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Glioblastoma multiforme (GBM) is an aggressive brain cancer with a poor prognosis and few treatment options. Here, building on the observation of elevated lactate (LA) in resected GBM, we develop biomimetic therapeutic nanoparticles (NPs) that deliver agents for LA metabolism-based synergistic therapy. Because our self-assembling NPs are encapsulated in membranes derived from glioma cells, they readily penetrate the blood-brain barrier and target GBM through homotypic recognition. After reaching the tumors, lactate oxidase in the NPs converts LA into pyruvic acid (PA) and hydrogen peroxide (H2O2). The PA inhibits cancer cell growth by blocking histones expression and inducing cell-cycle arrest. In parallel, the H2O2 reacts with the delivered bis[2,4,5-trichloro-6-(pentyloxycarbonyl)phenyl] oxalate to release energy, which is used by the co-delivered photosensitizer chlorin e6 for the generation of cytotoxic singlet oxygen to kill glioma cells. Such a synergism ensures strong therapeutic effects against both glioma cell-line derived and patient-derived xenograft models. Targeting cancer-associated metabolism is evolving as a promising approach for cancer therapy. Here, the authors generate cancer cell-membrane encapsulated nanoparticles to induce cell cycle arrest and cytotoxicity in lactate-high cancer cells, reducing tumourigensis in glioblastoma cell-line and patient-derived models. [ABSTRACT FROM AUTHOR]

We have analyzed the effect of the final rolling temperature on the morphology, mechanical properties, carbide nanoparticle size, and dislocation density of Ti-Mo ferritic steel. The microstructure was mainly composed of equiaxed ferrite, ultrafine ferrite, and polygonal deformed ferrite, whose three proportions were affected significantly by the final rolling temperature. The change trend of the mechanical strength was in line with the dislocation density under different finishing rolling temperatures, whereas the ferrite grain size change trend was the opposite. There were various types of nanoparticle precipitation in the test steels: interphase precipitation, dispersion, dislocation precipitation, and deformation-induced precipitation. The optimum mechanical properties were obtained at a final rolling temperature of 900 °C. Quantitative analysis showed that the effect of the final rolling temperature on the yield strength was mainly because of dislocation and precipitation strengthening. The toughening mechanism is attributed to the fine grain strengthening of nanoparticles in austenite stage and the precipitation strengthening of ferrite stage. [ABSTRACT FROM AUTHOR]

Excess Bi2O3 was added to 0.94Bi0.5Na0.5TiO3-0.06BaTiO3 ceramic and the evolution of dielectric, electromechanical properties and electrocaloric effect (ECE) were studied. With increasing Bi2O3 addition, the nonergodic relaxor phase transformed to ergodic relaxor phase. The XRD patterns and Raman spectroscopy show the increasing relaxor properties with excess Bi2O3 doping. The Bi0.53Na0.5TiO3-BaTiO3 ceramic exhibited a temperature insensitive ECE with an "Λ" type, the variation of which was less than 26% over 30 ~ 120 °C. The temperature stability of ECE for Bi0.53Na0.5TiO3-BaTiO3 ceramic was related with the characteristics of ergodic relaxor phase, which was clarified by structural and Raman spectroscopy analysis. [ABSTRACT FROM AUTHOR]

AgBr microparticles decorated by CuO nanoparticles were prepared by a facile direct precipitation method. The composite exhibited enhanced visible-light-driven photocatalytic performance for methyl orange (MO) degradation, about 4.3 times that of pure AgBr. The phases of CuO and AgBr were demonstrated by X-ray diffraction analysis as well as XPS. The SEM images and the cycle experiment revealed that the stability of AgBr was improved significantly by combining with CuO during visible-light illumination. The pH values and the trapping experiments of active species provided good evidences that p-n heterojunction was formed. The high performance and stability of composite were attributed to the crucial role of inner field in p-CuO/n-AgBr, which may transfer holes out of AgBr. The charge transfer mechanism of CuO/AgBr was proposed and discussed in detail. [ABSTRACT FROM AUTHOR]

We investigated the efficacy and safety of ultrasound (US)-targeted microbubble (MB) destruction (UTMD)-enhanced delivery of monomethoxypoly(ethylene glycol)-poly(lactic-co-glycolic acid)-poly- l-lysine (mPEG-PLGA-PLL) nanoparticles (NPs) loading Cy3-labelled platelet-derived growth factor BB (PDGF-BB) siRNA to rat retina in vivo. Eighty Wistar rats were divided into five groups (G). The right eyes, respectively, received an intravitreal injection as follows: normal saline (NS) (G1), NPs and NS (G2), NPs and MBs (G3), NPs and NS (G4) and NPs and MBs (G5). In G4 and G5, the eyes were exposed to US for 5 mins. Twenty-four hours after transfection, the uptake and distribution of Cy3-labelled siRNA in rat retina were observed by fluorescent microscope. The percentage of Cy3-labelled siRNA-positive cells was evaluated by flow cytometer. The levels of PDGF-BB mRNA in retinal pigment epithelium (RPE) cells and secreted PDGF-BB proteins were also measured. Hematoxylin and eosin staining and frozen sections were used to observe tissue damage. Our results showed that the number of Cy3-labelled siRNA-positive cells in G5 was significantly higher than those of the other groups ( P<0.05 for all comparisons). The maximum efficiency of siRNA uptake in neural retina was 18.22±1.67%. In G4 and G5, a small number of Cy3-labelled siRNA-positive cells were also detected in the pigmented cell layer of the retina. NPs loading siRNA delivered with UTMD could more effectively down-regulate the mRNA and protein expression of PDGF-BB than NPs plus US ( P=0.014 and P=0.007, respectively). Histology showed no evident tissue damage after UTMD-mediated NPs loading siRNA transfection. UTMD could be used safely to enhance the delivery of mPEG-PLGA-PLL NPs loading siRNA into rat retina. [ABSTRACT FROM AUTHOR]

Patterned surfaces with special wettability and adhesion (sliding, sticky or patterned superoleophobic surface) can be found on many living creatures. They offer a versatile platform for microfluidic management and other biological functions. Inspired by their precise arrangement of structure and chemical component, we described a facile one-step approach to construct large scale pinecone-like anatase TiO2 particles (ATP) film. The as-prepared ATP film exhibits excellent superamphiphilic property in air, changes to underwater superoleophobicity with good dynamical stability. In addition, erasable and rewritable patterned superamphiphobic ATP films or three-dimensional (3D) Janus surfaces were constructed for a versatile platform for microfluidic management and biomedical applications. In a proof-of-concept study, robust super-antiwetting feet for artificial anti-oil strider at the oil/water interface, novel superamphiphobic surface for repeatable oil/water separation, and multifunctional patterned superamphiphobic ATP template for cell, fluorecent probe and inorganic nanoparticles site-selective immobilization were demonstrated. [ABSTRACT FROM AUTHOR]

FeO/CNTs nanocomposites, which were prepared by polyol-medium in situ high-temperature decomposition of Fe( acac) using PVP as stabilizing agent and modified with SDS, were further decorated with high-quality ZnS nanocrystal via a wet technique in glycol solution. The obtained ZnS/FeO/CNTs nanohybrids were characterized by XRD, FT-IR, Raman microscope, TEM, EDS, XPS, VSM and fluorophotometers. Results indicated that magnetic FeO nanoparticles and fluorescent ZnS nanocrystal were uniformly dispersed on the surface of CNTs layer-by-layer with PVP and SDS as stabilizing agent and ion-capture agent, respectively. The novel multi-functional nanohybrids exhibit super-paramagnetic properties with a saturation magnetization about 6·795 emu g at room temperature and show a strong emission band at 367 nm with a broad shoulder around 342-483 nm due to the interactions and/or background emissions of FeO and CNTs. The superparamagnetic and fluorescent properties of obtained products are promising for potential applications in magnetically guided and fluorescence tracing drug delivery systems. [ABSTRACT FROM AUTHOR]