Immunogenic Cell Death of Breast Cancer Stem Cells Induced by an Endoplasmic Reticulum-Targeting Copper(II) Complex

Immunogenic cell death (ICD) offers a method of stimulating the immune system to attack and remove cancer cells. We report a copper(II) complex containing a Schiff base ligand and a polypyridyl ligand, 4 , capable of inducing ICD in breast cancer stem cells (CSCs). Complex 4 kills both bulk breast cancer cells and breast CSCs at sub-micromolar concentrations. Notably, 4 exhibits greater potency (one order of magnitude) towards breast CSCs than salinomycin (an established breast CSC-potent agent) and cisplatin (a clinically approved anticancer drug). Epithelial spheroid studies show that 4 is able to selectively inhibit breast CSC-enriched HMLER-shEcad spheroid formation and viability over non-tumorigenic breast MCF10 A spheroids. Mechanistic studies show that 4 operates as a Type II ICD inducer. Specifically, 4 readily enters the endoplasmic reticulum (ER) of breast CSCs, elevates intracellular reactive oxygen species (ROS) levels, induces ER stress, evokes damage-associated molecular patterns (DAMPs), and promotes breast CSC phagocytosis by macrophages. As far as we are aware, 4 is the first metal complex to induce ICD in breast CSCs and promote their engulfment by immune cells.     

Synthesis method of novel Gd2O3@Fe3O4 nanocomposite modified by dextrose capping agent

In current study, gadolinium oxide was heterogeneously formed on the surface of iron oxide nanoparticles and further modified with dextrose capping agent to be used in biomedical applications, especially for contrast enhancement in MR images. First, two types of iron oxide nanoparticles were prepared at 25 and 80 ^°C via simple coprecipitaion method. Then, gadolinium oxide nanoparticles were synthesized through a consecutive precipitation process on previously formed iron oxide seeds in an aqueous media and subsequent annealing at 300 ^°C. Finally, dextrose was used as capping agent to stabilize nanocomposites in a colloidal suspension. X-ray diffraction (XRD), Scanning and Transmission electron microscopy, Dynamic Laser Scattering (DLS), Fourier-Transform Infrared Spectroscopy (FTIR), and Magnetometery (VSM) techniques were employed for nanocomposites investigation and MTT-assay method used for viability assessment of colloidal samples. Measurements based on Scherrer equation from XRD patterns showed that increasing coprecipitation temperature resulted bigger iron oxide crystallites. The iron oxide crystallite size was increased from 15.1 to 28.1 nm. Precipitation process led to gadolinium oxide formation with 30.7 and 38.8 nm crystallite sizes, respectively. TEM images revealed that iron oxide agglomerates were encapsulated in gadolinium oxide surroundings. Hydrodynamic size of the coated nanoparticles with dextrose was 208 and 247 nm. In VSM examinations, nanocomposites did not display coercive field and the saturation magnetization was 1.93 emu/g. MTT-assay results showed 80% viability in 285 μg nanocomposites containing 96.9 μg [Fe] and 11.4 μg [Gd].     

多级孔HZSM-5分子筛催化快速热解生物质制芳烃

采用酸和/或碱处理法制备了一系列多级孔HZSM-5分子筛,采用XRD、N2吸附、XRF、TEM、27Al MAS NMR和NH3-TPD等表征手段对其孔道结构和酸性进行表征。表征结果表明,采用碱处理方法,可获得孔径集中于3～6 nm的介孔结构,通过改变酸、碱处理次序,可调变酸中心数量和强酸/总酸中心比例。在Py-GC/MS装置上,以纤维素和水稻秸秆为原料,研究多级孔分子筛结构对催化快速热解(CFP)制芳烃反应的影响。反应评价结果表明,同商品级HZSM-5相比,采用先碱后酸处理获得的多级孔HZSM-5分子筛(HZ-OH/H),可将纤维素CFP芳烃碳产率由32.3%提高至43.6%,可将水稻秸秆CFP芳烃碳产率由23.0%提高至30.8%。多级孔HZ-OH/H分子筛的孔道结构和酸中心分布特征,对开发应用于生物质制芳烃的高效工业催化剂具有借鉴意义。     

Activation of graphene aerogel with phosphoric acid for enhanced electrocapacitive performance

We present a facile and efficient route to introduce in-plane nanopores on the graphene sheets by activation of graphene aerogel (GA) with phosphoric acid (H₃PO₄). Results from N₂ adsorption and TEM images showed that H₃PO₄ activation created mesopores with pore size of 2–8 nm on the graphene sheets. With such nanopores on graphene sheets, the activated GA exhibits a specific capacitance of 204 F g⁻¹, enhanced rate capability (69% capacitance retention from 0.2 to 30 A g⁻¹), reduced equivalent series resistance (3.8 mΩ) and shortened time constant (0.73 s) when comparing with the hydrothermally-derived pristine GA and thermally annealed GA in the absent of H₃PO₄. The excellent capacitive properties demonstrate that introduction of nanopores on GA by H₃PO₄ activation not only provides large ion-accessible surface area for efficient charge storage, but also promotes the kinetics of electrolyte across the graphene two-dimensional planes.     

Facile solid-state synthesis of Ag/graphene oxide nanocomposites as highly active and stable catalyst for the reduction of 4-nitrophenol

A facile solid-state synthetic route was used to fabricate graphene oxide (GO) decorated with Ag nanoparticles. Ag/GO nanocomposites were prepared by reducing silver acetate with ascorbic acid in the presence of GO at ambient conditions. The characterization results showed that Ag nanoparticles with an average diameter of ~ 50 nm were well dispersed on the surface of GO nanosheets. Moreover, an application of the obtained Ag/GO nanocomposites as a catalyst in the reduction of 4-nitrophenol (4-NP) to 4-aminophenol by NaBH₄ was demonstrated. The Ag/GO nanocomposites exhibited high activity and stability for the catalytic reduction of 4-NP.     

Effect of auxiliary blowing agents on properties of rigid polyurethane foams based on liquefied products from peanut shell

The bio‐based rigid polyurethane (PU) foams were successfully prepared based on liquefied products from peanut shell with water as the blowing agent. The influence of reaction parameters on properties of rigid PU foams was investigated. Rigid PU foams showed excellent compressive strength and low shrinkage ratio, whereas their open‐cell ratio and water absorption were higher. Therefore, rigid PU foams were synthesized with petroleum ether, diethyl ether, and acetone as auxiliary blowing agents and their inner temperature, shrinkage performance, density, compressive strength, water absorption, and open‐cell ratio were determined. The results indicated that above rigid PU foams showed lower compressive strength than the original foam but their water absorption and close‐cell ratio were improved. Compared with the original foam, the highest inner temperature of rigid PU foams with petroleum ether, diethyl ether, and acetone as auxiliary blowing agents was reduced by 11, 19, and 23 °C, respectively. Typically, foams with petroleum ether as auxiliary blowing agent displayed better water absorption and swelling ratio in water and exhibited obvious improvement in close‐cell ratio. These foams were preferable for application in thermal insulation materials because of low thermal conductivity and better corrosion resistance. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45582.     

Effect of Nb2O5 content and sintering temperature on the microstructure and bending strength of porous Ni-YSZ cermets

Porous Ni-YSZ cermets are prepared by reducing NiO-YSZ composites upon exposure to (Ar+6% H₂) gas. The porous cermets are prepared by the addition of carbon black (0.123 mol) to mixed NiO-YSZ powders and the conversion of NiO to Ni in the NiO-YSZ composites. The microstructure and bending strength of porous Ni-YSZ cermets as functions of sintering temperature and Nb₂O₅ content are discussed. The Ni-YSZ cermets consist of uniformly distributed Ni and YSZ grains as well as pores. Both higher sintering temperature and higher Nb₂O₅ content yield lower porosity, thus increasing the bending strength. The bending strength of 0.00470 mol% Nb₂O₅–containing Ni-YSZ cermets sintered at 1400 °C (111 MPa) is about two times higher than that of Nb₂O₅–free Ni-YSZ cermets sintered at 1400 °C (59 MPa).     

Cost-effective large-scale synthesis of oxygen-defective ZnO photocatalyst with superior activities under UV and visible light

A cost-effective solution method was developed to produce ZnO photocatalyst in large quantity, through the conversion of ε-Zn(OH)₂ to ZnO in NaOH solutions. Experimental results indicated that the concentrated NaOH solution (4 mol L⁻¹) promoted the rapid formation of ZnO owing to the enhanced dissolution-precipitation reactions. The large-scale synthesis was also achieved with high-yield and solvent-recyclability. Structural analysis based on X-ray photoelectron spectroscopy, electron spin resonance and photoluminescence revealed that the as-prepared ZnO photocatalyst was rich in oxygen vacancies (V_O). The V_O-rich ZnO photocatalyst exhibited improved visible-light absorption, higher photocurrent responses and superior activities toward the degradation of rhodamine B under both UV (λ~254 nm) and visible-light illumination (λ>420 nm) compared to commercial ZnO and P25 TiO₂ powders, as well as good cycle stability. Based on the results of photoluminescence and active species detection, the V_O-enhanced photocatalytic activity was attributed to the generation of V_O-isolated level in the band structure. Under UV light, the V_O-level could promote charge separation by trapping the photoinduced electrons, while under visible-light, the V_O-level improved visible-light absorption and facilitated the charge generation. The presently developed synthesis may potentially benefit the large-scale production and low-cost application of ZnO photocatalyst for solar energy utilization.     

Aluminum titanate based ceramics from aluminum sludge waste

This work aims at obtaining aluminum titanate-based ceramics (Al₂TiO₅: AT) composites from industrial wastes. Al-sludge waste and rutile ore were used as rich sources of alumina and titania instead of pure materials. Sludge-(0–40 wt%) rutile mixtures were mixed, formed and fired at 1350 °C for various times. Phase composition, microstructure, densification, mechanical and thermal behaviors of the obtained AT composites have been investigated. Complete conversion of the starting materials to AT with bulk density of 3.199 g/cm³, compressive strength and modulus of rupture of 326.425 MPa and 30.84 MPa, respectively and very low CTE (−0.927*10⁻⁶ K⁻¹) were achieved by firing the sludge-(30 wt%) rutile at 1350 °C for 4 h. These results suggest that the obtained AT-ceramics from Al-sludge waste-rutile ore are a promising and an ecofriendly route.