The authors describe a silicon nanoparticle-based fluorometric method for sensitive and selective detection of Cu2+. It is based on the catalytic action of Cu2+ on the oxidation of cysteine (Cys) by oxygen to form cystine and the by-product H2O2. The generated H2O2 is catalytically decomposed by Cu2+ to generate hydroxyl radicals which oxidize and destroy the surface of SiNPs. As a result, the blue fluorescence of the SiNPs is quenched. The method has excellent selectivity due to the dual catalytic effects of Cu2+, which is much better than most previously reported nanomaterial-based assays for Cu2+. Under the optimal conditions, the method has low detection limit (29 nM) and a linear response in a concentration range from 0.05 mu M to 15 mu M. The method has been successfully applied to the determination of Cu2+ in spiked real water samples, and the results agreed well with those obtained by the Chinese National Standard method (GB/T 7475-1987; AAS).

Hydrazine (N2H4) is widely used in industry but also very toxic. Herein, we describe the preparation of a "naked-eye" colorimetric and ratiometric fluorescent probe (DH), bearing alpha,beta-unsaturation carbonyl group as a recognition site, and employ it for the excited-state intramolecular proton transfer based (ESIPT-based) detection of N2H4. The probe can detect N2H4 by colorimetric and ratiometric fluorescence dual signals with high sensitivity and selectivity; the detection limit of N2H4 was 0.063 mu M (2.01 ppb), which was far below the safety level (10 ppb) stated by the U.S. Environmental Protection Agency (EPA). It enables "naked-eye" detection for hydrazine determination in aqueous solution. More importantly, we successfully applied DH to detect N2H4 in real water samples, indicating its potential utility for N2H4 sensing in environmental samples.

Rapid capture and selective visualization of hydrogen sulfide (H2S) in living systems has remained challenging. In this work, by employing ortho-aldehyde assisted thiolysis of 2,4-dinitrophenyl (DNP) ether approach and utilizing the dicyanomethylene-4H-chromene as the fluorophore, we developed a new fluorescent probe (E)-2-(2-(4-(2,4-dinitrophenoxy)-3-formylstyryl)-4H-chromen-4-ylidene) malo- nonitrile (2-CHO-OH) for this purpose with improved recognition performances. Probe 2-CHO-OH showed the advantage of quick reaction (8 min) with H2S, resulting in a strong near-infrared fluorescence emission (32-fold enhancement) and large Stokes shift (137 nm). More importantly, the probe could highly selectively detect H2S from other biological related species including cysteine, homocysteine and glutathione with distinct dual colorimetric and fluorescent signal changes. The detection limit of H2S was estimated as 8.3 x 10(-8) M, which was much lower than the intracellular concentration. Thanks to these unique features, 2-CHO-OH has been successfully applied for NIR fluorescence imaging of both the exogenous and endogenous H2S in living cells, demonstrating its value of practical application in biology. (C) 2017 Elsevier B.V. All rights reserved.

BACKGROUND: Keshan disease (KD) is an endemic cardiomyopathy in China. The etiology of KD is still under debate and there is no effective approach to preventing and curing this disease. Young women of child-bearing age are the most frequent victims in rural areas. The aim of this study was to determine the differences between molecular pathogenic mechanisms in male and female KD sufferers.; METHODS: We extracted RNA from the peripheral blood mononuclear cells of KD patients (12 women and 4 men) and controls (12 women and 4 men). Then the isolated RNA was amplified, labeled and hybridized to Agilent human 4*44k whole genome microarrays. Gene expression was examined using oligonucleotide microarray analysis. A quantitative polymerase chain reaction assay was also performed to validate our microarray results.; RESULTS: Among the genes differentially expressed in female KD patients we identified: HLA-DOA, HLA-DRA, and HLA-DQA1 associated with spontaneous autoimmunity; BMP5 and BMP7, involved in cardiomyocyte differentiation defect; and ADAMTS 8, CCL23, and TNFSF15, implicated in anti-angiogenic activities. These genes are involved in the canonical pathways and networks recognized for the female KD sufferers and might be related to the pathogenic mechanism of KD.; CONCLUSION: Our results might help to explain the higher susceptibility of women to this disease.=20

Alkaline phosphatase (ALP) is a non-specific phosphate monoesterase and often regarded as an important biomarker of hypothyroidism and hepatobiliary diseases in medical diagnosis. In-situ detection of endogenous ALP and exploration of the distribution of ALP in cells are of great importance for the diagnosis of diseases associated with ALP. In this work, we designed and synthesized an aggregation-induced emission (AIE) fluorescent probe, (E)-2-(((9H-fluoren-9-ylidene) hydrazono)methyl)phenyl dihydrogen phosphate (FAS-P), that can respond to ALP with a remarkable large Stokes shift ( > 200 nm) based on excited state intramolecular proton transfer (ESIPT) mechanism. The probe FAS-P has high selectivity and sensitivity to the detection of ALP. And there is a linear relationship between the fluorescence intensity of FAS-P and ALP activity in the range of 1-100 U L-1, the limit of detection (LOD) is as low as 0.6 U L-1. More importantly, we successfully applied FAS-P to detect ALP in living cells and the monitoring of ALP in real time.

We aimed to verify the levels of IGFBP2 and SOCS3 in cartilage and chondrocytes of Kashin-Beck disease (KBD) patients and the effects of different selenium concentrations on the protein expression levels. Chondrocytes were cultured with sodium selenite in vitro. Immunohistochemistry and western blotting were used to verify the protein expressions. IGFBP2 and SOCS3 were up-regulated in KBD chondrocytes and decreased with increasing selenium concentrations. IGFBP2 expressed highest in the middle zone of KBD cartilage, SOCS3 expressed higher in the middle and deep zone. IGFBP2 and SOCS3 may be the biomarkers for KBD diagnosis and evaluating the effect of selenium supplement.