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Changsha, China

Yuan L.,Hunan University | Zuo Q.-P.,First Hospital of Changsha
Sensors and Actuators, B: Chemical

Hydrogen sulfide (H2S) is now recognized as an important biological regulator and plays an important role in a vast number of physiological and pathological processes. However, understanding the important functions of H2S has remained challenging, in part due to the lack of tools for detecting endogenous H2S. Here, compound 2 was synthesized with one step reaction as a novel fluorescent turn-on probe for H2S on the basis of H2S-promoted thiolysis of dinitrophenyl ether. This free probe displayed almost no background signals due to both PET and ICT double signaling quenching mechanism. Thus, this probe shows large fluorescent turn-on and selectivity response to H2S and can be used for the fluorescence detection of both exogenous and endogenous H2S in cells with satisfactory sensitivity. Moreover, it was also applied for direct visualization of H2S in living tissues with two-photon microscopy. In addition to providing a highly sensitive and selective reaction-based fluorescent probe for H2S, the insights into the double signaling quenching mechanism controlling the signal-to-noise ratio of fluorescent turn-on probe may guide the design of fluorescent turn-on probes with better signal-to-noise ratio. © 2014 Elsevier B.V. Source

Qin F.,University of South China | Zhang Z.,First Hospital of Changsha
Journal of Central South University (Medical Sciences)

JNK signaling pathway plays an important role in regulation of cell growth, proliferation, differentiation, migration and apoptosis. Studies have shown that JNK signaling pathway is closely related to autophagy, but the underlying mechanisms are not clear. Clarification of the correlation between the JNK signaling pathway and autophagy may provide opportunities for identifying potential molecular targets for the treatment of diseases associated with autophagy. Source

Li H.,Central South University | Yuan X.,First Hospital of Changsha | Qiu L.,Central South University | Zhou Q.,Central South University | Xiao P.,Central South University
Renal Failure

Results: The efficacy analysis showed that 11 patients achieved complete remission and 17 patients achieved partial remission, and the effective remission rate was 73.7%. In addition, 10 patients achieved no remission.Conclusions: Adefovir dipivoxil combined with corticosteroids has a certain efficacy on the HBV-GN and displays few adverse reactions. A large sample, randomized double-blind controlled study and long-term follow-up are needed to verify the efficacy of adefovir dipivoxil combined with corticosteroids.Objective: To investigate the treatment efficacy of adefovir dipivoxil combined with a corticosteroid on hepatitis B virus-associated glomerulonephritis (HBV-GN).Methods: A total of 38 patients with nephrotic syndrome induced by HBV-GN were treated for 36 weeks between 2010 and 2012. © 2014 Informa Healthcare USA, Inc. All rights reserved. Source

Liu F.,Central South University | Liao F.,Central South University | Li W.,First Hospital of Changsha | Han Y.,First Hospital of Shijiazhuang City | Liao D.,Central South University
Molecular Medicine Reports

Previous studies have demonstrated that progesterone has neuroprotective effects in the central nervous system (CNS) following traumatic brain injury (TBI). Numerous cellular mechanisms have been reported to be important in the neuroprotective effects of progesterone, including the reduction of edema, inflammation and apoptosis, and the inhibition of oxidative stress. However, the effect of progesterone on neuronal protection following TBI remains unclear. The present study aimed to investigate the effects of progesterone on the expression of Nogo-A, an inhibitor of axonal growth, glial fibrillary acidic protein (GFAP), a main component of the glial scar and growth-associated protein-43 (GAP-43), a signaling molecule in neuronal growth in TBI rats. The TBI model was produced by the weight drop method. In total, 75 rats were assigned to three groups: the sham group, TBI group with vehicle treatment and TBI group with progesterone treatment. The protein expression of Nogo-A, GFAP and GAP-43 in the cortex and the hippocampus was examined by immuno-cytochemistry. TBI rats significantly increased the expression of Nogo-A, GFAP, and GAP-43 at 1, 3, 7 and 14 days post-injury. Progesterone significantly decreased the expression of Nogo-A and GFAP, and upregulated the GAP-43 protein. Our findings suggested that progesterone promotes neuroprotection following TBI by inhibiting the expression of Nogo-A and GFAP, and increasing GAP-43 expression. Source

Yuan L.,Hunan University | Zuo Q.-P.,First Hospital of Changsha
Chemistry - An Asian Journal

Hydrogen sulfide (H2S) is connected with various physiological and pathological functions. However, understanding the important functions of H2S remains challenging, in part because of the lack of tools for detecting endogenous H2S. Herein, compounds Ratio-H2S 1/2 are the first FRET-based mitochondrial-targetable dual-excitation ratiometric fluorescent probes for H2S on the basis of H2S-promoted thiolysis of dinitrophenyl ether. With the enhancement of H2S concentration, the excitation peak at λ≈402 nm of the phenolate form of the hydroxycoumarin unit drastically increases, whereas the excitation band centered at λ≈570 nm from rhodamine stays constant and can serve as a reference signal. Thus, the ratios of fluorescence intensities at λ=402 and 570 nm (I402/I570) exhibit a drastic change from 0.048 in the absence of H2S to 0.36 in the presence of 180 μM H 2S; this is a 7.5-fold variation in the excitation ratios. The favorable properties of the probe include the donor and acceptor excitation bands, which exhibit large excitation separations (up to 168 nm separation) and comparable excitation intensities, high sensitivity and selectivity, and function well at physiological pH. In addition, it is demonstrated that the probe can localize in the mitochondria and determine H2S in living cells. It is expected that this strategy will lead to the development of a wide range of mitochondria-targetable dual-excitation ratiometric probes for other analytes with outstanding spectral features, including large separations between the excitation wavelengths and comparable excitation intensities. Don't panic - FRET! The first Förster resonance energy transfer (FRET)-based dual-excitation ratiometric fluorescent probe for monitoring H2S in mitochondrial of living cells is described (see picture). Favorable properties of the probe include large separations of the donor and acceptor excitation bands, comparable excitation intensities, high sensitivity and selectivity, and good function at physiological pH. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

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