Based on the EDRF(endothelium derived relaxing factor)-like effects for polyarginine Arg-Arg-oH was selected as the lead compound and its derivatives Arg-Arg- OCH_3.Arg Arg-Arg-OH,HO-ArgCOCH_2CH_2COArg-OH,HO-ArgCOCH_2...Based on the EDRF(endothelium derived relaxing factor)-like effects for polyarginine Arg-Arg-oH was selected as the lead compound and its derivatives Arg-Arg- OCH_3.Arg Arg-Arg-OH,HO-ArgCOCH_2CH_2COArg-OH,HO-ArgCOCH_2COArg-OH,were synthesized.These substances showed on bioassay various degrees of vasorelaxant activities. With protection for the C-terminal of Arg-Arg-OH with a methyl ester.the vasorelaxing ac- tivitv was decreased.In contrast.when the N-terminal of Arg-OH was protected with mal- onic acid or butane diacid.the biological activites were lower than those of Arg-Arg-OH due to the lowered metabolic rate.With protection of N-terminal of Arg-Arg-OH with L-Arg residue.Arg-Arg-Arg-OH was obtained,which showed a vasorelaxing activity better than that of Arg-Arg-OH.The bioactivities observed on the Wister's rats for the former com- pound become the experimental basis for prodrug design of EDRF.展开更多
Peptides are known to on act to discourage the growth of insects. In this perspective, authors studied the biological and physiological effects of LeucokininlI on the growth of Red Palm Weevil through adult insect fee...Peptides are known to on act to discourage the growth of insects. In this perspective, authors studied the biological and physiological effects of LeucokininlI on the growth of Red Palm Weevil through adult insect feeding of the sugar cane treated with different concentrations (0.05%, 0. I%, 0.25%, 0.4%) and biological effects on the number of eggs, the percentage of hatching, the length of the generation and the proportion of deformation, Results showed that there is a significant reduction in the number of eggs laid by the insects as the average number of eggs/female 75.7, 63.5, 59.4, 55.1 egg for each of the concentrations, respectively, compared with the average 140.2 egg in the control group, and reduction of percentages of hatching in all treatment as 71.4%, 64.6%, 70% and 71.5% respectively, compared with 79.3% of the control group. The percentage of deformations in egg densities included 44.4%, 15.4%, 22.6%, 27.8% compared to the control group. The results showed that there are a number of large deformations in the resulting larvae for different treatments. The conclusion is drawn that this study using LeucokininlI confirmed inhibition growth and caused an imbalance in the development stages of different insects due to its effect on the hormones that control molting of insects. This conclusion is furthermore apparent in the larval stage, as it appeared that Leucokininll prevents the insect from completing its life cycle. Test results using LeucokininlI are encouraging, and its future potential use in reducing Red Palm Weevil deserves broader studies. If the spread of currently known that this LeucokininlI is without prejudice to the work of the hormonal system.展开更多
The object of this study is to investigate the effect of VIP on pulmonary artery of chronically hypoxic rats. It was shown that chronic hypoxia depressed significantly pulmonary artery relaxation induced by VIP as com...The object of this study is to investigate the effect of VIP on pulmonary artery of chronically hypoxic rats. It was shown that chronic hypoxia depressed significantly pulmonary artery relaxation induced by VIP as compared with those of control (P<0. 001). The vascular relaxation of both groups was correlated with concentration of VIP. In addition, the relaxant effect of VIP on pulmonary arteries in rats was endothelium─independent, and was not prevented by indomethacin or nordihydroguaiaretic acid, but was abolished completely by methylene blue. These results suggest that the lower relaxation of pulmonary artery in rats might not be due to the endothelial injury caused by chronic hypoxia, and chronic hypoxia may inhibit directly the soluble guanylate cyclase in vascular smooth muscle cells invloved in synthesis of cGMP and thus reduced the sensitivity and reactivity of pulmonary artery to VIP.展开更多
This study investigated the inductive effect ofAlexandrium tamarense, a toxic dinoflagellate producing paralytic shell- fish poison, on oxidative stress and apoptosis in hepatopancreas of Chinese shrimp, Fenneropenaeu...This study investigated the inductive effect ofAlexandrium tamarense, a toxic dinoflagellate producing paralytic shell- fish poison, on oxidative stress and apoptosis in hepatopancreas of Chinese shrimp, Fenneropenaeus chinensis. The individuals of E chinensis were exposed to 200 and 1000 cells mL-1 of A. tamarense with their superoxide dismutase (SOD), glutathione S-transferase (GST) activities, malonyldialdehyde (MDA) concentration, and caspase gene (FcCasp) expression in hepatopancreas determined at 12, 24, 48, 72 and 96 h. In addition, apoptosis in hepatopancreas of E chinensis at 96 h after exposure was determined through terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay. The hepatopancreatic SOD and GST activities of F. chinensis exposed to 1000 cells mL-1 ofA. tamarense showed a bell-shaped response to exposure time. The hepatopancreatic MDA concentration ofF. chinensis exposed to 1000 cellsmL-1 ofA. tamarense increased gradually from 48 to 96h, and such a trend corresponded to the decrease of GST activity. The hepatopancreatic FcCasp transcript abundance of F. chinensis exposed to 1000 cells mL-1 ofA. tamarense was positively and linearly correlated to MDA concentration. Results of TUNEL assay showed that exposure to 1000 cells mL-1 of A. tamarense induced apoptosis in the hepatopancreas of E chinensis. Our study revealed that A. tamarense exposure influenced the antioxidative status ofF. chinensis and caused lipid peroxidation and apoptosis in the hepatopancreas of shrimp.展开更多
To estimate the antioxidant activities of Peanut polypeptides (PPs) by using a chemiluminescence (CL) method in vitro. The scavenging ability of PPs on superoxide anion, hydroxide radical, and hydrogen peroxide wa...To estimate the antioxidant activities of Peanut polypeptides (PPs) by using a chemiluminescence (CL) method in vitro. The scavenging ability of PPs on superoxide anion, hydroxide radical, and hydrogen peroxide was determined by the Pyrogallol-Luminol system, the CuSO4-Phen-Vc-H2O2 system, and the luminol-H2O2 system, respectively. DNA damage preventing the effect of PPs was determined by the CuSO4-Phen-Vc-H2O2-DNA CL system. The results shows that PPs had good effect on the scavenging ability of superoxide anion (IC50=9.68±0.12 mg/ml). PPs could scavenge hydroxide radical effectively (the IC50 value was 46.06±0.08 μg/ml). PPs had a good scavenging ability on hydrogen peroxide, which had a relatively low IC50 value (0.17±0.07 mg/ml). PPs (the IC50 value was0.72±0.11 mg/ml) were powerful on the DNA damage preventing effect. PPs possesses a good scavenging potency on ROS in different systems, but different results exist in different systems.展开更多
The 4N1K peptide,which is derived from the C-terminal domain of thrombospondin-1(TSP-1),is usually used as a functional mimic peptide for TSP-1.Knowledge about the interaction force of 4N1K/CD47 is important in explai...The 4N1K peptide,which is derived from the C-terminal domain of thrombospondin-1(TSP-1),is usually used as a functional mimic peptide for TSP-1.Knowledge about the interaction force of 4N1K/CD47 is important in explaining how TSP-1 affects the biological effect of CD47.Here we used a single-molecule force spectroscopy(SMFS)technique to explore the interaction of 4N1K/CD47 on both normal and oxidative human red blood cells(h RBCs)at single-molecule level.There was no interaction force between 4N1K and CD47 on normal h RBCs;however,we did find 4N1K-bound CD47 on oxidative h RBCs.We also detected interaction forces for 4N1K/CD47ex(extracellular domain of human CD47),and 4N1K/oxidative CD47ex.The interaction forces of 4N1K/CD47ex were almost consistent with those of 4N1K/oxidative CD47ex at the same loading rate.These results suggest that the conformational change of CD47 is critical for 4N1K-CD47 interaction on oxidative h RBCs.展开更多
基金This project was supported by the National Natural Science Foundation of China
文摘Based on the EDRF(endothelium derived relaxing factor)-like effects for polyarginine Arg-Arg-oH was selected as the lead compound and its derivatives Arg-Arg- OCH_3.Arg Arg-Arg-OH,HO-ArgCOCH_2CH_2COArg-OH,HO-ArgCOCH_2COArg-OH,were synthesized.These substances showed on bioassay various degrees of vasorelaxant activities. With protection for the C-terminal of Arg-Arg-OH with a methyl ester.the vasorelaxing ac- tivitv was decreased.In contrast.when the N-terminal of Arg-OH was protected with mal- onic acid or butane diacid.the biological activites were lower than those of Arg-Arg-OH due to the lowered metabolic rate.With protection of N-terminal of Arg-Arg-OH with L-Arg residue.Arg-Arg-Arg-OH was obtained,which showed a vasorelaxing activity better than that of Arg-Arg-OH.The bioactivities observed on the Wister's rats for the former com- pound become the experimental basis for prodrug design of EDRF.
文摘Peptides are known to on act to discourage the growth of insects. In this perspective, authors studied the biological and physiological effects of LeucokininlI on the growth of Red Palm Weevil through adult insect feeding of the sugar cane treated with different concentrations (0.05%, 0. I%, 0.25%, 0.4%) and biological effects on the number of eggs, the percentage of hatching, the length of the generation and the proportion of deformation, Results showed that there is a significant reduction in the number of eggs laid by the insects as the average number of eggs/female 75.7, 63.5, 59.4, 55.1 egg for each of the concentrations, respectively, compared with the average 140.2 egg in the control group, and reduction of percentages of hatching in all treatment as 71.4%, 64.6%, 70% and 71.5% respectively, compared with 79.3% of the control group. The percentage of deformations in egg densities included 44.4%, 15.4%, 22.6%, 27.8% compared to the control group. The results showed that there are a number of large deformations in the resulting larvae for different treatments. The conclusion is drawn that this study using LeucokininlI confirmed inhibition growth and caused an imbalance in the development stages of different insects due to its effect on the hormones that control molting of insects. This conclusion is furthermore apparent in the larval stage, as it appeared that Leucokininll prevents the insect from completing its life cycle. Test results using LeucokininlI are encouraging, and its future potential use in reducing Red Palm Weevil deserves broader studies. If the spread of currently known that this LeucokininlI is without prejudice to the work of the hormonal system.
文摘The object of this study is to investigate the effect of VIP on pulmonary artery of chronically hypoxic rats. It was shown that chronic hypoxia depressed significantly pulmonary artery relaxation induced by VIP as compared with those of control (P<0. 001). The vascular relaxation of both groups was correlated with concentration of VIP. In addition, the relaxant effect of VIP on pulmonary arteries in rats was endothelium─independent, and was not prevented by indomethacin or nordihydroguaiaretic acid, but was abolished completely by methylene blue. These results suggest that the lower relaxation of pulmonary artery in rats might not be due to the endothelial injury caused by chronic hypoxia, and chronic hypoxia may inhibit directly the soluble guanylate cyclase in vascular smooth muscle cells invloved in synthesis of cGMP and thus reduced the sensitivity and reactivity of pulmonary artery to VIP.
基金supported by Earmarked Fund for Modern Agro-industry Technology Research System of China (Grant No. CARS-47)Special Fund for Agroscientific Research in the Public Interest of China (Grant No. 201103034)the National ‘863’ Project of China (Grant No. 2012AA10A409)
文摘This study investigated the inductive effect ofAlexandrium tamarense, a toxic dinoflagellate producing paralytic shell- fish poison, on oxidative stress and apoptosis in hepatopancreas of Chinese shrimp, Fenneropenaeus chinensis. The individuals of E chinensis were exposed to 200 and 1000 cells mL-1 of A. tamarense with their superoxide dismutase (SOD), glutathione S-transferase (GST) activities, malonyldialdehyde (MDA) concentration, and caspase gene (FcCasp) expression in hepatopancreas determined at 12, 24, 48, 72 and 96 h. In addition, apoptosis in hepatopancreas of E chinensis at 96 h after exposure was determined through terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay. The hepatopancreatic SOD and GST activities of F. chinensis exposed to 1000 cells mL-1 ofA. tamarense showed a bell-shaped response to exposure time. The hepatopancreatic MDA concentration ofF. chinensis exposed to 1000 cellsmL-1 ofA. tamarense increased gradually from 48 to 96h, and such a trend corresponded to the decrease of GST activity. The hepatopancreatic FcCasp transcript abundance of F. chinensis exposed to 1000 cells mL-1 ofA. tamarense was positively and linearly correlated to MDA concentration. Results of TUNEL assay showed that exposure to 1000 cells mL-1 of A. tamarense induced apoptosis in the hepatopancreas of E chinensis. Our study revealed that A. tamarense exposure influenced the antioxidative status ofF. chinensis and caused lipid peroxidation and apoptosis in the hepatopancreas of shrimp.
文摘To estimate the antioxidant activities of Peanut polypeptides (PPs) by using a chemiluminescence (CL) method in vitro. The scavenging ability of PPs on superoxide anion, hydroxide radical, and hydrogen peroxide was determined by the Pyrogallol-Luminol system, the CuSO4-Phen-Vc-H2O2 system, and the luminol-H2O2 system, respectively. DNA damage preventing the effect of PPs was determined by the CuSO4-Phen-Vc-H2O2-DNA CL system. The results shows that PPs had good effect on the scavenging ability of superoxide anion (IC50=9.68±0.12 mg/ml). PPs could scavenge hydroxide radical effectively (the IC50 value was 46.06±0.08 μg/ml). PPs had a good scavenging ability on hydrogen peroxide, which had a relatively low IC50 value (0.17±0.07 mg/ml). PPs (the IC50 value was0.72±0.11 mg/ml) were powerful on the DNA damage preventing effect. PPs possesses a good scavenging potency on ROS in different systems, but different results exist in different systems.
基金financially supported by the National Basic Research Program of China(2011CB933600,2013CB966900)the National Natural Science Foundation of China(21373200,81273334)Program for Changjiang Scholars and Innovative Research Team in University(PCSIRT,IRT1133)
文摘The 4N1K peptide,which is derived from the C-terminal domain of thrombospondin-1(TSP-1),is usually used as a functional mimic peptide for TSP-1.Knowledge about the interaction force of 4N1K/CD47 is important in explaining how TSP-1 affects the biological effect of CD47.Here we used a single-molecule force spectroscopy(SMFS)technique to explore the interaction of 4N1K/CD47 on both normal and oxidative human red blood cells(h RBCs)at single-molecule level.There was no interaction force between 4N1K and CD47 on normal h RBCs;however,we did find 4N1K-bound CD47 on oxidative h RBCs.We also detected interaction forces for 4N1K/CD47ex(extracellular domain of human CD47),and 4N1K/oxidative CD47ex.The interaction forces of 4N1K/CD47ex were almost consistent with those of 4N1K/oxidative CD47ex at the same loading rate.These results suggest that the conformational change of CD47 is critical for 4N1K-CD47 interaction on oxidative h RBCs.