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Proton exchang e membranes e xhibiting a well-org anized structure were successfully prepared by a novel self-assembling technique using surface- -charged latex nanoparticles as building blocks. The nanoparticles were synthe- sized in water by free-radical copolymerization. Free-standing membranes were obtained by casting the poly mer e mulsions followed by a cross-linking reac- tion. The acquired membrane exhibited a hig h proton condu ctivity of 0.04 S cm -1 with an ion exchange c apacity ( IEC) as low as 0.48 mmol g -1 . The e n- hanced proton conductivity is thought to be derived from the formation of a co- continuous ionic network for i on channels by the clo sely packed surface-char- ged latex nanoparticles, facilitating proton transportation in the membranes.

We reported proton-conducting membranes with novel microstructure based on partially phosphorylated poly(vinyl alcohol) (P-PVA) and polyethylene glycol (PEG) grafted silica (PEG-SiO2) particles. The PEG-SiO2 particles were synthesized through acid catalyzed hydrolysis and condensation reactions. The membranes were characterized for their mechanical, structural, morphological, and electrical properties by employing tensile test, Fourier transform infrared (FTIR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), impedance analyzer, respectively. In these membranes, P-PVA acts as the proton source and PEG act as the proton solvent. The PEG-riched phases in the hybrid membrane form continuous ionic conducting pathways and subsequently give high ionic conductivity. The results suggest that the obtained membrane shows good thermal stability, excellent mechanical property and high ionic conductivity, and the low-cost hybrid membrane can be a promising candidate for intermediate temperature fuel cell systems.

Background Chronic kidney disease poses a serious health problem worldwide with increasing prevalence and lack of effective treatment. This study aimed to investigate the mechanism of icariin in alleviating chronic renal failure induced by 5/6 nephrectomy in rats. Methods The chronic renal failure model was established by a two-phased 5/6 nephrectomy procedure. The model rats were given daily doses of water or icariin for 8 weeks. The kidney morphology was checked by HE staining. The levels of blood urea nitrogen, serum creatinine, and serum uric acid were measured by colometric methods. The expression of specified genes was analyzed by quantitative real-time PCR and immunohistochemical staining. The number of renal stem/progenitor cells was analyzed by CD133 and CD24 immunohistochemical staining. Results Icariin protected against CDK-caused damages to kidney histology and improved renal function, significantly reduced levels of BUN, creatinine, and uric acid. Icariin inhibited the expression level of TGF-β1 whereas upregulated HGF, BMP-7, WT-1, and Pax2 expression. Moreover, ccariin significantly increased the expression of CD24, CD133, Osr1, and Nanog in remnant kidney and the numbers of CD133+/CD24+ renal stem/progenitor cells. Conclusions These data demonstrated that icariin effectively alleviated 5/6 nephrectomy induced chronic renal failure through increasing renal stem/progenitor cells.

There has been an increasing interest in recent years in catalytic cracking of mixed C4 alkene to produce ethylene and propylene over zeolite catalysts. Among numerous catalysts which are used in such a process, the zeolite ZSM-23 showed distinctive potential. In this report, pure and well-crystallized ZSM-23 (MTT) catalyst was synthesized under static hydrothermal conditions using pyrrolidine as template. The product obtained was characterized by powder X-ray diffraction (XRD), ICP atom emission, scanning electron microscopy (SEM), thermal analysis (TGA-DTA) and FTIR of adsorbed pyridine. The ZSM-23 was used as catalyst in mixed C4 alkene cracking and showed very high catalytic activity and yields of ethylene and propylene. The effects of reaction temperature, WHSV crystallite size, pore size and Si/Al ratio on the catalytic activity were also studied in detail.

Herein, we report the effect of parecoxib on the structure and function of human serum albumin (HSA) by using fluorescence, circular dichroism (CD), Fourier transforms infrared (FTIR), three-dimensional (3D) fluorescence spectroscopy, and molecular docking techniques. The Stern-Volmer quenching constants K(SV) and the corresponding thermodynamic parameters ΔH, ΔG, and ΔS have been estimated by the fluorescence quenching method. The results indicated that parecoxib binds spontaneously with HSA through van der Waals forces and hydrogen bonds with binding constant of 3.45 × 10(4) M(-1) at 298 K. It can be seen from far-UV CD spectra that the α-helical network of HSA is disrupted and its content decreases from 60.5% to 49.6% at drug:protein = 10:1. Protein tertiary structural alterations induced by parecoxib were also confirmed by FTIR and 3D fluorescence spectroscopy. The molecular docking study indicated that parecoxib is embedded into the hydrophobic pocket of HSA.