Objective:Osteoporosis is a systemic metabolic disease characterized by decreased bone mass,deterioration of bone microstructure,and increased fracture risk.Its occurrence is closely related to sex,age,and lifestyle f...Objective:Osteoporosis is a systemic metabolic disease characterized by decreased bone mass,deterioration of bone microstructure,and increased fracture risk.Its occurrence is closely related to sex,age,and lifestyle factors.Environmental exposure to heavy metals and metalloids may also influence its development,although existing findings remain inconsistent.The sex differences in the association between mixed metal exposure and osteoporosis are still unclear.This study aims to investigate whether sex differences exist in the associations between cadmium(Cd),lead(Pb),mercury(Hg),selenium(Se),manganese(Mn),and their mixtures and osteoporosis among men aged≥50 years and postmenopausal women,and to analyze the potential moderating effect of dairy product consumption on these associations.Methods:Data from the National Health and Nutrition Examination Survey(NHANES)2013−2014 and 2017−2018 cycles were used.In men and women separately,generalized linear regression models(univariate regression analysis and multivariate logistic regression)were applied to examine the relationships between single-metal exposure and osteoporosis at the femoral neck and vertebrae.A weighted quantile sum(WQS)model was used to construct a weighted index of mixed metal exposure to quantify the joint effects of multiple metals.Bayesian kernel machine regression(BKMR)was used to systematically evaluate the associations between blood Cd,Pb,Hg,Se,Mn,and their mixtures and osteoporosis at different skeletal sites,capturing potential nonlinear relationships and interactions among metals.Participants were further stratified into high dairy consumption(≥7 times/week)and low dairy consumption(<7 times/week)groups to explore the potential moderating effect of dairy consumption on the association between Cd exposure and osteoporosis.Results:Multivariate logistic regression analysis showed that,in the fully adjusted model,Cd was positively associated with femoral neck osteoporosis in men aged≥50 years[odds ratio(OR)=8.563,95%confidence interval(CI)1.888 to 38.845,P<0.05],whereas Se was negatively associated with femoral neck osteoporosis(OR<0.001,95%CI 0 to 0.150,P<0.05).In postmenopausal women,Cd was positively associated with femoral neck osteoporosis risk(OR=2.148,95%CI 1.038 to 4.443,P<0.05),while Se was negatively associated with femoral neck osteoporosis risk(OR=0.027,95%CI 0.001 to 0.986,P<0.05).No significant association was observed between any metal and vertebral osteoporosis(all P>0.05).The WQS model indicated that mixed metal exposure was positively associated with vertebral osteoporosis in men(OR=1.452,95%CI 0.277 to 2.626,P<0.05),whereas no significant association was observed in women.BKMR analysis showed that mixed metal exposure was positively associated with osteoporosis risk at the femoral neck and vertebrae in men,with Cd contributing most to osteoporosis risk,while no association was observed between mixed metal exposure and osteoporosis risk in women.The positive association between mixed blood metal exposure and osteoporosis risk might be partially offset by Se.In stratified analysis,the association between Cd exposure and osteoporosis was stronger in the high dairy consumption group(OR=1.19,95%CI 0.51 to 2.78,P>0.05)than in the low dairy consumption group(OR=3.12,95%CI 1.84 to 5.30,P<0.05),suggesting that frequent dairy consumption may attenuate the positive association between Cd exposure and femoral neck osteoporosis in women.Conclusion:In men aged≥50 years,mixed metal exposure was positively associated with osteoporosis risk at different skeletal sites(femoral neck and vertebra),with Cd contributing most to the risk.In postmenopausal women,no association between mixed metal exposure and osteoporosis risk was observed,indicating clear sex differences.Selenium and dairy consumption may be potential protective factors for osteoporosis in women,whereas such protective effects were not observed in men.展开更多
Selenium distillation slag(SDS)is a high-value-added secondary resource with a high recovery value.This paper aims to investigate the leaching behavior and kinetics of selenium,tellurium,and copper in the SDS acid oxi...Selenium distillation slag(SDS)is a high-value-added secondary resource with a high recovery value.This paper aims to investigate the leaching behavior and kinetics of selenium,tellurium,and copper in the SDS acid oxidation leaching process with H_(2)SO_(4) and H_(2)O_(2).The experimental results showed that under the optimum conditions,the contents of selenium,tellurium,and copper in the SDS were reduced from 22.13 wt%,3.58 wt%,and 6.42 wt%to 3.06 wt%,0.27 wt%,and 0.33 wt%,respectively.Correspondingly,the recovery rates are 87.08%,97.15%and 99.7%.The leaching processes of selenium and tellurium were controlled by diffusion and chemical reactions,and the leaching behavior of copper was controlled by chemical reactions.Below 45℃,the activation energies for selenium,tellurium,and copper were found to be 26.47,62.18 and 19.67 kJ/mol,respectively.In addition,the contents of lead,silver and gold in the leaching residue are increased to 46.8 wt%,8.35 wt%and 0.27 wt%,respectively.These substances can be utilized as raw materials for the recovery of these valuable metals.Importantly,the entire process does not generate toxic or harmful waste,making it a green and environmentally friendly method for resource recovery.展开更多
The trace element selenium(Se)occurs naturally throughout the earth.Se deficiency has been linked to impaired breast health and other diseases in human and animals.Compared to severe Se deficiency,marginal dietary Se ...The trace element selenium(Se)occurs naturally throughout the earth.Se deficiency has been linked to impaired breast health and other diseases in human and animals.Compared to severe Se deficiency,marginal dietary Se deficiency accusers more frequently in low-Se regions.Therefore,to investigate the Se status and inflammatory response of the mammary gland under marginal dietary Se levels,an lipopolysaccharide(LPS)induced mouse mastitis model was established.Mice were fed with moderate Se diet(0.087 mg•kg^(-1) Se),adequate Se diet(0.15 mg•kg^(-1) Se)or excessive Se diet(1.5 mg•kg^(-1) Se)for 60 days.Se status and inflammatory factors were investigated.Results showed that the Se status of mammary gland correlated with dietary Se levels.Marginal Se deficiency exacerbated mammary tissue histopathology;increased the mRNA level of inflammatory genes tumor necrosis factor alpha(TNF-α),interleukin-1β(IL-1β)and cyclooxygenase-2(COX-2);and enhanced the phosphorylation of NF-κB p65 in mammary gland tissues.Supplementation of Se in diet higher than recommended levels reduced the inflammatory reaction of mammary glands in LPS-induced mastitis model and provided a protective effect.展开更多
A process was proposed to convert and separate selenium and arsenic in copper anode slime(CAS) by low-temperature alkali fusion process.Central composite design was employed to optimize the effective parameters,in whi...A process was proposed to convert and separate selenium and arsenic in copper anode slime(CAS) by low-temperature alkali fusion process.Central composite design was employed to optimize the effective parameters,in which Na OH/CAS mass ratio,fusion temperature and fusion time were selected as variables,and the conversion ratio of selenium and arsenic as responses.Second-order polynomial models of high significance and 3D response surface plots were constructed to show the relationship between the responses and the variables.Optimum area of >90% selenium conversion ratio and >90% arsenic conversion ratio was obtained by the overlaid contours at Na OH/CAS mass ratio of 0.65-0.75,fusion temperature of 803-823 K and fusion time of 20-30 min.The models are validated by experiments in the optimum area,and the results demonstrate that these models are reliable and accurate in predicting the fusion process.展开更多
To study the effects of selenium on root oxidizing ability and yield of rice under ferrous stress, a pot culture experiment was conducted, the activity of glutathione peroxidase (GSH-Px) and the concentration of malon...To study the effects of selenium on root oxidizing ability and yield of rice under ferrous stress, a pot culture experiment was conducted, the activity of glutathione peroxidase (GSH-Px) and the concentration of malonaldelyde (MDA) were determined. The root oxidizing ability and yield characters of rice were examined. Results showed that appropriate amount of Se enhanced the activity of glutathione peroxidase and the oxidizing ability of rice roots significantly, reduced the concentration of MDA, increased 1000-grain weight of rice, F = 26.96**, decreased empty and blighted grain rate, increased the rice yield, F = 11.53**, and enhanced the rice resistance under ferrous stress.展开更多
Water culture experiment was conducted to study the effects of selenium(Se) on glutathione peroxidase(GSH-Px) activity,reduced glutathione(GSH) concentration and the accumulation of malonaldehyde(MDA),the product of l...Water culture experiment was conducted to study the effects of selenium(Se) on glutathione peroxidase(GSH-Px) activity,reduced glutathione(GSH) concentration and the accumulation of malonaldehyde(MDA),the product of lipid peroxidation in rice seedling,as well as the effect of se on oxidizing ability of roots under ferrous stress.Results showed that appropriate amount of se significantly increased GSH-Px activity in rice leaves,F=5.5 *,enhanced the amount of GSH and oxidizing ability of roots and reduced the concentration of MDA,F=4.9 *.Compared with Se0+Fe treatment,Se treatments increased the dry matter weight of rice seedling from 10.06% to 10.43%,F=4.09 *.展开更多
Experiments were conducted to study the effects of selenium (Se) on glutathione peroxidase(GSH-Px) activity and the accumulation of malonaldehyde(MDA),the product of lipid peroxidation in soybean seedling, as well as ...Experiments were conducted to study the effects of selenium (Se) on glutathione peroxidase(GSH-Px) activity and the accumulation of malonaldehyde(MDA),the product of lipid peroxidation in soybean seedling, as well as the effect of Se on cell ultra structure of soybean leaf and nascent root under salt stress. Results showed that appropriate amount of Se addition increased GSH-Px activity in soybean leaves from 0. 810 to 1. 421μmol·g-1 fresh weight·min-1 F = 9.12, and reduced the concentration of MDA from 20.17 to 16.16 μmol·g-1 fresh weight, F = 5.44. Under salt stress,no obvious damage on chloplast membrane was observed in Se treated seedlings,and the structures of chloplast and mitochondrion were integrate,whereas in control (no Se addition),the cell membrane was destroyed seriously,chloplast degraded and mitochondrion disappeared. Compared with control,Se addition increased the dry matter weight of seedling by 2.92% to 21.86%, F =5.97.展开更多
The aim of this study was to study the distribution of Selenium （Se） and Mercury （Hg） in feed and drinking water in Heilongjiang Province and the effect on body of beef cattle. The experiment selected four areas o...The aim of this study was to study the distribution of Selenium （Se） and Mercury （Hg） in feed and drinking water in Heilongjiang Province and the effect on body of beef cattle. The experiment selected four areas of Qiqihar, Harbin, Jixi and Hegang Cities in Heilongjiang Province. In each area, a pasture was selected. Five beef cattle from each ranch were collected. At the same time, blood, liver, muscle, kidney, urine and faece of the cattle were collected, as well as drinking water, feed and formula feed from the ranch. The contents of Se and Hg in the collected samples were detected by inductively coupled plasma mass spectrometry. The results showed that the contents of Se in liver, kidney, urine and blood of beef cattle were increased with the increase of Se contents in drinking water, while the contents of Se in muscle tissue and manure were decreased. When the contents of Se in feed increased, the contents of them in muscle, manure and liver of beef cattle were increased frst and then decreased, while the contents of Se in kidney, urine and blood were decreased frst and then increased. When Hg contents in drinking water were increased, the contents of them in beef cattle tissue, blood and manure were increased frst and then decreased, and the contents of Se in urine were increased frst and them decreased. And when Hg contents in feed increased, the contents of Se and Me were also increased. In conclusion, Se and Hg contents in these areas were within the safety standards, meanwhile, the contents of Se and Hg in body tissues of beef cattle were affected to varying degrees by the contents of selenium and mercury in feed.展开更多
A thermodynamics analysis on the leaching process of selenium residue and discussion on the behaviors of aqueous ionic in the leaching process were carried out. Through thermodynamical calculation, the values of AG an...A thermodynamics analysis on the leaching process of selenium residue and discussion on the behaviors of aqueous ionic in the leaching process were carried out. Through thermodynamical calculation, the values of AG and relevant potential expressions were obtained. According to these thermodynamical data, the φ-pH diagrams of Se-H2O system at 298 and 373 K were obtained; Simultaneously, the φ-pH diagrams of SO2-H2O and SO2-Se-H2O systems were drawn at 298 K. With increasing the temperature, the stable regions of HSeO3, SeO2- and SeO2- in the φ-pH diagram of Se-H2O system become gradually large, but the limits of pH in the stable region become gradually small. The stability area of reduction precipitation in the SO2-Se-H2O system was finally determined. The results of oxidization leaching experiments of selenium residue indicate that when the mass ratio of selenium residue to sodium chlorate is 2, the concentration of sulfuric acid is 300 g/L and the residue is agitated for 3 h at leaching temperature of 80 ℃, the leaching rate of selenium could reach 97.76 %. The experimental results conform the calculated results by φ-pH diagram. The selenium reduction precipitation in oxidization-leaching solution was analyzed under the conditions of acidity of 150 g/L, the sodium sulphite concentration of 35 g/L at the reductive temperature of 23 ℃ for 120 min. And this demonstrates the thermodynamics analysis.展开更多
Selenium is one of essential elements for humans,animals and some kinds of plants.The biological function of selenium shows dual characteristics.The range of selenium content is very narrow between toxic and deficient...Selenium is one of essential elements for humans,animals and some kinds of plants.The biological function of selenium shows dual characteristics.The range of selenium content is very narrow between toxic and deficient concentration.Typical Kashin-Beck endemic areas intimately link with selenium deficiency.展开更多
Selenium is a useful element in plant growth and it’s also an necessary ingredient for animal life.The inadequateness or excessiveness of selenium content and different forms of selenium in soil can affect the plant ...Selenium is a useful element in plant growth and it’s also an necessary ingredient for animal life.The inadequateness or excessiveness of selenium content and different forms of selenium in soil can affect the plant growth directly and then bring about further influence to the health of human and animals by food-chain.So it is significant to study the transport and transformation of the selenium in the soil profile.展开更多
In order to interpret pathologic mechanism of free radicals and thyroid hormone metabolism in cattle iodine and selenium deficiency, 20 heads of yellow cattle were selected from NiuJia town, Wu Chang City, Heilongjian...In order to interpret pathologic mechanism of free radicals and thyroid hormone metabolism in cattle iodine and selenium deficiency, 20 heads of yellow cattle were selected from NiuJia town, Wu Chang City, Heilongjiang Province, China, and were randomly devided into 4 groups with 5 for each. ① supplemented with 0.7 mg·kg -1 iodine(potassium iodine), ② supplemented with 0.2 mg·kg -1 selenium (sodium selenite), ③ supplemented with 0.7 mg·kg -1 iodine(potassium Iodine) plus 0.2 mg·kg -1 selenium (sodium selenite) per day for 30 days, respectively. ④control group. The whole blood glutathione peroxidase (GSH-px) and catalase (CAT) activities, free radicals (FR) concentration, erythrocyte superoxide dismutase (SOD) activity and molonaldehyde (MDA) concentration, the serum triiodothyronine (T 3)、thyroxine (T 4) and thyrotropin (TSH) were determined on the day of supplementation day-0 and day-30, respectively. It was showed that average iodine concentration in drinking water and diet were 3.82 μg·L -1 and 0.285mg·kg -1 , respectively, Diet selenium was 0.0498mg·kg -1 , Serum protein bound iodine(PBI) was 7.02 μg·100 mL, Blood selenium was 0.14 mg·L -1 , the schoolchildren′s goiter was 21.8%. It indicated that iodine and selenium were deficient in the investigated area. Whole blood GSH-px and CAT activities and serum T 3 concentration were significantly higher (P< 0.01 ), FR concentration and serum TSH were significantly lower(P<0.01) in the first three groups than that of the control, T 4 content in the first group was higher(P<0.05), T 4 was also higher (P>0.05) in the second group. and lower in the third group. The SOD and MDA in erythrocyte were not changed during the experimental period, The results also showed that GSH-px and CAT activities were increased, and FR decreased oberviously in the third group more than the other two groups, In addition, Thyroid hormone metabolism was more coincided with the physiologic status in the third group. the iodine and the selenium played an important role in the pathologic process of free radical metabolic disorder. selenium not only had the function of antioxidation by derectly scavenging free radicals, but also affected through GSH-px and CAT activities. iodine deficiency results in the Goiter, selenium deficiency aggravated iodine deficiency, Iodine and the selenium were dependent and restrained each other in the course of free radicals and thyroid hormone metabolism with a synergistic state.展开更多
Gas chromatography/inductively coupled plasma mass spectrometry (GC/ICP-MS) coupled with solid phase micro-extraction can provide a simple, extremely selective and sensitive technique for the analysis of volatile sulf...Gas chromatography/inductively coupled plasma mass spectrometry (GC/ICP-MS) coupled with solid phase micro-extraction can provide a simple, extremely selective and sensitive technique for the analysis of volatile sulfur and selenium compounds in the headspace of growing plants. In this work, the technique was used to evaluate the volatilization of selenium in wild-type and genetically-modified Brassica juncea seedlings. By converting toxic inorganic selenium in the soil to less toxic, volatile organic selenium, B. juncea might be useful in bioremediation of selenium contaminated soil.展开更多
基金supported by the Science and Technology Innovation Program of Hunan Province(2025RC3061)the Natural Science Foundation of Hunan Province(2022JJ30828)+2 种基金the Grants from Hunan Provincial Clinical Medicine Research Center for Intelligent Management of Chronic Disease(2023SK4042)the Innovation Foundation For Postgraduate of Hunan Province(CX20240310)the Postgraduate Innovative Project of Central South University(2023XQLH183),China。
文摘Objective:Osteoporosis is a systemic metabolic disease characterized by decreased bone mass,deterioration of bone microstructure,and increased fracture risk.Its occurrence is closely related to sex,age,and lifestyle factors.Environmental exposure to heavy metals and metalloids may also influence its development,although existing findings remain inconsistent.The sex differences in the association between mixed metal exposure and osteoporosis are still unclear.This study aims to investigate whether sex differences exist in the associations between cadmium(Cd),lead(Pb),mercury(Hg),selenium(Se),manganese(Mn),and their mixtures and osteoporosis among men aged≥50 years and postmenopausal women,and to analyze the potential moderating effect of dairy product consumption on these associations.Methods:Data from the National Health and Nutrition Examination Survey(NHANES)2013−2014 and 2017−2018 cycles were used.In men and women separately,generalized linear regression models(univariate regression analysis and multivariate logistic regression)were applied to examine the relationships between single-metal exposure and osteoporosis at the femoral neck and vertebrae.A weighted quantile sum(WQS)model was used to construct a weighted index of mixed metal exposure to quantify the joint effects of multiple metals.Bayesian kernel machine regression(BKMR)was used to systematically evaluate the associations between blood Cd,Pb,Hg,Se,Mn,and their mixtures and osteoporosis at different skeletal sites,capturing potential nonlinear relationships and interactions among metals.Participants were further stratified into high dairy consumption(≥7 times/week)and low dairy consumption(<7 times/week)groups to explore the potential moderating effect of dairy consumption on the association between Cd exposure and osteoporosis.Results:Multivariate logistic regression analysis showed that,in the fully adjusted model,Cd was positively associated with femoral neck osteoporosis in men aged≥50 years[odds ratio(OR)=8.563,95%confidence interval(CI)1.888 to 38.845,P<0.05],whereas Se was negatively associated with femoral neck osteoporosis(OR<0.001,95%CI 0 to 0.150,P<0.05).In postmenopausal women,Cd was positively associated with femoral neck osteoporosis risk(OR=2.148,95%CI 1.038 to 4.443,P<0.05),while Se was negatively associated with femoral neck osteoporosis risk(OR=0.027,95%CI 0.001 to 0.986,P<0.05).No significant association was observed between any metal and vertebral osteoporosis(all P>0.05).The WQS model indicated that mixed metal exposure was positively associated with vertebral osteoporosis in men(OR=1.452,95%CI 0.277 to 2.626,P<0.05),whereas no significant association was observed in women.BKMR analysis showed that mixed metal exposure was positively associated with osteoporosis risk at the femoral neck and vertebrae in men,with Cd contributing most to osteoporosis risk,while no association was observed between mixed metal exposure and osteoporosis risk in women.The positive association between mixed blood metal exposure and osteoporosis risk might be partially offset by Se.In stratified analysis,the association between Cd exposure and osteoporosis was stronger in the high dairy consumption group(OR=1.19,95%CI 0.51 to 2.78,P>0.05)than in the low dairy consumption group(OR=3.12,95%CI 1.84 to 5.30,P<0.05),suggesting that frequent dairy consumption may attenuate the positive association between Cd exposure and femoral neck osteoporosis in women.Conclusion:In men aged≥50 years,mixed metal exposure was positively associated with osteoporosis risk at different skeletal sites(femoral neck and vertebra),with Cd contributing most to the risk.In postmenopausal women,no association between mixed metal exposure and osteoporosis risk was observed,indicating clear sex differences.Selenium and dairy consumption may be potential protective factors for osteoporosis in women,whereas such protective effects were not observed in men.
基金Project(2022YFC2904900) supported by the National Key Research and Development Program of ChinaProject(U1902221) supported by the National Natural Science Foundation of China。
文摘Selenium distillation slag(SDS)is a high-value-added secondary resource with a high recovery value.This paper aims to investigate the leaching behavior and kinetics of selenium,tellurium,and copper in the SDS acid oxidation leaching process with H_(2)SO_(4) and H_(2)O_(2).The experimental results showed that under the optimum conditions,the contents of selenium,tellurium,and copper in the SDS were reduced from 22.13 wt%,3.58 wt%,and 6.42 wt%to 3.06 wt%,0.27 wt%,and 0.33 wt%,respectively.Correspondingly,the recovery rates are 87.08%,97.15%and 99.7%.The leaching processes of selenium and tellurium were controlled by diffusion and chemical reactions,and the leaching behavior of copper was controlled by chemical reactions.Below 45℃,the activation energies for selenium,tellurium,and copper were found to be 26.47,62.18 and 19.67 kJ/mol,respectively.In addition,the contents of lead,silver and gold in the leaching residue are increased to 46.8 wt%,8.35 wt%and 0.27 wt%,respectively.These substances can be utilized as raw materials for the recovery of these valuable metals.Importantly,the entire process does not generate toxic or harmful waste,making it a green and environmentally friendly method for resource recovery.
基金Supported by the Natural Science Foundation of the Heilongjiang Province of China(C2016003)China Postdoctoral Science Foundation(2015M581415)Heilongjiang Postdoctoral Fund(LBH-Z15005)。
文摘The trace element selenium(Se)occurs naturally throughout the earth.Se deficiency has been linked to impaired breast health and other diseases in human and animals.Compared to severe Se deficiency,marginal dietary Se deficiency accusers more frequently in low-Se regions.Therefore,to investigate the Se status and inflammatory response of the mammary gland under marginal dietary Se levels,an lipopolysaccharide(LPS)induced mouse mastitis model was established.Mice were fed with moderate Se diet(0.087 mg•kg^(-1) Se),adequate Se diet(0.15 mg•kg^(-1) Se)or excessive Se diet(1.5 mg•kg^(-1) Se)for 60 days.Se status and inflammatory factors were investigated.Results showed that the Se status of mammary gland correlated with dietary Se levels.Marginal Se deficiency exacerbated mammary tissue histopathology;increased the mRNA level of inflammatory genes tumor necrosis factor alpha(TNF-α),interleukin-1β(IL-1β)and cyclooxygenase-2(COX-2);and enhanced the phosphorylation of NF-κB p65 in mammary gland tissues.Supplementation of Se in diet higher than recommended levels reduced the inflammatory reaction of mammary glands in LPS-induced mastitis model and provided a protective effect.
基金Project(51234009)supported by the National Natural Science Foundation of ChinaProject(2014DFA90520)supported by International Cooperation Program of Ministry of Science of ChinaProject(2013A100003)supported by the Production,Teaching and Research Program of Guangdong Province,China
文摘A process was proposed to convert and separate selenium and arsenic in copper anode slime(CAS) by low-temperature alkali fusion process.Central composite design was employed to optimize the effective parameters,in which Na OH/CAS mass ratio,fusion temperature and fusion time were selected as variables,and the conversion ratio of selenium and arsenic as responses.Second-order polynomial models of high significance and 3D response surface plots were constructed to show the relationship between the responses and the variables.Optimum area of >90% selenium conversion ratio and >90% arsenic conversion ratio was obtained by the overlaid contours at Na OH/CAS mass ratio of 0.65-0.75,fusion temperature of 803-823 K and fusion time of 20-30 min.The models are validated by experiments in the optimum area,and the results demonstrate that these models are reliable and accurate in predicting the fusion process.
文摘To study the effects of selenium on root oxidizing ability and yield of rice under ferrous stress, a pot culture experiment was conducted, the activity of glutathione peroxidase (GSH-Px) and the concentration of malonaldelyde (MDA) were determined. The root oxidizing ability and yield characters of rice were examined. Results showed that appropriate amount of Se enhanced the activity of glutathione peroxidase and the oxidizing ability of rice roots significantly, reduced the concentration of MDA, increased 1000-grain weight of rice, F = 26.96**, decreased empty and blighted grain rate, increased the rice yield, F = 11.53**, and enhanced the rice resistance under ferrous stress.
文摘Water culture experiment was conducted to study the effects of selenium(Se) on glutathione peroxidase(GSH-Px) activity,reduced glutathione(GSH) concentration and the accumulation of malonaldehyde(MDA),the product of lipid peroxidation in rice seedling,as well as the effect of se on oxidizing ability of roots under ferrous stress.Results showed that appropriate amount of se significantly increased GSH-Px activity in rice leaves,F=5.5 *,enhanced the amount of GSH and oxidizing ability of roots and reduced the concentration of MDA,F=4.9 *.Compared with Se0+Fe treatment,Se treatments increased the dry matter weight of rice seedling from 10.06% to 10.43%,F=4.09 *.
文摘Experiments were conducted to study the effects of selenium (Se) on glutathione peroxidase(GSH-Px) activity and the accumulation of malonaldehyde(MDA),the product of lipid peroxidation in soybean seedling, as well as the effect of Se on cell ultra structure of soybean leaf and nascent root under salt stress. Results showed that appropriate amount of Se addition increased GSH-Px activity in soybean leaves from 0. 810 to 1. 421μmol·g-1 fresh weight·min-1 F = 9.12, and reduced the concentration of MDA from 20.17 to 16.16 μmol·g-1 fresh weight, F = 5.44. Under salt stress,no obvious damage on chloplast membrane was observed in Se treated seedlings,and the structures of chloplast and mitochondrion were integrate,whereas in control (no Se addition),the cell membrane was destroyed seriously,chloplast degraded and mitochondrion disappeared. Compared with control,Se addition increased the dry matter weight of seedling by 2.92% to 21.86%, F =5.97.
基金Supported by"Beef Cattle Safety Production Technology Innovation Integration and Demonstration"(2014BAD13B03-1)from the National Science and Technology Support Program"Beef Safety Production Technology Integration and Demonstration"
文摘The aim of this study was to study the distribution of Selenium （Se） and Mercury （Hg） in feed and drinking water in Heilongjiang Province and the effect on body of beef cattle. The experiment selected four areas of Qiqihar, Harbin, Jixi and Hegang Cities in Heilongjiang Province. In each area, a pasture was selected. Five beef cattle from each ranch were collected. At the same time, blood, liver, muscle, kidney, urine and faece of the cattle were collected, as well as drinking water, feed and formula feed from the ranch. The contents of Se and Hg in the collected samples were detected by inductively coupled plasma mass spectrometry. The results showed that the contents of Se in liver, kidney, urine and blood of beef cattle were increased with the increase of Se contents in drinking water, while the contents of Se in muscle tissue and manure were decreased. When the contents of Se in feed increased, the contents of them in muscle, manure and liver of beef cattle were increased frst and then decreased, while the contents of Se in kidney, urine and blood were decreased frst and then increased. When Hg contents in drinking water were increased, the contents of them in beef cattle tissue, blood and manure were increased frst and then decreased, and the contents of Se in urine were increased frst and them decreased. And when Hg contents in feed increased, the contents of Se and Me were also increased. In conclusion, Se and Hg contents in these areas were within the safety standards, meanwhile, the contents of Se and Hg in body tissues of beef cattle were affected to varying degrees by the contents of selenium and mercury in feed.
基金Project(51072233) supported by the National Natural Science Foundation of China
文摘A thermodynamics analysis on the leaching process of selenium residue and discussion on the behaviors of aqueous ionic in the leaching process were carried out. Through thermodynamical calculation, the values of AG and relevant potential expressions were obtained. According to these thermodynamical data, the φ-pH diagrams of Se-H2O system at 298 and 373 K were obtained; Simultaneously, the φ-pH diagrams of SO2-H2O and SO2-Se-H2O systems were drawn at 298 K. With increasing the temperature, the stable regions of HSeO3, SeO2- and SeO2- in the φ-pH diagram of Se-H2O system become gradually large, but the limits of pH in the stable region become gradually small. The stability area of reduction precipitation in the SO2-Se-H2O system was finally determined. The results of oxidization leaching experiments of selenium residue indicate that when the mass ratio of selenium residue to sodium chlorate is 2, the concentration of sulfuric acid is 300 g/L and the residue is agitated for 3 h at leaching temperature of 80 ℃, the leaching rate of selenium could reach 97.76 %. The experimental results conform the calculated results by φ-pH diagram. The selenium reduction precipitation in oxidization-leaching solution was analyzed under the conditions of acidity of 150 g/L, the sodium sulphite concentration of 35 g/L at the reductive temperature of 23 ℃ for 120 min. And this demonstrates the thermodynamics analysis.
文摘Selenium is one of essential elements for humans,animals and some kinds of plants.The biological function of selenium shows dual characteristics.The range of selenium content is very narrow between toxic and deficient concentration.Typical Kashin-Beck endemic areas intimately link with selenium deficiency.
文摘Selenium is a useful element in plant growth and it’s also an necessary ingredient for animal life.The inadequateness or excessiveness of selenium content and different forms of selenium in soil can affect the plant growth directly and then bring about further influence to the health of human and animals by food-chain.So it is significant to study the transport and transformation of the selenium in the soil profile.
文摘In order to interpret pathologic mechanism of free radicals and thyroid hormone metabolism in cattle iodine and selenium deficiency, 20 heads of yellow cattle were selected from NiuJia town, Wu Chang City, Heilongjiang Province, China, and were randomly devided into 4 groups with 5 for each. ① supplemented with 0.7 mg·kg -1 iodine(potassium iodine), ② supplemented with 0.2 mg·kg -1 selenium (sodium selenite), ③ supplemented with 0.7 mg·kg -1 iodine(potassium Iodine) plus 0.2 mg·kg -1 selenium (sodium selenite) per day for 30 days, respectively. ④control group. The whole blood glutathione peroxidase (GSH-px) and catalase (CAT) activities, free radicals (FR) concentration, erythrocyte superoxide dismutase (SOD) activity and molonaldehyde (MDA) concentration, the serum triiodothyronine (T 3)、thyroxine (T 4) and thyrotropin (TSH) were determined on the day of supplementation day-0 and day-30, respectively. It was showed that average iodine concentration in drinking water and diet were 3.82 μg·L -1 and 0.285mg·kg -1 , respectively, Diet selenium was 0.0498mg·kg -1 , Serum protein bound iodine(PBI) was 7.02 μg·100 mL, Blood selenium was 0.14 mg·L -1 , the schoolchildren′s goiter was 21.8%. It indicated that iodine and selenium were deficient in the investigated area. Whole blood GSH-px and CAT activities and serum T 3 concentration were significantly higher (P< 0.01 ), FR concentration and serum TSH were significantly lower(P<0.01) in the first three groups than that of the control, T 4 content in the first group was higher(P<0.05), T 4 was also higher (P>0.05) in the second group. and lower in the third group. The SOD and MDA in erythrocyte were not changed during the experimental period, The results also showed that GSH-px and CAT activities were increased, and FR decreased oberviously in the third group more than the other two groups, In addition, Thyroid hormone metabolism was more coincided with the physiologic status in the third group. the iodine and the selenium played an important role in the pathologic process of free radical metabolic disorder. selenium not only had the function of antioxidation by derectly scavenging free radicals, but also affected through GSH-px and CAT activities. iodine deficiency results in the Goiter, selenium deficiency aggravated iodine deficiency, Iodine and the selenium were dependent and restrained each other in the course of free radicals and thyroid hormone metabolism with a synergistic state.
文摘Gas chromatography/inductively coupled plasma mass spectrometry (GC/ICP-MS) coupled with solid phase micro-extraction can provide a simple, extremely selective and sensitive technique for the analysis of volatile sulfur and selenium compounds in the headspace of growing plants. In this work, the technique was used to evaluate the volatilization of selenium in wild-type and genetically-modified Brassica juncea seedlings. By converting toxic inorganic selenium in the soil to less toxic, volatile organic selenium, B. juncea might be useful in bioremediation of selenium contaminated soil.
