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The extended Fisher–Kolmogorov (EFK) equation has been used to describe some phenomena in physical, material and biological systems. In this paper, we propose a full-rank splitting scheme and a rank-adaptive splitting approach for this equation. We first use a finite difference method to approximate the space derivatives. Then, the resulting semi-discrete system is split into two stiff linear parts and a nonstiff nonlinear part. This leads to our full-rank splitting scheme. The convergence of the proposed scheme is proved rigorously. Based on the frame of the full-rank splitting scheme, we design a rank-adaptive splitting approach for obtaining a low-rank solution of the EFK equation. Numerical examples show that our methods are robust and accurate. They can also preserve the energy dissipation. • The EFK equation is split into three subproblems, then a full-rank splitting scheme is established. The convergence of this scheme is analyzed. • A rank-adaptive low-rank approach is proposed for the EFK equation. To the best of our knowledge, this is new in the literature for the equation. • Numerical examples show that our methods are robust and accurate. They can also preserve energy dissipation. [ABSTRACT FROM AUTHOR]

In this paper, a fast linearized conservative finite element method is studied for solving the strongly coupled nonlinear fractional Schrödinger equations. We prove that the scheme preserves both the mass and energy, which are defined by virtue of some recursion relationships. Using the Sobolev inequalities and then employing the mathematical induction, the discrete scheme is proved to be unconditionally convergent in the sense of L 2 -norm and H α / 2 -norm, which means that there are no any constraints on the grid ratios. Then, the prior bound of the discrete solution in L 2 -norm and L ∞ -norm are also obtained. Moreover, we propose an iterative algorithm, by which the coefficient matrix is independent of the time level, and thus it leads to Toeplitz-like linear systems that can be efficiently solved by Krylov subspace solvers with circulant preconditioners. This method can reduce the memory requirement of the proposed linearized finite element scheme from O ( M 2 ) to O ( M ) and the computational complexity from O ( M 3 ) to O ( M log ⁡ M ) in each iterative step, where M is the number of grid nodes. Finally, numerical results are carried out to verify the correction of the theoretical analysis, simulate the collision of two solitary waves, and show the utility of the fast numerical solution techniques. [ABSTRACT FROM AUTHOR]

This paper deals with the H ∞ dynamic output feedback control problem of a seismic-excited building. The control aims to reduce the vibration of a building caused by an earthquake. Instead of system states, the system output measurements are used to design suitable H ∞ controllers. Depending on whether the system measurements are sampled or not, two kinds of dynamic output feedback control schemes are investigated. By the Lyapunov stability theory, some bounded real lemmas are formulated such that the closed-loop system is asymptotically stable and achieves a prescribed H ∞ disturbance attenuation level. The cone complementary algorithm is employed to design H ∞ controllers based on a solution to a nonlinear minimization problem subject to a set of linear matrix inequalities. Finally, a three-storey building model is given to show the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Abstract: Background: Mitogen-activated protein kinases (MAPKs) and nuclear factor-kappa B (NF-κB) signaling pathways are pleiotropic regulator of many genes involved in lipopolysaccharide (LPS)-induced acute lung injury (ALI). The present study aimed to reveal the protective effect of isotetrandrine (ITD), a small molecule inhibitor, on various aspects of LPS-induced inflammation in vitro and in vivo. Methods: In vitro, RAW 264.7 cells were pretreated with different dose of ITD 1 h before treatment with 1 mg/L of LPS. In vivo, to induce ALI, male BALB/c mice were injected intranasally with LPS and treated with ITD (20 and 40 mg/kg) 1 h before LPS. Results: In vitro, the cytokine levels of tumor necrosis factor-α, interleukin (IL)-1β, and IL-6 in supernatant were reduced by ITD. Meanwhile, in vivo, pulmonary inflammatory cell infiltration, myeloperoxidase activity, total cells, neutrophils, macrophages, along with the levels of tumor necrosis factor-α, IL-1β, and IL-6 in bronchoalveolar lavage fluid were dose-dependently attenuated by ITD. Furthermore, our data showed that ITD significantly inhibited the activation of MAPK and NF-κB, which are induced by LPS in ALI model. Conclusions: These results suggested that ITD dose-dependently suppressed the severity of LPS-induced ALI by inactivation of MAPK and NF-κB, which may involve the inhibition of tissue oxidative injury and pulmonary inflammatory process. [Copyright &y& Elsevier]

Abstract: A novel chymotrypsin-like serine protease (CLSP) was isolated from the hepatopancreas of the redclaw crayfish Cherax quadricarinatus (Cq-chy). The full-length cDNA of Cq-chy contains 951 nucleotides encodes a peptide of 270 amino acids. The mature peptide comprising 223 amino acids contains the conserved catalytic triad (H, D, and S). Similarity analysis showed that Cq-chy shares high identity with chymotrypsins from the fiddler crab; Uca pugilator. Cq-chy mRNA expression in C. quadricarinatus was shown to be: (a) tissue-related with the highest expression in the hepatotpancreas and widely distributed, (b) highly responsive in the hepatopancreas to White Spot Syndrome Virus (WSSV) challenge, and (c) differently regulated in immature and adult crayfish. In this study we successfully isolated Cq-chy. Our observations indicate that Cq-chy is differently involved in the immature and adult innate immune reactions, thus suggesting a role for CLSPs in the invertebrate innate immune system. [Copyright &y& Elsevier]

Abstract: This paper investigates the effect of a small time-delay on dynamic output feedback control of an offshore steel jacket structure subject to a nonlinear wave-induced force. First, a conventional dynamic output feedback controller is designed to reduce the internal oscillations of the offshore structure. It is found that the designed controller is of a larger gain in the sense of Euclidean norm, which demands a larger control force. Second, a small time-delay is introduced intentionally to design a new dynamic output feedback controller such that (i) the controller is of a small gain in the sense of Euclidean norm and (ii) the internal oscillations of the offshore structure can be dramatically reduced. It is shown through simulation results that purposefully introducing time-delays can be used to improve control performance. [Copyright &y& Elsevier]

Abstract: Pathogen-responsive endogenous small non-coding RNAs regulate gene expression in relation to plant immune responses by serving as RNA silencing machinery. Decay caused by the bacterium, Erwinia carotovora subsp. carotovora (Ecc), often leads to soft rot disease in the plant Brassica campestris L. ssp. pekinensis (Bcp). To discover endogenous small RNA species in Bcp in response to Ecc infection, we developed a highly efficient approach for cloning pathogen-regulated small RNAs. A group of degenerate stem–loop reverse primers was designed to synthesize first single-stranded cDNA (sscDNA) and the sscDNA was then tailed with a poly(C) at its 3′ end to create a forward priming site. A novel cDNA/RNA subtractive hybridization was performed to capture Ecc-regulated small RNAs and this subsequently allowed construction of small RNA cDNA libraries for sequencing. [Copyright &y& Elsevier]

Abstract: In this study, sub-microsized CoFe2O4 octahedra with a high yield are synthesized via a simple hydrothermal route under mild conditions. The as-prepared products are characterized by conventional techniques of XRD, SEM, TEM, ED and HR-TEM. The results show that the as-synthesized sample exhibits octahedral morphology with a narrow size distribution. The edge size of CoFe2O4 octahedra is estimated to be about 0.10–0.14μm. The growth process is also monitored by time and temperature-dependent observation. It is found that the reaction temperature has no obvious influence on the product morphology but a significant effect on the size of CoFe2O4 octahedra, while the reaction time determines the final morphology of the product. Moreover, it is displayed that the citrate ions play a key role in the formation of CoFe2O4 octahedra. Furthermore, the possible growth mechanism of the sub-microsized CoFe2O4 octahedra is discussed on the basis of a series of experiments. Magnetic measurements show that sub-micro-sized CoFe2O4 octahedra exhibit obvious ferromagnetic behaviors. The saturation magnetization (M s), remanent magnetization (M r), and coercivity (H c) are determined to be 85.8, 29.2emu/g and 892Oe, respectively. [Copyright &y& Elsevier]

Abstract: Maghemite sub-micrometer-sized spheres were successfully prepared by a simple solvothermal reduction route at relatively low temperature. The as-obtained sample was characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), electron diffraction (ED), X-ray photoelectron spectroscopy (XPS) and superconducting quantum interference device (SQUID) measurements. XRD and XPS analyses indicate the formation of γ-Fe2O3 phase. TEM results reveal that the γ-Fe2O3 particles are spherical with the diameter of 200–400nm. Magnetic measurements show that the Curie temperature of γ-Fe2O3 sub-microspheres is over 400K and the sample exhibits ferromagnetic behavior at room temperature. It is found that the sub-microspheres possess high saturation magnetization of 81emu/g at 300K. [Copyright &y& Elsevier]

Abstract: Shuttle-like α-Fe2O3 nanoparticles have been successfully synthesized via a new soft-template route using polyethylene glycol (PEG) as polymer, cetyltrimethylammonium bromide (CTAB) as surfactant and FeCl3·6H2O as iron source materials. Meanwhile, spherical α-Fe2O3 nanoparticles are also fabricated under the similar conditions without surfactant and polymer. The resultant products are characterized by means of thermalgravimetric analysis (TGA), powder X-ray diffraction (XRD), infrared (IR) spectroscopy, transmission electron micrograph (TEM), X-ray photoelectron spectra (XPS) and magnetization measurements. The homogeneous α-Fe2O3 nanoparticles with shuttle-like shape have an average length of 120nm and a mean diameter of about 50nm in the middle part (an average aspect ratio of about 2.5) whereas spherical α-Fe2O3 nanoparticles have a mean particle diameter of about 35nm. Magnetic hysteresis measurements reveal that shuttle-like α-Fe2O3 nanoparticles display normal ferromagnetic behaviors while spherical α-Fe2O3 nanoparticles exhibit weak ferromagnetic behaviors at room temperature. The two types of α-Fe2O3 exhibit hysteretic features with the remanence and coercivity of 0.156 emu/g and 664Oe, 0.048 emu/g and 110Oe, respectively. The higher remanent magnetization and coercivity of shuttle-like α-Fe2O3 nanoparticles may be associated with the aspect ratio of α-Fe2O3 since shape anisotropy would exert a tremendous influence on their magnetic properties. [Copyright &y& Elsevier]

Two two-dimensional inorganic–organic hybrid materials formulated as [{Cu(phen)}2(VVO2)2VIVO2(H2O)(PO4)2] 1 and [V4O7(2,2′-bpy)2(HPO4)2] 2 have been hydrothermally synthesized and characterized by single-crystal X-ray diffraction. Both crystallize in the triclinic space group P1¯ (no. 2), with cell parameters a=8.118(3), b=9.272(3), c=10.348(5) A˚, α=96.71(1), β=100.97(1), γ=104.66(1)°, V=728.5(5) A˚3, Z=1 for 1 and a=8.402(4), b=9.270(5), c=9.676(7) A˚, α=97.10(1), β=110.29(1), γ=98.92(1)°, V=685.4(7) A˚3, Z=1 for 2. The structure of 1 is analogous to that of [{Cu(phen)}2(VVO2)3(OH)(PO4)2] (1′) and consists of [{Cu(phen)}2VIVO6(H2O)]∞ chains that are bridged by {(VO2)(PO4)}2 4-membered rings via oxygen atoms into a two-dimensional network. Compounds 1 and 1′ are isostructural but the oxidization states of vanadium atoms in them are not fully same. Thus, 1 and 1′ are relatively rare examples of all V(V) and V(V)/V(IV) mixed valence analogues in the solid state. Compound 2 is also relatively uncommon and features 2,2′-bipy ligands directly coordinated to vanadium atoms. The structure of 2 is constructed by 4-, 6- and 8-membered rings and is topologically relevant to [V3O7(phen)]. The temperature-dependent magnetic susceptibility of 1 shows alternating ferro- and antiferromagnetic interactions. [Copyright &y& Elsevier]

• A stationary parallel-in-time iterative algorithm is proposed to solve the all-at-once discrete system of the time-fractional PDEs. • The proposed algorithm converges rapidly and robustly with respect to the discretization and problem parameters. • In each iteration, the algorithm can be implemented in a parallel-in-time manner via the diagonalization technique proposed recently. • An upper bound of the infinity norm of the iterative matrix is derived to be sharp and independent of the eigenvalues of the spatial discrete matrix. • The algorithm can be extended to handle nonlinear problems and numerical experiments show that the nonlinear version of the algorithm work well. Volterra partial integro-differential problems with weakly singular kernel attract a lot of attentions in recent years, thanks to the numerous real world applications. Solving this kind of PDEs in a parallel-in-time (PinT) pattern is difficult, because of the nonlocal property of time evolution. In this paper, we consider a class of representative problems and propose a novel iterative algorithm for PinT computation. In each iteration, we can solve the PDEs for all the discrete time points simultaneously via the diagonalization technique proposed recently. Convergence of the algorithm is analyzed by looking insight into the decreasing property of the convolution quadrature weights. We show that the convergence rate of the proposed algorithm is robust with respect to the discretization and problem parameters. Numerical results are reported to support our findings. [ABSTRACT FROM AUTHOR]

[Display omitted] • Well-tuned band structure and redox ability by adjusting electron D-A capacity of building units. • Selective thiocyanate/sulfonyl radicals generation by h+ oxidation. • Reactive oxygen species production by photogenerated e− reduction. • Tandem sulfur-based radical addition/vinyl radical coupling with ROS/enol tautomerism. • No electron sacrificial agents or extra additives as precursor of singe electron transfer reagents. Photocatalytic radical-mediated aerobic thiocyanation/sulfonylation of alkynes represents the most straightforward and atom-economic method to synthesize α-thiocyanate/sulfonyl ketones. The core issue is the generation of desired thiocyanate/sulfonyl radicals and their subsequent conversion into target products. In this work, three polyimide-based donor–acceptor COFs, named TAPB-PMDA, TTA-PMDA, and TTA-NDA, respectively, have been prepared for the photosynthesis of α-thiocyanate/sulfonyl ketones. Based on efficient adjusting electron donor-accept capacity of building units, TTA-NDA possesses broader visible absorption, richer redox properties, faster carrier separation efficiency and shows higher photocatalytic activity in thiocyanation/sulfonylation of alkynes under blue LED light illumination. Control experiments and EPR tests provide insight into the tandem radical addition/cross-coupling mechanism, in which the thiocyanate/sulfonyl radicals generation via h+ oxidation and the reactive oxygen species (ROS, e.g. •OH, H 2 O 2 , 1O 2 , O 2 •−) production by e− reduction carry out simultaneously, avoiding the employing of electron sacrificial agents or extra additives as precursors of singe electron transfer reagents. This operable strategy opens up a door for the difunctionalization of alkynes in photosynthetic manner. [ABSTRACT FROM AUTHOR]

Abstract Purpose Epilepsy is considered a disorder of neural networks. Patients diagnosed with refractory epilepsy frequently experience attention impairments. Seizure activity in epilepsy may disturb brain networks and damage the brain function of attention. The aims of this study were to assess functional and causal connectivities of the attention networks and default mode network using resting-state functional magnetic resonance imaging (fMRI). Method Resting-state fMRI data were gathered from 19 patients with refractory epilepsy (mixed localization and aetiologies) and 21 healthy people. The fMRI data were analyzed by group independent component analysis (ICA) fMRI toolbox to extract dorsal attention network (DAN), ventral attention network (VAN), and default mode network (DMN). The components of the selected networks were compared between patients and healthy controls to explore the change in functional connectivity (FC). Granger causality analysis was performed by taking the aforementioned significant brain areas as regions of interest (ROIs) to calculate autoregression coefficients of each pair of ROIs. Comparisons were done to find the significantly different causal connectivity when FC was changed between patients and healthy controls. Results In DAN, the FC values of the bilateral frontal eye field (FEF) and left intraparietal sulcus (IPS) were decreased. In VAN, the FC values of the double-side ventral prefrontal cortex (vPFC) and the temporoparietal junction (TPJ) were reduced. As for DMN, the FC values of the bilateral medial prefrontal cortices (mPFC) were decreased whereas those for the bilateral precuneus (PCUN) were increased. Granger causal connectivity values were correlated: causal influence was decreased significantly from the left IPS (in DAN) to the double side of the vPFC but remained the same for the right FEF (in DAN) to the right TPJ. The value was decreased from the left PCUN (in DMN) to the right TPJ and FEF, and the causal flow from the right PCUN to the right TPJ and bilateral vPFC was also significantly inhibited (p < 0.05). Conclusion Frequent seizures in patients with refractory epilepsy may damage the cortex and disturb DAN, VAN, and DMN, leading to functional and causal connectivity alteration. In addition, epileptic activity may disrupt network interactions and further influence information communication. Highlights • Seizures in patients with epilepsy may damage the function of attention. • The functional connectivity of the attention networks was decreased in patients with refractory epilepsy. • The causal connectivity from the default mode network to the attention networks was also inhibited. [ABSTRACT FROM AUTHOR]

This paper investigates the network-based modeling and event-triggered H ∞ reliable control for an offshore structure. First, a network-based model of the offshore structure subject to external wave force and actuator faults is presented. Second, an event-triggering mechanism is proposed such that during the control implementation, only requisite sampled-data is transmitted over networks. Third, an event-triggered H ∞ reliable control problem for the offshore structure is solved by employing the Lyapunov–Krasovskii functional approach, and the desired controller can be derived. It is shown through simulation results that for possible actuator failures, the networked controller is capable of guaranteeing the stability of the offshore structure. In addition, compared with the H ∞ control scheme without network settings, the proposed controller can suppress the vibration of the offshore structure to almost the same level as the H ∞ controller, while the former requires less control cost. Furthermore, under the network-based controller, the communication resources can be saved significantly. [ABSTRACT FROM AUTHOR]

Orai1 is one of the key components of store-operated Ca 2+ entry (SOCE) involved in diverse physiological functions. Orai1 may associate with other proteins to form a signaling complex. In the present study, we investigated the interaction between Orai1 and small conductance Ca 2+ -activated potassium channel 3 (SK3). With the use of RNA interference technique, we found that the SOCE and its associated membrane hyperpolarization were reduced while Orai1 was knocked down by a specific Orai1 siRNA in guinea pig gallbladder smooth muscle. However, with the use of isometric tension measurements, our results revealed that agonist-induced muscle contractility was significantly enhanced after Orai1 protein was knocked down or the tissue was treated by SK3 inhibitor apamin, but not affected by larger conductance Ca 2+ -activated potassium channel inhibitor iberiotoxin or intermediate conductance Ca 2+ -activated potassium channel inhibitor TRAM-34. In addition, in the presence of apamin, Orai1 siRNA had no additional effect on agonist-induced contraction. In coimmunoprecipitation experiment, SK3 and Orai1 pulled down each other. These data suggest that, Orai1 physically associated with SK3 to form a signaling complex in gallbladder smooth muscle. Ca 2+ entry via Orai1 activates SK3, resulting in membrane hyperpolarization in gallbladder smooth muscle. This hyperpolarizing effect of Orai1-SK3 coupling could serve to prevent excessive contraction of gallbladder smooth muscle in response to contractile agonists. [ABSTRACT FROM AUTHOR]

Abstract: This paper is concerned with robust integral sliding mode control for an offshore steel jacket platforms subject to nonlinear wave-induced force and parameter perturbations. A robust integral sliding mode controller is designed to stabilize the dynamic model of the offshore steel jacket platform. It is shown through simulation results that the robust integral sliding mode control scheme can reduce the internal oscillations of the offshore steel jacket platform dramatically; and the performance of the offshore steel jacket platform under the robust integral sliding mode control scheme is better than the ones under the nonlinear control scheme and the dynamic output feedback control scheme. [Copyright &y& Elsevier]

Abstract: Regulation of protein function by S-nitrosation of critical cysteines is known to be an important mechanism for nitric oxide signaling. Evidence for this comes from several different experimental approaches including the ascorbate-based biotin switch method. However technical problems with specificity and sensitivity of ascorbate reduction of S-nitrosothiols limit its usefulness and reliability. In the current study we report the use of triphenylphosphine ester derivatives to selectively reduce SNO bonds in proteins. After triphenylphosphine ester reduction, thiols were tagged with biotin or fluorescently labeled maleimide reagents. Importantly we demonstrate that these compounds are specific reductants of SNO in complex biological samples and do not reduce protein disulfides or protein thiols modified by hydrogen peroxide. Reduction proceeds efficiently in cell extracts and in whole fixed cells. Application of this approach allowed us to demonstrate S-nitrosation of specific cellular proteins, label S-nitrosoproteins in whole fixed cells (especially the nuclear compartment) and demonstrate S-nitrosoprotein formation in cells expressing inducible nitric oxide synthase. [Copyright &y& Elsevier]

Abstract: A particle-based thrust damping system is presented which considers a piston oscillating in a dry particle medium to dissipate energy through friction and inelastic collisions. An experimental setup is designed to evaluate the influence of particle properties and device parameters on damping performance. Particle properties such as size (15nm–3mm), mass and temperature (20–130°C) are evaluated in addition to device parameters such as container size and the piston''s start position. These results demonstrate the effectiveness of this new particle damping method and provide insights that may be useful in the development of future particle damping technologies. [Copyright &y& Elsevier]

Fractional Ginzburg-Landau equations as generalizations of the classical one have been used to describe various physical phenomena. In this paper, we propose a numerical integration method for space fractional Ginzburg-Landau equations based on a dynamical low-rank approximation. We first approximate the space fractional derivatives by using a fractional centered difference method. Then, the resulting matrix differential equation is split into a stiff linear part and a nonstiff (nonlinear) one. For solving these two subproblems, a dynamical low-rank approach is employed. The convergence of our method is proved rigorously. Numerical examples are reported which show that the proposed method is robust and accurate. [ABSTRACT FROM AUTHOR]

Abstract: The unfolding of proteins has been widely used for investigating the thermodynamic properties of monomeric proteins but has been used infrequently for dimeric (or oligomeric) proteins, because of the inherent cooperation of denaturation and dissociation of the dimers (oligomers). Here, we introduce a thermodynamic parameter Kobs to discriminate the diverse folding patterns of dimeric proteins. Kobs remains constant as the protein concentration increases for the true one-step curve of unfolding pattern (A), increases and reaches a plateau for one-step curves with monomeric intermediate pattern (B), and increases steadily with no plateau for one-step curves with dimeric intermediate pattern (C). [Copyright &y& Elsevier]

A facile and hard template-assisted spatial confinement strategy was presented to prepare Co SSCs@NG-800-50 catalyst with ultra-high loading of 10.26 wt%, which displays excellent transfer hydrogenation of nitrobenzene with >99% conversion and 96.3% aniline selectivity as well as other nitroaromatics in the presence of HCOOH. [Display omitted] • Co single-site catalysts are fabricated via one-step pyrolysis of DCDA and CoPc mixture. • Co SSCs content reaches 10.26 wt%, which is close to the parent CoPc molecule (10.31 wt%). • SACTEM and XAFS analysis revealed that the Co species are present as CoN 3 structure. • CoN 3 site exhibited superior performance for transfer hydrogenation of nitroaromatics. • DFT calculations disclosed the reaction mechanism of the tandem catalysis. Atomically dispersed non-noble metal single-site catalysts (SSCs) provide a promising approach to meet the catalytic requirements that traditional nanoparticles cannot accomplish. However, they often suffer from formidable challenges of cumbersome route, unmanageable loading, inevitable burial of active site and insufficient stability. Herein, we present a facile and hard template-assisted spatial confinement strategy to prepare Co SSCs embedded in N-doped graphene-like carbon (NG) with ultra-high loading of 10.26 wt%, which is close to the parent CoPc (10.31 wt%). Furthermore, the microstructure, surface area and Co loading in the titled catalysts can be easily manipulated via altering the synthesis parameters. The optimized Co SSCs@NG-800-50 catalyst shows excellent transfer hydrogenation of nitrobenzene with > 99% conversion and 96.3% aniline selectivity as well as good universality for various nitroaromatics in the presence of HCOOH. DFT calculations in combination with elaborate experiments unveil that the active H is firstly generated by the dissociation of C-H bond rather than the recognized O-H bond in HCOOH, then it is used for the hydrogenation of nitroaromatics on CoN 3 site in Co SSCs@NG-800-50 catalyst, revealing the reaction mechanism of the tandem catalysis. This report paves a novel route to design and construct efficient and high-loading non-noble metal SSCs. [ABSTRACT FROM AUTHOR]

Four cupric cluster based magnetic coordination polymers Cu 8 O(tta) 12 (ClO 4) 2 ⋅2H 2 O (1), [Cu 5 (tta) 9 ]Cl (2), Cu 3 (OH) 2 Cl (tta) 3 (3) and Cu 3 (tta) 4 Cl 2 (4) (Htta = 1- H -tetrazole) have been prepared by the same starting materials of cupric chloride and tetrazole, with the only difference of reaction temperature and pH value tuned by inorganic perchloric acid, among which complexes 2 and 3 are initially reported. Notoriously, high temperature can promote the reducing tendency of Cu(II)-to-Cu(I) in Cu/tetrazole system, whereas reducing tendency was prohibited by pH value control using perchloric acid in this work to generate cupric tetrazolate coordination polymers. Furthermore, different cupric cluster secondary building units (SBUs) such as planar Cu 4 O, trigonal prism-like Cu 8 , linear Cu 3 (OH) 2 and Cu 3 Cl 2 as well as the overall framework topologies such as bcu , asc and bct were observed. The bonding nature of chloride shows regular variation from free anion, dative Cu⋯Cl bond and normal Cu–Cl coordination bond due to Jahn-Teller effect of Cu(II) ions. The continuous regulation of reaction pH values and temperatures gave diverse 3D cupric tetrazolate coordination polymers with planar Cu 4 O(tta) 12 , trigonal prism-like Cu 8 (tta) 9 , linear Cu 3 (OH) 2 and Cu 3 Cl 2 motifs as building blocks. Image 1 [ABSTRACT FROM AUTHOR]

Creatinine is the breakdown product of creatine, a key participant in the generation of ATP and is traditionally considered to be a biologically inert waste product. Based on our earlier work, we analyzed the effects of creatinine hydrochloride on the expression of tumor necrosis factor-alpha (TNF-α), a pro-inflammatory cytokine, in a human T cell line, as well as human and mouse macrophage cell lines. Exposing cells to creatinine hydrochloride significantly reduced TNF-α mRNA and protein levels compared to control-treated cultures in all cell lines tested. Lipopolysaccharide (LPS), a potent inducer of inflammation, was employed with in mouse macrophage cell lines to induce high levels of TNF-α in order to determine whether creatinine hydrochloride could reduce preexisting inflammation. Cells treated with LPS and creatinine hydrochloride had significantly reduced TNF-α levels compared to cells treated with LPS alone. As the NF-κB signaling pathway represents a major mechanism of TNF-α generation, nuclear extracts were examined for NF-κB pathway activation. Cells exposed to CRN had significantly lower levels of NF-κB in the nucleus compared to control-treated cells. Together, these results support the hypothesis that CRN can alter anti-inflammatory responses by interfering with the activation of the NF-κB pathway. [ABSTRACT FROM AUTHOR]

Diabetic osteoporosis is a chronic complication caused by diabetes mellitus, and However, the exact mechanism of diabetes mellitus-induced osteoporosis is still unknown. In this study, we investigate the effect of miR-449 on osteogenic differentiation and its underlying mechanism in human bone marrow-derived mesenchymal stem cells (hBMSCs) with high glucose (HG) and free fatty acids (FFA) treatment. Results showed that after culturing for 14 days, high glucose (HG) and free fatty acids (FFA) treatment dramatically decreased mineralization of human bone marrow-derived mesenchymal stem cells (hBMSCs) compared with cells treated with osteogenic medium (OM) alone. We also found that miR-449 expression was up-regulated during osteogenic differentiation of hBMSCs with HG and FFA treatment. Moreover, during osteogenic differentiation of hBMSCs with HG and FFA treatment, miR-449 mimics notably decreased the alkaline phosphatase (ALP) activity and the mRNA and protein expression levels of runt-related transcription factor 2 (Runx2), ALP, collagen I, osteocalcin (OCN), and bone sialoprotein (BSP), which was remarkably increased by miR-449 inhibitors. Furthermore, miR-449 directly targets Sirt1 by binding to its 3′-UTR. Sirt1 overexpression reverses the suppressive effect of miR-449 mimics on Fra-1 mRNA and protein expression, which was also alleviated by Fra-1 overexpression. In addition, Fra-1 overexpression alleviates the inhibitory effect of miR-449 mimics on the ALP activity and the mRNA and protein of Runx2, collagen I, OCN and BSP. Taken together, our results indicated that miR-449 overexpression inhibited osteogenic differentiation of HG-FFA-treated hBMSCs through the Sirt1/Fra-1 signal pathway. It is conceivable that modulating miR-449 might provide a new therapy for intervention in diabetic osteoporosis. [ABSTRACT FROM AUTHOR]

The selective catalytic oxidation of alcohols is important both in laboratory and industrial production, and traditional oxidants cause environmentally lethal wastes. The development of dioxygen selective oxidation efficient has been pursued from atom-efficient, economic and environmental view of points. Using DFT calculation and ESI-MS experiments, we studied the activation of the Cu Cu bonded planar complex Cu 2 (ophen) 2 to dioxygen and the application of the dioxygen-copper system for the selective oxidation of alcohols. For practical application and green chemistry, this catalytic system avoided the use of a large excess of base and expensive nitroxyl derivatives. In the cycle of oxidation, two oxidative dehydrogenation processes featuring superoxide/peroxide ( I ) and hydroperoxide ( II ) occurred along with a series of conformational changes of the butterfly-like Cu-complex from stretched to folded to stretched. Additionally, we characterized the role of the water molecule as a proton mediator in the dioxygen-copper system. [ABSTRACT FROM AUTHOR]

The development of heterogeneous non-noble metal catalytic architectures that can realize the high selective and stable hydrogenation of nitroaromatics under mild conditions is a profound challenge in the catalysis community. Here we report a facile synthesis of highly nitrogen doped and uniformly embedded Co-based mesoporous carbon catalyst through a thermolysis and etching combined strategy, in which the commercial cobalt phthalocyanine and colloidal silica serve as precursor and hard template, respectively. The protocol allows for simultaneous optimization of porous features and cobalt nanoparticles of N-doped mesoporous carbon catalyst by fine-tuning thermolysis temperature. Among the as-prepared catalysts, Co@NMC-800 with lower dosage of cobalt exhibits outstanding catalytic activity and chemoselectivity for various nitroaromatics under mild condition (2.0 mol% Co, 1.0 MPa H 2 , 80 °C, <150 min), which is significantly superior to all the existing non-noble metal-based catalytic systems. Dynamic analysis further demonstrates the apparent activation energy of nitrobenzene hydrogenation is as low as 28.0 kJ/mol, accounting for the higher hydrogenation reaction rate. In addition, the synergistic effect between the CoN x and Co NPs surface wrapped thin carbon layers plays a crucial role in providing the excellent selectivity for hydrogenation of vulnerable nitroaromatics via preferential adsorption of polar nitro group. [ABSTRACT FROM AUTHOR]

Previous studies have shown that a subpopulation of granulocyte macrophage colony-stimulating factor (GM-CSF)-dependent F4/80 high CD11b high innate macrophages could be derived from bone marrow cells by continuous in vitro culturing. These cells could be induced to differentiate into M1 or M2 macrophages in vitro . In the current study, we sought to determine whether bone marrow cell-derived innate macrophages (BMIMs) could be used to fulfill an anti-inflammatory purpose by intravenous transplantation in vivo after being stimulated to differentiate into M2 macrophages. Because Th2 cytokines, such as interleukin IL-4 and IL-13, can induce macrophage polarization into M2 macrophages, we treated the BMIMs with IL-4 and IL-13 in vitro . Next, the M2 macrophages were intravenously transplanted into a typical Th2-mediated inflammatory disease model, oxazolone (OXZ)-induced colitis, to assess the anti-inflammatory activity of BMIM-derived M2 macrophages (BMIM-M2Ms) in vivo . After transplantation, the severity of intestinal inflammation was attenuated. In addition, colon lengths and mouse body weights were noticeably improved. F4/80 + CD206 + double-positive cells (displaying the markers of M2 macrophages) had accumulated in the colon tissue of BMIM-M2M-transplanted mice. This evidence demonstrated that bone marrow-derived BMIM-M2Ms could be used to alleviate OXZ-induced Th2-mediated inflammation in a mouse model in vivo . [ABSTRACT FROM AUTHOR]

We synthesized 9 kinds of FeCl 3 /[C 4 mim][Cl] (iron (III) chloride with 1-butyl-3-methylimidazolium chloride) ionic liquids from a mole composition ratio of 1/1.7 to 1.5/1. The conductivities and densities of these FeCl 3 /[C 4 mim][Cl] ionic liquids are measured in the T = (293.15 to 343.15) K range respectively. An extreme increase in the ionic conductivity of tested FeCl 3 /[C 4 mim][Cl] ionic liquid is found when the mole composition ratio of FeCl 3 to [C 4 mim][Cl] ( x ) is less than 1/1, while the conductivity smoothly decreases with the mole composition ratio of FeCl 3 to [C 4 mim][Cl] greater than 1/1. Interestingly, the viscosity of FeCl 3 /[C 4 mim][Cl] ionic liquids decreases as increasing the mole ratio of FeCl 3 in the whole mole composition range. As 1/1.7 ⩽ x ⩽ 1/1, the viscosities decrease extremely, while the trend turns smoothly as x ⩾ 1. As increasing the mole composition ratio of FeCl 3 to [C 4 mim][Cl], the thermal coefficient of expansion of FeCl 3 /[C 4 mim][Cl] ionic liquid gets larger, but the opposite trend is observed for crystal energy at T = 298.15 K according to Glasser’s theory. [ABSTRACT FROM AUTHOR]

Solvothermal reactions of metal salts, 3-amino-1,2,4-triazole-5-carboxylic acid (H 2 atzc) and ammonium oxalate in different temperature produced two metal azolate frameworks, namely, [Cu 3 (atzc) 2 (atz)(ox)]·1.5H 2 O (1) and [Co 5 (atz) 4 (ox) 3 (HCOO) 2 ]·DMF (2) (H 2 atzc=3-amino-1,2,4-triazole-5-carboxylic acid, Hatz=3-amino-1,2,4-triazole, and ox=oxalate), in which the atzc precusor was in situ decarboxylated. Structural determination reveals that 1 contains [Cu 3 (atzc) 2 (atz)] 2− layers of mixed μ 4 -atzc and μ 3 -atz ligands, which are pillared by ox 2− groups to form a 3D porous framework. Compound 2 contains 2D layers with basic spindle-shaped decanuclear units, which extended by ox 2− and formates to form 3D porous framework. Gas adsorption investigation revealed that two kinds of frameworks exhibited selective CO 2 over N 2 sorption. Moreover, activated 2 shows H 2 storage capacity. Additionally, magnetic properties of both the compounds have been investigated. [ABSTRACT FROM AUTHOR]

Highlights: [•] MiR-138 inhibits the osteogenic differentiation of MSCs. [•] MiR-138 suppresses the phosphorylation of FAK, ERK1/2, and Runx2. [•] Runx2 reduced by miR-138 is critical for the PDGF-mediated osteogenic differentiation. [ABSTRACT FROM AUTHOR]

Highlights: [•] Recent developments of direct methods for protein SNO labeling are reviewed. [•] Detailed procedures for the preparation of the biotin-phosphine substrate are reported. [•] Detailed procedures of using the phosphine substrate to label protein SNO in cells are described. [ABSTRACT FROM AUTHOR]

Abstract: One hundred and twenty-one Salmonella isolates were obtained from food, feed, and live chicken samples derived from 13 countries or regions. In this study, their subtypes were evaluated by serotyping and multilocus sequence typing (MLST), and their genetic profiles were also characterized. It was demonstrated by serotyping on these isolates that 36 various serovars were obtained in this study, of which three serotypes S. Babelsberg, S. Fresno, and S. II were first found in mainland China. Based on Simpson’s index of diversity, the serotyping method had a 0.943 discriminatory power. Meanwhile, there were a total of 42 unique sequence types (STs) characterized by MLST, and the discriminatory power of MLST (D = 0.947) was close to that of the serotyping method. In MLST, hisD revealed the highest levels of nucleotide diversity. In addition, ST-92 was the most common ST represented by 16 Salmonella isolates, followed by ST-367 which was represented by 14 isolates. Seven new alleles were identified, which were associated with other alleles and resulted in the assignment of nine new STs. It was concluded from the results that MLST was generally associated with serotype, but not associated with the epidemiological source of the samples, and antimicrobial resistance patterns. [Copyright &y& Elsevier]

Abstract: The plant-specific NAC domain proteins have been shown previously to play important roles in both abiotic and biotic stresses or in diverse developmental processes. In this research, the full-length cDNA sequence of a novel NAC (for NAM, ATAF1/2, CUC2) transcription factor gene, designated as TaNAC8, was isolated from wheat (Triticum aestivum) using in silico cloning, reverse transcription polymerase chain reaction and 3’ rapid amplification of cDNA ends PCR methods. TaNAC8 was highly homologous to the rice OsNAC8 gene and predicted to encode a protein of 481 amino acids. The encoded TaNAC8 protein contained a NAC domain in the N-terminus and a transmembrane helices motif in the C-terminus. Using the yeast one-hybrid assay, we detected that the C-terminal region of the TaNAC8 protein had transcriptional activity. TaNAC8 was expressed strongly in the developing wheat seeds, but weakly in stems and flowers. The expression of TaNAC8 in leaves was induced by the infection of the stripe rust pathogen (Puccinia striiformis f. sp. tritici) in the incompatible interaction at 24 h post inoculation, and also by treatments with methyl jasmonate and ethylene. However, salicylic acid and abscisic acid had no any significant effect on the gene expression. Several environmental stimuli, including high salinity, PEG (polyethylene glycol) treatment, and low-temperature, also enhanced the TaNAC8 expression. These results suggest that the novel TaNAC8 protein functions as a transcriptional activator involved in wheat defense responses to abiotic and biotic stresses. [Copyright &y& Elsevier]

Abstract: It is widely accepted that addictive drug use is related to abnormal functional organization in the user''s brain. The present study aimed to identify this type of abnormality within the brain networks implicated in addiction by resting-state functional connectivity measured with functional magnetic resonance imaging (fMRI). With fMRI data acquired during resting state from 14 chronic heroin users (12 of whom were being treated with methadone) and 13 non-addicted controls, we investigated the addiction related alteration in functional connectivity between the regions in the circuits implicated in addiction with seed-based correlation analysis. Compared with controls, chronic heroin users showed increased functional connectivity between nucleus accumbens and ventral/rostral anterior cingulate cortex (ACC), between nucleus accumbens and orbital frontal cortex (OFC), and between amygdala and OFC and reduced functional connectivity between prefrontal cortex and OFC and between prefrontal cortex and ACC. These observations of altered resting-state functional connectivity suggested abnormal functional organization in the addicted brain and may provide additional evidence supporting the theory of addiction that emphasizes enhanced salience value of a drug and its related cues but weakened cognitive control in the addictive state. [Copyright &y& Elsevier]

Breast cancer is the leading cause of cancer-related death in women worldwide, and despite multiple chemotherapeutic approaches, effective treatment strategies for advanced metastatic breast cancer are still lacking. Metabolic reprogramming is essential for tumor cell growth and propagation, and most cancers, including breast cancer, are accompanied by abnormalities in energy metabolism. Here, we confirmed that sodium cantharidate inhibited cell viability using the Cell Counting Kit-8, clonogenic assay, and Transwell assay. The cell cycle and apoptosis assays indicated that sodium cantharidate induced apoptosis and cell cycle arrest in breast cancer cells. Additionally, proteomic assays, western blots, and metabolic assays revealed that sodium cantharidate converted the metabolic phenotype of breast cancer cells from glycolysis to oxidative phosphorylation. Furthermore, bioinformatics analysis identified possible roles for p53 with respect to the effects of sodium cantharidate on breast cancer cells. Western blot, docking, and phosphatase assays revealed that the regulation of p53 activity by sodium cantharidate was related to its inhibition of protein phosphatase 5 activity. Moreover, sodium cantharidate significantly inhibited tumor growth in tumor-bearing nude mice. In summary, our study provides evidence for the use of sodium cantharidate as an effective and new therapeutic candidate for the treatment of human breast cancer in clinical trials. [Display omitted] • Sodium cantharidate (SCA) inhibits the viability of breast cancer cells. • SCA induces apoptosis and cell cycle arrest and inhibits tumor growth. • Regulation of energy by SCA in breast cancer cells is related to p53. • p53 regulation by SCA is dependent on inhibition of protein phosphatase 5 activity. • SCA exerts anti-breast cancer effects by inhibiting protein phosphatase 5 activity. [ABSTRACT FROM AUTHOR]

Abstract: The critical reverse micelle concentrations of C12-s-C12⋅2Br in n-heptane/n-hexanol solutions, cmcI s, have been determined by absorption spectrum method using iodine as probe. The values of cmcI s are smaller than those of the critical micelle concentrations (cmcaq s) in aqueous solution and reach a maximum at , which is similar to the variation of cmcaq with s. The variation of cmcI with s is attributed to the alteration in the spacer chain conformation, i.e. when the spacer is short enough, it may adopt stretch configuration and when the spacer is long, it tends to bend towards the continuous oil phase to achieve a more densely packing of the quaternary ammonium heads on the surface of the core. [Copyright &y& Elsevier]

Two new metal aluminium phosphate millimetre-crystals NaBa 2 Al(P 2 O 7) 2 and NaBaAl(PO 4) 2 were successfully grown by using high-temperature molten method. The crystals NaBa 2 Al(P 2 O 7) 2 and NaBaAl(PO 4) 2 are located in space groups P ¯1 and P 2 1 /c, respectively. NaBa 2 Al(P 2 O 7) 2 displays a [Al(P 2 O 7) 2 ] 1D chain structure constructed from corner-sharing linkage of novel AlP 4 O 16 9− anion groups, and the AlP 4 O 16 9− group is formed by edge-sharing connection of two P 2 O 7 dimers and one AlO 6 octahedron. However, NaBaAl(PO 4) 2 exhibits a new [Al(PO 4) 2 ] 2D layer structure composed of AlP 2 O 10 7− anion groups via corner-sharing, and the AlP 2 O 10 7− group is generated by alternate linkages of corner-sharing PO 4 and AlO 4 tetrahedra. Analysis based on Pauling's electrostatic rule and Brown's bond valence model finds that structural feature of the two anion groups is mainly responsible for their different dimension structures in addition to structure-directed role of large Ba2+. The two crystals manifest a deep-UV optical transparency below 190 ​nm and good thermal stability, making them a potential optical window material. First-principles calculations reveal that the optical bandgaps of both crystals are determined by the Ba–O groups, rather than Al–O and P–O common groups. Structural feature of anion groups is responsible for different dimension frameworks for two new deep-UV optical aluminium phosphate crystals NaBa 2 Al(P 2 O 7) 2 containing [Al(P 2 O 7) 2 ] 1D chain and NaBaAl(PO 4) 2 featuring [Al(PO 4) 2 ] 2D layer. [Display omitted] • NaBa 2 Al(P 2 O 7) 2 contains novel AlP 4 O 16 9− group. • Structure unit conformations and Ba2+ induce different frameworks. • Millimetre-crystals are grown by using high-temperature molten method. • Optical properties are determined by BaO n polyhedra. [ABSTRACT FROM AUTHOR]

• A novel dynamic event-triggered scheduling and control framework over CAN. • Two new dynamic event-triggered schedulers (DETSs). • The theoretical relationship between the DETSs and the static ETSs. • Co-design criteria on the existence of the desired event-triggered controllers and DETSs. This paper addresses the problem of event-triggered scheduling and control for active suspension of uncertain quarter vehicle suspension systems over resource-constrained controller area network (CAN). The central aim is to develop an efficient dynamic event-triggered scheduling and control co-design approach for improving suspension performance, while significantly alleviating the resource occupancy over CAN in the simultaneous presence of transmission delays and data losses. To this end, two new dynamic event-triggered schedulers (DETSs) are first developed to orchestrate the transmissions of sensor data packets at each sampling time. One salient feature of the DETSs is that the dynamic variables employed in the relevant triggering laws can unremittingly adjust their values over time, which greatly favors the dynamic scheduling of data transmissions over CAN. Then, tractable criteria for stability and suspension performance analysis as well as criteria for co-designing the desired controllers and DETSs are derived. It is shown that the co-design criteria enable comprehensive trade-off analysis between network quality of service and control quality of performance and communication efficiency. Finally, simulation results for a two-degree-of-freedom quarter vehicle model demonstrate possible improvements on ride comfort, good road holding, limited suspension stroke and actuator force, meanwhile saving a large portion of communication resource expenditure. [ABSTRACT FROM AUTHOR]

Polymorphism existing in more than one form or crystal structure exerts a profound influence on electrochemical properties. Bi-based oxides demonstrate variable coordination geometries and particularly promising candidates as electrode materials. Both designed polymorphs α - and γ - PbBiVO 5 consist of BiO 6 polyhedra, PbO 6 polyhedra and VO 4 tetrahedra. In α -PbBiVO 5 , the BiO 6 and PbO 6 polyhedra form zigzag [Bi 2 Pb 2 O 12 ] ∞ chains bridged by VO 4 tetrahedra, while in γ -PbBiVO 5 , the BiO 6 and PbO 6 polyhedra separately form [BiO 4 ] ∞ and [PbO 4 ] ∞ chains bridged by VO 4 tetrahedra. Interestingly, γ-PbBiVO 5 has a specific capacitance of 85 mAh g−1 at a current density of 0.5 ​A ​g−1, better than that of α -PbBiVO 5 by cal. 21%. Theoretical calculations reveal that γ -PbBiVO 5 at the exposed surface (011) nearly becomes conductor with bandgap as narrow as 0.02 ​eV, elucidating the enhanced electrode performance. Bader charge analysis illustrates that the [BiO 4 ] ∞ chains facilitate more charge transfer. The electrode from the optimized composite of γ -PbBiVO 5 @5 ​wt% hydrogenated graphene flakes (HG) delivers a high specific capacity of 96 ​mA ​h ​g−1 at the current density of 0.5 ​A ​g−1 and capacity retention of about 87.6% after 1000 cycles. The assembled batteries power a 3 ​V white LED. Rational structure arrangement provides a feasible strategy for advanced energy storage devices. Image 1 • A newly-synthesized Bi-based oxide demonstrates particularly promising candidates as electrode material. • Both designed polymorphs PbBiVO 5 with similar structure units displays distinctly different electrode performance. • Advantageous arrangements of Bi atoms generate advantageous electronic structures and charge transfer. • Rational structure arrangement provides a feasible strategy for advanced energy storage devices. [ABSTRACT FROM AUTHOR]

H2S is an important gaseous signalling molecule and plays a crucial role in many physiological and pathophysiological processes. In this study we report about the biological evaluation of a new class of H2S donors (benzamide and penicillame derivatives), releasing H2S upon activation by cysteine or gutathione. Anti-inflammatory effects of the “classic” H2S donor NaHS were compared with chemically synthesized compounds. U937 cells were preincubated for 1h with NaHS or with the cysteine-inducible H2S donors 5a, 5b, 8a and 8l. H2S release was induced by the addition of cysteine. The cells were then stimulated for 24h with LPS. Vice versa, U937 cells were stimulated for 6h with LPS and then posttreated for 18h with the same compounds. TNF-alpha and IL-6 levels were quantified by ELISA. Nitrite as a marker for iNOS activation was monitored by a commercially available kit. Both NaHS and the compounds 5a and 8a showed potent anti-inflammatory effects in U937 cells by downregulating TNF-alpha and IL-6 expression. In line with these results, nitrite production was also reduced. Significant anti-inflammatory effects of all compunds were observed only at concentrations above 100μM. Notably, the effect of NaHS on TNF-alpha and IL-6 expression was significantly less pronounced compared to 5a and 8a. We conclude that cysteine-inducible donors represent a new class of controllable H2S donors which could mimic the slow and continous H2S generation process in vivo. [ABSTRACT FROM AUTHOR]

Hydrogen sulfide (H2S) has been recently classified as a critical cell-signaling molecule. Literature published in the past few years increasingly suggests that H2S is a mediator of many physiological and/or pathological processes. Some of these effects are ascribed to the formation of protein persulfides, or protein S-sulfhydration (i.e. conversion of cysteine residues -SH to persulfides -S-SH). Two different approaches have been widely used to detect protein persulfides, but the selectivity of these methods have been challenged, as they do not stand on solid chemical ground. In addition, the underlying mechanisms of S-sulfhydration mediated by H2S are still unclear. In this study we report the first selective, “tag-switch” method, which can directly label protein S-sulfhydrated residues by forming stable thioether conjugates. Furthermore we demonstrate that H2S alone cannot lead to S-sulfhydration and that the two possible physiological mechanisms include reaction with protein sulfenic acids (P-SOH) or the involvement of metal centers, which would facilitate the oxidation of H2S to HS . Persulfides are predominantly located in endoplasmic reticulum and mitochondria (the organelles richest in PSOH and metal centers, respectively) and their formation appears to be highly dependant on MST enzymatic activity. While the clean Na2S solution has no effect on protein structure, polysulfides, commercially available NaHS or Na2S solutions supplemented with metal ions have dramatic effects on protein structure, leading to cleavage of disulfide bonds with concomitant persulfide formation. Physiological consequences of these reactions will be discussed. [ABSTRACT FROM AUTHOR]

Hydrogen sulfide (H2S) is a well known toxic gas that exerts damaging effects to humans at some concentrations. However at low concentrations, H2S is implicated with many cell signaling events associated with various biological functions. Currently H2S is recognized as a member of the gasotransmitter family with possible therapeutic applications as its congener-nitric oxide (NO). To understand the detailed roles of H2S in biological processes, researchers need to have tools which can allow accurately localize and measure endogenous H2S production as well as detect H2S metabolites. A major challenge towards this goal is the fact that H2S and its metabolites are part of the biological thiol pool and their reactivity does not differ significantly. The goal of our research is to develop chemical methods for the detection of H2S and its metabolites such as protein S-sulfhydration adducts. In this presentation, I will report our latest progress in this area. [ABSTRACT FROM AUTHOR]

Hydrogen sulfide (H2S) has been recognized as an important cellular signaling molecule since 2000. Literature published in past few years increasingly suggests that H2S is a mediator of many physiological and/or pathological processes. However, hydrogen sulfide’s exact mechanisms of action are still unclear. A problem in current H2S research is the lack of controllable H2S releasing agents which can selectively deliver H2S to certain locations. Research in our laboratory has been focused on the development of novel H2S donors. We have designed and synthesized several series of donors based on different structural templates. We have proved that H2S releases from these compounds are controllable. Some compounds have showed interesting activities in certain biological systems. In this presentation, our progress in this field will be reported. [ABSTRACT FROM AUTHOR]