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Context: Paeoniflorin (PF) and calycosin-7-glucoside (CG, Paeonia lactiflora Pall. extract) have demonstrated protective effects in ischaemic stroke. Objective: To investigate the synergistic effects of PFþCG on ischaemia/reperfusion injury in vivo and in vitro. Materials and methods: Male Sprague-Dawley rats were subjected to the middle cerebral artery occlusion/reperfusion (MCAO/R). After MCAO/R for 24 h, rats were randomly subdivided into 5 groups: sham, model (MCAO/R), study treatment (PFþCG, 40þ20 mg/kg), LY294002 (20mg/kg), and study treatmentþLY294002. Males were given via intragastric administration; the duration of the in vivo experiment was 8 days. Neurologic deficits, cerebral infarction, brain edoema, and protein levels were assessed in vivo. Hippocampal neurons (HT22) were refreshed with glucose-free DMEM and placed in an anaerobic chamber for 8 h. Subsequently, HT22 cells were reoxygenated in a 37 °C incubator with 5% CO2 for 6 h. SOD, MDA, ROS, LDH and protein levels were measured in vitro. Results: PFþCG significantly reduced neurobehavioral outcomes (21%), cerebral infarct volume (44%), brain edoema (1.6%) compared with the MCAO/R group. Moreover, PFþCG increased p-PI3K/PI3K (4.69%, 7.4%), p-AKT/AKT (6.25%, 60.6%) and Bcl-2/BAX (33%, 49%) expression in vivo and in vitro, and reduced GSK-3b (10.5%, 9.6%) expression. In vitro, PFþCG suppressed apoptosis in HT22 cells and decreased ROS and MDA levels (20%, 50%, respectively). Conclusions: PFþCG showed a synergistic protective effect against ischaemic brain injury, potentially being a future treatment for ischaemic stroke. [ABSTRACT FROM AUTHOR]

Background: Baicalin is a bioactive ingredient extracted from the root of Scutellariae radix, which is used to treat ulcerative colitis (UC). Objective: We investigated the activity of baicalin on lipopolysaccharide-stimulated RAW264.7 cells and 2,4,6-trinitrobenzene sulfonic acid-induced rats, including the attenuation of oxidant stress and apoptosis. Materials and Methods: The severity of colitis was assessed by disease activity index. The activities of catalase (CAT), glutathione peroxidase (GSH-PX), superoxide dismutase (SOD), and the content of malondialdehyde (MDA) were determined by their corresponding kits. The terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) was performed to study whether experimental colitis was associated with intestinal epithelial cell (IEC) apoptosis and the effect of baicalin on IEC apoptosis. Western blot analysis and immunocytochemistry assay were applied to determine the protein expressions. The reactive oxygen species (ROS) level in the colon of UC rats treated with baicalin was determined by ROS assay kit. Results: Baicalin remarkably upregulated the activities of CAT, GSH-PX, and SOD and decreased the content of MDA in a dose-dependent manner in vitro and in vivo. The TUNEL-positive cells in rats treated baicalin were remarkably reduced. Both Western blot analysis and immunocytochemistry assay indicated that baicalin significantly decreased the expressions of transforming growth factor beta-1, Bax protein and upregulated the expression of Bcl-2 protein. In addition, the expressions of total and cleaved caspase-3, total and cleaved caspase-9 protein, Fas, and FasL in vitro were downregulated by the treatment with baicalin. Baicalin of different doses reduced the generation of ROS in UC rats. Conclusion: Taken together, these evidences provide scientific basics for the application of baicalin in the treatment of UC and suggest that baicalin exerts its effect via suppression of oxidant stress and apoptosis. [ABSTRACT FROM AUTHOR]

Metal-dielectric core-shell nanostructures have been proposed as a light trapping scheme for enhancing the optical absorption of silicon solar cells. As a potential application of such enhanced effects, the scattering efficiencies of three core-shell structures (Ag@SiO2, Ag@TiO2, and Ag@ZrO2) are discussed using the Mie Scattering theory. For compatibility with experiment results, the core diameter and shell thickness are limited to 100 and 30 nm, respectively, and a weighted scattering efficiency is introduced to evaluate the scattering abilities of different nanoparticles under the solar spectrum AM 1.5. The simulated results indicate that the shell material and thickness are two key parameters affecting the weighted scattering efficiency. The SiO2 is found to be an unsuitable shell medium because of its low refractive index. However, using the high refractive index medium TiO2 in Ag@TiO2 nanoparticles, only the thicker shell (30 nm) is more beneficial for light scattering. The ZrO2 is an intermediate refractive index material, so Ag@ZrO2 nanoparticles are the most effective core-shell nanostructures in these silicon solar cells applications. [ABSTRACT FROM AUTHOR]

In this paper, the localized surface plasmon properties of Ag NPs and Ag/Al2O3 core-shell NPs with core radii ranging from 20–120 nm were analyzed by Mie scattering theory. Using numerical simulations, we show that an increasing shell thickness for core-shell NPs results in a red-shifted plasmon resonance peak compared to Ag core NPs. An averaged scattering efficiency under AM1.5 illumination is used to characterize the scattering abilities of different NPs. For Ag/Al2O3 core-shell structures, the averaged scattering efficiency increases and subsequently decreases with increasing shell thickness due to the competing influences of plasmon hybridization and phase delay. For larger radii NPs, such as R > 100 nm, the scattering abilities of core-shell structures are superior to those of spherical Ag NPs. [ABSTRACT FROM AUTHOR]

A GaAs metal-oxide-semiconductor (MOS) capacitor with HfO2 as gate dielectric and silicon nitride (SiNx) as the interlayer (IL) is fabricated. Experimental results show that the sample with the SiNx IL has an improved capacitance—voltage characteristic, lower leakage current density (0.785 × 10−6 A/cm2 at Vfb + 1 V) and lower interface-state density (2.9 × 1012 eV−1 cm−2) compared with other samples with N2− or NH3—plasma pretreatment. The influences of post-deposition annealing temperature on electrical properties are also investigated for the samples with SiNx IL. The sample annealed at 600°C exhibits better electrical properties than that annealed at 500°C, which is attributed to the suppression of native oxides, as confirmed by XPS analyses. [ABSTRACT FROM AUTHOR]

Densities and viscosities of methanol + dimethyl methylphosphonate and methanol + dimethyl phosphite binary mixtures were measured over a temperature range of (293.15 to 333.15) K at atmospheric pressure. The experimental data were compared with literature values. From these data, excess molar volumes ( V) were calculated. The density data were fitted to a second-order polynomial, and the viscosity data were fitted to the Andrade equation. [ABSTRACT FROM AUTHOR]

AbstractAim:To investigate the effect of HGF on proliferation, apoptosis and migratory ability of human vascular endothelial cells against gamma ray irradiation.Methods:ECV304 cells derived from adult human umbilical vein endothelial cells (HUVEC) were irradiated with a single gamma ray dose of 20 Gy. Immunocytochemistry and Western blot analysis were used to detect c-Met protein expression and HGF/c-Met signal pathway. In the HGF-treated groups, ECV304 cells were incubated with HGF (20 or 40 ng/mL) 3 h prior to irradiation. At 48 h post-irradiation, the proliferation of ECV304 cells was measured by MTT assay, the apoptosis was assessed by flow cytometry, and the migratory ability of ECV304 cells was measured by transwell chamber assay.Results:c-Met protein is expressed in ECV304 cells and can be activated by HGF. Gamma ray irradiation inhibits proliferation and migration of ECV304 cells in a dose-dependent manner. HGF significantly promoted the proliferation of ECV304 cells, and flow cytometry revealed that HGF can inhibit apoptosis of ECV304 cells. Transwell chamber assay also showed that HGF increases migration activity of endothelial cells.Conclusion:HGF may afford protection to vascular endothelial cells against gamma ray irradiation-induced damage. [ABSTRACT FROM AUTHOR]

The oxo-diperoxo molybdenum(VI) complex MoO(O2)2·2QOH (QOH = 8-quinilinol) was prepared and characterized by elemental analysis, IR and UV-Vis spectra. The ionic liquids (ILs) [bmim][BF4], [hydemim][BF4], and [bmim][PF6] were characterized by 1H-NMR and UV-Vis spectra. The epoxidation of a technical mixture of methyl oleate and methyl linoleate with H2O2, in [bmim][BF4], [hydemim][BF4] and [bmim][PF6], catalyzed by MoO(O2)2·2QOH (QOH = 8-quinilinol) and with NaHCO3 as co-catalyst has been studied for the first time. It was found that high conversions of methyl oleate and methyl linoleate to their respective oxidation products, as well as the total selectivity of their oxidation products to oxirane in [hydemim][BF4] were obtained. Also, the IL phases containing the Mo(VI) catalyst can be readily recycled by washing with diethyl ether and drying, and the Mo(VI) catalyst can be reused at least five times. [ABSTRACT FROM AUTHOR]

Abstract   Objective Therapeutic angiogenesis is a new strategy for treatment of vascular insufficiency. Hepatocyte growth factor (HGF)-induced angiogenesis has been applied to induce the neovascularization of ischemic adult tissues in preclinical studies. This report summarizes a phase I clinical trial on the safety of adenovirus-mediated human HGF (Ad-HGF) gene transfer to treat clinically significant coronary artery disease. Methods The 18 patients with severe and diffused triple vessel disease determined by coronary angiography, 1–3 of the main coronary arteries not amenable to bypassing grafting and to catheter-based revascularization were assigned to 3 study groups according to the dose of Ad-HGF (from low to high), and the total dose as follows: 5 × 109 pfu (group A, n = 6); 1 × 1010 pfu (group B, n = 6); 2 × 1010 pfu (group C, n = 6). Arterial gene transfer was performed by over-the wire balloon to the distal of the accessible artery or otherwise the ostium of the target vessels by diagnostic coronary catheter. General safety parameters and cardiac-specific parameters were measured through the preoperative period and on day 7, 21, and 35 postoperatively. The safety and tolerance of Ad-HGF for patients were evaluated according to functional and cytological assessments. Results During the acute phase up to day 35 and at 11–14 months of follow-up there were no serious adverse events. A mild fever during the first 3 days was not present at day 4, and no long term or paroxysmal fever was found. There were no acute alterations in hemodynamic parameters and the electrocardiogram remained normal. No serious pericardial effusion was reported and there were no arrhythmia on Holter registrations. Moreover, the serum levels of HGF were not changed and the serum anti-adenovirus in the patients was not detected up to day 35. Conclusions The present study demonstrates that it is feasible to safely use an adenovirus gene-transfer vector to deliver the human hepatocyte growth factor gene to individuals with clinically significant coronary artery disease by direct intracoronary injection. However, a great deal of additional work must be done before administration of Ad-HGF can be recommended for clinical practice. [ABSTRACT FROM AUTHOR]

Background: Hepatopoietin Cn (HPPCn) is a member of the leucine-rich acidic nuclear protein family (LANP), and studies of partially hepatectomized (PH) mice show that levels of HPPCn mRNA increase following liver injury. Furthermore, the recombinant human protein (rhHPPCn) was shown to stimulate hepatic DNA synthesis and activate signaling pathways involved in hepatocyte proliferation in vitro and in vivo. Aim: The aim of the study was to evaluate the protective effect of rhHPPCn on liver injury and fibrosis induced by carbon tetrachloride (CCl4) injection. Methods: Wistar rats weighing 200 g were given a single and repeated intraperitoneal injections of CCl4. Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activity in rat serum were measured using biochemical assay. Hepatic hydroxyproline (Hyp) level was determined in the hydrolysates of liver samples. Immunostaining and Masson's trichrome staining were conducted to evaluate hepatocyte proliferation and fibrosis. Results: The results showed that exogenous rhHPPCn could alleviate hepatocyte necrosis and protect the liver from the development of fibrotic lesions by proliferation stimulation. Additionally, HPPCn could reduce ALT/AST levels in rat serum following single and repeated CCl4 injection. Conclusion: It was suggested that HPPCn could protect hepatocytes from injury induced by CCl4 as a proliferation stimulator. [ABSTRACT FROM AUTHOR]

Interleukin 6 (IL-6) influences the growth and survival of multiple myeloma (MM) cells via the activation of multiple signalling cascades. Although sphingosine kinase (SPHK) signalling is known to play important roles in the regulation of cell proliferation and apoptosis, the role of SPHK activation in IL-6 signalling and in the pathology of MM remains unclear. This study found that IL-6 activated SPHK in MM cells, which mediates the suppressive effects of IL-6 on MM cell apoptosis. Both MM cell lines and primary MM cells constitutively expressed SPHK, and treatment of MM cells with IL-6 resulted in activation of SPHK in a concentration-dependent manner. Specific inhibitors of the phosphatidylinositol-3 kinase and extracellular signal-regulated kinase/mitogen-activated protein kinase pathways blocked the IL-6-induced activation of SPHK. It was further demonstrated that IL-6-induced activation of SPHK inhibited dexamethasone-induced apoptosis of MM cells. IL-6 stimulation or retroviral-mediated overexpression of SPHK1 in MM cells resulted in increased intracellular SPHK activity and upregulation of myeloid cell leukaemia-1 (Mcl-1), leading to increased cell proliferation and survival. Conversely, inhibition of SPHK1 by small interfering RNA reduced IL-6-induced upregulation of Mcl-1 and blocked the suppressive effect of IL-6 on MM cell apoptosis. Taken together, these results delineate a key role for SPHK activation in IL-6-induced proliferation and survival of MM cells, and suggest that SPHK may be a potential new therapeutic target in MM. [ABSTRACT FROM AUTHOR]

Triethylhydrogenammonium chloride-XAlCl3 Ionic Liquids (ILs) were used as a catalyst for the clean synthesis of dichlorophenylphosphine sulfide. Two synthesis routes were investigated; one of them was a reaction of sulfur and Dichlorophenylphosphine (DCPP), and another was a one-pot reaction of benzene, phosphorus, chloride, and sulfur. Effects of the ILs composition and reaction time and the quantity of the ILs on the reactions were studied. A simple product isolation procedure was achieved. The ILs showed reusable and low-consumption characters in the reaction of sulfur and DCPP. Thus the triethylhydrogenammonium chloride-XAlCl3 ILs gave this reaction a green character. [ABSTRACT FROM AUTHOR]

After exploring the structure of the dynamics derived by using the Appell equation, we propose a hierarchical tracking controller for a tri-wheeled mobile robot in this paper. With appropriately chosen privileged variables, the reduced equations are decoupled from the kinematic equations associated with the underlying nonholonomic constraints. This special character of the system makes it possible to separate the design into three levels: motion planning, kinematic, and dynamic. In the proposed scheme, a fuzzy inference engine in the kinematic level is used to update the desired trajectory computed in the motion-planning level. An adaptive sliding-mode controller is then adopted to track the new reference values of privileged variables in the dynamic level, which subsequently drives the nonprivileged variables. Simulation results show the effectiveness of such a tracking-control scheme, which concurrently takes kinematics and dynamics into consideration. All system variables can be tracked asymptotically to their desired values, which are assured by the skew-symmetric property of the Appell equation. [ABSTRACT FROM AUTHOR]

Multiple myeloma (MM) remains incurable despite the use of high-dose chemotherapy and stem cell transplantation. However, immunotherapy is expected to offer long-term disease control, or even possibly a cure. We have previously demonstrated the suppressive effect of a recombinant adenovirus carrying human wild-type p53, granulocyte–macrophage colony-stimulating factor, and B7-1 genes (Ad-p53/GM-CSF/B7-1) on the growth of laryngeal cancer cells. In the present study, we evaluated the effects of an Ad-p53/GM-CSF/B7-1-modified myeloma cell vaccine strategy aimed to induce apoptosis and to augment the immunogenicity of MM cells. Both MM cell lines and purified primary myeloma cells were infected with Ad-p53/GM-CSF/B7-1. High expression levels of these three genes were confirmed separately by Western blot, enzyme-linked immunosorbent assay (ELISA), and flow cytometry. When wild-type p53, GM-CSF and B7-1 genes were introduced, the growth of MM cells was inhibited via enhanced apoptosis and the immunogenicity of tumor cells was augmented. The combinatorial effect of these three genes on inducing cytotoxic T lymphocytes (CTLs) was more evident than that of p53 individually or any combinations of two (p53 plus GM-CSF or p53 plus B7-1). Furthermore, significant proliferation of autologous peripheral blood lymphocytes (PBLs) and specific cytotoxicity against autologous primary MM cells were induced in vitro. These results suggest that myeloma cell vaccination co-transferred with p53, GM-CSF and B7-1 genes may be a promising immunotherapeutic approach against MM. [ABSTRACT FROM AUTHOR]

The Friedel-Crafts reaction of phosphorus trichloride and benzene in [Et 4 N]Br-XAlCl 3 ([Et 4 N]Br = tetraethylammonium bromide) ionic liquids (ILs) was investigated for the clean synthesis of dichlorophenylphosphine (DCPP). A simple product isolation procedure was achieved, and the effects of IL's composition, reaction time, and quantity on this reaction were studied. The [Et 4 N]Br-XAlCl 3 ILs gave this reaction a green character. From the isolation experiments, it was found that (a) because of the formation of the complex of DCPP and AlCl 3 , the catalytic activity of the [Et 3 NH]Cl-XAlCl 3 ([Et 3 NH]Cl = triethylhydrogenamonium chloride) was reduced; (b) with the addition of quaternary ammonium to the IL's residue, additional DCPP could be recovered. [ABSTRACT FROM AUTHOR]

In our search for bioactive compounds from the whole plantof Picria felterraeLour., three new phenylethanoid glycosides, picfeosides A-C (1-3), along with five known phenylethanoid glycosides, namely wiedemannioside (4), acteoside (5), acteoside isomer (6), cis-acteoside isomer (7), and cis-acteoside (8), were isolated using several chromatographic purification steps, including semipreparation HPLC on RP-18. The structures of the new compounds were elucidated on the basis of extensive spectroscopic analysis.(Managing editor: Wei WANG) [ABSTRACT FROM AUTHOR]

Based on Jourdain's variational equation proposed in 1909, we deduce a minimal set of general equations of motion for nonholomic dynamical systems of particles and rigid bodies. This equation of motion for the system, which differs slightly from the Gibbs-Appell equation, appears to be the same as the equation derived by Kane in 1961. Since the same equation was established by Appell in 1903 on the basis of D'Alembert's principle, the newly derived equation is named Appell's equation. [ABSTRACT FROM AUTHOR]

To date, many efforts have been made to improve the performance of paintable carbon-based (PC-based) perovskite solar cells (PSCs). Though great progress has been achieved, their power conversion efficiencies are still relatively low compared with hole-transport-materials-based PSCs. General research on influencing factors of performance in PC-based PSCs is still insufficient. In this work, PC-based PSCs were fabricated in ambient air and four groups of controlled experiments were performed in which the PbI2 layers were prepared with or without antisolvent extraction treatment. These four groups of experiments were designed to find out the effect of different influencing factors on PC-based PSCs performance, for example, PbI2 residual, the surface morphology of the perovskite film, the surface roughness of the perovskite film, and the contact status of the perovskite/carbon electrode interface. With a systematic analysis, we demonstrated that the contact status of the perovskite/carbon electrode interface played a vital role in PC-based PSCs, and a flat, smooth perovskite surface could help to improve this contact status significantly. Besides, on the precondition of a poor contact interface, no PbI2 residual and a good surface morphology only brought limited benefits to the performances of PC-based PSCs. [ABSTRACT FROM AUTHOR]

A facile single-step strategy to prepare stable and water-dispersible dopamine-functionalized ultra-small mixed ferrite nanoparticles MFe2O4-DOPA (where M is a bivalent metal atom i.e. Fe, Co Cu, Mn and Ni) at room temperature is described. The nanoparticles formed have narrow size distribution as indicated by their characterization using transmission electron microscopy (TEM) and dynamic light scattering. The surface chemistry of these nanoparticles was probed by FTIR spectroscopy indicating their successful capping with dopamine ligands, which was further confirmed using zetapotential measurements and thermogravimetric analysis. The comparative horseradish peroxidase (HRP)—like activity of these cationic mixed ferrites nanoparticles was studied at pH 4.6 using a negatively-charged 2, 2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) as a chromogenic substrate in the presence of hydrogen peroxide. A time-dependent relative peroxidase-like activity follows the following order CoFe2O4-DOPA  >  MnFe2O4-DOPA  >  CuFe2O4-DOPA  >  NiFe2O4-DOPA  >  Fe3O4-DOPA. This diversity in HRP-like activity may be attributed to the different redox properties of ferrite nanoparticles when doped with M (Fe, Co Cu, Mn and Ni). [ABSTRACT FROM AUTHOR]

GaAs metal–oxide–semiconductor (MOS) capacitors with HfTiON as a gate dielectric and Ga2O3(Gd2O3) (GGO) as an interlayer annealed in NH3 or N2 are fabricated, and their electrical properties are characterized. Experimental results show that the HfTiON/GGO/GaAs MOS device annealed in NH3 exhibits a low interface-state density (1.1 × 1012 cm−2 eV−1), a small gate leakage current (1.66 × 10−4 A cm−2 at Vg = Vfb + 1 V), a large equivalent dielectric constant (25.7), and a good capacitance–voltage behavior. All these should be attributed to the fact that the GGO interlayer and postdeposition annealing in NH3 can effectively suppress the formation of interfacial Ga/As oxides and remove the excess As atoms at the GaAs surface, thus reducing the relevant defects at/near the GGO/GaAs interface. [ABSTRACT FROM AUTHOR]