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Asiatic acid (AA) is generally recognized in the treatment of various diseases and has significant advantages in the treatment of various inflammatory diseases. The treatment of rheumatoid arthritis (RA) with AA is a completely new entry point. RA is a complex autoimmune inflammatory disease, and despite the involvement of different immune and nonimmune cells in the pathogenesis of RA, fibroblast‐like synoviocytes (FLS) play a crucial role in the progression of the disease. si‐Nrf2 was transfected in RA‐FLS and the cells were treated with AA. MTT assay and colony formation assay were used to detect the effect of AA on the viability and formation of clones of RA‐FLS, respectively. Moreover, the apoptosis of RA‐FLS was observed by Hoechst 33342 staining and flow cytometry. Western blot was applied to measure the expression of the Nrf2/HO‐1/NF‐κB signaling pathway‐related proteins. Compared with the control group, RA‐FLS proliferation, and clone formation were significantly inhibited by the increase of AA concentration, and further experiments showed that AA‐induced apoptosis of RA‐FLS. In addition, AA activated the Nrf2/HO‐1 pathway to inhibit NF‐κB protein expression. However, the knockdown of Nrf2 significantly offsets the effects of AA on the proliferation, apoptosis, and Nrf2/HO‐1/NF‐κB signaling pathway of RA‐FLS cells. AA can treat RA by inhibiting the proliferation and inducing the apoptosis of RA‐FLS. The mechanism may be related to the activation of the Nrf2/HO‐1/NF‐κB pathway. [ABSTRACT FROM AUTHOR]

Emerging evidence suggests that miR‐143 plays an important role in the regulation of tumor sensitivity to chemotherapeutic agents. The study explores the underlying mechanism of miR‐143 in reversing cisplatin resistance in ovarian cancer. The cisplatin‐resistant ovarian cancer cell line A2780/CDDP was induced and established via treating A2780 cells by gradually increasing cisplatin concentrations. The IC50 values of A2780/CDDP and A2780 to cisplatin were 218.10 ± 1.12 and 21.99 ± 1.12 μM, respectively. Quantitative real‐time polymerase chain reaction (qRT‐PCR) results showed that miR‐143 was significantly decreased in A2780/CDDP cells compared with A2780 cells. miR‐143 overexpression decreased cisplatin resistance in A2780/CDDP, and miR‐143 inhibition decreased A2780 sensitivity to cisplatin. Results of qRT‐PCR, Western blot analysis, and luciferase reporter assay indicated that the direct target of miR‐143 was DNMT3A, which, in turn, was upregulated in A2780/CDDP. DNMT3A overexpression antagonized the sensitizing effect of miR‐143 on A2780/CDDP to cisplatin. Knocking down of DNMT3A reduced cisplatin resistance in A2780/CDDP, while overexpression of DNMT3A increased cisplatin resistance in A2780. Methylation‐specific polymerase chain reaction results showed that the methylation level in the promoter region of the miR‐143 precursor gene was higher in A2780/CDDP cells than in A2780 cells. DNMT3A mediated the hypermethylation of the miR‐143 precursor gene, resulting in miR‐143 downregulation in A2780/CDDP. miR‐143 inhibited cell growth of A2780/CDDP cell in nude mice. Our findings indicated the negative feedback between miR‐143 and DNMT3A as a crucial epigenetic modifier of cisplatin resistance in ovarian cancer. [ABSTRACT FROM AUTHOR]

Axial‐to‐central chirality transfer is an important strategy to construct chiral centers, where the axially chiral reagents are mostly limited to atropomerically stable ones. Reported herein is a RhIII‐catalyzed enantioselective spiroannulative synthesis of nitrones. The coupling proceeds via C−H arylation to give an atropomerically metastable biaryl, followed by intramolecular dearomative trapping under oxidative conditions with high degree of chirality transfer. [ABSTRACT FROM AUTHOR]

This paper reports electrocaloric effect (ECE) refrigeration with large cooling capacity in BaTiO3 ceramics near room temperature, which is repeated cycling near a first-order phase transition despite the hysteresis. ECE refrigeration is well manipulated by electric fields around the orthorhombic-tetragonal phase transition. After heating under an electric field of 5 kV cm−1 and removing the field at 14.5 °C, a large ECE cooling of 0.38 J g−1 (Δ T/ E=1.7 K m MV−1) is produced and recorded by direct heat-flow measurements. The cycle can be completed and repeated after cooling to 10.5 °C or lower temperatures and by applying electric fields. Stronger electric fields will induce a larger endothermic value over a wide temperature window. The large ECE value is also confirmed by quasidirect entropy change measurements, which further predict its variation under higher electric fields. [ABSTRACT FROM AUTHOR]

Forest litter exerts an impact on the energy budget of snow surfaces, which lie beneath forest canopies. In this study, we measured shortwave and longwave radiation levels, as well as quantities of Asian spruce ( Picea schrenkinan) forest litter, over 3 snow study plots that representing an open environment, 20% forest canopy openness (20% FCO), and 80% forest canopy openness (80% FCO). The fractional litter coverage ( lc) was obtained through the binarization of digital photographs of forest litter. The effects of forest litter on snow surface albedo ( α), snow surface temperature ( T s), upward shortwave and longwave radiation ( K↑ and L↑), and sensible heat flux ( H) were then analyzed. According to our results, the energy budget over snow surface influenced by forest litter principally due to forest litter forcing α decrease and T s increase. The effects of forest litter on the energy budget increased with time and lc. We found that forest litter exerted the most significant impact on K↑ and L↑ at daytime during the latter stages of the snowmelt period. The influence of forest litter on H was more apparent on windy days. The presence of forest litter increased gains in shortwave radiation and losses in longwave radiation and decreased gains in H. Compared to the simulated energy ( K↑ + L↑ + H) over a snow surface without litter, the calculated energy decreased by −13.4 W/m2 and increased by 9.0 W/m2, respectively, at the 20% FCO and 80% FCO sites during the latter stages of the snowmelt period. Overall, forest litter facilitated snow surface energy gains at the 80% FCO site and impeded them at the 20% FCO site during the latter stages of the snowmelt period. [ABSTRACT FROM AUTHOR]

The development of chemo-resistance impairs the outcome of the first line platinum-based chemotherapies for ovarian cancer. Deregulation of DNA methylation/demethylation provides a critical mechanism for the occurrence of chemo-resistance. The ten-eleven translocation (TET) family of dioxygenases including TET1/2/3 plays an important part in DNA demethylation, but their roles in cisplatin resistance have not been elucidated. Using cisplatin-sensitive and cisplatin-resistant ovarian cancer cell models, we found that TET1 was significantly upregulated in cisplatin-resistant CP70 cells compared with that in cisplatin-sensitive A2780 cells. Ectopic expression of TET1 in A2780 cells promoted cisplatin resistance and decreased cytotoxicity induced by cisplatin, while inhibition of TET1 by siRNA transfection in CP70 cells attenuated cisplatin resistance and enhanced cytotoxicity of cisplatin. Increased TET1 induced re-expression of vimentin through active DNA demethylation, and cause partial epithelial-to-mesenchymal (EMT) in A2780 cells. Contrarily, knocking down of TET1 in CP70 cells reduced vimentin expression and reversed EMT process. Immunohistochemical analysis of TET1 in human ovarian cancer tissues revealed that TET1 existed in nucleus and cytoplasm in ovarian cancer tissues. And the expression of nuclear TET1 was positively correlated with residual tumor and chemotherapeutic response. Thus, TET1 expression causes resistance to cisplatin and one of the targets of TET1 action is vimentin in ovarian cancer. [ABSTRACT FROM AUTHOR]

ABSTRACT Poly(1,5-diaminoanthraquinone) is synthesized by oxidative polymerization of diaminoanthraquinone monomers and investigated as an organic host for Li-storage reaction. Benefiting from its high density of redox-active, Li+-associable benzoquinone groups attached to conducting polyaniline backbones, this polymer undergoes its cathodic reaction predominately through Li+-insertion/extraction processes, delivering a very high reversible capacity of 285 mAh g−1. In addition, the PDAQ polymer cathode exhibits an excellent rate capability (125 mAh g−1 at 800 mA g−1) and a considerable cyclability with a capacity retention of ∼160 mAh g−1 over 200 cycles, possibly serving as a sustainable, high capacity Li+ host cathode for Li-ion batteries. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015, 53, 235-238 [ABSTRACT FROM AUTHOR]

Aqueous rechargeable sodium-ion batteries have the potential to meet growing demand for grid-scale electric energy storage because of the widespread availability and low cost of sodium resources. In this study, we synthesized a Na-rich copper hexacyanoferrate(II) Na2CuFe(CN)6 as a high potential cathode and used NaTi2(PO4)3 as a Na-deficient anode to assemble an aqueous sodium ion battery. This battery works very well with a high average discharge voltage of 1.4 V, a specific energy of 48 Wh kg−1, and an excellent high-rate cycle stability with approximately 90 % capacity retention over 1000 cycles, achieving a new record in the electrochemical performance of aqueous Na-ion batteries. Moreover, all the anode, cathode, and electrolyte materials are low cost and naturally abundant and are affordable for widespread applications. [ABSTRACT FROM AUTHOR]

Storable sunshine, reusable rays: A solar rechargeable redox flow battery is proposed based on the photoregeneration of I3−/I− and [Fe(C10H15)2]+/Fe(C10H15)2 soluble redox couples, which can be regenerated by flowing from a discharged redox flow battery (RFB) into a dye‐sensitized solar cell (DSSC) and then stored in tanks for subsequent RFB applications This technology enables effective solar‐to‐chemical energy conversion. [ABSTRACT FROM AUTHOR]

Vegetation phenology has a strong effect on terrestrial carbon cycles, local weather, and global radiation partitioning between sensible and latent heat fluxes. Based on phenological data that were collected from a typical steppe ecosystem at Xilingol Grazing and Meteorological Station from 1985 to 2003, we studied the phenological characteristics of Leymus chinensis and Stipa krylovii. We found that the dates for budburst of L. chinensis and S. krylovii were delayed with increasing temperature during winter and spring seasons; these results differed from existing research in which earlier spring events were attributed to the changes in increasing air temperature in winter and spring. The results also suggested that water availability was an important controlling factor for phenology in addition to temperature in grassland plants. The classical cumulative temperature model simulated the phenology well in wet years, but not in the beginning of growing season in all years from 1985 to 2003. The disparity between the simulation and the observation appeared to be related to soil water. Based on our research findings, a water-heat-based phenological model was developed for simulating the beginning of growing season for these two grass species. The simulated results of the new model showed a significant correlation with the observation of beginning date of the growing season, and both mean values of the absolute error were less than 6 days. [ABSTRACT FROM AUTHOR]

A correction to the article "High Capacity and Cycling Stability of Poly(diaminoanthraquinone) as an Organic Cathode for Rechargeable Lithium Batteries" published in a previous issue of "Journal of Polymer Science" is presented.