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Mercury (Hg) pollution can negatively impact ecosystems, and there is a need for simple Hg2+ monitoring platforms. Here, a dual-ligand fluorescence probe based on terbium-organic gels (Tb-L 0.2 P 0.8 MOGs) was constructed for efficient Hg2+ detection. Tb-L 0.2 P 0.8 MOGs were developed through a facile room-temperature gelation method, showing two emission peaks derived from luminol and Tb3+ at 424 nm and 544 nm, respectively. The aggregation-induced emission (AIE) effect between luminol and Tb3+ led to luminol with blue fluorescence. However, Hg2+ could dramatically quench the fluorescence signal of luminol at 424 nm because of the intense coordination interaction of Hg2+ with luminol and photo-induced electron transfer (PET). The Phen ligand could sensitize the luminescence of Tb3+ and offer a reference fluorescence, thus resulting in a unique ratiometric fluorescence response toward Hg2+. This novel nanoprobe had excellent linearity with Hg2+ concentrations range of 0.1–30 μM; the detection limit was 3.6 nM. The analysis of real samples showed the potential application of MOGs for measuring Hg2+ in porphyra and tap water. Mixed ligands were introduced for high-efficiency strategies to improve the analytical performance by regulating the emission behavior of MOGs. [Display omitted] • Dual-ligand Tb-L 0.2 P 0.8 MOGs with 2D structure were prepared through a room-temperature gelation method. • Tb-L 0.2 P 0.8 MOGs exhibited two emission peaks deriving from luminol and Tb3+ at 424 nm and 544 nm. • AIE effect between luminol and Tb3+ made Tb-L 0.2 P 0.8 MOGs exhibit intense blue fluorescence. • The coordination of Hg2+ with luminol and PET process caused the fluorescence quenching of luminol. • Tb-L 0.2 P 0.8 MOGs showed ratiometric fluorescence response toward Hg2+ in porphyra and tap water. [ABSTRACT FROM AUTHOR]

The application of nanostructures to design fluorescence resonance energy transfer (FRET) based sensing platforms has been greatly concerned with the demand for sensitive and selective detection of biomolecules. Here, a novel sensitive turn-on fluorescence strategy based on the FRET mechanism has been designed for hyaluronidase (HAase) detection through the modulation of Cu 2-x Se@HA-Rh6G nanoprobe fabricated by self-assembly of rhodamine 6G (Rh6G) together with Cu 2-x Se@HA nanoparticles through electrostatic adsorption. The Cu 2-x Se@HA had extensive localized surface plasma resonance (LSPR) absorption in the wide range of ultraviolet (UV) to near-infrared (NIR) wavelengths and showed good light capture characteristics, which can be acted as good acceptors in the FRET interactions with Rh6G, inducing its efficient fluorescence quenching. In the presence of HAase, the FRET process was disrupted and the fluorescence signal was recovered. In the range of 0.1–10.0 U/mL, the fluorescence recovery of Rh6G showed a good linear relationship with the concentration of HAase, and the detection limit was 0.06 U/mL. The sensing platform has been used for HAase detection in real urine samples and cancer cells imaging. An off-on fluorescence nanoprobe for hyaluronidase (HAase) has been developed through the modulation of FRET between plasmonic Cu 2-x Se@HA and rhodamine 6G. And the proposed sensing platform is applicable for the sensitive detection of HAase in real urine samples and for the imaging of cancer cells with HAase overexpression. [Display omitted] • Broad spectrum Cu 2-x Se@HA and rhodamine 6G were used to construct a FRET nanoprobe. • The FRET between Cu 2-x Se@HA and rhodamine 6G can be modulated by the hyaluronidase. • Fluorescent turn-on detection of hyaluronidase in urine samples has been realized. • Targeting imaging of hyaluronidase in cancer cells has been realized. [ABSTRACT FROM AUTHOR]

Ischemic stroke is a devastating complication of bone fracture. Bone fracture shortly after stroke enhances stroke injury by augmenting inflammation. We hypothesize that bone fracture shortly before ischemic stroke also exacerbates ischemic cerebral injury. Tibia fracture was performed 6 or 24 hours before permanent middle cerebral artery occlusion (pMCAO) on C57BL/6J mice or Ccr2RFP/+Cx3cr1GFP/+ mice that have the RFP gene knocked into one allele of Ccr2 gene and GFP gene knocked into one allele of Cx3cr1 gene. Behavior was tested 3 days after pMCAO. Infarct volume, the number of CD68+ cells, apoptotic neurons, bone marrow-derived macrophages (RFP+), and microgila (GFP+) in the peri-infarct region were quantified. Compared to mice subjected to pMCAO only, bone fracture 6 or 24 hours before pMCAO increased behavioral deficits, the infarct volume, and the number of CD68+ cells and apoptotic neurons in the peri-infarct area. Both bone marrow-derived macrophages (CCR2+) and microglia (CX3CR1+) increased in the peri-infarct regions of mice subjected to bone fracture before pMCAO compared to stroke-only mice. The mice subjected to bone fracture 6 hours before pMCAO had more severe injury than mice that had bone fracture 24 hours before pMCAO. Our data showed that bone fracture shortly before stroke also increases neuroinflammation and exacerbates ischemic cerebral injury. Our findings suggest that inhibition of neuroinflammation or management of stroke risk factors before major bone surgery would be beneficial for patients who are likely to suffer from stroke. [ABSTRACT FROM AUTHOR]

Background: The transcription factor forkhead box D3 (FOXD3) plays important roles in the development of neural crest and has been shown to suppress the development of various cancers. However, the expression and its potential biological roles of FOXD3 in high-grade gliomas (HGGs) remain unknown. Methods: The mRNA and protein expression levels of FOXD3 were examined using real-time quantitative PCR and western blotting in 23 HGG and 13 normal brain samples, respectively. Immunohistochemistry was used to validate the expression FOXD3 protein in 184 HGG cases. The association between FOXD3 expression and the prognosis of HGG patients were analyzed using Kaplan-Meier survival curves and Cox proportional hazards regression models. In addition, we further examined the effects of FOXD3 on the proliferation and serum starvation-induced apoptosis of glioma cells. Results: In comparison to normal brain tissues, FOXD3 expression was significantly decreased in HGG tissues at both mRNA and protein levels. Immunohistochemistry further validated the expression of FOXD3 in HGG tissues. Moreover, low FOXD3 expression was significantly associated with poor prognosis in HGG patients. Depletion of FOXD3 expression promoted glioma cell proliferation and inhibited serum starvation-induced apoptosis, whereas overexpression of FOXD3 inhibited glioma cell proliferation and promoted serum starvation-induced apoptosis. Conclusions: Our results indicated that FOXD3 might serve as an independent prognostic biomarker and a potential therapeutic target for HGGs, which warrant further investigation. [ABSTRACT FROM AUTHOR]

Dynamic DNA nanodevices-based assembly is currently well developed for a broad range of analytical applications. However, some problems persist, such as false positives, nuclease digestions, and exclusive interferences with single signal in complex cellular environment. Herein, we have established a method for imaging cellular miR-155, where it induced assembly of two tetrahedral DNA frameworks (TDFs), TDF-1 and TDF-2, both of which had four fluorescence modified hairpins (Cy3 for TDF-1 and Cy5 for TDF-2, respectively) at each angle, into polymeric tetrahedral DNA frameworks (PTDFs). The formation of PTDFs was greatly dependent on miR-155 overexpressed in breast cancer cells since miR-155 drove catalytic hairpin assembly (CHA) reaction by opening the hairpins at the vertices of TDF-1 to hybridize with TDF-2. Upon the completion of hybridization, the miR-155 was released, starting the next cycle of the CHA reaction. Measurements of atomic force microscopy (AFM) and Förster resonance energy transfer (FRET) showed that the formation of PTDFs occurred owing to the multivalent assembly of TDF-1 and TDF-2. By utilizing the formation of PTDFs, miR-155 was detected in a linear range from 0.5 nM to 30 nM with a 0.35 nM limit of determination, enabling the successful imaging of endogenous miR-155 in live cells through the FRET signal from Cy3 to Cy5. These studies demonstrated that this method significantly strengthened the resistance nuclease to digestion and stable ability with exclusive interference. Our present work has the following three advantages: • A dynamic assembly system that integrated tetrahedral DNA frameworks TDFs with catalytic hairpin assembly reaction was proposed for ratiometric sensing miR-155. • TDFs with higher capacity of hairpins exhibited excellent internalization and nuclease-resistant ability for the enhanced FRET signal, which is favorable for minimizing interferences and keeping stable in biological environment. • Target miR-155 could circularly trigger polyvalence assembly of TDF-1 and TDF-2, which is available for dynamic imaging intracellular miR-155 with higher selectivity and sensitivity. [ABSTRACT FROM AUTHOR]

Highlights: [•] Reaction between lignin model compound and ClO2 is researched by UV–vis. [•] Reaction mechanism of lignin model compound oxidation by ClO2 is derived. [•] Kinetics for lignin model compound oxidation by ClO2 is propose. [•] Bring new door open for resolving the environmental pollution in ECF bleaching. [ABSTRACT FROM AUTHOR]

Abstract: We have developed a simple, rapid and label-free sensor for the essential biological OH radicals based on the fluorescence quenching of DNA-templated Ag nanoclusters (DNA-Ag NCs). The OH radicals generated from the Fenton reagent attack and cleave the DNA template, which disturbs the microenvironments around Ag NCs, resulting in spontaneous aggregation due to the lack of stabilization and further the quenching of the Ag NCs fluorescence. These changes in fluorescence intensity allow sensing of OH radicals with good sensitivity and selectivity under optimal conditions. The sensor can be also applied for quantifying the radical scavenging action of antioxidants. Various characterizations including absorption spectra, fluorescence lifetimes, light scattering (LS) spectra, transmission electron microscopy (TEM), dark field light scattering imaging, and circular dichroism (CD) spectrometry have been employed to illustrate the proposed sensing mechanism. Further investigations demonstrate that the fluorescent probe could penetrate into intact cell membranes to selectively detect intracellular OH radicals induced by the phorbol myristate acetate (PMA) stimulation. These advantageous characteristics make the fluorescent DNA-Ag NCs potentially useful as a new candidate to monitor OH in broad biosystems. [Copyright &y& Elsevier]

Conventional methods for the detection of the sulfur mustard poisoning metabolic marker, thiodiglycol (TDG), require expensive instruments and reagents as well as professional operators. To address these problems, a novel test strip based on a molecularly imprinted sensitive membrane (MIM) was developed in this work for point-of-care (POC) detection of TDG. The TDG test strip was prepared conveniently by coating molecular imprinted polymers (MIPs) on a nitrocellulose membrane. When the sample contained TDG, the MIPs could specifically bind with TDG. A great number of AuNPs (AuNPs) could then be adsorbed on the test strip via the formation of an Au–S bond between TDG and AuNPs, giving the test strip the obvious red color of AuNPs. In the absence of TDG, the test strip exhibited much lighter color because it could not adsorb AuNPs. By monitoring the color change of the test strip, TDG could be detected from 1.0 ng/mL to 100.0 μg/mL with a detection limit of 0.23 ng/mL (3σ) under the optimal conditions (the molar ratio of TDG to MAA was 1:2; the eluent was chloroform; the elution time was 50 min; the reaction time between MIPs and TDG was 15 min; the adsorption time of AuNPs was 40 min; the temperature of the reaction system was 35 °C). This method has excellent selectivity and has been used to detect TDG in urine, showing great potential for POC detection of TDG in clinical samples. In this study, a novel molecular imprinting test strip based POCT method for the detection of thiodiglycol (TDG) by using gold nanoparticles (AuNPs) as colorimetric reporters was reported. [Display omitted] • A novel and stable molecularly imprinted test strip was developed for point-of-care (POC) detection of TDG. • By using AuNPs as colorimetric reporters, TDG could be detected through naked eyes straightforwardly. • This method has excellent selectivity and has been used to detect TDG in urine. [ABSTRACT FROM AUTHOR]

The different shapes of titanium carbide (TiCx) grains formed at different growth stages of self-propagating high-temperature synthesis (SHS) were obtained in the quenched sample. The shape evolution of the TiCx grains and the growth mechanism are discussed. As the highly substoichiometric TiCx nucleates at the initial stage of the SHS, the (111) surfaces become stable and the TiCx grains nucleate as octahedra. With an increase of the TiCx stoichiometry, the free energy of the (111) surfaces increases. Hence, the area of the (111) surfaces on the TiCx grains decreases gradually while the (100) surfaces are exposed. The growth shape of the TiCx grains turns to truncated-octahedron. Moreover, when the combustion temperature during the SHS exceeds a certain value (about 1800 °C), the (100) surfaces of the TiCx grains turn round and these rounded (100) regions grow and coalesce with further increasing of the TiCx stoichiometry. The growth shape of the TiCx grains then turns to close-to-sphere. TiCxgrains with different morphologies formed during self-propagating high-temperature synthesis (SHS) and the corresponding Wulff plot are shown. The morphologies of TiCx grains formed at different SHS reaction stages were investigated, and the shape evolution process and the growth mechanism are discussed. [ABSTRACT FROM AUTHOR]

Abstract: The TiB2–AlN and TiB2–AlN–TiN ceramic matrix composites were successfully produced by self-propagating high-temperature synthesis (SHS) reactions from the Al–Ti–BN compacts through the manipulation of the Al reactant content. The effects of the Al content on the adiabatic and practical maximum combustion temperatures, wave velocity, phase composition and microstructure of the synthesized products, and reaction mechanism were investigated in detail. Thermodynamically and practically, the reaction was most exothermic for the Al content being 35.5wt.% in the reactants to produce only the dual TiB2–AlN phases. Kinetically, the reaction commenced with the formation of Al3Ti, and then proceeded with the interactions of the Al–Ti intermetallics/melts with BN to yield the AlN and TiB2 phases. The substantial reaction between the elemental Ti and BN into formation of TiN took place only in the low Al content samples. On the other hand, the presence of considerable amount of the TiN grains effectively inhibited the abnormal growth of the TiB2 grains, leading to very fine microstructures; whereas, the grain growth of TiB2 and AlN as well as their inhomogeneous distribution was enhanced by the increase in the Al reactant, while TiN was completely inhibited from development. [Copyright &y& Elsevier]

• Borosilicate glass immobilizing simulated actinides were synthesized. • The crystallization behavior of pressed powder and green pellet was investigated. • The relationship between the content of Ce3+/Ce4+ and chemical stability were revealed. • Borosilicate glasses nuclear waste forms have good chemical stability. A series borosilicate glasses containing three alkaline earth metals (Ca, Mg, Ba) and immobilized with ceria from low content (3 wt%) to exceed the solubility limit (20 wt%) were prepared by the solid-state melt method. The results of phase separation revealed by SEM, XRD and EDX show that simulated waste CeO 2 loading was below 13 wt%, and the excess part was tightly connected with glass. The controlled heat treatment of the quenched blocks and the green pellets was conducted to explore the effect of ceria content of the system on the crystalline state. The solidified waste forms with a ratio of Ce3+/Ce4+ close to 1 have the lower leaching rate after 28 d (LR Si =9.84 × 10−4 g m−2 d−1, LR Ca =6.68 × 10−4 g m−2 d−1) and LR Ce of all samples is always maintained in the order of magnitude of 10−5 g m−2 d−1, suggesting that cerium doped multiple alkaline earths borosilicate glasses have higher chemical stability. [ABSTRACT FROM AUTHOR]

Preeclampsia (PE) is a pregnancy-specific disorder characterized by the onset of hypertension and proteinuria with onset after the 20th week of gestation. The pathogenesis of PE is attributed to increased trophoblast cell death and poor trophoblast migration/invasiveness. This study investigates the function of microRNA-23a (miR-23a) in PE and its effects on migration and invasion of trophoblast cells HTR-8/SVneo. We found higher expression of miR-23a in placental tissue samples from PE pregnant women compared to samples from normal pregnant women. Enhancing miR-23a expression by its specific mimic reduced HTR-8/SVneo cell migration and invasion and increased HTR-8/SVneo cell apoptosis. The dual-luciferase reporter gene assay revealed miR-23a binding with HDAC2. We found that HDAC2 was poorly expressed in placental tissue samples from PE pregnant women, and its expression correlated inversely with miR-23a expression. HTR-8/SVneo cells showed diminished HDAC2 expression upon miR-23a elevation and increased HDAC2 expression upon miR-23a inhibition. Lentivirus-mediated HDAC2 knockdown mimicked the effects of miR-23a on HTR-8/SVneo cells and led to NF-κB activation. Similarly, HDAC2 overexpression and NF-κB inhibition both abrogated the effects of miR-23a on HTR-8/SVneo cells, suggesting that miR-23a reduced HTR-8/SVneo cell migration and invasion and increased HTR-8/SVneo cell apoptosis by HDAC2 inhibition and NF-κB activation. In summary, these results support a novel role of miR-23b in invasion and apoptosis of trophoblast cells, and imply that targeting miR-23b may be a new avenue for treating PE. [ABSTRACT FROM AUTHOR]

Sodium zirconium phosphate (NaZr 2 (PO 4) 3 , NZP) family ceramics were considered as a potential host matrix for the immobilization of nuclear waste. In this study, the dense Sr-incorporated NZP ceramics with the formula of Na 1-2 x Sr x Zr 2 (PO 4) 3 (x = 0, 0.1, 0.2, 0.25, 0.3, 0.4, and 0.5) were fabricated by microwave-assisted solid-state reaction method. The phase evolution, densification behavior and chemical stability of the as-prepared samples were systematically investigated by XRD, Rietveld refinement, Raman, SEM-EDS and PCT method. The results demonstrated that Na in the NZP lattice could be substituted by the simulated fission product Sr, and the phase composition gradually changed from NZP to Sr 0.5 Zr 2 (PO 4) 3 (SrZP) with the increase of Sr content. The samples presented high densification and uniform elements distribution after microwave sintering at 1100 °C for 2 h. Moreover, the as-prepared samples exhibited the superior chemical stability. The normalized elemental leaching rate of Sr, Na, P, and Zr were 10−3, 10−4, 10−3, and <10−7 g⋅m−2⋅d−1, respectively. [ABSTRACT FROM AUTHOR]

• The detoxified Cr-added FMB geopolymer was prepared by hydrothermal processing. • The detoxified Cr can be fixed in the skeleton structure of FMB geopolymer. • The sample still possesses higher compressive strength after hydrothermal processing. • The products exhibit excellent Cr(VI) leaching toxicity. The detoxification and disposal of hexavalent chromium [Cr(VI)] is of real importance to the ecological environment protection and human being health. In this paper, Cr(VI) was in advance reduced to trivalent chromium [Cr3+ by Fe2+ and was immediately immobilized in a "fly ash-metakaolin" based (FMB) geopolymer through alkaline activation and hydrothermal processing. The phase structure and microstructure of the as-prepared detoxified Cr-added FMB geopolymer were investigated by XRD, FT-IR and SEM. The compressive strength and Cr(VI) leaching toxicity of the samples were also systematically investigated. The results showed that the phase compositions of the samples were mainly composed of amorphous phase, several weak crystalline phases of quartz, gismondite and sodium chloride after hydrothermal processing. The detoxified Cr can be fixed as the form of chemical bonding in the skeleton structure of FMB geopolymer. In addition, the compressive strength test results revealed that the compressive strength was mainly affected by the contents of Cr addition and reducing agent. Importantly, the extremely low leaching concentration of Cr(VI) suggested that the Cr-added FMB geopolymer prepared by hydrothermal processing possessed excellent Cr(VI) leaching toxicity, and the reduced Cr3+ was difficultly reoxidized to Cr(VI) after being immobilized in the FMB geopolymer. [ABSTRACT FROM AUTHOR]

The aim of this study was to uncover the underlying mechanisms of cervical cancer progression and provide potential therapeutic targets for its treatment in clinic. Real-Time qPCR was used to determine the expression levels of Linc00483, miR-508-3p and RGS17 mRNA in cervical cancer tissues and cell lines. Terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick-end labeling (TUNEL) assay was conducted to determine cell apoptosis. Western Blot was performed to detect protein expression levels. Wound healing and Transwell assay were employed to determine cell migration and invasion respectively. Online software (TargetScan, miRDB and miR TarBase) were used to predict the regulating mechanisms of Linc00483, miR-508-3p and RGS17, which were validated by dual-luciferase reporter gene system. In vivo tumor-bearing mice models were established to validate the cellular results. Linc00483 aberrantly overexpressed in both cervical cancer tissues and cell lines comparing to the Control groups. Knock-down of Linc00483 inhibited cervical cancer cell proliferation, invasion as well as migration, and promoted cell apoptosis. In addition, miR-508-3p was identified as the downstream target of Linc00483, and miR-508-3p inhibitor abrogated the inhibiting effects of downregulated Linc00483 on cervical cancer cell viability. Furthermore, the expression levels of Linc00483 was positively correlated with RGS17 in the clinical samples and overexpressed Linc00483 increased RGS17 expression levels in cervical cancer cells by sponging miR-508-3p. The in vivo experiments showed that knock-down of Linc00483 inhibited cervical cancer cell tumorigenesis and lung metastasis in mice models. Knock-down of Linc00483 inhibited the development of cervical cancer by regulating miR-508-3p/RGS17 axis. [ABSTRACT FROM AUTHOR]