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The design of semiconductors with excellent charge separation and photothermal conversion efficiency is crucial for solar-driven photocatalytic hydrogen production. Herein, a narrow-bandgap semiconductor junction by growing Bi 2 S 3 nanosheets on ReS 2 nanoflowers is designed for efficient photothermal-assisted photocatalytic hydrogen generation. The Bi 2 S 3 /ReS 2 hybrids featuring a distinctive 3D flower-like morphology and 2D/2D heterointerfaces are prepared via a handy method. The synergistic excitations of the narrow bandgaps endow these hybrids with a broad light absorption spectrum, ranging from the ultraviolet to the near-infrared region. Additionally, the Bi 2 S 3 /ReS 2 hybrids demonstrate superior photothermal conversion in both solution and solid states, originating from the efficient light absorption and nonradiative relaxation of lattice thermal vibrations. The well-matched band alignment of the two narrow-bandgap semiconductors confers upon the hybrids a built-in electric field and a Z-scheme charge-transfer pathway, significantly enhancing charge separation and suppressing the charge recombination. Under simulated solar light irradiation, the ReS 2 /Bi 2 S 3 hybrids exhibit a substantially enhanced photocatalytic hydrogen generation rate, which is 38.5 times and 7.36 times that of ReS 2 and Bi 2 S 3 , respectively. Temperature-dependent photocatalytic experiments reveal that the hybrids' excellent photothermal conversion contributes to about a 23 % improvement on photocatalysis compared to that tested at low temperature. This improvement is attributed to the local temperature rise, which further enhances charge transfer efficiency and the hydrogen reduction reaction. This study offers an inspiration for the design of photocatalysts based on narrow-bandgap semiconductors for photothermal-assisted photocatalysis. • The Bi 2 S 3 /ReS 2 hybrids with 3D morphology and 2D/2D interfaces are prepared. • Narrow bandgap excitations endow the hybrids with wide light absorption. • The hybrid has excellent photothermal conversion performance. • The hybrids show higher photocatalytic performance compared with ReS 2 and Bi 2 S 3. • The photothermal effect contributes to about 23 % improvement on photocatalysis. [ABSTRACT FROM AUTHOR]

Dioritic--trondhjemitic gneisses of Neoarchean age are widely distributed throughout the Gualanyu--Shangying area in Eastern Hebei, North China Craton. These orthogneisses consist of dioritic, trondhjemitic, and quartz-rich trondhjemitic gneisses, which were subjected to amphibolite- to granulite-facies metamorphism. LA-ICP-MS zircon U--Pb isotopic dating reveals that the magmatic precursors of these rocks were contemporaneously emplaced from 2535 ± 23 to 2513 ± 8 Ma, reflecting an important Neoarchean dioritic--trondhjemitic magmatic event followed by sequential Proterozoic tectonothermal events between 2472 ± 60 and 2307 ± 50 Ma. Dioritic and trondhjemitic gneisses exhibit similar zircon ɛHf(t) values of +1.5 to +5.2 and +2.9 to +5.3, respectively, indicating their depleted mantle affinity. Geochemical analysis reveals that the dioritic gneisses have low SiO2 contents (55.4-63.0%), various MgO contents (2.07-4.78%) and Mg# (36.07-63.56), and high (La/Yb)N ratios (5.45-15.19). In contrast, the trondhjemitic gneisses exhibit higher SiO2 contents (67.4-73.8%) and (La/Yb)N ratios (12.86-76.73), and lower MgO contents (0.66-2.67%), although their Mg# (36.29-61.41) are similar to those of dioritic gneisses. These geochemical and zircon Lu--Hf isotopic features, together with geochemical modeling, suggest that the dioritic magmas were derived mainly from the partial melting of a depleted mantle wedge that was metasomatized by slab-derived melts or fluids, and that the trondhjemitic magmas were formed by fractional crystallization of the dioritic magmas. Quartz-rich trondhjemitic gneisses exhibit extremely high SiO2 contents (77.4-84.6%) with zircon ɛHf(t) values ranging from -3.4 to +4.1, suggesting that their precursors formed after the partial melting of a mixed magmatic source. It is suggested that the precursors comprised a mafic member derived from a mantle wedge altered by oceanic slab melts or fluids, and a felsic member derived from the partial melting of ancient crustal material. These new data, combined with previous studies of contemporaneous metavolcanic rocks in Gualanyu-Shangying area and surrounding areas, suggest that the magmatic precursors of these Neoarchean dioritic--trondhjemitic gneisses formed in a subduction-related tectonic environment at an E-W strike convergent plate margin. Furthermore, the Eastern Block of the North China Craton had a major lateral accretion of crustal growth in the north margin in the Neoarchean, whereas vertical crustal growth and recycling under plume tectonic backgrounds occurred in the interior of the Eastern Block. [ABSTRACT FROM AUTHOR]

Abstract: In the hormone-refractory stage of prostate cancer (PC), the expression of prostate-specific antigen (PSA) and prostate-specific membrane antigen (PSMA) often remains highly active. Accumulating studies have demonstrated that these two proteins are attractive targets for specific delivery of functional molecules to advanced PC, not merely as potential sensitive markers for PC detection. In this study, we constructed a dual-modified liposome that incorporated PSA-responsive and PSMA-mediated liposomes and potentially offers double selectivity for PC. The folate moiety binds quickly to PSMA-positive tumors, and the PSA-responsive moiety is cleaved by PSA that was enriched in tumor tissues. The activated liposomes (folate and cell-penetrating peptides dual-modifications) are subsequently taken up by the tumor cells via polyarginine's penetrating effects and receptor-mediated endocytosis. To corroborate these assumptions, a series of experiments were conducted, including PSA-responsive peptide hydrolysis kinetics, cellular uptake, internalization mechanism and escape from endosomes in PC-3 and/or 22Rv1 cells, biodistribution and antitumor activity of siRNA-loaded liposomes after systemic administration, gene silencing and cell apoptosis in vitro and in vivo. The results reveal that multivalent interactions play a key role in enhancing PC cell recognition and uptake while reducing nonspecific uptake. The dual-modified liposomes carrying small interfering RNA (siRNA) have significant advantages over the control liposomes, including single-modified (folate, CPP, PSA-responsive only) and non-modified liposomes. The dual-modified liposomes elevated cellular uptake, downregulated expression of polo-like kinase 1 (PLK-1) and augmented cell apoptosis in prostate tumor cells. The entry of the dual-modified liposomes into 22Rv1 cells occurred via multiple endocytic pathways, including clathrin-mediated endocytosis and macropinocytosis, followed by an effective endosomal escape of the entrapped siRNA into the cytoplasm. In vivo studies conducted on a 22Rv1 xenograft murine model demonstrated that the dual-modified liposomes demonstrated the maximized accumulation, retention and knockdown of PLK-1 in tumor cells, as well as the strongest inhibition of tumor growth and induction of tumor cell apoptosis. In terms of targeting capacity and therapeutic potency, the combination of a PSA-responsive and PSMA-mediated liposome presents a promising platform for therapy and diagnosis of PSMA/PSA-positive PC. [Copyright &y& Elsevier]

Abstract: A nanocarrier delivery system that can simultaneously deliver a chemotherapeutic drug and siRNA to the tumor is emerging as a promising treatment strategy for cancer treatment. In this study, a multifunctional PHD/PPF/siRNA complexes was developed by one-step assembly of prefunctionalized polymers: PEI–HZ–DOX (PHD) and PEI-PEG-Folate (PPF) with siRNA. The PHD, a conjugate of PEI (polyethylenimine) with doxorubicin (DOX) via a pH-responsive hydrazone linkage, enables pH-controlled drug release. The PPF, a tumor-targeting folate ligand conjugated to PEI using polyethyleneglycol (PEG) as a linker, enables immune evasion and cell-specific targeting. The prefunctionalized PHD and PPF as well as the self-assembly complexes reveals advantage on safety in further application for siRNA delivery. By exploiting distinct triple ratios of PHD, PPF and siRNA during nanocomplexes formulation, the folate surface density, DOX loading amount and siRNA complexation can be precisely and reproducibly changed. The studies showed that the complexes was capable of delivering siRNA and DOX to cancerous cells and release synchronously in cell by acid-triggered manner, i.e. hydrazone bond cleavage and endosome/lysosome escape using flow cytometry and confocal laser scanning microscopy analysis. The results highlight the potential for therapeutic gene silencing in vitro and in vivo using RT-PCR and non-invasive in vivo imaging systems. The PHD/PPF/siRNA complexes can increase DOX and siRNA accumulation in cancerous cells and decrease the nonspecific distribution in normal tissues by the combination of EPR effect of nanocarriers, pH-triggered drug release, folate-mediated targeted delivery, and synergistic action of DOX and siRNA. [Copyright &y& Elsevier]

Abstract: Chemotherapeutic agents often cause severe side effects because they produce a similar cytotoxicity in both cancerous and healthy cells. In this study, a rational strategy was implemented to take advantage of a combination of both tumor microenvironment-sensitive polypeptides (TMSP) and folate to create a more selective and efficient drug delivery system to target cancer cells. TMSP and folate were conjugated to the distal ends of DSPE-PEG2000-maleimide and DSPE-PEG5000-amine to create DSPE-PEG2000-TMSP and DSPE-PEG5000-folate, respectively, which were incorporated onto the surface of a docetaxel-loaded nanostructured lipid carrier (F/TMSP-DTX-NLC). TMSP are comprised of polycationic cell-penetrating peptides (CPP) and polyanionic inhibitory peptides, which are coupled via a proteinase-sensitive cleavable linker. The linker can be cleaved in the presence of matrix metalloprotease-2 and -9 (MMP-2/9). TMSP provides the ability to enhance specific cancer cellular uptake after selectively unmasking polyanionic inhibitory peptides in MMP-2/9 protease-oversecretion tumor tissue, whereas in circulation, the penetration is shielded. The folate moiety binds selectively to folate receptor-positive tumors. The cleaved dual-modified nanocarriers are then taken up by the tumor cells via both receptor-mediated endocytosis and CPP penetrating action to overcome the higher interstitial pressure in the tumor. The nanocarrier system demonstrated a small size, high encapsulation efficiency (>95%), sustained release and targeted delivery. The strong cellular uptake and cytotoxic activity of dual-modified F/TMSP-DTX-NLC in KB, HT-1080, MCF-7 and A549 cells verified the correlation with folate receptor expression and MMP-2/9 secretion. The remarkable penetration into KB and HT-1080 multicellular tumor spheroids confirmed that the temporary mask of the polyanionic inhibitory peptide in TMSP does not disturb the penetration ability of CPP in the tumor microenvironment with abundant proteases. Furthermore, the active targeting and triggered activation exhibited higher antitumor efficacy and lower systemic toxicity with the KB tumor model in nude mice compared to the nonmodified DTX-NLC and Taxotere®. These results suggested that the application of combined TMSP and folate modifications may be an approach in the selectively targeted delivery of anticancer drugs with low systemic toxicity. [Copyright &y& Elsevier]

Abstract: To overcome the poor aqueous solubility of docetaxel (DTX) and the side effects of the emulsifier in the marketed formulation, we have developed a DTX-loaded micelle using a nontoxic and biodegradable amphiphilic diblock copolymer, methoxy polyethylene glycol-distearoylphosphatidylethanolamine (mPEG2000-DSPE). The prepared micelles exhibited a core–shell structure, and DTX was successfully encapsulated in the core with an encapsulation efficiency of 97.31±2.95% and a drug loading efficiency of 3.14±0.13%. The micelles were spherical with a hydrodynamic diameter of approximately 20nm, which could meet the requirement for in vivo administration, and were expected to enhance the drug''s antitumor efficacy and to decrease its toxicity. To evaluate the DTX-loaded micelles, we chose a well marketed formulation, Taxotere®, as the control. The prepared DTX micelle had a similar antiproliferative effect to Taxotere® in vitro but a significantly better antitumor efficacy than Taxotere® in vivo, which may be caused by passive targeting of the tumor by the micelles. In addition, the safety evaluation revealed that the DTX micelle was a qualified drug for use in vivo. Based on the experimental results, we propose that mPEG2000-DSPE micelle is a potent carrier for DTX. [Copyright &y& Elsevier]

Abstract: This paper studies interfacial debonding behavior of composite beams which include piezoelectric materials, adhesive and host beam. The focus is put on crack initiation and growth of the piezoelectric adhesive interface. Closed-form solutions of interface stresses and energy release rates are obtained for adhesive layer in the piezoelectric composite beams. Finite element analyses have been carried out to study the initiation and growth of interfaces crack for piezoelectric beams with interface element by ANSYS, in which the interface element of FE model is based on the cohesive zone models to characterize the fracture behavior of the interfacial debonding. The results have been compared with analytical solution, and the influence of different geometry and material parameters on the interfacial behavior of piezoelectric composite beams have been discussed. [Copyright &y& Elsevier]

Abstract: By deriving analytical formulae for the quantization accuracy of the acoustoelectric current, we reveal that: (1) the flatness of the current plateau for the typical present devices has reached the theoretical limit of about 100 ppm over a 1/1000 change of the gate voltage; (2) increasing the transport channel length, and counterintuitively, increasing the acoustic wavelength as well, would improve the quantization accuracy, and very promisingly up to 0.01 ppm as required for a quantum current standard. [Copyright &y& Elsevier]

Nanoparticles (NPs) serve as versatile delivery systems for anticancer, antibacterial, and antioxidant agents. The manipulation of protein–NP interactions within biological systems is crucial to the application of NPs in drug delivery and cancer nanotherapeutics. The protein corona (PC) that forms on the surface of NPs is the interface between biomacromolecules and NPs and significantly influences their pharmacokinetics and pharmacodynamics. Upon encountering proteins, NPs undergo surface alterations that facilitate their clearance from circulation by the mononuclear phagocytic system (MPS). PC behavior depends largely on the biological microenvironment and the physicochemical properties of the NPs. This review describes various strategies employed to engineer PC compositions on NP surfaces. The effects of NP characteristics such as size, shape, surface modification and protein precoating on PC performance were explored. In addition, this study addresses these challenges and guides the future directions of this evolving field. [ABSTRACT FROM AUTHOR]

Cancer is a complex pathological phenomenon that needs to be treated from different aspects. Herein, we developed a size/charge dually transformable nanoplatform (PDR NP) with multiple therapeutic and immunostimulatory properties to effectively treat advanced cancers. The PDR NPs exhibit three different therapeutic modalities (chemotherapy, phototherapy and immunotherapy) that can be used to effectively treat primary and distant tumors, and reduce recurrent tumors; the immunotherapy is simultaneously activated by three major pathways, including toll-like receptor, stimulator of interferon genes and immunogenic cell death, effectively suppresses the tumor development in combination with an immune checkpoint inhibitor. In addition, PDR NPs show size and charge responsive transformability in the tumor microenvironment, which overcomes various biological barriers and efficiently delivers the payloads into tumor cells. Taking these unique characteristics together, PDR NPs effectively ablate primary tumors, activate strong anti-tumor immunity to suppress distant tumors and reduce tumor recurrence in bladder tumor-bearing mice. Our versatile nanoplatform shows great potential for multimodal treatments against metastatic cancers. [ABSTRACT FROM AUTHOR]

We analysed the global protein expression in seeds of a high-oil soybean cultivar (Jiyu 73, JY73) by proteomics. More than 700 protein spots were detected and 363 protein spots were successfully identified. Comparison of the protein profile of JY73 with that of a high-protein cultivar (Zhonghuang 13, ZH13) revealed 40 differentially expressed proteins, including oil synthesis, redox/stress, hydrolysis and storage-related proteins. All redox/stress proteins were less or not expressed in JY73, whereas the expression of the major storage proteins, nitrogen and carbon metabolism-related proteins was higher in ZH13. Biochemical analysis of JY73 revealed that it was in a low oxidation state, with a high content of polyunsaturated fatty acids and vitamin E. Vitamin E was more active than antioxidant enzymes and protected the soybean seed in a lower oxidation state. The characteristics of high oil and high protein in soybean, we revealed, might provide a reference for soybean nutrition and soybean breeding. [ABSTRACT FROM AUTHOR]

Abstract: MnWO4 nanoparticles were prepared using a microwave-assisted method followed by low-temperature treatment. The crystal quality and optical property of the MnWO4 nanoparticles were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy, and ultraviolet–visible (UV–vis) absorption spectroscopy. Our results show that good crystal quality MnWO4 nanoparticles can be prepared by the microwave-assisted method, and best crystal quality nanoparticles can be obtained with synthesizing pH value of 7. Furthermore, by calcination treatments, crystal quality can be further improved with less defect states and the particle size increases when the calcining temperature increases from 150 to 600°C. In addition, our study shows that the MnWO4 nanoparticles have strong absorption in the visible light region, suggesting that these nanoparticles are promising for photocatalytic applications. [Copyright &y& Elsevier]

The purpose of the study was to (i) prepare the chitosan/Kollicoat SR 30D film-coated pellets for colonic drug delivery, and (ii) evaluate the colonic delivery and efficacy of these coated pellets in the rat. The pellets were coated to different film thickness with chitosan/Kollicoat SR 30D formulations. In vitro drug release was assessed in simulated gastrointestinal (GI) tract conditions. Biodistribution of aminosalicylates (5-ASA) in GI tract and plasma was measured after oral administration of coated or uncoated 5-ASA pellets. Efficacy of the coated or uncoated 5-ASA pellets was tested in 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced rat colitis model. Healing of induced colitis was assessed by measuring the myeloperoxidase activities, colon wet weight/body weight, and damage score. The coating was susceptible to bacteria digestion, resulting in an increase in the release of 5-ASA from the coated pellets. After administration of the coated pellets, the drug concentration in the large intestine was higher than those of uncoated pellets. In plasma, the observed mean Cmax from the coated pellets was significantly lower than that of the uncoated pellets. Chitosan/Kollicoat SR 30D film-coated pellets could deliver the 5-ASA to the targeted site, providing effective treatment for inflammatory bowel disease. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 99:186–195, 2010 [ABSTRACT FROM AUTHOR]

Abstract: The purpose of the present study is to assess the biodistribution and pharmacokinetics of pectin/ethylcellulose film-coated and uncoated pellets containing 5-fluorouracil (5-FU) in rats. Both coated and uncoated pellets were orally administered to the rats at a dosage equivalent to 15mg/kg. 5-FU concentrations in different parts of the gastrointestinal (GI) tract and plasma were quantitatively analyzed using a high-performance liquid chromatography (HPLC) assay. 5-FU released from uncoated pellets mainly distributes in the upper GI tract, however, 5-FU released from coated pellets mainly distributes in the cecum and colon. In plasma, the observed mean C max from the coated pellets group (3.65±2.3μg/mL) was lower than that of the uncoated pellets group (23.54±2.9μg/mL). The AUC values obtained from the uncoated pellets and the coated pellets were 49.08±3.1 and 9.06±1.2μgh/mL, respectively. The relatively high local drug concentration with prolonged exposure time provides a potential to enhance anti-tumor efficacy with low systemic toxicity for the treatment of colon cancer. [Copyright &y& Elsevier]