Objective To explore the feasibility using aluminum tripolyphosphate as the synthesis of aspirin model instead of sulfuric acid catalyst. Methods The thermodynamic functions of the reaction system of salicylic acid and acetic anhydride were calculated according to the Benson group contribution method and Joback group contribution method.The enthalpy change,entropy and Gibbs free energy along with the change of temperature as well as the influence of the molar rate of reactants on the equilibrium conversation rate were also studied.Results In the temperature range of 298.15 K to 358.15 K,the reaction enthalpy was less than zero,and was exothermic reaction,and increase of temperature was not conducive to the reaction.The improvement of mole ratio of salicylic acid and acetic anhydride was helpful to improve the equilibrium conversation rate.The theoretical conversion rate could reach 99.58% when the mole ratio of salicylic acid and acetic anhydride was 3.Conclusion From the viewpoint of thermodynamics, the reaction is practical and feasible.

Objective:To clarify the effect of miR-200c on the proliferation of retroperitoneal fibroblast, and analyze its molecular mechanism, which provide theoretical basis for the inhibition of retroperitoneal fibrosis. Methods: 36 cases of retroperitoneal tissues were collected, and the primary fibroblasts were cultured. The cells stimulated by 5 ng/ml transforming growth factor-β1 (TGF-β1) were used as TGF-β1 group;the cells were transfected with pcDNA3.1-miR-200c first, and then stimulated by 5 ng/ml TGF-β1 were used as miR-200c group;the cells transfected only by pcDNA 3.1 were used as pcDNA 3.1 group;the normal cultured cells were used as control group. The MTT assay, cell scratch and Transwell chamber were used to detect the proliferation and migration of fibroblast, respectively. The ELISA experiment was used to detect the content of Akt protein in the lysis liquid of each group. Results: The OD value of fibroblast proliferation in miR-200c group was obviously lower than that of TGF-β1 group (P<0.01);compared with TGF-β1 group, the cell migration rate was decreased significantly in miR-200c group (P<0.01);the content of Akt protein in miR-200c was obviously lower than that of TGF-β1 group (P<0.01). Conclusion: miR-200c inhibits the effect of TGF-β1 on the proliferation and migration of fibroblast by down-regulating Akt signaling pathway, which has important significance in inhibiting peritoneal fibrosis.