Search

To determine the expression and function of glutamate-cysteine ligase catalytic (GCLC) and glutamate-cysteine ligase catalytic modifier (GCLM) in gastric adenocarcinoma.Bioinformatics was used to analyze the expression of GCLC and GCLM. We download and analyzed the expression of gastric adenocarcinoma patients from TCGA database. Moreover, the method of immunochemistry was used to verify the expression of GCLC and GCLM in gastric adenocarcinoma.At first, the expression of GCLC and GCLM in gastric adenocarcinoma tissues were both significantly higher compared with normal tissues analyzed via TCGA database. Then, gastric adenocarcinoma tissues were collected and performed with immunochemistry. The gastric adenocarcinoma with positive staining for GCLC and GCLM was 77% and 80%, respectively, which was significantly higher compared with adjacent normal tissues (9% and 11%, respectively).The disordered expression of GCLC and GCLM in gastric adenocarcinoma suggested that these factors may induce tumorigenesis and may be a novel target for diagnosis and treatment of gastric adenocarcinoma.

Summary Physical unclonable function (PUF) is a cornerstone of anticounterfeiting. However, conventional PUF key-based secure tags encounter several bottlenecks, such as complicated manufacturing, specialized and tedious readout, long authentication time, and insufficient stability. Here, we utilize various two-dimensional materials (2DMs), including Ti3C2Tx MXene and graphene oxide, to construct multigenerational microstructures as PUF patterns. Two intermediate treatments, cation intercalation and moisture-induced lubrication, are introduced in between sequential contractions to engineer the multiscale patterns in a transfer-free and scalable fashion. A deep learning (DL)-facilitated software is developed to pre-categorize the hierarchical topographies with classifiable features. Thereafter, the search-and-compare is conducted within a smaller database to shorten the overall authentication time. The synergy between 2DM tags and DL-facilitated software enables a reliable and environmentally stable anticounterfeiting technology, DeepKey, showing superior encoding capacity (>10144,494) and short authentication time (∼3.5 min). Our 2DM anticounterfeiting tag is finally integrated with QR codes to provide two-layer information security.

Long noncoding RNAs (lncRNAs) have been implicated in a range of developmental processes and diseases, but the roles and mechanisms by which they act in adipogenic differentiation and adipose tissue biology are still unknown. By comparing the different expression patterns of lncRNAs before and after the adipocyte differentiation of human adipose-derived mesenchymal stem cells (hADSCs), we characterized a novel lncRNA, AC092834.1, which is significantly increased in preadipocytes. By gain- and loss-of-function experiments, we demonstrated that lncRNA AC092834.1 potentiated adipogenic differentiation through directly increasing the level of expression of DKK1, which competitively binds with LRP5 to inhibit the Wnt-β-catenin pathway and reduce the inhibition of adipogenesis by Wnt signaling. This finding provides novel mechanistic insights into a critical role for lncRNA AC092834.1 as a regulator of adipogenic differentiation, which expands our knowledge about the molecular mechanisms of obesity and other adipogenic differentiation-related disorders.

BACKGROUND CONTEXT Coexistence of abnormal skeletal growth and reduced bone mineral density in the context of adolescent idiopathic scoliosis (AIS) suggests disturbed bone metabolism existing in such patients. Our previous study suggested increased proliferation ability and decreased osteogenic differentiation ability of bone marrow mesenchymal stem cells (BM-MSCs) of AIS. PURPOSE To explore the differential miRNA expression profile, Go (gene ontology) terms and KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways in BM-MSCs of AIS and non-AIS controls were conducted using microarray approach and bioinformatics analyses. STUDY DESIGN miRNA microarray approach and bioinformatics analysis. METHODS The differentially expressed miRNAs (DEMs) of BM-MSCs from AIS patients compared with those from healthy individuals were analyzed using a microarray analysis. Comprehensive bioinformatics analyses were then used to enrich datasets for gene ontology and pathway. Based on the interaction network analysis of DEMs contained in significant pathways, 12 potential crucial miRNAs were selected for validation by RT-PCR. RESULTS The study identified 54 previously unrecognized DEMs (12 upregulated, 42 downregulated) in BM-MSCs from AIS patients. These miRNAs are involved in multiple biological processes, including small GTPase-mediated signal transduction, DNA-dependent transcription, cytokinesis, cell adhesion, transmembrane transport, response to hypoxia, etc. Pathway analysis of these new identified miRNAs revealed dysregulated MAPK signaling pathway, PI3K-Akt signaling pathway, calcium signaling pathway, Notch signaling pathway, and ubiquitin-mediated proteolysis pathway, all of which have been reported to play important role in regulating the osteogenic or adipogenic differentiation of MSCs. Furthermore, interaction networks analysis indicated that seven most significant central miRNAs, including miR-17-5p, miR-106a-5p, miR-106b-5p, miR-16-5p, miR-93-5p, miR-15a-5p, and miR-181b-5p may play essential roles in AIS pathogenesis and accompanied osteopenia. CONCLUSION The current study reports the differential miRNAs expression profiles of BM-MSCs from AIS patients and related pathways for the first time. The identification of these candidate miRNAs provides a deep insight into the pathogenesis of AIS and the accompanying generalized osteopenia.

In this work, a novel electrochemical immunosensor was designed for ultrasensitive determination of carcinoembryonic antigen based on 3D-structured rGO/Ag-Au NPs. 3D-rGO-MWCNTs nanocomposites feature network structure which has a large specific surface area and excellent conductivity providing more active sites for Ag-Au bimetallic nanoparticles. At the same time, the synergistic effect of 3D-rGO-MWCNTs and Ag-Au NPs, significantly improved the electrochemical performance of the modified electrode. Due to the excellent biocompatibility of Ag-Au NPs, the antibody could be well attached to the electrode, and the immunosensor could be successfully prepared. Under the optimized conditions, the constructed immunosensor showed a wide linear range from 0.001 ng mL−1 to 80 ng mL−1 with the detection limit of 3 pg mL−1 (S/N ratio of 3). The proposed immunosensor has excellent analytical performance including good stability, reproducibility and selectivity, and was successfully applied to the detection of CEA in human serum verified its practicability.

Background: K. pneumoniae can cause a wide range of diseases, and is highly associated with antimicrobial-resistant infections in hospitals. We aimed to characterize a five-year collection of K. pneumoniae genomes, and identify transmission events that were not identified by conventional typing approaches. Methods: From January 5, 2013 to July 24, 2018, 3,061 K. pneumoniae isolates were unbiasedly collected, and sequenced. The earliest strain recovered for each patient was retrospectively analyzed for the genomic epidemiology. Pairwise core-genome single-nucleotide polymorphism (cgSNP) distances were measured. An F1 score well differentiating isolates from the same ward and collected within 180 days was calculated. The best distance cutoffs, and the spatial-temporal information of each clone were combined to define transmission sub-lineages. Findings: A sum of 2,193 non-duplicated genomes was clustered into four species complexes. 93% (n = 2,035) was KpI with its largest clonal group being CG11 (20%, n = 406; 393 were ST11). 92% (n = 374) CG11 carried the carbapenem-resistant gene blaKPC-2. Four transmission sub- lineages (ST307-neo, ST20-neo, ST25-neo, and ST25-icu) were confidently identified by the integrated epidemiological-genomic method. None was from the high-endemic-risk clone CG11. Interpretation: Strain transmissions by low-endemic-risk clones are easy to be neglected by routine surveillance. Whole-genome sequencing analysis identified four episodes of within-ward transmissions of those neglectable clones: three in a neonatal ward, and one in ICU. Both wards are full of vulnerable patients. Thus, this study highlights the importance of including high-resolution typing technologies in infection surveillance, particularly for the neonates and critically-ill patients. Funding Information: This work was supported by National Natural Science Foundation of China [grant number 81672066 to WL]. This work was also supported by China National GeneBank (CNGB). Declaration of Interests: We declare no competing interests. Ethics Approval Statement: This study was approved by the ethics committees under tracking numbers 201806861 and BGI‐IRB 18061.

Development of metal-free carbon-based electrocatalysts with high-efficiency and excellent durability towards both oxygen and hydrogen evolution reactions (OER and HER) in a single electrolyte system is crucial yet challenging for sustainable energy generation. In this work, we report a facile and scalable strategy for fabricating self-supporting boron carbon oxynitride nanofibrous (BCNONF) mats with controllable boron contents via electrospinning and subsequent thermal treatment. Notably, the optimal BCNONF mat affords outstanding OER performance in alkaline electrolyte with low overpotential of 403 mV at 10 mA·cm−2, small Tafel slop of 72.9 mV·dec−1, and high stability (88.1% current density retention after 10 h), outperforming the commercial Ir/C benchmark. Moreover, it can serve as a remarkable HER catalyst with better stability than that of the commercial Pt/C counterpart in the same electrolyte, indicating its bifunctional characteristics. When employed as both anode and cathode of an electrolyzer, the self-supporting BCNONF mats exhibit superior activities with a potential of only 1.79 V at 10 mA·cm−2 and high long-term durability (90.6% current density retention after 50 h) for overall water splitting. Furthermore, density functional theory (DFT) calculations reveal that the remarkable OER and HER bifunctional performance of the BCNONF catalyst are originated from the reduced adsorption strength of O atom and the stronger H* adsorption on the BCNO surface as compared to those on CNO surface, which in turn facilitate efficient interfacial charge transfer between the electrocatalytic intermediates and the BCNONF catalyst.

A series of dual modified g-C3N4 (CN) composites were synthesized by integrating oxidation and doping quantum dots. Oxidation made the valance band and conduction band of the modified CN shifted to the opposite direction, resulting in higher redox activity. Meanwhile, the oxidized CN (O-CN) is more conducive to the deposition of SCNQDs due to electrostatic interaction. The introduction of sulfur-containing carbon nitride quantum dots (SCNQDs) can improve the light trapping ability and the separation efficiency of photogenerated charge-carriers. Moreover, quantum confinement effect of SCNQDs contributes to the upshift of valance band to enhance the reduction ability of composite (CN/SCNQDs), even though the band gap was not changed. The synergistic effect of dual modification made the composite (10:1-O-CN/SCNQDs) own the highest photodegradation rate of 1.43 mg/ (h·100 mg catalyst), which was 4.5, 2.0 and 1.9 times of CN, CN/SCNQDs and O-CN, respectively. Photodegradation mechanism of the composite was inferred that holes and superoxide radical played primary roles, whereas hydroxyl radical showed neglect effect. This work may provide some beneficial ideas for constructing high-performance co-modified organic photocatalysts.

International audience; Phase Change Materials (pcm) have been widely used for thermal energy storage due to their high latent heat of fusion. However, PCMs suffer from their very low thermal conductivity which limits heat spreading around the heat source. Without proper thermal conductivity enhancement, melting would occur mainly around the heat source and heat would be conducted too slowly for the device to be efficient. It is especially true when dealing with high power densities. Metallic foams are usually used as thermal conductivity enhancer, yet recent progress in additive manufacturing have allowed architected structures to be used and optimized. We present here an analytical investigation of the Effective Thermal Conductivity (etc) of porous architected structures and emphasize is made on the effect of thermal constriction at the interface with a heat spreader in contact with the heat source. To confirm the efficiency of the model, it is compared to simulation data as well as experimental data obtained using flash laser method. Flash laser method data processing had to be modified to adapt to the porous media being characterized. For that purpose, a 1D finite difference model has been developed to solve the heat equation under flash laser conditions and derive the porous material effective properties. Using this model, architected structure were proven to have an ETC up to 75% higher than the one of foam for similar porosity in particular direction of space. The validity of the above mentioned model where proven through simulation, giving an almost perfect match and experiments detailed in this paper,which showed a maximum deviation of 11%.

A series of Pb(Zr1-xTix)O3 multilayer films alternatively stacked by Pb(Zr0.52Ti0.48)O3 and Pb(Zr0.35Ti0.65)O3 layers have been deposited on corning glass by magnetron sputtering. The films demonstrate pure perovskite structure and good crystallinity. A large tetragonality (c/a) of ∼1.061 and a shift of ∼0.08 eV for optical bandgap were investigated at layer engineered films. In addition, these samples exhibited a wild tunable electro-optic behavior from tens to ∼250.2 pm/V, as well as fast switching time of down to a few microseconds. The giant EO coefficient was attribute the strain-polarization coupling effect and also comparable to that of epitaxial (001) single crystal PZT thin films. The combination of high transparency, large EO effect, fast switching time, and huge phase transition temperature in PZT-based thin films show the potential on electro-optics from laser to information telecommunication. ASTAR (Agency for Sci., Tech. and Research, S’pore) MOE (Min. of Education, S’pore) Accepted version

In this work, we report for the first time a simple approach to fabricate 3D reduced graphene oxide/boron nitride (rGO/BN) sponges with no additional chemical cross-linkers. Encouragingly, such sponge possesses higher compressibility and better recoverability in both air and organic solvents as compared to the bare rGO sponge. The as-prepared rGO/BN sponge also exhibits excellent water resistance and high oil absorption capability, achieving up to 170 times its own weight toward a wide range of environmental contaminants. Especially, the absorbed oil can be easily removed by the absorption–squeezing process which is cost effective and environmental friendly for oil collection. Most importantly, the underlying reasons for the remarkable mechanical properties, excellent oil absorption capabilities have been analysed and revealed in depth. These exceptional characteristics together with the ease of scalable synthesis make the as-prepared 3D rGO/BN sponge show many promising applications ranging from tissue engineering, sensors, catalysis, energy storage and conversion to environmental remediation. MOE (Min. of Education, S’pore)

As one of the most exciting building blocks, DNA has gained increasing attention in the construction of promising nanostructures for various biological and medical purposes. In this contribution, we have developed an easily constructed DNA nanoassembly-based biosensing system that consists of one signal hairpin probe (SHP) and one label-free hairpin probe (LHP) for target p53 gene analysis. The probes of SHP and LHP were designed to be incapable of interacting with each other in the absence of the p53 gene. When the target gene is introduced, the 3' end of SHP (or LHP) hybridizes with the middle region of LHP (or SHP), leading to polymerase-sustained DNA nanoassembly. Because one target species can exhaust many building scaffolds to execute the programmable nanoassembly in one-pot approach, the fluorescence intensity of SHP is greatly enhanced in the presence of target gene in a simple and robust manner. The practical applicability was successfully demonstrated by screening target gene extracted from cancer cells. We believe this intriguing sensing strategy and desirable assay ability would provide new opportunities to develop versatile biochemical analysis methods.

An increasingly branched rolling circle amplification (IB-RCA) which contains a padlock probe (PP) and a structurally tailored molecular beacon (MB) was innovatively developed for highly sensitive detection of cancer gene, Kras gene codon 12. In this system, the PP can be circularized after hybridization with the precisely-matched target DNA, while the stem of MB can be also opened by target DNA, resulting in hybridization with the circularized PP to generate a long tandem single-stranded DNA (ssDNA) product. Since the MB is also designed to hybridize with ssDNA product, the newly-opened MBs are able to trigger the next RCA reactions, therapy producing branched rolling circle amplification (RCA) products and in turn leading to the increasingly branched RCA (IB-RCA). This alternately and continuously operates hybridization-based MB opening and opened MBs-triggered RCA. As a result, a great number of MBs are opened that is associated with a dramatically amplified fluorescent signal, enabling to quantify target DNA down to 100 fM. This sensing method demonstrates a new concept of IB-RCA amplification even in a simple way to efficiently transduce the fluorescence signal, accomplishing the highly sensitive and selective detection of cancer gene.

In the present study, we proposed a novel dual-cyclical nucleic acid strand-displacement polymerization (dual-CNDP) based signal amplification system for highly sensitive determination of tumor suppressor genes. The system primarily consisted of a signaling hairpin probe (SHP), a label-free hairpin probe (LHP) and an initiating primer (IP). The presence of target DNA was able to induce one CNDP through continuous process of ligation, polymerization and nicking, leading to extensively accumulation of two nicked triggers (NT1 and NT2). Intriguingly, the NT1 could directly hybridize SHP, while the NT2 could act as the target analog to induce another CNDP. The resulting dual-CNDP contributed the striking signal amplification, and only a very weak blank noise existed since the ligation template of target was not involved. In this case, the target could be detected in a wide linear range (5 orders of magnitude), and a low detection limit (78 fM) was obtained, which is superior to most of the existing fluorescent methods. Moreover, the dual-CNDP sensing system provided a high selectivity towards target DNA against mismatched target and was successfully applied to analysis of target gene extracted from cancer cells or in human serum-contained samples, indicating its great potential for practical applications.

Emerging evidence indicates that microRNAs (miRNA, or miR) play vital roles in regulating osteogenic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs). Elucidation of the molecular mechanisms that govern BMSCs osteogenic differentiation is of paramount importance for improving the treatment of bone-related diseases. In our current study, we investigated the role of miR-23a in BMSCs osteogenesis. Our results revealed that miR-23a was significantly downregulated during osteogenic differentiation. Overexpression of miR-23a inhibited osteogenic differentiation of hBMSCs in vitro, whereas downregulation of miR-23a enhanced the process. Target prediction analysis and dual luciferase reporter assays confirmed that low-density lipoprotein (LDL)-receptor-related protein 5 (LRP5) was a direct target of miR-23a. Furthermore, knockdown of LRP5 inhibited osteogenic differentiation of hBMSCs, similar to the effect observed in upregulation miR-23a. Our data indicate that miR-23a plays an inhibitory role in osteogenic differentiation of hBMSCs, which may act by targeting LRP5.

As DNA is employed to serve as a smart building block, an increasing interest has been devoted to the development of different DNA-based machines for the specific purpose, for example, the exploration of inter- or intramolecular interaction. In the current contribution, we developed an intelligent DNA machine and its operation can be designed to execute the ultrasensitive colorimetric detection of target nucleic acids. The DNA machine consists of a hairpin probe (HP) and an assistant template (AT). Using p53 gene as the target model to trigger the molecular machine operation, cyclic nucleic acid strand displacement polymerization (CNDP) was specifically induced, leading to the DNAzyme mediated catalytic reaction for signal readout. Specifically, with the help of polymerase and nickase, one target molecule was able to drive DNA nano-mechanical devices one-by-one through the hybridization/polymerization displacement cycles, and every initiated machine continued to operate, causing the dramatic accumulation of G-quadruplex-contained products. The G-quadruplex structure after binding to hemin could act as a horseradish peroxidase (HRP)-mimicking DNAzyme and catalyzed the oxidation of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) by H2O2. As a result, an enhanced color change could be detected because of the generation of oxidation product ABTS•(+). In this way, the DNA machine has no any signal loss and enables the quantitative measurement of p53 DNA with a detection limit of 10fM, indicating great promise for unique application in biomedical research and early clinical diagnosis.

In this work, sulfur doped carbon nitride quantum dots (S-CNQDs) were prepared by one-pot copolymerization using melamine and thiourea as starting materials. The composite (g-C3N4/S-CNQDs), showing enlarged surface area, was fabricated by one-step in situ polymerization. The composites displayed much better photocatalytic activity than pristine g-C3N4 in degradation of methyl orange (MO) under UV–visible light irradiation. The removal efficiency of MO reached by 94.3% under visible light (λ ​> ​420 ​nm) illumination within 80 ​min, whereas it was nearly 100% under UV–visible light (λ ​> ​350 ​nm) irradiation within 40 ​min. The enhanced photocatalytic activity of composites is attributed to the doping of S-CNQDs, which leads to higher separation of photo-generated electron-holes, extended visible light response and more active sites. Additionally, the potential mechanism of photocatalytic degradation on MO by g-C3N4/S-CNQDs was proposed. This work presented a simple way for constructing S-CNQDs-based g-C3N4 catalyst.

Reducing the background signal and interference is an effective method for improving the sensitivity of an electrochemical immunosensor, which is greatly important for detecting tumour markers. In this study, a novel hybrid, nanoflower-like immunosensor probe was synthesised using graded copper silicate hollow spheres (CSH). A ‘close and open’ strategy was used in the immunosensor to magnify response signal. When the reaction conditions were 0.1 M PBS (pH = 7), the silicate and molybdate reaction produced a smaller signal, at which point the signal was off. When the reaction conditions were changed to 0.1 M PBS solution (containing 0.2 M HCl), MoS2 dissolved to form molybdate, while CSH-generated silicates reacted to form molybdate silicates to produce strong oxidation currents and the signal was turned on. This was the first enzyme-free electrochemical reading experiment conducted using inorganic silicate ion transduction. It had the following advantages: (1) CSH spheres with a three-dimensional hierarchical structure had a high specific surface area that allowed them to connect with more antibodies, which improved sensitivity; (2) the method was simple, the detection was fast and the background signal and interference were reduced. The immunosensor had a wide linear range from 0.1 pg mL−1 to 80 ng mL−1 and a minimum detection limit of 0.03 pg·mL−1 (S/N = 3) when detecting carcinoembryonic antigen.

A three-dimensional array of reduced graphene oxide/MoS2 @ polyaniline-layered nanosheets (denoted as rGO/MoS2 @ PANI) has a novel structure of intercalated MoS2/PANI nanosheets arrays arranged on rGO that can be used as carcinoembryonic antigen (CEA) electrochemical immunosensors (detectors). In this graded nanosheet, the PANI was embedded in the MoS2 interlayer. The MoS2/PANI nanosheets themselves limit volumetric changes when arranged as MoS2/PANI nanosheet arrays on rGO nanosheets to provide tight and sufficient heterogeneity. PANI locates on the interface itself and contains a large amount of –NH2 that can bind many antibodies. Simultaneously, we investigated the optimal amount of aniline to add. We found that these arrays had excellent film thickness and conductivity for improving CEA detection sensitivity. The tested immunosensor achieved sensitive and specific detection of CEA, with a detection limit of 0.3 pg mL−1. Under the optimal conditions, the prepared immunosensor exhibited acceptable reproducibility and selectivity and excellent stability. Satisfactory results of human serum samples indicated the potential application of the immunosensor for clinical monitoring of tumor markers.

(Liquid + liquid) equilibrium (LLE) data were determined for two ternary systems of (water + 2-propanol + ethyl butyrate) and (water + 2-propanol + n-pentyl acetate) at T = (293.15, 303.15 and 313.15) K under atmospheric pressure. The experimental data were correlated by the thermodynamic modified UNIQUAC and extended UNIQUAC models. The consistency of the experimental LLE data was further ascertained by applying Hand and Bachman equations. The extraction capability of ethyl butyrate and n-pentyl acetate was estimated by distribution coefficients and separation factors. The extraction efficiencies of ethyl butyrate and n-pentyl acetate were compared with those of other extraction agents such as isobutyl acetate, butyl acetate, butyl propionate and sec-butyl acetate. And extraction performance of ethyl butyrate and n-pentyl acetate in the extraction of 2-propanol from 2-propanol-water solutions was confirmed.

A series of novel 5α, 8α-endoperoxide steroidal hybrid derivatives containing isatin or indole substituents on the C-17 side chain were synthesized and characterized. The preliminary anti-proliferative activity of the compounds against HepG2, MCF-7, HT-29 and HeLa cell lines were investigated. Compounds 7g and 7l displayed significant anti-proliferative activity in vitro against HepG2 and Hela cells, with IC50 values lower than 8 μM. Furthermore, the biological functions of 7g were examined by flow cytometry and colony analysis. The results showed that 7g could induce HepG2 cell apoptosis, inhibited cell cycle progression, and colony growth. The studies indicated that structural modification at C-17 position could be a promising launch point for design steroidal anticancer agents.

Reduced graphene oxide (rGO)/boron nitride (BN) composite films were successfully fabricated by facile vacuum filtration and subsequent thermal treatment. Their morphology, structure and electrochemical performance were systematically characterized by field emission scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, cyclic voltammetry, galvanostatic charge/discharge and electrochemical impedance spectroscopy. Importantly, the as-prepared rGO/BN composite film with a 2 wt.% BN content as binder-free anode material for lithium ion batteries (LIBs) exhibited a high reversible capacity of 278 mAh·g−1 at a high current density of 100 mA·g−1, high rate capability, and high capacity retention over the first 200 cycles. The enhanced electrochemical performances of rGO/BN composite film are attributed to the unique structure and the synergistic effects between layered BN and graphene, which favored electrolyte penetration and buffered the volume expansion during the lithiation and delithiation process. In addition, this work not only provides a versatile strategy for fabrication of other graphene-based films, but also shows the potential promise of rGO/BN composite film for other energy storage devices. Accepted version

Molecular beacon (MB) is usually explored as a convenient probe for various bioassays. In an enzymatic polymerization-based biosensing system, primer, and MB, sometimes involving other oligonucleotides, are often required to collaboratively generate an amplified fluorescent signal to detect target molecules with high sensitivity and specificity. In the current study, a multifunctional primer-integrated MB (MP-MB) was developed to detect the p53 tumor suppressor gene. Compared with the traditional MB, our MP-MB can not only selectively identify the target of interest and signal sensitively its hybridization event, but also act as the primer during enzymatic polymerization. Specifically, hybridization of MP-MB to target p53 gene restored the fluorescence intensity and activated the pre-locked primer designed by changing the molecular configuration of MP-MB. Moreover, the p53 gene could be detected down to 1nM with a linear response range of 1×10(-9)-3×10(-7)M, and p53 gene point mutation was readily distinguished from the wild-type one. Its potential application as a primer of replication in enzymatic polymerization-based assay systems was validated by running parallel gel electrophoreses in comparison with the native counterpart of MP-MB without any chemical modification. Owning to its excellent assay characteristics, less species requirement, broad sequence diversity and preserved intrinsic bioactivity, the proof-of-concept of MP-MB exhibits a great potential in various biomedical applications.

A simplified Carba NP test (CNPt), the CNPt-direct, was evaluated for carbapenemase detection using 272 gram-negative bacteria. Compared to the Modified Hodge test, the CNPt-direct had higher sensitivity (98.2% vs. 71.6%). The simplified Carba NP is an accurate, cheap and simple test for rapid carbapenemase detection.

An electrochemical immunosensor for quantitation of carcinoembryonic antigen (CEA) based on Au-Ag/rGO@PDA nanocomposites for dual signal amplification strategy was designed. Polydopamine-coated Ag/graphene hybrids were synthesized by one-step reduction and functionalization, and the dopamine was introduced to replace some reducing agents that are harmful to organisms. Silver nanoparticles modified on the electrodes produced sensitive electrochemical redox peaks. When different amounts of protein (antigen, antibody, bovine serum protein, etc.) were adsorbed on the surface of nano-silver, the surface of nano-silver was covered. The electrochemical redox peak of silver particles decreased due to the change of the effective area of bare silver particles which could react with electrodes. In addition, CEA-antibody (anti-CEA) was immobilized into a biocompatible nanocomposite of Au nanoparticles as a conductive matrix, and CEA-antibody (anti-CEA) was combined with Ag/rGO@PDA to form a dual signal amplifying element. Under optimal condition, the linear relationship was obtained from 0.001 ng mL−1 to 80 ng mL−1 between current signal and CEA concentration with a detection limit of 0.286 pg mL−1 (signal-to-noise ratio is 3). The label-free electrochemical immunosensor has been successfully applied to human serum detection due to good selectivity, stability and reproducibility.

Hierarchical CoNiO2 polyhedral mesoporous structure using a novel hydrothermal method followed by the microwave carbon bath irradiation annealing process. The nanostructure, morphology, surface area and magnetic properties are characterized and investigated in detail. These results reveal that the regular hexagon mesoporous structures and the large specific surface area of 53.57 m3/g play an essential role in enhanced electrochemical activity. CoNiO2 modified glass carbon electrode with output power of 720 W (CNO-720/GCE) exhibits perfect electrochemical ultratrace detection toward Cu(II) with low detection limit of 3.1 nM and high sensitivity of 7.554 μA/μM under the optimized experimental conditions, and also shows the excellent repeatability, reproducibility, stability and selectivity. The improved electrochemical performance is associated with the specific hierarchical polyhedral structure, abundant mesporous channels, stable crystal surface and strong affinity toward Cu(II). Therefore, the synthesized CNO-720/GCE nanomaterials can be applied for ultratrace detection of heavy metal ions.

Mesenchymal stem cells (MSCs) can differentiate into several distinct cell types, including osteoblasts and adipocytes. The balance between osteogenic and adipogenic differentiation is disrupted in several osteogenic-related disorders, such as osteoporosis. So far, little is known about the molecular mechanisms that drive final lineage commitment of MSCs. In this study, we revealed that miR-17-5p and miR-106a have dual functions in the modulation of human adipose-derived mesenchymal stem cells (hADSCs) commitment by gain- and loss-of-function assays. They could promote adipogenesis and inhibit osteogenesis. Luciferase reporter assay, western blot and ELISA suggested BMP2 was a direct target of miR-17-5p and miR-106a. Downregulation of endogeneous BMP2 by RNA interference suppressed osteogenesis and increased adipogenesis, similar to the effect of miR-17-5p and miR-106a upregulation. Moreover, the inhibitory effects of miR-17-5p on osteogenic and adipogenic differentiation of hADSCs could be reversed by BMP2 RNA interference. In conclusion, miR-17-5p and miR-106a regulate osteogenic and adipogenic lineage commitment of hADSCs by directly targeting BMP2, and subsequently decreased osteogenic TAZ, MSX2 and Runx2, and increased adipogenic C/EBPα and PPARγ.

Sustained activation of X-box-binding protein 1 (XBP1) results in endothelial cell (EC) apoptosis and atherosclerosis development. The present study provides evidence that XBP1 mRNA splicing triggered an autophagic response in ECs by inducing autophagic vesicle formation and markers of autophagy BECLIN-1 and microtubule-associated protein 1 light chain 3β (LC3-βII). Endostatin activated autophagic gene expression through XBP1 mRNA splicing in an inositol-requiring enzyme 1α (IRE1α)-dependent manner. Knockdown of XBP1 or IRE1α by shRNA in ECs ablated endostatin-induced autophagosome formation. Importantly, data from arterial vessels from XBP1 EC conditional knock-out (XBP1eko) mice demonstrated that XBP1 deficiency in ECs reduced the basal level of LC3β expression and ablated response to endostatin. Chromatin immunoprecipitation assays further revealed that the spliced XBP1 isoform bound directly to the BECLIN-1 promoter at the region from nt −537 to −755. BECLIN-1 deficiency in ECs abolished the XBP1-induced autophagy response, whereas spliced XBP1 did not induce transcriptional activation of a truncated BECLIN-1 promoter. These results suggest that XBP1 mRNA splicing triggers an autophagic signal pathway through transcriptional regulation of BECLIN-1. Background: Apoptosis and autophagy are two closely related systems that induce cell death. Results: X-box-binding protein 1 (XBP1) mRNA splicing regulates BECLIN-1 transcriptional activation, a fundamental player in the initiation of autophagy. Conclusion: XBP1 splicing induces an autophagic response in endothelial cells. Significance: XBP1 could be used as an important pharmacological target that can regulate the autophagic machinery and endothelial cell death.

Trimercaptotriazine-functionalized polystyrene chelating resin was prepared and employed for the adsorption of Ag(I) from aqueous solution. The adsorbent was characterized according to the following techniques: Fourier transform infrared spectroscopy, elemental analysis, scanning electron microscopy and the Brunauer-Emmet-Teller method. The effects of initial Ag(I) concentration, contact time, solution pH and coexisting ions on the adsorption capacity of Ag(I) were systematically investigated. The maximum adsorption capacity of Ag(I) was up to 187.1 mg/g resin at pH 0.0 and room temperature. The kinetic experiments indicated that the adsorption rate of Ag(I) onto the chelating resin was quite fast in the first 60 min and reached adsorption equilibrium after 360 min. The adsorption process can be well described by the pseudo second-order kinetic model and the equilibrium adsorption isotherm was closely fitted by the Langmuir model. Moreover, the chelating resin could selectively adsorb more Ag(I) ions than other heavy metal ions including: Cu(II), Zn(II), Ni(II), Pb(II) and Cr(III) during competitive adsorption in the binary metal species systems, which indicated that it was a highly selective adsorbent of Ag(I) from aqueous solution.

A mesoporous silica SBA-15-supported palladium with spindle-like nitrogen donor groups, 1,4-diaza-bicyclo[2.2.2]octane, has been successfully prepared and applied for homocoupling of terminal alkynes. The catalyst exhibited very high activity for terminal alkynes carrying various substitution groups, yields ranging from 70% to 94%, with a significant advantage that air acted as the oxidant. It also showed good reusability, could be easily recovered through filtration and washing, and reused at least five times with virtually no evident loss of catalytic performance. Furthermore, it was also proved to be an effective and air-stable heterogeneous catalyst for Suzuki coupling of aryl halides (X = I, Br) with arylboronic acids. The catalyst was systematically characterized by elemental analysis, X-ray photoelectron spectroscopy, high-resolution transmission electron microscope, nitrogen physical adsorption, Brunauer–Emmett–Teller method and X-ray powder diffraction. The analyses indicated that the mesoporous structure of the materials was retained during the immobilization process.

An amine-functionalized mesoporous silica SBA-15 supported palladium catalyst was prepared and characterized. For the first time, this supported palladium has been used as an efficient phosphine-free and reusable catalyst for the cross-coupling of haloalkynes with terminal alkynes. A variety of haloalkynes and aromatic/aliphatic terminal alkynes were selectively coupled to afford unsymmetrical 1,4-disubstituted 1,3-diynes in good yields.

Al2O3 diffusion barriers of various thicknesses have been fabricated by filtered arc ion plating between the NiCrAlY coating and the O-Ti2AlNb alloy. Isothermal oxidation tests and three-point bend tests have been conducted to investigate the influence of the Al2O3 diffusion barriers on the oxidation and interfacial fracture behaviour of the coatings. The results indicate that the Al2O3 diffusion barrier defers interdiffusion and gives oxidation resistance of the NiCrAlY coatings. The thickness of the Al2O3 interlayer not only influences the oxidation behaviour but also affects the interfacial fracture properties. Additionally, thermal exposure affects the critical load in three-point bend tests.

The uniform and dense Al(2)O(3) and Al(2)O(3)/Al coatings were deposited on an orthorhombic Ti(2)AlNb alloy by filtered arc ion plating. The interfacial reactions of the Al(2)O(3)/Ti(2)AlNb and Al(2)O(3)/Al/Ti(2)AlNb specimens after vacuum annealing at 750 degrees C were studied. In the Al(2)O(3)/Ti(2)AlNb specimens, the Al(2)O(3) coating decomposed significantly due to reaction between the Al(2)O(3) coating and the O-Ti(2)AlNb substrate. In the Al(2)O(3)/Al/Ti(2)AlNb specimens, a gamma-TiAl layer and an Nb-rich zone came into being by interdiffusion between the Al layer and the O-Ti(2)AlNb substrate. The gamma-TiAl layer is chemically compatible with Al(2)O(3), with no decomposition of Al(2)O(3) being detected. No internal oxidation or oxygen and nitrogen dissolution zone was observed in the O-Ti(2)AlNb alloy. The Al(2)O(3)/Al/Ti(2)AlNb specimens exhibited excellent oxidation resistance at 750 degrees C. (C) 2010 Elsevier B. V. All rights reserved.

The transient behavior of two-phase flow and heat transfer in a channel filled with porous media was numerically studied in this paper. Based on the two-phase mixture model, numerical solutions were obtained using the Finite-Volume Method (FVM). Two methods to treat the discontinuous diffusion coefficient in the energy equation, i.e. the harmonic mean method and the “modified” Kirchhoff method were compared. It was found that the “modified” Kirchhoff method was better in dealing with the rapid change in the diffusion coefficient. Three different cases, with discrete heat flux applied at (1) the upper wall, (2) lower wall and (3) both the upper and lower walls were studied. The velocity and temperature fields for these cases were discussed. The results show that the liquid and vapor flow fields, as well as the temperature and liquid saturation fields have distinctly different features with the change in heating location. An analysis of the vapor volume fraction indicates that the largest amount of vapor with the highest vapor generation rate was for the case in which the heat flux is applied from the lower wall.

Fluid flow and heat transfer characteristics in a channel with staggered porous blocks were numerically studied in this paper. The Navier–Stokes and Brinkman–Forchheimer equations were used to model the fluid flow in the open and porous regions, respectively. Coupling of the pressure and velocity fields was resolved using the SIMPLER algorithm. The local thermal equilibrium model was adopted in the energy equation to evaluate the solid and fluid temperatures. The effect of Darcy number, Reynolds number, porous block height and width on the velocity field were studied. In addition, the effects of the above parameters as well as the thermal conductivity ratio between the porous blocks and the fluid on the local heat transfer were analyzed. The pressure drops across the channel for different cases were discussed. The results show that the flow behavior and its associated local heat transfer are sensitive to the variation of the above parameters. It is predicted by the present study that an increase in the thermal conductivity ratio between the porous blocks and the fluid results in significant enhancement of heat transfer at the locations of the porous blocks.

Zirconia supported platinum and tungstophosphoric acid (TPA) metal-acid bifunctional catalysts modified with lanthanum were prepared and tested in the reaction involving the production of branched-chain alkanes by skeletal isomerization of n -pentane. The prepared samples were characterized by XRD, FT-IR, H 2 -TPR and XPS. The catalytic performance was evaluated at 200 °C under atmospheric pressure. According to the conversion and selectivity a promotion effect of La on the activity of Pt-TPA/ZrO 2 was found and the optimal doping amount of La depended strongly on the Pt loadings. Simultaneously, cerium was also found to have the similar effect that was weaker than that of La.

Single crystalline ZnO films were grown on c-plane GaN/sapphire (0 0 0 1) substrates by molecular beam epitaxy. Cr+ ions were implanted into the ZnO films with three different doses, i.e., 1 × 1014, 5 × 1015, and 3 × 1016 cm−2. The implantation energy was 150 keV. Thermal treatment was carried out at 800 °C for 30 s in a rapid thermal annealing oven in flowing nitrogen. X-ray diffraction (XRD), atomic force microscopy, Raman measurements, transmission electron microscopy and superconducting quantum interference device were used to characterize the ZnO films. The results showed that thermal annealing relaxed the stress in the Cr+ ions implanted samples and the implantation-induced damage was partly recovered by means of the proper annealing treatment. Transmission electron microscopy measurements indicated that the first five monolayers of ZnO rotated an angle off the [0 0 0 1]-axis of the GaN in the interfacial layer. The magnetic-field dependence of magnetization of annealed ZnO:Cr showed ferromagnetic behavior at room temperature.

The polycrystalline samples of La 0.7 Pb 0.3 MnO 3 synthesized by the sol–gel method were studied by the low frequency internal friction measurements and the resistance and ac susceptibility measurements. There are two internal friction peaks at 258 and 198 K, respectively, the peak positions of which do not shift with frequency but the peak heights of which decrease with increasing frequencies. The modulus softening is evident at the corresponding temperatures. Corresponding to the two internal friction peaks, there are two resistance peaks, and a sharp rise and a following continuous decrease of ac susceptibility. It is suggested that the high temperature peaks correspond to the paramagnetic (PM) to ferromagnetic (FM) transition, while the low temperature peaks originate from the process of an anti-ferromagnetic phase (AFM) separating from the ferromagnetic matrix (phase separation) in polycrystalline materials. The peak positions of internal friction and resistance will move towards higher temperature when the sample was annealed in flowing oxygen, and the low temperature peaks become smaller.

MoS2 microspheres with nanorods were successfully synthesized by hydrothermal method at 240 °C for 24 h, employing sodium molybdate and L-cysteine as reactants. L-cysteine turned out to be served as both the sulfur source and the directing molecule in the formation of molybdenum disulfide nanostructures. The as-prepared MoS2 was characterized by X-ray power diffraction (XRD), X-ray photoelectron spectrum (XPS), field-emission scanning electron microscopy (FE-SEM) and Fourier transform infrared spectroscopy (FT-IR). FE-SEM images showed that the product was microspheres, consisting of nanorods with length of about 100 nm. The possible formation mechanism was also discussed. The results indicated that MoO2 was the metastable phase and Na2MoO4·2H2O was converted to MoS2 via MoO2.

Anelastic relaxation behavior of hydrogen atom diffusion in Ni3Al was investigated in single crystal by an inverted torsion pendulum. Two peaks appeared at about 270 K (P-0) and 387 K (P-1), which were considered to be caused by stress-induced reorientation of the H-H pairs and B-H pairs, respectively. (C) 2002 Acta Materialia Inc. Published by Elsevier Science Ltd. All rights reserved.

The internal friction and elastic modulus, together with the electrical and magnetic properties, are measured for the La 0.82 Sr 0.12 MnO 3 colossal magnetoresistance bulk materials. Two internal friction peaks and the corresponding softening of elastic modulus and two resistance peaks are observed around 276 and 154 K respectively.

Epitaxial trilayer films of La0.67Sr0.33MnO3 (LSMO)/La0.75MnO3 (L0.75MO)/La0.67Sr0.33MnO3 (LSMO) have been prepared on (0 0 1) oriented LaAlO3 substrates by dc magnetron sputtering. The structure and MR are studied. All as-deposited trilayer films exhibit a semiconductor to metal transition at temperature ranging from 116 to 185 K. The MR is also shown to be dependent on the thickness of the middle oxide layer. A maximum MR value of 32% (ΔR/R0) has been obtained at 132 K under 0.4 T magnetic field for a LSMO (300 nm)/L0.75MO (70 nm)/LSMO (300 nm) trilayer film. The MR of trilayer film prefers to that of both LSMO and L0.75MO single layer films.

The structure and properties of La0.7Pb0.3MnO3−δ (LPMO) bulk and films, which are deposited onto (001), (110) and (111) LaAlO3 (LAO) substrates using the direct current magnetron sputtering technique, are obtained. For bulk of LPMO, Tp is almost equal to Tc (252 K) and its R(T) curve has a bump in low temperature region. For films, the colossal magnetoresistance (CMR) of 28% at 155 K and in 0.5 T was observed on (001) oriented substrate under 9 Pa sputtering gas pressure and substrate temperature of 790 °C. The transport properties of the deposited films are slightly lower than that of the bulk.

MoS2 nanorods were successfully synthesized via hydrothermal method by adding sillicontungstic acid as an additive. The products were characterized by X-ray powder diffraction (XRD), X-ray photoelectron spectrum (XPS) and field-emission scanning electron microscopy (FESEM). XRD pattern result indicated that the as-prepared sample can be indexed to a mixture of hexagonal and rhombohedral phase MoS2. XPS showed that the nanorods were only composed of Mo and S with atomic ratio of 1:2. FESEM images revealed that the MoS2 rods had uniform sizes with mean diameters of about 20–50 nm and lengths of 400–500 nm. It was found that the addition of sillicontungstic acid played a crucial role in the formation of the rod-like MoS2 in our experiment. The possible formation mechanism of MoS2 nanorods is also discussed.