We report the systematic survey of the binding free energies at the interface between a carbohydrate binding module(CBM)of Cel7A and the celluloseⅢ_(1)crystal model using grid docking searches and molecular dynamics ...We report the systematic survey of the binding free energies at the interface between a carbohydrate binding module(CBM)of Cel7A and the celluloseⅢ_(1)crystal model using grid docking searches and molecular dynamics simulations.The two hydrophobic crystal surfaces were involved in the distinct energy minima of the binding free energy.The complex models,each with the CBM at the minimum energy position,stably formed in the solution state.The binding free energies of the celluloseⅢ_(1)complex models,based on both static and dynamics states,were comparable to those of the native cellulose complex models.However,the celluloseⅢ_(1)crystal had a larger binding surface,which is compatible with the observed high enzymatic activity of Cel7A for the celluloseⅢ_(1)substrate.展开更多
An efficient and simple method for the preparation of 5-arylamino-1H-tetrazole and 1-aryl-5-amino-1H-tetrazole derivatives is reported using aluminum(Ⅲ) hydrogensulfate(Al(HSO4)3) as an effective heterogeneous ...An efficient and simple method for the preparation of 5-arylamino-1H-tetrazole and 1-aryl-5-amino-1H-tetrazole derivatives is reported using aluminum(Ⅲ) hydrogensulfate(Al(HSO4)3) as an effective heterogeneous catalyst from secondary arylcyanamides. Generally,when the substitution in arylcyanamide is strongly electron-withdrawing the position of equilibrium would shift toward the isomer of 1-aryl-5-amino-1H-tetrazole(B) and as the electron-donating of substituent increased,the position of equilibrium is shifted toward the isomer of 5-arylamino-1H-tetrazole(A).The present methodology offers several advantages,such as excellent yields,short reaction times,easy work-up and greener conditions.展开更多
Background Repeated attacks of bronchial asthma lead to different degrees of airway remodeling,the mechanism of which is not yet clear. Some evidences indicate that it is related to the excessive expression of some gr...Background Repeated attacks of bronchial asthma lead to different degrees of airway remodeling,the mechanism of which is not yet clear. Some evidences indicate that it is related to the excessive expression of some growth promotion factors. Angiotensin Ⅱ is a polypeptide that may be involved in airway remodeling. To evaluate its role in airway remodeling in asthma,we observed the effects of an angiotensin Ⅱ type 1 receptor antagonist (valsartan) on the expression of collagen Ⅲ,collagen Ⅴ,and transforming growth factor β_1 (TGF-β_1) mRNA and protein in the airway walls of sensitized rats.Methods Forty Wistar rats were randomly divided into 5 groups: control group,sensitized group,and valsartan groups 1,2,and 3. The rats in the sensitized group and in valsartan groups 1,2,and 3 were sensitized and challenged with ovalbumin. Rats in control group were sensitized and challenged with 0.9% NaCl. Rats from valsartan groups 1,2,and 3 were drenched with valsartan (10 μg, 20 μg,or 30 μg,respectively) at the time of the ovalbumin challenges. The expression of collagen Ⅲ,collagen Ⅴ,and TGF-β_1 protein were detected using immunohistochemical method in combination with image analysis methods. The expression of TGF-β_1 mRNA was detected by in situ hybridization. Results The expression in the airways of collagen Ⅲ and collagen Ⅴ was significantly higher in rats from the sensitized group (7.73±0.81, 1.34±0.28) and from valsartan groups 1,2,and 3 (5.73±0.64, 1.13±0.15; 4.96±0.51, 0.98±0.08; 4.43±0.35, 0.93±0.06,respectively) than those in the control group (2.65±0.38, 0.67±0.08,P <0.05). In addition,collagen levels were significantly lower in valsartan groups 1,2,and 3 than those from the sensitized group ( P <0.05). The expression of TGF-β_1 mRNA and protein in the airways was significantly higher in rats from the sensitized group (20.49%±3.46%,29.73%±3.25%) and from valsartan groups 1,2,and 3 (16.47%±1.94%, 19.41%±1.87%; 14.38%±1.58%, 18.29%±1.43%; 12.96%±1.73%, 18.63%±1.11%,respectively) than that from the control group (7.84%±1.61%, 5.63%±1.07%,P <0.05). TGF-β_1 mRNA and protein levels were significantly lower in valsartan groups 1,2,and 3 than that in the sensitized group ( P <0.05). Conclusions Angiotensin Ⅱ receptor antagonist valsartan can suppress synthesis of collagen Ⅲ and collagen Ⅴ by downregulating TGF-β_1 mRNA and protein expression. Valsartan can decrease airway remodeling and could play a role in asthma therapy.展开更多
基金supported by JSPS KAKENHI Grant Number 17K00409。
文摘We report the systematic survey of the binding free energies at the interface between a carbohydrate binding module(CBM)of Cel7A and the celluloseⅢ_(1)crystal model using grid docking searches and molecular dynamics simulations.The two hydrophobic crystal surfaces were involved in the distinct energy minima of the binding free energy.The complex models,each with the CBM at the minimum energy position,stably formed in the solution state.The binding free energies of the celluloseⅢ_(1)complex models,based on both static and dynamics states,were comparable to those of the native cellulose complex models.However,the celluloseⅢ_(1)crystal had a larger binding surface,which is compatible with the observed high enzymatic activity of Cel7A for the celluloseⅢ_(1)substrate.
文摘An efficient and simple method for the preparation of 5-arylamino-1H-tetrazole and 1-aryl-5-amino-1H-tetrazole derivatives is reported using aluminum(Ⅲ) hydrogensulfate(Al(HSO4)3) as an effective heterogeneous catalyst from secondary arylcyanamides. Generally,when the substitution in arylcyanamide is strongly electron-withdrawing the position of equilibrium would shift toward the isomer of 1-aryl-5-amino-1H-tetrazole(B) and as the electron-donating of substituent increased,the position of equilibrium is shifted toward the isomer of 5-arylamino-1H-tetrazole(A).The present methodology offers several advantages,such as excellent yields,short reaction times,easy work-up and greener conditions.
基金ThisworkwassupportedbyagrantfromtheShanxiProvinceFoundationforReturnedOverseasChineseScholars (No 9913 -95 )
文摘Background Repeated attacks of bronchial asthma lead to different degrees of airway remodeling,the mechanism of which is not yet clear. Some evidences indicate that it is related to the excessive expression of some growth promotion factors. Angiotensin Ⅱ is a polypeptide that may be involved in airway remodeling. To evaluate its role in airway remodeling in asthma,we observed the effects of an angiotensin Ⅱ type 1 receptor antagonist (valsartan) on the expression of collagen Ⅲ,collagen Ⅴ,and transforming growth factor β_1 (TGF-β_1) mRNA and protein in the airway walls of sensitized rats.Methods Forty Wistar rats were randomly divided into 5 groups: control group,sensitized group,and valsartan groups 1,2,and 3. The rats in the sensitized group and in valsartan groups 1,2,and 3 were sensitized and challenged with ovalbumin. Rats in control group were sensitized and challenged with 0.9% NaCl. Rats from valsartan groups 1,2,and 3 were drenched with valsartan (10 μg, 20 μg,or 30 μg,respectively) at the time of the ovalbumin challenges. The expression of collagen Ⅲ,collagen Ⅴ,and TGF-β_1 protein were detected using immunohistochemical method in combination with image analysis methods. The expression of TGF-β_1 mRNA was detected by in situ hybridization. Results The expression in the airways of collagen Ⅲ and collagen Ⅴ was significantly higher in rats from the sensitized group (7.73±0.81, 1.34±0.28) and from valsartan groups 1,2,and 3 (5.73±0.64, 1.13±0.15; 4.96±0.51, 0.98±0.08; 4.43±0.35, 0.93±0.06,respectively) than those in the control group (2.65±0.38, 0.67±0.08,P <0.05). In addition,collagen levels were significantly lower in valsartan groups 1,2,and 3 than those from the sensitized group ( P <0.05). The expression of TGF-β_1 mRNA and protein in the airways was significantly higher in rats from the sensitized group (20.49%±3.46%,29.73%±3.25%) and from valsartan groups 1,2,and 3 (16.47%±1.94%, 19.41%±1.87%; 14.38%±1.58%, 18.29%±1.43%; 12.96%±1.73%, 18.63%±1.11%,respectively) than that from the control group (7.84%±1.61%, 5.63%±1.07%,P <0.05). TGF-β_1 mRNA and protein levels were significantly lower in valsartan groups 1,2,and 3 than that in the sensitized group ( P <0.05). Conclusions Angiotensin Ⅱ receptor antagonist valsartan can suppress synthesis of collagen Ⅲ and collagen Ⅴ by downregulating TGF-β_1 mRNA and protein expression. Valsartan can decrease airway remodeling and could play a role in asthma therapy.