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Development of high-efficiency anode electrocatalysts remains a challenge for direct methanol fuel cells (DMFCs). Herein, carbon dots (CDs) and Co-substituted sandwich polyoxometalate K10[Co4(H2O)2...

Development of semiconductor catalysts is an attractive way to solve energy shortage and pollution problems. In this work, a kind of ternary heterojunction nanocomposite g-C3N4/Co3O4/Ag2O was successfully prepared, whose morphology, structure and composition were characterized by TEM, EDS, XRD and XPS analysis. Photocatalytic experiments prove that g-C3N4/Co3O4/Ag2O shows good photodegradation efficiency (98.09%) for RhB under visible light. The free radical capture experiment indicates that the hole, superoxide radical and hydroxyl radical all contribute to the photocatalytic process. In addition, it is found that introducing Ag2O into the composite can efficiently promote the formation of H2O2via the reduction of O2. An electrochemical oxygen reduction reaction (ORR) study further confirms that the value of electron transfer during the ORR is 2.07 for g-C3N4/Co3O4/Ag2O, indicating the promoted two-electron O2 reduction reaction to H2O2. Based on the above results and energy band structures of semiconductors, a possible photocatalysis mechanism is proposed.

Two new tungstosilicates (C(NH2)3)5KNa2H3[Sn(CH2CH2COOCH3)Co(H2O)2Si2W19O69]·10H2O (Si2W19-Co-SnRCOOCH3) and (C(NH2)3)5KNa2H3[Sn(CH2CH2COOCH3)Mn(H2O)2Si2W19O69]·13H2O (Si2W19-Mn-SnRCOOCH3) modified by organometal (OM) and transition metal (TM) ions were obtained, and they were self-assembled from mono-TM-containing (TM = Co, Mn) γ-[SiW10O35]6- (γ-SiW10)-based dimeric tungstosilicate and estertin Cl3SnCH2CH2COOCH3 in an acetate buffer solution, respectively. Their structures were determined with a series of physico-chemical and spectroscopic methods including X-ray crystallography, XRPD, etc. The estertin functional position in the tungstosilicate skeleton was analyzed by theoretical calculations using density functional theory (DFT). These two compounds have good catalytic activity for the oxidation of cyclohexanol to cyclohexanone. Meanwhile, they were composited with TiO2 using a facial layer-by-layer (LBL) method. The assembled composite films {Si2W19-TM-SnRCOOCH3/TiO2}n (TM = Co, Mn; n is the bilayer number, n = 1-6) exhibit efficient photoelectrocatalytic activity for the oxidation of methanol under irradiation of 100 mW cm-2 using a Xe lamp as a light source. And the {Si2W19-Co-SnRCOOCH3/TiO2}4 film produces the highest photocurrent among the composite films studied in this work. Combining the dark current measurement, surface photovoltage spectroscopy (SPV) and electrochemical impedance spectroscopy (EIS), the enhanced photoelectrocatalytic activity of {Si2W19-Co-SnRCOOCH3/TiO2}4 composite film for the oxidation of methanol is attributed to the suppressed electron-hole recombination, increased carrier separation efficiency and interfacial charge transfer.

Cysteine, as an important amino acid in the human body, plays a vital role in people's normal life activities. In this paper, a ratiometric fluorescent probe for detecting cysteine was designed and synthesized based on the fluorescence resonance energy transfer (FRET) process. In this FRET system, a coumarin derivative was used as the energy donor, a rhodol fluorophore was chosen as the energy receptor, and an acrylate group was utilized as a cysteine recognition unit. In the absence of cysteine, the rhodol receptor was in the non-fluorescent lactone state and the FRET process was inhibited. Upon addition of cysteine, the closed spirolactone form was converted to a conjugated fluorescent xanthene form to induce the occurrence of FRET which resulted in a fluorescent signal decrease at 470 nm and enhancement at 543 nm. The ratiometric fluorescent probe exhibited excellent selectivity to Cys over Hcy and GSH. In addition, I543nm/I470nm of the probe for cysteine displayed a good linear relationship in the range of 5.0 × 10−7–1.0 × 10−4 mol L−1, and the detection limit was 2.0 × 10−7 mol L−1. Furthermore, the probe showed low cell toxicity and was successfully applied to the confocal imaging of cysteine in HepG2 cells using dual emission channels.

A novel complex based on the Dawson-like [H3BiW18O60]6−, i.e. (C2H9N2)2[{Cu(C10H8N2)(C2H8N2)}2(H3BiW18O60)]·5.5H2O or (enH)2[{Cu(2,2′-bipy)(en)}2(μ4-H3BiW18O60)]·5.5H2O, (1), where enH is protonated ethane-1,2-diamine, 2,2′-bipy is 2,2′-bipyridine and en is ethane-1,2-diamine, has been synthesized hydrothermally and characterized by elemental analysis, single-crystal X-ray diffraction analysis, IR spectroscopy, powder XRD, and thermogravimetry and differential thermal analysis (TG–DTA). For (1), each [H3BiW18O60]6− anion acts as a tetradentate ligand connecting [Cu(2,2′-bipy)(en)]2+ fragments via two terminal and two bridging O atoms, forming a two-dimensional network structure. Along the a and c axes, polyoxometalate units are arranged in an AB…AB manner. The electrochemical behaviour of (1)–CPE (CPE is a carbon paste electrode) was investigated in 2 M H2SO4 solution by cyclic voltammetry (CV). The redox process of WVI/V takes place at E 1/2 = −0.58 (I–I′) and −0.37 V (II–II′), and at −0.04 V (III–III′) for CuII/0. The magnetic properties of (1) were investigated in the range 2–300 K and indicated the existence of strong antiferromagnetic exchange interactions between the Cu2+ centres.

Current therapeutic strategies cannot eradicate hepatitis B virus covalently closed circular DNA (HBV cccDNA), which accounts for the persistence of HBV infection. Very recently, the clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein 9 (Cas9) system has been used as an efficient and powerful tool for viral genome editing. Given that the primary duck hepatocyte (PDH) infected with duck hepatitis B virus (DHBV) has been widely used to study human HBV infection in vitro, the present study aimed to demonstrate the targeted inhibition of DHBV DNA, especially cccDNA, by the CRISPR/Cas9 system using this model. We designed six single-guide RNAs (sgRNA1-6) targeting the DHBV genome. The sgRNA/Cas9 plasmid was transfected into DHBV-infected PDHs, and then DHBV total DNA (in culture medium and PDHs) and cccDNA were quantified by reverse transcription-quantitative polymerase chain reaction. The combined inhibition of CRISPR/Cas9 system and entecavir (ETV) was also assessed. Two sgRNAs, sgRNA4 and sgRNA6, exhibited efficient inhibition on DHBV total DNA (77.23 and 86.51%, respectively), cccDNA (75.67 and 85.34%, respectively) in PDHs, as well as DHBV total DNA in the culture medium (62.17 and 59.52%, respectively). The inhibition remained or enhanced from day 5 to day 9 following transfection. The combination of the CRISPR/Cas9 system and ETV further increased the inhibitory effect on DHBV total DNA in PDHs and culture medium, but not cccDNA. The CRISPR/Cas9 system has the potential to be a useful tool for the suppression of DHBV DNA.

The anion form of a cobalt substituted mono-lacunary Keggin type polyoxometalate (POM) complex in aqueous solution was identified as [Co(H2O)(H3PW11O39)]2− and its stability constant was determined to be 5.19 × 104 by spectrophotometry. Additionally, the electrocatalytic performances towards water oxidation of different concentrations of [Co(H2O)(H3PW11O39)]2− were investigated in the neutral phosphate buffer solution, and it was found that [Co(H2O)(H3PW11O39)]2− anion itself has little activity; the activity of [Co(H2O)(H3PW11O39)]2− solution actually results from dissociated [Co(H2O)6]2+. This work provides a simple way to understand the origin of catalytic water oxidation activity of a POM-based complex.

To achieve scalable applications in solar hydrogen production, it is necessary to develop visible-light-responsive photocatalysts that are highly efficient, cost-effective, stable and environmentally-benign. Here narrow bandgap Zn–Cd–S solid solution photocatalysts (Eg = 2.11–2.53 eV) were prepared via a facile and green hydrothermal strategy under mild conditions. Amazingly, over the naked Zn0.5Cd0.5S photocatalyst, an extraordinarily high H2 production activity in Na2S–Na2SO3 aqueous solution is achieved up to 18.3 mmol h−1 g−1 with an apparent quantum efficiency of 73.8% per 50 mg under 420 nm light irradiation, which, to our knowledge, outperforms cocatalyst-free metal sulfide photocatalysts previously reported to date. Such super high performance arises from the enhanced visible-light-absorption capacity, suitable conduction and valence band potential together with the facilitated charge transport in Zn–Cd–S solid solutions. This work may open an avenue for the green preparation of inexpensive photocatalysts for solar H2 production.

Aim To investigate the mechanism of hepatoprotection conferred by liver fibrosis through evaluating the activation phenotype of kupffer cells. Methods Control and fibrotic mice were challenged with a lethal dose of D-GalN/lipopolysaccharide (LPS), and hepatic damage was assessed by histology, serum alanine transferase (ALT) levels, and hepatic expression of HMGB1, a potent pro-inflammatory mediator. The localization of F4/80 (a surrogate marker of KCs), HMGB1, and type I collagen (Col-1) was determined by immunofluorescence staining. The phenotype of KCs was characterized by real-time PCR. KCs isolated from control or fibrotic mice were challenged with LPS or HMGB1 peptide, and HMGB1 translocation was analyzed. Results Liver fibrosis protected mice against D-GalN/LPS challenge, as shown by improved hepatic histology and reduced elevation of ALT compared with the normal mice treated in the same way. This hepatoprotection was also accompanied by inhibition of HMGB1 expression in the liver. Co-localization of F4/80, HMGB1, and Col-1 was found in fibrotic livers, indicating the close relationship between KCs, HMGB1 and liver fibrosis. KCs isolated from fibrotic mice predominantly exhibited an M2-like phenotype. In vitro experiments showed that HMGB1 was localized in the nucleus of the majority of M2-like KCs and that the translocation of HMGB1 was inhibited following stimulation with LPS or HMGB1 peptide, while both LPS and HMGB1 peptide elicited translocation of intranuclear HMGB1 in KCs isolated from the control mice. Conclusion M2-like Kupffer cells in fibrotic liver may exert a protective effect against acute insult by inhibiting the translocation of HMGB1.

Hesperidin, a natural compound, suppresses the epithelial-to-mesenchymal transition through the TGF-β1/ Smad signaling pathway. However, studies on the detailed effects and mechanisms of hesperidin are rare. The present study showed that, for A549 alveolar epithelial cells, the anti-proliferative effects of hesperidin occurred in a dose-dependent manner, with an IC50= 216.8 μM at 48 h. TGF-β1 was used to activate the Smad signaling pathway and induce the epithelial to mesenchymal transition in cells. Treatment with hesperidin or SB431542 was used for antagonism of Smad pathway activation. Hesperidin inhibited the increase in ɑ-SMA and Col1ɑ-1 and the decrease in E-cadherin in a dose-dependent manner from concentration of 20 μM to 60 μM, as assessed by both ELISA and Western blotting assays; however, there was no significant effect on cellular morphological alterations. Moreover, the Western blotting assay showed that, in the cytoplasm, hesperidin and SB431542 had no significant effect on the protein expression of Smad 2, 3, 4, or 7 as well as 2/3. However, 60 μM hesperidin and SB431542 significantly decreased p-Smad2/3 protein expression. From the above results, it is concluded that hesperidin can partly inhibit the epithelial to mesenchymal transition in human alveolar epithelial cells; the effect accounts for the blockage of the phosphorylation of Smad2/3 in the cytoplasm rather than a change in Smad protein production in the cytoplasm.

Carboxyethyltin and first-row transition metals (TMs) were firstly introduced into trivacant Keggin-type tungstoantimonate in an aqueous solution, leading to the formation of four crystalline organic–inorganic hybrid sandwich-type polyoxometalates (POMs), formulated as Na10−x−yKyHx[((TM)(H2O)3)2(Sn(CH2)2COO)2(SbW9O33)2]·nH2O (SbW9-TM-SnR, TM = Mn, Co, Ni, Zn; x = 1, 1, 0, 0; y = 0, 5, 5, 2; n = 18, 24, 24, 22, respectively). SbW9-TM-SnR exhibit high catalytic ability for the oxidation of cyclohexanol. Meanwhile, SbW9-TM-SnR were composited with polypyrrole (PPy) through an electropolymerization process, forming PPy-SbW9-TM-SnR, on which platinum (Pt) was further electro-deposited to prepare PPy-SbW9-TM-SnR/Pt for electrocatalytic methanol (CH3OH) oxidation in acid solution. The composition and morphology of PPy-SbW9-TM-SnR/Pt were determined by IR, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS). The electrochemical experimental results show that SbW9-TM-SnR and PPy obviously enhance the electrocatalytic and anti-intoxication abilities of Pt, and the highest peak current density of 0.87 mA cm−2, corresponding to 1.85 and 1.43 times higher than those of pure Pt and PPy/Pt electrodes respectively, is acquired for the PPy-SbW9-Ni-SnR/Pt composite electrode. These findings may enlarge the application of PPy and POMs in the electrocatalytic field.

A kind of broad spectral responsive photoelectrode has been assembled from open-chain carboxyethyltin functionalized Dawson sandwich-type polyoxometalates (POMs) [{Sn(CH2)2COO}2M2(P2W15O56)2]16− (SnR-M-P2W15, M = Mn, Co, Cu and Zn) and organic dyes such as rhodamine B (RhB) and methylene blue (MB) through the layer-by-layer (LBL) self-assembly method. SnR-M-P2W15 shows strong adsorption towards RhB and MB. The adsorption capacity of SnR-Co-P2W15 towards RhB and MB reached 217.36 and 288.76 mg g−1 in 10 min, respectively. Compared to Keggin sandwich-type open-chain carboxyethyltin–POM and closed-ring carboxyethyltin–POM derivatives such as [Zn2{Sn(CH2)2COO}2[(PW9O34)2]10− (SnR-Zn-PW9) and [K3{Sn(CH2)2COO}2(PW9O34)2]11− (SnR-PW9), and the parent POMs [M4(H2O)2(P2W15O56)2]16− (M-P2W15, M = Mn, Co, Cu and Zn), SnR-M-P2W15-based photoelectrodes showed significantly enhanced photocurrent owing to their greater visible light harvesting. Also, the photoelectric performances of LBL multilayer films can be adjusted by controlling the number of deposited layers, adsorbed dye types and incorporated transition metal ions in the POMs.

A new polyoxometalate (POM) estertin derivative, {C(NH2)3}Na10K7[(W4O16){Sn(CH2)2COO}4(B-α-AsW9O33)2]·25H2O (1), has been synthesized from K14[As2W19O67(H2O)]·nH2O ({As2W19}) and Cl3SnCH2CH2COOCH3, which exhibits an unusual boat-like structural feature: four [Sn(CH2)2COO]2+ groups surround a center W4O16 cluster and link two [AsW9O33]9− subunits. 1 shows efficient oxidation catalytic activity and can be applied for mimicking enzyme catalysis.

Time-correlation coincidence counts of neutrons are an important means to measure attributes of nuclear material. The main deficiency in the analysis is that an attribute of an unknown component can only be assessed by comparing it with similar known components. There is a lack of a universal method of measurement suitable for the different attributes of the components. This paper presents a new method that uses universal relations to estimate the mass and neutron multiplication factor of any uranium component with known enrichment. Based on numerical simulations and analyses of 64 highly enriched uranium components with different thicknesses and average radii, the relations between mass, multiplication and coincidence spectral features have been obtained by linear regression analysis. To examine the validity of the method in estimating the mass of uranium components with different sizes, shapes, enrichment, and shielding, the features of time-correlation coincidence-count spectra for other objects with similar attributes are simulated. Most of the masses and multiplications for these objects could also be derived by the formulation. Experimental measurements of highly enriched uranium castings have also been used to verify the formulation. The results show that for a well-designed time-dependent coincidence-count measuring system of a uranium attribute, there are a set of relations dependent on the uranium enrichment by which the mass and multiplication of the measured uranium components of any shape and size can be estimated from the features of the source-detector coincidence-count spectrum.

In the field of material chemistry, it is of great significance to develop abundant and sustainable materials for solar energy harvesting and management. Herein, after evaluating the energy band characteristics of 13 kinds of polyoxometalates (POMs), the trisubstituted POM compound K6H4[α-SiW9O37Co3(H2O)3]·17H2O (SiW9Co3) was first studied due to its relatively smaller band gap (2.23 eV) and higher lowest unoccupied molecular orbital (LUMO) level (−0.63 V vs NHE). Additionally, the preliminary computational modeling indicated that SiW9Co3 exhibited the donor–acceptor (D–A) structure, in which the cobalt oxygen clusters and tungsten skeletons act as the electron donor and electron acceptor, respectively. By employing SiW9Co3 to modify the TiO2 film, the visible photovoltaic and photocurrent response were both enhanced, and the light-induced photocurrent at 420 nm was improved by 7.1 times. Moreover, the highly dispersive and small sized SiW9Co3 nanoclusters loading on TiO2 were successfully achieved by fab...

SiW11V/graphene nanocomposite was first prepared and introduced into TiO2 film. It showed a significant photocurrent response, which can be attributed to the photoinduced electrons of SiW11V. This work provides a promising strategy for exploring POMs sensitizers with lower energy levels than the CB of TiO2.

In this paper, we load TiO2 on the surface of the tri-pyridine-ruthenium heteropolytungstate [Ru(bipy)3]2[SiW12O40]·2C2H5OH·8H2O (1), which is mixed with P25 powder to get photoanode material and then adsorb N719 dyes to assemble a dye-sensitized solar cell. It is important that the performance of the DSSCs with 1-doped TiO2 (1 @ TiO2) is superior to ones with H4SiW12O40-doped TiO2 ({SiW12} @ TiO2), although their photoelectric conversion efficiencies are both higher than pure P25-based cells. The investigation of the EIS shows that 1 @ TiO2 can restrain charge recombination and doping the transition metal ruthenium improves the performance of the cell. The photovoltaic performance of the cell is enhanced and the short-circuit photocurrent density (Jsc) is as high as 16.272 mA cm− 2, which is 20.4% higher than pure P25-based cells and 4.4% higher than the {SiW12} @ TiO2-based cells under simulated AM 1.5 irradiation.

The high-nuclear cluster compound Na48[HxMo368O1032(H2O)240(SO4)48]·ca.1000H2O (denoted as {Mo368}) represents the known nanoscale hedgehog-type cluster anion with the diameter of approximately 6 nm. Herein, a TiO2@{Mo368} composite was prepared through a sol–gel process for the first time. SEM, XPS, and UV–vis spectra were employed to characterize their chemical composition and structures. Meanwhile, the as-obtained composite was further mixed with P25 (Degussa P25 titania photocatalyst) then applied as the photoanodes of dye-sensitized solar cells (DSSCs); the results showed that DSSCs with the P25-TiO2@{Mo368}-based photoanodes exhibited better performance than that with pure P25-based photoanodes, which was due to less carrier recombination and longer electron lifetime in the former DSSCs by the results from analysis of dark current measurement, electrochemical impedance spectroscopy, and open-circuit voltage decay curve.

This work aimed to study a novel transgenic expression system of the CD/TK double suicide genes enhanced by the nuclear matrix attachment region (MAR) for gene therapy. The recombinant vector pMS-CD/TK containing the MAR-survivin promoter-CD/TK cassette was developed and transfected into human gastric cancer SGC-7901 cells. Expression of the CD/TK genes was detected by quantitative real-time PCR (qPCR) and Western blot. Cell viability and apoptosis were measured using the methyl thiazolyl tetrazolium (MTT) assay and flow cytometry. When the MAR fragment was inserted into the upstream of the survivin promoter, the qPCR result showed that the expression of the CD/TK genes significantly increased 7.7-fold in the transgenic SGC-7901 cells with plasmid pMS-CD/TK compared with that without MAR. MTT and flow cytometry analyses indicated that treatment with the prodrugs (5-FC+GCV) significantly decreased the cellular survival rate and enhanced the cellular apoptosis in the SGC-7901 cells. The expression of the CD/TK double suicide genes driven by the survivin promoter can be enhanced by the MAR fragment in human gastric cancer cells.

ZnO nanoparticles (NPs) containing H3PW12O40 polyoxometalates (POMs) were firstly synthesized by a simple solvothermal route. The photoanodes of dye-sensitized solar cells (DSSCs) were assembled with the as-prepared ZnO powder containing H3PW12O40. A comparative experiment in the absence of POMs was carried out to investigate the influence of H3PW12O40. Furthermore, the effects of other Keggin-type POMs including W series, Mo series, and the potassium salt K3PW12O40 were studied and different concentrations of H3PW12O40 were utilized to investigate the impact on the performance of DSSCs on the basis of the above research. The results demonstrate that the W-containing POM series HxMW12O40 (M = P, x = 3; M = Si, Ge, x = 4) significantly enhances the performance of DSSCs by increasing electronic lifetimes and reducing dark currents. The overall solar-to-electric energy conversion efficiency reached a maximum of 2.70 % in the presence of H3PW12O40, which is an improvement of 49.2 % compared to the efficiency without H3PW12O40. A suitable H3PW12O40 concentration is crucial.

The efficacy and safety of polaprezinc combined with triple therapy was compared with triple therapy alone in the eradication of Helicobacter pylori. A randomized, parallel-group, open-label, controlled, prospective multicenter study was conducted in 11 cities in China. Treatment-naive patients with H. pylori–associated gastritis were randomly assigned to one of three arms for a 14-day treatment: Arm A triple therapy (omeprazole 20 mg, amoxicillin 1 g, and clarithromycin 500 mg, each twice daily) plus polaprezinc 75 mg twice daily; Arm B triple therapy plus polaprezinc 150 mg twice daily, or Arm C triple therapy alone. The rate of H. pylori eradication was the primary endpoint. Secondary endpoints were symptom improvement and lower incidence of adverse events. 303 patients completed the study– 106, 96, and 101 patients in Arms A, B, and C, respectively. Intention-to-treat (ITT) analysis showed that the rate of H. pylori eradication was significantly higher for Arms A (77.0%) and B (75.9%) compared to Arm C (58.6%) (P < 0.01), whereas there was no difference between Arms A and B (P = 0.90). Per-protocol (PP) analysis showed that the rate of H. pylori eradication was significantly higher for Arms A (81.1%) and B (83.3%) compared to Arm C (61.4%) (P < 0.01), whereas there was no significant difference between Arms A and B (P = 0.62). All three groups reported significant symptom improvement at 7, 14, and 28 days after treatment, compared to baseline (P < 0.0001). The adverse event rate for Arm B (5.1%) was higher than for Arms A (2.8%) (P = 0.04) and C (1.9%) (P = 0.02). There were no serious adverse events in any group. It appears that standard dose polaprezinc combined with triple therapy can significantly improve the H. pylori eradication rate, without an increase in toxicity.

The paper analyzed the sulfur in steel for civil engineering in 150t converter in TangSteel. Based on the analysis of desulfurization process and the thermodynamic conditions in converter, the operation of desulfurization was optimized. The industrial tests for desulfurization were carried out, and the results were analyzed. The results were shown that the distribution coefficient would be the highest value, when the alkalinity of slag was 3.5 and the FeO content was 21% in making SPHD steel. The distribution coefficient would reduce, when the temperature was increased, especially more than 1700°C, so end point temperature should be best less than 1700°C.

Combining with the production experience in steel making and rolling plant, the oxide inclusions of IF steel were investigated. In the operation process, the inclusions of IF steel are main Al2O3-TiN. They are granular and dispersed in the steel, and most of sizes are 1~5μm. In the inclusion center, the Al2O3 plays the role of TiN heterogeneous nucleation center. So reducing the Al2O3 inclusion is essential to stabilize the Ti content and strengthen the fixtation to C and N in steel. The quantity of Al2O3 inclusion was closely relation to the operation process. The Al2O3 inclusions can be significantly reduced by taking some measure.

Two new carboxyethyltin-functionalized polyoxometalates (POMs) were successfully obtained and confirmed with physicochemical and spectroscopic methods including X-ray crystallography. The lowest unoccupied molecular orbitals of both compounds are higher in energy than that of TiO2 , and the optical band gaps of these compounds are smaller than that of TiO2 . Grafting them onto a TiO2 film created two kinds of novel photoanode materials that showed significantly enhanced photovoltaic and photocurrent responses, as well as improved photoelectrooxidation activities for methanol relative to that shown by a single TiO2 film. Further, P2 W15 -Co-SnR produced the largest photocurrent by exploring the photoelectric activities of a series of carboxyethyltin POM derivatives. This work provides new insight into the photoelectrochemical functionalization of POM-based organic-inorganic hybrids.

By employing elemental analysis, 31P NMR, pH, and conductivity measurements, the protonated state of lacunary heteropolyoxotungstophosphates in aqueous solution, {PW11O39}, is determined to be [H3PW11O39]4−. Using it as ligand, a complex of [Ag(H2O)(H3PW11O39)]3− is formed. An electrochemical cell is designed as follows: (−) Hg, Hg2Cl2 [Ag(H2O)(H3PW11O39)]3− (aq) | Ag(s) (+) (salt bridge is saturated KNO3 solution). By measuring the electromotive force of the cell, the stability constant of [Ag(H2O)(H3PW11O39)]3− in aqueous solution is determined to be 4.34 × 103 (25 °C).

A supercapacitor electrode assembled from activated carbon and (NH4)6 [P2Mo18O62]·14.2H2O shows remarkable electrochemical performance.

Objective To study the effects of Naomaitong Recipe, a compound Chinese herbal medicine, on the expressions of nuclear factor-kappaB (NF-kappaB) and nitric-oxide synthases (NOSs) in brain tissue after focal cerebral ischemia reperfusion in aged rats and the dosage-effect relationship. Methods We adopted the middle cerebral artery occlusion (MCAO) in aged rats as the focal cerebral ischemia model, with 3-hour ischemia and 12-day reperfusion, and observed the changes of the nerve dysfunction score, the water content of cerebral constitution and the expressions of NF-kappaB, heat-shock protein 70 (HSP70) and NOSs in cerebral cortex. Results The nerve dysfunction score, the water content of cerebral constitution, the expressions of NF-kappaB, HSP70, neuronal nitric-oxide synthase (nNOS), endothelial nitric-oxide synthase (eNOS) and inducible nitric-oxide synthase (iNOS) in the untreated group were higher than those of the sham-operated group. The nerve dysfunction score, the water content of cerebral constitution, the expressions of NF-kappaB, iNOS and nNOS were lower, while the expressions of HSP70 and eNOS were higher in the high-, medium- and low-dose Naomaitong-treated groups and nimodipine-treated group than those of the untreated-group. The nerve dysfunction score and the expression of nNOS were lower, while the expression of eNOS was higher in the medium-dose Naomaitong-treated group than those of the nimodipine-treated group. The expressions of HSP70 and eNOS were higher, while the other indices were lower in the medium-dose Naomaitong-treated group than those of the low-dose Naomaitong-treated group. Conclusion Naomaitong Recipe can protect the brain cells from damage after focal cerebral ischemia reperfusion injury by adjusting the expressions of NF-kappaB, HSP70 and NOSs, and the medium-dose Naomaitong Recipe is more effective.

The ultrathin multilayer films of sphere-shaped polyoxomolybdate Mo 8 V 2 O 28 ·7H 2 O (abbreviated to Mo 8 V 2 ) and poly(allylamine hydrochloride) (DAH) have been prepared by the layer-by-layer (LbL) self-assembly method. The (Mo 8 V 2 /DAH) m multilayer films have been characterized by X-ray photoelectron spectra (XPS) and atomic force microscopy (AFM). The electrochemistry behavior of the film at room temperature was investigated.

Two novel open-chain carboxyethyltin decorated sandwich-type germanotungstates have been successfully synthesized. They could markedly increase the electrocatalytic activity of single-walled carbon nanotubes toward triiodide reduction when assembled into composite electrodes, which have shown a conversion efficiency of 6.32% that is comparable to that of Pt electrodes (6.29%) when used as counter electrodes in dye-sensitized solar cells.

Versican, a large extracellular matrix proteoglycan, accumulates both in tumor stroma and cancer cells. It participates in cell adhesion, migration, and angiogenesis, all features of invasion and metastasis. However, the mechanism(s) whereby versican promotes cancer invasion and metastasis is not yet fully understood. A recent study has documented that versican can activate tumor-infiltrating myeloid cells through toll-like receptor (TLR) 2 and its co-receptors TLR6 and CD14 and elicit the production of proinflammatory cytokines including TNF-alpha that enhance tumor metastasis. As both resident fibroblasts and endothelial cells (ECs) also express functional TLR2 and its co-receptors, we hypothesized that, in addition to myeloid cells, versican may trigger the activation of both fibroblasts and ECs. Of interest, TLR2-mediated activation of EC and fibroblast has been observed to increase the secretion of interleukin-8, a proinflammatory CXC chemokine that potentiates neutrophil infiltration and angiogenesis, as well as metastatic growth. Ligation of TLR2 by versican appears to be directly involved in the activation of multiple types of cells in tumor stroma and the induction of inflammatory cytokine secretion, providing a link between inflammation and cancer metastasis. Accordingly, antagonists of versican and TLR2 restrain the activation of tumor stromal cells, which may offer a novel approach to cancer therapy by targeting tumor microenvironment.

A comparative oral pharmacokinetic study of five anthraquinones (aloe-emodin, emodin, rhein, chrysophanol and physcion) from the extract of Rheum palmatum L. was performed in normal and thrombotic focal cerebral ischemia (TFCI)-induced rats. The plasma samples were clarified through solid phase extraction prior to simultaneous determination of the anthraquinones with a validated high-performance liquid chromatography-fluorescence system. The results indicated that the Cmax, t(1/2) and AUC(0-t), of aloe-emodin, rhein, emodin and chrysophanol in TFCI-induced rats were nearly double, whereas the CL values were remarkably decreased (p < 0.05) over those of the normal rats. The plasma drug concentration-time data of five anthraquinones to rats fitted a two-compartment open model. The five anthraquinones in rat plasma were absorbed quickly and eliminated slowly in both groups. The obtained results could be helpful for evaluating the impact of the efficacy and safety of the drug in clinical applications.

Background/aims Radiofrequency ablation (RFA) is a new treatment which is used to treat hepatocellular carcinoma (HCC). We performed this clinical trial to investigate whether it could reduce the damage of residual liver function. Methodology We studied 40 hepatitis-related chronic patients who underwent RFA for hepatocellular carcinoma. Indocyanine green (ICG) test was performed pre and postoperatively. Results There were 32 males and 8 females with an average age of 53.98+12.59 years who underwent RFA for HCC. The mean preoperative ICGR15 value of 40 of the patients was (10.17+9.54) lower than the postoperative ICG retention rate at 15 min (ICGR15) value (14.95+12.71).Differences between the preoperative ICGR15 and the postoperative ICGR15 values were not significantly different (p=0.074). The 1-, 2- and 3-year survival rates were 98.7%, 88.8% and 76.4%, respectively. Conclusions The results indicate that RFA is a minimally invasive treatment which provides a possible treatment modality for HCC patients with poor liver function and the efficacy is as well as the surgical treatment for HCC patients within the Milan criteria.

Background : To investigate the feasibility of detecting methylated tissue factor pathway inhibitor (TFPI2) and quantifying human long DNA with fluorescent quantitative Alu PCR in fecal DNA as a non-invasive screening tool for colorectal cancer (CRC). Materials and Methods : Methylation-specific PCR (MSP) was performed to analyze TFPI2 gene promoter methylation status in a blinded fashion in stool samples taken from 30 endoscopically diagnosed healthy controls, 20 patients with adenomas, and 60 patients with colorectal cancer. Real-time Alu PCR was used to quantify human long DNA. Results : The specificity of fecal TFPI2 MSP assay and long DNA assay was 100% and 83.3%, respectively. The sensitivity of fecal TFPI2 MSP assay and long DNA assay was 68.3% and 53.3%, respectively. The sensitivity of fecal DNA assay (either marker being positive) was 86.7%, which was high for CRC. Conclusions : Our results have demonstrated the feasibility of using TFPI2 methylation and quantify human long DNA with fluorescent quantitative Alu PCR in fecal samples as a new noninvasive test for CRC.

BACKGROUND AND OBJECTIVE S-adenosylmethionine (SAM), the most important methyl donor in human body, is generally used to treat cholestasis in clinic. In recent years, SAM has been found to have inhibitory effects on breast cancer, liver cancer and colon carcinoma. This study was to investigate the inhibitory effects of SAM on human gastric cancer cells in vivo and in vitro, and the antitumor mechanisms. METHODS The effects of SAM on the proliferation of gastric cancer SGC-7901 and MKN-45 cells were determined by MTT assay. After SGC-7901 and MKN-45 cells were treated with 0, 2, and 4 mmol/L SAM for 72 h, the expression and methylation of c-myc and urokinase type plasminogen activator (uPA) were detected by reverse transcription-polymerase chain reaction (RT-PCR) and methylation-specific PCR (MSP). Tumor xenografts were established by injecting SGC-7901 cells subcutaneously in BALB/c nude mice. The mice were randomized into low concentration group [192 µmol/(kg · day)], high concentration group [768 µmol/(kg · day)], and control group [normal saline (NS)], and received peritoneal injection of relative reagents for 15 days. The tumor size was measured, the protein and mRNA expression of c-myc and uPA were detected by immunohistochemistry and RT-PCR, and the methylation of c-myc and uPA genes was detected by MSP. RESULTS SAM inhibited the growth of SGC-7901 and MKN-45 cells obviously and the effects were enhanced with the increase of SAM concentration and treatment time. The mRNA expression of c-myc and uPA in SGC-7901 cells and that of uPA in MKN-45 cells significantly decreased. The c-myc and uPA genes in SGC-7901 cells and uPA gene in MKN-45 cells were partly or completely methylated after SAM treatment. The tumor volume was significantly lower in low concentration group [(618.51 ± 149.27) mm³] and high concentration group [(444.32 ± 118.51) mm³] than in control group [(1018.22 ± 223.07) mm³] (both P < 0.01). The inhibitory rates of tumor growth were 39.26% in low concentration group and 56.36% in high concentration group. The protein and mRNA expressions of c-myc and uPA were remarkably reduced (all P < 0.01), and the hypomethylation of c-myc and uPA genes were reversed after SAM treatment. CONCLUSIONS SAM can inhibit the growth of human gastric cancer cells both in vivo and in vitro. The mechanism may be that SAM can reverse the hypomethylation of c-myc and uPA genes, reduce their expression, and then inhibit tumor growth.

To calculate the experimental data of indexes with computer through the multi-objective decision-making, and then to make the comprehensive evaluation of effects of different Chinese Medicines combined with Bone Mesenchymal Stem Cells(BMSCs) transplantation on cerebral ischemia rats based on analytic hierarchy process(AHP). BMSCs were implanted via rats carotid artery. Rats general neural function, cerebral infarction size and brain water ratio were detected and weights of indexes were calculate by using AHP. Weight of Rhubarb aglycone was the largest in 1 w groups. In 2 w groups, Naomaitong was the largest. In 4 w groups, Rhubarb aglycone and Naomaitong combined with BMSCs transplantation were larger. It was indicated that It was feasible to make a comprehensive evaluation of effects through comparing weight indexes of experimental data by using AHP, and the combination of Chinese medicines and BMSCs transplantation showed more significant effects following the prolongation of BMSCs transplantation.

Occurrence of second primary tumors and metastasis remains the major obstacles to prolonged survival of patients with primary hepatocellular carcinoma (HCC). A somatostatin analogue, octreotide, has been previously reported to inhibit the growth of human HCC xenografts in nude mice through its anti-angiogenic activity. It is therefore important to investigate whether octreotide could prevent second primary hepatomas or distant metastasis following resection of primary HCC. In this study, nude mice, bearing the human HCC xenografts with highly metastatic potential (LCI-D20) in the left liver lobe, underwent tumor resection, and received intraperitoneal administration of octreotide or saline as a control for 35 consecutive days. Compared with the control group, octreotide at the doses of 100 and 200 microg/kg/day significantly inhibited the growth (P < 0.001 and P < 0.001, respectively) and incidence of second primary tumors (P = 0.016 and P = 0.001, respectively), decreased lung metastasis (P < 0.001 and P < 0.001, respectively), and prolonged the life span (P = 0.029 and P = 0.006, respectively). Moreover, intratumoral angiogenesis quantified by microvessel density as well as serum and tissue vascular endothelial growth factor (VEGF) levels were considerably decreased in octreotide-treated animals compared to the control animals. These findings suggest that octreotide may prevent the occurrence of second primary hepatomas and lung metastasis after resection of primary HCC, which may be partially attributed to down-regulation of VEGF and subsequent reduction in tumor angiogenesis. Octreotide administration may be useful as an adjuvant therapy to improve survival of patients with HCC.

An experimental rat hepatocellular carcinoma (HCC) model was established using diethylnitrosamine and N-nitrosomorpholine to induce carcinogenesis in Sprague-Dawley rats. During hepatocarcinogenesis, seven rats were sacrificed at 0, 4, 8, 12 and 16 weeks and 10 rats were sacrificed at 20 weeks. The levels of hypoxia-inducible factor-1alpha (HIF-1alpha) and vascular endothelial growth factor (VEGF) protein and mRNA were examined by immunohistochemistry, Western blot and semi-quantitative reverse transcriptase-polymerase chain reaction at different stages in the rat HCC model. Twenty weeks after induction of hepatocarcinogenesis, the expression of HIF-1alpha and VEGF protein and mRNA significantly increased compared with week 0. Microvessel density (MVD) increased considerably once liver cancer developed. There was a significant positive correlation between MVD and both HIF-1alpha and VEGF, and between HIF-1alpha and VEGF levels. These results suggest that HIF-1alpha and VEGF play important roles in tumour occurrence and development during rat hepatocarcinogenesis, possibly through promoting tumour angiogenesis.

Background Esophageal carcinoma is a common kind of malignant tumor and about 90% of which is esophageal squamous cell carcinoma (ESCC), and it has a high incidence in China. In recent years it has been argued that angiogenesis plays a key role in tumor growth and metastasis and it is a complex process influenced by many factors. This study was aimed to investigate the expression of PC cell-derived growth factor (PC DGF or progranulin) and vascular endothelial growth factor (VEGF) in ESCC tissue and their relationship with clinical pathological parameters of ESCC, clarify the role of PCDGF and VEGF in the angiogenesis of ESCC. Methods The expression of PCDGF and VEGF in 50 surgical specimens from patients with ESCC and 20 with normal esophageal mucosa were detected by immunohistochemistry. The vascular endothelial cells in tumor tissues were labeled by antibody to CD105 for counting microvessel density (MVD). Results The expression of PCDGF and VEGF in ESCC was significantly higher than that in normal mucosa. Expression correlated with the depth of tumor invasion, lymph node metastasis, and TNM (classification tumor, nodes, metastasis). In ESCC, both the expression level of PCDGF and VEGF had a positive correlation with MVD and the expression of PCDGF had a significant correlation with the expression of VEGF. Conclusions These results show that both of PCDGF and VEGE have higher expression in ESCC, which indicate that they have a close relationship with angiogenesis. They may be involved in tumor growth, infiltration and metastasis through promoting tumor angiogenesis and may be an important index reflecting biological behavior and prognosis of ESCC.

OBJECTIVE To observe the effects of rhubarb aglycone on pathological changes and activity of matrix metalloproteinase in cerebral ischemic tissue in rats with bone marrow mesenchymal stem cell (BMSC) transplantation, and to explore the action mechanisms of rhubarb aglycone in protecting against brain micrangium injury in rats. METHODS The BMSCs were purified and amplified by methods of adherence and selection in vitro. One hundred and ninety rats were randomly divided into sham-operated group, untreated group, rhubarb aglycone group, BMSC transplantation group (abbreviated as transplantation group) and BMSCs combined with rhubarb aglycone group (abbreviated as combination group). Middle cerebral artery occlusion (MCAO) model was duplicated with nylon thread. Rats of transplantation and combination group were transplanted with BMSCs via carotid artery after 24-hour reperfusion. Rhubarb aglycone was used by intragastric administration in the rhubarb aglycone group and the combination group. The brain samples were taken at 7, 14 and 28 days after transplantation. Brain micrangium pathological changes were observed by light microscope, and immunohistochemical method was used to determine the expressions of immunoglobulin G (IgG), type IV collagen (Col IV), matrix metalloproteinase-9 (MMP-9), and tissue inhibitor of metalloproteinase-1 (TIMP-1). RESULTS Comparison with the normal control group revealed that brain micrangium in rats in the untreated group was obviously mutilated and damaged, the expression of IgG and MMP-9 increased, and showed a progressively enhanced tendency following the prolongation of reperfusion, while the expressions of Col IV and TIMP-1 were decreased, and TIMP-1 showed a attenuated tendency following the prolongation of reperfusion. Comparing with the untreated group, the improvements of brain micrangium structure in the rhubarb aglycone group (7 days after transplantation), the transplantation group (14 and 28 days after transplantation) and the combination group were significant; expression of IgG and activity of MMP-9 were decreased, while expressions of Col IV and TIMP-1 were increased in the rhubarb aglycone group and the combination group at each time point. The brain micrangium was integral and the expression of Col IV was enhanced in combination group (7 days after transplantation) as compared with those in transplantation group. MMP-9 activity in combination group (14 days after transplantation) was lower than that in the rhubarb aglycone group (14 days after transplantation), while expression of TIMP-1 in combination group also increased significantly as compared with that in transplantation group (28 days after transplantation). CONCLUSION Rhubarb aglycone can decrease the degradation of basal lamina Col IV and the permeability of brain micrangium in cerebral ischemic rats with BMSC transplantation, and its mechanisms may be related to regulating the balance of MMP-9, especially by increasing the expression of TIMP-1.

OBJECTIVE: To determine the inhibitory effects of all-trans-retinoic acid (ATRA) on cell growth, cell cycle and vascular endothelial growth factor (VEGF) expression in the human gastric cancer cell line BGC-823 in vitro. METHODS: Human gastric cancer BGC-823 cells were treated with various concentrations of ATRA and the cell growth was then determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide viability assay. The cell cycle distribution was analyzed using a flow cytometer. The VEGF mRNA and protein expression were analyzed by semi-quantitative RT-PCR and Western blotting, respectively. RESULTS: ATRA at concentrations of 0.1–10 µmol/L inhibited the growth of BGC-823 cells grown in culture; a time- and dose-dependent inhibitory influence was found. ATRA arrested BGC-823 cells at the G0/G1 phase in a dose-dependent way. Both VEGF mRNA and protein were decreased by ATRA in a dose-dependent way. CONCLUSION: The anti-tumor effects of ATRA on human gastric cancer cells are associated with G0/G1 phase arrest and decreased VEGF expression.

To investigate the effect of octreotide on angiogenesis induced by human hepatocellular carcinoma (HCC) and to evaluate whether octreotide can suppress tumor growth in nude mice bearing human HCC xenografts through inhibition of angiogenesis. Using MTT assay, invasion assay, migration assay, and Matrigel assay, the effects of octreotide on endothelial cells stimulated by vascular endothelial growth factor (VEGF) were evaluated in vitro. MTT assay was also used to investigate the effects of octreotide on human HCC cells with high (MHCC97-H) and low (MHCC97-L) metastatic potential that were established from the animal model of human HCC LCI-D20 in nude mice. The expression of somatostatin receptor (SSTR) subtypes in human umbilical vein endothelial cells (HUVECs), MHCC97-H, and MHCC97-L cells was detected by RT-PCR analysis. An LCI-D20 corneal micropocket model in nude mice was used to evaluate the effect of octreotide on angiogenesis induced by human HCC in vivo. Male nude mice were subcutaneously implanted with LCI-D20 tumor tissues for the tumor xenograft studies. Microvessel density was analyzed in CD34-stained tumor sections by the immunohistochemical SP method. In vitro, octreotide inhibited the proliferation, invasion, and differentiation of HUVECs elicited by VEGF. RT-PCR analysis demonstrated that HUVECs expressed the somatostatin receptor subtype SSTR3. In vivo, octreotide was sufficiently potent to suppress nude mice corneal neovascularization induced by tumor tissues from LCI-D20. Systemic administrations of octreotide produced a significant suppression of the growth of LCI-D20. In cell culture, MHCC97-H and MHCC97-L cells were insensitive to octreotide at concentrations that significantly inhibited endothelial cells proliferation. The HCC cells used did not express any known SSTRs. Immunohistochemical studies of tumor tissues revealed decreased microvessel density in octreotide-treated animals as compared with controls. The present study demonstrates that the somatostatin analogue octreotide is a potent antitumor angiogenesis compound and the antiproliferative effect of octreotide on tumor growth in nude mice bearing HCC xenografts may be mediated, at least in part, by its suppressive effect on blood vessel supply. The somatostatin analogue octreotide might provide a useful and relatively nontoxic adjuvant therapy in the treatment of HCC.

Based on the time-dependent coincidence method, a preliminary experiment has been performed on uranium metal castings with similar quality (about 8–10 kg) and shape (hemispherical shell) in different enrichments using neutron from Cf fast fission chamber and timing DT accelerator. Groups of related parameters can be obtained by analyzing the features of time-dependent coincidence counts between source-detector and two detectors to characterize the fission signal. These parameters have high sensitivity to the enrichment, the sensitivity coefficient (defined as (ΔR/Δm)/R) can reach 19.3% per kg of 235U. We can distinguish uranium castings with different enrichments to hold nuclear weapon verification.