The dialysis method has been traditionally used for the conversion of native human plasminogen(Glu-Hpg) to lys-plasminogen(Lys-Hpg). Here is described a solid-phase synthesis method for the preparation of an acyl-plas...The dialysis method has been traditionally used for the conversion of native human plasminogen(Glu-Hpg) to lys-plasminogen(Lys-Hpg). Here is described a solid-phase synthesis method for the preparation of an acyl-plasminogen-streptokinase activator complex(APSAC) from Lys-Hpg, streptokinase(SK) and chemical modification (agent(4-amidinophenyl-4′-aminobenzoate hydrochloride)) with the L-lysine-Sepharose 4B Column as the carrier. The new method significantly increases the product yield and purity over the liquid-phase methods. The APSAC prepared with the new method exhibits a significant thrombolytic effect with a long half-life of about 8.8 h in rabbits.展开更多
The chemical modification of human plasminogen(HPg) was studied with 1-ethyl-3-(3- dimethyl aminopropyl) carbodiimide(EDC), N -acetylimidazole(NAI), 1,2-cyclohexanedione(CHD), chloramine T(Ch-T) and N -bro...The chemical modification of human plasminogen(HPg) was studied with 1-ethyl-3-(3- dimethyl aminopropyl) carbodiimide(EDC), N -acetylimidazole(NAI), 1,2-cyclohexanedione(CHD), chloramine T(Ch-T) and N -bromosuccinimide(NBS) as modifying reagents at its carboxyl group, tyrosine, arginine, methionine and tryptophan residues, respectively. The results indicate that tyrosine and arginine residues are not essential for HPg activity, while carboxyl groups, methionine and tryptophan residues are important for the activity of HPg. The Keech and Farrant′s kinetic analysis reveals that one tryptophan residue, one methionine residue and two carboxyl groups are essential for HPg activity.展开更多
Human gastric cancer MKN-45 cells which are resistant to TGF-β growth inhibition and possess TGF-β type Ⅰ and type Ⅲ receptors, but not type Ⅱ receptors, have been used as a model system to reconstitute these caf...Human gastric cancer MKN-45 cells which are resistant to TGF-β growth inhibition and possess TGF-β type Ⅰ and type Ⅲ receptors, but not type Ⅱ receptors, have been used as a model system to reconstitute these caflcer cells with TGF-β RII cDNA. The results of these experiments indicated that the reexpression of TGF-g RII gene in MKN-45 cells can restore their sensitivity to TGFβ growth inhibition, decrease their growth rate, reduce their cloning efficiency in soft agar and tumorigenicity in nude mice in stable transfectants, in comparison with their control MKN-45 cells. Among different RII transfectants,their difference in the changes of these parameters, as a result of the regain of autocrine negative growth control by TGF-β, is roughly proportional to their level of expression of transfected RII mRNA. From these data, it is concluded that the inactivation of TGF-β RII gene is related to the escape of growth control by TGF-β in MKN-45 cells. The importance of the study of the interplay of TGF-β and its receptor system in the negative growth control of gastric cancer, and possibly also of other cancers, is discussed.展开更多
In present study we studied the effect of all-trans retinoic acid(ATRA) and dimethylsulfoxide (DMSO) on the induction of apoptosis in HL-60 cell line. Based on morphological changes by Hochest 33342 staining and ident...In present study we studied the effect of all-trans retinoic acid(ATRA) and dimethylsulfoxide (DMSO) on the induction of apoptosis in HL-60 cell line. Based on morphological changes by Hochest 33342 staining and identification of internucleosomal DNA cleavage by gel electrophoresis, we observed aberrant nuclear chromatin eondensation and ladder-like pattern of DNA degradation. Using Flow Cytometric method, we found sub-G1 peak in RA-treated HL-60 cells starting 5 to 6 d after the initiation of the treatment. However, such an obvious apoptotic peak was not identified in DMSO-differentiated cells. Combining the research accomplished before, our study approves further that apoptosis could be a common mode of death of terminally differentiated HL-60 cells.展开更多
基金Supported by the Natural Science Foundation of Jilin Province(No. 2 0 0 3- 0 5 - 5 0 - 2 ) and the Creative Foundation of JilinU niversit
文摘The dialysis method has been traditionally used for the conversion of native human plasminogen(Glu-Hpg) to lys-plasminogen(Lys-Hpg). Here is described a solid-phase synthesis method for the preparation of an acyl-plasminogen-streptokinase activator complex(APSAC) from Lys-Hpg, streptokinase(SK) and chemical modification (agent(4-amidinophenyl-4′-aminobenzoate hydrochloride)) with the L-lysine-Sepharose 4B Column as the carrier. The new method significantly increases the product yield and purity over the liquid-phase methods. The APSAC prepared with the new method exhibits a significant thrombolytic effect with a long half-life of about 8.8 h in rabbits.
基金Supported by the Natural Science Foundation of Jilin Province( No.0 30 912 )
文摘The chemical modification of human plasminogen(HPg) was studied with 1-ethyl-3-(3- dimethyl aminopropyl) carbodiimide(EDC), N -acetylimidazole(NAI), 1,2-cyclohexanedione(CHD), chloramine T(Ch-T) and N -bromosuccinimide(NBS) as modifying reagents at its carboxyl group, tyrosine, arginine, methionine and tryptophan residues, respectively. The results indicate that tyrosine and arginine residues are not essential for HPg activity, while carboxyl groups, methionine and tryptophan residues are important for the activity of HPg. The Keech and Farrant′s kinetic analysis reveals that one tryptophan residue, one methionine residue and two carboxyl groups are essential for HPg activity.
文摘Human gastric cancer MKN-45 cells which are resistant to TGF-β growth inhibition and possess TGF-β type Ⅰ and type Ⅲ receptors, but not type Ⅱ receptors, have been used as a model system to reconstitute these caflcer cells with TGF-β RII cDNA. The results of these experiments indicated that the reexpression of TGF-g RII gene in MKN-45 cells can restore their sensitivity to TGFβ growth inhibition, decrease their growth rate, reduce their cloning efficiency in soft agar and tumorigenicity in nude mice in stable transfectants, in comparison with their control MKN-45 cells. Among different RII transfectants,their difference in the changes of these parameters, as a result of the regain of autocrine negative growth control by TGF-β, is roughly proportional to their level of expression of transfected RII mRNA. From these data, it is concluded that the inactivation of TGF-β RII gene is related to the escape of growth control by TGF-β in MKN-45 cells. The importance of the study of the interplay of TGF-β and its receptor system in the negative growth control of gastric cancer, and possibly also of other cancers, is discussed.
文摘In present study we studied the effect of all-trans retinoic acid(ATRA) and dimethylsulfoxide (DMSO) on the induction of apoptosis in HL-60 cell line. Based on morphological changes by Hochest 33342 staining and identification of internucleosomal DNA cleavage by gel electrophoresis, we observed aberrant nuclear chromatin eondensation and ladder-like pattern of DNA degradation. Using Flow Cytometric method, we found sub-G1 peak in RA-treated HL-60 cells starting 5 to 6 d after the initiation of the treatment. However, such an obvious apoptotic peak was not identified in DMSO-differentiated cells. Combining the research accomplished before, our study approves further that apoptosis could be a common mode of death of terminally differentiated HL-60 cells.
