Enterovirus 71 2B Induces Cell Apoptosis by Directly Inducing the Conformational Activation of the Proapoptotic Protein Bax.

Unlabelled: To survive and replicate within a host, many viruses have evolved strategies that target crucial components within the apoptotic cascade, leading to either inhibition or induction of cell apoptosis. Enterovirus 71 (EV71) infections have been demonstrated to impact the mitochondrial apoptotic pathway and induce apoptosis in many cell lines. However, the detailed mechanism of EV71-induced apoptosis remains to be elucidated.

Synthesis of wheatear-like ZnO nanoarrays decorated with Ag nanoparticles and its improved SERS performance through hydrogenation.

Semiconductor/noble metal composite SERS substrates have been extensively studied due to their unique bifunctionality. In this work, wheatear-like ZnO nanoarrarys have been fabricated via a modified low-temperature solution method. The hierarchical nanostructures that are constructed by stacked nanoflakes and long whiskers of ZnO possess a substantial number of characteristic nano corners and edges, which are proved to be beneficial to deposit more Ag nanoparticles (NPs).

G-quadruplex DNA/protoporphyrin IX-based synergistic platform for targeted photodynamic cancer therapy.

Photodynamic therapy (PDT) is an emerging technique to induce cancer cell death. However, the tumor specificity, cellular uptake and biodistribution of many photosensitizers urgently need to be improved. In this regard, we show here that the integrated nanoassemblies based on G-quadruplex DNAs (GQDs)/protoporphyrin IX (PPIX) can serve as a synergistic platform for targeted high-performance PDT.

Alternative splicing at GYNNGY 5' splice sites: more noise, less regulation.

Numerous eukaryotic genes are alternatively spliced. Recently, deep transcriptome sequencing has skyrocketed proportion of alternatively spliced genes; over 95% human multi-exon genes are alternatively spliced. One fundamental question is: are all these alternative splicing (AS) events functional? To look into this issue, we studied the most common form of alternative 5' splice sites-GYNNGYs (Y = C/T), where both GYs can function as splice sites.

The initial stage of the dissociative adsorption and the surface electronic state evolution of NH3 on Si(111)-(7 × 7).

Adsorption of NH3 molecules on Si(111)-(7 × 7) has been studied by scanning tunneling microscopy. We find that the dissociative adsorption is site-selective and exhibits two adsorption structures resulting from different reaction channels: [Formula: see text] and [Formula: see text]. To explain the dissociation processes, an adsorption model for these reactions is given.

Superconducting pairing symmetry and energy gaps of the two-orbital t-t'-J-J' model: comparisons with the ARPES experiments in iron pnictides.

Motivated by the discovery of the iron-based superconductors, we present the theoretical results on the superconducting phase diagram, the temperature-dependent Fermi surface structures in normal state and the angle-resolved photoemission spectroscopy (ARPES) character of quasiparticles of the two-orbital t-t'-J-J' model. In the reasonable physical parameter region of LaFeAsO(1-x)F(x), we find the superconducting phase is stable, and the pairing symmetry is weakly anisotropic and nodeless d(x(2)-ηy(2))+S(x(2)y(2))-wave, qualitatively in agreement with the ARPES experiments in iron pnictide superconductors. Nevertheless, the two ratios of the energy gaps to T(c) deviate from the ARPES data, suggesting that a more elaborate theoretical model is needed.

Structure and magnetic properties of Fe-doped ZnO prepared by the sol-gel method.

Zn(0.97)Fe(0.03)O nanoparticles were synthesized by the sol-gel method.

Anharmonic effect on lattice distortion, orbital ordering and magnetic properties in Cs(2)AgF(4).

We develop the cluster self-consistent field method incorporating both electronic and lattice degrees of freedom to study the origin of ferromagnetism in Cs(2)AgF(4). After self-consistently determining the harmonic and anharmonic Jahn-Teller distortions, we show that the anharmonic distortion stabilizes the staggered x(2)-z(2)/y(2)-z(2) orbital and ferromagnetic ground state, rather than the antiferromagnetic one. The amplitudes of lattice distortions, Q(2) and Q(3), the magnetic coupling strengths, J(x,y), and the magnetic moment are in good agreement with the experimental observations.

Synthesis and characterization of a new trifunctional magnetic-photoluminescent-oxygen-sensing nanomaterial.

Magnetic Fe(2)O(3) nanoparticles coated with SiO(2) chemically doped with a Ru(II) complex were prepared using a simple solution based method. Field-emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM) showed that the Fe(2)O(3) nanoparticles with a mean diameter of ∼115 nm were successfully coated with Ru(II) complex-chemically doped SiO(2) shell with a thickness of ∼30 nm. The obtained nanocomposite material showed a strong magnetic response to a varying magnetic field, exhibited the bright red triplet metal-to-ligand charge transfer ((3)MLCT) emission, and its photoluminescent intensity was sensitive to oxygen concentration.

Mesoporous magnetic hollow nanoparticles-protein carriers for lysosome escaping and cytosolic delivery.

It is important for a controlled release system to determine whether nanoparticles can penetrate cell membranes and deliver protein into the nuclear or cytosolic compartments of cells, and thus function as carriers. Here, we prepared different functionalized mesoporous magnetic hollow nanoparticles (MMHs) and chose bovine serum albumin (BSA) as a model protein to detect the intracellular trafficking of MMHs. The results showed that MMHs modified with amino groups (AMMHs) were efficient in protein loading and that the loading was dependent on the pH, temperature and ionic strength.

Controlled synthesis of pentagonal gold nanotubes at room temperature.

Large quantities of pentagonal gold nanotubes have been synthesized by reducing chloroauric acid with silver nanowires in an aqueous solution of hexadecyltrimethylammonium bromide (CTAB) at room temperature. These gold nanotubes possess perfect structures, smooth surfaces, highly crystalline walls, and similar cross-sections to that of the silver template. In this process, the CTAB participation was found to be crucial for shape-controlled synthesis of pentagonal gold nanotubes.

The transformation of single-crystal calcium phosphate ribbon-like fibres to hydroxyapatite spheres assembled from nanorods.

Two precursors of ribbon-like anhydrous dicalcium phosphate (DCPA) and calcium phosphate fibres were successfully synthesized at 85 °C through a simple and mild pathway from Ca(NO(3))(2)·4H(2)O and (NH(4))(2)HPO(4) upon the hydrolysis of urea. Different molar concentrations of urea resulted in different precursors, including precursor I (DCPA phase) and precursor II (calcium phosphate with DCPA, octacalcium phosphate (OCP) and hydroxyapatite (HAp) phase). By immersing the two precursors in ammonium hydroxide solution (pH = 12), the transformation from precursors to hydroxyapatite could be achieved.

Water permeation across nanochannels with defects.

Defects are common in fabricated nanochannels. In this paper, water permeation across a single-walled carbon nanotube with defects was studied using molecular dynamics simulations. It is found that the impact on water permeation is negligible when the density of the defects is small, while a significant reduction in water permeation is observed when the density of the defects is high.

DNAzyme-based colorimetric sensing of lead (Pb(2+)) using unmodified gold nanoparticle probes.

Novel functional oligonucleotides, especially DNAzymes with RNA-cleavage activity, have been intensively studied due to their potential applications in therapeutics and sensors. Taking advantage of the high specificity of 17E DNAzyme for Pb(2+), highly sensitive and selective fluorescent, electrochemical and colorimetric sensors have been developed for Pb(2+). In this work, we report a simple, sensitive and label-free 17E DNAzyme-based sensor for Pb(2+) detection using unmodified gold nanoparticles (GNPs) based on the fact that unfolded single-stranded DNA could be adsorbed on the citrate protected GNPs while double-stranded DNA could not.

Two- and three-dimensional micro/nanostructure patterning of CdS-polymer nanocomposites with a laser interference technique and in situ synthesis.

Two- and three-dimensional (2D and 3D) micro/nanostructures of CdS-polymer nanocomposites have been successfully patterned, combining photopolymerization via a laser four-beam interference technique with in situ synthesis of CdS nanoparticles in the patterned polymer matrix. The morphology and optical properties of CdS nanoparticles in polymer matrices have been confirmed using TEM, XRD, FTIR, UV-vis absorption and fluorescence spectroscopy. Laser irradiation time and film thickness are certified to be the key factors for the control of the micro/nanostructures.

Fabrication and in vitro biomineralization of bioactive glass (BG) nanofibres.

Bioactive glass nanofibres have excellent bioactivity and cell compatibility, and are regarded as a promising next-generation biomaterial in the bone-regeneration field. This paper is concentrated on the effect of electrospinning parameters on the diameter and morphology of bioactive glass nanofibres, and the process of in vitro biomineralization. In this work, sol-gel glass nanofibres with high bioactivity were prepared by electrospinning processing in the presence of poly(vinyl pyrrolidone) (PVP) and pluronic P123 (EO(20)-PO(70)-EO(20)) as chain entanglements.

Biofunctionalization of CeF(3):Tb(3+) nanoparticles.

CeF(3):Tb(3+) nanoparticles (short pillar-like morphology with an average length and width of 11 and 5 nm, respectively) were successfully prepared by a polyol process using diethyleneglycol (DEG) as solvent. After being functionalized with a SiO(2)-NH(2) layer, these CeF(3):Tb(3+) nanoparticles can be conjugated with biotin molecules (activated by thionyl chloride) and further with avidin. The as-formed CeF(3):Tb(3+) nanoparticles, CeF(3):Tb(3+) nanoparticles functionalized with amino groups, biotin conjugated amino-functionalized CeF(3):Tb(3+) nanoparticles and biotinylated CeF(3):Tb(3+) nanoparticles bonded with avidin were characterized by x-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR), UV/vis absorption spectra and luminescence spectra, respectively.

Dependence of the cytotoxicity of multi-walled carbon nanotubes on the culture medium.

This study examined the influence of multi-walled carbon nanotubes (MWNTs) on the growth of the unicellular protozoan Tetrahymena pyriformis. Contrary to the findings from most other investigations, our experiment indicated that MWNTs stimulated growth of the cells cultured in proteose peptone yeast extract medium (PPY). Atomic force microscopy images and thermogravimetric analysis showed the spontaneous formation of peptone-MWNT conjugates in the medium by noncovalent binding.

Fabrication of a nanocrystalline Ni-Co/CoO functionally graded layer with excellent electrochemical corrosion and tribological performance.

Nanocrystalline (NC) Ni-Co/CoO functionally graded materials with excellent lubricating, high anti-corrosion and anti-wear performance were fabricated by electrodeposition and subsequent cyclic thermal oxidation and quenching. Transmission electron microscopy and energy dispersive x-ray spectroscopy investigations show that bulk Ni-Co gradient deposits with an average grain size in the range of 13-40 nm demonstrated a graded structure transition from face-centred cubic to hexagonal close packed and graded composition changes from Ni-rich to Co-rich regions with the increase in deposit thickness. X-ray diffraction and x-ray photoelectron spectroscopy analysis indicated the surface layer of NC Ni-Co graded materials to be mainly composed of dense and ultrafine CoO with a (111) preferred orientation.

Facile sonochemical synthesis of CePO(4):Tb/LaPO(4) core/shell nanorods with highly improved photoluminescent properties.

A simple, efficient and quick method has been established for the synthesis of CePO(4):Tb nanorods and CePO(4):Tb/LaPO(4) core/shell nanorods via ultrasound irradiation of inorganic salt aqueous solution under ambient conditions for 2 h. The as-prepared products were characterized by means of powder x-ray diffraction (PXRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED), x-ray photoelectron spectroscopy (XPS), photoluminescence (PL) spectra and lifetimes. TEM micrographs show that all of the as-prepared cerium phosphate products have rod-like shape, and have a relatively high degree of crystallinity and uniformity.

The effects of gamma-irradiation dose on chemical modification of multi-walled carbon nanotubes.

Multi-walled carbon nanotubes (MWNTs) irradiated with gamma-rays were subjected to chemical modification with thionyl chloride and decylamine. Products from chemical treatment were characterized by both FTIR and Raman spectra. Element analysis (EA) and thermogravimetric analysis (TGA) for the modified soluble MWNTs (s-MWNTs) indicated that gamma-radiation increased the concentration of functional groups bound to MWNTs, which arose due to the increasing number of defect sites created on the MWNTs by gamma-photons.

Stabilized and size-tunable gold nanoparticles formed in a quaternary ammonium-based room-temperature ionic liquid under gamma-irradiation.

Colloidal gold nanoparticles were synthesized in a quaternary ammonium-based room-temperature ionic liquid (QAIL) by gamma-radiation for the first time. Transmission electron microscopy, x-ray diffraction and optical techniques were used to characterize the colloidal nanoparticles. By changing the experimental conditions, the size of the gold nanoparticles can be varied between 10 and 50 nm.

Well-ordered end-to-end linkage of gold nanorods.

In this study, it is found that as-prepared gold nanorods can be linked to each other in an end-to-end way by using cysteine as a molecular bridge. Both transmission electron microscopy and UV-visible optical spectroscopy demonstrated the uniaxial assembly of the gold nanorods. The controlled addition of cysteine into the gold nanorod solution resulted in their preferential binding to the two ends of the gold nanorods.