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• Patients with acute tandem vertebrobasilar artery occlusion are difficult to treat. • Endovascular combined with vertebral artery endarterectomy is a feasible treatment. • Until now, no report about this technology to treat these patients. To evaluate the safety and efficacy of endovascular treatment combined with vertebral artery endarterectomy in patients with acute tandem vertebrobasilar artery occlusion. From April 2017 to March 2019, three patients with acute basilar artery occlusion combined with ostial vertebral occlusion in our institution were enrolled in the study. They underwent endovascular treatment combined with vertebral artery endarterectomy. The clinical, technical and functional outcomes of the patients were retrospectively analysed. All three patients in the study underwent complete recanalization. The modified Thrombolysis in Cerebral Infarction (mTICI) grade was 2b/3 in all patients. The modified Rankin Scale (mRS) score was 0–2 for the three patients at 3 months. Follow-up CT scans revealed no cerebral haemorrhage, and no patients died during follow-up. All patients achieved good clinical outcomes after the combined treatment. Endovascular treatment combined with vertebral artery endarterectomy is a feasible method to treat patients with acute basilar artery occlusion combined with ostial vertebral occlusion, especially when the guidewire cannot pass through the ostium of the dominant vertebral artery occlusion. [ABSTRACT FROM AUTHOR]

Lead zirconate titanate (PZT) films have been deposited on Ti–Pt/Ti/SiO 2 /Si(100) alloy substrates by sol-gel process. The purpose of the present study was to examine the Ti content in the Ti–Pt alloy layers-dependent preferred orientation and electrical behaviors of PZT films. X-ray diffraction (XRD) shows that Ti–Pt alloy electrodes induces texture transition from (100) to (111), and the maximum peak of (100) and minimum peak of (111) are obtained in the sample on Ti–Pt alloy layer with a sputtering power of 12.5 W/150 W. The film deposited on Ti–Pt alloy layer with a sputtering power of 12.5 W/150 W exhibits a reduced oxygen vacancies concentration, which results in a maximum ε of 1224.25, an enhanced 2 P r of 40.5 μC/cm2, and a relative decreased 2 E c of 108 kV/cm. Therefore, it can be concluded that the Ti–Pt alloy layers with an appropriate Ti content play a very critical role for the preferred orientation, microstructure, and improved electrical properties of the PZT films. [ABSTRACT FROM AUTHOR]

The activation of stimulator of interferon genes (STING) plays a key role for provoking effective innate and adaptive immunity, yet is constrained by the limited clinical translation of STING agonists. Herein, we construct a smart DNA sponge to deliver STING agonists for robust cancer immunotherapy via the synergistic activation of innate immune pathways. The compact DNA sponge (Mn-CpG), assembling through a simple rolling circle amplification reaction, is encoded with numerous STING agonist (Mn2+) and toll-like receptor 9 (TLR9) agonist (CpG oligodeoxynucleotide) and allows their on-demand cellular delivery We show that Mn-CpG sponge can trigger the synergistic type I interferon response and robust T cell priming through a convenient coordination of different signaling pathways. In a poorly immunogenic breast cancer model, the method achieves the boosted immune responses with significantly inhibited tumor growth and metastasis. [Display omitted] • The compact DNA sponge realizes the on-demand cellular delivery of STING and TLR9 agonists into antigen-presenting cells. • This system actualizes two innate immune stimuli to achieve effective antitumour immunity with decreased autoimmune toxicity. • It provides a simple yet powerful tactic that renders DNA-based STING activation with synergistic innate immunomodulation. [ABSTRACT FROM AUTHOR]

Automatic and accurate identification of rolling bearing fault categories, especially for the fault severities and compound faults, is a challenge in rotating machinery fault diagnosis. For this purpose, a novel method called adaptive deep belief network (DBN) with dual-tree complex wavelet packet (DTCWPT) is developed in this paper. DTCWPT is used to preprocess the vibration signals to refine the fault characteristics information, and an original feature set is designed from each frequency-band signal of DTCWPT. An adaptive DBN is constructed to improve the convergence rate and identification accuracy with multiple stacked adaptive restricted Boltzmann machines (RBMs). The proposed method is applied to the fault diagnosis of rolling bearings. The results confirm that the proposed method is more effective than the existing methods. [ABSTRACT FROM AUTHOR]

Catalytic DNA circuit, a versatile synthetic molecular nanodevice, shows great potential for in vivo bioimaging application, yet is distorted by its off-site signal leakage. The endogenously activated DNA circuit could guarantee the specific and sensitive in vivo imaging utility yet was still unexplored. In this work, we engineered an endogenously and sequentially activated DNA circuit by using the specific enzymatic regulation strategy. This smart DNA circuit is consisting of two successive reaction modules, the initial site-specific circuitry exposure module and the subsequent circuitry activation module for amplified in vivo biosensing. Initially, the catalytic circuitry reactant was caged with a long elongated duplex, encoding with high energy barriers of circuitry crosstalk, to prevent the undesirable off-target signal leakage prior to its arrival in targeting cells. Subsequently, the as-integrated functional duplex could be specifically cleaved and removed by the endogenously overexpressed DNA excision repairing enzyme of cancer cells, thus liberating the DNA circuitry reactant for participating the catalyzed and amplified imaging of intracellular analyte, e.g. , microRNA. Meanwhile, the catalytic DNA circuit stayed inert in normal cells for lacking the indispensable cell-specific exposure of circuitry reactant. Through the sequential circuitry exposure (by endogenous enzyme of specific cells) and activation (by target of interest) procedure, our multiply guaranteed DNA circuit realized the robust in vivo imaging of tumor cells with high precision and reliability, thus supplementing a powerful toolbox for cancer diagnosis and treatment. [Display omitted] • An endogenously activated DNA circuit enables the intracellular imaging of miRNA through the enzyme-modulated methodology. • This system acquires the high-contrast imaging of miRNA in live mice by preventing the annoying off-site signal leakage. • The enzyme-regulation of DNA circuit facilitates the efficient and site-specific circuitry activation in specific live cells. • This work provided a simple yet powerful strategy to regulate various DNA circuits with biologically important functions. [ABSTRACT FROM AUTHOR]

The information encoded in the base sequence of DNA provides substantial structural and functional information for the instructive self-assembly of one-dimensional (1D) functional DNA nanostructures. The hybridization chain reaction (HCR) and the formation of HCR-stimulated DNAzyme nanochains are presented, as a means to develop amplified DNA sensors and aptasensors. Similarly, the rolling circle amplification (RCA) process is implemented to generate 1D DNA nanochains consisting of constant repeat units being implemented for the amplified sensing (using DNAzymes as repeat units) and for the switchable control of electron transfer at electrodes. 1D DNA nanostructures are used as templates for the programmed positioning of enzymes that enable the activation of enzyme cascades and the biocatalytic growth of metallic nanowires. The future perspectives of the self-assembly mechanisms are discussed. [ABSTRACT FROM AUTHOR]

Abstract: The present paper is the first report on an enzymatic logic gates system based on oxygen-controlled biofuel cell (BFC). By accepting dual gas-input signals and resulting in the maximum power output changes of the compartmentless BFC with bioanode/biocathode-immobilized enzymes, such system permits AND and XNOR Boolean logic gates readily achieved, reset and interconverted into each other in “one pot”. On the basis of the built-in Boolean XNOR logic, the proof-of-concept oxygen-controlled biocomputing system with miniature BFC operating in serum enabled us to construct a potential self-powered and implantable medical system with the diagnosis aim, which could intellectually make logic decisions that whether the dissolved oxygen content in body fluid is within normal limits or not. [Copyright &y& Elsevier]

Abstract: A method to fabricate AuAg bimetallic nanoparticles film by H2O2-mediated reduction of silver was reported. Gold nanoparticles (Au NPs) were first adsorbed onto the surface of a self-assembled 2-aminoethanethiol monolayer-modified gold film or 3-aminopropyltriethoxysilane (APTES) monolayer-modified quartz slide. Upon further treatment of this modified film with the solution containing silver nitrate (AgNO3) and H2O2, silver was deposited on the surface of Au NPs. The size of the AuAg bimetallic particles could be readily tuned by manipulating the concentration of H2O2. Surface plasmon resonance (SPR) was used to investigate the process, the deposition of silver on Au NPs modified gold film resulted in an obvious decrease of depth in the SPR reflectance intensity and minimum angle curves (SPR R-θ curves), which may be utilized for the quantitative SPR detection of the analyte, H2O2. Combination of the biocatalytic reaction that could yield H2O2 by using the enzyme, glucose oxidase, with the deposition of silver may enable the design of a glucose biosensor by SPR technique. Furthermore, we evaluated the AuAg bimetallic nanoparticles film for their ability to be an effective substrate for surface-enhanced Raman scattering (SERS). [Copyright &y& Elsevier]

Abstract: This paper reports the study of protein conformational change by Au nanoparticles (AuNPs)-amplified surface plasmon resonance (SPR) spectroscopy. Taking cytochrome c (Cyt c) as an example, this paper gives a detailed description of the construction of metal–protein–metal sandwich nanostructure consisting of an Au film underlayer, a cytochrome c intermediate layer and an AuNPs upper layer. The incorporation of AuNPs into SPR biosensing results in increased SPR sensitivity to protein conformational change as demonstrated by acid denaturation of Cyt c. It suggests the conformational change of surface-confined Cyt c leads to the distance and electromagnetic coupling variations of Au film–AuNPs. The constructed Au film–Cyt c–AuNPs sandwich is stable to repeat acid treatment using solutions in the pH range of 2.0–10.0 and yields reproducible measurements. With high sensitivity and stability, nanoparticle-amplified SPR spectroscopy can be used as a supplement method to protein conformational study. It has potential for developing novel sensors and/or switching devices in response to protein conformational change. [Copyright &y& Elsevier]

Abstract: We described the use of silica nanoparticles as building blocks for the immobilization of electrogenerated chemiluminescence (ECL) reagent Ru(bpy)3 2+ and the fabrication of layer-by-layer assembly film by alternating the deposition of the Ru(bpy)3 2+-doped silica nanoparticles and Au nanoparticles. UV–vis absorption spectroscopy, scanning electron microscopy (SEM), cyclic voltammetry and ECL were used to characterize the uniform growth of the multilayer film. Since Ru(bpy)3 2+ could still maintain its ECL property when doped into the silica nanoparticles, the as-prepared multilayer film could be used as an effective ECL sensor, and the sensor showed high sensitivity and good stability. [Copyright &y& Elsevier]

Abstract: In this paper, electrochemical surface plasmon resonance (SPR) method was first used to detect enzymatic reaction in bilayer lipid membrane (BLM) based on immobilizing horseradish peroxidase (HRP) in the BLMs supported by the redox polyaniline (PAn) film. By SPR kinetic curve in situ monitoring the redox transformation of PAn film resulted from the reaction between HRP and PAn, the enzymatic reaction of HRP with H2O2 was successfully analyzed by electrochemical SPR spectroscopy. The results show that this BLM supported on PAn film cannot only preserve the bioactivity of HRP immobilized in the membrane, but also provide a channel for the transfer of electrons between HRP and PAn on electrode surface. These characteristics enabled the development of SPR biosensor for sensitively detecting H2O2. H2O2 has been detected by electrochemical SPR spectroscopy in the concentration range of 5×10−5 M to 2×10−3 M. After each of detections, the SPR sensor surface was completely regenerated by electrochemically reducing the oxidized PAn to its reduced state. This method provides a novel route for enhancing the detection of small ligand of enzymatic reaction in BLM by electrochemical SPR spectroscopy. [Copyright &y& Elsevier]

Abstract: Through electrostatic layer-by-layer (LbL) assembly, negatively charged calf thymus double stranded DNA (CTds-DNA), and positively charged Zr4+ ions were alternately deposited on gold substrate modified with chemisorbed cysteamine. Thus-prepared three-dimensional DNA networks were characterized by surface plasmon resonance (SPR) spectroscopy, X-ray photoelectron spectroscopy (XPS) and infrared reflection–absorption spectroscopy (IR-RAS). SPR spectroscopy indicates that the effective thickness of DNA monolayer in the (DNA/Zr4+)1 bilayer was 1.5±0.1nm, which corresponds to the surface coverage of 79% of its full packed monolayer. At the same time, a linear increase of film thickness with increasing number of layers was also confirmed by SPR characterizations. The data of XPS and IR-RAS show that Zr4+ ions interact with both the phosphate groups and nitrogenous bases of DNA and load into the framework of DNA. Furthermore, the interactions between this composite film and heme protein cytochrome c (Cyt c) were investigated by SPR spectroscopy and electrochemistry. Compared with the adsorption of Cyt c on DNA monolayer, this composite multilayer film can obviously enhance the amount of immobilized Cyt c confirmed by SPR reflectivity-incident angle (R-θ) curves. Cyclic voltammetry (CV) indicates the Cyt c adsorbed on the composite film is electroactive, and the enhancement of peak current in CV indirectly verifies the increase of the amount of immobilized Cyt c. [Copyright &y& Elsevier]

Pb(Nd x Zr 0.52 Ti 0.48 )O 3 (PNZT) (x = 0%, 1%, 2%, 3%, 4%, 5%) thin films were prepared by sol-gel process to investigate the effects of neodymium substitution on crystalline orientation, microstructure and electric properties of lead zirconate titanate (PZT) films. X-ray diffraction (XRD) and scanning electron microscope (SEM) analysis showed that PNZT films with Nd doping concentration below 3% exhibited dense perovskite structure with (100) preferred orientation. The average grain size of PNZT films decreased as the Nd substitution increased. The maximum dielectric constant, remnant polarization and minimum coercive field were obtained in 2% Nd-doped PZT films. Fatigue resistance was also improved significantly with 2% Nd dopant. [ABSTRACT FROM AUTHOR]

It is meaningful to automatically learn the valuable features from the raw vibration data and provide accurate fault diagnosis results. In this paper, an enhancement deep feature fusion method is developed for rotating machinery fault diagnosis. Firstly, a new deep auto-encoder is constructed with denoising auto-encoder (DAE) and contractive auto-encoder (CAE) for the enhancement of feature learning ability. Secondly, locality preserving projection (LPP) is adopted to fuse the deep features to further improve the quality of the learned features. Finally, the fusion deep features are fed into softmax to train the intelligent diagnosis model. The developed method is applied to the fault diagnosis of rotor and bearing. The results confirm that the proposed method is more effective and robust compared with the existing methods. [ABSTRACT FROM AUTHOR]

Abstract: Myxoma virus (MV) is a highly lethal, rabbit-specific poxvirus that induces a disease called myxomatosis in European rabbits. In an effort to understand the function of predicted immunomodulatory genes we have deleted various viral genes from MV and tested the ability of these knockout viruses to induce lethal myxomatosis. MV encodes a unique 15kD cytoplasmic protein (M130R) that is expressed late (12h post infection) during infection. M130R is a non-essential gene for MV replication in rabbit, monkey or human cell lines. Construction of a targeted gene knockout virus (vMyx130KO) and infection of susceptible rabbits demonstrate that the M130R knockout virus is attenuated and that loss of M130R expression allows the rabbit host immune system to effectively respond to and control the lethal effects of MV. M130R expression is a bona fide poxviral virulence factor necessary for full and lethal development of myxomatosis. [Copyright &y& Elsevier]

Anoectochilus roxburghii is a traditional herb in China that can be potentially used to treat diabetes. A novel polysaccharide ARLP-W was isolated from Anoectochilus roxburghii by chromatography on DEAE-52 cellulose. Chemical analysis indicated that ARLP-W (8.1 × 104 Da) was mainly composed of mannose and glucose. The main linkages of glycosidic bonds of ARLP-W were β-1, 4-Manp and α-1, 4-Glcp. The terminal Glcp was connected to Manp-via O-3. RT-qPCR and western blotting analysis showed that ARLP-W caused a significant reduction in the levels of the key gluconeogenesis enzymes phosphoenolpyruvate carboxykinase (PEPCK) and glucose 6-phosphatase (G6Pase) in the liver. The results of the insulin resistance tests indicated that ARLP-W increased glucose absorption. These results indicate that ARLP-W has a good therapeutic effect on type 2 diabetes and can assist with further development and application treatment of diabetes. • A new homogeneous polysaccharide ARLP-W was isolated from Anoectochilus roxburghii. • The structures of polysaccharide ARLP-W was investigated. • ARLP-W improves insulin resistance and serum indexes on high-fat diet and STZ-induced T2DM model. • ARLP-W inhibits the expression of key gluconeogenesis enzymes PEPCK and G6Pase. [ABSTRACT FROM AUTHOR]

Highlights • Fluorescent method for biosensing of Zn2+, pyrophosphate, and alkaline phosphatase activity. • Real-time detection based on assembly-induced fluorescence enhancement by gold nanoclusters or quantum dots. • Capable of screening enzyme inhibitor and analyzing biological samples. • Sensitive assay of alkaline phosphatase with a detection limit of 3.4 pM. Abstract Fluorescent nanoparticles exhibit unique optical properties for applications in imaging and sensing. Herein, the enhancement of luminescence emission from self-assembled nanoparticles including gold nanoclusters, cadmium sulphide and near-infrared silver selenide quantum dots are reported. Addition of zinc and pyrophosphate ions induces assembly and disassembly of the particle aggregates and the corresponding intensified and recovery of fluorescence intensity, respectively. The enhancement is due to assembly-enhanced emission of metal nanoclusters and passivation of the surface trap states of quantum dots. With the hydrolysis of pyrophosphate catalyzed by alkaline phosphatase, the released zinc ions from pyrophosphate-zinc ion complexes mediate nanoparticle assembly and lead to luminescence regeneration. The assembly-induced fluorescence enhancement can be applied for sensitive assay of alkaline phosphatase with a detection limit of 3.4 pM in a continuous and real-time way. This method is capable of screening enzyme inhibitor and analyzing biological samples. [ABSTRACT FROM AUTHOR]

Extracellular vesicles (EVs) have been emerged as versatile drug delivery vehicles due to their outstanding biocompatibility and long-term circulation, yet are constrained with low targeting property and inefficient loading capacity from post-synthetic passive EVs encapsulation. Herein, we report a simple and feasible in situ biosynthetic approach to encapsulate tumor-targeting folate (FA)-modified EVs with intracellularly produced protoporphyrin X (PpIX) and doxorubicin (DOX). As compared with the traditional directly drug-incubated or drug-electroporated EVs, these biosynthesized EVs revealed high drug-loading efficiency with minimized structural and functional perturbations. Our multifunctional EVs revealed the enhanced accumulation and penetration into deep tumor parenchyma, as well as the strengthened immune response to ablate orthotopic and metastatic tumors, thus realizing the more reliable photochemotherapy. As an intelligent multi-mode therapeutic system, our biosynthetic EVs could be engineered with more therapeutic agents and show great promise for biomedicine applications. [ABSTRACT FROM AUTHOR]

Polynucleotide kinase (PNK) plays a crucial role in phosphorylation-related DNA repair, while its real time tracking and monitoring is unexplored for limited sensitivity and robustness of current PNK sensing strategies in complex biological environment. Herein, we proposed a concatenated hybridization chain reaction (Con-HCR)-based PNK sensing platform for ultra-sensitive PNK assay and intracellular imaging. In the presence of PNK, the 5′-hydroxyl termini of hairpin H p was phosphorylated for λ exonuclease (λ Exo)-mediated DNA cleavage reaction. This leads to the generation of initiator I for stimulating the subsequent Con-HCR-motivated assembly of branched dsDNA nanostructures with tremendously amplified Förster resonance energy transfer (FRET) signal. Owing to the multiple-responsive recognitions of PNK/exonuclease and the dual amplification of Con-HCR, the proposed method realized the sensitive and selective PNK assay as well as the screening of PNK inhibitors. This FRET-based signal transduction provides a straightforward and accurate procedure for analyzing PNK from complex cell lysate. Furthermore, the robust feature of the present system enabled their extensive application in monitoring the varied expression levels of intracellular PNK in living cells. In view of these remarkable characters, our Con-HCR-mediated PNK sensing strategy shows more potential applications in clinical diagnosis and new drug discovery researches. A concatenated hybridization chain reaction (Con-HCR)-mediated polynucleotide kinase (PNK) sensing platform was successfully constructed for sensitively and selectively detecting PNK, for screening PNK inhibitors and for realizing intracellular PNK imaging. Image 1 • An isothermal autonomous cascaded hybridization chain reaction (Con-HCR) circuit is constructed with ultralow background. • The Con-HCR-mediated polynucleotide kinase (PNK) sensing platform exhibits high sensitivity and selectivity in cell lysates. • Our Con-HCR imaging system can track the varied expressions of intracellular PNK with high robustness and accuracy. [ABSTRACT FROM AUTHOR]