The highly-dispersed iron element decorated Ni foam was prepared by simple immersion in a ferric nitrate solution at room temperature without using acid etching, and characterized by X-ray powder diffraction(XRD), sca...The highly-dispersed iron element decorated Ni foam was prepared by simple immersion in a ferric nitrate solution at room temperature without using acid etching, and characterized by X-ray powder diffraction(XRD), scanning electron microscopy(SEM), EDAX spectrum(EDAX mapping) and Raman spectroscopy. The EDAX spectrum illustrated that iron element was highly-dispersed over the entire surface of nickel foam, and the Raman spectroscopy revealed that both Ni-O and Fe-O bonds were formed on the surface of the as-prepared electrode. Moreover, the iron element decorated Ni foam electrode can be used as non-enzymatic glucose sensor and it exhibits not only an ultra-wide linear concentration range of 1-18 mmol/L with an outstanding sensitivity of 1.0388 m A·mmol/(L·cm2), but also an excellent ability of stability and selectivity. Therefore, this work presents a simple yet effective approach to successfully modify Ni foam as non-enzymatic glucose sensor.展开更多
AIM:To study the role of hepcidin in hereditary hyperferritinemia cataract syndrome(HHCS). METHODS:Six patients from two families with HHCS, confirmed by genetic analysis showing A to G mutation at position+40 in the ...AIM:To study the role of hepcidin in hereditary hyperferritinemia cataract syndrome(HHCS). METHODS:Six patients from two families with HHCS, confirmed by genetic analysis showing A to G mutation at position+40 in the L-ferritin gene,were recruited to undergo serum hepcidin and prohepcidin measurements using radioimmunoassay and enzyme linked immunoassay,respectively,and measurements were compared with levels in serum from 25 healthy volunteers(14 females),mean age 36±11.9 years.RESULTS:The serum hepcidin and prohepcidin levels in patients with HHCS were 19.1±18.6 and 187± 120.9 ng/mL,respectively.Serum ferritin was 1716.3± 376μg/L.Liver biopsy in one patient did not show any evidence of iron overload.Serum hepcidin and prohepcidin values in healthy controls(HCs)were 15.30±15.71 and 236.88±83.68 ng/mL,respectively,while serum ferritin was 110±128.08μg/L.There was no statistical difference in serum hepcidin level between the two cohorts(19.1±18.6 ng/mL vs 15.30±15.71 ng/mL,P= 0.612)using two-tailed t-test. CONCLUSION:Serum hepcidin levels in HHCS patients is similar to that in HCs.Our study suggests that circulating ferritin is not a factor influencing hepcidin synthesis and does not have a role in the iron-sensing mechanism in hepatocytes.展开更多
Glutamic acid and gamma-aminobutyric acid (GABA) influence iron content in the substantia nigra and globus pallidus, although the mechanisms of action remain unclear. The present study measured iron content and chan...Glutamic acid and gamma-aminobutyric acid (GABA) influence iron content in the substantia nigra and globus pallidus, although the mechanisms of action remain unclear. The present study measured iron content and changes in divalent metal transporter 1 (DMT1) and hephaestin expression in the substantia nigra and caudate putamen, and explored the effects of GABA and glutamic acid on iron metabolism. Results demonstrated that iron content and DMT1 non iron response element [DMT1 (-IRE)] expression were significantly greater but hephaestin expression was significantly lower in the caudate putamen of the monosodium glutamate group compared with the control group. No significant difference in iron content was detected between the GABA and control groups. DMT1 (-IRE) expression was significantly reduced, but hephaestin expressiori was significantly increased in the GABA group compared with the control group. In addition, there was no significant difference in tyrosine hydroxylase expression between monosodium glutamate and GABA groups and the control group. These results suggested that glutamate affected iron metabolism in the caudate putamen by increasing DMTI(-IRE) and decreasing hephaestin expression. In addition, GABA decreased DMT1 (-IRE) expression in the caudate putamen.展开更多
Taking double-die ironing for example, the plastic deformation behavior of theworkpiece in multidie ironing process is analysed by the rigid-plastic finite element method(RPFEM).Considering the strain hardening of the...Taking double-die ironing for example, the plastic deformation behavior of theworkpiece in multidie ironing process is analysed by the rigid-plastic finite element method(RPFEM).Considering the strain hardening of the material, the distrbutions of the effective strainrate and hydrostatic stress are obtained. Calculated results and the effect of die argles on thedeformation and ironing force are discussed. The companrson of calculated results with thcoe of ex-poriment shows a good agreement.展开更多
基金Project(2019zzts684)supported by the Fundamental Research Funds for the Central Universities,China。
文摘The highly-dispersed iron element decorated Ni foam was prepared by simple immersion in a ferric nitrate solution at room temperature without using acid etching, and characterized by X-ray powder diffraction(XRD), scanning electron microscopy(SEM), EDAX spectrum(EDAX mapping) and Raman spectroscopy. The EDAX spectrum illustrated that iron element was highly-dispersed over the entire surface of nickel foam, and the Raman spectroscopy revealed that both Ni-O and Fe-O bonds were formed on the surface of the as-prepared electrode. Moreover, the iron element decorated Ni foam electrode can be used as non-enzymatic glucose sensor and it exhibits not only an ultra-wide linear concentration range of 1-18 mmol/L with an outstanding sensitivity of 1.0388 m A·mmol/(L·cm2), but also an excellent ability of stability and selectivity. Therefore, this work presents a simple yet effective approach to successfully modify Ni foam as non-enzymatic glucose sensor.
基金Supported by Research and Development Department,Ealing Hospital NHS Trust,Uxbridge Road,Southall,London,UB13HW,United Kingdom
文摘AIM:To study the role of hepcidin in hereditary hyperferritinemia cataract syndrome(HHCS). METHODS:Six patients from two families with HHCS, confirmed by genetic analysis showing A to G mutation at position+40 in the L-ferritin gene,were recruited to undergo serum hepcidin and prohepcidin measurements using radioimmunoassay and enzyme linked immunoassay,respectively,and measurements were compared with levels in serum from 25 healthy volunteers(14 females),mean age 36±11.9 years.RESULTS:The serum hepcidin and prohepcidin levels in patients with HHCS were 19.1±18.6 and 187± 120.9 ng/mL,respectively.Serum ferritin was 1716.3± 376μg/L.Liver biopsy in one patient did not show any evidence of iron overload.Serum hepcidin and prohepcidin values in healthy controls(HCs)were 15.30±15.71 and 236.88±83.68 ng/mL,respectively,while serum ferritin was 110±128.08μg/L.There was no statistical difference in serum hepcidin level between the two cohorts(19.1±18.6 ng/mL vs 15.30±15.71 ng/mL,P= 0.612)using two-tailed t-test. CONCLUSION:Serum hepcidin levels in HHCS patients is similar to that in HCs.Our study suggests that circulating ferritin is not a factor influencing hepcidin synthesis and does not have a role in the iron-sensing mechanism in hepatocytes.
基金the National Natural Science Foundation of China, No. 30570957the Natural Science Foundation of Hebei Province, No. C2006000152, C2007000251
文摘Glutamic acid and gamma-aminobutyric acid (GABA) influence iron content in the substantia nigra and globus pallidus, although the mechanisms of action remain unclear. The present study measured iron content and changes in divalent metal transporter 1 (DMT1) and hephaestin expression in the substantia nigra and caudate putamen, and explored the effects of GABA and glutamic acid on iron metabolism. Results demonstrated that iron content and DMT1 non iron response element [DMT1 (-IRE)] expression were significantly greater but hephaestin expression was significantly lower in the caudate putamen of the monosodium glutamate group compared with the control group. No significant difference in iron content was detected between the GABA and control groups. DMT1 (-IRE) expression was significantly reduced, but hephaestin expressiori was significantly increased in the GABA group compared with the control group. In addition, there was no significant difference in tyrosine hydroxylase expression between monosodium glutamate and GABA groups and the control group. These results suggested that glutamate affected iron metabolism in the caudate putamen by increasing DMTI(-IRE) and decreasing hephaestin expression. In addition, GABA decreased DMT1 (-IRE) expression in the caudate putamen.
文摘Taking double-die ironing for example, the plastic deformation behavior of theworkpiece in multidie ironing process is analysed by the rigid-plastic finite element method(RPFEM).Considering the strain hardening of the material, the distrbutions of the effective strainrate and hydrostatic stress are obtained. Calculated results and the effect of die argles on thedeformation and ironing force are discussed. The companrson of calculated results with thcoe of ex-poriment shows a good agreement.