AIM: To investigate the protective effect against two immune liver injury models in mice by 2-amino-2-[2-(4-octylphenyl) ethyl] propane-l,3-diol hydrochloride and its possible mechanisms in Con A-induced liver damage....AIM: To investigate the protective effect against two immune liver injury models in mice by 2-amino-2-[2-(4-octylphenyl) ethyl] propane-l,3-diol hydrochloride and its possible mechanisms in Con A-induced liver damage. METHODS: Liver tissue or hepatocyte injury was monitored biochemically by measuring alanine aminotransferase (sALT) and aspartate aminotransferase (sAST) activity. Hematoxylin & eosin (HE) staining was used for histopathological examination. To evaluate the role of IFN-γ and IL-4 in the liver injury, serum levels of IFN-γ and IL-4 were determined using commercially available ELISA kit at 12 h after Con A challenge. We also determined FTY 720-induced spleen cell apoptosis by flow cytometry analysis or spleen cell proliferation test. RESULTS: Different doses of FTY 720 treatment dramatically reduced circulating markers of hepatocyte injury in two kinds of immunological liver injury models. FTY 720 dramatically reduced the elevated serum IFN-γ and IL-4 levels after Con A injection. Effect of spleen cell supernatants treated with Con A or FTY 720 on hepatocytes showed that ALT activities in cultured hepatocyte supernatants in Con A treatment group increased markedly and FTY 720 could reduce this elevated ALT activities in FTY 720 treatment group. FTY 720 dose-dependently increased the percentage of apoptotic cells in T cells and inhibited splenocyte proliferation induced by Con A. CONCLUSION: Pretreatment with FTY 720 was shown to produce protective effect on the immune liver injury in mice. The possible mechanism of FTY 720 on Con A-induced liver damage is that it could inhibit lymphocyte proliferation and induce lymphocyte apoptosis, resulting in the reduction of IL-4 or IFN-γ release, and subsequently protecting liver from being damaged by Con A.展开更多
A novel method named two-level group contribution (GC-K) method for the estimation of octanol-water partition coefficient (Kow) of chloride hydrocarbon is presented. The equation includes only normal boiling point...A novel method named two-level group contribution (GC-K) method for the estimation of octanol-water partition coefficient (Kow) of chloride hydrocarbon is presented. The equation includes only normal boiling points and molecular weight of compounds. Group contribution parameters of 12 first-level groups and 7 second-level groups for Kow are obtained by correlating experimental data of three types including 57 compounds. By comparing the estimation results of the first-level with that of the two-level groups, it was observed that the latter is better with the addition of the modification of proximity effects. When compared with Marrero's three-level group contribution approach and atom-fragment contribution method (AFC), the accuracy of the average relative error of GC-K by first-level groups is 7.20% and is preferred to other methods.展开更多
Vapor-liquid equilibrium(VLE)data for water+2-propanol+1-butyl-3-methylimidazolium chloride([bmim]Cl)were measured.Six sets of complete T,x,y data are reported,in which the 2-propanol mole fraction on IL-free basis is...Vapor-liquid equilibrium(VLE)data for water+2-propanol+1-butyl-3-methylimidazolium chloride([bmim]Cl)were measured.Six sets of complete T,x,y data are reported,in which the 2-propanol mole fraction on IL-free basis is fixed separately at 0.1,0.2,0.4,0.6,0.8,and approximate 0.98,while the IL mass fraction is varied from 0.1 to 0.8,in an interval of 0.1.The non-random-two-liquid(NRTL)and electrolyte non-random-two-liquid(eNRTL)equations are used to correlate the experimental data with satisfactory results.The ternary VLE behavior is also modeled with the parameters obtained by correlating two data sets,in which the mole fraction of 2-propanol on IL-free basis is approximately 0.1 and 0.98.In this way,the six sets of data are reproduced satisfactorily.With the eNRTL model,the root-mean-square deviation for temperature is 0.82 K and that for vapor-phase mole fraction is 0.0078.The influences of IL on activity coefficients and relative volatility of the volatile components are also graphically illustrated.展开更多
Anovel solid acid catalyst, which was prepared from sodium alginate (SA) and metal chlorides and characterized with XRD and FT-IR spectrometry, was used for the preparation of biodiesel via esterification reaction. Th...Anovel solid acid catalyst, which was prepared from sodium alginate (SA) and metal chlorides and characterized with XRD and FT-IR spectrometry, was used for the preparation of biodiesel via esterification reaction. The study results showed that the aluminum-alginate complex prepared in a cheap and easy way exhibited high catalytic activity, and a 92.6% conversion of methyl oleate was obtained in the presence of 4m% of catalyst dosage upon refluxing for 3h of methanol and acid mixed in a molar ratio of 10:1. It should be noted that the catalyst can be applied to the esterification reaction of fatty acids with various carbon chain length on methanol or different short chain alcohols, indicating that the catalyst is suitable for the preparation of biodiesel from waste oils with a high acid value.展开更多
OBJECTIVE: To assess the phytochemical contents and antioxidant activities of crude extracts from selected Tulbaghia species.METHODS: Standard methods were used for preliminary phytochemical analysis. The total phenol...OBJECTIVE: To assess the phytochemical contents and antioxidant activities of crude extracts from selected Tulbaghia species.METHODS: Standard methods were used for preliminary phytochemical analysis. The total phenolic acid contents of the plant extracts were determined using the Folin-Ciocalteu method, and the total flavonoid contents were determined using the aluminum chloride colorimetric method. 1,1-Diphenyl-2-picrylhydrazyl and 2,2′-Azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) assays were used to evaluate the antioxidant activities.RESULTS: Phytochemical screening showed flavonoids, glycosides, tannins, terpenoids, saponins,and steroids were present in the Tulbaghia species.The total phenolic acid and flavonoid contents varied in the different plant extracts, ranging from4.50 to 11.10 mg of gallic acid equivalents per gram of fresh material and 3.04 to 9.65 mg of quercetin equivalents per gram, respectively. The IC50 values determined for Tulbaghia alliacea and Tulbaghia violacea based on 1,1-diphenyl-2-picrylhydrazyl(0.06 and 0.08 mg/m L, respectively) and 2,2′-Azino-bis(3-ethylbenzthiazoline-6-sulfonic acid)(0.06 and 0.03 mg/m L, respectively) were low and showed they had potential antioxidant activities.CONCLUSION: Our results suggest that individual compounds from Tulbaghia species should be isolated for analysis of their antioxidant activity because some compounds may work best when pure.展开更多
文摘AIM: To investigate the protective effect against two immune liver injury models in mice by 2-amino-2-[2-(4-octylphenyl) ethyl] propane-l,3-diol hydrochloride and its possible mechanisms in Con A-induced liver damage. METHODS: Liver tissue or hepatocyte injury was monitored biochemically by measuring alanine aminotransferase (sALT) and aspartate aminotransferase (sAST) activity. Hematoxylin & eosin (HE) staining was used for histopathological examination. To evaluate the role of IFN-γ and IL-4 in the liver injury, serum levels of IFN-γ and IL-4 were determined using commercially available ELISA kit at 12 h after Con A challenge. We also determined FTY 720-induced spleen cell apoptosis by flow cytometry analysis or spleen cell proliferation test. RESULTS: Different doses of FTY 720 treatment dramatically reduced circulating markers of hepatocyte injury in two kinds of immunological liver injury models. FTY 720 dramatically reduced the elevated serum IFN-γ and IL-4 levels after Con A injection. Effect of spleen cell supernatants treated with Con A or FTY 720 on hepatocytes showed that ALT activities in cultured hepatocyte supernatants in Con A treatment group increased markedly and FTY 720 could reduce this elevated ALT activities in FTY 720 treatment group. FTY 720 dose-dependently increased the percentage of apoptotic cells in T cells and inhibited splenocyte proliferation induced by Con A. CONCLUSION: Pretreatment with FTY 720 was shown to produce protective effect on the immune liver injury in mice. The possible mechanism of FTY 720 on Con A-induced liver damage is that it could inhibit lymphocyte proliferation and induce lymphocyte apoptosis, resulting in the reduction of IL-4 or IFN-γ release, and subsequently protecting liver from being damaged by Con A.
文摘A novel method named two-level group contribution (GC-K) method for the estimation of octanol-water partition coefficient (Kow) of chloride hydrocarbon is presented. The equation includes only normal boiling points and molecular weight of compounds. Group contribution parameters of 12 first-level groups and 7 second-level groups for Kow are obtained by correlating experimental data of three types including 57 compounds. By comparing the estimation results of the first-level with that of the two-level groups, it was observed that the latter is better with the addition of the modification of proximity effects. When compared with Marrero's three-level group contribution approach and atom-fragment contribution method (AFC), the accuracy of the average relative error of GC-K by first-level groups is 7.20% and is preferred to other methods.
基金Supported by the National Natural Science Foundation of China(20776132)the Natural Science Foundation of Zhejiang Province(Y4100699)
文摘Vapor-liquid equilibrium(VLE)data for water+2-propanol+1-butyl-3-methylimidazolium chloride([bmim]Cl)were measured.Six sets of complete T,x,y data are reported,in which the 2-propanol mole fraction on IL-free basis is fixed separately at 0.1,0.2,0.4,0.6,0.8,and approximate 0.98,while the IL mass fraction is varied from 0.1 to 0.8,in an interval of 0.1.The non-random-two-liquid(NRTL)and electrolyte non-random-two-liquid(eNRTL)equations are used to correlate the experimental data with satisfactory results.The ternary VLE behavior is also modeled with the parameters obtained by correlating two data sets,in which the mole fraction of 2-propanol on IL-free basis is approximately 0.1 and 0.98.In this way,the six sets of data are reproduced satisfactorily.With the eNRTL model,the root-mean-square deviation for temperature is 0.82 K and that for vapor-phase mole fraction is 0.0078.The influences of IL on activity coefficients and relative volatility of the volatile components are also graphically illustrated.
基金financially supported by the International Science & Technology Cooperation Program of China(No.2010DFB60840)the Key Science and Technology Project of Guizhou Province(No.20076004)+1 种基金the Social Development S&T Program(No.SZ-[2009]3011)the National Key Technology R&D Program(No.2006BAD07A12)
文摘Anovel solid acid catalyst, which was prepared from sodium alginate (SA) and metal chlorides and characterized with XRD and FT-IR spectrometry, was used for the preparation of biodiesel via esterification reaction. The study results showed that the aluminum-alginate complex prepared in a cheap and easy way exhibited high catalytic activity, and a 92.6% conversion of methyl oleate was obtained in the presence of 4m% of catalyst dosage upon refluxing for 3h of methanol and acid mixed in a molar ratio of 10:1. It should be noted that the catalyst can be applied to the esterification reaction of fatty acids with various carbon chain length on methanol or different short chain alcohols, indicating that the catalyst is suitable for the preparation of biodiesel from waste oils with a high acid value.
基金Supported by Vaal University of Technology,Private Bag X021,Vanderbijlpark 1900,South Africa
文摘OBJECTIVE: To assess the phytochemical contents and antioxidant activities of crude extracts from selected Tulbaghia species.METHODS: Standard methods were used for preliminary phytochemical analysis. The total phenolic acid contents of the plant extracts were determined using the Folin-Ciocalteu method, and the total flavonoid contents were determined using the aluminum chloride colorimetric method. 1,1-Diphenyl-2-picrylhydrazyl and 2,2′-Azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) assays were used to evaluate the antioxidant activities.RESULTS: Phytochemical screening showed flavonoids, glycosides, tannins, terpenoids, saponins,and steroids were present in the Tulbaghia species.The total phenolic acid and flavonoid contents varied in the different plant extracts, ranging from4.50 to 11.10 mg of gallic acid equivalents per gram of fresh material and 3.04 to 9.65 mg of quercetin equivalents per gram, respectively. The IC50 values determined for Tulbaghia alliacea and Tulbaghia violacea based on 1,1-diphenyl-2-picrylhydrazyl(0.06 and 0.08 mg/m L, respectively) and 2,2′-Azino-bis(3-ethylbenzthiazoline-6-sulfonic acid)(0.06 and 0.03 mg/m L, respectively) were low and showed they had potential antioxidant activities.CONCLUSION: Our results suggest that individual compounds from Tulbaghia species should be isolated for analysis of their antioxidant activity because some compounds may work best when pure.