Peach fruits [Prumus persica （L.） Batsch, cv. Yuhuasanhao] were used as materials to investigate the changes of reactive oxygen species （ROS） and related enzymes in mitochondria respiration during storage and then...Peach fruits [Prumus persica （L.） Batsch, cv. Yuhuasanhao] were used as materials to investigate the changes of reactive oxygen species （ROS） and related enzymes in mitochondria respiration during storage and then their influence on senescence of harvested Peach fruits was studied. The results showed that low temperature （5℃） strongly inhibited the reduction of firmness and the increase in respiration rate. During storage at ambient temperature （20℃）, ROS had a cumulative process while malondialdehye （MDA） content continued to increase in associated with enhanced membrane lipid peroxidation. Lipoxygenase （LOX） activity was strongly inhibited under the low temperature condition. The activities of succinic dehydrogenase （SDH）, cytochrome C oxidase （CCO）, and Ca^2＋-ATPase declined to a certain extent at ambient temperature, while they showed higher activities at low temperature, which may be related to lower membrane lipid peroxidation at low temperature. Higher Ca^2＋ content at ambient temperature may be responsible for impairment of mitochondrial function, thus, leading to fruit senescence. The results showed that under low temperature condition, the low accumulation of ROS and the low level of membrane lipid peroxidation could maintain the function of mitochondria that would help to delay the senescence of peach fruits. These suggested a close relationship existed between ROS metabolism and mitochondrial respiration. It can be inferred that the low temperature helps to delay senescence of peach fruits via suppression of ROS and related enzymes, maintain better homeostasis of Ca^2＋ in mitochondria and thus better mitochondrial functions.展开更多
The fruits of peach cultivar Yuhua 3 were used as materials to investigate the changes of active oxygen and related enzymes in mitochondria respiratory metabolism during ripening of peach fruit, involving their influe...The fruits of peach cultivar Yuhua 3 were used as materials to investigate the changes of active oxygen and related enzymes in mitochondria respiratory metabolism during ripening of peach fruit, involving their influence on the proceeding of peach fruit senescence. The results showed that the large decrease in firmness occurred between maturity II and IV. The decrease in firmness coincided with an increase in respiratory intensity. Obvious peaks of respiratory intensity lagging to the rapid change of fruit firmness could be shown during peach ripening. Reactive oxygen species （ROS） had a cumulative process and positively correlated with respiratory intensity. During peach ripening, the content of Ca^2＋ increased, the activities of succinic dehydrogenase （SDH）, cytochrome C oxidase （CCO）, H＋-ATPase, and Ca^2＋-ATPase decreased varying in different degree at the later step of ripening. These suggested a close relationship existed between ROS metabolism and mitochondrial respiration, namely, both ROS metabolism and mitochondrial respiration probably played important roles in ripening and senescing of peach fruit.展开更多
The effects of lanthanum on the protective enzymes of rape ( Brassica juncea ) were studied in hydroponics experiment. Results show that when treated with 0.3 mg·kg -1 La, the content of chlorophyll and th...The effects of lanthanum on the protective enzymes of rape ( Brassica juncea ) were studied in hydroponics experiment. Results show that when treated with 0.3 mg·kg -1 La, the content of chlorophyll and the activities of peroxidase(POD), catalase(CAT), superoxide dismutase(SOD) and polyphenoloxidase(PPO) in rape increase, but the content of malondialdehyde(MDA) in rape decreases. However, the treatments do not change the content of soluble protein in rape significantly.展开更多
In this study, the changes in activities of peroxidase （POD）, glutathione S-transferase （GST）, catalase （CAT）, and superoxide distmuase （SOD） in leaves of four wheat cultivars, including resistant cultivars Sh...In this study, the changes in activities of peroxidase （POD）, glutathione S-transferase （GST）, catalase （CAT）, and superoxide distmuase （SOD） in leaves of four wheat cultivars, including resistant cultivars Shannong 0431 and Shanhongmai, a mildsusceptible cultivar Lumai 21, and a susceptible cultivar Wenmai 6, were investigated to explore if these antioxidantrelated enzymes were involved in wheat defense response to Rhizoctonia cerealis attack. Results showed that the activities of these enzymes in different wheat cultivars varied greatly after challenging with R. cerealis. The POD activities in resistant cultivars Shannong 0431 and Shanhongmai increased much quicker after the inoculation and displayed much higher activity than that in susceptible cultivar Wenmai 6. In contrast, POD activity showed a slow accumulation and a delayed peak time. The activities of GST and CAT in Shannong 0431 and Lumai 21 increased obviously within 48 h post inoculation （hpi）, whereas SOD activity decreased dramatically within 24 hpi in Shannong 0431 and 24-48 hpi in Lumai 21. In susceptible cultivar Wenmai 6, the SOD and CAT activities didn’t change obviously, whereas the activity of GST was decreased. The activities of CAT and GST in Shanhongmai did not show significant difference compared with those in Wenmai 6. Results suggested that POD activity may be positively associated with wheat defense to R. cerealis.展开更多
[Objective] This study was carried out to explore the effect of poly-β-hydroxybutyrate（PHB） on the performance of the nonspecific immune system in Fenneropenaeus chinensis. [Method] F. chinensis individuals were as...[Objective] This study was carried out to explore the effect of poly-β-hydroxybutyrate（PHB） on the performance of the nonspecific immune system in Fenneropenaeus chinensis. [Method] F. chinensis individuals were assigned into six groups, and each group was fed with a diet containing 0（Control）, 0.5%（Group E0.5）, 1.0%（Group E1.0）, 2.5%（Group E2.5）, 5.0%（Group E5.0） or 10.0% PHB（Group E10.0）. The mortality rate and relative percent of survival（RPS） of each group were calculated after 6 weeks. Meanwhile, the total antioxidant capacity（T-AOC）, the activity of acid phosphatase（ACP）, peroxidase（POD） and catalase（CAT）, and the content of malondialdehyde（MDA） in hepatopancreas and serum were measured,and their correlation with PHB concentration was analyzed. [Result] The RPS in PHB treated shrimps increased initially and decreased subsequently with increasing PHB concentration. RPS of Group E1.0 was the highest, showing significant difference from that of other groups（ P 〈0.05）.With the increase in PHB concentration, the activity of immunity related enzymes changed in a similar pattern with RPS： increasing at first and decreasing subsequently. In addition, the activity of the enzymes was elevated in the 2nd and 3rd weeks of PHB administration. Among them, T-AOC in serum of groups E1.0 and E2.5, T-AOC in hepatopancreas of Group E1.0, ACP activity in serum of groups E1.0 and E2.5, ACP activity in hepatopancreas of Group E1.0, CAT activity in groups E0.5, E1.0 and E2.5, CAT activity in hepatopancreas of groups E0.5, E1.0 and E10.0, POD activity in both serum and hepatopancreas of groups E0.5, E1.0 and E2.5, SOD activity in both serum and hepatopancreas of Group E1.0, MDA content in serum of Group E1.0 and MDA content in hepatopancreas of groups E0.5 and E1.0 showed significant difference from those of other groups（P〈0.05）. [Conclusion] PHB can improve the immunity of F. chinensis, 1.0% in feed has the best effect, and the total enzyme activity reaches the highest level in the 2nd and 3rd weeks of PHB administration.展开更多
Background Our previous studies demonstrated that divalent organic iron(Fe)proteinate sources with higher complexation or chelation strengths as expressed by the greater quotient of formation(Qf)values displayed highe...Background Our previous studies demonstrated that divalent organic iron(Fe)proteinate sources with higher complexation or chelation strengths as expressed by the greater quotient of formation(Qf)values displayed higher Fe bioavailabilities for broilers.Sodium iron ethylenediaminetetraacetate(NaFeEDTA)is a trivalent organic Fe source with the strongest chelating ligand EDTA.However,the bioavailability of Fe when administered as NaFeEDTA in broilers and other agricultural animals remains untested.Herein,the chemical characteristics of 12 NaFeEDTA products were determined.Of these,one feed grade NaFeEDTA(Qf=2.07×10^(8)),one food grade NaFeEDTA(Qf=3.31×10^(8)),and one Fe proteinate with an extremely strong chelation strength(Fe-Prot ES,Qf value=8,590)were selected.Their bioavailabilities relative to Fe sulfate(FeSO_(4)·7H_(2)O)for broilers fed with a conventional corn-soybean meal diet were evaluated during d 1 to 21 by investigating the effects of the above Fe sources and added Fe levels on the growth performance,hematological indices,Fe contents,activities and gene expressions of Fe-containing enzymes in various tissues of broilers.Results NaFeEDTA sources varied greatly in their chemical characteristics.Plasma Fe concentration(PI),transferrin saturation(TS),liver Fe content,succinate dehydrogenase(SDH)activities in liver,heart,and kidney,catalase(CAT)activity in liver,and SDH mRNA expressions in liver and kidney increased linearly(P<0.05)with increasing levels of Fe supplementation.However,differences among Fe sources were detected(P<0.05)only for PI,liver Fe content,CAT activity in liver,SDH activities in heart and kidney,and SDH mRNA expressions in liver and kidney.Based on slope ratios from multiple linear regressions of the above indices on daily dietary analyzed Fe intake,the average bioavailabilities of Fe-Prot ES,feed grade NaFeEDTA,and food grade NaFeEDTA relative to the inorganic FeSO_(4)·7H_(2)O(100%)for broilers were 139%,155%,and 166%,respectively.Conclusions The bioavailabilities of organic Fe sources relative to FeSO_(4)·7H_(2)O were closely related to their Qf values,and NaFeEDTA sources with higher Qf values showed higher Fe bioavailabilities for broilers fed with a conventional corn-soybean meal diet.展开更多
Soil organic carbon(SOC)fractions and C turnover related enzyme activities are essential for nutrient cycling.This is because they are regarded as important indicators of soil fertility and quality.We measured the eff...Soil organic carbon(SOC)fractions and C turnover related enzyme activities are essential for nutrient cycling.This is because they are regarded as important indicators of soil fertility and quality.We measured the effects of wheat straw incorporation on SOC fractions and C turnover related enzyme activities in a paddy field in subtropical China.Soil samples were collected from 0-10 cm and 10-20 cm depths after rice harvesting.The total SOC concentrations were higher in the high rate of wheat straw incorporation treatment(NPKS2)than in the not fertilized control(CK)(P<0.05).The concentrations of labile C fractions[i.e.,water soluble organic C(WSOC),hot-water soluble organic C(HWSOC),microbial biomass C(MBC),and easily oxidizable C(EOC)],were higher in the moderate NPKS1 and NPKS2 treatments than in CK and the fertilized treatment without straw(NPK)(P<0.05).The geometric means of labile C(GMC)and C pool management index(CPMI)values were highest in NPKS2(P<0.05).The SOC concentrations correlated positively with the labile C fractions(P<0.05).Soil cellulase activity and the geometric mean of enzyme activities(GMea)were higher in NPKS2 than in CK in all soil layers(P<0.05),and the invertase activity was higher in NPKS2 than in CK in the 0-10 cm layer(P<0.05).Stepwise multiple linear regression indicated that the formation of the SOC,WSOC,HWSOC,MBC,and EOC was mostly enhanced by the cellulase and invertase activities(P<0.05).Therefore,the high rate of wheat straw incorporation may be recommended to increase soil C pool levels and soil fertility in subtropical paddy soils.展开更多
Monoclonal antibody (MAb) to rat liver cyto-chrome P-450j isozyme, an activating enzyme specific to nitrosamine metabolism, was used coupled with immunoblotting, densitometer scanning of SDS-PAGE gels and immunohistoc...Monoclonal antibody (MAb) to rat liver cyto-chrome P-450j isozyme, an activating enzyme specific to nitrosamine metabolism, was used coupled with immunoblotting, densitometer scanning of SDS-PAGE gels and immunohistochemical technique. The trace P-450HSj isozyme (Mr. 51.5 Kd) was found in human gastric mucosa. It was similar to P-450j in molecular weight, catalytic and immunochemical properties. The concentrations of P-450HSj in mucosa of lesser curvature were higher than those in greater curvature. This might be one of the important reasons that lesser curvature is the commonest area for gastric carcinoma. But there was possibly less P-450HSj in gastric mucosa with cancer. Im-munohistochemically, P-450HSj was discovered in the cytoplasm of some glandular epithelial cells, especially in the glands with hyperplastic and intestinal metaplastic changes adjacent to carcinoma. It was also found in some normal glands and in tumor cells of high-differentiated adenocarcinoma, but not in those of low-differentiated ones. Following subjects are discussed: (1) the method of detecting trace P-450HSj, (2) the rule of distribution of P-450HSj, and (3) the relationship between the isozyme and the occurrence of gastric cancer caused by nitrosa-mines.展开更多
By pot experiment under artificially simulated water stress conditions, soluble protein content, MDA content and SOD, POD, CAT and APX activities in Malus sieversfi leaves were determined to reveal the response mechan...By pot experiment under artificially simulated water stress conditions, soluble protein content, MDA content and SOD, POD, CAT and APX activities in Malus sieversfi leaves were determined to reveal the response mechanism of M. sieversii to changes of relative soil water content. According to the results, with the decrease of relative soil water content, MDA content in M. sieversii leaves increased by mem- brane lipid peroxidation. Cells resist water stress-induced membrane lipid peroxidation and clear the increased reactive oxygen species by improving soluble protein content and SOD, POD, CAT and APX activities. However, various enzymes were involved in the response to water stress under different moisture conditions. In addition, the results indicated that M. sieversii had a good adaptability to higher relative soil water contents.展开更多
基金funded by the National Natural Science Fundation of China (30840016)the Natural Science Fundation of Jiangsu Province, China (BK 2010310)the Natural Science Fundation for Colleges and Universities in Jiangsu Province, China (10KJB550004)
文摘Peach fruits [Prumus persica （L.） Batsch, cv. Yuhuasanhao] were used as materials to investigate the changes of reactive oxygen species （ROS） and related enzymes in mitochondria respiration during storage and then their influence on senescence of harvested Peach fruits was studied. The results showed that low temperature （5℃） strongly inhibited the reduction of firmness and the increase in respiration rate. During storage at ambient temperature （20℃）, ROS had a cumulative process while malondialdehye （MDA） content continued to increase in associated with enhanced membrane lipid peroxidation. Lipoxygenase （LOX） activity was strongly inhibited under the low temperature condition. The activities of succinic dehydrogenase （SDH）, cytochrome C oxidase （CCO）, and Ca^2＋-ATPase declined to a certain extent at ambient temperature, while they showed higher activities at low temperature, which may be related to lower membrane lipid peroxidation at low temperature. Higher Ca^2＋ content at ambient temperature may be responsible for impairment of mitochondrial function, thus, leading to fruit senescence. The results showed that under low temperature condition, the low accumulation of ROS and the low level of membrane lipid peroxidation could maintain the function of mitochondria that would help to delay the senescence of peach fruits. These suggested a close relationship existed between ROS metabolism and mitochondrial respiration. It can be inferred that the low temperature helps to delay senescence of peach fruits via suppression of ROS and related enzymes, maintain better homeostasis of Ca^2＋ in mitochondria and thus better mitochondrial functions.
基金supported by the National Natural Science Fundation of China (30840016,30570134)the Key Technologies R&D Program of China during the 11th Five-Year Plan period (2006BAD22B01)the Natural Science Fundation of Jiangsu Province,China(BK 2007076)
文摘The fruits of peach cultivar Yuhua 3 were used as materials to investigate the changes of active oxygen and related enzymes in mitochondria respiratory metabolism during ripening of peach fruit, involving their influence on the proceeding of peach fruit senescence. The results showed that the large decrease in firmness occurred between maturity II and IV. The decrease in firmness coincided with an increase in respiratory intensity. Obvious peaks of respiratory intensity lagging to the rapid change of fruit firmness could be shown during peach ripening. Reactive oxygen species （ROS） had a cumulative process and positively correlated with respiratory intensity. During peach ripening, the content of Ca^2＋ increased, the activities of succinic dehydrogenase （SDH）, cytochrome C oxidase （CCO）, H＋-ATPase, and Ca^2＋-ATPase decreased varying in different degree at the later step of ripening. These suggested a close relationship existed between ROS metabolism and mitochondrial respiration, namely, both ROS metabolism and mitochondrial respiration probably played important roles in ripening and senescing of peach fruit.
文摘The effects of lanthanum on the protective enzymes of rape ( Brassica juncea ) were studied in hydroponics experiment. Results show that when treated with 0.3 mg·kg -1 La, the content of chlorophyll and the activities of peroxidase(POD), catalase(CAT), superoxide dismutase(SOD) and polyphenoloxidase(PPO) in rape increase, but the content of malondialdehyde(MDA) in rape decreases. However, the treatments do not change the content of soluble protein in rape significantly.
基金supported by the National High-Tech R&D Program of China (2006AA10A104)the CoreResearch Budget of the Nonprofit Governmental Re-search Institution (the Public Welfare Project of CAAS,China, 2060302-2-09)
文摘In this study, the changes in activities of peroxidase （POD）, glutathione S-transferase （GST）, catalase （CAT）, and superoxide distmuase （SOD） in leaves of four wheat cultivars, including resistant cultivars Shannong 0431 and Shanhongmai, a mildsusceptible cultivar Lumai 21, and a susceptible cultivar Wenmai 6, were investigated to explore if these antioxidantrelated enzymes were involved in wheat defense response to Rhizoctonia cerealis attack. Results showed that the activities of these enzymes in different wheat cultivars varied greatly after challenging with R. cerealis. The POD activities in resistant cultivars Shannong 0431 and Shanhongmai increased much quicker after the inoculation and displayed much higher activity than that in susceptible cultivar Wenmai 6. In contrast, POD activity showed a slow accumulation and a delayed peak time. The activities of GST and CAT in Shannong 0431 and Lumai 21 increased obviously within 48 h post inoculation （hpi）, whereas SOD activity decreased dramatically within 24 hpi in Shannong 0431 and 24-48 hpi in Lumai 21. In susceptible cultivar Wenmai 6, the SOD and CAT activities didn’t change obviously, whereas the activity of GST was decreased. The activities of CAT and GST in Shanhongmai did not show significant difference compared with those in Wenmai 6. Results suggested that POD activity may be positively associated with wheat defense to R. cerealis.
基金Supported by Central Public-interest Scientific Institution Basal Research Fund,Yellow Sea Fisheries Research Institute,CAFS(20603022017001)National Natural Science Foundation of China(41676148)+1 种基金Taishan Scholar Program for Seed IndustryChina Agriculture Research System(CARS-48)
文摘[Objective] This study was carried out to explore the effect of poly-β-hydroxybutyrate（PHB） on the performance of the nonspecific immune system in Fenneropenaeus chinensis. [Method] F. chinensis individuals were assigned into six groups, and each group was fed with a diet containing 0（Control）, 0.5%（Group E0.5）, 1.0%（Group E1.0）, 2.5%（Group E2.5）, 5.0%（Group E5.0） or 10.0% PHB（Group E10.0）. The mortality rate and relative percent of survival（RPS） of each group were calculated after 6 weeks. Meanwhile, the total antioxidant capacity（T-AOC）, the activity of acid phosphatase（ACP）, peroxidase（POD） and catalase（CAT）, and the content of malondialdehyde（MDA） in hepatopancreas and serum were measured,and their correlation with PHB concentration was analyzed. [Result] The RPS in PHB treated shrimps increased initially and decreased subsequently with increasing PHB concentration. RPS of Group E1.0 was the highest, showing significant difference from that of other groups（ P 〈0.05）.With the increase in PHB concentration, the activity of immunity related enzymes changed in a similar pattern with RPS： increasing at first and decreasing subsequently. In addition, the activity of the enzymes was elevated in the 2nd and 3rd weeks of PHB administration. Among them, T-AOC in serum of groups E1.0 and E2.5, T-AOC in hepatopancreas of Group E1.0, ACP activity in serum of groups E1.0 and E2.5, ACP activity in hepatopancreas of Group E1.0, CAT activity in groups E0.5, E1.0 and E2.5, CAT activity in hepatopancreas of groups E0.5, E1.0 and E10.0, POD activity in both serum and hepatopancreas of groups E0.5, E1.0 and E2.5, SOD activity in both serum and hepatopancreas of Group E1.0, MDA content in serum of Group E1.0 and MDA content in hepatopancreas of groups E0.5 and E1.0 showed significant difference from those of other groups（P〈0.05）. [Conclusion] PHB can improve the immunity of F. chinensis, 1.0% in feed has the best effect, and the total enzyme activity reaches the highest level in the 2nd and 3rd weeks of PHB administration.
基金funded by Jiangsu Shuang Chuang Tuan Dui program (JSSCTD202147)Jiangsu Shuang Chuang Ren Cai program (JSSCRC2021541)+1 种基金Young Elite Scientists Sponsorship Program by CAST (2022QNRC001)the Initiation Funds of Yangzhou University for Distinguished Scientists
文摘Background Our previous studies demonstrated that divalent organic iron(Fe)proteinate sources with higher complexation or chelation strengths as expressed by the greater quotient of formation(Qf)values displayed higher Fe bioavailabilities for broilers.Sodium iron ethylenediaminetetraacetate(NaFeEDTA)is a trivalent organic Fe source with the strongest chelating ligand EDTA.However,the bioavailability of Fe when administered as NaFeEDTA in broilers and other agricultural animals remains untested.Herein,the chemical characteristics of 12 NaFeEDTA products were determined.Of these,one feed grade NaFeEDTA(Qf=2.07×10^(8)),one food grade NaFeEDTA(Qf=3.31×10^(8)),and one Fe proteinate with an extremely strong chelation strength(Fe-Prot ES,Qf value=8,590)were selected.Their bioavailabilities relative to Fe sulfate(FeSO_(4)·7H_(2)O)for broilers fed with a conventional corn-soybean meal diet were evaluated during d 1 to 21 by investigating the effects of the above Fe sources and added Fe levels on the growth performance,hematological indices,Fe contents,activities and gene expressions of Fe-containing enzymes in various tissues of broilers.Results NaFeEDTA sources varied greatly in their chemical characteristics.Plasma Fe concentration(PI),transferrin saturation(TS),liver Fe content,succinate dehydrogenase(SDH)activities in liver,heart,and kidney,catalase(CAT)activity in liver,and SDH mRNA expressions in liver and kidney increased linearly(P<0.05)with increasing levels of Fe supplementation.However,differences among Fe sources were detected(P<0.05)only for PI,liver Fe content,CAT activity in liver,SDH activities in heart and kidney,and SDH mRNA expressions in liver and kidney.Based on slope ratios from multiple linear regressions of the above indices on daily dietary analyzed Fe intake,the average bioavailabilities of Fe-Prot ES,feed grade NaFeEDTA,and food grade NaFeEDTA relative to the inorganic FeSO_(4)·7H_(2)O(100%)for broilers were 139%,155%,and 166%,respectively.Conclusions The bioavailabilities of organic Fe sources relative to FeSO_(4)·7H_(2)O were closely related to their Qf values,and NaFeEDTA sources with higher Qf values showed higher Fe bioavailabilities for broilers fed with a conventional corn-soybean meal diet.
基金This work was funded by the Shanghai Agriculture Applied Technology Development Program,China(Grant No.G20190308)the National Key Research and Development Program of China(2016YFD0801106).
文摘Soil organic carbon(SOC)fractions and C turnover related enzyme activities are essential for nutrient cycling.This is because they are regarded as important indicators of soil fertility and quality.We measured the effects of wheat straw incorporation on SOC fractions and C turnover related enzyme activities in a paddy field in subtropical China.Soil samples were collected from 0-10 cm and 10-20 cm depths after rice harvesting.The total SOC concentrations were higher in the high rate of wheat straw incorporation treatment(NPKS2)than in the not fertilized control(CK)(P<0.05).The concentrations of labile C fractions[i.e.,water soluble organic C(WSOC),hot-water soluble organic C(HWSOC),microbial biomass C(MBC),and easily oxidizable C(EOC)],were higher in the moderate NPKS1 and NPKS2 treatments than in CK and the fertilized treatment without straw(NPK)(P<0.05).The geometric means of labile C(GMC)and C pool management index(CPMI)values were highest in NPKS2(P<0.05).The SOC concentrations correlated positively with the labile C fractions(P<0.05).Soil cellulase activity and the geometric mean of enzyme activities(GMea)were higher in NPKS2 than in CK in all soil layers(P<0.05),and the invertase activity was higher in NPKS2 than in CK in the 0-10 cm layer(P<0.05).Stepwise multiple linear regression indicated that the formation of the SOC,WSOC,HWSOC,MBC,and EOC was mostly enhanced by the cellulase and invertase activities(P<0.05).Therefore,the high rate of wheat straw incorporation may be recommended to increase soil C pool levels and soil fertility in subtropical paddy soils.
文摘Monoclonal antibody (MAb) to rat liver cyto-chrome P-450j isozyme, an activating enzyme specific to nitrosamine metabolism, was used coupled with immunoblotting, densitometer scanning of SDS-PAGE gels and immunohistochemical technique. The trace P-450HSj isozyme (Mr. 51.5 Kd) was found in human gastric mucosa. It was similar to P-450j in molecular weight, catalytic and immunochemical properties. The concentrations of P-450HSj in mucosa of lesser curvature were higher than those in greater curvature. This might be one of the important reasons that lesser curvature is the commonest area for gastric carcinoma. But there was possibly less P-450HSj in gastric mucosa with cancer. Im-munohistochemically, P-450HSj was discovered in the cytoplasm of some glandular epithelial cells, especially in the glands with hyperplastic and intestinal metaplastic changes adjacent to carcinoma. It was also found in some normal glands and in tumor cells of high-differentiated adenocarcinoma, but not in those of low-differentiated ones. Following subjects are discussed: (1) the method of detecting trace P-450HSj, (2) the rule of distribution of P-450HSj, and (3) the relationship between the isozyme and the occurrence of gastric cancer caused by nitrosa-mines.
基金Supported by Science and Technology Innovation Project of Ji'nan City "Identification of Stress-resistant Malus sieversii Germplasm Resources and Screening of Stressresistance Functional Genes"(201401125)~~
文摘By pot experiment under artificially simulated water stress conditions, soluble protein content, MDA content and SOD, POD, CAT and APX activities in Malus sieversfi leaves were determined to reveal the response mechanism of M. sieversii to changes of relative soil water content. According to the results, with the decrease of relative soil water content, MDA content in M. sieversii leaves increased by mem- brane lipid peroxidation. Cells resist water stress-induced membrane lipid peroxidation and clear the increased reactive oxygen species by improving soluble protein content and SOD, POD, CAT and APX activities. However, various enzymes were involved in the response to water stress under different moisture conditions. In addition, the results indicated that M. sieversii had a good adaptability to higher relative soil water contents.
