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Solar water evaporation technology has become one of the promising ways for seawater desalination by excellent energy capture and efficient solar-thermal conversion. However, some challenges still restrict its further industrial development, such as low flexibility, non-portability, and insufficient energy utilization, salt crystallization problems. In this work, hierarchical MoS2 nanosheets coupled with MXene (MoS2-MXene) is constructed and formed into a film with foldability and portability for solar water evaporation. Improved evaporation rate (2.5 kg m−2 h−1) is observed due to enhanced energy capture from a folded 3D solar evaporation system. Meanwhile, the outstanding evaporation performance (3.2 kg m−2 h−1) is realized because of gradient heating from a hydrophobic MoS2-MXene@PF (MoS2-MXene@Paraffin) under one sun. During the evaporation of high-concentration NaCl solution (20 wt%), the hydrophobic layer is observed to become a salt crystallization site for salt generation. After long-term and multiple testing, no salt crystallization was found at the evaporation site, maintaining a stable evaporation rate. More interesting, MoS2-MXene@PF can be also succeeded as a solar thermal pack for storing heat through the phase change material paraffin (PF). This work provides a new solution to realize excellent energy capture for solar desalination and solar thermal storage.

Engineering cell-derived nanovesicles with active-targeting ligands is an important strategy to enhance the targeting efficiency. However, the enhanced binding capability to targeting cells also leads to the binding with nontarget cells that share the same biomarkers. DNA-based logic gate is a kind of molecular system that responds to chemical inputs by generating output signals, and the relationship between the input and the output is based on a certain logic. Thus, the DNA-based logic gate could provide a new approach to improve the delivery efficiency of the nanovesicle. In this work, we developed a DNA logic-gated module that coupled two tumor cell-targeting factors (e.g., low pH and a tumor cell biomarker) in a Boolean manner. Immobilization of this module on the surface of the nanovesicle enables the nanovesicle to sense tumor cell-targeting factors and regard these cues as inputs AND logic gate. With the guide of DNA-based logic gate, gold carbon dots (GCDs) encapsulated within nanovesicles were delivered into target cells, and then the intracellular redox status variation was reflected by fluorescence change of GCDs. Overall, we developed DNA logic-gated nanovesicles that contract different targeting factors into a unique tag for target cells. This facile functionalization strategy can pave the way for constructing smart nanovesicles and would broaden their application in the field of precision medicine and personalized treatment.

Solar-driven steam generation is anticipated as one of the most promising and inventive technologies to address the primitive issues of water shortage. Although extensive attempts have been made to...

Ferric(III) ions (Fe3+) are one of the most abundant metal ions in environmental and biological systems. The determination of Fe3+ has attracted great attention for healthcare concerns. In this work, we have developed a novel fluorescence method for the sensing and intracellular imaging of Fe3+ based on the prepared red-emissive carbon nanodots. The nanoprobes are synthesized via a microwave method using ammonium fluoride and o-phenylenediamine as carbon precursors, which exhibit excellent optical properties and low toxicity. More importantly, the carbon nanodots show high selectivity towards Fe3+ against other interfering ions. The sensitivity is also high with the limit of detection as low as 0.05 μM. Meanwhile, the carbon nanodots have been successfully used for fluorescence imaging of cells and could be quenched by intracellular Fe3+. These results suggest that the red-emissive carbon nanodots have diverse potential utilities in biomedical fields.

Solar-driven interfacial evaporation is an efficient and economical technology for converting low-grade solar energy to high-grade steam energy. However, solar water evaporators that exhibit both high water vapor generation ability and multifunction water purification are still less reported. Herein, the 2D Ti3C2Tx (MXene) is tactfully assembled into 3D porous macroscopic aerogel monoliths by a graphene oxide (GO)-assisted process as an independent solar-driven interfacial evaporator for efficient and all-around water purification. GO is weakly reduced by MXene to reduced graphene oxide (RGO) during the process, leading to a self-enhanced photothermal conversion regulation. The floating GO/MXene aerogel (GMA)-based evaporator achieves high solar evaporation efficiency up to 90.7% with an evaporation rate of 1.27 kg/m2 h under one sun irradiation. Several simple prototypes have been designed and implemented as demonstrators of practical water purification in both summer and winter. The portable GMA could realize all-around water purification for rapid and effective elimination of salting, organic pollutants, bacterium and other contaminants as a personalized water purification system.

Solar evaporation has emerged as a facile and attractive technology for clean water production, desalination, and organic solvent purification by virtue of abundant solar energy. However, developing a high-performance, environment friendly, and scalable solar evaporator remains a significant challenge. Herein, a one-step, low-cost, and easy-to-manufacture synthesis of a three-dimensional macroporous solar steam generator is reported based on polypyrrole coated natural latex (PPy-NL) foam, offering a sustainable solution to the ever-growing issues of the energy and water crises. The as-prepared foam exhibits good wettability, acid and alkali resistance, high mechanical strength, low thermal conductivity (0.2257 W m–¹ K–¹) and excellent light absorption of ∼95% owing to the introduction of PPy coating. Among polymer photothermal materials, PPy-NL foam gives a vapor generation rate of 1.76 kg m–² h–¹ with a superb solar thermal conversion efficiency of 98% under 1 sun illumination. Furthermore, PPy-NL foam can be directly used to purify various types of wastewater and organic solvent with a high rejection of ions (nearly 100%), oil, and dye. This simple fabrication process with renewable polymer resources and photothermal materials provides a fundamental guidance and practical application value toward developing high-performance solar evaporation technologies for remote areas and individuals.

Inflammatory bowel disease (IBD) is a complex inflammatory disorder of the digestive tract with dysregulated innate and adaptive immune responses. Dendritic cells (DC), the most important antigen presenting cells, act as bridges connecting the adaptive and innate immune systems, and play a crucial role in the regulation of local homeostasis in the gut and are also essential mediators in the initiation and development of intestinal inflammation. Our recent study found that sauchinone (SAU) was able to ameliorate experimental colitis in mice by restraining Th17 cell differentiation and their pathogenicity. Here, we found that SAU significantly inhibited LPS-induced DC activation. Moreover, SAU suppressed the ability of LPS-primed DC to induce Th1/Th17 cell differentiation, but SAU-treated DC up-regulated their ability to initiate Foxp3+ Treg cell generation. Of note, we found that genetical ablation of Blimp-1 in DC markedly abrogated the SAU suppression of pro-inflammatory cytokine or promote immunomodulatory molecule production by DC. Blimp-1 deficiency boosted the ability of DC to polarize naive CD4+ T cells into Th1/Th17 cell lineages. SAU failed to alleviated DSS-induced colitis in mice with Blimp-1-deficient DC. Our results shed new lights on the mechanisms of how SAU regulates DC biology and intestinal inflammation.

Solar-driven water evaporation is deemed to be a green and sustainable strategy to cope with the global freshwater crisis. However, effective water evaporation to achieve high water yield in practi...

The simulation of the native bone matrix formation process is crucial for the construction of the cellular microenvironment for bone regeneration. However, it is still challenging to design bioactive materials that simultaneously mimic the composition and dynamic mineralization process of the bone matrix, let alone realize osteoinduction by a biomimetic dynamic microenvironment. In this study, we prepared a biomimetic mineralizable collagen hydrogel (CAV) and explored the effects of a dynamic mineralized matrix on the osteogenesis of stem cells both in vitro and in vivo. We showed the feasibility of the biomimetic CAV hydrogel to induce mineralization in simulated media including simulated body fluid (SBF), glycerol phosphate calcium salt hydrate (CaGP) solution and cell co-cultured systems. The participation of cells in the mineralization process is more likely to induce matrix remodeling due to the synergistic effects of CAV mineralization and cellular secretion, resulting in higher matrix strength. We also demonstrated that the biomimetic mineralized hydrogel could up-regulate osteogenic genes and protein expression of bone marrow mesenchymal stem cells (BMSCs), thus enhancing osteogenesis in vivo. The interactions between the mineralizable hydrogel and cells play an important role in regulating dynamic matrix mineralization and osteogenesis. Our findings prove that the biomimetic mineralizable hydrogel is a promising candidate for implantable orthopedic applications and provides essential implications for the future design of materials for bone regeneration.

Polymer dots are extensively studied in the fields of catalysis, energy storage, light-emitting devices, biomedicine and engineering, and fluorescent sensors. In this paper, we report on synthesis of a new type of sulfur-containing polymer dots (SPDs) through an atomic transfer radical polymerization method. The SPDs exhibit a maximum photoluminescence at 378 nm under excitation wavelength of 280 nm. The deep-blue luminescence of SPDs may be attributed to self-passivation of SPDs by polyethylene glycol oligomers which create surface states between π* band and π energy level. Also, the SPDs show a highly selective sensitivity to Fe3+ in a mixed metal-ion solution containing Ag+, Cu2+, Hg2+, Cd2+, Pb2+, Cr3+, and Fe3+ with every metal-ion concentration set at 50 μmol L‒1. The detection limit of Fe3+ by SPDs is determined to be 1.7 μM at a signal-to-noise ratio of 3, lower than the maximum of Fe3+ tolerance (5.4 μM) in drinking water permitted by the U.S. Environmental Protection Agency.

Alkaline phosphatase (ALP) and phosphoprotein participation in collagen mineralization is one of the most important physiological processes of bone formation. Simulating the natural mineralization process with the involvement of ALP and phosphoproteins is a powerful tool for the preparation of bone repair scaffolds. Searching for compatible approaches to chemically bond ALP with collagen molecules and introducing phosphoprotein-like molecules into a collagen network is the challenge of the day. Here, we synthesized alkaline phosphatase methacrylamide (ALP-MA) via amidation reaction to enable ALP to be grafted uniformly into the photo-cross-linking collagen gel, achieving homogeneous enzymatic mineralization. Furthermore, vinylphosphonic acid (VAP), a phosphoprotein-like molecule containing phosphonate groups, was successfully introduced on collagen molecules through photo-cross-linking, playing the role of a phosphoprotein for inducing mineralized CaP clusters deposited on the collagen backbone. Hence, a hydrogel termed CAV was synthesized via photochemical reaction among collagen methacrylamide (Col-MA), ALP-MA, and VAP (active mineral bonding site) for in situ mineralization. We found that the binding between the collagen network and CaP clusters would lead to the generation of mechanically enhanced mineralized collagen hydrogel. Encapsulated bone marrow stromal cells (BMSCs) exhibited good growth and proliferation in the in situ enzymatic mineralization process. Additionally, the simulated mineralization system is highly favorable for micropatterned structure construction and 3D bioprinting. In brief, we designed a novel approach to effectively simulate the physiological mineralization process of bone formation. The approach, incorporating great photo-cross-linking performance and enzymatic mineralization activity, was beneficial for in situ cell encapsulation and excellent cell-compatible 3D printing, holding great promise for bone tissue engineering research.

Ethnopharmacological relevance Astragali radix (Huang Qi, HQ), a well-known Chinese herbal medicine, is widely coadministered with many other drugs for treating diseases. The potential herb–drug interactions (HDIs) possibly occur during the combination therapy. P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP) are the crucial targets that mediate the production of HDIs. We previously observed that HQ and its three main bioactive compounds, including Astragaloside IV (AS-IV), calycosin (CS) and formononetin (FMNT), could significantly induce the expression of P-gp and BCRP in HepG2 cells in vitro. However, their modulations on the function of P-gp and BCRP remain unknown; their impact on these two proteins expression in vivo is not clear; the exact regulatory mechanism has also not yet been explored. Aim of the study This study aimed to investigate the impact of HQ, AS-IV, CS and FMNT on P-gp and BCRP in vivo, and the exact regulatory mechanism involved. The effects of HQ and these compounds on the function of P-gp and BCRP were also studied. Materials and methods Wild-type C57BL/6 mice and nuclear factor E2-related factor-2 knockout (Nrf2−/−) C57BL/6 mice were orally treated with HQ, AS-IV, CS or FMNT. The protein levels of P-gp and BCRP in the liver of mice were measured by using Western blot and immunohistochemistry. The mRNA levels were measured by using real-time PCR. The activation of the drugs on the antioxidant response element (ARE)–luciferin activity was studied by using reporter assay in a stably transfected HepG2-C8 cells. The efflux activity of P-gp and BCRP in HepG2 cells were tested by using flow cytometer with typical probes. Results HQ, AS-IV, CS and FMNT significantly upregulated the P-gp and BCRP expression in the liver of wild-type mice. The induction was significantly reversed in the Nrf2−/− mice. HQ and these compounds significantly increased the Nrf2 expression in wild-type mice. HQ and these compounds also markedly enhanced the ARE-luciferin activity and promoted the nuclear translocation of Nrf2 in cells. Besides, HQ and these compounds significantly enhanced the efflux activity of P-gp and BCRP, and increased the intracellular ATP levels. Conclusions Our results proved that HQ and its main bioactive compounds could induce the P-gp and BCRP expression through the activation of the Nrf2-mediated signaling pathway. HQ and these compounds also significantly enhanced the efflux activity of P-gp and BCRP, and the increased intracellular ATP levels were likely involved in the increased P-gp and BCRP function. These results suggested that potentially HDIs likely occurred when HQ was used concomitantly with other drugs that are substrates of P-gp and BCRP.

Background Chronic obstructive pulmonary disease (COPD) is an important risk factor for developing lung cancer. Aged citrus peel (chenpi) has been used as a dietary supplement for respiratory diseases in China. Objective To explore the mechanism and candidate compounds of chenpi preventing COPD and its progression to lung cancer. Methods The active components and potential targets of chenpi were retrieved from the Traditional Chinese Medicine Systems Pharmacology (TCMSP) database. Disease-associated targets of COPD and lung cancer were collected in the Gene Cards and TTD database. The component-target network and PPI network were constructed using the Cytoscape 3.8.0 software. David database was used for GO and KEGG enrichment analysis. The main active components were verified by using the autodock Vina 1.1.2 software. Mouse lung cancer with COPD was induced by cigarette smoking (CS) combined with urethane injection to confirm preventing the effect of hesperetin (the candidate compound of chenpi) on COPD progression to lung cancer and its underlying mechanisms. Results The network analysis revealed that the key active components of chenpi (nobiletin, naringenin, hesperetin) regulate five core targets (AKT1, TP53, IL6, VEGFA, MMP9). In addition, 103 potential pathways of chenpi were identified. Chenpi can prevent COPD and its progression to lung cancer by getting involved in the PI3K-Akt signaling pathway and MAPK signaling pathway. Molecular docking indicated that hesperetin had better binding activity for core targets. In mouse lung cancer with COPD, treatment with hesperetin dose-dependently improved not only lung tissue injury in COPD but also carcinoma lesions in lung cancer. Meanwhile, hesperetin could suppress the protein expression of AKT1, IL6, VEGFA, MMP9 and up-regulate the protein expression of TP53, and thus reduced the risk of COPD progression to lung cancer. Conclusion Hesperetin is a candidate compound of chenpi that helps in preventing COPD and its progression to lung cancer by regulating AKT1, IL6, VEGFA, MMP9 and TP53.

Buildings consume many resources and generate greenhouse gases during construction. One of the main sources of greenhouse gases is carbon emission associated with buildings. This research is based on the computing rule of carbon emission at the materialization stage. By taking the features of green construction into consideration, quantitative analysis on construction carbon emission was undertaken via Life Cycle Assessment (LCA). Making use of Vensim (a system dynamics software package), we analyzed the amount of carbon emission at the materialization stage and determined the major subsystems affecting the carbon emission, then took into comprehensive consideration the differences of each subsystem&rsquo, s carbon emission under different construction technologies. Under the mechanism of carbon trade at the materialization stage, the total price of carbon trades remains unchanged, while the trading price of each subsystem is adjusted. Under these conditions, a coefficient for step-wise increases in carbon price was proposed. By establishing such a system of gradient prices, construction companies are encouraged to adopt high-efficiency emission reduction technologies. Meanwhile, the system also provides a reference for the formulation of price-based policies about buildings&rsquo, carbon trading, and accelerates the process of energy conservation and emission reduction in China and the world at large.

Cell-cell communication plays a vital role in biological activities; in particular, membrane-protein interactions are profoundly significant. In order to explore the underlying mechanism of intercellular signaling pathways, a full range of artificial systems have been explored. However, many of them are complicated and uncontrollable. Herein we designed an artificial signal transduction system able to control the influx of environmental ions by triggering the activation of synthetic transmembrane channels immobilized on giant membrane vesicles (GMVs). A membrane protein-like stimulator from one GMV community (GMVB) stimulates a receptor on another GMV community (GMVA) to release ssDNA messengers, resulting in the activation of synthetic transmembrane channels to enable the influx of ions. This event, in turn, triggers signal responses encapsulated in the GMVA protocell model. By mimicking natural signal transduction pathways, this novel prototype provides a workable tool for investigating cell-cell communication and expands biological signaling systems in general as well as explores useful platforms for addressing scientific problems which involve materials science, chemistry, and medicine.

Dendritic spines of excitatory neurons undergo activity-dependent structural and functional plasticity, which are cellular correlates of learning and memory. However, mechanisms underlying the rapid morphological changes immediately after NMDAR-mediated Ca2+ influx into spines remain poorly understood. Here we report that endophilin A1, a neuronal N-BAR protein, orchestrates membrane dynamics with actin polymerization to initiate spine enlargement in the induction phase of long-term potentiation (LTP). Upon LTP induction, Ca2+/calmodulin enhances its binding to both membrane and p140Cap, a cytoskeleton regulator. As a result, endophilin A1 rapidly associates with the relaxed plasma membrane and promotes actin polymerization, leading to acute expansion of spine head. Moreover, not only the p140Cap-binding, but also calmodulin- and membrane-binding capacities of endophilin A1 are required for LTP and long-term memory. Thus, endophilin A1 functions as calmodulin effector to drive spine enlargement in response to Ca2+ influx in the initial phase of structural plasticity.

Surface oxidized carbon nanotubes (oCNTs) were quite stable for the selective reduction of nitrobenzene, while notable deactivation was observed for the un-oxidized sample (rCNTs). The adsorption of N-containing compounds had a negligible effect, but the formation of a carboxyl group and anhydride was mainly responsible for the deactivation of rCNTs.

Assessment of microbial viability plays a key role in human health protection. Optical imaging based on fluorescent dyes is a simple and convenient way to assess microbial viability. However, it is still a challenge to obtain stable, nontoxic and low-cost dyes. Herein, we prepared a nitrogen and phosphorus co-doped carbon nanodots (N, P-CDs) via a one-step solvothermal method. The prepared CDs possess plenty of functional groups and exhibit high stability, good biocompatibility, excellent photoluminescent and low toxicity. Especially, the properties of high quantum yield (89.9%) and highly negative surface charge (−41.9 mV) make the prepared N, P-CDs ideal materials for microbial differentiation. Compared with commercial dyes, our CDs are more stable, cost less, which can rapidly distinguish dead microorganisms from living ones with higher specificity.

The authors are presenting the application of Fe3O4@Ag nanocomposites to a highly sensitive and selective analysis of hydrogen peroxide (H2O2). The morphology and structure of the synthesized porous Fe3O4 nanoparticles and Fe3O4@Ag nanocomposites are well-characterized by scanning electron microscopy (SEM), X-ray powder diffraction (XRD), UV–vis absorption spectrum, etc. The nanocomposites can be facilely modified on the magnetic glassy carbon electrode, which also exhibit a sharp silver stripping peak owing to the loaded Ag nanoparticles. Since an autocatalytic oxidation reaction of Ag nanoparticles occurs with the existence of H2O2, the peak current intensity is suitable to track H2O2 levels. The analytical performance is evaluated by the technique of linear sweep voltammetry, which shows a linear range from 0.5 to 20 μM. The limit of detection is as low as 0.16 μM. The detection can be completed in 5 min, which is quite fast and convenient. In addition, an electrochemical track of H2O2 released from li...

For an ideal biomimetic microenvironment to realize reliable cartilage regeneration, the ability to induce mesenchymal stem cell (MSCs) differentiation along the chondrogenic lineage and prevent further dedifferentiation is expected. With native bioactivity, collagen has been proved to be preferential for inducing the chondrogenic differentiation of MSCs. However, the phenotypic maintenance of differentiated chondrocytes in a collagen matrix is still a challenge. Actin traction, which causes drastic contraction of the collagen matrix, is frequently observed and might be an important factor that affects cell fates including chondrogenic differentiation and phenotypic maintenance. In this study, photochemical modification was applied to acquire collagen hydrogels with improved mechanical strength and creep behavior. Accompanied by inherited bioactivity, the photo-crosslinked collagen hydrogel well supported the actin cytoskeleton functionalization while resisting the actin-mediated matrix contraction. Benefitting from this, the hydrogel system promoted MSCs proliferation and chondrogenic differentiation, and more importantly, prevented further dedifferentiation. By exploring the mesenchymal development-related signal transduction markers, it was revealed that the promoted chondrogenesis was achieved through inhibiting the over-expression of MAPK and Wnt/β-catenin signaling pathways that up-regulated dedifferentiated gene expression. The strategy of applying the hydrogel system to cartilage regeneration is foreseeable based on the positive heterotopic and orthotopic chondrogenic differentiation.

Theophylline is a common bronchodilator for the treatment of diseases like asthma, bronchitis and emphysema. However, it should be strictly used and monitored due to its toxicity when the concentration is above certain levels. In this work, an electrochemical biosensor for theophylline detection is proposed by recognition of RNA aptamer and gold nanoparticle (AuNP)-based amplification technique. First, RNA aptamer is splitted into two single-stranded RNA probes. One is hybridized with DNA tetrahedron and the resulted nanostructure is then immobilized onto a gold electrode; the other is modified on the surface of AuNPs which is also labeled with methylene blue (MB) as electrochemical species. The recognition process between the two RNA probes and theophylline causes the localization of AuNPs and the enrichment of MB on the electrode interface. A significant electrochemical response is thus generated which is related to the concentration of initial theophylline. This proposed aptasensor shows excellent sensitivity and selectivity which could also be applied in quantitatively detection of theophylline in serums samples.

This study presents a facile synthesis method for the preparation of positively charged N,S co-doped carbon nanodots with excellent optical properties, and it develops a selective method for fluorescent detection of living cancer cells. The specific recognition is due to the application of an aptamer sequence, which shows high affinity and specificity to target cells. The aptamer is firstly labeled with BHQ and wraps around the carbon nanodots, then it finally quenches the fluorescence emission of the carbon nanodots. For the sensitive and selective analysis of target cells, the cells are simply mixed with the carbon nanodot-aptamer nanoconjugates, which are then centrifuged at a low speed. The recognition reaction between aptamer and target cells releases the quencher from the surface of the carbon nanodots and the centrifugation process enables the recovery of fluorescence intensity of the suspension, which reflects the level of initial cancer cells. The developed method is simple, highly selective and cost-effective, thus, it may be further exploited in clinical applications in the future.

Alkaline phosphatase (ALP) is closely associated with many health disorders like liver diseases and bone diseases, which is a routine index of blood examination. In the current study, a fluorescent method for the detection of ALP is established based on poly(thymine)-templated selective formation of copper nanoparticles (CuNPs) and alkyne–azide cycloaddition “click” reaction. Generally, in the presence of ALP, l-ascorbic acid-2-phosphate is hydrolyzed, and the generated ascorbic acid reduces Cu2+ to Cu+, which further catalyzes alkyne–azide cycloaddition click reaction between two poly(thymine) segments. The two DNA fragments (18 thymine) are thus ligated, forming the DNA template (36 thymine), which is effective for the synthesis of CuNPs. Experimental results show that the fluorescence response of CuNPs increases with higher ALP concentration from 0.1 to 40 U/mL, and the limit of detection is as low as 0.05 U/mL. Furthermore, the proposed method is highly selective and is capable of detecting ALP in bio...

In alcoholic liver disease (ALD) research, animal models, as one of the most popular methods to explore pathology and therapeutic drug screening, show the limitations of expensive cost and ethic, as well as long modeling time. To minimize the use of animal models in ALD research, an artificial liver model has been developed by incorporating HepG2 cells into hydrogel matrix based on difunctional hyaluronan and collagen. And on this basis an alcohol-induced ALD model in vitro by adding alcohol in the engineering process has been established. Results showed that the construct exhibited a simulated synthetic and metabolic liver function thanks to the bionic fibrillar and viscoelastic characteristics of hydrogels. And the in vitro alcohol-induced ALD model was also proved to be successfully established, even presenting equal results with ALD mice. Furthermore, epigallocatechin gallate (EGCG) as an intervention on ALD was confirmed in both in vitro and in vivo model. The findings indicate our simple artificial liver model is not only highly predictive but also easy to apply to drug screening and implantation studies, suggesting a promising alternative to animal models. Moreover, as the main active ingredient of tea, EGCG's effective intervention and reversal effect on fatty liver provides support for the theory that green tea could prevent alcoholic fatty liver.

Utilizing solar steam generation to treat seawater and sewage, as an emerging and effective technology, can obtain clean water. There is an abundance of water demand and a shortage of water supply in the world today. Herein, we demonstrate an integrated evaporator of boron nanosheets modified with molybdenum disulfide (MoS2) as a photothermal materials and a konjac glucomannan (KGM) sponge with excellent pore structure as a thermal insulator and water supplier for solar clean water generation. A rapid evaporation rate (1.538 kg m−2 h-1) and high solar evaporation efficiency (96.5 %) under 1-sun radiation (1 kW m−2) can be achieved in the two-dimensional structure system. This work provides a new way to design and manufacture renewable solar steam generation for water purification.

The authors are presenting an electrochemical aptasensor for tumor necrosis factor-alpha (TNF-α) detection that is aided by the use of magnetic nanoparticles (NPs) and two DNA probes. Firstly, magnetic NPs coated with gold NPs (Fe3O4@AuNP) are synthesized. Then, DNA probe 1 with a terminal thiol group is immobilized on the surface of Fe3O4@AuNP via gold-thiol chemistry. DNA probe 1 is then hybridized with DNA probe 2, which is labeled with Methylene Blue (MB). The composite of Fe3O4@AuNP-DNA duplex is formed as a result, which can be easily absorbed on a magnetized glassy carbon electrode. The electrochemical signal is obtained after reductant-mediated amplification. Since MB-labeled DNA probe 2 is the aptamer against TNF-α, it will be released in the presence of TNF-α. This process leaves Fe3O4@AuNP-DNA probe 1 on the surface of the electrode. Thus, the recorded electrochemical response decreases dramatically. The assay, best operated at a working voltage of −0.39 V (vs. SCE), has a linear response in the 10 pg mL−1 to 100 ng·mL−1 TNF-α concentration range, and the limit of detection is 10 pg mL−1. The sensing strategy is highly sensitive and selective, and has been successfully applied to real samples.

A novel electrochemical aptasensor for the detection of trace protein is proposed based on proximity binding-induced strand displacement and hybridization chain reaction. This method is proven to be highly selective and has potential practical utility, and offers new opportunities for the convenient detection of proteins with an enzyme-free amplification process.

Background Lung cancer remains the most common cause of cancer-related deaths, with a high incidence and mortality in both sexes worldwide. Chemoprevention has been the most effective strategy for lung cancer prevention. Thus, exploring novel and effective candidate agents with low toxicity for chemoprevention is essential and urgent. Houttuynia cordata Thunb. (Saururaceae) (H. cordata), which is a widely used herbal medicine and is also popularly consumed as a healthy vegetable, exhibits anti-inflammatory, antioxidant and antitumor activity. However, the chemopreventive effect of H. cordata against benzo(a)pyrene (B[a]P)-initiated lung tumorigenesis and the underlying mechanism remain unclear. Methods A B[a]P-stimulated lung adenocarcinoma animal model in A/J mice in vivo and a normal lung cell model (BEAS.2B) in vitro were established to investigate the chemopreventive effects of H. cordata and its bioactive compound 2-undecanone against lung tumorigenesis and to clarify the underlying mechanisms. Results H. cordata and 2-undecanone significantly suppressed B[a]P-induced lung tumorigenesis without causing obvious systemic toxicity in mice in vivo. Moreover, H. cordata and 2-undecanone effectively decreased B[a]P-induced intracellular reactive oxygen species (ROS) overproduction and further notably protected BEAS.2B cells from B[a]P-induced DNA damage and inflammation by significantly inhibiting phosphorylated H2A.X overexpression and interleukin-1β secretion. In addition, H. cordata and 2-undecanone markedly activated the Nrf2 pathway to induce the expression of the antioxidative enzymes heme oxygenase-1 (HO-1) and NAD(P)H: quinone oxidoreductase 1 (NQO-1). Nrf2 silencing by transfection with Nrf2 siRNA markedly decreased the expression of HO-1 and NQO-1 to diminish the reductions in B[a]P-induced ROS overproduction, DNA damage and inflammation mediated by H. cordata and 2-undecanone. Conclusions H. cordata and 2-undecanone could effectively activate the Nrf2-HO-1/NQO-1 signaling pathway to counteract intracellular ROS generation, thereby attenuating DNA damage and inflammation induced by B[a]P stimulation and playing a role in the chemoprevention of B[a]P-induced lung tumorigenesis. These findings provide new insight into the pharmacological action of H. cordata and indicate that H. cordata is a novel candidate agent for the chemoprevention of lung cancer. Electronic supplementary material The online version of this article (10.1186/s13046-019-1255-3) contains supplementary material, which is available to authorized users.

A simple approach has been designed for the synthesis of nitrogen-containing carbogenic polymer dots (NPDs) with relatively high nitrogen concentration (10.5 at.%), tunable size distribution, high yield (25%), and a high degree of graphitization, through a microwave-assisted polymerization of polybromopyrroles in an alkaline ethanolthermal environment at 80 °C. The structure, composition, morphology, and optical properties of NPDs were characterized with X-ray diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, ζ-potential, transmission electron microscopy, scanning probe microscopy, UV–vis absorbance, and photoluminescence techniques. At excitation wavelengths ( λ e x ) before and after 360 nm, NPDs exhibit a dual emission behavior in terms of λ e x -independence and λ e x -dependence, respectively. The absolute quantum yield of NPDs is greatly improved to be 24% from 3% after simple surface reduction by NaBH 4 . The fluorescence quenching mechanism of NPDs has been carefully investigated by using twenty aromatic compounds as quenchers. Through theoretical calculations and instrumental analysis, we conclude that non-photochemical quenching rather than the fluorescence resonance energy transfer and charge transfer dominates the quenching of NPDs by aromatic compounds. This insight shows the way for selective fluorescent detection of trace aromatic compounds with carbogenic dot-based sensors.

Both gingerol and capsaicin are agonists of TRPV1, which can negatively control tumor progression. This study observed the long-term effects of oral administration of 6-gingerol alone or in combination with capsaicin for 20 weeks in a urethane-induced lung carcinogenic model. We showed that lung carcinoma incidence and multiplicity were 70% and 21.2 ± 3.6, respectively, in the control versus 100% and 35.6 ± 5.2 in the capsaicin group (P < 0.01) and 50% and 10.8 ± 3.1 in the 6-gingerol group (P < 0.01). The combination of 6-gingerol and capsaicin reversed the cancer-promoting effect of capsaicin (carcinoma incidence of 100% versus 20% and multiplicity of 35.6 ± 5.2 versus 4.7 ± 2.3; P < 0.001). The cancer-promoting effect of capsaicin was due to increased epidermal growth-factor receptor (EGFR) level by decreased transient receptor potential vanilloid type-1 (TRPV1) level (P < 0.01) . The capsaicin-decreased EGFR level subsequently reduced levels of nuclear factor-κB (NF-κB) and cyclin D1 that favored enhanced lung epithelial proliferation and epithelial-mesenchymal transition (EMT) during lung carcinogenesis (P < 0.01). In contrast, 6-gingerol promoted TRPV1 level and drastically decreased the levels of EGFR, NF-κB, and cyclin D1 that favored reduced lung epithelial proliferation and EMT (P < 0.01). This study provides valuable information for the long-term consumption of chili-pepper-rich diets to decrease the risk of cancer development.

As one of the most anticipated energy storage systems, the application of lithium-sulfur batteries is hindered by low conductivity of insoluble sulfur species (S8, Li2S2 and Li2S), the shuttle effect of soluble lithium polysulfides (Li2Sx, 4 = x ≤ 8) and the volume expansion of sulfur species during the cycling. To overcome these barriers, a tunable geometry of flower-like FeMoO4/FeS2/Mo2S3 composite is successfully investigated using simple one-step solvothermal technique. Fe-based sulfides with good conductivity and Mo-based sulfides with the efficient ability of catalytic sulfur species conversion are promising sulfur host for high performance lithium-sulfur batteries (LSBs). It should be noted that this is first time to introduce FeMoO4 as polysulfides anchoring material into the lithium-sulfur system. Consequently, the flower-like composite with 79 wt % sulfur loading exhibits a high initial capacity of 1600 mA h g−1 and a reversible capacity of 781 mAh g−1 after 300 cycles at 1 C. Even at a high rate of 10 C, a capacity of 421 mAh g−1 is maintained after 300 cycles.

Solar-powered vapor generation, by a strict structural design, has become one of the most effective ways to utilize solar energy for water remediation. Recently, low-cost molybdenum disulfide (MoS2) based solar evaporation systems have provided an ideal way for solar-powered vapor generation, while instability and low evaporation rate still remain as challenges. In this work, we introduce a stabilized Mo2S3 by FeS2 (Fe-Mo2S3) based porous solar evaporation system as a light-harvesting and light-thermal conversion material. The system reveals a dual feature with high light absorption and water supply, leading to a higher evaporation rate up to ~2.4 kg m-2 h-1 than MoS2 under 1 kW m-2 solar illumination. Long-time photothermal and cycle tests for brine further reveals that the porous solar evaporation system has excellent photothermal stability and relieves salt blockage problem to some extent. Meanwhile, this system can directly be used for the purification of seawater, organic solution and heavy metal ion solution. The water purification rate can reach approximately 1.76 kg m−2 h−1 under natural sun-light. It provides a very promising material for water purification, water pollution remediation and other related photothermal technologies.

Multiple-color-emissive carbon dots (CDs) is one of the hotspots due to its potential in multi-fields. However, the exploring of efficient synthetic strategies and emission mechanisms still remain challenging. Herein, we report a facile solvothermal route to prepare CDs with tunable photoluminescence (PL) from green to red via a novel PL-tuning strategy of sulfur doping and water engineering. By detailed characterizations and comparison, it is demonstrated that the S doping can significantly increase the content of graphitic nitrogen, resulting in the fluorescence shifting from green to yellow; on the other hand, water engineering is able to yield carboxyl group and enhance surface oxidation degree, which can further facilitate the PL shifting from yellow to red. Owning to multicolor emissions and S doping, the prepared PL-tunable CDs present versatility in various applications including fluorescent films, light-emitting diodes (LED), bioimaging probe and highly sensitive Fe3+ detector.

Nonprecious cocatalyst decoration is of great importance to create more active sites on the photocatalyst surface and provides insights into the photocatalytic activity enhancement. Herein, through facile hydrothermal and precipitation routes, the surface of MgAl layered double hydroxide (LDH) was modified by ultrafine NiS nanoparticles as a cocatalyst to design MgAl-LDH/NiS hybrid photocatalysts for highly-efficient photocatalytic hydrogen generation. The presence of NiS not only enhances the visible-light absorption but also promotes the separation and transfer of photogenerated charges, thereby boosting the photocatalytic activity of MgAl-LDH/NiS (35.8 μmol h−1) compared with bare MgAl-LDH (2.7 μmol h−1). The MgAl-LDH/NiS hybrid, moreover, displays a superior stability towards photocatalytic hydrogen evolution. This research offers a facile route to develop a high-performance photocatalyst using low-cost metal sulfide as cocatalyst for visible light photocatalytic hydrogen production.

Solar steam generation and photocatalytic degradation have been regarded as the most promising techniques to address clean water scarcity issues. Although enormous efforts have been devoted to exploring high-efficiency clean water generation, many challenges still remain in terms of single decontamination function, relatively low efficiency, and inability to practical application. Herein, we first report the bioinspired fabrication of black titania (BT) nanocomposites with moth-eye-like nanostructures on carbon cloth for solar-driven clean water generation through solar steam generation and photocatalytic degradation. The moth-eye-like BT nanoarrays can largely prolong the effective propagation path of absorbing light and enhance the scattering of light, thereby exhibiting outstanding light absorption of 96% in the full spectrum. Such hierarchical-nanostructured BT nanocomposites not only impressively achieve solar steam efficiency of 94% under a simulated light of 1 kW m–2 but also show the prominent per...

Endophilin A1 is a member of the N-BAR domain-containing endophilin A protein family that is involved in membrane dynamics and trafficking. At the presynaptic terminal, endophilin As participate in synaptic vesicle recycling and autophagosome formation. By gene knockout studies, here we report that postsynaptic endophilin A1 functions in synaptic plasticity. Ablation of endophilin A1 in the hippocampal CA1 region of mature mouse brain impairs long-term spatial and contextual fear memory. Its loss in CA1 neurons postsynaptic of the Schaffer collateral pathway causes impairment in their AMPA-type glutamate receptor-mediated synaptic transmission and long-term potentiation. In KO neurons, defects in the structural and functional plasticity of dendritic spines can be rescued by overexpression of endophilin A1 but not A2 or A3. Further, endophilin A1 promotes actin polymerization in dendritic spines during synaptic potentiation. These findings reveal a physiological role of endophilin A1 distinct from that of other endophilin As at the postsynaptic site.

The authors are presenting a rapid method for the determination of theophylline using unique non-crosslinking gold nanoparticle (AuNP) aggregation. An RNA aptamer against theophylline is firstly split into two RNA fragments which then interact with bare AuNPs. The two RNA probes cause an enhancement of the salt tolerance of AuNPs. However, in the presence of theophylline, the RNA probes form a complex with theophylline so that less RNA probes are available to protect the AuNPs from salt-induced aggregation. Theophylline induced aggregation of AuNPs is accompanied by a color change from red to blue. The color change can be detected visually and via UV-vis absorptiometry by ratioing the absorbances at 650 and 520 nm. The ratio increases linearly in the 0.1 to 20 μM theophylline concentration range, with a 67 nM limit of detection. The method is highly sensitive and selective. Graphical abstract Single-stranded split RNA aptamers (R1 and R2) protect gold nanoparticles (AuNPs) from salt-induced non-crosslinking aggregation. After recognition of theophylline by the RNA probe, the unprotected AuNPs aggregate and undergo a color change from red to blue, and this is used to quantify the theophylline concentration.

An integrated structure has been designed by grafting the polymer of polybromopyrroles (PPBP) onto reduced graphene oxide (RGO) to produce RGO/PPBP nanocomposites with superior electrochemical performance for supercapacitors. The RGO/PPBP nanocomposites are featured with a high nitrogen content (>9 at%), enhanced degree of graphitization, improved specific surface area, abundant micropores, and a tunable hierarchical structure on the basis of sample characterization by XRD, Raman, FT-IR, XPS, SEM, high-resolution TEM, BET, and scanning probe microscopy (SPM) techniques. The grafting of PPBP onto RGO not only suppresses agglomeration and restacking of RGO but also tailors the growth of PPBP on RGO, producing a developed hierarchical structure beneficial for mass/charge transfer. The synergistic effect between RGO and PPBP ensures superior electrochemical performance of RGO/PPBP. In a three-electrode mode, the typical RGO/PPBP electrode presents a galvanostatic capacitance (Cg) of 256 F g−1 at a current density of 10 A g−1, with a capacitance retention of 99.2% after 10 000 cycles in 1 mol L−1 H2SO4. More significantly, the typical RGO/PPBP‖RGO/PPBP supercapacitor cell exhibits a high Ccell value of 68 F g−1 at 5 A g−1, with a capacitance retention of 91.9% after 10 000 cycles. Also, relatively high energy density values of 13.6, 9.4, and 6.7 W h kg−1 with the corresponding power density of 0.5, 2.5, and 10 kW kg−1 are achieved, enabling the tested cell to stay at the high level for carbon-based supercapacitors with an aqueous electrolyte.

To investigate the effects of perinatal fluoride exposure on learning and memory ability of mouse offspring, ICR female mice were received different doses of sodium fluoride (0, 25, 50, 100 mg/L NaF) from pregnant day 7 to lactational day 21. Pups were exposed to fluoride through the cord blood and breast milk. Open field test showed that compared to the control group, perinatal fluoride exposure significantly decreased the number of entries into the center zone in 100 mg/L NaF group. In the eight-arm maze test, the number of working memory errors, reference memory errors, and the total arm entries were significantly increased in fluoride treatment groups, compared to the control group. Additionally, 100 mg/L NaF significantly elevated the expression levels of miR-124, miR-132, and DiGeorge syndrome chromosomal region 8 (DGCR8) in hippocampus of mouse pups at postnatal day (PND) 21. Contrarily, methyl CpG binding protein 2 (MeCP2) were dramatically reduced in 50 and 100 mg/L NaF groups, while cAMP-response element binding protein (CREB) mRNA level was significantly decreased in all fluoride groups. These findings suggested that the impairment of learning and memory in mouse offspring induced by perinatal fluoride exposure may partly result from the enhanced miR-124 and miR-132 and the alterations of their target genes.

The overuse of antibiotics which exerts the selective pressure for bacterial pathogens has facilitated the spread of antibiotics' resistance. Metallo-β-lactamases (MβLs) are zinc enzymes produced by an increasing number of bacterial pathogens. They can readily cleave carbapenems and most other β-lactams that are mainstays of therapy for bacterial infections. MβL-conferred resistance to antibiotics is most worrisome due to MβLs exhibiting very broad-spectrum resistance. Therefore, the bacteria carrying MβLs have recently become a significant clinical threat. No clinically useful MβLs inhibitor has been discovered yet. To address the serious threat to public health posed by the MβL-conferred resistance to antibiotics, novel effective MβL inhibitors are urgently needed. This review mainly describes various MβL inhibitors, giving special attention to their antibacterial activity, mechanisms of action, structure-activity relationships and synergetic effect with clinically available antibiotics.

A fluorescence “turn-off” and color “turn-on” probe for late IB metal ions (Fe3+/Co2+/Ni2+/Cu2+/Zn2+) was developed based on rhodamine B. The probe was synthesized by condensation between rhodamine B and 8-hydroxyjulolidine-9-carboxaldehyde, which provided excellent selectivity function for late IB metal ions detection. It binds Cu2+ in a 1:1 stoichiometry in acetonitrile solution. This probe displays distinct color and fluorescence change upon the addition of late IB metal ions and little interference with other biologically relevant metal ions. Limit of detection for Cu2+, Fe3+, and Co2+ is higher than that of Zn2+ and Ni2+. In addition, the limit of detection toward Cu2+ is about 312 times lower than the World Health Organization (WHO) recommended level in drinking water.

MicroRNAs (miRNAs) are a class of small non-coding RNAs that are closely associated with carcinogenesis. Accumulating data indicate that miR-196b participates in the development of various types of cancers. However, the role of miR-196b in the formation of hydatidiform mole (HM) is still unclear. Our previous studies have demonstrated that miR-196b levels were decreased in JAR and BeWo cells and in HM tissue samples, as demonstrated by RT-PCR analysis. Furthermore, we discovered that overexpression of miR-196b in JAR and BeWo cells inhibited cellular proliferation, migration and invasion, as shown by Cell counting kit-8 (CCK-8) and transwell assays, respectively. Subsequently, we explored the interaction of miR-196b with its target gene in human choriocarcinoma cell lines. MAP3K1 is a target gene predicted by bioinformatic analysis that was previously shown to exhibit reduced expression levels following treatment with miR-196b in JAR and BeWo cells. We demonstrated that MAP3K1 was a direct target of miR-196b using the dual-luciferase reporter assay in Hela cells. In summary, the present study demonstrated that miR-196b suppressed proliferation, migration and invasion of human choriocarcinoma cells by inhibiting its transcriptional target MAP3K1. miR-196b and MAP3K1 may be considered potential targets for the clinical treatment of HM.

Increasing evidence shows that exposure to an enriched environment (EE) after cerebral ischemia/reperfusion injury is neuroprotective in animal models. However, little is known about of the neuroprotective effects of EE exposure prior to injury. The current study examined the effects of prior EE exposure on inducible and neuronal nitric oxide syntheses (iNOS and nNOS) after transient middle cerebral artery occlusion (tMCAO) in rats. A total of 72 rats were exposed to EE or standard housing condition (SC) for 1 month, followed by 90-min MCAO and reperfusion or sham surgery, leading to the following three groups: (1) EE+MCAO (n=24), (2) SC+MCAO (n=24), (3) SC+sham (n=24). Rats were sacrificed at 1, 6, or 24h after MCAO (n=6/group) for iNOS and nNOS mRNA quantification by real-time PCR and at 24h after MCAO (n=6/group) for iNOS and nNOS protein quantification by Western blot or were evaluated for neurological function outcomes, then sacrificed to assess infarct volume (n=6/group). Results showed that prior exposure to EE reduced iNOS and nNOS mRNA and protein and improved neurological status after MCAO without affecting infarct volume, suggesting that EE may provide neuroprotection via ischemic preconditioning.