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At the organelle level, pathogenesis due to abnormal concentrations of cysteine (Cys) is of great significance for the early diagnosis and treatment of related diseases. Generally speaking, organelle localization requires the participation of specific target groups, which increases the difficulty of synthesis. Herein, through simple synthesis, a novel biflavone derivative (BFD) that exhibits excited-state intramolecular proton transfer (ESIPT) was obtained and successfully located in mitochondria without target groups. The probe BFD can distinguish Cys from Hcy and GSH with a rapid response (< 5 s) and showed visual detection for Cys with a large Stokes shift (about 260 nm). Because of its nanomorphology in solution and surface functional groups, the probe BFD can enter the cell smoothly and achieve mitochondrial localization. Owing to its excellent optical performance, the probe BFD was successfully applied to the imaging of endogenous Cys in HeLa cells and zebrafish.

Deep eutectic solvents (DESs) are a new class of green solvents with potential applications for the extraction of target compounds from both liquid and solid samples. However, current research in t...

In order to obtain a material with excellent microwave absorption performance, polyvinyl alcohol (PVA) sponge was employed as the template. The porous structure of the sponge can facilitate faster and more uniform diffusion of the ferric nitrate liquid during the dipping and obtain a uniform distribution of the ferromagnetic particles, which serves as a functional phase to enhance the microwave absorption properties. The Fe@Fe3O4-C nanocomposite can then be fabricated through a dipping/carbonization process. The special core–shell structure effectively improves the dielectric and magnetic loss and provides proper impedance matching. The results indicate that the prepared samples show excellent microwave absorption performance, with maximum effective absorption bandwidth up to 7.9 GHz at a thickness of 2.27 mm. The maximum reflection loss can reach −48.36 dB at 9.6 GHz. Therefore, it is feasible to use PVA sponge as a template to fabricate porous Fe@Fe3O4-C nanocomposite with excellent microwave absorption performance.

The TNF-related apoptosis-inducing ligand (TRAIL) triggers apoptosis in cells by signaling through the O-glycosylated death receptors (DR4 and DR5), but the sensitivity to TRAIL-induced apoptosis of cells varies, and the attributes of this phenomenon are complex. Human carcinoma cells often express truncated O-glycans, Tn (GalNAcα1-Ser/Thr), and Sialyl-Tn (Siaα2-6GalNAcα1-Ser/Thr, STn) on their surface glycoproteins, yet molecular mechanisms in terms of advantages for tumor cells to have these truncated O-glycans remain elusive. Normal extended O-glycan biosynthesis is regulated by a specific molecular chaperone Cosmc through assisting of the correct folding of Core 1 β3 Galactosyltransferase (T-synthase). Here, we use tumor cell lines harboring mutations in Cosmc, and therefore expressing Tn and STn antigens to study the role of O-glycans in TRAIL-induced apoptosis. Expression of Tn and STn in tumor cells attenuates their sensitivity to TRAIL treatment; when transfected with wild-type Cosmc, these tumor cells thus express normal extended O-glycans and become more sensitive to TRAIL treatment. Mechanistically, Tn/STn antigens impair homo-oligomerization and stability of DR4 and DR5. These results represent the first mechanistic insight into how O-glycan structures on cell surface modulate their sensitivity to apoptotic stimuli, suggesting expression of Tn/STn may offer tumor cell survival advantages through altering DR4 and/or DR5 activity.

Hypochloric acid (HOCl) plays vital roles in cell signaling and homeostasis which involved in many related diseases. Therefore, the accurate detected level of OCl− for discussing the complex contributions of OCl− to human health is of great significance. In this study, a novel mitochondrion-targeting fluorescent probe DMI bearing a carbon-carbon double bond as an OCl−-responsive site has been developed. Probe DMI exhibited specific fluorescence response toward OCl− with fast response (within 4 s) and high sensitivity (detection limit is 0.05 μM), where the obvious color changes could be observed by the naked eye. More importantly, DMI could be applied in the bioimaging of OCl− in living A549 cells successfully benefited from its good sensing properties and low toxicity. Fluorescence co-localization test was further carried out and confirmed mitochondria-targetable ability of DMI which can be used for investigating physiological function of HOCl at organelle levels.

Negative permittivity has taken off as a research topic in percolative composites recent years. Comparing with the common conductive constituent element in the preparation of metamaterials such as metal, one-dimensional conductive carbon nanotubes (CNTs) provide another choice of functional phase. In this paper, barium titanate (BaTiO3) with multi-walled carbon nanotubes (MWCNTs) uniformly dispersed in the ceramic matrix were prepared by traditional ceramic sintering technology. Field emission scanning electron microscopy, X-ray diffraction and Raman spectroscopy were used to characterize microstructures and phase composition of the metacomposites. With the increasing of CNTs content, the percolation phenomenon of electrical conductivity (9.95 wt%) was found and the conductive mechanism changed because of the formation of conductive MWCNTs networks. Moreover, the negative permittivity behavior was observed when the MWCNTs content reached 7 wt% and the plasma-like negative permittivity behavior could be well explained by the low frequency plasmonic state generated from conductive nanotube networks using the Drude model.

Surface modification has been proven to be an effective approach for ion exchange membranes to achieve separation of counterions with different valences by altering interfacial construction of memb...

The preparation of quaternary ammonium polysulfone anion exchange membranes (AEMs) with good dimensional stability and alkaline stability is an urgent problem to solve. In response, a series of cross-linked based on polysulfone and 4, 4′-trimethylenedipiperidine (TMDP) as crosslinkers with different degrees AEMs were developed in this work through a simple process. Among the fabricated AEMs, CAPSF-5 exhibits superb alkaline stability in a 1 M KOH aqueous solution at 60 °C for 15 days, whereas the non-crosslinked APSF membrane became tremendously brittle within 24 h and could not be further studied under the same conditions. In addition, even at 60 °C, CAPSF-5 demonstrates a superior dimensional stability compared to the non-crosslinked APSF membrane due to the formation of a dense internal network structure. These observations demonstrate that crosslinked CAPSF membranes can be a viable strategy to improve the deficiency of the polysulfone backbone, especially in terms of alkaline stability.

Although cyanogen ion (CN-) plays important role in industry which also bring acute environmental pollution. More serious, trace CN- enters the human body can cause serious consequences and even death. Therefore, it is of great significance to detect trace CN- with high sensitivity. Herein, a novel aggregation-induced emission (AIE) probe C-BH was synthesized based on coumarin matrix. Probe C-BH showed high selectivity and sensitivity toward CN- by dual channel response due to the excited state intramolecular proton transfer (ESIPT). The low detection limit was calculated to be 0.05 µM. Moreover, probe C-BH was successfully used for imaging CN- in living cells and zebrafish due to its low toxicity and excellent optical properties.

Hypochlorite is an important active oxygen species formed in living organisms, and rapid and highly sensitive detection of trace hypochlorite is of great significance for understanding the mechanism of diseases caused by abnormal hypochlorite concentrations at an early stage. Although aggregation-induced emission (AIE) probes are highly important for analyte de-tection in living organisms, there is a lack of AIE probes for hypochlorite detection. In this study, two AIE probes based on benzothiazole derivatives (BTD-1 and BTD-2) were designed and synthesized. Both probes exhibited good AIE charac-teristics and allowed different visual detection for hypochlorite. Additionally, the two probes could be used to detect endogenous hypochlorite in mitochondria and were successfully applied for in vivo hypochlorite imaging in zebrafish.

Tn antigen is a truncated O‐glycan, frequently detected in colorectal cancer (CRC), but its precise role in CRC metastasis is not well addressed. Here we investigated the effects of Core 1 β3Gal‐T specific molecular chaperone (Cosmc) deletion‐mediated Tn antigen exposure on CRC metastasis and its underlying mechanism. We first used CRISPR/Cas9 technology to knockout Cosmc, which is required for normal O‐glycosylation, and thereby obtained Tn‐positive CRC cells. We then investigated the biological consequences of Tn antigen expression in CRC. The results showed that Tn‐positive cells exhibited an enhanced metastatic capability both in vitro and in vivo. A further analysis indicated that Tn antigen expression induced typical activation of epithelial‐mesenchymal transition (EMT). Mechanistically, we found that H‐Ras, which is known to drive EMT, was markedly up‐regulated in Tn‐positive cells, whereas knockdown of H‐Ras suppressed Tn antigen induced activation of EMT. Furthermore, we confirmed that LS174T cells (Tn‐positive) transfected with wild‐type Cosmc, thus expressing no Tn antigen, had down‐regulation of H‐Ras expression and subsequent inhibition of EMT process. In addition, analysis of 438 samples in TCGA cohort demonstrated that Cosmc expression was reversely correlated with H‐Ras, underscoring the significance of Tn antigen‐H‐Ras signalling in CRC patients. These data demonstrated that Cosmc deletion‐mediated Tn antigen exposure promotes CRC metastasis, which is possibly mediated by H‐Ras‐induced EMT activation.

Hypochlorite plays a critical role in various physiological processes and is involved in many diseases. Thus, real-time, rapid, and accurate monitoring of hypochlorite has important medical and physiological significance. Herein, a novel coumarin-pyridine derivative (CPD) probe was designed and synthesized, which exhibited fantastic advantages, such as a rapid response (within 10 s), naked eye recognition, large Stokes shift (185 nm), dual-channel detection, and high selectivity and sensitivity toward OCl- (detection limit 0.012 μM, S/N = 3). Furthermore, the current CPD probe was successfully used to image OCl- in the mitochondria of both A549 cells and zebrafish, which further demonstrated its suitability for practical applications in biological systems.

Novel anion exchange membranes with enhanced ion exchange capacity, dimensional stability and alkali stability were prepared by a facile synthesis method. Internal crosslinking networks in the resulting membranes were achieved by reacting chloromethylated polysulfone with 4,4′-trimethylene bis(1-methylpiperidine) (BMP), where BMP was used as both a quaternization reagent and crosslinker without requirement of post-functionalization. In order to evaluate the alkali resistance and dimension stability performance of the resulting membranes, the molar ratio of BMP in the resulting membranes was fixed at four different contents: 40%, 60%, 80% and 100%. The obtained membranes were accordingly denoted as CAPSF-N, in which N = 40, 60, 80 and 100, respectively. Due to the dense internal network structure and spatial conformation of the six-membered rings, the resulting CAPSF-N AEMs showed enhanced dimensional structures (at 60 °C, the water uptakes and swelling ratios of CAPSF-N were 8.42% to 14.84% and 2.32% to 5.93%, respectively, whereas those for the commercial AEM Neosepta AMX were 44.23% and 4.22%, respectively). In addition, after soaking in 1 M KOH solution at 60 °C for 15 days, the modified membranes exhibited excellent alkaline stability. The CAPSF-100 membrane showed the highest alkali stability (retained 85% of its original ion exchange capacity and 84% of its original OH− conduction after the alkaline stability test), whereas the non-crosslinked APSF broke into pieces. Additionally, compared to the commercial Neosepta AMX membrane under the same test conditions, the desalination efficiency of CAPSF-100 was enhanced, and the energy consumption was lower.

A coumarin-diaminomaleonitrile derivative (C-DAN) was designed and prepared. Upon addition of hypochlorite (OCl-), the fluorescence emission peak of C-DAN at 475 nm was gradually enhanced with a rapid response (within 5 s); meanwhile, the color of the solution changed from dark red to bright yellow which can be observed with the naked eye. Furthermore, owing to its advantages including high selectivity, sensitivity, and low toxicity, our C-DAN probe has been applied for detecting OCl- in living cells and zebrafish, indicating it is an ideal tool for biological applications.

Hypochlorite (OCl−) plays important roles both in physiological and pathological processes, the detection of which is of great significance. Herein, a novel fluorescent probe based on the triphenylamine-type schiff base derivative (TPAD) was developed to detect OCl−. Probe TPAD exhibited specific fluorescence response toward ClO− with the fluorescence quenching rate up to 80%, and the detection limit was estimated to be 0.8 μM. The sensing mechanism study demonstrated that TPAD reacted with ClO− via an oxidation process, which was evidenced by MS and NMR characterization. Moreover, owing to the excellent sensing properties and negligible cytotoxicity, TPAD was successfully applied in the bioimaging of OCl− in living A549 cells.

In this work, we have investigated a series of anion exchange membranes (AEMs) based on brominated poly(2,6-dimethyl-1,6-phenylene oxide) (BPPO) tethered with three saturated heterocyclic quaternary ammonium groups (QAs) of 1-methylpyrrolidine (MPY), N-methylpiperidine (MPRD), and 4-methylmorpholine (MMPH) for electrodialysis (ED) applications, respectively, along with BPPO with trimethylamine (TMA) and Neosepta AMX made for comparison. Our investigations demonstrate that the optimized BPPO-MPRD, having an ion exchange capacity of 1.67 mmol g−1, is highly stable in aqueous KOH (1 mol L−1) with ion exchange capacity retention ratio of 85.1% and hydroxide conductivity retention ratio of 80.3% at 60 °C for over 15 days, relative to other heterocyclic amine decorated AEMs. In ED application process, BPPO-MPRD shows the NaCl removel ratio of 98.8% and energy consumption of 12.58 kWh kg−1, outperforming the Neosepta AMX (97.4% & 15.76 kWh kg−1). The results demonstrate that the as-prepared BPPO-MPRD AEM can be applied in ED.

A novel red-emitting fluorescent probe (DDNA) for cysteine has been rationally designed and synthesized, which exhibited a low limit of detection to Cys (0.26 μM) as well as a favorable large stokes shift (λEm-λEx = 128 nm). This novel fluorophore (HDM), which features a large π-conjugation system and typical intramolecular charge transfer (ICT) process, has a long emission wavelength at 631 nm. Besides that, as a turn-on fluorescent probe, it shows high selectivity and sensitivity for Cys over other metal ions and amino acids including the similar structured homocysteine (Hcy) and glutathione (GSH). Finally, the probe DDNA was successfully applied to bioimage intracellular Cys in Hela cells with low cytotoxicity.

Highly sensitive and selective detection for hypochlorite anion (OCl−) is of extreme significance due to its important role and function in biological systems. Herein, a diaminomaleonitrile derivative (DMD) has been developed as a novel ratiometric and colorimetric fluorescent probe for OCl− detection. Consistent with the UV–vis spectral change, the probe DMD exhibited promptly a color change from canary yellow to gules upon the addition of OCl−, which could be easily observed by naked-eyes. In addition, the detection limit was found to be 0.5 nM, which is much lower than that of many reported OCl− probes. More importantly, owing to its excellent sensing properties and negligible cytotoxicity, probe DMD can be conveniently applied to image intracellular OCl− in living cells, indicating it a promising tool in biological applications.

A novel AIEE (aggregation-induced emission enhancement)-active conjugated polymer incorporating thiazole and tetraphenylethene (TPE) was designed and synthesized via Pd-catalyzed Sonogashira coupling reaction. The polymer shows typical AIEE phenomena, and emits green fluorescence in the mixed solvent of tetrahydrofuran (THF) and water, reaching a maximum fluorescence intensity when the fraction of water is 90%. In the aqueous phase (fw = 90%), the polymer sensor exhibits “turn-off” fluorescence quenching responses towards Hg2+ and Ag+ over other cations, such as Li+, K+, Ca2+, Mg2+, Ba2+, Zn2+, Cd2+, Co2+, Ni2+, Pb2+, Cu2+, Al3+ and Fe3+. The obvious fluorescence change (bright yellow to weak emission) can be clearly observed by the naked eyes.

We described herein a new AIE-active polymer sensor incorporating triazole moiety for Hg2+ detection in aqueous solution. The polymer sensor P1 was synthesized from tetraphenylethene and diazidobenzene via click reaction. It shows typical AIE feature, and emits cyan fluorescence in the mixture of tetrahydrofuran and water, reaching the strongest fluorescence when the fraction of water (fw) is 90%. In aqueous solution (fw = 90%), the polymer sensor can exhibit fluorescence quenching response towards Hg2+ over other competing metal ions, with the fluorescence color changed from cyan to almost no emission, which can be clearly observed by the naked eyes under 365 nm UV lamp.

A novel simple and readily synthesized turn-on fluorescent probe 4-(benzo[d]thiazol-2-yl)-1,3-phenylene bis(2-chloroacetate) (BPBC) for cysteine (Cys) was reported. This probe was designed based on an excited-state intramolecular proton transfer (ESIPT) dye: benzothiazole, and two chloroacetate groups present in benzothiazole as the reaction sites for Cys. It shows high selectivity and sensitivity for Cys over other amino acids including the similar structured homocysteine (Hcy) and glutathione (GSH). In addition, probe BPBC was successfully applied to bioimage intracellular Cys in living cells with low cytotoxicity. More importantly, a paper test strip system was developed with probe BPBC for Cys detection conveniently.

A novel turn-on fluorescent probe (DDND) for highly selective detection of biothiols over other amino acids was synthesized and investigated in this work, which used the 2,4-dinitrobenzenesulfonyl (DNBS) group as a fluorescent quencher. The novel fluorophore (HDM) features a large π-conjugation system and a typical intramolecular charge transfer (ICT) process and has a long emission wavelength at 623 nm as well as a large Stokes shift (λem − λex = 131 nm). Besides that, this red-emitting probe exhibited good linearity ranges with a low detection limit of 0.23 μM for Cys, 0.34 μM for Hcy and 0.41 μM for GSH respectively. Upon titration of thiols, the color of the solution changed from yellow to dark red, which means it can be detected by naked eyes. Finally, probe DDND was successfully applied to bioimage intracellular Cys in HeLa cells with low cytotoxicity.

An efficient naphthalene-based fluorescent probe (BTNA) for cysteine (Cys) has been rationally designed and synthesized in this work, which consists of a 6-(2-benzothiazolyl)-2-naphthalenol (BNO) fluorophore connected with an acrylate group (the fluorescence quenching and response group). This probe was designed based on a photo induced electron transfer (PET) process and the conjugated addition/cyclization sequence mechanism was employed for Cys detection. It is notable that this novel probe exhibits good linearity ranges with a low detection limit of 0.18 μM for Cys as well as a large stokes shift (λem − λex = 140 nm). Besides these, as a turn-on fluorescent probe, it shows high selectivity and sensitivity for Cys over other amino acids and common ions including the similar structured homocysteine (Hcy) and glutathione (GSH). Finally, the probe BTNA was successfully applied for bioimaging intracellular Cys in living Hela cells with low cytotoxicity.

Monitoring trace hypochlorite at the organelle level is important for the early diagnosis of diseases caused by abnormal hypochlorite levels. Traditional organelle localization probes require the introduction of specific target groups, which increases the requirements for the molecular structure and complicates the synthesis. Developing non-targeted fluorescent probe for organelle level detection is of great significance. In this study, a novel coumarin-based aggregation-induced emission probe (AIE-CDs) was designed and prepared for OCl− determination with fast response (within 5s) and high sensitivity (detection limit is 0.32 μM). In aqueous solution, probe AIE-CDs emerged as spherical nanostructures which can enter the cell easily and located in mitochondria. In addition, after evaluating the optical properties and toxicity of the probe AIE-CDs, the monitoring and imaging application of hypochlorite in living cells and zebrafish probes are successfully realized, suggesting the potential of probe AIE-CDs as a tool for biological applications.

Anion exchange membranes (AEMs) with a high ion exchange capacity, striking water uptake and excellent dimensional stability were prepared via an internal crosslinking networks strategy. Internal crosslinking networks were formed by reacting 4,4′-bipyridine with brominated poly (2,6-dimethyl-1,4-phenylene oxide) (BPPO). 4,4′-bipyridine not only provides a functional group but also comprises a cross-linking agent without requirements of post-functionalization. The variation of the 4,4′-bipyridine amount into the casting polymer solution was explored to regulate the performance of the anion exchange membranes, and the membrane properties were evaluated by AFM, ion exchange capacity (IEC), water uptake, the linear expansion ratio, tensile strength, thermal stability, membrane area resistance and electrodialysis experiments, etc. The results showed that the cross-linked membrane with the IEC of 1.98 mmol/g has much more outstanding dimensional stability (water uptake: 11.68%; swelling ratio: 3.8%) than non-cross-linked BPPO-Tri membrane (water uptake: 53.26%; swelling ratio: 7.71%) and commercial Neosepta AMX membrane (water uptake: 60.29%; swelling ratio: 5.08%), at the high temperature (50 °C). When being applied in ED application, the cross-linked BPPO-20 membrane (NaCl remove: 59.7%; energy consumption: 5.97 kWh/kg NaCl) exhibits slightly higher desalination efficiency and lower energy consumption than commercial Neosepta AMX membrane (NaCl remove: 58.3%; energy consumption: 6.51 kWh/kg NaCl), suggesting its promising application in ED.

A new fluorescent probe (ABPA) based on 1,8-naphthalimide, which designed on the “receptor1-fluorophore-spacer-receptor2” model and employed conjugated addition/cyclization sequence mechanism for Cys detection was reported. The probe shows high selectivity and sensitivity for cysteine (Cys) over other amino acids including the similar structured homocysteine (Hcy) and glutathione (GSH). It displays a highly sensitive fluorescence emission to Cys with a detection limit of 0.12 μM (S/N = 3), which is far below the normal level of Cys (30–200 μM) in living cells. Furthermore, ABPA was successfully applied to bioimage intracellular Cys in living cells with low cytotoxicity.

Surface modification of anion exchange membranes (AEMs) by attaching a negatively charged layer is the main method for preparing monovalent anion selective membranes. However, tremendous increase of membrane resistance and poor long term stability of the modified membranes face great challenges. In this work, a photosensitive molecule (4,4-diazostilbene-2,2-disulfonic acid disodium salt (DAS)) was infiltrated into the membrane surface and immobilized in the structure by cross-linking under UV irradiation. This method introduced negative charge to the surface layer of the AEMs without increasing membrane thickness, leading to high performance membrane with high monovalent anion selectivity. The optimized membrane (D-5) shows the highest perm-selectivity of 11.21, which is superior to the commercial selective membrane Selemion® ASV and previously reported monovalent anion selective AEMs. Furthermore, the newly developed membrane exhibits excellent long-term stability, which can maintain constant selectivity during the 80 h ED experiment. This article is protected by copyright. All rights reserved.

The near-infrared (NIR) fluorescent probe for rapid, highly sensitive and selective detection of cysteine (Cys) has great significance in both biological and environment sciences. In this work, a novel and specific dicyanoisophorone-based NIR probe for Cys was developed. This probe features remarkably large Stokes shift, with turn-on fluorescence property for highly sensitive and selective detection of Cys over other amino acids including the similar structured homocysteine (Hcy) and glutathione (GSH). The probe based on the conjugate addition-cyclization reaction, and has low detection limit of Cys. Furthermore, this probe shows great potential for Cys detection, which was successfully applied to bioimage Cys in living cells with low cytotoxicity.

Herein, we report a novel fluorescent probe based on coumarin to detect cysteine (Cys). The probe can react rapidly and selectively with Cys but not with the other amino acids. When the Cys was added to the solution of the probe, we could observe obvious color change from pale green to bright green. The detection limit of this probe for Cys was found to be 0.06 μM. Additionally, bioimaging of intracellular Cys by this probe was successfully applied in living cells, which indicating that this probe holds great potential for biological applications.

Aberrant O-glycosylation truncates O-glycans and is known to be closely associated with colorectal cancer (CRC), a major gastrointestinal tumor. CD44 is one of the highly post-transcriptionally modified O-glycoproteins participating in a series of physiological and pathobiological processes. In this research, we aimed to investigate whether CD44 expression in cells and exosomes can be influenced by disruption of Core 1-mediated O-glycosylation. Exosomes derived from LS174T and LSC human colon cancer cell lines were isolated from cell culture supernatant and pulled down using tetraspanin-specific antibody CD63 immunoaffinity magnetic beads. Identifications have been performed via transmission electron microscopy (TEM) and flow cytometry. CD63 immunoaffinity-purified exosomes are examined for CD44 expression by flow cytometric analyses. The percentages of CD44 in exosomes derived from abnormally O-glycosylated cells are significantly higher compared with those derived from normal ones, however, which is surprisingly contrary to the cellular expression levels of CD44. The secretion of truncated glycoproteins to the extracellular environment via microvesicles may be most likely its underlying mechanism. CD44 in exosomes might be a potential biomarker of aberrant O-glycosylation. This is the first study indicating that aberrant O-glycosylation can affect expression or delivery of O-glycoproteins via exosomes, which provides us some new sights in therapeutic strategies for human colon cancer.

Bacterial meningitis has a high mortality rate and can be challenging to diagnose and manage. This study aimed to evaluate the effect of diosmetin in a rat model of Streptococcus pneumoniae meningitis and to investigate the mechanism of action. Forty rats included a treatment group (n=30) that underwent intracisternal injection with S. pneumoniae, and a sham group (n=10) that underwent intracisternal injection with normal saline. In the treatment group, four days before the inoculation of the bacteria, rats were pre-treated with oral diosmetin 100 mg/kg (n=10) and 200 mg/kg (n=10), and the negative control was pre-treated with normal saline (n=10). Bacterial meningitis was confirmed one day after inoculation by cerebrospinal fluid (CSF) bacterial titer and neurological score. In rat brain tissue, levels of inflammatory mediators were determined by enzyme-linked immunosorbent assay (ELISA) and western blot for protein kinase B (Akt), phosphoinositide 3-kinase (PI3K), myeloid differentiation primary response 88 (MyD88), and nuclear factor-kappaB (NF-kappaB), and the TUNEL assay for apoptosis was performed. In the diosmetin-treated group compared with negative control group, the CSF bacterial titer and the level of pro-inflammatory mediators, and the neurological score, were significantly reduced (p

In this study, a novel carbon dots (CDs) was prepared by using citric acid and 1,2-diaminobenzene as raw materials via hydrothermal reaction. The obtained CDs showed a fluorescence turn-off response to divalent copper ion (Cu2+) with high selectively and sensitively which can be observed by the naked eye. The distribution of CDs is spherical with an average diameter about 2.89 nm, as observed by scanning electron microscopy (TEM) which could easily pass through the cell membrane and can be successfully located in mitochondria. In addition, the CDs was successfully applied to imaging Cu2+ in HeLa cells and zebrafish owing to its excellent optical performance and low toxicity.

A new 1,8-naphthalimide derivative (NAD) was synthesized and employed as a highly sensitive and selective probe for the detection of cysteine (Cys) and Cu2+. The terminal olefin of NAD could react with Cys and resulting in fluorescence quenching, with the adding of Cu2+, the schiff base unit of NAD could coordinate with Cu2+ and lead to a highly selective fluorescence “turn-on” response. The detection limits reached as low as 25 nM for Cys and 11 nM for Cu2+. In addition, the NAD probe can be further applied to cells imaging owing to its photostability and low cytotoxicity.

In this study, carbon dots (CDs) were first obtained by using solid phase reaction method (SPRM). Compared with other methods, SPRM shows remarkable advantages on simple, rapid, and large scale CDs' fabrication without post-treatment and solvent-free. In addition, the obtained CDs can be employed as ideal fluorescent Fe 3+ probe and fluorescent ink. By taking advantage of its low-cytotoxicity, the CDs can be further applied in cell imaging successfully. This strategy offers a simple and efficient approach for preparing CDs in large-scale and lays a foundation for its further multi-purpose application.

Hyperbranched aromatic-aliphatic polyester HBPE-BBA was synthesized by modifying the periphery of a second-generation hyperbranched polyester (HBPE) with benzimidazole (BBA) end groups. HBPE-BBA showed interesting self-assembly behaviors, and retained one-dimensional nano bead-on-string fibers and two-dimensional helical nanocoil morphologies in different solvents. The fluorescence results indicated that HBPE-BBA exhibited remarkable selectivity for Fe3+ and fused ring compounds.

This paper developed a new fluorescent rhodamine-based derivatives (RAD) probe for highly sensitive and selective detection of Cu2+ and L-Methionine (L-Met). The detection limits can reach as low as 12 nM for Cu2+ and 5 nM for L-Met, In addition, the RAD probe can be further applied to cell imaging owing to its photostability and low cytotoxicity.

As an important reactive carbonyl compound, formaldehyde (FA) existing in various parts of the organism and plays an important role in cognitive ability and memory formation. However, abnormal concentrations of FA could cause many diseases. Herein, a novel 1,8-naphthalimide derivative fluorescent probe (NID) for detecting FA was rationally designed and synthesized. Probe NID showed a rapid response (within 8 s) towards FA with visual detection. More importantly, NID can be used to image FA in MCF-7 cells, which demonstrated its suitability for practical applications of biological systems with low cytotoxicity.

A new achiral aggregation-induced emission enhancement (AIEE)-active conjugated polymer P1 incorporating tetraphenylethene (TPE) and metal binding part structure was designed and synthesized. The polymer emits bright green fluorescence in the mixture of tetrahydrofuran (THF) and water. The coordination between Cu2+ and P1 causes fluorescence quenching from green to almost no emission, and the resulting polymer-Cu2+ complex responds to histidine selectively over other competing amino acids with obvious fluorescence recovery. In addition, the distinct circular dichroism (CD) response proved the success of the enantioselective recognition of P1-Cu2+ complex towards the enantiomers of histidine.

The recent rise of metacomposites offered a new research strategy for electromagnetic shielding materials owing to their negative electromagnetic parameters, such as negative permittivity. Herein, we prepared silver/silicon nitride (Ag/Si3N4) metacomposites with tunable negative permittivity by a facile impregnation-calcination process, and explored their electrical conductivity, permittivity and electromagnetic shielding properties. As the Ag content increased, formative metal networks in the composites rendered their conductivity characteristic changing from a hopping conductivity to a metal-like conductivity. Tunable negative permittivity behavior combined with enhanced shielding effectiveness (SE) was observed at 2–18 GHz in the metacomposites with high Ag contents. The plasma-like negative permittivity was accounted for by a low frequency plasmonic state of free electrons in the inductive Ag networks, and the frequency band and absolute magnitude of negative permittivity could be adjusted by controlling Ag content, which was well described by Drude model. The average total SE of our obtained metacomposite could reach ~30 dB, and the reflection was the primary shielding mechanism, which was attributed to the intense impedance mismatching stemmed from the negative permittivity. Our work opens up the possibility of designing metacomposites for promising electromagnetic shielding materials, promoting their application in microwave field.

A new N-doped carbon dots (NCDs) could be prepared by using the microwave-assisted technique within 10 min without the need for any solvent or catalyst. The NCDs exhibited a highly sensitive electrochemical response toward dopamine (DA) in Phosphate Buffered Saline (PBS) (pH=6.5). The detection limit of DA was calculated by differential pulse voltammetry (DPV) as low as 1.2×10(-9) mol/L with a linear dynamic range of 5.0×10(-8) to 8.0×10(-6) mol/L. These results suggested that this new NCDs could be effectively used for the direct and rapid detection of trace levels of DA in human serum and urine samples.

In this study, two water-soluble fluorescent probes based on pyrrolo[2,1- a ]isoquinoline derivatives ( 4a and 4b ) were synthesized and characterized by IR, 1 H NMR, 13 C NMR, MS spectra and elemental analysis for the first time. The obtained compounds ( 4a and 4b ) showed fluorescent ‘turn-on’ phenomenon to Ag + with limits of detection (LOD) of 0.6 μM ( 4a ) and 0.8 μM ( 4b ) (S/N=3), respectively.

The structurally controllable hyperbranched HBPE–CIDAs (HBPE modified with CIDA units) were synthesized by modifying the periphery of the second generation hyperbranched polyester (HBPE) with 1-cyanoindolizine-3-carboxylic acid (CIDA) groups via a one-pot synthesis. The structures and self-assembly behaviors of HBPE–CIDAs were established by combined studies of FFT-IR, NMR, TEM, SEM, AFM and XRD. Furthermore, host–guest recognition of HBPE–CIDAs was investigated by fluorescence studies. The results indicated that the HBPE–CIDA4 nanospindles have weaker response to various metal ions while having better selectivity to anthracene through π–π stacking interactions than the HBPE–CIDA1 nanospheres.

In this study, N-doped carbon dots (NCDs) could be prepared by using glycerol as the carbon source and ethylenediamine as a nitrogen doped molecule through a one-step microwave irradiation method. The resulting NCD probes could exhibit linear fluorescence response to Pb2+ at a detection limit as low as 15.0 nM, which could be applied for trace levels of direct pb2+ recognition.

The low content of phenolic groups limits the application of lignin-based materials as biosorbents for the removal of metal ions. In this work, a novel gallic acid-grafted-lignin (GAL, 4.43 mmol/g hydroxyl group) biosorbent was designed by introducing gallic acid moieties to replace the hydroxyl groups of lignin. These grafted polyphenolic groups provide additional sites for the adsorption of metal ions. The structure of GAL was characterized by FT-IR, 31P NMR, and 13C NMR spectroscopy. The adsorption properties of GAL for Pb(II) ions were investigated under batch conditions. Kinetic and isothermal adsorption processes could be well-described by the pseudo-second order kinetic model and Langmuir isothermal model, respectively. The grafting of polyphenolic groups onto lignin increased the maximum adsorption capacity of the adsorbent for Pb(II) (119.1 mg/g). The adsorption thermodynamics indicated that the adsorption process was endothermic and spontaneous. In addition, GAL could selectively adsorb Pb(II) with a selectivity coefficient (k) at 1.89 in the presence of coexisting metal ions from aqueous solution. The high adsorption capacity and selectivity for Pb(II) by GAL, together with its environmental compatibility, enable this material to act as a promising biosorbent for removing heavy metal ions from polluted water.

Stromal cell-derived factor 1 (SDF-1)/CXCR4 ligand-receptor axis is widely recommended as an attractive target for cancer therapy. Meanwhile, epithelial-mesenchymal transition (EMT) process is linked to disease pathophysiology. As one of inhibitors of apoptosis proteins, survivin is implicated in the onset and development of cancer. In the present study, we tried to determine the cause-effect associations between SDF-1/CXCR4 axis and survivin expression in glioblastoma U-251 cell line. Survivin activation and inhibition were induced with exogenous SDF-1 and survivin small interfering RNA (survivin siRNA), respectively. Western blot was used to detect relevant proteins in SDF-1/CXCR4 axis. Western blot analysis revealed that survivin expression in U-251 increased in a dose- and time-dependent manner in response to SDF-1 treatment. However, the interference with MEK/ERK and PI3K/AKT pathway prohibited SDF-1-induced survivin up-regulation. Importantly, survivin knockdown abrogated cell cycle progression and the expression of snail and N-cadherin, compared with non-transfectants. In conclusion, the present study shows that SDF-1 up-regulates survivin via MEK/ERK and PI3K/AKT pathway, leading to cell cycle progression and EMT occurrence dependent on survivin. The blockade of survivin will allow for the treatment of glioblastoma.

Some new 4H-pyrrolo[1,2-a]benzimidazoles(2a–2f) have been synthesized. The structures of these compounds were confirmed by IR, 1H NMR, mass spectroscopy and elemental analysis. Compound 2a was further confirmed by X-ray diffraction. The in vitro antimicrobial activities of these compounds were determined against some gram-positive bacteria, gram-negative bacteria and fungi and their drug-resistant isolates in comparison with standard drugs. Antimicrobial results indicate that compounds 2c, 2d and 2e show moderately active antibacterial properties, their minimum inhibitory concentrations are from 12.5 μg/mL to 125 μg/mL. In the series, the most active compound against C. albicans is compound 2f with an MIC value of 31.25 μg/mL.

Sorafenib has been systemically utilized to therapy the advanced hepatocellular carcinoma (HCC). Natural killer cells (NKs) are important cytotoxic innate lymphocytes, which can exert effector functions especially in liver and tumor. However, how Sorafenib affects the function of NKs remains to be elucidated. Here, we utilized the subcutaneous and in situ tumor bearing mice with mouse hepatoma cell line hepa 1-6. At the endpoint, the number and function of NKs in blood, liver, TDLN, and tumor were explored using FACS, ELISA, WB, etc. To confirm the direct effects of Sorafenib on NKs, the NKs were sorted using FACS, which were then stimulated with Sorafenib to detect the functions and the relevant mechanisms using qPCR, western blot, and FACS in vitro. Finally, we found that Sorafenib led to a significant block of tumor progression, but reduced the number of NK cells through suppressing the proliferation of NK cells. This phenotype made us study the terminal function of NK cells, revealing that Sorafenib could decrease the production of effector molecules and cytokines, such as perforin, granzyme B, TNF-α, IFN-γ, etc. Besides, p-ERK1/2 in NK cells was inhibited after treatment with Sorafenib, and a similar tendency of NK cells could be achieved using ERK1/2 inhibitor. Collectively, our data suggested that Sorafenib functioned as a critical inhibitor that controlled the number and function of NK cells through inhibiting ERK1/2.

Smart gating membranes with self-regulating nanopores/nanochannels are highly desirable for water gating and separation of small molecules. Based on the nanochannels in the graphene oxide (GO) membrane, we designed positive thermo- and negative pH-responsive GO/hydrogel composite membranes (GOGMs) through a simple filtration-accumulation of GO sheets and hydrogels. The shape-flabby hydrogels can be perfectly inlaid between two GO sheets by changing their shape, and also act as a bond between GO and substrates. Thermo- and pH-responsive hydrogels embedded between the GO sheets impart adjustable water channels to the GO membrane. The channel tunability of hydrogel-studded GO membrane derives from the size conversion of hydrogel and the constant layer spacing of GO sheets. The hydraulic permeability of GOGMs was explored within the wide pH range of 2–6 and the temperature interval of 20–44 °C. The results revealed that the hydraulic permeability of the GOGMs can be reversibly adjusted with a high thermo- and pH-responsive gating coefficients. The GOGMs with self-regulated channels have various permeability properties for small molecules under different conditions. Moreover, the membrane thickness and the ratio of microgel to GO both have an effect on the water permeation and response performance of the GOGMs. These environmental stimuli-responsive membranes with thermo- and pH-responsive channels has numerous potential for applications in smart gating systems, liquid-based controlled release systems and smart separation systems.

In this study, new carbon nanomaterial N-doped carbon dots (NCDs) were obtained via a one-step hydrothermal method using isoleucine and citric acid as carbon precursors. TEM results showed that the NCD diameters were not uniform but distributed in the 6–15 nm range, with an average value of 10 nm. The maximum emission wavelength of the obtained NCDs was 415 nm with an excitation wavelength of 370 nm. Under optimal conditions, the nanoparticle can be used as sensors and exhibited a ‘turn-off’ fluorescence response to Fe 3+ , with a good linear relationship of ( F / F 0 ) versus Fe 3+ over the concentration range of 0–20 μmol/L.