A near-infrared fluorescence dye for sensitive detection of hydrogen sulfide in serum

Cy-Cl, a cationic near-infrared cyanine dye, readily reacts with hydrogen sulfide (H2S) via nucleophilic thiolation to give dose-dependent ‘turn-off’ fluorescence and colorimetric read-out, allowing selective detection of low levels of H2S in serum and imaging of mitochondrial H2S in living cells.This work was supported by Grants from NSF China 21272196, 973 Program 2013CB933901, NFFTBS (J1210014), the National Science Foundation of Fujian Province (2011J06004), and a open project grant from State Key Laboratory of C hemo/biosensing and Chemometrics (2012002); Dr. J. Han was supported by Grants from NSF China 31221065, 91029304, 81061160512 and 973 Program 2009CB522200

Traceless protein delivery with an efficient recyclable nanocarrier

NSF China [21272196, 21072162, 31221065, 91029304, 81061160512]; Fundamental Research Funds for the Central Universities [2011121020]; 973 program [2009CB522200]Intracellular delivery is a prerequisite for the efficacy of many pharmaceutical proteins. Herein, vitamin B-6 (pyridoxal-5'-phosphate, PLP) functionalized calcium phosphate (CP) is used as the bio-recyclable nanocarrier for delivery of proteins into cells. Proteins could be loaded on/released from PLP-CP via formation/hydrolysis of pH sensitive aldimine bridging lysine and surface-displayed PLP. The loaded proteins could be delivered into the cytosol of HeLa, HepG2 and L929 cells where the carrier could be metabolized into endogenous metabolites of Ca2+, HPO42-, and vitamin B-6. PLP-CP mediated cell transduction is 10-40 folds more efficient than TAT which is a widely used cell penetrating peptide, demonstrating the utility of PLP-CP as the traceless platform for high-efficiency delivery of proteins into mammalian cells

The CEV

The constant elasticity of variance (CEV) model is used to describe the price of the risky asset. Maximizing the expected utility relating to the Hamilton-Jacobi-Bellman (HJB) equation which describes the optimal investment strategies, we obtain a partial differential equation. Applying the Legendre transform, we transform the equation into a dual problem and obtain an approximation solution and an optimal investment strategies for the exponential utility function

A highly sensitive fluorogenic chemodosimeter for rapid visual detection of phosgene

NSFC [21072162, 20802060]; Natural Science Foundation of Fujian Province of China [2011J06004]; Fundamental Research Funds for the Central Universities [2011121020]; NEFTBS [J1030415]A highly sensitive chemodosimeter was identified from a panel of rhodamine derivatives for rapid and visual detection of phosgene with a detection limit of 50 nM triphosgene. Visual detection of gaseous phosgene with chemodosimeter absorbed paper strips was demonstrated

Products and Mechanistic Investigations on the Reactions of Hydrazines with Ozone in Gas-Phase

The toxic transformation products of hydrazines are of great concern. These products’ properties combined with their formation mechanisms are needed to assess their potential environmental and human impacts. In this study, the gas-phase reaction of hydrazine (N2H4), monomethyldrazine (MMH) and unsymmetrical dimethyhydrazine (UDMH) with O3 have been studied at varying reactant ratios, both in the presence and absence of a radical trap. Gas chromatography-mass spectroscopy (GC-MS) has been implied to follow reactant consumption and product formation. Apart from the reported products detected by Fourier transform infrared spectroscopy (FT-IR), the newly found compounds (hydrazones, formamides, dimethylamine, 1,1,4,4-tetramethyl-1,2-tetrazene,dimethylamino-acetonitrile, N2, H2O, et al.) are identified by GC-MS. The relative yields of the organic products vary considerably at different O3/MMH or UDMH ratios. UDMH and MMH are confirmed as high potential precursors of N-nitrosodimethylamine (NDMA). The presence of hydroxyl radicals (HO·) hinders NDMA formation in MMH-O3 system. Meanwhile, it increases NDMA formation in UDMH-O3 system. The suggested reaction mechanisms which account for the observed products are discussed

Life Cycle Exposure to Cyhalofop-Butyl Induced Reproductive Toxicity in Zebrafish

Cyhalofop-butyl (CyB) is a herbicide widely used in paddy fields that may transfer to aquatic ecosystems and cause harm to aquatic organisms. In this study, zebrafish (Danio rerio) were exposed to CyB at environmental concentrations (0.1, 1 and 10 µg/L) throughout their adult life cycle, from embryo to sexual maturity. The effects of CyB on zebrafish growth and reproduction were studied. It was found that female spawning was inhibited, and adult male fertility decreased. In addition, we examined the expression of sex steroid hormones and genes related to the hypothalamus–pituitary–gonad–liver (HPGL) axis. After 150 days of exposure, the hormone balance in zebrafish was disturbed, and the concentrations of 17β-estradiol (E2) and vitellogenin (VTG) were decreased. Changes in sex hormone were regulated by the expression of genes related to the HPGL axis. These results confirmed that long-term exposure to CyB at environmental concentrations can damage the reproductive capacity of zebrafish by disrupting the transcription of genes related to the HPGL axis. Overall, these data may provide a new understanding of the reproductive toxicity of long-term exposure to CyB in zebrafish parents and offspring

Cytosolic delivery of proteins mediated by aldehyde-displaying silica nanoparticles with pH-responsive characteristics

Natural Science Foundation of Fujian Province [2011J06004]; Fundamental Research Funds for the Central Universities [2011121020]; NSF China [21072162, 30830092, 30921005, 91029304, 81061160512]; 973 program [2009CB522200]Synthetic carriers that enable site-specific intracellular delivery of proteins are valuable in many biomedical applications. Aldehyde-displaying silica nanoparticles (MSN-aldehyde) containing lysosome activatable rhodamine-lactams were prepared for fluorescent tracking and delivery of proteins via lysosomal acidity-triggered release of proteins and "turn-on" fluorescence of doped rhodamine-lactam. The carrier-protein nanocomposites were site-specifically internalized into lysosomes of HepG2, HeLa and L929 cells where the loaded proteins, including arginase and green fluorescent protein, were released via lysosomal acidity-mediated hydrolysis of the bridging imine linkages. The released proteins efficiently escaped from lysosomes into cytosol where arginase effectively induced autophagy of the host cells. With the ease of formation of pH-labile imine linkages between MSN-aldehyde and lysine of various proteins, MSN-aldehyde would be of interest as a general vector for cytosolic delivery of proteins

A rhodamine-deoxylactam based sensor for chromo-fluorogenic detection of nerve agent simulant

N-(rhodamine B)-deoxylactam-5-amino-1-pentanol (dRB-APOH) was designed and prepared as the chromo-fluorogenic sensor for detection of a nerve agent simulant via analyte triggered tandem phosphorylation and opening of the intramolecular deoxylactam. The successful detection of diethyl chlorophosphate suggests the utility of rhodamine-deoxylactams as the chromo-fluorogenic signal reporting platform for design of sensors targeting reactive chemical species via various chemistries. (c) 2012 Elsevier Ltd. All rights reserved.NSF China [21272196, 21072161]; Natural Science Foundation of Fujian Province of China [2011J06004]; Fundamental Research Funds for the Central Universities [2011121020]; 973 National Basic Research Program of China [2012CB821600

Cytosolic delivery of proteins mediated by aldehyde-displaying silica nanoparticles with pH-responsive characteristics

Natural Science Foundation of Fujian Province [2011J06004]; Fundamental Research Funds for the Central Universities [2011121020]; NSF China [21072162, 30830092, 30921005, 91029304, 81061160512]; 973 program [2009CB522200]Synthetic carriers that enable site-specific intracellular delivery of proteins are valuable in many biomedical applications. Aldehyde-displaying silica nanoparticles (MSN-aldehyde) containing lysosome activatable rhodamine-lactams were prepared for fluorescent tracking and delivery of proteins via lysosomal acidity-triggered release of proteins and "turn-on" fluorescence of doped rhodamine-lactam. The carrier-protein nanocomposites were site-specifically internalized into lysosomes of HepG2, HeLa and L929 cells where the loaded proteins, including arginase and green fluorescent protein, were released via lysosomal acidity-mediated hydrolysis of the bridging imine linkages. The released proteins efficiently escaped from lysosomes into cytosol where arginase effectively induced autophagy of the host cells. With the ease of formation of pH-labile imine linkages between MSN-aldehyde and lysine of various proteins, MSN-aldehyde would be of interest as a general vector for cytosolic delivery of proteins

A self-referenced nanodosimeter for reaction based ratiometric imaging of hypochlorous acid in living cells

Hypochlorous acid (HOCl) is biosynthesized from hydrogen peroxide via catalysis of myeloperoxidase in lysosomes of immunological cells. Despite being harnessed by immune systems against invading pathogens, biogenic HOCl can also damage host tissues and has been associated with a number of diseases. In this edge article, Forster resonance energy transfer based ratiometric imaging of lysosomal HOCl was achieved with silica nanoparticles comprising FITC (donor dye) and a nonfluorescent chemodosimeter which turned into rhodamine (acceptor dye) upon HOCl triggered tandem oxidation and beta-elimination of the doped chemodosimeter. The nanodosimeter exhibited distinct biochemical properties relative to small molecule-based free chemodosimeters, e.g. lysosome-homing specificity and compatibility with aqueous media, enabling facile monitoring of lysosomal HOCl by conventional flow cytometry. The nanoprobe would be of broad utility for studies on in vivo generation and the impact of lysosomal HOCl in living cells or even in animals