the activation of the PI3K/Akt/mTOR and Nrf2/ARE signaling pathways. Therefore, hydrogen sulfide has the potential to be a promising candidate in the treatment against beryllium disease.

Neurofibrillary tangles composed of hyperphosphorylated tau and synaptic dysfunction are characteristics of Alzheimer’s disease (AD). However, the underlying molecular mechanisms remain poorly understood. Here, we identified Amphiphysin I mediates both tau phosphorylation and synaptic dysfunction in AD. Amphiphysin I is cleaved by a cysteine proteinase asparagine endopeptidase (AEP) at N278 in the brains of AD patients. The amount of AEP-generated N-terminal fragment of Amphiphysin I (1-278) is increased with aging. Amphiphysin I (1-278) inhibits clathrin-mediated endocytosis and induces synaptic dysfunction. Furthermore, Amphiphysin I (1-278) binds p35 and promotes its transition to p25, thus activates CDK5 and enhances tau hyperphosphorylation. Overexpression of Amphiphysin I (1-278) in the hippocampus of Tau P301S mice induces synaptic dysfunction, tau hyperphosphorylation, and cognitive deficits. However, overexpression of the N278A mutant Amphiphysin I, which resists the AEP-mediated cleavage, alleviates the pathological and behavioral defects. These findings suggest a mechanism of tau hyperphosphorylation and synaptic dysfunction in AD.

Brain-derived neurotrophic factor (BDNF) and its tropomyosin-related kinase B receptor (TrkB) are expressed in human osteoblasts and mediate fracture healing. BDNF/TrkB signaling activates Akt that phosphorylates and inhibits asparagine endopeptidase (AEP), which regulates the differentiation fate of human bone marrow stromal cells (hBMSC) and is altered in postmenopausal osteoporosis. Here we show that R13, a small molecular TrkB receptor agonist prodrug, inhibits AEP and promotes bone formation. Though both Receptor activator of nuclear factor kappa-Β ligand (RANKL) and Osteoprotegerin (OPG) induced by ovariectomy (OVX) remain comparable between WT and BDNF +/- mice, R13 treatment significantly elevates OPG in both mice without altering RANKL, blocking trabecular bone loss. Moreover, OVX increases RANKL and OPG in WT and AEP KO mice with RANKL/OPG ratio lower in the latter than the former, attenuating bone turnover. 7,8-DHF, released from the prodrug R13, activates TrkB and its downstream effector CREB, which is critical for OPG augmentation. Consequently, 7,8-DHF represses C/EBPß/AEP pathway, inhibiting RANKL-induced RAW264.7 osteoclastogenesis. Therefore, our findings support that R13 exerts its therapeutic efficacy toward osteoporosis via inhibiting AEP and escalating OPG.

Membrane fouling is an inevitable problem in forward osmosis (FO) treatment of algal-rich water (ARW). Natural ARW has a complex composition. Therefore, the coexisting components (Ca2+, natural organic humic acid [HA], and inorganic particulate kaolinite) in the influence of ARW on FO membrane fouling were studied. The analysis of extended Derjaguin-Landau-Verwey-Overbeek theory and the confocal laser scanning microscopy revealed that the addition of coexisting components increased the attraction between pollutants and membranes, as well as among pollutants to varying degrees, and promoted the development of membrane fouling. Furthermore, Ca2+ and HA aggravated irreversible membrane fouling. All coexisting components changed the distribution and thickness of the fouling layer, and the addition of Ca2+ increased the content of extracellular organic matter (proteins and polysaccharides). The present results enhance the understanding of the mechanism through which natural ingredients affect microalgal membrane fouling and provide a basis for membrane fouling control to treat ARW.

Increasing evidence suggests that oxidative damage and neuroinflammation play a critical role in the pathogenesis of post-stroke depression (PSD). These pathologic processes are tightly regulated by the NF-E2-related factor 2/antioxidant response element (Nrf2/ARE) signaling pathway. The synthetic triterpenoid, 2-Cyano-3,12-dioxooleana-1,9-dien-28-imidazolide (CDDO-Im), is a potent Nrf2 activator. This study investigated whether CDDO-Im exhibited antidepressant-like activity and elucidated its protective mechanisms in a rat model of PSD, which was produced by middle cerebral artery occlusion (MCAO) followed by 28 days of chronic unpredictable mild stress (CUMS) in conjunction with solitary housing. The results demonstrated that CDDO-Im treatment markedly improved the depressive-like behaviors and reduced neuronal cell loss in the hippocampus, through decreasing the malondialdehyde (MDA) content (indicative of lipid peroxidation), superoxide dismutase (SOD), NF-kB activation, interleukin-6 (IL-6) and interleukin-1b (IL-1β) in PSD rats. CDDO-Im treatment alleviated the oxidative stress and inflammatory response in PSD rats by promoting Nrf2 nuclear import and increasing the protein levels of Nrf2 downstream target genes, including heme oxygenase-1(HOMX1) and, quinone oxidoreductase-1(NQO1).These findings suggested that CDDO-Im treatment exhibited antidepressant-like effects and protected PSD rats from oxidative and inflammatory injury via the Nrf2/ARE pathway. Therefore, CDDO-Im treatment is worthy of further study.

Clubroot is one of the most serious diseases affecting Brassicaceae plants worldwide. However, there is no effective control method for clubroot. Salicylic acid (SA) is a plant hormone that plays a critical role in plant defense. In our study, we found the disease severity of a clubroot-sensitive cultivar of pakchoi, Xinxiaqing, was reduced with 0.6mM exogenous SA after the infection of P. brassicae. To investigate the mechanism of SA-reduced disease severity against clubroot, then we analyzed the plant growth, alteration of antioxidant enzyme system, and related gene expression of Xinxiaqing. Results showed that the clubroot incidence rate and disease index were decreased after being treated with 0.6 mM exogenous SA. Furthermore, plant growth, reactive oxygen species (ROS) contents, and membrane lipid peroxidation were changed. The activities of antioxidant enzymes, including superoxide dismutase (SOD), ascorbic acid-peroxidase (APX), catalase (CAT), and glutathione reductase (GR), were increased. Additionally, the production rates of malondialdehyde (MDA), hydrogen peroxide (H2O2), and superoxide anion (O2·–) were also inhibited. The expression levels of genes, encoding SOD, APX, CAT, and GR, were increased. By summering all results, we conclude that 0.6 mM SA contributes to the reduction of disease severity to clubroot by increasing the activities of antioxidant enzymes, abilities of osmotic regulation, and ROS scavenging to reduce the clubroot-induced damage in pakchoi.

Transphosphatidylation catalyzed by phospholipase D has gained increasing attention for producing phosphatidylserine (PS), which can be used in functional food and medicine. In this study, we investigated the effects of six signal peptides on the secretion of PLD (PLDsa) from Streptomyces antibioticus TCCC 21059 in the food-grade GRAS bacterium Bacillus subtilis. It indicated that the optimal signal peptide DacB with an Ala-X-Ala sequence motif at the C-terminus showed the highest secretory expression ability, resulting in increased production of 2.84 U/mL PLDsa. Then PLDsa was immobilized on the epoxy-based carriers, and one of these carriers allowed PLDsa loading of up to 2.7 mg/g. The immobilized PLDsa was more stable over a wide range of pH value (4.5–7.5) and temperature (16 °C–60 °C) than free PLDsa. Subsequently, the synthesis of PS from soybean phosphatidylcholine (PC) was carried out in purely aqueous solution using immobilized PLDsa, leading to a high yield of 65%. The immobilized PLDsa catalyst maintained a relative PS production of 60% after 5 recycles. Notably, the use of toxic solvent was completely eliminated in the whole process, which would be more profitable for the application of PS.

This current study explored the effects of fine particulate matter (PM2.5) on deoxyribonucleic acid methylation in human bronchial epithelial cells. Human bronchial epithelial cells were exposed to PM2.5 for 24 h after which, deoxyribonucleic acid samples were extracted, and the differences between methylation sites were detected using methylation chips. Subsequent gene ontology functional enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed for the differential methylation sites. Functional epigenetic modules analysis of the overall differential methylation site interactions was also conducted. A total of 127 differential methylation sites in 89 genes were screened in the PM2.5 10 μg/ml group, of which 55 sites demonstrated increased methylation, with methylation levels decreasing in a further 72 sites. Following an exposure of 50 μg/ml PM2.5, a total of 238 differentially methylated sites were screened in 168 genes, of which methylation levels increased in 127 sites, and decreased in 111. KEGG analysis showed that the top 10 enrichment pathways predominantly involve hepatocellular carcinoma pathways and endometrial cancer pathways, whereas functional epigenetic modules analysis screened eight genes (A2M, IL23A, TPIP6, IL27, MYD88, ILE2B, NLRC4, TNF) with the most interactions. Our results indicate that exposure to PM2.5 for 24 h in human bronchial epithelial cells induces marked changes in deoxyribonucleic acid methylation of multiple genes involved in apoptosis and carcinogenesis pathways, these findings can provide a new direction for further study of PM2.5 carcinogenic biomarkers.

Given the excellent characteristics of alginate, it is an industrially important polysaccharide. Mannuronan C5-epimerase (MC5E) is an alginate-modifying enzyme that catalyzes the conversion of β-D-mannuronate (M) to its C5 epimer α-L-guluronate (G) in alginate. Both the biological activities and physical properties of alginate are determined by M/G ratios and distribution patterns. Therefore, MC5E is regarded as a biotechnological tool for modifying and processing alginate. Various MC5Es derived from brown algae, Pseudomonas and Azotobacter have been isolated and characterized. With the rapid development of structural biology, the crystal structures and catalytic mechanisms of several MC5Es have been elucidated. It is necessary to comprehensively understand the research status of this alginate-modifying enzyme. In this review, the properties and potential applications of MC5Es isolated from different kinds of organisms are summarized and reviewed. Moreover, future research directions of MC5Es as well as strategies to enhance their properties are elucidated, highlighted, and prospected.

Given the condition that protein conformation and activity are highly susceptible to environment factors such as temperature and pH, evaluation of protein conformation and activity is urgently needed in many fields. For example, most protein drugs need a stable and proper environment during production, storage and transportation, and it’s an enormous challenge to maintain protein activity throughout the whole process. Therefore, it’s necessary to ensure the safety and effectiveness of protein drugs by monitoring their activity before use. In our study, we presented an improved method for non-destructive evaluation of protein conformation and biological activity by terahertz spectroscopy combined with t-SNE-XGBoost. Firstly, bovine serum albumin (BSA) samples heated to different temperature were measured with THz-TDS. The obtained results indicated that native-conformation BSA will undergo transient states in the process of temperature induced denaturation. However, for any single given sample, it’s difficult to identify its conformation and activity directly by using the measured raw terahertz data. Therefore, we applied several different algorithms to the raw data for recognition of BSA samples with different conformation and activity induced by temperature. Finally, the models obtained by different algorithms were evaluated by calculating the root mean standard error of prediction (RMSEP) and the correlation coefficient of prediction ($$R_p$$). The THz-TDS plus t-SNE-XGBoost proved to be an effective non-destructive and label-free method for evaluation of protein conformation and activity. It can provide a new technique in many applications, such as pharmaceutical industry, clinical diagnosis and quality control.

Lysophosphatidic acid is a small extracellular signaling molecule, which is elevated in pathological conditions such as ischemic stroke and traumatic brain injury (TBI). LPA regulates the survival of neurons in various diseases. However, the molecular mechanisms underlying LPA-induced neuronal death remain unclear. Here we report that LPA activates LPA1 and LPA2 receptors, and the downstream MAPK pathway to induce the apoptosis of PC12 cells through mitochondrial dysfunction. LPA elicits the activation of ERK1/2, p38, and JNK pathways, decreases the expression of Bcl2, promotes the translocation of Bax, and enhances the activation of caspase-3, resulting in mitochondrial dysfunction and cell apoptosis. This process can be blocked by LPA1 receptor antagonist and LPA2 receptor antagonist and MAPK pathway inhibitors. Our results indicate that LPA1 receptor, LPA2 receptor and MAPK pathway play a critical role in LPA-induced neuronal injury. LPA receptors and MAPK pathways may be novel therapeutic targets for ischemic stroke and TBI, where excessive LPA signaling exist.

A dual-response ratiometric fluorescence imprinted sensor based on visible/near-infrared emission was established for ultrasensitive, selective and visual detection 4-nitrophenol (4-NP). The molecularly imprinted polymer was incorporated in the ratiometric sensing system consisting of visible emission carbon dots@zeolitic imidazolate framework-8 (CDs@ZIF-8) and near-infrared emission cadmium telluride (CdTe) quantum dots. The CDs@ZIF-8 enhanced the emission of CDs and the fluorescence sensing performance. Compared to short wavelength of fluorophore, the near-infrared emission CdTe is less interference caused by auto-fluorescence of sample. The ratiometric fluorescence imprinted sensor exhibited dual response for 4-NP at 420 nm and 703 nm and a wide concentration response range. Moreover, a good linear response was existed in the two concentration ranges of 0.1 pM–3.0 pM and 0.05 μM–30 μM with the detection limit of 0.08 pM and 0.05 μΜ, respectively. Significantly, the fluorescence color changes can be observed from purple to pink to red with the naked eye. The fluorescence quenching mechanism of the ratimetric fluorescence imprinted sensor was discussed in detail. The ratiometric fluorescence imprinted sensor was used to detect 4-NP in various real samples with satisfactory recoveries of 97.5–106.3%, which provided an interesting avenue for the rapid detection of pollutant with high sensitivity, high selectivity and visualization in real environment.

In this study, the performance of AgNPs-priming (20, 40, and 80 mg/L) on the seed germination, yield, and nutritional quality of Chinese cabbage were evaluated. We found that AgNPs-priming at 20 and 40 mg/L for 15 h significantly accelerated seed germination speed and seedling development. Cabbage seeds primed with different concentrations of AgNPs (0, 20, 40, and 80 mg/L) were then planted in a real soil and allowed to grow for 1 month in greenhouse. Results showed that AgNPs-priming at 40 mg/L significantly increased cabbage yield by 44.3%. Gas chromatography-mass spectrometry (GC–MS) combining with sparse partial least squares-discriminant analysis (sPLS-DA) reveals that AgNPs priming altered the metabolite profile of cabbage leaves in a dose-dependent manner, decreasing carbohydrates and increasing nitrogen related compounds. This indicates that the metabolic stimulation during germination stage can influence the entire life cycle of cabbage. The nutritional quality of cabbage edible leaves was evaluated by liquid chromatography with tandem mass spectrometry (LC-MS/MS) and inductively coupled plasma-mass spectrometry (ICP-MS). Results showed that AgNPs-priming at all tested concentrations significantly increased the content of essential amino acids for several folds in cabbage leaves, including alanine, aspartic acid, glutamine, glutamic acid, histidine, isoleucine, leucine, lysine, phenylalanine, proline, serine, threonine, tyrosine, and valine. Meanwhile, AgNPs-priming (40 mg/L) significantly increased iron (Fe) content by 23.8% in cabbage leaves. Ag did not bioaccumulate in edible tissues, indicating the bio-safety of AgNPs-priming. These results suggest that AgNPs-priming is a low-cost and eco-friendly approach to increase crop yield and nutritional quality.

The elucidation of precise structure of fucoidan is essential for understanding their structure-function relationship and promoting the development of marine drugs. In this work, we firstly reported the oligosaccharide mapping of fucoidan from Holothuria floridana using a combination of hydrothermal depolymerization, hydrophilic interaction liquid chromatography (HILIC) coupled with electrospray mass spectrometry (ESI-FTMS) and high energy collision-induced dissociation (HCD-MS/MS) and 2D NMR analysis. With careful selection of fully deprotonated molecular ions of fucoidan oligosaccharides and their NaBD4 reduced alditols, HILIC-ESI-HCD-MS/MS provided structurally relevant glycosidic product ions with no sulfate loss for definitive assignment of sequence and sulfation pattern of all the oligosaccharides and their isomers from dp2 to dp7 from hydrothermal depolymerization. The oligosaccharide mapping clarified the structure of fucoidan with various oligosaccharide domains with 2,4-di-O-sulfated and 2-O sulfated fucose residues.

Di-n-butyl phthalate (DBP) as a plasticizer is widely used in food and chemical industries. It is harm to human health when it appeared in food and water. A novel near-infrared (NIR) fluorescence molecularly imprinted sensor based on CdTe quantum dots and zeolite imidazolate framework-67 was developed with a sol–gel polymerization method for rapid and sensitive determination of DBP in foodstuff rapidly (only in 1.5 min). The fluorescence imprinted sensor provided a rapid detection method for DBP in the linear response concentration range of 0.05–18.0 μM with a low detection limit of 1.6 nM. Compared with previous fluorescence imprinted sensor, it behaved faster response speed and lower detection limit for determination of DBP. The fluorescence imprinted sensor was used to detect DBP in real samples successfully with satisfied recoveries of 97.2–106.4%, suggesting a potential application in food analysis.

A highly active electrocatalyst is synthesized by employing melamine assisted metal-organic framework as the precursor. By pyrolyzing the hybrid at 350–800 °C, the precursor can be easily transferred into abundant iron and nitrogen co-doped carbon skeleton. The microbial fuel cell doped with the above treated sample at 600 °C achieves the maximum power density 2229 ± 10 mW m−2, 257% and 36.6% higher than that of activated carbon and the control sample. The total resistance decreases by 53.8% from 18.16 Ω (activated carbon) to 8.39 Ω. The reaction process is testified to be four-electron transfer. X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy prove the coexistence of divalent copper and C3N4 and the incorporation of nitrogen into the network formed active sites. Thus, the ideal results make the pyrolyzed hybrid at 600 °C a promising catalyst in microbial fuel cell.

δ-Secretase, an age-dependent asparagine protease, cleaves both amyloid precursor protein (APP) and Tau and is required for amyloid plaque and neurofibrillary tangle pathologies in Alzheimer's disease (AD). However, whether δ-secretase activation is sufficient to trigger AD pathogenesis remains unknown. Here we show that the fragments of δ-secretase-cleavage, APP (586-695) and Tau(1-368), additively drive AD pathogenesis and cognitive dysfunctions. Tau(1-368) strongly augments BACE1 expression and Aβ generation in the presence of APP. The Tau(1-368) fragment is more robust than full-length Tau in binding active STAT1, a BACE1 transcription factor, and promotes its nuclear translocation, upregulating BACE1 and Aβ production. Notably, Aβ-activated SGK1 or JAK2 kinase phosphorylates STAT1 and induces its association with Tau(1-368). Inhibition of these kinases diminishes stimulatory effect of Tau(1-368). Knockout of STAT1 abolishes AD pathologies induced by δ-secretase-generated APP and Tau fragments. Thus, we show that Tau may not only be a downstream effector of Aβ in the amyloid hypothesis, but also act as a driving force for Aβ, when cleaved by δ-secretase.

The importance of the oxidizing capacity of reactive chlorine species, and the heterogeneous reactions of atmospheric pollution gases on the surface of particles has been well established in field observation, modeling simulation and laboratory exploration. However, less is known about the reactions of reactive chlorine on mineral particles. We studied the effect of Cl2 on the heterogeneous reaction of NO2 with γ-Al2O3 by using ion chromatography and positron annihilation lifetime spectroscopy. The presence of Cl2 can promote the uptake of NO2 on γ-Al2O3 at humid conditions. The probable explanations are that Cl2 rapidly reacts with NO2 on the γ-Al2O3 surface in the presence of adsorbed water, and nitrites, as the intermediate products during the heterogeneous reaction of NO2 on mineral dust, are immediately oxidized by adsorbed Cl2. In the positron annihilation lifetime spectroscopy experiment, a porous γ-Al2O3 was demonstrated by the relatively high fourth lifetime intensity. The increase in the number of anions (onto γ-Al2O3) when the reaction time was prolonged was a direct consequence of the decrease in the o-Ps intensity and the o-Ps lifetime, which illustrated that the heterogeneous reactions might occur on the porous surface of γ-Al2O3. Our results suggest that the oxidative effect of Cl2 on the heterogeneous conversion of NO2 to nitrogen-containing particles might have a significant contribution to the fine particle growth and to the unknown sources of nitrate observed in secondary inorganic aerosols.

To extend the practical applications of collagen, alternatives to mammalian sources are needed. In this study, acid-soluble collagen (ASC) and pepsin-soluble collagen (PSC) were extracted from the cuticle of Perinereis nuntia (Savigny), and their physicochemical features and structures were examined. The yields of ASC and PSC were 3.89% and 6.74%, respectively. The glycine contents of both collagens accounted for approximately one-third of the total amino acid residues, and the sum totals of proline and hydroxyproline in ASC and PSC were 212 and 214 residues/1000 residues, respectively. However, the proline hydroxylation rates of ASC and PSC were 84.0% and 83.6%, respectively. The maximum absorption peaks of both ASC and PSC were detected at 233 nm. Zeta potential studies indicated that ASC and PSC have a net zero charge at pH 4.89 and 4.95, respectively. Fourier-transform infrared spectroscopy, circular dichroism, and X-ray diffraction confirmed the triple helical structure of the collagen. The denaturation temperatures (Td) of ASC and PSC were 36.5 °C and 33 °C, respectively. Moreover, the collagens appeared to be loose, fibrous, and porous by scanning electron microscopy. These results suggested that collagen from the cuticle of Perinereis nuntia (Savigny) has potential commercial applications in the food, nutraceutical, and pharmaceutical industries.