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A sensitive detection method combined with an effective on-line concentration may improve the analytical performance of a paper-based analytical device (PAD), and its merits of low cost and portability in POCT are fully demonstrated. Here, a sensitive PAD system with chemiluminescence (CL) detection and electrokinetic preconcentration was introduced, and the performance was demonstrated by the detection of hemin. A commercially available low cost and miniaturized optical detection module was used for the CL detection. Firstly, hemin was stacked on a simple paper fluidic channel based on field amplified stacking (FAS), and then a CL reagent (luminol-H2O2) was loaded on the stacked band to initiate the CL reaction. The photons were directly detected using the detection module. With optimization of the background electrolyte (BGE), voltage and CL reagent, a limit of detection (LOD) of 0.58 nM for hemin was obtained with a linear range of 1-1000 nM (R2 = 0.995). With FAS, the signal intensity was about 13-fold enhanced. This PAD also exhibited satisfactory selectivity over possible interfering components at a 104 times higher concentration. The applicability of the PAD was demonstrated by the detection of hemin from iron supplements and human serum samples. With total manual operation, recovery rates of 84.8-115.6% were obtained with an RSD of less than 14.3%. With the introduction of the optical detection model, and together with FAS, both the LOD and dynamic range of this PAD were effectively improved.

Oxidative stress and apoptosis serve an important role in the development of pressure overload-induced cardiac remodelling. Carnosic acid (CA) has been found to exert antioxidant and anti-apoptotic effects. The present study investigated the underlying mechanism of CA protection and whether this effect was exerted against pressure overload-induced cardiac remodelling. Aortic banding (AB) surgery was performed to induce cardiac remodelling. Mice were randomly divided into four groups (n=15/group): i) Sham + vehicle; ii) sham + CA; iii) AB + vehicle; and iv) AB + CA. After 2 days of AB, 50 mg kg CA was administered orally for 12 days. Echocardiography, histological analysis and molecular biochemistry techniques were performed to evaluate the roles of CA. CA treatment decreased cardiac hypertrophy, fibrosis, oxidative stress and apoptosis in mice challenged with pressure overload. CA also decreased the cross-sectional area of cardiomyocytes and the mRNA and protein expression levels of hypertrophic markers. Furthermore, CA treatment decreased collagen deposition, α-smooth muscle actin expression and the mRNA and protein expression of various fibrotic markers. Additionally, CA reversed the AB-mediated increase in NAPDH oxidase (NOX) 2, NOX4 and 4-hydroxynonenal levels. The number of apoptotic cells was decreased following CA treatment following under conditions of pressure overload. CA also suppressed the activation of AKT and glycogen synthase kinase 3 β (GSK3β) in mice challenged with AB. The present results suggested that CA could inhibit pressure overload-induced cardiac hypertrophy and fibrosis by suppressing the AKT/GSK3β/NOX4 signalling pathway. Therefore, CA may be a promising therapy for cardiac remodelling.

Wetlands are hot spots for particulate organic matter (POM) supply into rivers, which link the land-ocean transfer in the global carbon cycle. However, the source, composition, and seasonal variability of POM carried by wetland-draining rivers are poorly constrained. Here we combine bulk and source-specific biomarker analyses to investigate the fluvial POM biogeochemistry of the Black and White Rivers draining from the Zoige wetland. We find that POM was dominated by terrestrial organic matter including high-molecular-weight (HMW) lipids, branched glycerol dialkyl glycerol tetraethers, and lignin phenols. However, fluvial POM was rich in HMW lipids and poor in lignin phenols compared to the catchment soils, possibly due to hydrodynamic sorting and dissolution processes. While lignin phenol concentrations were higher in the wet season, HMW lipid concentrations were lower. Additionally, lignin phenols increased with total suspended solids, while HMW lipids decrease. These contrasts imply an enhanced input of lignin-rich particles from soil surface layers in the wet season, diluting HMW lipids. Compared with that in other rivers around the world with a higher forest coverage in the catchment, POM in the Black and White Rivers draining grass-dominated wetlands had a much higher ratio of HMW fatty acids to lignin phenols. Our results represent a benchmark study highlighting compositional characteristics of fluvial POM exported from the Zoige wetland and the divergent behavior of molecular components during fluvial transfer. Such information is vital for assessing future changes in the Zoige wetland, given its high vulnerability to climatic and land use changes.

Charged species can be effectively stacked on paper-based analytical device (PAD) taking advantage of ion concentration polarization (ICP) effect. Protein, as ampholyte species, could also be stacked using this effect to improve its detection sensitivity. In this work, a protein detection method was proposed based on online ICP stacking and successfully used for the detection of total protein from urine samples. We showed that proteins from physiological samples can be directly and repeatedly loaded onto the depletion region of the ICP interface established by a piece of cation exchange membrane on a paper fluidic channel, and the protein content can be cumulatively stacked as a narrow band as visually observed by smartphone camera. Colorimetric detection of model protein (phyco) showed that at least 60-fold preconcentration could be achieved with this method. With post-staining of the stacked albumin from artificial urine, a linear response in the diagnostic meaningful range of 50–350 mg/L (R2 = 0.994) was achieved. Total protein from clinical urine samples was detected, and the recovery rate was found in the range of 93–108%, and the RSD was less than 11%. Comparative assays showed no significant difference between the results of this and that of the clinical method. This paper demonstrated the feasibility of online stacking and sensitive detection of proteins from physiological samples using PAD-ICP platform.

The inhibitory effect of resveratrol on the growth of gastric cancer cells through downregulation of the Wnt/β-catenin signaling pathway were studied. First we determined the effective concentration of resveratrol on the growth and proliferation of MGC-803 gastric cancer cells. Methylthiazolyl tetrazolium assay showed that resveratrol significantly inhibited the proliferation of MGC-803 cells in a dose-dependent manner. Resveratrol induced apoptotic morphological changes in MGC-803 cells. Reverse transcription-polymerase chain reaction and western blot analysis showed that resveratrol downregulated the expression of three important components of the Wnt signaling pathway, β-catenin, c-myc, and cyclin D1, at the mRNA and protein levels. Overall, resveratrol inhibits the growth of MGC-803 cells by inhibiting the Wnt signaling pathway. This study provides a new idea and direction for the antitumor mechanism of resveratrol.

Ion concentration polarization (ICP) effect is an effective preconcentration method for charged species in microfluidic systems. In recent years, ICP has also been introduced in paper-based analytical device (PAD) to improve the detection sensitivity. In this paper, a simple and cheap ICP interface was introduced in PAD by using commercial available ion exchange membrane (IEM) that is commonly used in industry. Significant ICP effect was observed by placing the IEM directly on a wetted paper fluidic channel, and electrokinetic stacking of both anion and cation probes was demonstrated with cation exchange membrane (CEM) and anion exchange membrane (AEM), respectively. Simply based on LED illumination and smart phone fluorescent imaging, about 10-fold signal improvement, was achieved for negatively charged fluorescent probes of fluorescein sodium and FITC-BSA with CEM, and 50-fold signal improvement was achieved for positively charged fluorescent probe of rhodamine 6G with AEM. The performance of this PAD was investigated with fluorescein sodium and rhodamine 6G, and the limits of detection of 0.34 and 0.011 μmol L−1 were achieved, respectively. This method provides a cost-effective route for improving the detection sensitivity of charged species on PAD taking advantage of ICP effect.

Electrokinetic stacking (ES) is effective for improving sensitivity of paper-based analytical device (PAD) for charged analytes. In this paper, we successfully demonstrated ES of electrically neutral analytes on PAD, and the performance was characterized by smartphone-based colorimetry and fluorescence. Firstly, SDS from cathode reservoir stacked as a micelle band on an open paper fluidic channel by ES, and the target analyte was swept by the micelle. Meanwhile, the probes at the other side were carried by electroosmotic flow (EOF). Eventually, neutral components preloaded on the channel were concentrated as the narrow stacking band. Taking the rhodamine B as a probe, the effects of EOF, background electrolyte concentration and anionic surfactant concentration were investigated. Fluorescence detection of rhodamine B and colorimetric analysis of Sudan III demonstrated the sensitivity enhanced and its potential for the semi-quantitative test. Under the optimized conditions, fluorescence detection limit of 50 nM of rhodamine B was achieved with a linear range of 1.0–10 μM (R2 = 0.99). The colorimetric detection limit for Sudan III was 5.2 μM and the linear range was 5–40 μM (R2= 0.99). Compared with direct analysis without stacking, the signal levels of rhodamine B and Sudan III were increased by 30-fold and 6-fold, respectively. This study showed that with ES, sensitive and rapid PAD detection of electrically neutral analytes could be achieved.

A novel energetic cuprous azide complex with the formula of [Cu2(dmpyz)(N3)2] n (1) (dmpyz: 2,5-dimethylpyrazine) has been synthesized through hydrothermal method by utilizing the reducibility of H3PO3 and structurally characterized by X-ray single crystal diffraction method. Single crystal X-ray diffraction analysis reveals complex (1) featuring a two-dimensional layer structure constructed from copper(I) atoms bridged by azide anion and further connected by pyrazine ligand to form a 3D network. The result of catalysis research reveals it can promote the burning rate of main component of rocket propellants.

With the increasing use of nano-SiO2and nano-kaolinite, it is imperative to investigate their effect on the transport of aqueous contaminants. In this study, the extent and reversibility of sorption of AT on nano-SiO2and nano-kaolinite were examined using batch sorption experiments. Influence of ionic strength, pH and temperature was investigated. Sorption data were well fitted with Freundlich models. The sorption capacities were larger at low ionc strengths and low pHs. Nano-particle aggregate size is an important factor for the pH influencing process, which increase as the pH approach pHzpc. The sorption of AT on the two nano-particles is spontaneous.

Introduction: Recently, two studies revealed that MET amplification was associated with secondary epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) resistance in non-small cell lung cancer (NSCLC) patients. But it remains uncertain whether MET amplification could be related to primary TKI resistance in NSCLC because of limited data. Materials and Methods: MET gene dosage of the tumor tissues from 208 NSCLC patients was investigated by real time quantitative polymerase chain reaction and compared with molecular and clinical features, including EGFR mutations, KRAS mutations, EGFR gene copy numbers, and patient survivals. Three copies were used as the cutoff. Among them, 25 patients were also evaluable for EGFR TKI responsiveness. Results: The proportion of high MET gene dosage was 10.58% (22/208) with higher incidence in squamous cell carcinoma (11.86%) and smokers (16.18%), although the differences with adenocarcinoma and nonsmokers were nonsignificant. Coexisting EGFR mutations were identified, and the incidence (8.54%) was similar to wild type (12.0%). High MET gene dosage was significantly associated with higher tumor stage (stage I + II versus stage III + IV; p = 0.0254) and prior chemotherapy for stage III + IV adenocarcinoma patients (35.71% versus 7.41%; p = 0.0145) but not correlated with primary TKI resistance. Among the 155 surgically resectable patients (stage I to IIIA), high MET gene dosage was significantly associated with shorter median survival (21.0 months versus 47.1 months; p = 0.042) by univariate analysis. Conclusions: High MET gene dosage was not related to primary TKI resistance and the incidence was increased after chemotherapy, suggesting high MET gene dosage may also be related to chemotherapy resistance.

An energetic cuprous azide complex, [Cu2(2apyz)(N3)2] n (1) (2apyz = 2-aminopyrazine), has been synthesized through hydrothermal method by utilizing the reducibility of H3PO3 and structurally characterized by single-crystal X-ray diffraction. Complex 1 has a 2-D layer structure constructed from copper(I) bridged by azide and pyrazine. Catalysis research shows 1 can promote the burning rate of the main component of rocket propellant.

A coordination polymer, [Co(2-mpac)2(4,4′-bpy)·(4,4′-bpy)] n (2-mpac: 5-methyl-2-pyrazinecarboxylic acid; 4,4′-bpy: 4,4′-bipyridine), has been synthesized through hydrothermal synthesis and structurally characterized by X-ray single crystal diffraction. Single crystal X-ray diffraction analysis reveals a 3-D network featuring a 1-D tunnel filled with 4,4′-bpy molecules. Elemental analysis, IR, thermogravimetric analysis, and magnetic properties are presented.

Utilizing Co(2-mpac)2(H2O)2 as molecular building block, a coordination polymer, [Co2(2-mpac)4(4,4′-bpy) · 2H2O] n (1) (2-mpac = 5-methyl-2-pyrazinecarboxylic acid; 4,4′-bpy = 4,4′-bipyridine), was synthesized and structurally characterized by X-ray single crystal diffraction. Elemental analysis, infrared, and magnetism are presented. Variable temperature magnetic susceptibility measurements exhibit weak antiferromagnetic interaction between Co centers in 1.

By microwave wet digestion procedure with HNO3/H2O2 to prepare samples, the mineral elements in Crocus sativus L. were completely analyzed by inductively coupled plasma optical emission spectrometer (ICP-OES). The results showed there were 17 mineral elements in Crocus sativus L., which were Na, K, S, Mg, P, Si, Ca, Fe, Al, Ti, Zn, Mn, B, Sr, Cu, Ba and Cr. The RSD of the determining result was between 0.75% and 9.49%. The mass fraction of some macroelements of the human body in Crocus sativus L., such as Na, K, S, Mg, P, Ca et al, were 0.56%, 0.54%, 0.44%, 0.41%, 0.31% and 0.23%, respectively. The contents of some necessary microelements, for example Fe, Zn, Cu and Cr, were 43.4, 1.24, 0.35, 0.10 mg/100g, respectively. The contents of those elements such as Si, Mn and B, which may be necessary to the human body, were 275.1, 1.07, 0.51 mg/100g. There has no some heavy metals such Cd, Pb, Hg, and As in Crocus sativus L.

An anaplastic thyroid cancer cell line, Thena, was recently established in our laboratory following radical thyroidectomy of a patient with anaplastic thyroid cancer. Microscopically, Thena cells were spindle-shaped or small round cells. Thena cells were reactive with cytokeratin AE1/AE3 antibodies, epithelial membrane antigen, interleukin (IL)-6, epithelial growth factor receptor, transforming growth factor (TGF)-alpha, vascular endothelial growth factor, and vimentin. Thena cells secreted high levels of IL-6, leukemia inhibitor factor (LIF), tumor necrosis factor (TNF)-alpha, and TGF-beta1 in the culture supernatants, as determined by enzyme-linked immunosorbent assay. When subcutaneously injected with Thena cells, athymic nude mice developed tumor masses in the skin within 2 weeks. Furthermore, Thena cells induced cachexia in these tumor-bearing mice. High levels of human IL-6, LIF and TGF-beta1 were detected in the mouse sera. To our knowledge, the Thena cell line is the first thyroid cancer cell line reported to induce cachexia in nude mice. This cachectic animal model is worthy of further study to explore the treatment of thyroid cancer-induced cachexia.

In the title compound, {[Cu(II)Cu(I) (2)(C(5)H(3)N(2)O(2))(2)(CN)(2)(H(2)O)(2)]·2H(2)O}(n), the Cu(II) atom lies on an inversion centre and is octa-hedrally coordinated by two N atoms and two O atoms from opposing pyrazine-2-carboxyl-ate (2-pac) ligands and two water O atoms. The Cu(I) atom has a triangular geometry, coordinated by one N atom and one C atom from two bridging cyanide ligands, and another N atom from the 2-pac ligand. The three-dimensional structure features a succession of two-dimensional sheets containing [Cu(CN)](n) chains linked by Cu(2-pac)(2)(H(2)O)(2) groups. The coordinated and free water mol-ecules are involved in an extended three-dimensional hydrogen-bond network with the 2-pac ligands.

In the title complex, [Zn(C6H5N2O2)2(H2O)2], the Zn2+ cation lies on an inversion centre and the coordination geometry is distorted octahedral, with two N atoms and two O atoms from the 5-methylpyrazine-2-carboxylate ligand in the equatorial plane. The two remaining coordination sites are occupied by two water molecules. The crystal structure is stabilized by a network of O—H...O hydrogen-bonding interactions, forming a two-dimensional supramolecular structure.

We have measured the cross-section ratios of helium induced by Cq+ and Oq+ (q = 1?4) in an energy range from 20 keV/amu to 500 keV/amu, and obtained the two-dimensional spectra by employing the coincidence method combined with the MPA-3 data acquisition system. Hence, we obtain the ratios of total single-ionization cross-sections (SI, SC, SLSI, and DLSI), total double-ionization cross-sections (DI, DC, TI, SLDI, and DLDI) and cross-sections of every process (SI, SC, SLSI, DLSI, DI, DC, TI, SLDI, and DLDI), which induce the single-ionization and double-ionization, to the total cross sections respectively. The competitive relations between the reaction-channels and the experimental data law of each reaction-channel are revealed explicitly, and the qualitative explanations involved in those results are also presented accordingly.

In the neutral title complex, [Fe(C(6)H(5)N(2)O(2))(2)(H(2)O)(2)], the coordination geometry aound the Fe(II) atom, which lies on an inversion centre, is distorted octa-hedral comprising two N atoms and two O atoms from two 5-methyl-pyrazine-2-carboxyl-ate ligands, and two water mol-ecules. The crystal structure is stabilized by a network of O-H⋯O hydrogen bonds, resulting in a two-dimensional supra-molecular structure.