Dissimilatory Fe（Ⅲ） reduction is an important process in the geochemical cycle of iron in anoxic environment. As the main products of dissimilatory iron reduction, the Fe（Ⅱ） species accumulation could indicate t...Dissimilatory Fe（Ⅲ） reduction is an important process in the geochemical cycle of iron in anoxic environment. As the main products of dissimilatory iron reduction, the Fe（Ⅱ） species accumulation could indicate the reduction ability. The effects of different green manures on Fe（Ⅲ） reduction in paddy soil were explored based on a 31-year rice-rice-winter green manure cropping experiment. Four treatments were involved, i.e., rice-rice-milk vetch （RRV）, rice-rice-rape （RRP）, rice-rice-ryegrass （RRG） and rice-rice-winter fallow （RRF）. Soils were sampled at flowering stage of milk vetch and rape （S1）, before transplantation （S2）, at tillering （S3）, jointing （S4）, and mature （S5） stages of the early rice, and after the harvest of the late rice （S6）. The contents of TFeHa （HCI-extractable total Fe）, Fe（Ⅱ）HCI （HCI-extractable Fe（Ⅱ） species） and Fe（Ⅲ）HCI （HCI- extractable Fe（Ⅲ） species） were measured. The correlations among those Fe species with selected soil environmental factors and the dynamic characteristics of Fe（Ⅱ）HCI accumulation were investigated. The results showed that TFeHc~ in RRF was significantly higher than those in the green manure treatments at most of the sampling stages. Fe（II）Ha increased rapidly after the incorporation of green manures in all treatments and kept rising with the growth of early rice. Fe（Ⅱ）Ha in RRG was quite different from those in other treatments, i.e., it reached the highest at the S2 stage, then increased slowly and became the lowest one at the S4 and S5 stages. Fe（Ⅲ）Ha showed oppositely, and Fe（Ⅱ）HCI/Fe（Ⅲ）HCI performed similarly to Fe（Ⅱ）HCI The maximum accumulation potential of Fe（Ⅱ）HCI was significantly higher in RRF, while the highest maximum reaction rate of Fe（Ⅱ）Ha accumulation appeared in RRG. Significant correlations were found between the indexes of Fe（Ⅱ）HCI accumulation and soil pH, oxidation-reduction potential （Eh） and total organic acids, respectively. In together, we found that long-term application of green manures decreased the TFeHa in red paddy soils, but promoted the ability of Fe（lll） reduction, especially the ryegrass; Fe（Ⅱ）Ha increased along with the growth of rice and was affected by soil conditions and environmental factors, especially the water and redox ability.展开更多
AIM: To assess whether juvenile chronic ferric iron ingestion limit colitis and dysbiosis at adulthood in rats and mice. METHODS: Two sets of experiments were designed. In the first set, recently weaned mice were eith...AIM: To assess whether juvenile chronic ferric iron ingestion limit colitis and dysbiosis at adulthood in rats and mice. METHODS: Two sets of experiments were designed. In the first set, recently weaned mice were either orally administered ferrous (Fe2+) iron salt or ferric (Fe3+) microencapsulated iron for 6 wk. The last week of experiments trinitrobenzene sulfonic acid (TNBS) colitis was induced. In the second set, juvenile rats received the microencapsulated ferric iron for 6 wk and were also submitted to TNBS colitis during the last week of experiments. In both sets of experiments, animals were sacrificed 7 d after TNBS instillation. Severity of the inflammation was assessed by scoring macroscopic lesions and quantifying colonic myeloperoxidase (MPO) activity. Alteration of the microflora profile was estimated usingquantitative polymerase chain reaction (qPCR) by measuring the evolution of total caecal microflora, Bacteroidetes, Firmicutes and enterobacteria. RESULTS: Neither ferrous nor ferric iron daily exposures at the juvenile period result in any effect in control animals at adulthood although ferrous iron repeated administration in infancy limited weight gain. Ferrous iron was unable to limit the experimental colitis (1.71 ± 0.27 MPO U/mg proteinvs 2.47 ± 0.22 MPO U/mg protein in colitic mice). In contrast, ferric iron significantly prevented the increase of MPO activity (1.64 ± 0.14 MPO U/mg protein) in TNBS-induced colitis. Moreover, this positive effect was observed at both the doses of ferric iron used (75 and 150 mg/kg per day po - 6 wk). In the study we also compared, in both rats and mice, the consequences of chronic repeated low level exposure to ferric iron (75 mg/kg per day po - 6 wk) on TNBS-induced colitis and its related dysbiosis. We confirmed that ferric iron limited the TNBS-induced increase of MPO activity in both the rodent species. Furthermore, we assessed the ferric iron incidence on TNBS-induced intestinal microbiota dysbiosis. At first, we needed to optimize the isolation and quantify DNA copy numbers using standard curves to perform by qPCR this interspecies comparison. Using this approach, we determined that total microflora was similar in control rats and mice and was mainly composed of Firmicutes and Bacteroidetes at a ratio of 10/1. Ferric juvenile administration did not modify the microflora profile in control animals. Total microflora numbers remained unchanged whichever experimental conditions studied. Following TNBS-induced colitis, the Firmicutes/Bacteroidetes ratio was altered resulting in a decrease of the Firmicutes numbers and an increase of the Bacteroidetes numbers typical of a gut inflammatory reaction. In parallel, the subdominant population, the enterobacteria was also increased. However, ferric iron supplementation for the juvenile period prevented the increase of Bacteroidetes and of enterobacteria numbers consecutive to the colitis in both the studied species at adulthood.CONCLUSION: Rats and mice juvenile chronic ferric iron ingestion prevents colitis and dysbiosis at adulthood as assessed by the first interspecies comparison.展开更多
Cobblestone, glass beads and active carbon were selected as bacterial supports to study immobilization of Acidithiobacillus ferrooxidans in packed bed reactors. The production of ferric iron was then investigated in t...Cobblestone, glass beads and active carbon were selected as bacterial supports to study immobilization of Acidithiobacillus ferrooxidans in packed bed reactors. The production of ferric iron was then investigated in these immobilized reactors in batch and continuous operation modes. The results show that stable biofilm forms in cobblestone and active carbon supports, thus these two kinds of supports are suitable for immobilization of A. ferrooxidans. In batch culture, ferric iron productivity in reactor with cobblestone as supports is 0.61 g/(L·h), which is 1.49 times higher than that in suspended culture reactor. In continuous operation mode, the maximum ferric iron productivity in reactor with cobblestone as supports is 1.54 g/(L·h), which is 3.76 times higher than that in suspended culture reactor. The maximum ferric iron productivity in reactor with active carbon as supports is 1.89 g/(L·h), which is 4.61 times higher than that in suspended culture reactor. In addition to bacteria, the results of X-ray diffraction and scanning electronic microscope analysis show that there is a lot of exopolysaccharide, jarosite and ammoniojarosite in biofilm, which plays important role in the formation of biofilm.展开更多
It is well known that in pyroxene structure, there are two metal sites, M1 and M2.Generally speaking, ferrous iron in each of these sites would normally be expected to give rise to a doublet. However, anomies have bee...It is well known that in pyroxene structure, there are two metal sites, M1 and M2.Generally speaking, ferrous iron in each of these sites would normally be expected to give rise to a doublet. However, anomies have been found in the relative areas of the peaks in the room temperature spectra of some clinopyroxene (CPX) when the above assigninent is folowed. Ac-cording to the calculation of Next Nearest Neighbor configurations of divalent cations in M1,we found that the four configurations of M1 can be divided into two groups. One group is 3Ca configuration that increases with the content of Ca (p. f. u); the other group is made up of three No-3Ca configurations that decrease with the content of Ca. The two groups contribute to the spectrum structure of M1, so in this study we fit two doublets for ferrous iron in M1.Though there were severa reports on Fe3+ in tetrahedral site previously, it wa not sure that Fe3+ occupies the T site is a universal fact in CPX, despite of the content of A1. We found that the Fe3+ in the T site fitted by Medauer spectroscopy is negatively correlated to the Si content in the T site and positively correlated to the Fe3 + in the T site estimated on the suppo-sition that Fe3+ and Al occupy the T site randomly. If it is true, it is important in the model-ing of ion exchange geobarometries and gepthermornetries.展开更多
Understanding the mechanism of oxidative stress is likely to yield new insights regarding the pathogenesis of Alzheimer’s disease (AD). Our earlier work focused on the difference between hemoglobin and methemoglobin ...Understanding the mechanism of oxidative stress is likely to yield new insights regarding the pathogenesis of Alzheimer’s disease (AD). Our earlier work focused on the difference between hemoglobin and methemoglobin degradation, respectively leading to ferrous (Fe2+) iron, or ferric (Fe3+) iron. Methemoglobin has the role of carrier, the donor of cytotoxic and redox-active ferric (Fe3+) iron, which can directly accumulate and increase the rate of capillary endothelial cell apoptosis, and may cross into the brain parenchyma, to the astrocytes, glia, neurons, and other neuronal cells (neurovascular unit). This supposition helps us to understand the transport and neuronal accumulation process of ferric iron, and determine how iron is transported and accumulated intracellularly, identifiable as “Brain rust”. Earlier research found that the incidences of neonatal jaundice (p = 0.034), heart murmur (p = 0.011) and disorders such as dyslalia and learning/memory impairments (p = 0.002) were significantly higher in those children born from mothers with methemoglobinemia. Our hypothesis suggests that prenatal iron abnormalities could lead to greater neuronal death, the disease ageing process, and neurodegenerative disorders such as AD and other neurodegenerative diseases.展开更多
A robust voltammetric method has been developed and validated for the determination of Fe（Ⅱ） and Fe（Ⅲ） in pharmaceutical iron polysaccharidic complexes. Undesirable low molecular weight iron complexes, at concen...A robust voltammetric method has been developed and validated for the determination of Fe（Ⅱ） and Fe（Ⅲ） in pharmaceutical iron polysaccharidic complexes. Undesirable low molecular weight iron complexes, at concentration about 3% in the pharmaceutical formulation, can be easily determined with good accuracy and precision. This methodology can be proposed as a viable, environmentally sustainable substitute for the conventional Normal Pulse Polarographic method in US Pharmacopeia, with better analytical figures of merit, and reduced Hg consumption. A deeper insight in Fe（Ⅱ） and Fe（Ⅲ） composition can be gained by the combined use of a new potentiometric technique after chemical decomposition of the complex.展开更多
The effects of ferrous and ferric iron as well as redox potential on copper and iron extraction from the copper flotation concentrate of Sarcheshmeh, Kerman, Iran, were evaluated using shake flask leaching examination...The effects of ferrous and ferric iron as well as redox potential on copper and iron extraction from the copper flotation concentrate of Sarcheshmeh, Kerman, Iran, were evaluated using shake flask leaching examinations. Experiments were carried out in the presence and absence of a mixed culture of moderately thermophile microorganisms at 50?C. Chemical leaching experiments were performed in the absence and presence of 0.15 M iron (ferric added medium, ferrous added medium and a mixture medium regulated at 420 mV, Pt. vs. Ag/AgCl). In addition, bioleaching experiments were carried out in the presence and absence of 0.1 M iron (ferric and ferrous added mediua) at pulp density 10% (w/v), inoculated bacteria 20% (v/v), initial pH 1.6, nutrient medium Norris and yeast extract addition 0.02% (w/w). Abiotic leaching tests showed that the addition of iron at low solution redox potentials significantly increased the rate and extent of copper dissolution but when ferric iron was added, despite a higher initial rate of copper dissolution, leaching process stopped. Addition of both ferrous and ferric iron to the bioleaching medium levelled off the copper extraction and had an inhibitory effect which decreased the final redox potential. The monitoring of ferrous iron, ferric iron and copper extraction in leach solutions gave helpful results to understand the behaviour of iron cations during chemical and bacterial leaching processes.展开更多
<strong>Background:</strong><span style="font-family:;" "=""><span> Oral iron supplements, usually in the form of ferrous salts, are associated with gastric side effect...<strong>Background:</strong><span style="font-family:;" "=""><span> Oral iron supplements, usually in the form of ferrous salts, are associated with gastric side effects, poor compliance and failure of anemia treatment. To make iron more bioavailable, reduce the gastric side effects and increase the patient compliance, newer iron form, Ferric Sodium EDTA, has become available on the market. </span><b><span>Objective:</span></b><span> To assess the change in hemog</span><span>lobin level after iron supplementation with Ferric Sodium EDTA during </span><span>pregnancy. </span><b><span>Materials and Methods:</span></b><span> This is a longitudinal study concerning 337 </span><span>women attending antenatal care in maternity hospitals in the Democratic</span> <span>Republic of Congo from May to December 2020. The study included soci</span><span>odemographic and anthropometric variables along with type of feed, hemoglobin </span><span>level at recruitment and after three weeks of taking iron supplement with</span><span> Ferric Sodium EDTA (Hemoforce Plus Zinc</span></span><sup><span><span><sup></span><span>®</span><span></sup></span></span></sup><span style="font-family:;" "=""><span> syrup). For statistical analysis, we used t-test or ANOVA and chi-square test, the significance being stated at p < 0.05. </span><b><span>Results:</span></b><span> The frequency of pregnancy anemia was 51.4%. The mean </span><span>hemoglobin value of the overall study group was 8.7 ± 0.5 g/dL. The mean</span><span> maternal age and weight were 28.9 ± 6.2 years and 65.3 ± 11.7 kg, respectively. Most pregnant women (83.1%) had a diet consisting of food of plant and animal origin in equal proportions. Mean of Body Mass Index (BMI) was 24.6 ± 4.6 Kg/m</span><sup><span>2</span></sup><span> and 44.3% were overweight and obese. The co-morbidities associated were malaria and intestinal parasitosis found in 45% and 5.9% of cases, </span><span>respectively. After iron treatment with Ferric Sodium EDTA, the average</span><span> hemoglobin level increased to 11.2 g/dL with mean gain of 2.5 g/dL (p < 0.001). Pregnant women with excess weight (≥90 kg) and malaria as a comorbidity achieved a significantly lower mean hemoglobin gain (p = 0.014 and p = 0.022, respectively). Majority of women (91.2%) had not experienced the metallic taste of the syrup. </span><b><span>Conclusion:</span></b><span> Ferric Sodium EDTA as a novel iron formulation (Hemoforce Plus Zinc</span></span><sup><span><span><sup></span><span>®</span><span></sup></span></span></sup><span style="font-family:;" "=""><span>) has shown a rapid increase in hemoglobin levels in pregnant women suffering from anemia. The speedy rise in hemoglobin is related to the property of Ferric Sodium EDTA to enhance the iron absorption by inhibiting the dietary iron inhibitors. Thus, Ferric Sodium </span><span>EDTA should be used as an effective and promising iron supplement in</span><span> pregnant women with iron deficiency anemia.</span></span>展开更多
Micaceous iron oxide(MIO) with a hexagonal flaky shape was prepared by hydrothermal method.The ferric hydroxide used as precursor was obtained by an acidic leaching solution of pyrite cinders reacting with ammonia sol...Micaceous iron oxide(MIO) with a hexagonal flaky shape was prepared by hydrothermal method.The ferric hydroxide used as precursor was obtained by an acidic leaching solution of pyrite cinders reacting with ammonia solution.The optimal experimental conditions for preparing micaceous iron oxide were investigated by orthogonal experiments.Micaceous iron oxide can be successfully prepared when optimal parameters of total iron concentration of 2.0 mol/L,pH value of 8,n(Fe2+)/n(Fe3+) of 0.1,mass of seed crystal of 1 g,reaction temperature of 260 °C and reaction time of 30 min are applied.X-ray diffractometry(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM) and selected area electron diffractometry(SAEM) were adopted to characterize the hydrothermal products prepared under optimal conditions.The results indicate that highly crystallized α-Fe2O3 hexagonal flakes,about 1.0-1.5 μm in diameter and 0.1 μm in thickness,are prepared.Furthermore,the quality of micaceous iron oxide prepared can meet the required characteristics of micaceous iron oxide pigments for paints(ISO10601-2007).展开更多
基金supported by the Special Fund for Agroscientific Research in the Public Interest,China(201103005)the Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences(2013–2017)
文摘Dissimilatory Fe（Ⅲ） reduction is an important process in the geochemical cycle of iron in anoxic environment. As the main products of dissimilatory iron reduction, the Fe（Ⅱ） species accumulation could indicate the reduction ability. The effects of different green manures on Fe（Ⅲ） reduction in paddy soil were explored based on a 31-year rice-rice-winter green manure cropping experiment. Four treatments were involved, i.e., rice-rice-milk vetch （RRV）, rice-rice-rape （RRP）, rice-rice-ryegrass （RRG） and rice-rice-winter fallow （RRF）. Soils were sampled at flowering stage of milk vetch and rape （S1）, before transplantation （S2）, at tillering （S3）, jointing （S4）, and mature （S5） stages of the early rice, and after the harvest of the late rice （S6）. The contents of TFeHa （HCI-extractable total Fe）, Fe（Ⅱ）HCI （HCI-extractable Fe（Ⅱ） species） and Fe（Ⅲ）HCI （HCI- extractable Fe（Ⅲ） species） were measured. The correlations among those Fe species with selected soil environmental factors and the dynamic characteristics of Fe（Ⅱ）HCI accumulation were investigated. The results showed that TFeHc~ in RRF was significantly higher than those in the green manure treatments at most of the sampling stages. Fe（II）Ha increased rapidly after the incorporation of green manures in all treatments and kept rising with the growth of early rice. Fe（Ⅱ）Ha in RRG was quite different from those in other treatments, i.e., it reached the highest at the S2 stage, then increased slowly and became the lowest one at the S4 and S5 stages. Fe（Ⅲ）Ha showed oppositely, and Fe（Ⅱ）HCI/Fe（Ⅲ）HCI performed similarly to Fe（Ⅱ）HCI The maximum accumulation potential of Fe（Ⅱ）HCI was significantly higher in RRF, while the highest maximum reaction rate of Fe（Ⅱ）Ha accumulation appeared in RRG. Significant correlations were found between the indexes of Fe（Ⅱ）HCI accumulation and soil pH, oxidation-reduction potential （Eh） and total organic acids, respectively. In together, we found that long-term application of green manures decreased the TFeHa in red paddy soils, but promoted the ability of Fe（lll） reduction, especially the ryegrass; Fe（Ⅱ）Ha increased along with the growth of rice and was affected by soil conditions and environmental factors, especially the water and redox ability.
基金Supported by Institut Polytechnique LaSalle Beauvais
文摘AIM: To assess whether juvenile chronic ferric iron ingestion limit colitis and dysbiosis at adulthood in rats and mice. METHODS: Two sets of experiments were designed. In the first set, recently weaned mice were either orally administered ferrous (Fe2+) iron salt or ferric (Fe3+) microencapsulated iron for 6 wk. The last week of experiments trinitrobenzene sulfonic acid (TNBS) colitis was induced. In the second set, juvenile rats received the microencapsulated ferric iron for 6 wk and were also submitted to TNBS colitis during the last week of experiments. In both sets of experiments, animals were sacrificed 7 d after TNBS instillation. Severity of the inflammation was assessed by scoring macroscopic lesions and quantifying colonic myeloperoxidase (MPO) activity. Alteration of the microflora profile was estimated usingquantitative polymerase chain reaction (qPCR) by measuring the evolution of total caecal microflora, Bacteroidetes, Firmicutes and enterobacteria. RESULTS: Neither ferrous nor ferric iron daily exposures at the juvenile period result in any effect in control animals at adulthood although ferrous iron repeated administration in infancy limited weight gain. Ferrous iron was unable to limit the experimental colitis (1.71 ± 0.27 MPO U/mg proteinvs 2.47 ± 0.22 MPO U/mg protein in colitic mice). In contrast, ferric iron significantly prevented the increase of MPO activity (1.64 ± 0.14 MPO U/mg protein) in TNBS-induced colitis. Moreover, this positive effect was observed at both the doses of ferric iron used (75 and 150 mg/kg per day po - 6 wk). In the study we also compared, in both rats and mice, the consequences of chronic repeated low level exposure to ferric iron (75 mg/kg per day po - 6 wk) on TNBS-induced colitis and its related dysbiosis. We confirmed that ferric iron limited the TNBS-induced increase of MPO activity in both the rodent species. Furthermore, we assessed the ferric iron incidence on TNBS-induced intestinal microbiota dysbiosis. At first, we needed to optimize the isolation and quantify DNA copy numbers using standard curves to perform by qPCR this interspecies comparison. Using this approach, we determined that total microflora was similar in control rats and mice and was mainly composed of Firmicutes and Bacteroidetes at a ratio of 10/1. Ferric juvenile administration did not modify the microflora profile in control animals. Total microflora numbers remained unchanged whichever experimental conditions studied. Following TNBS-induced colitis, the Firmicutes/Bacteroidetes ratio was altered resulting in a decrease of the Firmicutes numbers and an increase of the Bacteroidetes numbers typical of a gut inflammatory reaction. In parallel, the subdominant population, the enterobacteria was also increased. However, ferric iron supplementation for the juvenile period prevented the increase of Bacteroidetes and of enterobacteria numbers consecutive to the colitis in both the studied species at adulthood.CONCLUSION: Rats and mice juvenile chronic ferric iron ingestion prevents colitis and dysbiosis at adulthood as assessed by the first interspecies comparison.
基金Project(50321402) supported by the National Natural Science Foundation of China Project(2004CB619204) supported by the National Basic Research Program of China Project(DY105-02-04-05) supported by the China Ocean Mineral Resources R&D Association
文摘Cobblestone, glass beads and active carbon were selected as bacterial supports to study immobilization of Acidithiobacillus ferrooxidans in packed bed reactors. The production of ferric iron was then investigated in these immobilized reactors in batch and continuous operation modes. The results show that stable biofilm forms in cobblestone and active carbon supports, thus these two kinds of supports are suitable for immobilization of A. ferrooxidans. In batch culture, ferric iron productivity in reactor with cobblestone as supports is 0.61 g/(L·h), which is 1.49 times higher than that in suspended culture reactor. In continuous operation mode, the maximum ferric iron productivity in reactor with cobblestone as supports is 1.54 g/(L·h), which is 3.76 times higher than that in suspended culture reactor. The maximum ferric iron productivity in reactor with active carbon as supports is 1.89 g/(L·h), which is 4.61 times higher than that in suspended culture reactor. In addition to bacteria, the results of X-ray diffraction and scanning electronic microscope analysis show that there is a lot of exopolysaccharide, jarosite and ammoniojarosite in biofilm, which plays important role in the formation of biofilm.
文摘It is well known that in pyroxene structure, there are two metal sites, M1 and M2.Generally speaking, ferrous iron in each of these sites would normally be expected to give rise to a doublet. However, anomies have been found in the relative areas of the peaks in the room temperature spectra of some clinopyroxene (CPX) when the above assigninent is folowed. Ac-cording to the calculation of Next Nearest Neighbor configurations of divalent cations in M1,we found that the four configurations of M1 can be divided into two groups. One group is 3Ca configuration that increases with the content of Ca (p. f. u); the other group is made up of three No-3Ca configurations that decrease with the content of Ca. The two groups contribute to the spectrum structure of M1, so in this study we fit two doublets for ferrous iron in M1.Though there were severa reports on Fe3+ in tetrahedral site previously, it wa not sure that Fe3+ occupies the T site is a universal fact in CPX, despite of the content of A1. We found that the Fe3+ in the T site fitted by Medauer spectroscopy is negatively correlated to the Si content in the T site and positively correlated to the Fe3 + in the T site estimated on the suppo-sition that Fe3+ and Al occupy the T site randomly. If it is true, it is important in the model-ing of ion exchange geobarometries and gepthermornetries.
文摘Understanding the mechanism of oxidative stress is likely to yield new insights regarding the pathogenesis of Alzheimer’s disease (AD). Our earlier work focused on the difference between hemoglobin and methemoglobin degradation, respectively leading to ferrous (Fe2+) iron, or ferric (Fe3+) iron. Methemoglobin has the role of carrier, the donor of cytotoxic and redox-active ferric (Fe3+) iron, which can directly accumulate and increase the rate of capillary endothelial cell apoptosis, and may cross into the brain parenchyma, to the astrocytes, glia, neurons, and other neuronal cells (neurovascular unit). This supposition helps us to understand the transport and neuronal accumulation process of ferric iron, and determine how iron is transported and accumulated intracellularly, identifiable as “Brain rust”. Earlier research found that the incidences of neonatal jaundice (p = 0.034), heart murmur (p = 0.011) and disorders such as dyslalia and learning/memory impairments (p = 0.002) were significantly higher in those children born from mothers with methemoglobinemia. Our hypothesis suggests that prenatal iron abnormalities could lead to greater neuronal death, the disease ageing process, and neurodegenerative disorders such as AD and other neurodegenerative diseases.
基金supported by FAR, Fondo Ateneoper la Ricerca Universitá di Pavia,Italy
文摘A robust voltammetric method has been developed and validated for the determination of Fe（Ⅱ） and Fe（Ⅲ） in pharmaceutical iron polysaccharidic complexes. Undesirable low molecular weight iron complexes, at concentration about 3% in the pharmaceutical formulation, can be easily determined with good accuracy and precision. This methodology can be proposed as a viable, environmentally sustainable substitute for the conventional Normal Pulse Polarographic method in US Pharmacopeia, with better analytical figures of merit, and reduced Hg consumption. A deeper insight in Fe（Ⅱ） and Fe（Ⅲ） composition can be gained by the combined use of a new potentiometric technique after chemical decomposition of the complex.
文摘The effects of ferrous and ferric iron as well as redox potential on copper and iron extraction from the copper flotation concentrate of Sarcheshmeh, Kerman, Iran, were evaluated using shake flask leaching examinations. Experiments were carried out in the presence and absence of a mixed culture of moderately thermophile microorganisms at 50?C. Chemical leaching experiments were performed in the absence and presence of 0.15 M iron (ferric added medium, ferrous added medium and a mixture medium regulated at 420 mV, Pt. vs. Ag/AgCl). In addition, bioleaching experiments were carried out in the presence and absence of 0.1 M iron (ferric and ferrous added mediua) at pulp density 10% (w/v), inoculated bacteria 20% (v/v), initial pH 1.6, nutrient medium Norris and yeast extract addition 0.02% (w/w). Abiotic leaching tests showed that the addition of iron at low solution redox potentials significantly increased the rate and extent of copper dissolution but when ferric iron was added, despite a higher initial rate of copper dissolution, leaching process stopped. Addition of both ferrous and ferric iron to the bioleaching medium levelled off the copper extraction and had an inhibitory effect which decreased the final redox potential. The monitoring of ferrous iron, ferric iron and copper extraction in leach solutions gave helpful results to understand the behaviour of iron cations during chemical and bacterial leaching processes.
文摘<strong>Background:</strong><span style="font-family:;" "=""><span> Oral iron supplements, usually in the form of ferrous salts, are associated with gastric side effects, poor compliance and failure of anemia treatment. To make iron more bioavailable, reduce the gastric side effects and increase the patient compliance, newer iron form, Ferric Sodium EDTA, has become available on the market. </span><b><span>Objective:</span></b><span> To assess the change in hemog</span><span>lobin level after iron supplementation with Ferric Sodium EDTA during </span><span>pregnancy. </span><b><span>Materials and Methods:</span></b><span> This is a longitudinal study concerning 337 </span><span>women attending antenatal care in maternity hospitals in the Democratic</span> <span>Republic of Congo from May to December 2020. The study included soci</span><span>odemographic and anthropometric variables along with type of feed, hemoglobin </span><span>level at recruitment and after three weeks of taking iron supplement with</span><span> Ferric Sodium EDTA (Hemoforce Plus Zinc</span></span><sup><span><span><sup></span><span>®</span><span></sup></span></span></sup><span style="font-family:;" "=""><span> syrup). For statistical analysis, we used t-test or ANOVA and chi-square test, the significance being stated at p < 0.05. </span><b><span>Results:</span></b><span> The frequency of pregnancy anemia was 51.4%. The mean </span><span>hemoglobin value of the overall study group was 8.7 ± 0.5 g/dL. The mean</span><span> maternal age and weight were 28.9 ± 6.2 years and 65.3 ± 11.7 kg, respectively. Most pregnant women (83.1%) had a diet consisting of food of plant and animal origin in equal proportions. Mean of Body Mass Index (BMI) was 24.6 ± 4.6 Kg/m</span><sup><span>2</span></sup><span> and 44.3% were overweight and obese. The co-morbidities associated were malaria and intestinal parasitosis found in 45% and 5.9% of cases, </span><span>respectively. After iron treatment with Ferric Sodium EDTA, the average</span><span> hemoglobin level increased to 11.2 g/dL with mean gain of 2.5 g/dL (p < 0.001). Pregnant women with excess weight (≥90 kg) and malaria as a comorbidity achieved a significantly lower mean hemoglobin gain (p = 0.014 and p = 0.022, respectively). Majority of women (91.2%) had not experienced the metallic taste of the syrup. </span><b><span>Conclusion:</span></b><span> Ferric Sodium EDTA as a novel iron formulation (Hemoforce Plus Zinc</span></span><sup><span><span><sup></span><span>®</span><span></sup></span></span></sup><span style="font-family:;" "=""><span>) has shown a rapid increase in hemoglobin levels in pregnant women suffering from anemia. The speedy rise in hemoglobin is related to the property of Ferric Sodium EDTA to enhance the iron absorption by inhibiting the dietary iron inhibitors. Thus, Ferric Sodium </span><span>EDTA should be used as an effective and promising iron supplement in</span><span> pregnant women with iron deficiency anemia.</span></span>
基金Project(2008A090300016) supported by Major Science & Technology Special Program of Guangdong Province,China
文摘Micaceous iron oxide(MIO) with a hexagonal flaky shape was prepared by hydrothermal method.The ferric hydroxide used as precursor was obtained by an acidic leaching solution of pyrite cinders reacting with ammonia solution.The optimal experimental conditions for preparing micaceous iron oxide were investigated by orthogonal experiments.Micaceous iron oxide can be successfully prepared when optimal parameters of total iron concentration of 2.0 mol/L,pH value of 8,n(Fe2+)/n(Fe3+) of 0.1,mass of seed crystal of 1 g,reaction temperature of 260 °C and reaction time of 30 min are applied.X-ray diffractometry(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM) and selected area electron diffractometry(SAEM) were adopted to characterize the hydrothermal products prepared under optimal conditions.The results indicate that highly crystallized α-Fe2O3 hexagonal flakes,about 1.0-1.5 μm in diameter and 0.1 μm in thickness,are prepared.Furthermore,the quality of micaceous iron oxide prepared can meet the required characteristics of micaceous iron oxide pigments for paints(ISO10601-2007).
