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Increasing number of resistant bacteria have emerged with the overuse of antibiotics, which indicates that the bacterial infection has become a global challenge. Furthermore, the pollution of antibiotics to the environment has become a serious threat to public health. It is known that toxins produced by bacteria are the main cause of bacterial infections. Photothermal therapy is an effective antibacterial approach. However, the photothermal reagents cannot eliminate bacterial toxins, and even some anti-bacterial materials are toxic. Here, we synthesized a biomimetic recycled nanoparticle, red blood cell (RBC) membrane-coated Fe3O4 nanoparticles (RBC@Fe3O4), as an antibacterial agent. The RBC@Fe3O4 nanoparticles act as nano-sponges to trap toxins and then kill them all with a photothermal effect. We can describe this process simply as a battle between two armies. Our strategy is to disarm the "enemy" so that we can easily kill the "enemy" who has no power, which results in enhancing the bactericidal efficacy. The toxin of methicillin-resistant Staphylococcus aureus (MRSA) was absorbed by RBC@Fe3O4in vitro. In addition, in vivo studies proved that the RBC@Fe3O4 nanoparticles confer obvious survival benefits against toxin-induced lethality by absorbing the toxin of MRSA. Furthermore, using a mouse model of MRSA wound infection, the RBC@Fe3O4 nanoparticles with laser irradiation were found to have a superior wound-healing effect. Simultaneously, the RBC@Fe3O4 nanoparticles could be recycled in a simple way without affecting the bactericidal efficacy. The highly biocompatible and recyclable RBC@Fe3O4 biomimetic nanoparticles based on photothermal therapy and bacterial toxin adsorption strategy are promising for treating bacterial infections.

The perovskite solar cells (PSCs) based on cesium lead bromide (CsPbBr3) with outstanding environmental stability and low preparation cost are regarded as one of the most promising photovoltaic dev...

Nitrosamines have become a focus of considerable research because of their carcinogenicity and environmental universality. In this study, to effectively remove nitrosamines, biological acti...

The preparation of high-quality perovskite films with low grain boundaries and defect states is a prerequisite for achieving high-efficiency perovskite solar cells (PSCs) with good environmental stability. An effective additive engineering strategy has been developed for simultaneous defect passivation and crystal growth of CsPbBr3 perovskite films by introducing 1,3,5-triazine-2,4,6-triamine (melamine) into the PbBr2 precursor solution. The resultant melamine-PbBr2 film has a loose, large-grained structure and decreased crystallinity, which has a positive effect on the crystallization process of the perovskite as it retards the crystallization rate as a result of the interaction between melamine and lead ions. Additionally, the passivation by melamine gives a high-quality CsPbBr3 perovskite film with fewer grain boundaries, lower defect densities, and better energy level matching is achieved by multistep liquid-phase spin-coating, which greatly suppresses the nonradiative recombination resulting from the defects and promotes charge extraction at the interface. A champion power conversion efficiency as high as 9.65 % with a promising open-circuit voltage of 1.584 V is achieved for PSCs with an architecture of fluorine-doped tin oxide/c-TiO2 /m-TiO2 /melamine-added CsPbBr3 /carbon-based hole-transporting layer. Furthermore, the unencapsulated melamine-added CsPbBr3 PSC shows superior thermal and humidity stability in ambient air at 85 °C or 85 % relative humidity over 720 h.

The favorable contact and matching energy level at the electrode/perovskite interface as well as the high-quality perovskite film are prerequisites for high photovoltaic performance perovskite solar cells (PSCs). Herein, an innovative interface engineering strategy has been proposed to modify TiO2 as well as the perovskite film simultaneously by introducing ammonium chloride (AC), which not only improves the contact and energy level matching at the TiO2/perovskite interface but also provides a high-quality perovskite film with larger grain size by regulating the crystallization kinetics of CsPbBr3. Furthermore, chlorine anions in AC tend to combine with TiO2 to passivate its surface defects; the ammonium cation can bond with the uncoordinated ionic defects of perovskite. As a result, a remarkably enhanced charge extraction and retarded charge recombination within inorganic CsPbBr3 PSCs is acquired through the interface engineering of AC, and the power conversion efficiency of the modified device is increased from the original 6.59% to 9.60%. By compensating the energy level at the perovskite/carbon interface by setting an efficient hole-transporting layer of zinc phthalocyanine (ZnPc), the best efficiency up to 10.12% was achieved for the device with AC and ZnPc interface modification, which is much higher than 7.87% efficiency for the ZnPc-only PSCs, further demonstrating the important positive effects of AC modification on device performance. Moreover, the optimized device without any encapsulation presents an exceptional long-term stability under persistent attack by 80% RH air atmosphere at 25 °C for 720 h.

Sensitive detection of β-galactosidase (β-gal) is of great significance for early diagnosis of ovarian cancer. Fluorescent probes for detecting β-gal have received great interest due to the non-invasiveness, excellent sensitivity, high temporal, and superior spatial resolution. However, most reported fluorescent sensors for β-gal suffer from aggregation caused quenching effect when accumulated, and cannot discriminate β-gal from other species, especially, Escherichia coli β-gal. Herein, we report the first aggregation-induced emission (AIE)-active fluorescent probe HBTTPAG, which achieves species-selective detection of β-gal. Probe HBTTPAG can discriminate Aspergillus oryzae β-gal from Escherichia coli β-gal, with high sensitivity (detection limit of 3.7 × 10-3 UmL-1), superior selectivity and low cytotoxicity. Furthermore, HBTTPAG is utilized to visualize endogenous β-gal in lysosomes of SKOV-3 cells, as well as to detect β-gal activity in ovarian cancer tissues. Notably, owing to the AIE-active, HBTTPAG realizes long-term (12 h) tracking β-gal in ovarian cancer cells. This work provides a promising method for species-selective detection of β-gal in preclinical.

Aiming at the harmful gas pollutants of low concentration sulfur dioxide and fluoride in electrolytic aluminum flue gas, the process of fluorine and sulfur removal was simulated by NaOH-CO2 gas–liquid absorption system, and the influence of operation and structure parameters such as gas flow rate, liquid flow rate, size, and type of filler on gas-liquid mass transfer process was explored. The results show that the gas flow rate is 1.5–2.0 m3/h, the liquid flow rate is 10–12 m3/h, and the filler is a Bauer ring with the nominal diameter (DN) of 16 mm, the gas–liquid mass transfer effect is the best and the maximum CO2 utilization rate is about 46%. According to the simulation results, when ammonia system is used to absorb sulfur dioxide and hydrogen fluoride, the concentration of sulfur dioxide and hydrogen fluoride can be reduced to 42 mg/m3 and 0.8 mg/ m3, respectively.

Background Tick bites severely threaten human health because they allow the transmission of many deadly pathogens, including viruses, bacteria, protozoa, and helminths. Pruritus is a leading symptom of tick bites, but its molecular and neural bases remain elusive. Objectives This study sought to discover potent drugs and targets for the specific prevention and treatment of tick bite–induced pruritus and arthropod-related itch. Methods We used live-cell calcium imaging, patch-clamp recordings, and genetic ablation and evaluated mouse behavior to investigate the molecular and neural bases of tick bite–induced pruritus. Results We found that 2 tick salivary peptides, IP defensin 1 (IPDef1) and IR defensin 2 (IRDef2), induced itch in mice. IPDef1 was further revealed to have a stronger pruritogenic potential than IRDef2 and to induce pruritus in a histamine-independent manner. IPDef1 evoked itch by activating mouse MrgprC11 and human MRGPRX1 on dorsal root ganglion neurons. IPDef1-activated MrgprC11/X1 signaling sensitized downstream ion channel TRPV1 on dorsal root ganglion neurons. Moreover, IPDef1 also activated mouse MrgprB2 and its ortholog human MRGPRX2 selectively expressed on mast cells, inducing the release of inflammatory cytokines and driving acute inflammation in mice, although mast cell activation did not contribute to oxidated IPDef1–induced itch. Conclusions Our study identifies tick salivary peptides as a new class of pruritogens that initiate itch through MrgprC11/X1-TRPV1 signaling in pruritoceptors. Our work will provide potential drug targets for the prevention and treatment of pruritus induced by the bites or stings of tick and maybe other arthropods.

An approach based on multifunctional fluorescent magnetic nanoparticles was proposed for the enrichment and identification of Alicyclobacillus spp. in apple juice simultaneously. The prepared Fe3O4 magnetic particles (MNPs) were modified by the sol-gel process and a silica shell was formed to improve the reactivity, and then the obtained MNPs@SiO2-SH nanoparticles were conjugated with Thioglycolic acid functionalized CdTe/CdS QDs via thiols chemistry. The characteristic evaluation results indicated that the MNPs-QD nanocomposites exhibited good magnetic properties and optical characterization. The polyclonal anti-Alicyclobacillus IgG antibody was immobilized onto the surface of MNPs-QD materials via esterification reactions. The maximum antibody immobilization capacity was 119.62 μg/mg and the adsorption reaction could be accomplished in 60 min. The adsorption process could be represented by Langmuir model and pseudo-second order kinetics equation, respectively. Based on the high immunocapture efficiency and sensitive fluorescence characteristics, the obtained MNPs-QDs-antibody conjugates could be applied to recognize the contamination of Alicyclobacillus spp. and a quantitative analysis method was established for target cells detection. The minimum quantitative limit was 104 CFU (colony forming unit)/mL and the testing process could be completed in 90 min. The results indicated that the MNPs-QDs-antibody conjugates can be successfully applied for immunocapture and detection of Alicyclobacillus spp. in apple juice. That is to say, the developed MNPs-QDs-antibody conjugates have exhibit more attractive and great potential for the immunocapture and recognition of target bacteria, fully demonstrated a new method for enrichment and rapid detection of Alicyclobacillus spp. in fruit juices.

Floodgates operation is one of the primary means of flood control in lake development. However, knowledge on the linkages between floodgates operation and nitrogen transformation during the flood season is limited. In this study, water samples from six sampling sites along Lake Xingkai watershed were collected before and after floodgates operation. The causal relationships between environmental factors, bacterioplankton community composition and nitrogen fractions were determined during flood season. We found that concentrations of nitrogen fractions decreased significantly when the floodgates were opened, while the concentrations of total nitrogen (TN) and NO3- increased when the floodgates had been shut for a period. Further, we proposed a possible mechanism that the influence of floodgates operation on nitrogen transformation was largely mediated through changes in dissolved organic matter, dissolved oxygen and bacterioplankton community composition as revealed by structural equation modeling (SEM). We conclude that floodgates operation has a high risk for future eutrophication of downstream watershed, although it can reduce nitrogen content temporarily. Therefore, the environmental impacts of floodgates operation should be carefully evaluated before the floodwaters were discharged into downstream watershed.

Since there is a symbiotic and competitive relationship between microorganisms in the same ecological niche, fungal defensins have been found to be important resources for antimicrobial peptides. Here, a fungal defensin, triintsin, was characterized in a clinical isolate of Trichophyton interdigitale from a patient with onychomycosis. The comparison of its genomic and mRNA sequences showed the gene organization and structure of three coding exons separated by two introns. The precursor peptide of triintsin contained 85 amino acid residues, which were composed of three parts including an N-terminal signal domain of 21 residues, a pro-peptide of 47 residues that ended at lysine-arginine and a mature peptide of 38 residues at the C-terminus. The 3D-structure established by homology modeling revealed that triintsin presented a representative typical cysteine-stabilized α-helical and β-sheet fold. The reductive linear peptide of triintsin was obtained by chemical synthesis. After cyclization to form three pairs of disulfide bonds, the oxidative-type peptide displayed broad-spectrum antimicrobial activity against both gram-positive and gram-negative bacteria but also showed anti-fungal activity. Moreover, triintsin can effectively inhibit the growth of clinical strains. Altogether, the peptide is a human pathogenic fungus-derived defensin with broad-spectrum antimicrobial activity.

A simple and rapid method was developed using microwave-assisted extraction (MAE) combined with HPLC–DAD–ESI–MS/MS for the simultaneous extraction, identification, and quantification of phenolic compounds in Eclipta prostrata , a common herb and vegetable in China. The optimized parameters of MAE were: employing 50% ethanol as solvent, microwave power 400 W, temperature 70 °C, ratio of liquid/solid 30 mL/g and extraction time 2 min. Compared to conventional extraction methods, the optimized MAE can avoid the degradation of the phenolic compounds and simultaneously obtained the highest yields of all components faster with less consumption of solvent and energy. Six phenolic acids, six flavonoid glycosides and one coumarin were firstly identified. The phenolic compounds were quantified by HPLC–DAD with good linearity, precision, and accuracy. The extract obtained by MAE showed significant antioxidant activity. The proposed method provides a valuable and green analytical methodology for the investigation of phenolic components in natural plants.

The purpose of the present study was to explore the protective effect and functional mechanism of ginkgolide K (GK: C20H22O9) on cerebral ischemia. SH-SY5Y cells were exposed to oxygen-glucose deprivation (OGD) to simulate an ischemic model in vitro. Cell viability, reactive oxygen species (ROS), nuclear staining with Hoechst 33258 and mitochondrial membrane potential were detected following 4 h of exposure to OGD. Subsequently, the expression levels of the apoptosis-related proteins, caspase-9, caspase-3, Bcl-2, Bax, p53 and c-Jun, as well as the mitogen-activated protein kinases (MAPKs) signaling molecules were detected by western blot analysis. GK significantly elevated the cell viability and decreased the generation of ROS and the number of apoptotic cells in a dose-dependent manner. Furthermore, GK markedly decreased the protein expression levels of p-p38, p-JNK, p-p53, p-c-Jun and the expression levels of Bcl-2, Bax, cleaved caspase-9 and caspase-3. In conclusion, GK demonstrated a neuroprotective effect on the simulated cerebral ischemia in vitro, and this effect was mediated through the inhibition of the mitochondria-mediated apoptosis pathway triggered by ROS-evoked p38 and JNK activation.

The pollution of heavy metals in fruit juice is still increasing and becoming a significant food safety issue worldwide nowadays. In this work, twelve strains of lactic acid bacteria (LAB) were evaluated for the biomass and their capability to adsorb Cd2+ and Pb2+. One strain of LAB capable of efficiently adsorbing heavy metals in apple juice was screened. The obtained LAB was functionalized by magnetic Fe3O4 nanoparticles (MNPs) and modified by Ethylenediaminetetraacetic acid dianhydride (EDTAD) for generation EDTAD-MNPs-LAB (EMB) adsorbent, which was further characterized by Scanning electron microscopy, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. The results indicated that the strain of LAB was successfully functionalized and modified by MNPs and EDTAD. The maximum adsorption capacity of EMB adsorbent for Cd2+ and Pb2+ in apple juice was 0.57 mg/g and 0.17 mg/g, respectively. The EMB adsorbent could be rapidly separated from the sample solution with the help of magnetic field and the adsorption process has no significant impact on the quality of fruit juice. The regeneration experiments revealed that the EMB adsorbent could be successfully reused. The research provides a new insight and strategy for the effective adsorption and removal of heavy metals from juice.

Carbon-based hole-transporting material (HTM)-free CsPbBr3 perovskite solar cells (PSCs) provide new opportunities for promoting the commercial application of PSCs because of the low cost, simple preparation process and excellent stability under various extreme conditions. One of the remaining problems for inorganic CsPbBr3 PSCs is the low power conversion efficiency (PCE) due to the large energy level difference and inefficient hole extraction at CsPbBr3/carbon interface. Herein, polyaniline/graphite (PANi/G) composites are incorporated into carbon electrode to tailor work function and to improve hole-selectivity of back electrode for enhanced energy level alignment and interfacial hole extraction, leading to a remarkably reduced energy loss and charge recombination. The HTM-free CsPbBr3 PSC based on carbon-PANi/G electrode achieves a PCE of 8.87%, which is increased by 43.8% in comparison with 6.17% for the control device. Moreover, the unencapsulated device shows excellent long-term moisture tolerance with the initial PCE maintaining 93.5% even exposure to air atmosphere with 80% RH at 25 °C over 50 days. The successful improvement of energy level alignment and charge extraction in device by directly incorporating PANi/G composites into carbon electrode offers a promising strategy in developing low-cost and efficient HTM-free PSCs.

An efficient ultrasonic-assisted extraction using ultrasonic probe system (UPAE) was developed for the extraction of wedelolactone (WEL) and antioxidant polyphenols from Eclipta prostrate. A central composite design and response surface methodology (RSM) were used to optimize the UPAE. The key parameters considered for the UPAE included solvent type, temperature, ultrasonic power, solvent to material ratio and extraction time. The dependent variables included the yield of WEL, total phenolic content (TPC) and scavenging activity of DPPH radical. For simultaneously maximizing the three responses, the optimal conditions were 48% ethanol–water mixture as solvent, temperature of 40 °C, ultrasonic power of 90 W, solvent to material ratio of 50 mL/g and extraction time of 11 min. The predicted values from the developed quadratic polynomial equations were in close agreement with the actual experimental values. The TPC and %DPPH of the optimized UPAE were significantly higher than those of ultrasonic-assisted extraction using ultrasonic bath, heat reflux extraction and Soxhlet extraction. Compared to conventional extraction methods, UPAE provided higher extraction efficiency and offered many advantages such as reduction of time and energy for extraction. The developed UPAE appears to be a green method and have great potential for the extraction of active components and antioxidants from natural products.