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The lotus seedpod-based activated carbon (LSAC) is derived from pyrolysis of lotus seedpod as biomass carbon precursor, and Co3O4 is then deposited to LSAC by oxidation-precipitation and crystallization process of Co ions from Co(NO3)2 solution. The Co3O4 particles uniformly decorate on the surface and/or the inner channels of LSAC. The optimal reflection loss (RL) value of LSAC/Co3O4-paraffin wax (PW) composite reaches −39.8 dB, and the bandwidth for RL below −10 dB and −20 dB are 10.3 and 3.0 GHz, respectively, much better than that of LSAC-PW composite for the higher magnetic loss. The addition of Co3O4 particles in LSAC-PW composite significantly enhance the RL values in various thicknesses. The channels of the LSAC and decorated Co3O4 can improve the abilities of multiple scattering, dipole polarization, interface polarization and magnetic loss. This composite provides a promising method to construct high performance absorbers by using biomass carbon to tune the dielectric properties of the ferromagnetic materials.

In cellular signaling, the diverse physiological actions of biological gases, including O2, CO, NO, and H2S, have attracted much interest. Hypoxia-inducible factors (HIFs), including HIF-1 and HIF-2, are transcription factors that respond to reduced intracellular O2 availability. Polysulfides are substances containing varying numbers of sulfur atoms (H2Sn) that are generated endogenously from H2S by 3-mercaptopyruvate sulfurtransferase in the presence of O2, and regulate ion channels, specific tumor suppressors, and protein kinases. However, the effect of polysulfides on HIF activation in hypoxic mammalian cells is largely unknown. Here, we have investigated the effect of polysulfide on cells in vitro. In established cell lines, polysulfide donors reversibly reduced cellular O2 consumption and inhibited hypoxia-induced HIF-1α protein accumulation and the expression of genes downstream of HIFs; however, these effects were not observed in anoxia. In Von Hippel-Lindau tumor suppressor (VHL)- and mitochondria-deficient cells, polysulfides did not affect HIF-1α protein synthesis but destabilized it in a VHL- and mitochondria-dependent manner. For the first time, we show that polysulfides modulate intracellular O2 homeostasis and regulate HIF activation and subsequent hypoxia-induced gene expression in a VHL- and mitochondria-dependent manner.

Lead-free (1-x)Ba(Ti0.8Zr0.2)O3-x(Ba0.7Ca0.3)TiO3 (BZT-BCT) possesses comparable piezoelectric constant with lead zirconate titanate (PZT), but its poor temperature electric performances stability and low Curie temperature limit its application. Here we designed composition graded BZT-BCT films with improved temperature stability of piezoelectric, ferroelectric, and dielectric performances over a wide temperature range, and the d33 reaches 21 pm/V with hysteresis loop even at 180 °C, which is far above the Curie temperature of BZT-BCT ceramic and BZT-0.5BCT film. The excellent temperature stability is ascribed to the lattice distortion and strain gradient in the grains caused by ions diffusion, and could suppress phase transition. This work could bring forward a feasible design for dielectric/piezoelectric/ferroelectric devices operating in harsh temperature environment.

Hydrogen sulfide (H2S) is a signaling molecule used to modify neuronal transmission, regulate vascular tone, protect tissues from oxidative stress, sense oxygen, and generate ATP. Hydrogen polysulfides (H2Sn) have recently been identified as signaling molecules that mediate the activation of ion channels, regulation of tumor growth, and the transcriptional regulation of oxidative stress; some of which were previously ascribed to H2S. Cystathionine β-synthetase (CBS), cystathionine γ-lyase (CSE), and 3-mercaptopyruvate sulfurtransferase (3MST) are known as H2S-producing enzymes. 3MST also produces H2Sn and other persulfurated molecules such as cysteine persulfide, glutathione persulfide, and persulfurated proteins. The chemical interaction of H2S and nitric oxide (NO) also produces H2Sn, which may be the mechanism underlying the synergistic effect of H2S and NO that was initially reported on vascular relaxation. H2Sn and other persulfurated molecules elicit their effect via S-sulfuration (S-sulfhydration) of specific cysteine residues of the target proteins. This review article focuses on the production and roles of H2Sn as well as H2S in the central nervous system.

In this report, we systematically studied the dielectric properties of alternately doped Ba1-xSrxTiO3 films with different Ba/Sr ratios. All species are polycrystalline with an ABO3-type structure, which exhibits growth mainly along the (110) crystal face, showing intense crystallization. Regardless of the phase of the films, either ferroelectric or paraelectric, the variation in dielectric loss is insignificant, which can be attributed to the weakening of the domain wall motion. The contribution of domain wall motion to the total losses is only approximately 6.4%, as determined by hyperbolic law calculations. In addition, a model was proposed that can well explain the pinning effect of space charge on the domain wall motion. Furthermore, the FOM value and J-V characteristics indicate that the alternately doped film still possesses good dielectric performance, even in the ferroelectric phase.

In this work, Nd2(Zr1-xSnx)3(MoO4)9 (0.02 ≤ x ≤ 0.1) (NZSM) ceramics were successfully obtained through conventional solid-state route. Phase analysis, microstructure, and properties were investigated scientifically by XRD, SEM, and network analyzer, respectively. XRD results revealed that all samples with different substitution amounts of Sn4+ formed the pure phase with R-3c space group. The permittivity was related to the polarizability and the bond of Zr2-O5, the bond of Nd-O2 possessed a positive influence on Q×f. The reduced octahedral distortion and increased bond energy made the temperature coefficient more stable. Infrared reflection spectrum results showed that the permittivity was mainly caused by the absorption of phonon oscillation. The optimum properties (er = 10.34, Q×f = 74,795 GHz, τf = -13.55 ppm/°C) were obtained when x=0.02 sintered at 750 °C.

Effective adjustment of structure and morphology is considered to be an available strategy to improve the energy storage performance of supercapacitor electrode materials. Herein, a series of hierarchical NiS/carbon hexahedrons consist of self-assembling nanoplates or nanorods were synthesized via nitrilotriacetic acid (NTA)-assisted hydrothermal strategy. This study demonstrates that the micro-morphology of the unit structure constituting the hexahedrons can be controlled by adjusting the concentration of NTA. Benefiting from synergetic effect of high void space, hierarchical assembly mode and integrated composite structure, NiS/carbon hexahedrons promote adequate exposure of abundant active sites and enhance the structural stability, donating superior energy storage performance. As expected, the optimized NiS/carbon electrode (NiS/NTA-2) exhibits superb capacitive performance, including excellent specific capacitance of 1530.4 F g-1 at 1.0 A g-1 and remarkable cycle stability with 85.6% after 5000 cycles. Employing the as-prepared NiS/NTA-2 composites as positive electrode, the hybrid supercapacitor device with spectacular capacity of maximum energy density and power density up to 35.1 Wh kg-1 and 4509.3 W kg-1 and impressive long-term stability of 87.2% retention after 5000 cycles is assembled. Moreover, a light-emitting diode (LED) is successfully illuminated for up to 12 min by two devices connected in series. Based on this strategy, high-performance energy storage devices can be further developed through utilizing the modulation effect of metal complexes to design morphology controlled electrode materials.

Self-poling has been found in many two-dimensional epitaxial ferroelectric nanofilms originating from epitaxial growth clamping and has become a new research focus due to its potential applications in designing new types of ferroelectric devices. However, self-poling ferroelectrics based on internal strain gradients rather than external stimuli still do not exist. Here, we demonstrate a novel and unique design for one-dimensional structures and geometries in microscale with robust upward flexoelectric self-poling created by the application of electrospun ferroelectric fibers on a patterned substrate to introduce curving structure arises from the uneven substrate and confinement by other fibers in space. The fiber textile composed of these curving structures could resist external electric field and temperature, and can be fabricated into high performance poling-free flexible nanogenerators with outputs comparable to the poled ones. These results are conducive to providing a potential solution to the depolarization problem, to simplifying the technologies for manufacturing piezoelectric nanogenerators by avoiding the application of electric field for poling, and to providing extra freedom in controlling ferroelectric polarization and designing new types of devices.

A series of Aurivillius-phase Bi5Ti3XO15 (X = Cu, Mn, Ni, V) (BTXO: BTCuO, BTMnO, BTNiO and BTVO) were successfully prepared using a modified micro-pulling down method and their electric and magnetic properties were carefully studied. BTVO is ferroelectric at room temperature with a diamagnetic behavior due to the absence of magnetic ions in the compound. BTCuO and BTNiO show apparent ferroelectric behavior at room temperature (RT), contrarily to BTMnO which shows negligible polarization. In terms of their magnetic properties, BTMnO is a weak ferromagnetic (canted antiferromagnetic) at temperatures below 19 K, while BTCuO and BTNiO are basically paramagnetic at low temperature and possible with a short-range magnetic ordering at RT. We do not have any evidence showing the coexistence of both ferroelectric polarization and long range magnetic ordering in any of these compounds.

A newly discovered nanometer material-mediated piezoelectrochemical (PZEC) for the direct conversion of mechanical energy to chemical energy has attracted increasing attention, for its great potential to be a green dye water decomposition technique. However, it is far from being a cost-effective and practical technique because only ultrasonic can be scavenged to decomposed organic pollutant in previous studies. Here, we prepared 0.5Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Ca0.3)TiO3 (BZT-BCT) piezoelectric fibers for the degradation of dye solution via slow stirring and studied the degradation mechanism. It provides a practical, green and low-cost method for decomposing organic dye by scavenging waste mechanical energy from the surrounding environment.

Constructing functionalized carbons decorated with transition metal oxide is an efficient way to combine the cycling stability and high specific capacitance of electrodes for electric double layer capacitors and pseudocapacitors, and the morphology is undoubtedly a key factor for the electrochemical performance. Here, three activated carbons derived from biomass with different morphologies are obtained by carbonizing rosewood (R), corncob (C) and lotus seedpod (L) waste plant body, and then the bio-activated carbons decorated with Co3O4 are prepared by simple oxidation-precipitation and crystallization method. Among the R, C, L carbons, Co3O4, R-Co3O4, C-Co3O4 and L-Co3O4 composites, the L-Co3O4 composite shows best electrochemical performance. At a scan rate of 5 mV s−1, its specific capacitance reaches 1405.3 F g−1 (975 C g−1 at 1 A g−1). Furthermore, a hybrid capacitor is fabricated using L-Co3O4 as the positive electrode and activated carbon as the negative electrode, resulting in energy density of 23.1 W h kg−1, tremendous power density of 3990.6 W kg−1 and high cycling stability (80.2% retention and coulombic efficiency of 98.8% after 5000 cycles). The equipped hybrid supercapacitor device can work for more than 10 min by lighting a red bulb. Thus, this unique L-Co3O4 composite with simple fabrication method can be considered to be a promising candidate for the electrochemical energy conversion and storage.

It has been known that hydrogen sulfide and/or polysulfides are produced from a (poly)sulfurated sulfur-acceptor substrate of 3-mercaptopyruvate sulfurtransferase (MST) via thioredoxin (Trx) reduction in vitro. In this study, we used thiosulfate as the donor substrate and the catalytic reaction was terminated on the formation of a persulfide or polysulfides. We can present alternative pathway of production of hydrogen sulfide and/or polysulfides from (poly)sulfurated catalytic-site cysteine of reaction intermediates of MST via Trx reduction. Matrix-assisted laser desorption ionization tandem time-of-flight mass spectrometric analysis revealed that after prolonged incubation of MST with thiosulfate, a trisulfide adduct becomes predominant at the sulfurated catalytic-site cysteine. When these adducts were reduced by Trx with reducing system (MST:Escherichia coli Trx:E. coli Trx reductase:NADPH = 1:5:0.02:12.5 molar ratio), liquid chromatography with tandem mass spectrometric analysis for monobromobimane-derivatized H2Sn revealed that H2S2 first appeared, and then H2S and H2S3 did later. The results were confirmed by high-performance liquid chromatography-fluorescence analysis.

Previous studies indicated that bound sulfur species (BSS), including hydrogen polysulfide (H2Sn), have various physiological functions in mammalian cells. Although H2Sn molecules have been considered as secondary metabolites derived from hydrogen sulfide (H2S) based on in vitro studies or predetermined reaction formula, the physiological form of BSS and their endogenous concentration remain unclear. In the present study, we aimed to improve the usual method using monobromobimane (mBB) followed by high performance liquid chromatographic (HPLC) analysis for HS－ for simultaneous determination of H2S, H2S2, H2S3 and cysteine persulfide in biological samples. We demonstrated that mBB derivatization of H2S and H2Sn standards under alkaline conditions (pH 9.5) induced significant decreases in H2S2 and H2S3 levels and a significant increase in the H2S level in an incubation time-dependent manner. Conversely, the derivatization of mBB adducts of H2S2 and H2S3 were stable under neutral conditions (pH 7.0), which is physiologically relevant. Therefore, we re-examined the method using mBB and applied an improved method for the evaluation of H2S, H2S2, and H2S3 in mouse brain under physiological pH conditions. The concentrations of H2S and H2S2 were 0.030 ± 0.004μmol/g protein and 0.026 ± 0.002μmol/g protein, respectively. Although the level of H2S3 was below the quantification limit of this method, H2S3 was detected in mouse brain. Using the method established here, we reveal for the first time the existence of endogenous H2S2 and H2S3 in mammalian brain tissues. H2S2 and H2S3 exert anti-oxidant activity and anti-carbonyl stress effects through the regulation of redox balance in neuronal cells. Thus, our observations provide novel insights into the physiological functions of BSS in the brain and into neuronal diseases involved in redox imbalance.

The domain structures and phase evolution in mixed ferroelectric (Fe): KTa 1− x Nb x O 3 (KTN) crystals were investigated. Temperature dependent Raman spectra show that Curie temperatures of KTN and Fe: KTN are far below room temperature, but the ferroelectric domain switching was still visualized by scanning probe microscopy at room temperature. These observed domains origin from the nano-regions near the grain boundaries. In addition, the intrinsic domains (triangle for KTN and straight line/stripe for Fe: KTN) could only be observed at low temperature by transmission electron microscopy. Three phase transitions in Fe: KTN crystals were found by Raman spectroscopy and dielectric testing: 175 K for Rhombohedral-to-Orthorhombic ( R – O ), 210 K for Orthorhombic-to-Tetragonal ( O – T ) and 250 K for Tetragonal-to-Cubic ( T – C ), which is consistent with the domain behavior.

MoS 2 is a promising anode material due to its graphite-like structure and high theoretical capacity (∼670 mAh g −1 ). Fast capacity fading and severe structural deterioration as a result of repeated lithium insertion restrict its application, however. Recently, we successfully synthesized a new type of MoS 2 /C composite and found that the composite showed excellent electrochemical performance, such as by its high capacity of 982 mAhg −1 after 100 cycles. The composite was synthesized by a simplified thermal reduction method in which cetyl trimethylammonium bromide (CTAB) and silica nanospheres are used as the carbon source and template material, respectively. Such favorable capacity retention could be attributed to the large specific surface area due to the effective carbon dispersion in the composite, as well as the enlargement of the interlayer spacing in the S-Mo-S structure.

A novel electrode material of α-NiS, β-NiS and Ni3S4 particles co-decorated rGO is obtained by co-reduction of Ni2+ and GO with thiourea. The multiple nickel sulfide phases and rGO synergistically improve the electrochemical performance of the supercapacitor electrode, which shows high specific capacity of 609.4C g−1 at current density of 1 A g−1. The electrode can keep a good stability with coulombic efficiency of as high as 99.5% after 1000 cycles. The small solution and charge transfer resistances of 0.42 and 0.24 Ω indicate the positive synergistic effects of the multiple phases of NiS and graphene on the electrochemical performance.

0.5Ba(Ti0.8Zr0.2)O3-0.5(Ba0.7Ca0.3)TiO3 (0.5BZT-0.5BCT), one of the most promising lead-free piezoelectric materials invented in recent years, has not been optimized for its thin film to show best electric performance. In this work, 0.5BZT-0.5BCT thin films were fabricated via a sol-gel technique, and the effects of solvent and additive on the microstructure, morphology and dielectric, ferroelectric, and piezoelectric properties were studied. Results showed that the 2-methoxyethanol (2-MOE) solvent resulted in 0.5BZT-0.5BCT thin films with much improved microstructure and morphology in comparison with thin film from absolute ethanol solvent. Furthermore, the film becomes even denser, smoother, and more homogeneous after the monomer ethylene glycol (EG) or polyethylene glycol of 400 molecular weights (PEG400) were added into the precursor with 2-MOE as solvent. Especially, addition of PEG400 into the solvent will result in the best thin film with both less macro and micro defects and high electric performance. The 0.5BZT-0.5BCT film from 2-MOE solvent with PEG400 additive shows a high dielectric constant e up to 1756, dielectric tunability about 44%, Pr around 17.2 μC/cm2, and Ec about 39.0 kV/cm.

Aurivillius Bi6Ti3Fe2O18 thin films were deposited by pulsed laser deposition (PLD). X-ray diffraction patterns indicated that the obtained thin films were polycrystalline and belong to orthorhombic F2mm(42) space group. Ferroelectric measurements of as-obtained Bi6Ti3Fe2O18 thin films present an increasement of polarization with increasing substrate temperature which is result from a decrease of leakage current in the films. The positive-up-negative-down (PUND) measurements show switched and non-switched polarization in all of the Bi6Ti3Fe2O18 thin films, which manifest the ferroelectricity in as-deposited thin films. Fatigue-free behavior was obtained in Pt/Bi6Ti3Fe2O18/Pt capacitors. Piezoresponse force microscopy (PFM) measurements show out-of-plane piezoelectric response and demonstrate the ferroelectric polarizability.

Polysulfides are a typical type of bound sulfur, which is physiologically stable form of sulfur species, derived from the hydrogen sulfide (H2S) that is generated endogenously in cells. We previously reported that bound sulfur protects neuronal cells from oxidative injury. In the present study, we demonstrated that polysulfides inhibited cell growth and promoted neurite outgrowth in mouse neuroblastoma Neuro2A (N2A) cells. However, Na2S showed no effect on neurite outgrowth in N2A cells. Furthermore, 2-APB and SKF96365, which are typical transient receptor potential (TRP) channel inhibitors, suppressed the neurite outgrowth induced by Na2S4. These new findings suggest that bound sulfur could induce neurite outgrowth and cell differentiation of N2A cells by accelerating calcium influx.

About 20 years ago, a pungent gas was found to be the physiological mediator of cognitive function and vascular tone. Since then, studies on hydrogen sulfide (H2S) have uncovered its numerous physiological roles such as protecting various tissues/organs from ischemia and regulating inflammation, cell growth, oxygen sensing, and senescence. These effects of H2S were extensively studied, and some of the corresponding mechanisms were also studied in detail. Previous studies on the synergistic interaction between H2S and nitric oxide (NO) have led to the discovery of several potential signaling molecules. Polysulfides are considerably potent and are one of the most active forms of H2S. H2S has a significant therapeutic potential, which is evident from the large number of novel H2S-donating compounds and substances developed for manipulating endogenous levels of H2S. The Third International Conference on H2S was held in Kyoto in June 2014. One hundred and sixty participants from 21 countries convened in Kyoto to report new advances, discuss conflicting findings, and make plans for future research. This article summarizes each oral presentation presented at the conference.

Hydrogen sulfide (H2S) has been considered to be a physiological mediator since the identification of endogenous sulfides in the mammalian brain. H2S is produced from L-cysteine by enzymes such as cystathionine β-synthase (CBS), cystathionine γ-lyase (CSE), 3-mercaptopyruvate sulfurtransferase (3MST), and cysteine aminotransferase (CAT). CSE and CAT are regulated by Ca(2+). At steady-state low intracellular concentrations of Ca(2+), CSE and the 3MST/CAT pathway produce H2S. However, after intracellular concentrations of Ca(2+) increase in stimulated cells, the production of H2S by these enzymes decreases. We recently identified a fourth pathway, by which H2S is produced from D-cysteine by the enzymes D-amino acid oxidase (DAO) and 3MST. This pathway is mainly localized in the cerebellum and the kidney. The production of H2S from D-cysteine is 80 times more efficient than that from L-cysteine in the kidney, and the administration of D-cysteine to mice ameliorates renal ischemia-reperfusion injury more effectively than L-cysteine. These results suggest that D-cysteine might be used to treat renal diseases or even increase the success of kidney transplantation. We found that H2S-derived polysulfides exist in the brain and activate transient receptor potential ankyrin-1 (TRPA1) channels 300 times more potently than H2S. Although TRPA1 channels mediate sensory transduction and respond to a variety of stimuli, including cold temperature, pungent compounds and environmental irritants, their endogenous ligand(s) has not been identified. The sulfane sulfur of polysulfides is a reactive electrophile that is readily transferred to a nucleophilic protein thiolate to generate the protein persulfide or bound sulfane sulfur by sulfhydration (as referred to as sulfuration). The bound sulfane sulfur-producing activity of polysulfides is much greater than that of H2S. This review focuses on the physiological roles of H2S and H2S-derived polysulfides as signaling molecules.

In this paper, CsLiB 6 O 10 (CLBO) crystals were grown by top-seeded solution growth (TSSG) method using self-flux. The temperature and frequency dependences of the dielectric constant, dielectric loss, AC conductivity and impedance spectroscopy for different cuts CsLiB 6 O 10 crystals were investigated, also temperature characteristics of the resonance frequency and electromechanical coupling were studied. The results show that (0 0 1)-plane of CsLiB 6 O 10 crystal has the highest dielectric constant with a value of 109, highest AC conductivity and highest electromechanical coupling factor of about 17% at elevated temperature, these make CsLiB 6 O 10 crystal excellent candidate for electrical application at elevated temperature. Also the anisotropy of electric properties has strong relationship with the crystal structure.

ZnO/Co multilayers with different layers have been deposited on silicate (100) substrate by the pulsed laser deposition method. The as-deposited multilayers present the structure of amorphous phase and a narrow hysteresis loop with high saturation magnetization and low coercivity, showing the typical soft magnetic behavior. The post annealing at the elevated temperature causes the transformation from as-deposited amorphous phase to crystalline metallic cobalt and ZnO phase, as well as the interdiffusion of different layer forming CoO and ZnCo 2 O 4 phases. The presence of crystalline metallic cobalt phase with ferromagnetic (FM) and cobalt oxide (CoO) phase with antiferromagnetic (AFM) is beneficial to the FM–AFM coupling, resulting in the shift of widening of the hysteresis loop. But an excessively high annealing temperatures leads to the formation of large amount of simple or complex oxides with paramagnetic, antiferromagnetic properties, inducing the decrease of magnetic properties significantly.

In order to search candidate multiferroics, a heterostructure of Nd:BiFeO 3 /YMnO 3 (BFO/YMO) was designed. It was fabricated using a pulsed laser deposition (PLD) method on (111) Nb: SrTiO 3 substrate through layer-by-layer growth. The particularly interesting phases for Nd:BiFeO 3 ( P 4 mm ) and YMnO 3 (hexagonal and orthorhombic) were observed. This film has a high ferromagnetic Curie temperature at 420 K. The ferroelectric domain switching was observed and it exhibited large electromechanical coupling with maximum d 33 ∼73 pm/V at 10 V.

Although potassium niobate K4Nb6O17 single crystal is easy to absorb moisture due to the intercalation of water molecules in the crystal, single crystals can be grown in fiber shape using an original pulling down method. K4Nb6O17 single crystals are easy to break down in plate shape by cleavage which is in turn affected by moisture. The dielectric constant and electric polarization measurements show that K4Nb6O17 single crystal is with weak ferroelectricity.

To investigate differentiation-dependent gene expression during granulopoiesis, we established a new method to isolate six sequential differentiation stages of neutrophil progenitors from bone marrow. Neutrophil progenitors were divided into three populations by density centrifugation, followed by depletion of other lineages, and further separated by fluorescence-activated cell sorting based on the expressions of CD34, CD11b, and CD16: CD34(+) fraction from a low-density population (F1), CD11b(-)/CD16(-) (F2), CD11b(+)/CD16(-) (F3), and CD11b(+)/CD16(low) (F4) fractions with intermediate density, and CD11b(+)/CD16(int) (F5) and CD11b(+)/CD16(high) (F6) fractions from a high-density population. To examine whether this fractionation was applicable to the study of in vivo gene expression profiles during granulopoiesis, we analyzed messenger RNA levels of AML-1 and CCAAT/enhancer binding protein (EBP)-ε and two target genes of C/EBP-ε, granulocyte-macrophage colony-stimulating factor receptor common β subunit and lactoferrin, in the six fractions and peripheral blood-derived neutrophils (F7). Expression of AML-1 and C/EBP-ε peaked at F1 and F4, respectively, followed by a gradual decrease. Although granulocyte-macrophage colony-stimulating factor receptor common β subunit messenger RNA levels remained low from F1 through F6 and elevated at F7, lactoferrin messenger RNA showed a drastic increase at F3 and dropped at F5. The difference in the expression profiles of the two C/EBP-ε target genes suggests the involvement of regulators other than C/EBP-ε in the induction of the two genes. The new fractionation method is able to provide new information on maturation-dependent gene expression during granulopoiesis.

Cystathionine γ-lyase (CSE) is one of the major enzymes for the production of hydrogen sulphide (H 2 S), a multifunctional gasotransmitter in the pancreatic β-cell. We examined the mechanisms by which glucose induces CSE expression in mouse pancreatic islets and the insulin-secreting cell line MIN6. CSE expression was increased by anti-diabetic sulphonylureas, and decreased by the ATP-sensitive K + -channel opener diazoxide and the voltage-dependent Ca 2+ channel blocker nitrendipine. Application of the synthetic inhibitors of protein kinases revealed the involvement of Ca 2+ /calmodulin-dependent protein kinase (CaMK) II and extracellular signal-regulated protein kinase (ERK) in glucose- and thapsigargin-induced CSE expression. The CaMK IIδ knockdown also suppressed CSE expression. Knockdown of the transcription factors Sp1 and Elk1, both of which can be phosphorylated by ERK, blunted CSE expression. By a reporter assay, we found Sp1 may directly and Elk1 may indirectly regulate CSE expression. These findings suggest Ca 2+ -dependent CSE expression may be mediated via protein phosphorylation of Sp1 and Elk1 in pancreatic β-cells.