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Three new copper(II) and nickel(II) complexes, [Cu3L2(μ2-NO3)2(μ1,1-N3)2] (1), [Cu2L2(μ1,1-N3)2]n (2) and [Ni3L2(MeOH)2(μ2-η1:η1-CH3COO)2(μ2-η2:η0-CH3COO)2] (3), where L = 5-bromo-2-((3-methylaminopropylimino)methyl)phenolate, have been synthesized and characterized. The complexes were characterized by elemental analyses, IR, UV–Vis spectra, molar conductivity, and single crystal X-ray diffraction. X-Ray analysis indicates that the Cu ions in 1 are in square pyramidal and octahedral coordination, and the Cu ions in 2 and the Ni ions in 3 are in octahedral coordination. The molecules of the complexes are linked through hydrogen bonds and π···π interactions. The complexes were assayed for antibacterial activities against three Gram-positive bacterial strains (Bacillus subtilis, Staphylococcus aureus, and Streptococcus faecalis) and three Gram-negative bacterial strains (Escherichia coli, Pseudomonas aeruginosa, and Enterobacter cloacae) by the MTT method. [ABSTRACT FROM AUTHOR]

Steganography, also known as "invisible" communication, refers to the technique of hiding information into another medium such as video, audio, image, and text. Surface‐enhanced Raman scattering (SERS) nanotags are well suited to information encoding owing to their nanoscale dimensions, fingerprint optical spectral features, and remarkable multiplexing capability. Herein, Raman ink, fabricated by doping a new type of SERS nanotags (gap‐enhanced Raman tags, GERTs) into commercial ink, is demonstrated as security ink for multiplexing steganography. A stego‐text is written using two types of Raman ink containing different GERTs with diverse Raman signals, imaged via a confocal Raman system, and processed by the classical least squares method to extract the hidden message. The Raman ink generates distinct spectral profiles with low background from pure ink upon near‐infrared laser irradiation. A multiplexing combination of seven kinds of messages extracted from the written stego‐text is demonstrated, which adds enhanced safety and flexibility to information encoding. In addition, Raman ink exhibits good photostability and long‐term stability. Therefore, GERTs‐based Raman ink is promising for steganographic use in information security. [ABSTRACT FROM AUTHOR]

Background: Pancreatic cancer is a devastating malignancy with poor prognosis. Metformin, a classic anti-diabetes drug, seems to improve survival of pancreatic cancer patients in some studies. Methods: Cell counting kit-8 assay was used to detect the BxPC-3 and MIAPaCa-2 cell viability after treatment with gemcitabine only or with different concentrations of metformin. The methylation state and expression level of miR-663 were detected by methylation analysis and RT-PCR. Dual-luciferase reporter gene analysis, Western blot and RT-PCR were used to confirm the target of miR-663. Moreover, xenograft experiment was also performed to validate the role of metformin in chemosensitivity in vivo. Results: We found that metformin increased the chemosensitivity of pancreatic cancer cells to gemcitabine, and epithelial–mesenchymal transition (EMT) progress caused by gemcitabine was suppressed by metformin. We further explored the possible molecular mechanisms and it was demonstrated that CpG islands of miR-663 were hypomethylated and relative expression level of miR-663 was up-regulated after treatment of metformin. miR-663, an important cancer suppressor miRNA, was confirmed to increase the chemosensitivity of pancreatic cancer cells by reversing EMT directly targeted TGF-β 1. Moreover, we identified that metformin increased the chemosensitivity through up-regulating expression of miR-663. Conclusion: We demonstrated that metformin increased the chemosensitivity of pancreatic cancer cells to gemcitabine by reversing EMT through regulation DNA methylation of miR-663. [ABSTRACT FROM AUTHOR]

Surface-enhanced Raman scattering (SERS) technique has shown extraordinary features for biomedical applications. The implementation of SERS nanotags has opened a new era for bioimaging and detections. As a powerful tool, SERS nanotags provide favorable properties such as fingerprint spectrum, narrow peak linewidth, good photostability, and high spatial resolution accompanied by various rational designs of nanoparticles. They have proven as useful imaging agents for in vivo, ex vivo, and in vitro detection of cancerous cells and tissues. This tutorial provides the basic principles of SERS and SERS nanotags, including recent progress of SERS-based bioimaging applications, as well as the outlooks into the future developments toward practical clinical SERS. [ABSTRACT FROM AUTHOR]

A centipede like thiocyanate-bridged multi-nuclear copper(I/II) complex, [Cu2L(CH3OH)(NCS)3]n, derived from 2-(((2-(dimethylamino)ethyl)imino)methyl)-5-fluorophenol (HL), was prepared and characterized by elemental analysis, IR and UV–vis spectra, as well as single crystal X-ray diffraction. The Cu1 ion in the +2 oxidation state is coordinated by the tridentate Schiff base ligand in a square pyramidal geometry, with the other two sites occupied by one N atom of the thiocyanate ligand and one methanol O atom. The Cu2 ion in the +1 oxidation state is coordinated by one N and three S atoms from four thiocyanate ligands, forming a tetrahedral geometry. The CuI ions are linked by thiocyanate ligands to form a one-dimensional chain with [CuI2(μ1,3,3-NCS)2] as the repeat unit. The [CuIIL(CH3OH)] moieties are linked to the chain through thiocyanate ligands. The complex has remarkable inhibitory activity on Jack bean urease with an IC50 value of 1.3 μmol L–1. [ABSTRACT FROM AUTHOR]

Abstract The lower-strength defect of inorganic phosphate adhesive had been definitely improved by self-generating multiple high-temperature resistant phases. Compared to our previous product, the best bonding performance of this novel adhesive for mullite was increased by 270%, which was close to some popular preceramic polymer-based adhesives. The apparent shear strength at room temperature was up to 33.1 MPa after calcination at 900 °C, while the high-temperature strength researched 23.3 MPa at 900 °C and maintained above 17 MPa from 700° to 1200 °C. The reinforced effect of adhesive owed to the introduction of various Cu-based intermetallics, the premature generation of Al 4 B 2 O 18 at 900 °C, and the structure optimizing through the oxidization of Si and B 4 C. Besides, the novel adhesive displayed good resistance to thermal-shock, especially for air-cooling test. After 15 thermal cycles in air, the residual strength of 1300 °C-calcined joints was still above 13 MPa (~40%). [ABSTRACT FROM AUTHOR]

Pancreatic cancer is a common malignant tumor worldwide. Extensive studies have been conducted on the functional role of long noncoding RNAs in pancreatic cancer. In this study, long intergenic nonprotein coding RNA 173 (LINC00173) was highly expressed in pancreatic cancer tissues. In vitro functional experiments showed that LINC00173 overexpression inhibited the proliferation and invasion of pancreatic cancer cells and promoted cell apoptosis in MIA PaCa-2 and PANC-1 cells. RNA sequencing analysis and Western blot assays demonstrated that LINC00173 reduced the expression of sphingosine kinase 1 (SPHK1) and then inhibited the protein expression of activated phospho-protein kinase B (AKT) and NF-κB. In vivo functional assays also revealed that LINC00173 inhibited the growth of pancreatic cancer xenografts, repressed cell proliferation, promoted cell apoptosis, and inhibited SPHK1 expression. The combined results of this study indicate that LINC00173 inhibits pancreatic cancer progression by repressing SPHK1 expression. Improving LINC00173 may represent a therapeutic strategy for pancreatic cancer in the future. [ABSTRACT FROM AUTHOR]

Abstract Mullite whiskers were successfully in-situ synthesized in phosphate-based adhesive by taking Si and Al(OH) 3 as reaction sources and AlF 3 as the catalytic initiator. After calcination at 1300 °C, both strength and toughness of whisker-growth adhesive got greatly improved, which were increased by 75% and 156%, respectively. The bonding strength was enhanced to 23.8 MPa, which was close to some hot preceramic polymer-based adhesives. An approximate yield stage appeared on its corresponding loading-curve, showing unprecedented toughness and high damage capacity. In addition, the residual rate of bonding strength still maintained 63% after 20 thermal cycles (room temperature-1300 °C). [ABSTRACT FROM AUTHOR]

• Tree species diversity decreased standing biomass C stock via the dominant tree biomass C stock. • Tree species diversity enhanced the C and N stocks in stand litter mainly via affecting the proportion of conifer. • Tree species diversity enhanced the soil organic C and N stocks via increasing their stable factions. • Tree species diversity can elevate the stabilities of soil organic C and N stocks in the secondary forests. Carbon (C) and nitrogen (N) stocks are important for food security and mitigation of climate change, also could be likely affected by tree diversity. However, a detailed evaluation of the relationships between tree species diversity and stand biomass C (AGC), and the C and N stocks of stand litter and soil is still scant, especially in secondary forests. Thus, we assessed the associations between tree species diversity (i.e., Shannon-Wiener index) and the AGC stock, the C and N stocks in stand litter and soil [soil organic carbon (SOC), N, microbial biomass fractions (MBC and MBN), heavy fractions (HFOC and HFON) and mineral associated factions (MAOC and MAON)] at the plot level (25 m × 25 m) in mature secondary forests in subtropical China. We also used the structural equation model (SEM) to explore the underlying mechnism by which tree diversity drives the AGC stock and the C and N stocks in stand litter and soil. We found that the tree species diversity decreased AGC stock via the dominant tree biomass C stock. However, the tree species diversity enhanced the C and N stocks in stand litter mainly via affecting conifer proportion, and the SOC and N stocks at the depth of 0–40 cm via increasing their stable factions (i.e., heavy fractions and mineral associated factions). We also observed the tree species diversity had positive effects on the stocks of MBC, HFOC and HFON in soil epipedon, and had non-significant effects on the stocks of MBN, MAOC and MAON. Our results revealed that tree species diversity can elevate the soil C and N stocks and their stability in the subtropical secondary forests of China. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) is a prevalent problem worldwide. Chemotherapy, especially cisplatin (CDDP)-based systemic chemotherapy, is the best option for advanced liver cancer. However, CDDP resistance is becoming common and hindering the clinical application of CDDP. Meanwhile, no consensus has been reached regarding the chemotherapeutic use of vasohibin 2 (VASH2), which promotes the angiogenesis and proliferation of cancer cells. In this work, a tissue microarray was used to observe VASH2 and its possible role in cancer treatment. Results showed that VASH2 was highly expressed in HCC tissues and was significantly correlated with cancer differentiation. To further investigate the efficacy and mechanism of the combination of VASH2 with anti-cancer drugs in liver cancer cells, we stably built VASH2 overexpression and knockdown cell lines. We found that VASH2 can influence the CDDP sensitivity and that the cell overexpression of VASH2 had a higher cell viability and lower apoptosis rate after CDDP exposure. We also observed that VASH2 overexpression downregulated wild-type p53, as well as suppressed the expression of the pro-apoptotic protein BCL2-associated X protein (Bax) and cleaved caspase-3 (CC-3) after treatment by CDDP. Conversely, the knockdown of VASH2 significantly inhibited these effects. In an in vivo chemosensitivity study, nude mice were subcutaneously injected with tumor cells and received CDDP treatment through intraperitoneal administration every 3 days. We found that VASH2 knockdown markedly limited the tumor growth and enhanced the CDDP toxicity and apoptosis of tumor cells. Western blot analysis revealed that tumor cells with downregulated VASH2 had a higher expression of wild-type p53, Bax, and CC-3 than control cells. Overall, our results indicated the novel roles of VASH2 in the chemoresistance of hepatocarcinoma cells to CDDP and suggested that VASH2 may be a promising anticancer target. [ABSTRACT FROM AUTHOR]

Pancreatic cancer is a digestive system tumour disease with a notably poor prognosis and a 5-year survival rate of less than 10 %. In recent years, peptide drugs have shown great clinical value in antitumour applications. We aim to identify differentially expressed peptides by using peptidomics techniques to explore the mechanisms involved in the development and pathology of pancreatic cancer. We performed peptidomic analysis of pancreatic cancer and paired paracancerous tissues by using ITRAQ labelling technology and conducted in-depth bioinformatics analysis and functional studies on differentially expressed peptides. A total of 2,881 peptides were identified, of which 133 were differentially expressed (116 were upregulated and 17 were downregulated). By using GO analysis, the differentially expressed peptides were found to be closely related to the tumour microenvironment and extracellular matrix. KEGG enrichment analysis revealed that precursor proteins were closely related to the T2DM and RAS signalling pathways. The endogenous peptide P1DG can significantly inhibit the proliferation, migration and invasion of pancreatic cancer cells. P1DG and its precursor GAPDH may be closely related to the proliferation, migration and invasion of pancreatic cancer. Peptidomics can aid in understanding the pathogenesis of pancreatic cancer more comprehensively. [ABSTRACT FROM AUTHOR]