Arbuscular mycorrhizal fungi(AMF)can improve plant tolerance to several abiotic stresses,including heavy metals,drought or salinity exposure.However,the role of AMF in alleviation of soil cadmium(Cd)-induced toxicity ...Arbuscular mycorrhizal fungi(AMF)can improve plant tolerance to several abiotic stresses,including heavy metals,drought or salinity exposure.However,the role of AMF in alleviation of soil cadmium(Cd)-induced toxicity to plants is still largely unknown.In this study,Cd speciation in soil and subcellular distribution of Cd were used to characterize the roles of application AM fungi in the alleviation of Cd toxicity in alfalfa plants.Our results showed that the addition of Glomus mosseae in Cd contaminated soil(10 mg/Kg)significantly increased soil pH,cation exchange capacity(CEC)and organic matter in rhizosphere soil with Medicago truncatula L.,and then account for significantly decreased contents of exchangeable and carbonate-bounded Cd speciation in rhizosphere soil,indicating alleviation of plant toxicity by reduction of bioavailable fractions of Cd.Although there is no significant difference found in Cd accumulation by roots and shoots respectively between Cd and AM-Cd treatments,more portion of Cd was recorded compartmentalization in cell wall fraction of both root and shoot in treatment of Cd with AM application,indicating alleviation of Cd toxicity to plant cell.Herein,application of AM fungi in Cd treatments performed to inhibit the appearance of Cd toxicity symptoms,including the improvement of leaf electrolyte leakage,root elongation,seedling growth and biomass.This information provides a clearer understanding of detoxification strategy of AM fungi on Cd behavior with development and stabilization of soil structure and subcellular distribution of plant.展开更多
The absolute and relative concentrations for six forms of or fractions of Cd (exchangeable,bound to carbonates, weakly-bounded. exchangeable plus weakly-bounded, bound to Fe-Mn oxides,and bound to organic matter sulfi...The absolute and relative concentrations for six forms of or fractions of Cd (exchangeable,bound to carbonates, weakly-bounded. exchangeable plus weakly-bounded, bound to Fe-Mn oxides,and bound to organic matter sulfides) in eight main soil types in China were measured. The regional differentiation situations of various forms of Cd are identified Analytical results indicate that exchangeable forms of Cd and exchangeable plus weakly-bounded forms of Cd have obvious regional differentiation Characteristics. Based on these differentiation rules and the combination features, and by using traditional synthetic inductive method and the principal component analysis method, we divide the concentration distribution s of the two forms of Cd into three categories.展开更多
Background:Excessive drinkers(ED)and patients with alcoholic liver disease(ALD)are several times more susceptible to bacterial and viral infections and have a decrease in antibody responses to vaccinations.Follicular ...Background:Excessive drinkers(ED)and patients with alcoholic liver disease(ALD)are several times more susceptible to bacterial and viral infections and have a decrease in antibody responses to vaccinations.Follicular helper T(TFH)cells are essential to select B cells in the germinal center and to produce antibodies.TFH cells express both a membrane-associated and a soluble form of CD40 ligand(sCD40L),in which the latter form is released to circulation upon T cell activation.The effect of alcohol on TFH cells has not been studied.Objectives:The goals of this study are to determine the levels of TFH and T helper 1(Th1)cells in ED and those with alcoholic cirrhosis(AC)when compared to healthy controls and to determine the prognostic significance of sCD40L in a cohort of patients with AC.Methods:Controls,ED,and those with AC were enrolled.Baseline demographic,laboratory tests,and peripheral blood mononuclear cells(PBMCs)were isolated and assessed via flow cytometry for TFH cells.In vitro study was performed to determine the ability of PBMCs to secrete interferon(IFN)-ɣupon stimulation.Serum sCD40L was also determined and its prognostic significance was tested in a cohort of AC patients.Results:The levels of circulating TFH(cTFH)cells were significantly lower in peripheral blood of subjects with ED and AC compared to controls(P<0.05).IFN-ɣsecretion from PBMCs upon stimulation was also lower in ED and those with cirrhosis.Serum sCD40L was significantly lower in ED and AC when compared to that in controls(P<0.0005).Its level was an independent predictor of mortality.Conclusions:Patients with AC had significantly lower level of cTFH and sCD40L.The level of sCD40L was an independent predictor of mortality in these patients.展开更多
A pot experiment was carried out by growing 29 different genotypes （Amaranthus spp.） of vegetable amaranth under low- （0.12 mg. kg-1） and middle- （0.40 mg · kg-1） cadmium （Cd） exposure. The result showed ...A pot experiment was carried out by growing 29 different genotypes （Amaranthus spp.） of vegetable amaranth under low- （0.12 mg. kg-1） and middle- （0.40 mg · kg-1） cadmium （Cd） exposure. The result showed that amaranth was vulnerable to cadmium （Cd） contamination in soil. Variations of Cd concentrations in both roots and edible parts among genotypes were significant （P 〈 0.001） in both treatments. Cd concentrations in edible parts of the tested genotypes grown under low- and middle-Cd levels were significantly correlated （p 〈 0.01）, implying that Cd- accumulating property of amaranth is genotype-dependent. Differences in Cd chemical forms between cv. Nanxing- dayemashixian （cv. Nan）, a selected typical pollution-safe cultivar （Cd-PSC）, and cv. Pennongjianyexian （cv. Pen）, a selected typical non-Cd-PSC, under different Cd exposure conditions were compared. It was found that the alternation of Cd in FNaC1 （Cd form extracted by 1 mol.L-1NaC1） may be a key factor in regulating Cd accumulation of different amaranth genotypes and that the protein-binding Cd is considered to be associated with Cd translocation. The results indicated that amaranth is capable of enduring high level of Cd pollution when grown as vegetable crop, and accordingly, consuming vegetable amaranth would bring high health risk. Therefore, adopting Cd-PSC strategy would help reducing the risk of Cd pollution in amaranth. In this study, cv. Nan was identified as a Cd-PSC and recommended to be applied production practice.展开更多
基金This work was financially supported by Grants of Science and Technology Department of Sichuan Province(2019YFS0469,2020YFS0344)Educational Department of Sichuan province(17ZB0438).
文摘Arbuscular mycorrhizal fungi(AMF)can improve plant tolerance to several abiotic stresses,including heavy metals,drought or salinity exposure.However,the role of AMF in alleviation of soil cadmium(Cd)-induced toxicity to plants is still largely unknown.In this study,Cd speciation in soil and subcellular distribution of Cd were used to characterize the roles of application AM fungi in the alleviation of Cd toxicity in alfalfa plants.Our results showed that the addition of Glomus mosseae in Cd contaminated soil(10 mg/Kg)significantly increased soil pH,cation exchange capacity(CEC)and organic matter in rhizosphere soil with Medicago truncatula L.,and then account for significantly decreased contents of exchangeable and carbonate-bounded Cd speciation in rhizosphere soil,indicating alleviation of plant toxicity by reduction of bioavailable fractions of Cd.Although there is no significant difference found in Cd accumulation by roots and shoots respectively between Cd and AM-Cd treatments,more portion of Cd was recorded compartmentalization in cell wall fraction of both root and shoot in treatment of Cd with AM application,indicating alleviation of Cd toxicity to plant cell.Herein,application of AM fungi in Cd treatments performed to inhibit the appearance of Cd toxicity symptoms,including the improvement of leaf electrolyte leakage,root elongation,seedling growth and biomass.This information provides a clearer understanding of detoxification strategy of AM fungi on Cd behavior with development and stabilization of soil structure and subcellular distribution of plant.
文摘The absolute and relative concentrations for six forms of or fractions of Cd (exchangeable,bound to carbonates, weakly-bounded. exchangeable plus weakly-bounded, bound to Fe-Mn oxides,and bound to organic matter sulfides) in eight main soil types in China were measured. The regional differentiation situations of various forms of Cd are identified Analytical results indicate that exchangeable forms of Cd and exchangeable plus weakly-bounded forms of Cd have obvious regional differentiation Characteristics. Based on these differentiation rules and the combination features, and by using traditional synthetic inductive method and the principal component analysis method, we divide the concentration distribution s of the two forms of Cd into three categories.
基金This work was supported by VA Merit Award 1I01BX002634,the NIH R21AA022482,R01DK080440,R01DK104656,R01ES025909,R21CA191507,and P30 DK34989(to L.Wang)VA Merit Award 1I01CX000361,NIH U01AA021840,NIH R01 DK107682,NIH R01 AA025208,US DOD W81XWH-12-1-0497(to S.Liangpunsakul),and NIH R21AA024935-01(to L.Wang and S.Liangpunsakul),and NIH R56 AI112398(to A.L.Dent).
文摘Background:Excessive drinkers(ED)and patients with alcoholic liver disease(ALD)are several times more susceptible to bacterial and viral infections and have a decrease in antibody responses to vaccinations.Follicular helper T(TFH)cells are essential to select B cells in the germinal center and to produce antibodies.TFH cells express both a membrane-associated and a soluble form of CD40 ligand(sCD40L),in which the latter form is released to circulation upon T cell activation.The effect of alcohol on TFH cells has not been studied.Objectives:The goals of this study are to determine the levels of TFH and T helper 1(Th1)cells in ED and those with alcoholic cirrhosis(AC)when compared to healthy controls and to determine the prognostic significance of sCD40L in a cohort of patients with AC.Methods:Controls,ED,and those with AC were enrolled.Baseline demographic,laboratory tests,and peripheral blood mononuclear cells(PBMCs)were isolated and assessed via flow cytometry for TFH cells.In vitro study was performed to determine the ability of PBMCs to secrete interferon(IFN)-ɣupon stimulation.Serum sCD40L was also determined and its prognostic significance was tested in a cohort of AC patients.Results:The levels of circulating TFH(cTFH)cells were significantly lower in peripheral blood of subjects with ED and AC compared to controls(P<0.05).IFN-ɣsecretion from PBMCs upon stimulation was also lower in ED and those with cirrhosis.Serum sCD40L was significantly lower in ED and AC when compared to that in controls(P<0.0005).Its level was an independent predictor of mortality.Conclusions:Patients with AC had significantly lower level of cTFH and sCD40L.The level of sCD40L was an independent predictor of mortality in these patients.
文摘A pot experiment was carried out by growing 29 different genotypes （Amaranthus spp.） of vegetable amaranth under low- （0.12 mg. kg-1） and middle- （0.40 mg · kg-1） cadmium （Cd） exposure. The result showed that amaranth was vulnerable to cadmium （Cd） contamination in soil. Variations of Cd concentrations in both roots and edible parts among genotypes were significant （P 〈 0.001） in both treatments. Cd concentrations in edible parts of the tested genotypes grown under low- and middle-Cd levels were significantly correlated （p 〈 0.01）, implying that Cd- accumulating property of amaranth is genotype-dependent. Differences in Cd chemical forms between cv. Nanxing- dayemashixian （cv. Nan）, a selected typical pollution-safe cultivar （Cd-PSC）, and cv. Pennongjianyexian （cv. Pen）, a selected typical non-Cd-PSC, under different Cd exposure conditions were compared. It was found that the alternation of Cd in FNaC1 （Cd form extracted by 1 mol.L-1NaC1） may be a key factor in regulating Cd accumulation of different amaranth genotypes and that the protein-binding Cd is considered to be associated with Cd translocation. The results indicated that amaranth is capable of enduring high level of Cd pollution when grown as vegetable crop, and accordingly, consuming vegetable amaranth would bring high health risk. Therefore, adopting Cd-PSC strategy would help reducing the risk of Cd pollution in amaranth. In this study, cv. Nan was identified as a Cd-PSC and recommended to be applied production practice.
