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Background/Aims: Activated hepatic stellate cells (HSCs) are the major source of extracellular matrix (ECM). Therefore inhibiting HSC activation is considered as an effective strategy to inhibit the process of liver fibrosis. This study aimed to investigate the underlying mechanism of methyl helicterate (MH) isolated from Helicteres angustifolia on the activation of HSCs. Methods: HSC-T6 cells were treated with various concentration of MH and autophagy was inhibited by 3-Methyl adenine (3-MA) or RNA interference. Cell viability was observed by MTT assay and cell colony assay. Cell cycle and apoptosis were analyzed using flow cytometry. Autophagic vacuoles were observed by transmission electron microscopy and monodansyl cadaverine (MDC) staining. Moreover, autophagy-related genes and proteins were detected using real-time PCR and Western blot assays, respectively. Results: MH significantly inhibited HSC activation, as evidenced by the inhibition of cell viability, colony formation and the expression of α-SMA and collagen I. MH caused cell cycle arrest in G2/M phase. Moreover, MH significantly induced apoptosis through regulating the mitochondria-dependent pathway and the activity of caspases. MH treatment significantly increased lysosomes and autophagosomes, and enhanced the formation of autophagic vacuoles and autophagic flux. Interestingly, inhibiting autophagy by 3-MA or RNA interference abolished the ability of MH in inhibiting HSC activation. On the other hand, induction of autophagy promoted MH-induced HSC apoptosis. Further study showed that MH-induced HSC apoptosis and autophagy was mediated by the JNK and PI3K/Akt/mTOR pathways. Conclusion: Our results demonstrate that MH-induced HSC apoptosis and autophagy may be one of the important mechanisms for its anti-fibrosis effect. [ABSTRACT FROM AUTHOR]

The aim of this study was to probe the potential anti-H. pylori activity of the synthetic antimicrobial peptide pexiganan, which is an analog of the peptide magainin, and its nanoparticles (PNPs) that were prepared in our laboratory. To compare their antibacterial effects in vitro and in vivo, studies of H. pylori growth inhibition, kinetics and resistance assays were undertaken. The gastric mucoadhesive efficiency and H. pylori clearance efficiency of pexiganan and PNPs were evaluated in rats and mice infected with H. pylori. The eradication of H. pylori was determined using urease tests and a microbial culture method. We observed that PNPs adhered to gastric mucosa more effectively owing to a prolonged stay in the stomach, which resulted in a more effective H. pylori clearance. In addition, PNPs had greater anti-H. pylori effect than pexiganan in infected mice. The amount of pexiganan required to eradicate H. pylori was significantly less using PNPs than the corresponding pexiganan suspension. The results confirmed that PNPs improved peptide stability in the stomach and more effectively eradicated H. pylori from mice stomachs than pexiganan. [ABSTRACT FROM AUTHOR]

A series of novel 2,6-disubstituted boradiazaindacene (BODIPY) metal-free organic dyes (UY1-4) with phenothiazine (PTZ) moiety as electron donor for the dye-sensitized solar cells (DSSCs) have been designed and synthesized. Their photophysical, electrochemical and photovoltaic properties are extensively investigated. The structure-property relationship shows that the introduction of double donor-acceptor (D-A) branch and BODIPY-thiophene as the π-conjugated bridge is favorable to improve the efficiency of DSSCs. Among these dyes, UY4 comprised of double D-A branch with PTZ units as electron donor, a BODIPY-thiophene unit as bridge and 2-cyanoacrylic acid unit as electron acceptor possesses a stronger donating ability and longer absorption band. Hence, a DSSCs using UY4 showing best photovoltaic performance with a short-circuit photocurrent density (Jsc) of 12.16 mA cm-2, an open-circuit photovoltage (Voc) of 0.59 V and a fill factor (ff) of 0.68, corresponding to an overall conversion efficiency (η) of 4.89% under AM 1.5 irradiation (100 mW cm-2). This is the best reported result in the solar cell with a BODIPY dye as photosensitizer. [ABSTRACT FROM AUTHOR]

A series of novel 2,6-conjugated Bodipy metal-free organic dyes (UY5-8) with phenothiazine (PTZ) moiety as electron donor for the dye-sensitized solar cells (DSSCs) have been designed and synthesized. The optical, electrochemical properties and photovoltaic performances are extensively investigated. The structure-property relationship shows that the introduction of various auxiliary conjugated spacers and anchoring groups are favorable to changing the efficiency of DSSCs. Among these dyes, UY7 comprised of furan with lower resonance energy as linker and cyanoacetic acid unit as electron acceptor possesses a flatter structure and longer electron recombination lifetime. Hence, a DSSCs using UY7 showing best photovoltaic performance with a short-circuit photocurrent density (Jsc) of 13.64mAcm-2, an open-circuit photovoltage (Voc) of 590mV and a fill factor (ff) of 0.66, corresponding to an overall conversion efficiency (η) of 5.31% under 100mWcm-2 simulated AM 1.5 G solar irradiation. This is the best reported result in the solar cell with a Bodipy dye as photosensitizer. [ABSTRACT FROM AUTHOR]

This paper presents an innovative process scheme to fabricate convex comer in silicon for bulk micro-machined micro-mirror. This method combines deep reactive ion etching (DRIE) with anisotropy wet KOH etching process, with comer compensation structures. Using this method, proper mechanical structure, including about 650µm deep silicon recess with flat, silicon — residue free bottom, V-grooves, and U-grooves are realised simultaneously in single wafer. [ABSTRACT FROM AUTHOR]

The high pressure behaviors of Th4H15 and ThH2 are investigated by using the first-principles calculations based on the density functional theory (DFT). From the energy–volume relations, the bct phase of ThH2 is more stable than the fcc phase at ambient conditions. At high pressure, the bct ThH2 and bcc Th4H15 phases are more brittle than they are at ambient pressure from the calculated elastic constants and the Poisson ratio. The thermodynamic stability of the bct phase ThH2 is determined from the calculated phonon dispersion. In the pressure domain of interest, the phonon dispersions of bcc Th4H15 and bct ThH2 are positive, indicating the dynamical stability of these two phases, while the fcc ThH2 is unstable. The thermodynamic properties including the lattice vibration energy, entropy, and specific heat are predicted for these stable phases. The vibrational free energy decreases with the increase of the temperature, and the entropy and the heat capacity are proportional to the temperature and inversely proportional to the pressure. As the pressure increases, the resistance to the external pressure is strengthened for Th4H15 and ThH2. [ABSTRACT FROM AUTHOR]

Mol­ecules of the title compound, C11H17NO2S, are linked by paired N—H⋯O hydrogen bonds into centrosymmetric R22(8) dimers. [ABSTRACT FROM AUTHOR]

In the structure of the title complex, [CuI(C12H8N2){Ph2PCH2CH2P(O)Ph2}]·CH2Cl2, the coordination polyhedron with copper as the central atom has a distorted tetrahedral geometry formed by two N atoms from 1,10-phenanthroline, one iodide anion and one P atom from 1-(diphenylphosphino)-2-(diphenylphosphinoyl)ethane. [ABSTRACT FROM AUTHOR]

Flavobacterium columnare is an important bacterial pathogen of freshwater fish that causes high mortality of infected fish and heavy economic losses in aquaculture. The pathogenesis of this bacterium is poorly understood, in part due to the lack of efficient methods for genetic manipulation. In this study, a gene deletion strategy was developed and used to determine the relationship between the production of chondroitin lyases and virulence. The F. johnsoniae ompA promoter (PompA) was fused to sacB to construct a counterselectable marker for F. columnare. F. columnare carrying PompA-sacB failed to grow on media containing 10% sucrose. A suicide vector carrying PompA-sacB was constructed, and a gene deletion strategy was developed. Using this approach, the chondroitin lyase-encoding genes, cslA and cslB, were deleted. The ΔcslA and ΔcslB mutants were both partially deficient in digestion of chondroitin sulfate A, whereas a double mutant (ΔcslA ΔcslB) was completely deficient in chondroitin lyase activity. Cells of F. columnare wild-type strain G4 and of the chondroitin lyase-deficient ΔcslA ΔcslB mutant exhibited similar levels of virulence toward grass carp in single-strain infections. Coinfections, however, revealed a competitive advantage for the wild type over the chondroitin lyase mutant. The results indicate that chondroitin lyases are not essential virulence factors of F. columnare but may contribute to the ability of the pathogen to compete and cause disease in natural infections. The gene deletion method developed in this study may be employed to investigate the virulence factors of this bacterium and may have wide application in many other members of the phylum Bacteroidetes. [ABSTRACT FROM AUTHOR]

lavobacterium columnare is an important bacterial pathogen of freshwater fish that causes high mortality of infected fish and heavy economic losses in aquaculture. The pathogenesis of this bacterium is poorly understood, in part due to the lack of efficient methods for genetic manipulation. In this study, a gene deletion strategy was developed and used to determine the relationship between the production of chondroitin lyases and virulence. The F. johnsoniae ompApromoter (PompA) was fused to sacB to construct a counterselectable marker for F. columnare. F. columnare carrying PompA-sacB failed to grow on media containing 10% sucrose. A suicide vector carrying PompA-sacB was constructed, and a gene deletion strategy was developed. Using this approach, the chondroitin lyase-encoding genes, cslA and cslB, were deleted. The ?cslA and ?cslB mutants were both partially deficient in digestion of chondroitin sulfate A, whereas a double mutant (?cslA ?cslB) was completely deficient in chondroitin lyase activity. Cells ofF. columnare wild-type strain G4 and of the chondroitin lyase-deficient ?cslA?cslB mutant exhibited similar levels of virulence toward grass carp in single-strain infections. Coinfections, however, revealed a competitive advantage for the wild type over the chondroitin lyase mutant. The results indicate that chondroitin lyases are not essential virulence factors of F. columnare but may contribute to the ability of the pathogen to compete and cause disease in natural infections. The gene deletion method developed in this study may be employed to investigate the virulence factors of this bacterium and may have wide application in many other members of the phylum Bacteroidetes. [ABSTRACT FROM AUTHOR]

Solid state fermentation with different lignocellulolytic materials as inducers was used for lignocellulolytic enzyme production in this study. Pleurotus ostreatus strains were assessed by measuring laccase, CMCase, and xylanase activities. The secretion potential of the lignocellulolytic enzymes by wild and cultivated strains was analyzed for the first time. The wild and cultivated strain showed their unique capacities for secreting lignocellulolytic enzymes on solid-state fermentation with different lignocellulosic materials. The wild P. ostreatus strain preferred corncob for the secretion of laccase and xylanase activity, but the cultivated strain preferred poplar sawdust. The wild strain and cultivated strain showed a consistent preference for poplar sawdust for the secretion of CMCase activity. The wild strain was advantageous because it achieved the maximum hydrolytic enzyme activities within a short time period. Poplar sawdust and corncob were conducive to laccase secretion by the wild or cultivated strains and the rapid accumulation of laccase on solidstate fermentation. Additionally, continuous, stable laccase production was an extremely important advantage by solid-state fermentation of poplar sawdust, particularly in the wild strain. These findings are helpful in selecting the appropriate strain that corresponds to suitable lignocellulosic materials. The optimization of integrated industrial lignocellulolytic enzyme production can also be achieved. [ABSTRACT FROM AUTHOR]

The electronic structure and thermoelectric (TE) properties of PbSxTe1−x(x = 0.25, 0.5, and 0.75) solid solution have been studied by combining the first-principles calculations and semi-classical Boltzmann theory. The special quasirandom structure (SQS) method is used to model the solid solutions of PbSxTe1−x, which can produce reasonable electronic structures with respect to experimental results. The maximum ɀT value can reach 1.67 for p-type PbS0.75Te0.25 and 1.30 for PbS0.5Te0.5 at 800 K, respectively. The performance of p-type PbSxTe1−x is superior to the n-type ones, mainly attributed to the higher effective mass of the carriers. The ɀT values for PbSxTe1−x solid solutions are higher than that of pure PbTe and PbS, in which the combination of low thermal conductivity and high power factor play important roles. [ABSTRACT FROM AUTHOR]