Three Bi-doped vanadyl pyrophosphate catalysts were prepared via dihydrate route （VPD method）, which consisted of different preparation methods including mechanosynthesis, mechanochemical treatment, and the conventi...Three Bi-doped vanadyl pyrophosphate catalysts were prepared via dihydrate route （VPD method）, which consisted of different preparation methods including mechanosynthesis, mechanochemical treatment, and the conventional reflux method. The catalysts produced by the above three methods were characterized by x-ray diffraction （XRD）, scanning electron microscopy （SEM）, and temperature programmed reduction （TPR）. Catalytic evaluation for the partial oxidation of n-butane to maleic anhydride （MA） was also carried out. The XRD patterns of all the Bi-doped catalysts showed the main peaks of pyrophosphate phase. Lower intensity peaks were observed for the mechanochemically treated Bi-doped catalyst （VPDBiMill） with two additional small peaks corresponding to the presence of a small amount of V5＋ phase. The TPR profiles showed that the highest amount of active oxygen species, i.e, V4＋–O- pair, responsible for n-butane activation, was removed from VPDBiMill. Furthermore, from the catalytic test results, the graph of selectivity to MA as a function of the conversion of n-butane demonstrated that VPDBiMill was the most selective catalyst. This suggests that the mechanochemical treatment of vanadium phosphate catalyst （VPDBiMill） is a potential method to improve the catalytic properties for the partial oxidation of n-butane to maleic anhydride.展开更多
Background and Objective: Interleukin-1 (IL-1) binds to 2 distinct and separate receptors, types I and II (IL-1RI and IL-1RII, respectively). The binding of IL-1 to IL-1RI induces cellular signaling and biological eff...Background and Objective: Interleukin-1 (IL-1) binds to 2 distinct and separate receptors, types I and II (IL-1RI and IL-1RII, respectively). The binding of IL-1 to IL-1RI induces cellular signaling and biological effects, whereas binding to IL-1RII does not induce cellular signaling and indirectly inhibits IL-1 biological activities such as that of the decoy receptor. Recently, Suzukiet al.reported that soluble IL-1RII (sIL-1RII) was detected in gingival crevicular fluid from a periodontitis patient. However, it remains unclear which cells produce sIL-1RII detected in periodontal tissues. We examined the localization of IL-1RII producing cells in gingival tissues as well as related production control mechanisms. Material and Methods: IL-1RII mRNA expression in gingival epithelial cells (GE1) was performed by real-time PCR analysis, while the amount of sIL-1RII production in supernatant from GE1 cells was examined by dot-blot analysis. Involvement of the phosphorylation of STAT6 in the signaling pathway was determined by western blot analysis. Statistical analysis was performed with Student’st-test. Results: Culturing with IL-4 and IL-13 significantly increased IL-1RII mRNA to levels 10.5-and 8.89-fold, respectively, above that of the control (p< 0.01), while addition of interferon-γ (IFN-γ) significantly suppressed IL-1RII mRNA by 0.22-fold as compared to the control (p< 0.05). Soluble IL-1RII in the supernatant of cultured GE1 cells was increased by IL-4 and IL-13, and decreased by IFN-γ, while western blotting determines the suppression of IL-1RII production by IFN-γ. Without the addition of IL-4 or IL-13 with or without IFN-γ, P-Tyr-STAT6 was not detected. Conclusion: IL-1RII mRNA expression and sIL-1RII production were increased by IL-4 and IL-13, and decreased by IFN-γ. Finally, IL-4 signaling was regulated by IFN-γ through phosphorylation of STAT6 and IL-13 signaling blockage by IFN-γ downstream of STAT6 translocation.展开更多
文摘Three Bi-doped vanadyl pyrophosphate catalysts were prepared via dihydrate route （VPD method）, which consisted of different preparation methods including mechanosynthesis, mechanochemical treatment, and the conventional reflux method. The catalysts produced by the above three methods were characterized by x-ray diffraction （XRD）, scanning electron microscopy （SEM）, and temperature programmed reduction （TPR）. Catalytic evaluation for the partial oxidation of n-butane to maleic anhydride （MA） was also carried out. The XRD patterns of all the Bi-doped catalysts showed the main peaks of pyrophosphate phase. Lower intensity peaks were observed for the mechanochemically treated Bi-doped catalyst （VPDBiMill） with two additional small peaks corresponding to the presence of a small amount of V5＋ phase. The TPR profiles showed that the highest amount of active oxygen species, i.e, V4＋–O- pair, responsible for n-butane activation, was removed from VPDBiMill. Furthermore, from the catalytic test results, the graph of selectivity to MA as a function of the conversion of n-butane demonstrated that VPDBiMill was the most selective catalyst. This suggests that the mechanochemical treatment of vanadium phosphate catalyst （VPDBiMill） is a potential method to improve the catalytic properties for the partial oxidation of n-butane to maleic anhydride.
文摘Background and Objective: Interleukin-1 (IL-1) binds to 2 distinct and separate receptors, types I and II (IL-1RI and IL-1RII, respectively). The binding of IL-1 to IL-1RI induces cellular signaling and biological effects, whereas binding to IL-1RII does not induce cellular signaling and indirectly inhibits IL-1 biological activities such as that of the decoy receptor. Recently, Suzukiet al.reported that soluble IL-1RII (sIL-1RII) was detected in gingival crevicular fluid from a periodontitis patient. However, it remains unclear which cells produce sIL-1RII detected in periodontal tissues. We examined the localization of IL-1RII producing cells in gingival tissues as well as related production control mechanisms. Material and Methods: IL-1RII mRNA expression in gingival epithelial cells (GE1) was performed by real-time PCR analysis, while the amount of sIL-1RII production in supernatant from GE1 cells was examined by dot-blot analysis. Involvement of the phosphorylation of STAT6 in the signaling pathway was determined by western blot analysis. Statistical analysis was performed with Student’st-test. Results: Culturing with IL-4 and IL-13 significantly increased IL-1RII mRNA to levels 10.5-and 8.89-fold, respectively, above that of the control (p< 0.01), while addition of interferon-γ (IFN-γ) significantly suppressed IL-1RII mRNA by 0.22-fold as compared to the control (p< 0.05). Soluble IL-1RII in the supernatant of cultured GE1 cells was increased by IL-4 and IL-13, and decreased by IFN-γ, while western blotting determines the suppression of IL-1RII production by IFN-γ. Without the addition of IL-4 or IL-13 with or without IFN-γ, P-Tyr-STAT6 was not detected. Conclusion: IL-1RII mRNA expression and sIL-1RII production were increased by IL-4 and IL-13, and decreased by IFN-γ. Finally, IL-4 signaling was regulated by IFN-γ through phosphorylation of STAT6 and IL-13 signaling blockage by IFN-γ downstream of STAT6 translocation.
