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Purpose This study aimed to explore the regulatory mechanism of the natural soda Shi Han Quan (SHQ) in the development of gout. Methods Human umbilical vein endothelial cells (HUVECs) were stimulated with monosodium urate (MSU) for 24 h to induce acute gouty inflammation in vitro. HUVECs were divided into four groups: ddH2O group, ddH2O + MSU group, 1/2 ddH2O +1/2 SHQ + MSU group, and SHQ + MSU group. The effects of SHQ on cell viability, concentration and expression of intercellular adhesion molecule-1 (ICAM-1), and MSU-induced release of interleukin (IL)-1β and IL-6 were investigated. Additionally, cell viability and ICAM-1 concentration and expression were detected after HUVECs were incubated with the culture supernatant of THP-1 cells that had been treated with phorbol 12-myristate 13-acetate (PMA), MSU and SHQ for 24 h. Results The viability of HUVECs was significantly decreased with increasing transfection concentrations of MSU, and MSU treatment resulted in a significant increase of the concentration and expression of ICAM-1. In addition, SHQ improved the MSU-induced decrease in cell viability and alleviated MSU-mediated increase in ICAM-1 levels. Moreover, SHQ decreased MSU-induced release of IL-1β and IL-6. After HUVECs were incubated with the culture supernatant of THP-1 cells that had been treated with PMA, MSU and SHQ for 24 h, SHQ also markedly alleviated the effects of MSU, such as by increasing cell viability and decreasing ICAM-1 levels. Conclusions Drinking natural soda water may have a significant role in preventing gouty inflammation. more...

A series of dithiocarbamate-3-epi-jaspine B hybrids have been designed and synthesized from D-xylose based on the introduction of long lipophilic alkyl dithiocarbamate moieties at the C4 position of 3-epi-jaspine B. The anticancer activities of these compounds have been evaluated against two selected tumor cell lines (MGC-803 and B16-F10 cells), with most of the synthesized compounds exhibiting moderate activity. Among them, compounds 20d and 20f showed the highest levels of inhibitory activity of all the compounds tested against MGC-803 and B16-F10 cells with IC50 values of 16.39 and 14.83 µM, respectively. This work therefore represents the first reported account of the synthesis and in vitro cytotoxic evaluation of dithiocarbamate-3-epi-jaspine B hybrids. more...

Gout is a genetic or acquired metabolic disease caused by increase of uric acid synthesis resulted from purine metabolic abnormalities. Whether cGMP-dependent protein kinase 2 (cGKII/PRKG2) is correlated with gout remains controversial. The objective of the present study was to investigate whether there is a correlation between polymorphism of cGKII/PRKG2 and gout susceptibility of Han population in northern China. Four hundred and five male patients with gout in the case group and 429 controls in the control group were collected from the Department of Endocrinology and Metabolic Disease, the Fourth Affiliated Hospital of Harbin Medical University. A case-control study method was used to study the correlation between cGKII/PRKG2 polymorphism rs7688672 and rs10033237 and gout susceptibility. The genotype frequencies of rs7688672 and rs10033237 polymorphisms of cGKII/PRKG2 in the case group and the control group both were in accordance with Hardy-Weinberg equilibrium. There were significant differences of rs10033237 in the allele frequencies and genotype distributions (P more...

Electrochemical impedance spectroscopy (EIS) for the initial Li-ion insertion and extraction in Li4Ti5O12 (LTO) anode at different potentials were studied. At the intermediate stage of Li-ion insertion process, as the frequency decreased, the EIS spectra exhibited three semicircles and a slightly inclined line, which correspond to the Schottky contact reflecting the electronic properties of the material, the charge transfer step and solid state diffusion process respectively. At the intermediate stage of Li-ion extraction process, it was observed that the low-frequency semicircle turned into two joint semicircles. This interesting and significant phenomenon was attributed to gas generation in LTO cells. Kinetic parameters obtained from fitting the experimental impedance spectra in the first charge–discharge cycle on LTO side have been analyzed in detail. A new model was proposed to interpret the mechanism of Li-ion insertion/extraction reaction along with side reactions (gas generation) in the LTO electrode. more...

The possible reasons and key factors on gas generation of Li 4 Ti 5 O 12 (LTO) cells are investigated by the accelerating measurement baking at 80 °C for 120 h. It is found that the chemically catalytic reaction related to moisture makes a minor contribution to cell swelling. Our LTO-based 383450 cells (∼10 mL) before pre-charge (i.e. formation) only produce ∼1.5 mL gas during baking test and CO 2 , instead of H 2 , is the dominant species in EC/DMC electrolyte. By contrast, the swelling ratio of the charged LTO cells, which are re-sealed after formation, is kept at ∼97% regardless of states of charge. This severe decomposition of carbonates at elevated temperature should be dominated by the anode potential, rather than catalysis of LTO, since graphite/NMC cells show a similar swelling behavior at over-discharge state, where graphite anode shares the same potential as LTO. On the other hand, the electrolyte stability is also dependent on the type of solvent. Among the investigated systems, the mixture of PC + DMC (1:1) exhibits the best behavior to suppress the cell swelling. The swelling ratio diminishes from ∼100% of other electrolytes to 50%. This improvement probably roots in the high quality of protective films formed during solvents' decomposition. more...

The formation process of solid electrolyte interphase(SEI) film on spinel LiMn2O4 electrode surface was studied by electrochemical impedance spectroscopy(EIS) during the initial storage in 1 mol/L LiPF6-EC:DMC:DEC electrolyte and in the subsequent first charge-discharge cycle. It has been demonstrated that the SEI film thickness increased with the increase of storage time,and spontaneous reactions occurring between spinel LiMn2O4 electrode and electrolyte can be prevented by the SEI film. In the first charge-discharge cycle succeeding the storage, the electrolyte oxidation coupled with Li-ion insertion is evidenced as the main origin to increase the resistance of SEI film. The results also confirm that the variations of the charge transfer resistance(Rct) with the electrode potential(E) can be well described using a classical equation. Keywords Li-ion batteries; SEI film; Electrochemical impedance spectroscopy; Spinel LiMn2O4 more...

Functionalized molecular sieve SBA-15 with trimethylchlorosilane was used as an inorganic filler in a poly(ethyleneoxide) (PEO) polymer matrix to synthesize a composite solid-state polymer electrolyte (CSPE) using LiClO4 as the doping salts, which is designated to be used for rechargeable lithium batteries. The methyl group-functionalized SBA-15 (fSBA-15) powder possesses more hydrophobic characters than SBA-15, which improves the miscibility between the fSBA-15 filler and the PEO matrix. The interaction between the fSBA-15 and PEO polymer matrix was investigated by scanning electron microscopy, X-ray diffraction, and differential scanning calorimetry. Linear sweep voltammetry and electrochemical impedance spectroscopy were employed to study the electrochemical stability windows, ionic conductivity, and interfacial stability of the CSPE. The temperature dependence of the change of the PEO polymer matrix in the CSPE from crystallization to amorphous phase was surveyed, for the first time, at different temperature by Fourier transform infrared emission spectroscopy. It has demonstrated that the addition of the fSBA-15 filler has improved significantly the electrochemical compatibility of the CSPE with a lithium metal electrode and enhanced effectively the ion conductivity of the CSPE. more...

The storage behavior and the first delithiation of LiCoO2 electrode in 1 mol/L LiPF6-EC:DMC:DEC electrolyte were investigated by electrochemical impedance spectroscopy (EIS). It has found that, along with the increase of storage time, the thickness of SEI film increases, and some organic carbonate lithium compounds are formed due to spontaneous reactions occurring between the LiCoO2 electrode and the electrolyte. When electrode potential is changed from 3.8 to 3.95 V, the reversible breakdown of the resistive SEI film occurs, which is attributed to the reversible dissolution of the SEI film component. With the increase of electrode potential, the thickness of SEI film increases rapidly above 4.2 V, due to overcharge reactions. The inductive loop observed in impedance spectra of the LiCoO2 electrode in Li/LiCoO2 cells is attributed to the formation of a Li1−x CoO2/LiCoO2 concentration cell. Moreover, it has been demonstrated that the lithium-ion insertion-deinsertion in LiCoO2 hosts can be well described by both Langmuir and Frumkin insertion isotherms, and the symmetry factor of charge transfer has been evaluated at 0.5. more...

The storage behavior and process of the first delithiation-lithiation of LiCoO2 cathode were investigated by electrochemical impedance spectroscopy (EIS). The electronic and ionic transport properties of LiCoO2 cathode along with variation of electrode potential were obtained in 1 mol·L−1 LiPF6-EC:DMC: DEC electrolyte solution. It was found that after 9 h storage of the LiCoO2 cathode in electrolyte solutions, a new arc appears in the medium frequency range in Nyquist plots of EIS, which increases with increasing the storage time. In the charge/discharge processes, the diameter of the new arc is reversibly changed with electrode potential. Such variation coincides well with the electrode potential dependence of electronic conductivity of the LiCoO2. Thus this new EIS feature is attributed to the change of electronic conductivity of Li x CoO2 during storage of the LiCoO2 cathode in electrolyte solutions, as well as in processes of intercalation-deintercalationtion of lithium ions. It has been revealed that the reversible increase and decrease of the resistance of SEI film in charge-discharge processes can be also ascribed to the variation of electronic conductance of active materials of the LiCoO2 cathode more...

Molecular sieves of NaY, MCM-41, and SBA-15 were used as fillers in a poly(vinylidene fluoride- co -hexafluoropropylene) (PVdF-HFP) copolymer matrix to prepare microporous composite polymer electrolyte. The SBA-15-based composite polymer film was found to show rich pores that account for an ionic conductivity of 0.50 mS cm −1 . However, the MCM-41 and NaY composite polymer films exhibited compact structure without any pores, and the addition of MCM-41 even resulted in aggregation of fillers in the polymer matrix. These differences were investigated and interpreted by their different compatibility with DMF solvent and PVdF-HFP matrix. Results of linear sweep voltammetry (LSV), electrochemical impedance spectroscopy (EIS), X-ray diffraction (XRD) and differential scanning calorimetry (DSC) have revealed that the addition of SBA-15 has extended the electrochemical stability window of polymer electrolyte, enhanced the interfacial stability of polymer electrolyte with lithium electrode, and inhibited also the crystallization of PVdF-HFP matrix. Half-cell of Li/SBA-15-based polymer electrolyte/MCF was assembled and tested. The results have demonstrated that the coulombic efficiency of the first cycle was around 87.0% and the cell remains 94.0% of the initial capacity after 20 cycles, which showed the potential application of the composite polymer electrolyte in lithium ion batteries. more...

Electrocatalytic oxidation of carbon monoxide and methanol at Pt nanoparticles confined in mesoporous molecular sieve SBA-15 was studied by using cyclic voltammetry and in situ FTIR spectroscopy. Cyclic voltammetric studies revealed that the Pt nanoparticles confined in SBA-15 exhibit a high activity in the presence of hydrated phase consisting of SiO2 in the SBA-15. In situ FTIR spectroscopy results discovered that IR absorption of CO adsorbed on Pt nanoparticles confined in SBA-15 has been enhanced 11-fold, and the full-width at half-maximum of the CO band is significantly increased, in comparison with IR feature of CO adsorbed on a bulk Pt electrode. The linearly adsorbed CO species is the only intermediate derived from dissociative adsorption of methanol, which is more readily oxidized to form CO2 in the aid of the active oxide in SBA-15. more...

Two series of more available novel 1,2,3-triazole-Jaspine B hybrids were efficiently synthesized employing click chemistry approach and evaluated for their cytotoxic activities against three human cancer cell lines (EC-9706, MGC-803 and MCF-7). Among them, compound 14h showed excellent inhibition against MCF-7 (IC 50 = 1.93 μM) and was more potent than 5-Fu and Jaspine B against all three cancer cell lines. Further investigation of apoptosis assay and cell cycle analysis demonstrated that compound 14h caused cellular early and late apoptosis and arrested the cell cycle at G2/M phase in a concentration- and time-independent manner. This was the first report about the synthesis and in vitro cytotoxic evaluation of 1,2,3-triazole-Jaspine B hybrids. more...

The photoelectric behaviours of covalently linked porphyrin-donor-acceptor compounds: diad, triad, tetrad and porphyrin with C 16 alkyl substitute incorporated into molecular laver assemblies by LB film technique have been investigated. The photovoltages and photocurrents were measured and compared for monolayer of their LB films. The increase of photovoltages and photocurrents with the order tetrad > triad > diad > TPP-OC 16 H 33 indicates that the photoelectric behaviours can be improved successfully in the well designed porphyrin linked donor-acceptor compound systems. more...