Chitosans reacted with selenious acid to prepare chitosan hydrogen selenites,which were found to be growth-inhibitory against sarcoma 180 solid tumor.The results indicated that the activity also depended on the molecu...Chitosans reacted with selenious acid to prepare chitosan hydrogen selenites,which were found to be growth-inhibitory against sarcoma 180 solid tumor.The results indicated that the activity also depended on the molecular weight of chitosan supports.展开更多
Three novel vanadium selenites with the formulae [（VO2）（1,10-phenanthtoline）（SeO3H）]2 1, [（VO2）（2,2′-bipyridine）]2（SeO3） 2 and [（VO）（H2O）（SeO3）2]2（HaEDD） 3 （EDD = N1,N1′-（ethane-1,2-diyl）dieth...Three novel vanadium selenites with the formulae [（VO2）（1,10-phenanthtoline）（SeO3H）]2 1, [（VO2）（2,2′-bipyridine）]2（SeO3） 2 and [（VO）（H2O）（SeO3）2]2（HaEDD） 3 （EDD = N1,N1′-（ethane-1,2-diyl）diethane-1,2-diamine） were hydrothermally synthesized, and characterized with elemental analysis, FT-IR spectrum, Raman spectrum, TG-DTA analysis, EPR spectra, and single-crystal X-ray diffraction analysis. Compound I belongs to the triclinic system, space group P1^- with a = 7.7527（5）, b = 9.5345（10）, c = 9.8192（8） A^°, α = 92.712（3）, β = 105.540（3）, γ = 108.154（4）°, V = 657.66（1） A^°^3, Mr = 782.22, Z = 1, F（000） = 384,μ（MoKa） = 3.544 mm^-1, R = 0.0432 and wR = 0.1142; Compound 2 is of orthorhombic system, space group F212121 with a = 7.6574（15）, b = 14.916（3）, c = 19.085（4） A, V = 2179.8（8） Aa, Mr = 605.21, Z = 4, F（000） = 1200, μ（MoKa） = 2.579 mm^-1, R = 0.0338 and wR = 0.0658; Compound 3 belongs to the triclinic system, space group P1^- with a = 9.247（2）, b = 9.659（2）, c = 7.2651（19） A^°, α = 98.171（7）, β = 103.709（5）, γ = 114.712（13）°, V = 550.9（2） A^°^3, Mr = 828.03, Z = 1, F（000） = 400, μ（MoKa） = 7.537 mm^-1, R = 0.0641 and wR = 0.2118. Compound 1 is constructed from alternating corner-shared [VO4N2] octahedra and SeO3H units, forming a dimeric vanadium unit. These assemblies are further linked into an infinite chain via hydrogen bonds along the a axis. In the structure of 2, two distinct V centers form centrosymmetric [V2O6N4] clusters through edge-sharing, and the SeO3 unit serves as a capping unit to fix the oxovanadate cluster. In the structure of 3, each [VO6] octahedron shares four oxygen atoms with adjacent Se atoms, while every SeO3 unit shares two oxygen atoms with neighboring V atoms. This connectivity of alternating VO6 and SeO3 units results in a joint-like chain. Based on the TGA analysis, these three compounds are thermally stable under 200℃ .展开更多
Exploring new material systems and enhancing the birefringence of compounds is a highly valuable endeavor.In this study,we introduce a novel method to enhance the birefringence of inorganic compounds by inducing struc...Exploring new material systems and enhancing the birefringence of compounds is a highly valuable endeavor.In this study,we introduce a novel method to enhance the birefringence of inorganic compounds by inducing structural alignment through linear groups and fluoride ions.We report on two new compounds:HgGa_(2)(SeO_(3))_(4) and Hg_(2)Ga(Se_(O)_(3))_(2)F.HgGa_(2)(SeO_(3))_(4) crystallizes in a non-centrosymmetric(NCS)space group,exhibiting a second harmonic generation(SHG)efficiency of approximately 60% that of commercial KH2PO4(KDP),with a birefringence of 0.032@546 nm.Hg_(2)Ga(Se_(O)_(3))_(2)F,on the other hand,crystallizes in a centrosymmetric space(CS)group and represents the first reported HgI-based selenite birefringent material.Due to the influence of the linear group Hg_(2)O_(2),its birefringence is significantly enhanced to 0.111@546 nm,which is 3.5 times that of HgGa_(2)(SeO_(3))_(4).Moreover,both compounds demonstrate high stability and a broad optical transparency window.These findings indicate that Hg_(2)Ga(Se_(O)_(3))_(2)F is a promising candidate for birefringent material in the mid-infrared(MIR)range.Our research provides an innovative strategy for improving the birefringence of compounds.展开更多
[Objectives]To explore the effect of selenium(Se)on inhibiting embryo abortion and enhancing seedling cultivation quality of Red sandalwood(Pterocarpus santalinus).[Methods]Based on prior cultivation practices and exp...[Objectives]To explore the effect of selenium(Se)on inhibiting embryo abortion and enhancing seedling cultivation quality of Red sandalwood(Pterocarpus santalinus).[Methods]Based on prior cultivation practices and experimental research,three categories comprising 13 forest soil nutrient management schemes were designed to investigate the synergistic effects of Se,NPK compound fertilizers,and enzyme-microbe fermented organic fertilizers(EFOF)on embryo abortion,winged pod development,and seedling quality of Red sandalwood.[Results]Increasing the Se content in the soil,particularly in the form of selenite/Se(IV),within one month following the harvest of Red sandalwood pods and within two months prior to flower withering,significantly reduced embryo abortion percentage(EAP),and consequently improved seed quality and yield per plant.The effect of Se application was markedly greater than that of the single application of nitrogen(N),phosphorus(P),potassium(K),boron(B)fertilizers,or organic fertilizers.Furthermore,when Se was applied in combination with NPK compound fertilizers and EFOF,these beneficial effects were significantly enhanced.When Se(IV)was applied individually,the EAP decreased by 62.4%,reaching 24.8% at 8 weeks after flower withering(compared to 65.9%in the unmanaged control,UMC).Following winged pod maturation,the percentage of empty winged pods(PEWP)declined by 65.2% to 16.8%(UMC:48.2%),the average individual winged pod weight(IWPW)increased by 69.1%to 0.690 g per fruit(UMC:0.408 g),and the winged pod yield(WPY)rose by 214.8% to 4.03 kg(UMC:1.28 kg).Additionally,the blasted seed percentage(BSP)was reduced by 51.2% to 29.9%(UMC:61.3%),and the 100-seed weight(HSW)increased by 96.0%to 8.37 g(UMC:4.27 g).Following sowing in the nursery,the seedling emergence rate(SER)increased by 6.57-fold,reaching 59.8%(UMC:7.9%).Additionally,the whole plant biomass of 6-month-old seedlings increased by 52.9%,attaining 1.56 g(UMC:1.02 g).The combined application of EFOF+NPK+Se(IV)significantly reduced the EAP,PEWP,and BSP by 56.5%,46.0%,and 56.3%,respectively,compared to the single application of Se(IV).Furthermore,these percentages decreased by 79.7%,78.9%,and 71.8%,respectively,relative to the single application of NPK compound fertilizers,and by 79.0%,74.5%,and 72.1%,respectively,compared to the single application of EFOF.Additionally,the SER increased by 34.6%,141.0%,and 287.0%,respectively,when compared to the single application of Se(IV),NPK compound fertilizers,and EFOF.[Conclusions]Enhancing the nutrient status of forest soils,particularly the concentration of Se(IV),constitutes a critical technical approach to improving the resistance of Red sandalwood to low-temperature stress during its flowering and fruiting stages,thereby preventing embryo abortion.展开更多
Selenium(Se)is a nutrient that is considered beneficial for plants,because its improvement in growth,yield and quality helps plants to mitigate stress.The objective of this research was to evaluate the application of ...Selenium(Se)is a nutrient that is considered beneficial for plants,because its improvement in growth,yield and quality helps plants to mitigate stress.The objective of this research was to evaluate the application of sodium selenite(Na2SeO3),nanoparticles(SeNPs)and microparticles(SeMPs)of Se in cucumber seedlings,via two experiments:one with seed priming and the other with foliar application of Sematerials.The doses used were:0,0.1,0.5,1.0,1.5 and 3.0 mg⋅L^(−1),for each form of Se and for each form of application.Treatment 0 consisted of the application of distilled water,which was used as a control.The results indicated that the SeMPs treatment at 3.0 mg⋅L^(−1)for seed priming had the greatest effect on stem diameter and leaf area.Foliar application of SeMPs at 1.5 mg⋅L^(−1)was the most effective at increasing the leaf area.In terms of fresh and dry biomass(aerial,root and total)for seed priming,all the treatments were superior to the control,and SeMPs at 1.5 and 3.0 mg⋅L^(−1)caused the greatest effects.With foliar application,fresh root biomass improved to a greater extent with the SeMPs treatment at 3.0 mg⋅L^(−1),and dry biomass(aerial,root and total)increased with the SeMPs at 1.0 and 3.0 mg⋅L^(−1).With respect to the photosynthetic pigments,proteins,phenols and minerals,the Se treatments,both for seed priming and foliar application,caused increases and decreases;however,reduced glutathione(GSH)increased with treatments in both forms of application.The Se concentration in the seedlings increased as the dose of Se material increased,and greater accumulation was achieved with foliar application of SeNPs and SeMPs.The results indicate that the use of Se materials is recommended,mainly the use of SeMPs,which improved the variables studied.This opens new opportunities for further studies with SeMPs,as little information is available on their application in agricultural crops.展开更多
Microbial selenite(Se(Ⅳ)) reduction to elemental selenium nanoparticles(SeNPs) and chromate(Cr(Ⅵ)) remediation constitute effective detoxification processes. The strain Bacillus wiedmannii ES2-45 can efficiently red...Microbial selenite(Se(Ⅳ)) reduction to elemental selenium nanoparticles(SeNPs) and chromate(Cr(Ⅵ)) remediation constitute effective detoxification processes. The strain Bacillus wiedmannii ES2-45 can efficiently reduce 5 mmol/L Se(Ⅳ) into SeNPs over 14 h and 1 mmol/L Cr(Ⅵ) within 36 h. Proteomic analysis and qRT-PCR revealed that reductases, including dithiol oxidoreductase(DsbA), Fe-S biosynthesis domain-containing protein(Fes),and aldose-6-phosphate reductase(Aldo), and bacillithiol(BSH) were involved in Se(Ⅳ) reduction. Heterologous expression further confirmed the Se(Ⅳ)-reducing function of three genes and enhanced the Se(Ⅳ) and Cr(Ⅵ) resistance ability. Moreover, the difference between Se(Ⅳ) treatments and controls both intra-and extra-cellular BSH concentration per biomass indicated that BSH contributes to Se(Ⅳ) reduction. Selenium-fortified rice was obtained by foliar spray of SeNPs synthesized by the strain ES2-45. To the best of our knowledge, DsbA and Aldo reductase were firstly verified for the role in Se(Ⅳ) reduction and Cr(Ⅵ)resistance. Importantly, it is a promising strategy that B. wiedmannii ES2-45 is served as an efficient bacterium for SeNP synthesis, selenium biofortification and heavy metal bioremediation.展开更多
Traditional studies on transforming selenate and selenite are often limited by static measurements and low spatial resolution.They do not fully consider the impact of moisture content.This paper uses the DGT(diffusive...Traditional studies on transforming selenate and selenite are often limited by static measurements and low spatial resolution.They do not fully consider the impact of moisture content.This paper uses the DGT(diffusive gradients in thin films)technique to deeply explore how moisture changes affect the transformation of selenate and selenite in the environment(changes in properties over time).First,representative soil samples(loess)are prepared,and their moisture content is adjusted.Fixed concentrations of selenate and selenite are added,and then the DGT device simulates their migration in the natural environment.The experiment covers drought,moisture,and high moisture environments,and the experiment is repeated under each condition to ensure the accuracy of the data.The sample quality is verified and further analyzed by ion chromatography(IC)and atomic absorption spectroscopy(AAS).This article uses DGT technology to study the influence of moisture content on the migration and transformation of selenate and selenite in soil.Results indicate that increased moisture content leads to higher concentrations,diffusion rates,and DGT capture efficiency of both selenium species,highlighting the importance of moisture in their environmental behavior.When the moisture content increased from 25%to 65%,the coefficient of variation of selenate and selenite increased.The DGT technique proved effective in capturing spatial heterogeneity and providing high-precision measurements,offering robust data to advance research on selenium behavior in soils.展开更多
Two japonica rice （Oryza sativa L.） cultivars, Xiushui 48 and S. Andrea, differing in their ability to accumulate Se in the grain （as high as a three-fold difference）, were compared for selenium （Se） accumulatio...Two japonica rice （Oryza sativa L.） cultivars, Xiushui 48 and S. Andrea, differing in their ability to accumulate Se in the grain （as high as a three-fold difference）, were compared for selenium （Se） accumulation in their shoots when their growth media was supplied with different forms of Se. Results indicated that when treated with 0.25μmol L^-1 Na2SeO3, Xiushui 48 accumulation of Se in the shoots was significantly more rapid （P〈0.05） than S. Andrea, probably because of greater Se uptake and transport in Xiushui 48. Xiushui 48 rice seedlings had a higher shoot-Se accumulation rate and absorbed selenocysteine （Se-Cys） more rapidly than S. Andrea seedlings. However, when treated with Se as 0.25μmol L^-1 selenomethionine （Se-Met）, the S. Andrea seedlings＇ accumulation rate was significantly greater （P〈0.05） than that of Xiushui 48. Possibly, the high Se accumulation rate of Xiushui 48 seedling shoots compared to S. Andrea shoots was the result of a higher capacity of Xiushui 48 to transform selenite to organic Se compounds and a higher selenite uptake rate.展开更多
Hydroxyl release of red soil and latosol surfaces was quantitatively measuredusing a self-made constant pH automated titration instrument, to study the changes of hydroxylrelease with different added selenite amounts ...Hydroxyl release of red soil and latosol surfaces was quantitatively measuredusing a self-made constant pH automated titration instrument, to study the changes of hydroxylrelease with different added selenite amounts and pH levels, and to study the effects ofelectrolytes on hydroxyl release. Hydroxyl release increased with the selenite concentration, with arapid increase at a low selenite concentration while slowing down at a high concentration. The pHwhere maximum of hydroxyl release appeared was not constant, shifting to a lower valus withincreasing selenite concentration. Hydroxyl release decreased with increasing electrolyteconcentration, and the decrease was very rapid at a low electrolyte concentration but slow at a highelectrolyte concentration. For NaClO_4, NaCl and Na_2SO_4, hydroxyl release was in the order ofNaClO_4 > NaCl >> Na_2SO_4, and the difference was very significant. But for NaCl, KCl and CaCl_2,the order of hydroxyl release was NaCl > KCl > CaCl_2, and the difference was smaller. The amount ofhydroxyl release from Xuwen latosol was greater than that from Jinxian red soil. Hydroxyl releaseexisted in a wider range of pH with Xuwen latosol than with Jinxian red soil, due to theirdifference in soil properties. However, both soils had similar curves of hydroxyl release,indicating the common characteristics of variable charge soils.展开更多
Microbes play important roles in the transport and transformation of selenium(Se) in the environment, thereby influencing plant resistance to Se and Se accumulation in plant. The objectives are to characterize the bac...Microbes play important roles in the transport and transformation of selenium(Se) in the environment, thereby influencing plant resistance to Se and Se accumulation in plant. The objectives are to characterize the bacteria with high Se tolerance and reduction capacity and explore the significance of microbial origins on their Se tolerance, reduction rate and efficiency. Two bacterial strains were isolated from a naturally occurred Se-rich soil at tea orchard in southern Anhui Province, China. The reduction kinetics of selenite was investigated and the reducing product was characterized using scanning electron microscopy and transmission electron microscopy-energy dispersive spectroscopy. The bacteria were identified as Lysinibacillus xylanilyticus and Lysinibacillus macrolides,respectively, using morphological, physiological and molecular methods. The results showed that the minimal inhibitory concentrations(MICs) of selenite for L. xylanilyticus and L. macrolides were 120 and 220 mmol/L, respectively, while MICs of selenate for L.xylanilyticus and L. macrolides were 800 and 700 mmol/L, respectively. Both strains aerobically reduced selenite with an initial concentration of 1.0 mmol/L to elemental Se nanoparticles(SeNPs) completely within 36 hr. Biogenic SeNPs were observed both inside and outside the cells suggesting either an intra-or extracellular reduction process. Our study implied that the microbes from Se-rich environments were more tolerant to Se and generally quicker and more efficient than those from Se-free habitats in the reduction of Se oxyanions. The bacterial strains with high Se reduction capacity and the biological synthesized Se NPs would have potential applications in agriculture, food, environment and medicine.展开更多
AIM: To study liver cell apoptosis caused by the toxicity of selenium and observe the alteration of choline compounds using in vitro 9.4T high resolution magnetic resonance spectroscopy. METHODS: Twenty male Wistar ra...AIM: To study liver cell apoptosis caused by the toxicity of selenium and observe the alteration of choline compounds using in vitro 9.4T high resolution magnetic resonance spectroscopy. METHODS: Twenty male Wistar rats were randomly divided into two groups. The rats in the treatment group were intraperitoneally injected with sodium selenite and the control group with distilled water. All rats were sacrifi ced and the livers were dissected. 1H-MRS data were collected using in vitro 9.4T high resolution magnetic resonance spectrometer. Spectra were processed using XWINNMR and MestRe-c 4.3. HE and TUNEL staining was employed to detect and confi rm the change of liver cells. RESULTS: Good 1H-MR spectra of perchloric acid extract from liver tissue of rats were obtained. The conventional metabolites were detected and assigned. Concentrations of different ingredient choline compounds in treatment group vs control group were as follows: total choline compounds,5.08 ± 0.97 mmol/L vs 3.81 ± 1.16 mmol/L (P = 0.05); and free choline,1.07 ± 0.23 mmol/L vs 0.65 ± 0.20 mmol/L (P = 0.00). However,there was no statistical signif icance between the two groups. The hepatic sinus and cellular structure of hepatic cells in treatmentgroup were abnormal. Apoptosis of hepatic cells was confi rmed by TUNEL assay. CONCLUSION: High dose selenium compounds can cause the rat liver lesion and induce cell apoptosis in vivo. High resolution 1H-MRS in vitro can detect diversified metabolism. The changing trend for different ingredient of choline compounds is not completely the same at early period of apoptosis.展开更多
Ferroptosis is a recently discovered form of iron-dependent cell death,which occurs during the pathological process of various central nervous system diseases or injuries,including secondary spinal cord injury.Seleniu...Ferroptosis is a recently discovered form of iron-dependent cell death,which occurs during the pathological process of various central nervous system diseases or injuries,including secondary spinal cord injury.Selenium has been shown to promote neurological function recovery after cerebral hemorrhage by inhibiting ferroptosis.However,whether selenium can promote neurological function recovery after spinal cord injury as well as the underlying mechanism remain poorly understood.In this study,we injected sodium selenite(3μL,2.5μM)into the injury site of a rat model of T10 vertebral contusion injury 10 minutes after spinal cord injury modeling.We found that sodium selenite treatment greatly decreased iron concentration and levels of the lipid peroxidation products malondialdehyde and 4-hydroxynonenal.Furthermore,sodium selenite increased the protein and mRNA expression of specificity protein 1 and glutathione peroxidase 4,promoted the survival of neurons and oligodendrocytes,inhibited the proliferation of astrocytes,and promoted the recovery of locomotive function of rats with spinal cord injury.These findings suggest that sodium selenite can improve the locomotive function of rats with spinal cord injury possibly through the inhibition of ferroptosis via the specificity protein 1/glutathione peroxidase 4 pathway.展开更多
Voltage-dependent anion channel （VDAC）I is the main channel of the mitochondrial outer membrane （MOM） and it has been proposed to be part of the permeability transition pore （PTP）, a putative multiprotein comple...Voltage-dependent anion channel （VDAC）I is the main channel of the mitochondrial outer membrane （MOM） and it has been proposed to be part of the permeability transition pore （PTP）, a putative multiprotein complex candidate agent of the mitochondrial permeability transition （MPT）. Working at the single live cell level, we found that overexpression of VDAC1 triggers MPT at the mitochondrial inner membrane （MIM）. Conversely, silencing VDAC1 ex- pression results in the inhibition of MPT caused by selenite-induced oxidative stress. This MOM-MIM crosstalk was modulated by Cyclosporin A and mitochondrial Cyclophilin D, but not by Bcl-2 and BcI-XL, indicative of PTP operation. VDAC1-dependent MPT engages a positive feedback loop involving reactive oxygen species and p38-MAPK, and secondarily triggers a canonical apoptotic response including Bax activation, cytochrome e release and caspase 3 activation. Our data thus support a model of the PTP complex involving VDAC1 at the MOM, and indicate that VDACl-dependent MPT is an upstream mechanism playing a causal role in oxidative stress-induced apoptosis.展开更多
Soil organic matter (SOM) plays an important role in the Se dynamics in soil. The potential effects of vermicompost and digestate as important sources of SOM on selenium (Se) mobility were assessed in this study. Thre...Soil organic matter (SOM) plays an important role in the Se dynamics in soil. The potential effects of vermicompost and digestate as important sources of SOM on selenium (Se) mobility were assessed in this study. Three soils differing in their physicochemical parameters, fluvisol, chernozem, and luvisol, were chosen, and three types of vermicomposts based on various bio-waste materials as digestate (vermicompost 1), kitchen waste with woodchips (vermicompost 2), and garden bio-waste (vermicompost 3) were used due to their high organic matter content. Additionally, digestate samples alone were applied. To evaluate the potential effect of vermicompost application on sorption characteristics of soils, batch sorption experiments were performed. The results showed a predominant effect on Se species in the soils, where selenite sorbed more intensively compared to selenate, regardless of the soil and ameliorative material applied. In the control, the soil sorption ability of selenite tended to decrease in the order: fluvisol > luvisol > chernozem. However, these differences were not significant. Moreover, the effects of the ameliorative materials depended on both soil and amendment used. In fluvisol, all the amendment applications resulted in a decrease in distribution coefficient ( K d values) of Se, whereas in chernozem, this effect was observed only for the digestate-based vermicompost 1. Increasing K d levels were reported in luvisol treated with digestate;the application of garden bio-waste-based vermicompost 3 tended to decrease the K d values. Further studies are required on long-term effects of these amendments on Se mobility in soils and the role of individual organic matter fractions in this context.展开更多
Biological dissimilatory reduction of selenite （SeO3^2-） to elemental selenium （Se^0） is common, but the mineral formation and the biogenic process remain uncertain. In this study, we examined the Se^0 formation d...Biological dissimilatory reduction of selenite （SeO3^2-） to elemental selenium （Se^0） is common, but the mineral formation and the biogenic process remain uncertain. In this study, we examined the Se^0 formation during the selenite bioreduction by Bacillus licheniformis SeRB-1 through transmission electron microscope （TEM）, energy-dispersive spectrometry （EDS） and X-ray absorption fine structure （XAFS） techniques. Results showed that the reduction process occurred mostly during the exponential phase and early stationary phase, whilst the elemental selenium was produced in these periods. From the TEM images and polyaerylamide gel eleetropheresis, it is known that the Se^0 granule formation is a biologically-induced type, and the cell envelopes are the main biomineralization positions, and particles may go through a process from nucleation to crystallization, under the control of microbes. In fact, the minerals are spherical nanoparticles, occurring as a microcrystal or amorphous form. It is vital to recognize which kinds of proteins and/or polysaccharides act as a template to direct nanoparticle nucleation and growth？ This should focus for further studies. This study may shed light on the process of formation of Se（0） nanosphere.展开更多
Objective To explore the effects and mechanisms of ascorbic acid (AA) and sodium selenite (SS) on growth inhibition and redifferentiation in human gastric cancer cells. Methods In the present study, trypan blue dye...Objective To explore the effects and mechanisms of ascorbic acid (AA) and sodium selenite (SS) on growth inhibition and redifferentiation in human gastric cancer cells. Methods In the present study, trypan blue dye exclusion method was used to determine the cell growth curve and mitotic index, cell electrophoresis and colonogenic potential were used as the indexes of redifferentiation. In order to find out the mechanisms of redifferentiation, the activities of superoxide dismutase (SOD), glutathione peroxidase (GPX) and catalase (CAT) were assayed, the content of malondialdehyde (MDA), reduced glutathione (GSH) and H2O2 were evaluated. Results After treatment with AA 3 mol/L + SS 2μmol/L, the growth rate and mitotic index of human gastric cancer cells (MGc-803) decreased remarkably. The indexes related with cell malignancy were alleviated. For example, cell surface charge was obviously decreased, the electrophoresis rate was dropped from 2.21 to 1.15μm·s-1·V-1·cm-1. The indexes related with cell redifferentiation were promoted. For example, the colonogenic potential was decreased to 93.5%. These results indicated that redifferentiation of human gastric cancer cells was successfully induced by AA + SS. The activities of SOD and GPX were significantly higher, while the activity of CAT was slower in treated group than that in the control. The content of MDA was slightly decreased, GSH was sharply decreased, and H2O2 content was dramatically increased. Conclusion These results indicated that combination of ascorbic acid and sodium selenite may induce the redifferentiation of human gastric cancer cells and inhibit cell growth by virtue of enhancing the activities of antioxidative enzymes and inducing the formation of H2O2, and altering the cell redox status. Combination of ascorbic acid and sodium selenite may be a potent anticancer agent for human gastric cancer.展开更多
AIM To assess the effect of sodium selenite on the severity of dextran sulfate sodium(DSS)-induced colitis in C57BL/6 mice.METHODS Mice were randomly divided into four groups(n = 10/group): normal group, selenium(Se) ...AIM To assess the effect of sodium selenite on the severity of dextran sulfate sodium(DSS)-induced colitis in C57BL/6 mice.METHODS Mice were randomly divided into four groups(n = 10/group): normal group, selenium(Se) group, chronic colitis group, and Se + chronic colitis group. The mice were sacrificed on day 26. Survival rates, clinical symptoms, colon length, and histological changes were determined. The percentages and absolute numbers of immune system cells in the lamina propria lymphocytes(LPL) of the colon, the expression of m RNA in colon tissue, and the concentrations of Th1, Th17, and Treg cytokines in LPL from the large intestine, were measured.RESULTS Se significantly ameliorated the symptoms of colitis and histological injury(P < 0.05 each), increasing the proportions of neutrophils and CD4+ CD25+ T cells(P < 0.05 each) and decreasing the proportions of γδT cells, CD4+, CD4+CD44+, and CD4+ CD69+ T cells in LPL(P < 0.05 each). Moreover, Se reduced the expression of IL-6, IFN-γ, IL-17 A, IL-21, T-bet, and RORγt(P < 0.05 each), but enhanced the expression of IL-10 and Foxp3(P < 0.05 each). CONCLUSION These results suggest that Se protects against DSSinduced chronic colitis perhaps by increasing the number of CD4(+)CD25(+) Tregs that suppress the secretion of proinflammatory cytokines and populations of Th1, Th17, and γδT cells.展开更多
AIM: To study the combinative effects of nanocerium and selenium in a murine model of diabetes. METHODS: Cerium oxide (CeO2) nanoparticles (60 mg/kg per day) and sodium selenite (5 μmol/kg per day) aloneor in combina...AIM: To study the combinative effects of nanocerium and selenium in a murine model of diabetes. METHODS: Cerium oxide (CeO2) nanoparticles (60 mg/kg per day) and sodium selenite (5 μmol/kg per day) aloneor in combination, or the metal form of CeO2 (60 mg/kg) were administered for 2 wk by intraperitoneal injection to streptozotocin-induced diabetic rats. At the end of treatment blood was collected, liver tissue dissected and then oxidative stress markers, extent of energy depletion and lipid prof ile were evaluated.RESULTS: Antioxidant enzymes and high density lipoprotein decreased whereas oxidative stress, adenosine diphosphate/adenosine triphospahte levels, cholesterol, triglyceride and low density lipoprotein increased on induction of diabetes. All were improved by a combination of nanocerium and sodium selenite. There was a relative amelioration by CeO2 nanoparticles or sodium selenite alone, but the metal form of CeO2 showed no signif icant improvement. CONCLUSION: The combination of nanocerium and sodium selenite is more effective than either alone in improving diabetes-induced oxidative stress.展开更多
A novel three-dimensional（3-D） compound [Cd4（SeO3）2Cl4（H2O）]n（1） was prepared from a hydrothermal reaction and structurally characterized.Compound 1 crystallizes in the space group Fmmm of the orthorhombic sys...A novel three-dimensional（3-D） compound [Cd4（SeO3）2Cl4（H2O）]n（1） was prepared from a hydrothermal reaction and structurally characterized.Compound 1 crystallizes in the space group Fmmm of the orthorhombic system with eight formula units in a cell：a = 15.5165（4）,b = 17.5090（9）,c = 7.3318（5） ,V = 1991.9（2） 3,Cd4Cl4H2O7Se2,Mr = 863.38,Dc = 5.758 g/cm3,S = 1.075,μ（MoKα） = 16.820 mm-1,F（000） = 3088,R = 0.0427 and wR = 0.1220.Compound 1 features a 3-D structure with the cadmium atoms having two different coordination environments,i.e.,six-and eight-coordination geometries.Two different chain-like structures of cadmium-oxo polyhedra are interconnect to each other to give a 2-D layer of [Cd4（SeO3）2（H2O）]n4n＋.Between the [Cd4（SeO3）2（H2O）]n4n＋ layers is a novel chloride layer.A 3-D framework is constructed from these [Cd4（SeO3）2（H2O）]n4n＋ layers linked by the chloride layers.展开更多
基金supported by the National Natural Science Foundation of China(grant:No.29977014)China Capital Investment,Ltd.,in Shanghai.
文摘Chitosans reacted with selenious acid to prepare chitosan hydrogen selenites,which were found to be growth-inhibitory against sarcoma 180 solid tumor.The results indicated that the activity also depended on the molecular weight of chitosan supports.
基金Supported by the Natural Science Foundation of Henan Institute of Science and Technology (No. 06038)
文摘Three novel vanadium selenites with the formulae [（VO2）（1,10-phenanthtoline）（SeO3H）]2 1, [（VO2）（2,2′-bipyridine）]2（SeO3） 2 and [（VO）（H2O）（SeO3）2]2（HaEDD） 3 （EDD = N1,N1′-（ethane-1,2-diyl）diethane-1,2-diamine） were hydrothermally synthesized, and characterized with elemental analysis, FT-IR spectrum, Raman spectrum, TG-DTA analysis, EPR spectra, and single-crystal X-ray diffraction analysis. Compound I belongs to the triclinic system, space group P1^- with a = 7.7527（5）, b = 9.5345（10）, c = 9.8192（8） A^°, α = 92.712（3）, β = 105.540（3）, γ = 108.154（4）°, V = 657.66（1） A^°^3, Mr = 782.22, Z = 1, F（000） = 384,μ（MoKa） = 3.544 mm^-1, R = 0.0432 and wR = 0.1142; Compound 2 is of orthorhombic system, space group F212121 with a = 7.6574（15）, b = 14.916（3）, c = 19.085（4） A, V = 2179.8（8） Aa, Mr = 605.21, Z = 4, F（000） = 1200, μ（MoKa） = 2.579 mm^-1, R = 0.0338 and wR = 0.0658; Compound 3 belongs to the triclinic system, space group P1^- with a = 9.247（2）, b = 9.659（2）, c = 7.2651（19） A^°, α = 98.171（7）, β = 103.709（5）, γ = 114.712（13）°, V = 550.9（2） A^°^3, Mr = 828.03, Z = 1, F（000） = 400, μ（MoKa） = 7.537 mm^-1, R = 0.0641 and wR = 0.2118. Compound 1 is constructed from alternating corner-shared [VO4N2] octahedra and SeO3H units, forming a dimeric vanadium unit. These assemblies are further linked into an infinite chain via hydrogen bonds along the a axis. In the structure of 2, two distinct V centers form centrosymmetric [V2O6N4] clusters through edge-sharing, and the SeO3 unit serves as a capping unit to fix the oxovanadate cluster. In the structure of 3, each [VO6] octahedron shares four oxygen atoms with adjacent Se atoms, while every SeO3 unit shares two oxygen atoms with neighboring V atoms. This connectivity of alternating VO6 and SeO3 units results in a joint-like chain. Based on the TGA analysis, these three compounds are thermally stable under 200℃ .
基金supported by the National Natural Science Foundation of China(Nos.22475215,22031009 and 21921001)the NSF of Fujian Province(Nos.2023J01216,2024J010039)the Selfdeployment Project Research Program of Haixi Institutes,Chinese Academy of Sciences(No.CXZX-2022-GH06).
文摘Exploring new material systems and enhancing the birefringence of compounds is a highly valuable endeavor.In this study,we introduce a novel method to enhance the birefringence of inorganic compounds by inducing structural alignment through linear groups and fluoride ions.We report on two new compounds:HgGa_(2)(SeO_(3))_(4) and Hg_(2)Ga(Se_(O)_(3))_(2)F.HgGa_(2)(SeO_(3))_(4) crystallizes in a non-centrosymmetric(NCS)space group,exhibiting a second harmonic generation(SHG)efficiency of approximately 60% that of commercial KH2PO4(KDP),with a birefringence of 0.032@546 nm.Hg_(2)Ga(Se_(O)_(3))_(2)F,on the other hand,crystallizes in a centrosymmetric space(CS)group and represents the first reported HgI-based selenite birefringent material.Due to the influence of the linear group Hg_(2)O_(2),its birefringence is significantly enhanced to 0.111@546 nm,which is 3.5 times that of HgGa_(2)(SeO_(3))_(4).Moreover,both compounds demonstrate high stability and a broad optical transparency window.These findings indicate that Hg_(2)Ga(Se_(O)_(3))_(2)F is a promising candidate for birefringent material in the mid-infrared(MIR)range.Our research provides an innovative strategy for improving the birefringence of compounds.
基金Supported by National Natural Science Foundation of China(31270674)Science and Technology Plan Project of Zhaoqing City(2019N012)National Undergraduate Science and Technology Innovation Training Program of China(202210580007).
文摘[Objectives]To explore the effect of selenium(Se)on inhibiting embryo abortion and enhancing seedling cultivation quality of Red sandalwood(Pterocarpus santalinus).[Methods]Based on prior cultivation practices and experimental research,three categories comprising 13 forest soil nutrient management schemes were designed to investigate the synergistic effects of Se,NPK compound fertilizers,and enzyme-microbe fermented organic fertilizers(EFOF)on embryo abortion,winged pod development,and seedling quality of Red sandalwood.[Results]Increasing the Se content in the soil,particularly in the form of selenite/Se(IV),within one month following the harvest of Red sandalwood pods and within two months prior to flower withering,significantly reduced embryo abortion percentage(EAP),and consequently improved seed quality and yield per plant.The effect of Se application was markedly greater than that of the single application of nitrogen(N),phosphorus(P),potassium(K),boron(B)fertilizers,or organic fertilizers.Furthermore,when Se was applied in combination with NPK compound fertilizers and EFOF,these beneficial effects were significantly enhanced.When Se(IV)was applied individually,the EAP decreased by 62.4%,reaching 24.8% at 8 weeks after flower withering(compared to 65.9%in the unmanaged control,UMC).Following winged pod maturation,the percentage of empty winged pods(PEWP)declined by 65.2% to 16.8%(UMC:48.2%),the average individual winged pod weight(IWPW)increased by 69.1%to 0.690 g per fruit(UMC:0.408 g),and the winged pod yield(WPY)rose by 214.8% to 4.03 kg(UMC:1.28 kg).Additionally,the blasted seed percentage(BSP)was reduced by 51.2% to 29.9%(UMC:61.3%),and the 100-seed weight(HSW)increased by 96.0%to 8.37 g(UMC:4.27 g).Following sowing in the nursery,the seedling emergence rate(SER)increased by 6.57-fold,reaching 59.8%(UMC:7.9%).Additionally,the whole plant biomass of 6-month-old seedlings increased by 52.9%,attaining 1.56 g(UMC:1.02 g).The combined application of EFOF+NPK+Se(IV)significantly reduced the EAP,PEWP,and BSP by 56.5%,46.0%,and 56.3%,respectively,compared to the single application of Se(IV).Furthermore,these percentages decreased by 79.7%,78.9%,and 71.8%,respectively,relative to the single application of NPK compound fertilizers,and by 79.0%,74.5%,and 72.1%,respectively,compared to the single application of EFOF.Additionally,the SER increased by 34.6%,141.0%,and 287.0%,respectively,when compared to the single application of Se(IV),NPK compound fertilizers,and EFOF.[Conclusions]Enhancing the nutrient status of forest soils,particularly the concentration of Se(IV),constitutes a critical technical approach to improving the resistance of Red sandalwood to low-temperature stress during its flowering and fruiting stages,thereby preventing embryo abortion.
文摘Selenium(Se)is a nutrient that is considered beneficial for plants,because its improvement in growth,yield and quality helps plants to mitigate stress.The objective of this research was to evaluate the application of sodium selenite(Na2SeO3),nanoparticles(SeNPs)and microparticles(SeMPs)of Se in cucumber seedlings,via two experiments:one with seed priming and the other with foliar application of Sematerials.The doses used were:0,0.1,0.5,1.0,1.5 and 3.0 mg⋅L^(−1),for each form of Se and for each form of application.Treatment 0 consisted of the application of distilled water,which was used as a control.The results indicated that the SeMPs treatment at 3.0 mg⋅L^(−1)for seed priming had the greatest effect on stem diameter and leaf area.Foliar application of SeMPs at 1.5 mg⋅L^(−1)was the most effective at increasing the leaf area.In terms of fresh and dry biomass(aerial,root and total)for seed priming,all the treatments were superior to the control,and SeMPs at 1.5 and 3.0 mg⋅L^(−1)caused the greatest effects.With foliar application,fresh root biomass improved to a greater extent with the SeMPs treatment at 3.0 mg⋅L^(−1),and dry biomass(aerial,root and total)increased with the SeMPs at 1.0 and 3.0 mg⋅L^(−1).With respect to the photosynthetic pigments,proteins,phenols and minerals,the Se treatments,both for seed priming and foliar application,caused increases and decreases;however,reduced glutathione(GSH)increased with treatments in both forms of application.The Se concentration in the seedlings increased as the dose of Se material increased,and greater accumulation was achieved with foliar application of SeNPs and SeMPs.The results indicate that the use of Se materials is recommended,mainly the use of SeMPs,which improved the variables studied.This opens new opportunities for further studies with SeMPs,as little information is available on their application in agricultural crops.
基金supported by the National Natural Science Foundation of China(No.32370130).
文摘Microbial selenite(Se(Ⅳ)) reduction to elemental selenium nanoparticles(SeNPs) and chromate(Cr(Ⅵ)) remediation constitute effective detoxification processes. The strain Bacillus wiedmannii ES2-45 can efficiently reduce 5 mmol/L Se(Ⅳ) into SeNPs over 14 h and 1 mmol/L Cr(Ⅵ) within 36 h. Proteomic analysis and qRT-PCR revealed that reductases, including dithiol oxidoreductase(DsbA), Fe-S biosynthesis domain-containing protein(Fes),and aldose-6-phosphate reductase(Aldo), and bacillithiol(BSH) were involved in Se(Ⅳ) reduction. Heterologous expression further confirmed the Se(Ⅳ)-reducing function of three genes and enhanced the Se(Ⅳ) and Cr(Ⅵ) resistance ability. Moreover, the difference between Se(Ⅳ) treatments and controls both intra-and extra-cellular BSH concentration per biomass indicated that BSH contributes to Se(Ⅳ) reduction. Selenium-fortified rice was obtained by foliar spray of SeNPs synthesized by the strain ES2-45. To the best of our knowledge, DsbA and Aldo reductase were firstly verified for the role in Se(Ⅳ) reduction and Cr(Ⅵ)resistance. Importantly, it is a promising strategy that B. wiedmannii ES2-45 is served as an efficient bacterium for SeNP synthesis, selenium biofortification and heavy metal bioremediation.
文摘Traditional studies on transforming selenate and selenite are often limited by static measurements and low spatial resolution.They do not fully consider the impact of moisture content.This paper uses the DGT(diffusive gradients in thin films)technique to deeply explore how moisture changes affect the transformation of selenate and selenite in the environment(changes in properties over time).First,representative soil samples(loess)are prepared,and their moisture content is adjusted.Fixed concentrations of selenate and selenite are added,and then the DGT device simulates their migration in the natural environment.The experiment covers drought,moisture,and high moisture environments,and the experiment is repeated under each condition to ensure the accuracy of the data.The sample quality is verified and further analyzed by ion chromatography(IC)and atomic absorption spectroscopy(AAS).This article uses DGT technology to study the influence of moisture content on the migration and transformation of selenate and selenite in soil.Results indicate that increased moisture content leads to higher concentrations,diffusion rates,and DGT capture efficiency of both selenium species,highlighting the importance of moisture in their environmental behavior.When the moisture content increased from 25%to 65%,the coefficient of variation of selenate and selenite increased.The DGT technique proved effective in capturing spatial heterogeneity and providing high-precision measurements,offering robust data to advance research on selenium behavior in soils.
基金Project supported by the National Natural Science Foundation of China (No. 40371063)the National Key Basic Research Support Foundation of China (No. G1999011808).
文摘Two japonica rice （Oryza sativa L.） cultivars, Xiushui 48 and S. Andrea, differing in their ability to accumulate Se in the grain （as high as a three-fold difference）, were compared for selenium （Se） accumulation in their shoots when their growth media was supplied with different forms of Se. Results indicated that when treated with 0.25μmol L^-1 Na2SeO3, Xiushui 48 accumulation of Se in the shoots was significantly more rapid （P〈0.05） than S. Andrea, probably because of greater Se uptake and transport in Xiushui 48. Xiushui 48 rice seedlings had a higher shoot-Se accumulation rate and absorbed selenocysteine （Se-Cys） more rapidly than S. Andrea seedlings. However, when treated with Se as 0.25μmol L^-1 selenomethionine （Se-Met）, the S. Andrea seedlings＇ accumulation rate was significantly greater （P〈0.05） than that of Xiushui 48. Possibly, the high Se accumulation rate of Xiushui 48 seedling shoots compared to S. Andrea shoots was the result of a higher capacity of Xiushui 48 to transform selenite to organic Se compounds and a higher selenite uptake rate.
基金Project supported by the National Natural Science Foundation of China(Nos.49971046 and 49831005).
文摘Hydroxyl release of red soil and latosol surfaces was quantitatively measuredusing a self-made constant pH automated titration instrument, to study the changes of hydroxylrelease with different added selenite amounts and pH levels, and to study the effects ofelectrolytes on hydroxyl release. Hydroxyl release increased with the selenite concentration, with arapid increase at a low selenite concentration while slowing down at a high concentration. The pHwhere maximum of hydroxyl release appeared was not constant, shifting to a lower valus withincreasing selenite concentration. Hydroxyl release decreased with increasing electrolyteconcentration, and the decrease was very rapid at a low electrolyte concentration but slow at a highelectrolyte concentration. For NaClO_4, NaCl and Na_2SO_4, hydroxyl release was in the order ofNaClO_4 > NaCl >> Na_2SO_4, and the difference was very significant. But for NaCl, KCl and CaCl_2,the order of hydroxyl release was NaCl > KCl > CaCl_2, and the difference was smaller. The amount ofhydroxyl release from Xuwen latosol was greater than that from Jinxian red soil. Hydroxyl releaseexisted in a wider range of pH with Xuwen latosol than with Jinxian red soil, due to theirdifference in soil properties. However, both soils had similar curves of hydroxyl release,indicating the common characteristics of variable charge soils.
基金supported by the National Natural Science Foundation of China(No.41771355)the Anhui Provincial Natural Science Foundation(No.1508085SMC211)the Key Project of Outstanding Young Talent Support Program in Universities of Anhui Province(No.gxyqZD2016025)
文摘Microbes play important roles in the transport and transformation of selenium(Se) in the environment, thereby influencing plant resistance to Se and Se accumulation in plant. The objectives are to characterize the bacteria with high Se tolerance and reduction capacity and explore the significance of microbial origins on their Se tolerance, reduction rate and efficiency. Two bacterial strains were isolated from a naturally occurred Se-rich soil at tea orchard in southern Anhui Province, China. The reduction kinetics of selenite was investigated and the reducing product was characterized using scanning electron microscopy and transmission electron microscopy-energy dispersive spectroscopy. The bacteria were identified as Lysinibacillus xylanilyticus and Lysinibacillus macrolides,respectively, using morphological, physiological and molecular methods. The results showed that the minimal inhibitory concentrations(MICs) of selenite for L. xylanilyticus and L. macrolides were 120 and 220 mmol/L, respectively, while MICs of selenate for L.xylanilyticus and L. macrolides were 800 and 700 mmol/L, respectively. Both strains aerobically reduced selenite with an initial concentration of 1.0 mmol/L to elemental Se nanoparticles(SeNPs) completely within 36 hr. Biogenic SeNPs were observed both inside and outside the cells suggesting either an intra-or extracellular reduction process. Our study implied that the microbes from Se-rich environments were more tolerant to Se and generally quicker and more efficient than those from Se-free habitats in the reduction of Se oxyanions. The bacterial strains with high Se reduction capacity and the biological synthesized Se NPs would have potential applications in agriculture, food, environment and medicine.
基金The National Natural Science Foundation of China,No.30570480
文摘AIM: To study liver cell apoptosis caused by the toxicity of selenium and observe the alteration of choline compounds using in vitro 9.4T high resolution magnetic resonance spectroscopy. METHODS: Twenty male Wistar rats were randomly divided into two groups. The rats in the treatment group were intraperitoneally injected with sodium selenite and the control group with distilled water. All rats were sacrifi ced and the livers were dissected. 1H-MRS data were collected using in vitro 9.4T high resolution magnetic resonance spectrometer. Spectra were processed using XWINNMR and MestRe-c 4.3. HE and TUNEL staining was employed to detect and confi rm the change of liver cells. RESULTS: Good 1H-MR spectra of perchloric acid extract from liver tissue of rats were obtained. The conventional metabolites were detected and assigned. Concentrations of different ingredient choline compounds in treatment group vs control group were as follows: total choline compounds,5.08 ± 0.97 mmol/L vs 3.81 ± 1.16 mmol/L (P = 0.05); and free choline,1.07 ± 0.23 mmol/L vs 0.65 ± 0.20 mmol/L (P = 0.00). However,there was no statistical signif icance between the two groups. The hepatic sinus and cellular structure of hepatic cells in treatmentgroup were abnormal. Apoptosis of hepatic cells was confi rmed by TUNEL assay. CONCLUSION: High dose selenium compounds can cause the rat liver lesion and induce cell apoptosis in vivo. High resolution 1H-MRS in vitro can detect diversified metabolism. The changing trend for different ingredient of choline compounds is not completely the same at early period of apoptosis.
基金supported by the National Natural Science Foundation of China, No.81870979(to JJL)the Scientific Research Foundation of China Rehabilitation Research Center, No.2020-02(to JJL)the Natural Science Foundation of Changsha, No.kq2014285(to YXC)
文摘Ferroptosis is a recently discovered form of iron-dependent cell death,which occurs during the pathological process of various central nervous system diseases or injuries,including secondary spinal cord injury.Selenium has been shown to promote neurological function recovery after cerebral hemorrhage by inhibiting ferroptosis.However,whether selenium can promote neurological function recovery after spinal cord injury as well as the underlying mechanism remain poorly understood.In this study,we injected sodium selenite(3μL,2.5μM)into the injury site of a rat model of T10 vertebral contusion injury 10 minutes after spinal cord injury modeling.We found that sodium selenite treatment greatly decreased iron concentration and levels of the lipid peroxidation products malondialdehyde and 4-hydroxynonenal.Furthermore,sodium selenite increased the protein and mRNA expression of specificity protein 1 and glutathione peroxidase 4,promoted the survival of neurons and oligodendrocytes,inhibited the proliferation of astrocytes,and promoted the recovery of locomotive function of rats with spinal cord injury.These findings suggest that sodium selenite can improve the locomotive function of rats with spinal cord injury possibly through the inhibition of ferroptosis via the specificity protein 1/glutathione peroxidase 4 pathway.
文摘Voltage-dependent anion channel （VDAC）I is the main channel of the mitochondrial outer membrane （MOM） and it has been proposed to be part of the permeability transition pore （PTP）, a putative multiprotein complex candidate agent of the mitochondrial permeability transition （MPT）. Working at the single live cell level, we found that overexpression of VDAC1 triggers MPT at the mitochondrial inner membrane （MIM）. Conversely, silencing VDAC1 ex- pression results in the inhibition of MPT caused by selenite-induced oxidative stress. This MOM-MIM crosstalk was modulated by Cyclosporin A and mitochondrial Cyclophilin D, but not by Bcl-2 and BcI-XL, indicative of PTP operation. VDAC1-dependent MPT engages a positive feedback loop involving reactive oxygen species and p38-MAPK, and secondarily triggers a canonical apoptotic response including Bax activation, cytochrome e release and caspase 3 activation. Our data thus support a model of the PTP complex involving VDAC1 at the MOM, and indicate that VDACl-dependent MPT is an upstream mechanism playing a causal role in oxidative stress-induced apoptosis.
基金the Czech Science Foundation (GACR) for their financial support (Project No. 1304580S)
文摘Soil organic matter (SOM) plays an important role in the Se dynamics in soil. The potential effects of vermicompost and digestate as important sources of SOM on selenium (Se) mobility were assessed in this study. Three soils differing in their physicochemical parameters, fluvisol, chernozem, and luvisol, were chosen, and three types of vermicomposts based on various bio-waste materials as digestate (vermicompost 1), kitchen waste with woodchips (vermicompost 2), and garden bio-waste (vermicompost 3) were used due to their high organic matter content. Additionally, digestate samples alone were applied. To evaluate the potential effect of vermicompost application on sorption characteristics of soils, batch sorption experiments were performed. The results showed a predominant effect on Se species in the soils, where selenite sorbed more intensively compared to selenate, regardless of the soil and ameliorative material applied. In the control, the soil sorption ability of selenite tended to decrease in the order: fluvisol > luvisol > chernozem. However, these differences were not significant. Moreover, the effects of the ameliorative materials depended on both soil and amendment used. In fluvisol, all the amendment applications resulted in a decrease in distribution coefficient ( K d values) of Se, whereas in chernozem, this effect was observed only for the digestate-based vermicompost 1. Increasing K d levels were reported in luvisol treated with digestate;the application of garden bio-waste-based vermicompost 3 tended to decrease the K d values. Further studies are required on long-term effects of these amendments on Se mobility in soils and the role of individual organic matter fractions in this context.
基金financially supported by the National Natural Science Foundation of China (No. 41273029)National Basic Research Program of China (No. 2014CB238903)
文摘Biological dissimilatory reduction of selenite （SeO3^2-） to elemental selenium （Se^0） is common, but the mineral formation and the biogenic process remain uncertain. In this study, we examined the Se^0 formation during the selenite bioreduction by Bacillus licheniformis SeRB-1 through transmission electron microscope （TEM）, energy-dispersive spectrometry （EDS） and X-ray absorption fine structure （XAFS） techniques. Results showed that the reduction process occurred mostly during the exponential phase and early stationary phase, whilst the elemental selenium was produced in these periods. From the TEM images and polyaerylamide gel eleetropheresis, it is known that the Se^0 granule formation is a biologically-induced type, and the cell envelopes are the main biomineralization positions, and particles may go through a process from nucleation to crystallization, under the control of microbes. In fact, the minerals are spherical nanoparticles, occurring as a microcrystal or amorphous form. It is vital to recognize which kinds of proteins and/or polysaccharides act as a template to direct nanoparticle nucleation and growth？ This should focus for further studies. This study may shed light on the process of formation of Se（0） nanosphere.
文摘Objective To explore the effects and mechanisms of ascorbic acid (AA) and sodium selenite (SS) on growth inhibition and redifferentiation in human gastric cancer cells. Methods In the present study, trypan blue dye exclusion method was used to determine the cell growth curve and mitotic index, cell electrophoresis and colonogenic potential were used as the indexes of redifferentiation. In order to find out the mechanisms of redifferentiation, the activities of superoxide dismutase (SOD), glutathione peroxidase (GPX) and catalase (CAT) were assayed, the content of malondialdehyde (MDA), reduced glutathione (GSH) and H2O2 were evaluated. Results After treatment with AA 3 mol/L + SS 2μmol/L, the growth rate and mitotic index of human gastric cancer cells (MGc-803) decreased remarkably. The indexes related with cell malignancy were alleviated. For example, cell surface charge was obviously decreased, the electrophoresis rate was dropped from 2.21 to 1.15μm·s-1·V-1·cm-1. The indexes related with cell redifferentiation were promoted. For example, the colonogenic potential was decreased to 93.5%. These results indicated that redifferentiation of human gastric cancer cells was successfully induced by AA + SS. The activities of SOD and GPX were significantly higher, while the activity of CAT was slower in treated group than that in the control. The content of MDA was slightly decreased, GSH was sharply decreased, and H2O2 content was dramatically increased. Conclusion These results indicated that combination of ascorbic acid and sodium selenite may induce the redifferentiation of human gastric cancer cells and inhibit cell growth by virtue of enhancing the activities of antioxidative enzymes and inducing the formation of H2O2, and altering the cell redox status. Combination of ascorbic acid and sodium selenite may be a potent anticancer agent for human gastric cancer.
基金Supported by National Natural Science Foundation of China,No.31370921Natural Science Foundation of Liaoning Province,No.2015020515
文摘AIM To assess the effect of sodium selenite on the severity of dextran sulfate sodium(DSS)-induced colitis in C57BL/6 mice.METHODS Mice were randomly divided into four groups(n = 10/group): normal group, selenium(Se) group, chronic colitis group, and Se + chronic colitis group. The mice were sacrificed on day 26. Survival rates, clinical symptoms, colon length, and histological changes were determined. The percentages and absolute numbers of immune system cells in the lamina propria lymphocytes(LPL) of the colon, the expression of m RNA in colon tissue, and the concentrations of Th1, Th17, and Treg cytokines in LPL from the large intestine, were measured.RESULTS Se significantly ameliorated the symptoms of colitis and histological injury(P < 0.05 each), increasing the proportions of neutrophils and CD4+ CD25+ T cells(P < 0.05 each) and decreasing the proportions of γδT cells, CD4+, CD4+CD44+, and CD4+ CD69+ T cells in LPL(P < 0.05 each). Moreover, Se reduced the expression of IL-6, IFN-γ, IL-17 A, IL-21, T-bet, and RORγt(P < 0.05 each), but enhanced the expression of IL-10 and Foxp3(P < 0.05 each). CONCLUSION These results suggest that Se protects against DSSinduced chronic colitis perhaps by increasing the number of CD4(+)CD25(+) Tregs that suppress the secretion of proinflammatory cytokines and populations of Th1, Th17, and γδT cells.
基金Supported by a grant from Tehran University of Medical Science, No. 11250 (in part)
文摘AIM: To study the combinative effects of nanocerium and selenium in a murine model of diabetes. METHODS: Cerium oxide (CeO2) nanoparticles (60 mg/kg per day) and sodium selenite (5 μmol/kg per day) aloneor in combination, or the metal form of CeO2 (60 mg/kg) were administered for 2 wk by intraperitoneal injection to streptozotocin-induced diabetic rats. At the end of treatment blood was collected, liver tissue dissected and then oxidative stress markers, extent of energy depletion and lipid prof ile were evaluated.RESULTS: Antioxidant enzymes and high density lipoprotein decreased whereas oxidative stress, adenosine diphosphate/adenosine triphospahte levels, cholesterol, triglyceride and low density lipoprotein increased on induction of diabetes. All were improved by a combination of nanocerium and sodium selenite. There was a relative amelioration by CeO2 nanoparticles or sodium selenite alone, but the metal form of CeO2 showed no signif icant improvement. CONCLUSION: The combination of nanocerium and sodium selenite is more effective than either alone in improving diabetes-induced oxidative stress.
基金supported by the NSF of Jiangxi Province (200007GQH1685,2008GQH0001)
文摘A novel three-dimensional（3-D） compound [Cd4（SeO3）2Cl4（H2O）]n（1） was prepared from a hydrothermal reaction and structurally characterized.Compound 1 crystallizes in the space group Fmmm of the orthorhombic system with eight formula units in a cell：a = 15.5165（4）,b = 17.5090（9）,c = 7.3318（5） ,V = 1991.9（2） 3,Cd4Cl4H2O7Se2,Mr = 863.38,Dc = 5.758 g/cm3,S = 1.075,μ（MoKα） = 16.820 mm-1,F（000） = 3088,R = 0.0427 and wR = 0.1220.Compound 1 features a 3-D structure with the cadmium atoms having two different coordination environments,i.e.,six-and eight-coordination geometries.Two different chain-like structures of cadmium-oxo polyhedra are interconnect to each other to give a 2-D layer of [Cd4（SeO3）2（H2O）]n4n＋.Between the [Cd4（SeO3）2（H2O）]n4n＋ layers is a novel chloride layer.A 3-D framework is constructed from these [Cd4（SeO3）2（H2O）]n4n＋ layers linked by the chloride layers.
