Bottom-Up Construction of Mesoporous Cerium-Doped Titania with Stably Dispersed Pt Nanocluster for Efficient Hydrogen Evolution.

Hydrogen generation is one of the crucial technologies to realize sustainable energy development, and the design of advanced catalysts with efficient interfacial sites and fast mass transfer is significant for hydrogen evolution. Herein, an in situ coassembly strategy was proposed to engineer a cerium-doped ordered mesoporous titanium oxide (mpCe/TiO2), of which the abundant oxygen vacancies (Ov) and highly exposed active pore walls contribute to good stability of ultrasmall Pt nanoclusters (NCs, ∼ 1.0 nm in diameter) anchored in the uniform mesopores (ca. 20 nm). Consequently, the tailored mpCe/TiO2 with 0.5 mol % Ce-doping-supported Pt NCs (Pt-mpCe/TiO2-0.5) exhibits superior H2 evolution performance toward the water-gas shift reaction with a 0.73 molH2·s-1·molPt-1 H2 evolution rate at 200 °C, which is almost 6-fold higher than the Pt-mpTiO2 (0.13 molH2·s-1·molPt-1 H2). Density functional theory calculations confirm that the structure of Ce-doped TiO2 with Ce coordinated to six O atoms by substituting Ti atoms is thermodynamically favorable without the deformation of Ti-O bonds. The Ov generated by the six O atom-coordinated Ce doping is highly active for H2O dissociation with an energy barrier of 2.18 eV, which is obviously lower than the 2.37 eV for the control TiO2. In comparison with TiO2, the resultant Ce/TiO2 support acts as a superior electron acceptor for Pt NCs and causes electron deficiency at the Pt/support interface with a 0.17 eV downshift of the Pt d-band center, showing extremely obvious electronic metal-support interaction (EMSI). As a result, abundant and hyperactive Ti3+-Ov(-Ce3+)-Ptδ+ interfacial sites are formed to significantly promote the generation of CO2 and H2 evolution. In addition, the stronger EMSI between Pt NCs and mpCe/TiO2-0.5 than that between Pt and mpTiO2 contributes to the superior self-enhanced catalytic performance during the cyclic test, where the CO conversion at 200 °C increases from 72% for the fresh catalyst to 99% for the used one. These findings reveal the subtle relationship between the mesoporous metal oxide-metal composite catalysts with unique chemical microenvironments and their catalytic performance, which is expected to inspire the design of efficient heterogeneous catalysts.

Preparation of Solid Dispersion of Polygonum Cuspidatum Extract by Hot Melt Extrusion to Enhance Oral Bioavailability of Resveratrol.

The aim of this study was to improve the solubility, bioavailability, and stability of resveratrol (RES-SD) Solid Dispersion in Polygonum cuspidatum extract (PCE) by hot melt extrusion (HME). In addition, the role of the auxiliary substances in PCE was also studied. The solid dispersion of Polygonum cuspidatum extract was prepared by hot-melt extrusion. The optimum formula was selected by single factor design and orthogonal test. The optimum formula was barrel temperature 140 °C, screw rotation speed 40 rpm/min, and the ratio of Polygonum cuspidatum extract to HPMCAS was 1:2. The dissolution test showed that PCE-SD increased the dissolution of RES from 46.75 ± 0.47% to 130.06 ± 0.12%. The pharmacokinetics curve of rats showed that PCE-SD increased AUC0-t of RES from 111,471.22 ± 11.4% to 160,458.968 ± 15.7%, indicating an approximately 1.44-fold increase in absorption. In addition, the rotation speed of PCE-SD screw is less than that of RES-SD screw. The bioavailability of PCE-SD was slightly better than that of RES-SD. PCE-SD is more hygroscopic than RES-SD. PCE-SD increased the solubility and oral bioavailability of RES. The auxiliary substances in Polygonum cuspidatum extract have influence on its preparation technology, stability, and bioavailability.

Dietary Nutritional Level Affects Intestinal Microbiota and Health of Goats.

The intestine is a complex micro-ecosystem, and its stability determines the health of animals. Different dietary nutritional levels affect the intestinal microbiota and health. In this study, the nutritional levels of energy and protein in the diet of goats were changed, and the body weight was measured every 15 days. In the late feeding period, 16 S rRNA sequencing technology was used to detect the content of microorganisms. A meteorological chromatograph was used to detect volatile fatty acids in the cecum and colon of goats. In the feeding stage, reducing the nutritional level of the diet significantly reduced the weight of the lamb (p < 0.05). In the cecum, the abundance of potentially harmful bacteria, such as Sphingomonas, Marvinbryantia, and Eisenbergiella, were significantly enriched in goats fed with the standard nutritional level diets (p < 0.05). Additionally, the contents of acetate (p = 0.037) and total VFAs (p = 0.041) increased. In the colon, the abundance of SCFAs-producing bacteria, such as Ruminococcaceae, Christensenellaceae, and Papillibacter, decreased as the nutritional level in the diet increased (p < 0.05). In conclusion, the increase in nutritional level could affect the growth performance and composition of intestinal microbiota.

Ordered Mesopore Confined Pt Nanoclusters Enable Unusual Self-Enhancing Catalysis.

As an important kind of emerging heterogeneous catalyst for sustainable chemical processes, supported metal cluster (SMC) catalysts have received great attention for their outstanding activity; however, the easy aggregation of metal clusters due to their migration along the substrate's surface usually deteriorates their activity and even causes catalyst failure during cycling. Herein, stable Pt nanoclusters (NCs, ∼1.06 nm) are homogeneously confined in the uniform spherical mesopores of mesoporous titania (mpTiO2) by the interaction between Pt NCs and metal oxide pore walls made of polycrystalline anatase TiO2. The obtained Pt-mpTiO2 exhibits excellent stability with well-retained CO conversion (∼95.0%) and Pt NCs (∼1.20 nm) in the long term water-gas shift (WGS) reaction. More importantly, the Pt-mpTiO2 displays an unusual increasing activity during the cyclic catalyzing WGS reaction, which was found to stem from the in situ generation of interfacial active sites (Ti3+-Ov-Ptδ+) by the reduction effect of spillover hydrogen generated at the stably supported Pt NCs. The Pt-mpTiO2 catalysts also show superior performance toward the selective hydrogenation of furfural to 2-methylfuran. This work discloses an efficient and robust Pt-mpTiO2 catalyst and systematically elucidates the mechanism underlying its unique catalytic activity, which helps to design stable SMC catalysts with self-enhancing interfacial activity in sustainable heterogeneous catalysis.

Self-Hybrid Transition Metal Oxide Nanosheets Synthesized by a Facile Programmable and Scalable Carbonate-Template Method.

2D transition metal oxides (TMO) nanosheets have attracted considerable attention in both fundamental research and practical applications. Herein, a convenient programmable and scalable carbonate crystals templating synthesis is developed to produce high-quality self-hybrid TMO nanosheets (Si-WO3- x , Tax Oy , Mnx Oy ) and their respective polymetallic oxide hybrid nanosheets with tunable composition, low-cost and high-yield. Taking tungsten oxide nanosheets as example, silicotungstic acid precursor is in situ converted into tungsten oxide nanosheets like scales on the surface of calcium carbonate crystals through the simple soaking-drying-calcination process, and after selectively dissolving calcium carbonate by etching, the dispersive tungsten oxide nanosheets with unique self-hybrid Si-doped h-WO3 /ε-WO3 /WO2 compositions are obtained, which show excellent acetone gas-sensing performances at low temperatures. This carbonate-template method opens up the possibility to economically produce various functional TMO nanosheets with specific compositions for diverse applications.

Sustained-Release Solid Dispersion of High-Melting-Point and Insoluble Resveratrol Prepared through Hot Melt Extrusion to Improve Its Solubility and Bioavailability.

This study aimed to prepare a sustained-release solid dispersion of poorly water-soluble resveratrol (RES) with high melting point in a single hot melt extrusion step. A hydrophobic-hydrophilic polymeric blend (Eudragit RS and PEG6000) was used to control the release of RES. With the dispersive mixing and high shear forces of hot melt extrusion, the thermodynamic properties and dispersion of RES were changed to improve its solubility. The effects of the formulation were investigated through univariate analysis to optimize the preparation of the sustained-release solid dispersion. In vitro and in vivo studies were performed to evaluate the prepared RES/RS/PEG6000 sustained-release solid dispersion. The physical state of the solid dispersion was characterized using differential scanning calorimetry and X-ray diffraction. Surface properties of the dispersion were visualized using scanning electron microscopy, and the chemical interaction between RES and excipients was detected through Fourier-transform infrared spectroscopy. Results suggested that the optimized sustained-release solid dispersion was obtained when the mass ratio of RES-polymeric blend was 1:5, the ratio of PEG6000 was 35%, the barrel temperature was 170 °C, and the screw speed was 80 rpm. In vitro studies demonstrated that the solid dispersion showed a good sustained release effect. The cumulative release of RES reached 82.42% until 12 h and was fit by the Weibull model. In addition, the saturated solubility was 2.28 times higher than that of the bulk RES. In vitro studies demonstrated that the half-life increased from 3.78 to 7.09 h, and the bioavailability improved to 140.38%. The crystalline RES was transformed into the amorphous one, and RES was highly dispersed in the polymeric blend matrix.

Size-Controlled Au Nanoparticles Incorporating Mesoporous ZnO for Sensitive Ethanol Sensing.

Zinc oxide (ZnO) as a commonly used semiconductor material has aroused extensive research attention in various fields, such as field-effect transistors, solar cells, luminescent devices, and sensors, because of its excellent light-electrical features and large exciton bonding energy. Herein, ultrasmall Au nanoparticles with tunable size decorated mesoporous ZnO nanospheres were synthesized via facile formaldehyde-assisted metal-ligand cross-linking strategy, where these active Au species could be transferred into Au nanoparticles in the frameworks by various reduction strategies. Typically, mesoporous ZnO-Au with a photoreduction technique showed superior ethanol sensing performance (ca. 159 for 50 ppm at 200 °C) because of its high surface area, dual-mesoporous structure, and interface effect (electron effect, surface catalytic/adsorption). Moreover, the mesoporous ZnO-Au composites by photoreduction show much better performance than those via H2 reduction and NaBH4 reduction, which is ascribed to the providential size of Au nanoparticles (ca. 6.6 nm) and abundant oxygen defects in the composites. In particular, the selectivity and sensitivity of mesoporous ZnO-Au far exceeds those of materials loaded with other noble metals (Pt, Pd, and Ag). The sensing mechanism of mesoporous ZnO-Au for ethanol is attributed to classical surface adsorption/catalytic reaction, where strong sensitization effect (electron and chemical) and the spillover effect of Au nanoparticles in the catalytic reaction cause superior ethanol sensing performances. In situ FTIR and GC-MS measurement revealed that the catalytic oxidation of ethanol follows the process of dehydrogenation and deep oxidation, that is, dehydrogenation to acetaldehyde, and then further oxidation to carbon dioxide and water.

Smart Cargo Delivery System based on Mesoporous Nanoparticles for Bone Disease Diagnosis and Treatment.

Bone diseases constitute a major issue for modern societies as a consequence of progressive aging. Advantages such as open mesoporous channel, high specific surface area, ease of surface modification, and multifunctional integration are the driving forces for the application of mesoporous nanoparticles (MNs) in bone disease diagnosis and treatment. To achieve better therapeutic effects, it is necessary to understand the properties of MNs and cargo delivery mechanisms, which are the foundation and key in the design of MNs. The main types and characteristics of MNs for bone regeneration, such as mesoporous silica (mSiO2 ), mesoporous hydroxyapatite (mHAP), mesoporous calcium phosphates (mCaPs) are introduced. Additionally, the relationship between the cargo release mechanisms and bone regeneration of MNs-based nanocarriers is elucidated in detail. Particularly, MNs-based smart cargo transport strategies such as sustained cargo release, stimuli-responsive (e.g., pH, photo, ultrasound, and multi-stimuli) controllable delivery, and specific bone-targeted therapy for bone disease diagnosis and treatment are analyzed and discussed in depth. Lastly, the conclusions and outlook about the design and development of MNs-based cargo delivery systems in diagnosis and treatment for bone tissue engineering are provided to inspire new ideas and attract researchers' attention from multidisciplinary areas spanning chemistry, materials science, and biomedicine.

Air Pollution Reduces Interpersonal Trust: The Roles of Emotion and Emotional Susceptibility.

Air pollution has been shown to have detrimental effects on physical and mental health, yet little is known about how air pollution affects psychosocial functioning in everyday life. We conducted three studies that utilized experimental methods and web crawler technology to examine the effect of hazy environmental conditions on perceived interpersonal trust, and to investigate the roles of emotion and emotional susceptibility in mediating or moderating the negative impact of air pollution. In Study 1, participants were presented with landscape photos that showed either hazy scenes or clear scenes. Those who viewed photos of hazy scenes reduced their levels of interpersonal trust. In Study 2, emotion data were collected from social media with web crawler technology, in connection with meteorological monitoring data during the same period. Hazy conditions were associated with reduced expressions of positive emotion on social media, whereas clearer conditions were associated with enhanced positive emotional expressions. In Study 3, we simulated Weibo communications in the laboratory. The findings showed that emotional susceptibility moderated the negative effect of hazy conditions on interpersonal trust, and negative emotion mediated the effect of hazy conditions on interpersonal trust. The findings advance the understanding of the impact of air pollution on interpersonal trust and social relations and the associated psychological mechanisms and boundary conditions. They have important real-life implications.

Whispering-Gallery Mode Lasing in Perovskite Nanocrystals Chemically Bound to Silicon Dioxide Microspheres.

Cesium lead halide perovskite nanocrystals exhibit high photoluminescence quantum efficiencies and tunability across the visible spectrum. This makes these crystals ideal candidates for solar panels, light-emitting diodes, lasers, and especially nanolasers. Due to the versatility of cation substitution in perovskite nanocrystals, they can be grown on amine-functionalized silicon dioxide nanoparticles, where the amine linker replaces the standard cation structure. Selectively growing luminescent nanocrystals on spherical silicon dioxide microspheres results in the opportunity to populate whispering-gallery modes in these spherical silica microspheres. In this case, the nanocrystal halide composition can be used to selectively tune the emission wavelength mode, and microsphere radius to tune the mode spacing. This silicon dioxide attachment also adds to the overall stability of the system. Through photoluminescence microscopy measurements, we show whispering gallery modes in individual perovskite-coated microspheres for CsPbBr3 and CsPbI3 nanocrystals on 9.2 µm diameter silica spheres and compare these to theoretically predicted optical modes. In CsPbBr3, we provide evidence that these modes will lase under optical excitation, with a threshold of 750 µJ/cm2. This study presents a novel system that, through optimization, could be a promising pathway to achieve facile and stable perovskite nanolasers.

3,5-Diaryl-1H-pyrazolo[3,4-b]pyridines as potent tubulin polymerization inhibitors: Rational design, synthesis and biological evaluation.

A series of novel 3,5-diaryl-1H-pyrazolo[3,4-b]pyridines as tubulin polymerization inhibitors targeting the colchicine site were designed via ring tethering strategy, which was supported by conformational analysis. The general, chemically unstable and rotational linker, carbanyl group, was locked by 1H-pyrazolo[3,4-b]pyridine to avoid carbonyl reduction and restrict the instability of molecular conformation caused by the rotation of the carbon-carbon single bond beside carbonyl group. All of target compounds were synthesized and evaluated for their antiproliferative activities against three human cancer lines (SGC-7901, A549 and HeLa) by MTT assay. Most of these compounds showed prominent in vitro potency and the most potent compound in this scaffold 13d (SGC-7901: IC50 = 13 nM) could significantly inhibit tubulin polymerization and strongly disrupt cytoskeleton. The results of molecular modeling study revealed that 13d interacts with tubulin by binding to the colchicine site.

Structure and electrochemical properties of copper wires with seamless 1D nanostructures.

A seamless Cu nanowire array grown on Cu wire is prepared by combining thermal oxidation method and electrochemical reduction. The data set described in this paper includes the structure of the Cu nanowires electrode, electrocatalytic active surface area, linear sweep voltammetry and amperometry measurement for nitrate sensing. The electrochemical data show that Cu nanowire arrays exhibited a linear response to nitrate ions over a concentration range from 50 µM to 600 µM (R2 = 0.9974) with a sensitivity of 0.357 µA µM-1 cm-1 and detection limit of 12.2 µM at a signal-to-noise ratio of 3, respectively.

Overcoming resistance to mitochondrial apoptosis by BZML-induced mitotic catastrophe is enhanced by inhibition of autophagy in A549/Taxol cells.

OBJECTIVES: Our previous in vitro study showed that 5-(3, 4, 5-trimethoxybenzoyl)-4-methyl-2-(p-tolyl) imidazol (BZML) is a novel colchicine binding site inhibitor with potent anti-cancer activity against apoptosis resistance in A549/Taxol cells through mitotic catastrophe (MC). However, the mechanisms underlying apoptosis resistance in A549/Taxol cells remain unknown. To clarify these mechanisms, in the present study, we investigated the molecular mechanisms of apoptosis and autophagy, which are closely associated with MC in BZML-treated A549 and A549/Taxol cells. METHODS: Xenograft NSCLC models induced by A549 and A549/Taxol cells were used to evaluate the efficacy of BZML in vivo. The activation of the mitochondrial apoptotic pathway was assessed using JC-1 staining, Annexin V-FITC/PI double-staining, a caspase-9 fluorescence metric assay kit and western blot. The different functional forms of autophagy were distinguished by determining the impact of autophagy inhibition on drug sensitivity. RESULTS: Our data showed that BZML also exhibited desirable anti-cancer activity against drug-resistant NSCLC in vivo. Moreover, BZML caused ROS generation and MMP loss followed by the release of cytochrome c from mitochondria to cytosol in both A549 and A549/Taxol cells. However, the ROS-mediated apoptotic pathway involving the mitochondria that is induced by BZML was only fully activated in A549 cells but not in A549/Taxol cells. Importantly, we found that autophagy acted as a non-protective type of autophagy during BZML-induced apoptosis in A549 cells, whereas it acted as a type of cytoprotective autophagy against BZML-induced MC in A549/Taxol cells. CONCLUSIONS: Our data suggest that the anti-apoptosis property of A549/Taxol cells originates from a defect in activation of the mitochondrial apoptotic pathway, and autophagy inhibitors can potentiate BZML-induced MC to overcome resistance to mitochondrial apoptosis.

Design and synthesis of 5-aryl-4-(4-arylpiperazine-1-carbonyl)-2H-1,2,3-triazole derivatives as colchicine binding site inhibitors.

A series of 5-aryl-4-(4-arylpiperazine-1-carbonyl)-2H-1,2,3-triazol derivatives were designed as potential microtubule targeting agents. The regioselective alkylation of 5-aryl-4-(4-arylpiperazine-1-carbonyl)-2H-1,2,3-triazole was predicted by computations and confirmed by an unambiguous synthetic route. The antiproliferative activity of the synthesized compounds was tested in vitro using three human cancer cell lines and some compounds exhibited significant antiproliferative activity, which suggested the reasonability of introduction of the 1,2,3-triazole fragment. Among them, compound 7p showed highest activity with the IC50 values at nanomolar level towards all three cell lines, which were comparable to the positive control, CA-4. Tubulin polymerization assay, immunofluorescence studies, cell cycle analysis and competitive tubulin-binding assay strongly proved that 7p is a colchicine binding site inhibitor of tubulin. Thus, 7p was identified as a promising drug candidate for further development of colchicine binding site inhibitors.

BZML, a novel colchicine binding site inhibitor, overcomes multidrug resistance in A549/Taxol cells by inhibiting P-gp function and inducing mitotic catastrophe.

Multidrug resistance (MDR) interferes with the efficiency of chemotherapy. Therefore, developing novel anti-cancer agents that can overcome MDR is necessary. Here, we screened a series of colchicine binding site inhibitors (CBSIs) and found that 5-(3, 4, 5-trimethoxybenzoyl)-4-methyl-2-(p-tolyl) imidazol (BZML) displayed potent cytotoxic activity against both A549 and A549/Taxol cells. We further explored the underlying mechanisms and found that BZML caused mitosis phase arrest by inhibiting tubulin polymerization in A549 and A549/Taxol cells. Importantly, BZML was a poor substrate for P-glycoprotein (P-gp) and inhibited P-gp function by decreasing P-gp expression at the protein and mRNA levels. Cell morphology changes and the expression of cycle- or apoptosis-related proteins indicated that BZML mainly drove A549/Taxol cells to die by mitotic catastrophe (MC), a p53-independent apoptotic-like cell death, whereas induced A549 cells to die by apoptosis. Taken together, our data suggest that BZML is a novel colchicine binding site inhibitor and overcomes MDR in A549/Taxol cells by inhibiting P-gp function and inducing MC. Our study also offers a new strategy to solve the problem of apoptosis-resistance.

Release behavior and formation mechanism of polycyclic aromatic hydrocarbons during coal pyrolysis.

Polycyclic aromatic hydrocarbons (PAHs) are major environmental pollutants. They have attracted considerable attention due to their severe potential carcinogenic, mutagenic and genotoxic effects on human health. In this study, five different rank coals from China were pyrolyzed using pyro-probe CDS 5250 and the release behavior of 16 PAHs under different pyrolysis conditions were studied by Gas Chromatography-Mass Spectrometer (GC-MS). The structural characteristics of the five coals were determined by Cross-Polarization/Magic Angle Spinning Carbon-13 Nuclear Magnetic Resonance (CP/MAS (13)C NMR) spectroscopy, and then the factors influencing the formation of PAHs during coal pyrolysis were discussed together with the coal structural data. It was shown that the amount of PAHs generated during coal pyrolysis was largely related to coal rank and followed the order of medium metamorphic coal > low metamorphic coal > high metamorphic coal. The amount of total PAHs varied as the temperature was increased from 400 °C to 1200 °C, which showed a trend of first increasing and then decreasing, with the maximum value at 800 °C. Moreover, the species of PAHs released varied with pyrolysis temperatures. When the temperature was lower than 800 °C, the small ring PAHs were the most abundant, while the proportion of heavy rings increased at higher temperature. The results indicate that the formation of PAHs during coal pyrolysis depends on the structure of the coal. The species and amounts of PAHs generated during coal pyrolysis are closely related to the contents of protonated aromatic carbons and bridging ring junction aromatic carbons present in the coal structure.