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Sample records for iron metabolism study

  1. Use of radionuclides in the study of iron metabolism in iron deficient states

    International Nuclear Information System (INIS)

    Anatkov, A.; Karakostov, K.; Iliev, Z.; Dimitrov, L.

    1977-01-01

    A study of erythropoiesis in iron deficient anemias by simultaneous labelling with the radionuclides iron 59 and chromium 51 revealed accelerated iron circuit, higher percentage of daily hemolysis, severely reduced or even absent labile reserves, decreased volume of packed red cells with no decrease of blood volume. Adequate iron 59 utilization was observed after administration of large doses of iron (500 mg) in the treatment of iron deficient anemias. (author)

  2. Iron metabolism in critically ill patients developing anemia of inflammation: a case control study.

    Science.gov (United States)

    Boshuizen, Margit; Binnekade, Jan M; Nota, Benjamin; van de Groep, Kirsten; Cremer, Olaf L; Tuinman, Pieter R; Horn, Janneke; Schultz, Marcus J; van Bruggen, Robin; Juffermans, Nicole P

    2018-05-02

    Anemia occurring as a result of inflammatory processes (anemia of inflammation, AI) has a high prevalence in critically ill patients. Knowledge on changes in iron metabolism during the course of AI is limited, hampering the development of strategies to counteract AI. This case control study aimed to investigate iron metabolism during the development of AI in critically ill patients. Iron metabolism in 30 patients who developed AI during ICU stay was compared with 30 septic patients with a high Hb and 30 non-septic patients with a high Hb. Patients were matched on age and sex. Longitudinally collected plasma samples were analyzed for levels of parameters of iron metabolism. A linear mixed model was used to assess the predictive values of the parameters. In patients with AI, levels of iron, transferrin and transferrin saturation showed an early decrease compared to controls with a high Hb, already prior to the development of anemia. Ferritin, hepcidin and IL-6 levels were increased in AI compared to controls. During AI development, erythroferrone decreased. Differences in iron metabolism between groups were not influenced by APACHE IV score. The results show that in critically ill patients with AI, iron metabolism is already altered prior to the development of anemia. Levels of iron regulators in AI differ from septic controls with a high Hb, irrespective of disease severity. AI is characterized by high levels of hepcidin, ferritin and IL-6 and low levels of iron, transferrin and erythroferrone.

  3. Studying disorders of vertebrate iron and heme metabolism using zebrafish.

    Science.gov (United States)

    van der Vorm, Lisa N; Paw, Barry H

    2017-01-01

    Iron is a crucial component of heme- and iron-sulfur clusters, involved in vital cellular functions such as oxygen transport, DNA synthesis, and respiration. Both excess and insufficient levels of iron and heme-precursors cause human disease, such as iron-deficiency anemia, hemochromatosis, and porphyrias. Hence, their levels must be tightly regulated, requiring a complex network of transporters and feedback mechanisms. The use of zebrafish to study these pathways and the underlying genetics offers many advantages, among others their optical transparency, ex-vivo development and high genetic and physiological conservations. This chapter first reviews well-established methods, such as large-scale mutagenesis screens that have led to the initial identification of a series of iron and heme transporters and the generation of a variety of mutant lines. Other widely used techniques are based on injection of RNA, including complementary morpholino knockdown and gene overexpression. In addition, we highlight several recently developed approaches, most notably endonuclease-based gene knockouts such as TALENs or the CRISPR/Cas9 system that have been used to study how loss of function can induce human disease phenocopies in zebrafish. Rescue by chemical complementation with iron-based compounds or small molecules can subsequently be used to confirm causality of the genetic defect for the observed phenotype. All together, zebrafish have proven to be - and will continue to serve as an ideal model to advance our understanding of the pathogenesis of human iron and heme-related diseases and to develop novel therapies to treat these conditions. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Advantages and disadvantages of the animal models v. in vitro studies in iron metabolism: a review.

    Science.gov (United States)

    García, Y; Díaz-Castro, J

    2013-10-01

    Iron deficiency is the most common nutritional deficiency in the world. Special molecules have evolved for iron acquisition, transport and storage in soluble, nontoxic forms. Studies about the effects of iron on health are focused on iron metabolism or nutrition to prevent or treat iron deficiency and anemia. These studies are focused in two main aspects: (1) basic studies to elucidate iron metabolism and (2) nutritional studies to evaluate the efficacy of iron supplementation to prevent or treat iron deficiency and anemia. This paper reviews the advantages and disadvantages of the experimental models commonly used as well as the methods that are more used in studies related to iron. In vitro studies have used different parts of the gut. In vivo studies are done in humans and animals such as mice, rats, pigs and monkeys. Iron metabolism is a complex process that includes interactions at the systemic level. In vitro studies, despite physiological differences to humans, are useful to increase knowledge related to this essential micronutrient. Isotopic techniques are the most recommended in studies related to iron, but their high cost and required logistic, making them difficult to use. The depletion-repletion of hemoglobin is a method commonly used in animal studies. Three depletion-repletion techniques are mostly used: hemoglobin regeneration efficiency, relative biological values (RBV) and metabolic balance, which are official methods of the association of official analytical chemists. These techniques are well-validated to be used as studies related to iron and their results can be extrapolated to humans. Knowledge about the main advantages and disadvantages of the in vitro and animal models, and methods used in these studies, could increase confidence of researchers in the experimental results with less costs.

  5. In vivo iron metabolism by IRMS

    Science.gov (United States)

    Iron isotopes are used in both biological and geological investigations. Three low-abundance stable isotopes are available for human studies. They have been widely used to study iron metabolism. They have provided valuable insights into iron deficiency, one of the most common micronutrient deficienc...

  6. Iron metabolism and toxicity

    International Nuclear Information System (INIS)

    Papanikolaou, G.; Pantopoulos, K.

    2005-01-01

    Iron is an essential nutrient with limited bioavailability. When present in excess, iron poses a threat to cells and tissues, and therefore iron homeostasis has to be tightly controlled. Iron's toxicity is largely based on its ability to catalyze the generation of radicals, which attack and damage cellular macromolecules and promote cell death and tissue injury. This is lucidly illustrated in diseases of iron overload, such as hereditary hemochromatosis or transfusional siderosis, where excessive iron accumulation results in tissue damage and organ failure. Pathological iron accumulation in the liver has also been linked to the development of hepatocellular cancer. Here we provide a background on the biology and toxicity of iron and the basic concepts of iron homeostasis at the cellular and systemic level. In addition, we provide an overview of the various disorders of iron overload, which are directly linked to iron's toxicity. Finally, we discuss the potential role of iron in malignant transformation and cancer

  7. Isotope pattern deconvolution as a tool to study iron metabolism in plants.

    Science.gov (United States)

    Rodríguez-Castrillón, José Angel; Moldovan, Mariella; García Alonso, J Ignacio; Lucena, Juan José; García-Tomé, Maria Luisa; Hernández-Apaolaza, Lourdes

    2008-01-01

    Isotope pattern deconvolution is a mathematical technique for isolating distinct isotope signatures from mixtures of natural abundance and enriched tracers. In iron metabolism studies measurement of all four isotopes of the element by high-resolution multicollector or collision cell ICP-MS allows the determination of the tracer/tracee ratio with simultaneous internal mass bias correction and lower uncertainties. This technique was applied here for the first time to study iron uptake by cucumber plants using 57Fe-enriched iron chelates of the o,o and o,p isomers of ethylenediaminedi(o-hydroxyphenylacetic) acid (EDDHA) and ethylenediamine tetraacetic acid (EDTA). Samples of root, stem, leaves, and xylem sap, after exposure of the cucumber plants to the mentioned 57Fe chelates, were collected, dried, and digested using nitric acid. The isotopic composition of iron in the samples was measured by ICP-MS using a high-resolution multicollector instrument. Mass bias correction was computed using both a natural abundance iron standard and by internal correction using isotope pattern deconvolution. It was observed that, for plants with low 57Fe enrichment, isotope pattern deconvolution provided lower tracer/tracee ratio uncertainties than the traditional method applying external mass bias correction. The total amount of the element in the plants was determined by isotope dilution analysis, using a collision cell quadrupole ICP-MS instrument, after addition of 57Fe or natural abundance Fe in a known amount which depended on the isotopic composition of the sample.

  8. Isotope pattern deconvolution as a tool to study iron metabolism in plants

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez-Castrillon, Jose A.; Moldovan, Mariella; Garcia Alonso, J.I. [University of Oviedo, Department of Physical and Analytical Chemistry, Oviedo (Spain); Lucena, Juan J.; Garcia-Tome, Maria L.; Hernandez-Apaolaza, Lourdes [Autonoma University of Madrid, Department of Agricultural Chemistry, Madrid (Spain)

    2008-01-15

    Isotope pattern deconvolution is a mathematical technique for isolating distinct isotope signatures from mixtures of natural abundance and enriched tracers. In iron metabolism studies measurement of all four isotopes of the element by high-resolution multicollector or collision cell ICP-MS allows the determination of the tracer/tracee ratio with simultaneous internal mass bias correction and lower uncertainties. This technique was applied here for the first time to study iron uptake by cucumber plants using {sup 57}Fe-enriched iron chelates of the o,o and o,p isomers of ethylenediaminedi(o-hydroxyphenylacetic) acid (EDDHA) and ethylenediamine tetraacetic acid (EDTA). Samples of root, stem, leaves, and xylem sap, after exposure of the cucumber plants to the mentioned {sup 57}Fe chelates, were collected, dried, and digested using nitric acid. The isotopic composition of iron in the samples was measured by ICP-MS using a high-resolution multicollector instrument. Mass bias correction was computed using both a natural abundance iron standard and by internal correction using isotope pattern deconvolution. It was observed that, for plants with low {sup 57}Fe enrichment, isotope pattern deconvolution provided lower tracer/tracee ratio uncertainties than the traditional method applying external mass bias correction. The total amount of the element in the plants was determined by isotope dilution analysis, using a collision cell quadrupole ICP-MS instrument, after addition of {sup 57}Fe or natural abundance Fe in a known amount which depended on the isotopic composition of the sample. (orig.)

  9. Exploring the iron metabolism in multidrug resistant tuberculosis ...

    African Journals Online (AJOL)

    The iron metabolism plays a key role in the progression of active Tuberculosis. Several studies have shown a link between iron metabolism disorders an active tuberculosis. The aim of this study was to explore the iron metabolism of 100 patients with multidrug-resistant tuberculosis. (MDR-TB) treated with second ...

  10. Exploring the iron metabolism in multidrug resistant tuberculosis ...

    African Journals Online (AJOL)

    The iron metabolism plays a key role in the progression of active Tuberculosis. Several studies have shown a link between iron metabolism disorders an active tuberculosis. The aim of this study was to explore the iron metabolism of 100 patients with multidrug-resistant tuberculosis (MDR-TB) treated with second generation ...

  11. Genetic/metabolic effect of iron metabolism and rare anemias

    Directory of Open Access Journals (Sweden)

    Clara Camaschella

    2013-03-01

    Full Text Available Advances in iron metabolism have allowed a novel classification of iron disorders and to identify previously unknown diseases. These disorders include genetic iron overload (hemochromatosis and inherited iron-related anemias, in some cases accompanied by iron overload. Rare inherited anemias may affect the hepcidin pathway, iron absorption, transport, utilization and recycling. Among the genetic iron-related anemias the most common form is likely the iron-refractory iron-deficiency anemia (IRIDA, due to mutations of the hepcidin inhibitor TMPRSS6 encoding the serine protease matriptase-2. IRIDA is characterized by hepcidin up-regulation, decrease iron absorption and macrophage recycling and by microcytic- hypochromic anemia, unresponsive to oral iron. High serum hepcidin levels may suggest the diagnosis, which requires demonstrating the causal TMPRSS6 mutations by gene sequencing. Other rare microcytic hypochromic anemias associated with defects of iron transport-uptake are the rare hypotransferrinemia, and DMT1 and STEAP3 mutations. The degree of anemia is variable and accompanied by secondary iron overload even in the absence of blood transfusions. This is due to the iron-deficient or expanded erythropoiesis that inhibits hepcidin transcription, increases iron absorption, through the erythroid regulator, as in untransfused beta-thalassemia. Sideroblastic anemias are due to decreased mitochondrial iron utilization for heme or sulfur cluster synthesis. Their diagnosis requires demonstrating ringed sideroblasts by Perl’s staining of the bone marrow smears. The commonest X-linked form is due to deltaamino- levulinic-synthase-2-acid (ALAS2 mutations. The recessive, more severe form, affects SLC25A38, which encodes a potential mitochondrial importer of glycine, an amino acid essential for ALA synthesis and thus results in heme deficiency. Two disorders affect iron/sulfur cluster biogenesis: deficiency of the ATP-binding cassette B7 (ABCB7 causes X

  12. Use of radioisotopes in studying iron metabolism in humans in Sri Lanka

    International Nuclear Information System (INIS)

    Liyanage, C.E.; Thabrew, M.I.

    1994-01-01

    Anaemia due to iron deficiency is the commonest haematological problem found in Sri Lankan pregnant women and pre-school children. The reported prevalence rates amongst pregnant and lactating women ranged from 60-80%. The present study revealed that 3% of pregnant women had satisfactory iron stores and 57% had virtually no iron stores. Routine iron supplementation is justified not only to correct the anaemia but also to build up the maternal iron stores. In a longitudinal study of 100 pregnant women a very high prevalence was observed in spite of the fact that the population studied was on iron supplementation. A very poor compliance on iron therapy was seen. The incidence of low birth weight observed was 32%, quite similar to that has been reported previously for Sri Lanka. Therefore, further longitudinal studies have been designed to find out the efficacy of the present supplementary programme. In Galle District 54.5% of the pre-school children were found clearly anaemic and another 20% had evidence of iron depletion. As the dietary intake of iron was marginal, the weaning foods that are in practice were tested for iron availability. Iron absorption/availability studies by in-vivo (extrinsic tag method) and in-vitro (using radioiron 59 Fe tracer) methods have shown a very poor (less than 5%) availability in many of the commonly used weaning foods. A statistically significant decrease in iron availability was seen with increase in amount of polyphenols mainly in some of the preparations made with green leaves. Addition of ascorbic acid rich food items showed an increase in iron availability (by 2-6 times). Dietary zinc intake of 46 children (2-5 yrs) was found 2-4 mg/1000 kcal, relating to total energy intake. Mean plasma zinc concentration of these children was 13.8±0.8 μmol/L. Therefore further studies on the improvement of zinc and iron availability in weaning foods have been designed to be done in future. (author). 3 refs, 1 fig

  13. IDMS of FeO(OH) extracted from blood digests for studies of iron metabolism in humans

    International Nuclear Information System (INIS)

    Vieira, N.E.; Yergey

    1996-01-01

    The following isolation procedures were used for the determination of iron in water and digested whole blood matrices in connection with isotope dilution mass spectrometry (IDMS) of iron in blood for metabolic studies: precipitation as hydroxide, ion exchange chromatography using membrane filters, and evaporation of the untreated matrix followed by extraction of the residue with dilute acid. Although recovery is better with the cation exchange techniques, overall precision of IDMS analysis favours direct precipitation, which is also simpler and quicker. 3 refs., 3 tabs

  14. Radioisotope techniques in studies on the metabolism of calcium, iodine and iron in ruminants

    International Nuclear Information System (INIS)

    Lengemann, F.W.

    1984-01-01

    A short review is presented of radioisotopic procedures useful in research on calcium, iodine and iron studies with tropical ruminants. The procedures discussed can be useful in determining the availability of the mineral from feedstuffs, the faecal endogenous losses by the animal, detection of deficiency states, and responses to physiological and environmental stress. Methods that entail the use of radioisotopes in the laboratory or the use of stable isotopes in the animal are mentioned as alternatives to the administration of radioisotopes to the animal. While the review focuses on calcium, iodine and iron, the principles of the methods presented can be employed in the study of many other trace minerals. (author)

  15. Genome-wide association study identifies TF as a significant modifier gene of iron metabolism in HFE hemochromatosis.

    Science.gov (United States)

    de Tayrac, Marie; Roth, Marie-Paule; Jouanolle, Anne-Marie; Coppin, Hélène; le Gac, Gérald; Piperno, Alberto; Férec, Claude; Pelucchi, Sara; Scotet, Virginie; Bardou-Jacquet, Edouard; Ropert, Martine; Bouvet, Régis; Génin, Emmanuelle; Mosser, Jean; Deugnier, Yves

    2015-03-01

    Hereditary hemochromatosis (HH) is the most common form of genetic iron loading disease. It is mainly related to the homozygous C282Y/C282Y mutation in the HFE gene that is, however, a necessary but not a sufficient condition to develop clinical and even biochemical HH. This suggests that modifier genes are likely involved in the expressivity of the disease. Our aim was to identify such modifier genes. We performed a genome-wide association study (GWAS) using DNA collected from 474 unrelated C282Y homozygotes. Associations were examined for both quantitative iron burden indices and clinical outcomes with 534,213 single nucleotide polymorphisms (SNP) genotypes, with replication analyses in an independent sample of 748 C282Y homozygotes from four different European centres. One SNP met genome-wide statistical significance for association with transferrin concentration (rs3811647, GWAS p value of 7×10(-9) and replication p value of 5×10(-13)). This SNP, located within intron 11 of the TF gene, had a pleiotropic effect on serum iron (GWAS p value of 4.9×10(-6) and replication p value of 3.2×10(-6)). Both serum transferrin and iron levels were associated with serum ferritin levels, amount of iron removed and global clinical stage (pHFE-associated HH (HFE-HH) patients, identified the rs3811647 polymorphism in the TF gene as the only SNP significantly associated with iron metabolism through serum transferrin and iron levels. Because these two outcomes were clearly associated with the biochemical and clinical expression of the disease, an indirect link between the rs3811647 polymorphism and the phenotypic presentation of HFE-HH is likely. Copyright © 2014 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

  16. Mammalian iron metabolism and its control by iron regulatory proteins☆

    Science.gov (United States)

    Anderson, Cole P.; Shen, Lacy; Eisenstein, Richard S.; Leibold, Elizabeth A.

    2013-01-01

    Cellular iron homeostasis is maintained by iron regulatory proteins 1 and 2 (IRP1 and IRP2). IRPs bind to iron-responsive elements (IREs) located in the untranslated regions of mRNAs encoding protein involved in iron uptake, storage, utilization and export. Over the past decade, significant progress has been made in understanding how IRPs are regulated by iron-dependent and iron-independent mechanisms and the pathological consequences of IRP2 deficiency in mice. The identification of novel IREs involved in diverse cellular pathways has revealed that the IRP–IRE network extends to processes other than iron homeostasis. A mechanistic understanding of IRP regulation will likely yield important insights into the basis of disorders of iron metabolism. This article is part of a Special Issue entitled: Cell Biology of Metals. PMID:22610083

  17. Associations of iron metabolism genes with blood manganese levels: a population-based study with validation data from animal models

    Directory of Open Access Journals (Sweden)

    Claus Henn Birgit

    2011-11-01

    Full Text Available Abstract Background Given mounting evidence for adverse effects from excess manganese exposure, it is critical to understand host factors, such as genetics, that affect manganese metabolism. Methods Archived blood samples, collected from 332 Mexican women at delivery, were analyzed for manganese. We evaluated associations of manganese with functional variants in three candidate iron metabolism genes: HFE [hemochromatosis], TF [transferrin], and ALAD [δ-aminolevulinic acid dehydratase]. We used a knockout mouse model to parallel our significant results as a novel method of validating the observed associations between genotype and blood manganese in our epidemiologic data. Results Percentage of participants carrying at least one copy of HFE C282Y, HFE H63D, TF P570S, and ALAD K59N variant alleles was 2.4%, 17.7%, 20.1%, and 6.4%, respectively. Percentage carrying at least one copy of either C282Y or H63D allele in HFE gene was 19.6%. Geometric mean (geometric standard deviation manganese concentrations were 17.0 (1.5 μg/l. Women with any HFE variant allele had 12% lower blood manganese concentrations than women with no variant alleles (β = -0.12 [95% CI = -0.23 to -0.01]. TF and ALAD variants were not significant predictors of blood manganese. In animal models, Hfe-/- mice displayed a significant reduction in blood manganese compared with Hfe+/+ mice, replicating the altered manganese metabolism found in our human research. Conclusions Our study suggests that genetic variants in iron metabolism genes may contribute to variability in manganese exposure by affecting manganese absorption, distribution, or excretion. Genetic background may be critical to consider in studies that rely on environmental manganese measurements.

  18. Study on iron metabolism in children using double labelling of 51Cr and 59Fe

    International Nuclear Information System (INIS)

    Kobayashi, Masatsura

    1974-01-01

    In the children before and after treatment for iron deficiency anemia and those on ingesting a long-term low caloric and iron diet, life span of Ashby Technique 1/2(AST) red cells, circulatory blood volume (CBV), plasma iron disappearance(PID), red cell-iron utility(RCIU), plasma-iron turnover rate(PITR), and red cell-ironturnover rate(RCITR) were respectively determined using double labeling of 51 Cr and 59 Fe, and the following results and conclusions were obtained: In the patients with iron deficiency anemia, the rate of RCIU was highly increased, and simultaneously the shortening in AST was observed. Among the children with the iron deficiency anemia, five patients were examined immediately after the improvement on the anemia by iron drugs; the serum iron (SFe) averaged 74μg/ml. So the erthropiesis appeared to recover to normal, yet AST has hardly changed, still more has it shortened. In five children with celebral palsy associated with disturbance of physical development, who had ingested a long-term liquid low iron diet no evident increase of RCIU was found except for high calues of RCITR. The shortening in AST was not entirely seen in contrast with that of the simple alimentary iron deficiency anemia. Besides the CBV measured par kg of weight showed the remarkable increase. (Oyama, S.)

  19. The use of radioisotopes and low abundance stable isotopes for the study of bioavailability and the metabolism of iron, zinc and copper

    International Nuclear Information System (INIS)

    Aggett, P.J.; Fairweather Tait, S.

    1994-01-01

    The use of whole body counting and imaging with ''area of interest'' counting to monitor the metabolism of zinc in healthy volunteers and patients with coeliac diseases and cirrhosis is described as are studies of interaction between iron and copper. Stable isotopes of iron, copper and zinc have been used to investigate the metabolism of these elements in young infants and have proved useful in assessing the validity of current estimated requirements particularly of iron. Stable isotopes have also been used to improve the classic metabolic balance approach to the study of the homeostasis of zinc in zinc deprived volunteers, and have progressed to studies using plasma kinetic curves of the systemic compartmentation of zinc

  20. Divergence of iron metabolism in wild Malaysian yeast.

    Science.gov (United States)

    Lee, Hana N; Mostovoy, Yulia; Hsu, Tiffany Y; Chang, Amanda H; Brem, Rachel B

    2013-12-09

    Comparative genomic studies have reported widespread variation in levels of gene expression within and between species. Using these data to infer organism-level trait divergence has proven to be a key challenge in the field. We have used a wild Malaysian population of S. cerevisiae as a test bed in the search to predict and validate trait differences based on observations of regulatory variation. Malaysian yeast, when cultured in standard medium, activated regulatory programs that protect cells from the toxic effects of high iron. Malaysian yeast also showed a hyperactive regulatory response during culture in the presence of excess iron and had a unique growth defect in conditions of high iron. Molecular validation experiments pinpointed the iron metabolism factors AFT1, CCC1, and YAP5 as contributors to these molecular and cellular phenotypes; in genome-scale sequence analyses, a suite of iron toxicity response genes showed evidence for rapid protein evolution in Malaysian yeast. Our findings support a model in which iron metabolism has diverged in Malaysian yeast as a consequence of a change in selective pressure, with Malaysian alleles shifting the dynamic range of iron response to low-iron concentrations and weakening resistance to extreme iron toxicity. By dissecting the iron scarcity specialist behavior of Malaysian yeast, our work highlights the power of expression divergence as a signpost for biologically and evolutionarily relevant variation at the organismal level. Interpreting the phenotypic relevance of gene expression variation is one of the primary challenges of modern genomics.

  1. Interactions between iron and titanium metabolism in spinach: A chlorophyll fluorescence study in hydropony

    Czech Academy of Sciences Publication Activity Database

    Cígler, Petr; Olejníčková, Julie; Hrubý, Martin; Cséfalvay, Ladislav; Peterka, J.; Kužel, S.

    2010-01-01

    Roč. 167, č. 18 (2010), s. 1592-1597 ISSN 0176-1617 Institutional research plan: CEZ:AV0Z40550506; CEZ:AV0Z40500505; CEZ:AV0Z60870520 Keywords : chlorophyll fluorescence * iron * photosynthetic apparatus * spinach * titanium Subject RIV: CC - Organic Chemistry Impact factor: 2.677, year: 2010

  2. Staphylococcus aureus redirects central metabolism to increase iron availability.

    Directory of Open Access Journals (Sweden)

    David B Friedman

    2006-08-01

    Full Text Available Staphylococcus aureus pathogenesis is significantly influenced by the iron status of the host. However, the regulatory impact of host iron sources on S. aureus gene expression remains unknown. In this study, we combine multivariable difference gel electrophoresis and mass spectrometry with multivariate statistical analyses to systematically cluster cellular protein response across distinct iron-exposure conditions. Quadruplicate samples were simultaneously analyzed for alterations in protein abundance and/or post-translational modification state in response to environmental (iron chelation, hemin treatment or genetic (Deltafur alterations in bacterial iron exposure. We identified 120 proteins representing several coordinated biochemical pathways that are affected by changes in iron-exposure status. Highlighted in these experiments is the identification of the heme-regulated transport system (HrtAB, a novel transport system which plays a critical role in staphylococcal heme metabolism. Further, we show that regulated overproduction of acidic end-products brought on by iron starvation decreases local pH resulting in the release of iron from the host iron-sequestering protein transferrin. These findings reveal novel strategies used by S. aureus to acquire scarce nutrients in the hostile host environment and begin to define the iron and heme-dependent regulons of S. aureus.

  3. Modulation of intestinal sulfur assimilation metabolism regulates iron homeostasis

    Science.gov (United States)

    Hudson, Benjamin H.; Hale, Andrew T.; Irving, Ryan P.; Li, Shenglan; York, John D.

    2018-01-01

    Sulfur assimilation is an evolutionarily conserved pathway that plays an essential role in cellular and metabolic processes, including sulfation, amino acid biosynthesis, and organismal development. We report that loss of a key enzymatic component of the pathway, bisphosphate 3′-nucleotidase (Bpnt1), in mice, both whole animal and intestine-specific, leads to iron-deficiency anemia. Analysis of mutant enterocytes demonstrates that modulation of their substrate 3′-phosphoadenosine 5′-phosphate (PAP) influences levels of key iron homeostasis factors involved in dietary iron reduction, import and transport, that in part mimic those reported for the loss of hypoxic-induced transcription factor, HIF-2α. Our studies define a genetic basis for iron-deficiency anemia, a molecular approach for rescuing loss of nucleotidase function, and an unanticipated link between nucleotide hydrolysis in the sulfur assimilation pathway and iron homeostasis. PMID:29507250

  4. Iron absorption studies

    International Nuclear Information System (INIS)

    Ekenved, G.

    1976-01-01

    The main objective of the present work was to study iron absorption from different iron preparations in different types of subjects and under varying therapeutic conditions. The studies were performed with different radioiron isotope techniques and with a serum iron technique. The preparations used were solutions of ferrous sulphate and rapidly-disintegrating tablets containing ferrous sulphate, ferrous fumarate and ferrous carbonate and a slow-release ferrous sulphate tablet of an insoluble matrix type (Duroferon Durules). The serum iron method was evaluated and good correlation was found between the serum iron response and the total amount of iron absorbed after an oral dose of iron given in solution or in tablet form. New technique for studying the in-vivo release properties of tablets was presented. Iron tablets labelled with a radio-isotope were given to healthy subjects. The decline of the radioactivity in the tablets was followed by a profile scanning technique applied to different types of iron tablets. The release of iron from the two types of tablets was shown to be slower in vivo than in vitro. It was found that co-administration of antacids and iron tablets led to a marked reduction in the iron absorption and that these drugs should not be administered sumultaneously. A standardized meal markedly decreased the absorbability of iron from iron tablets. The influence of the meal was more marked with rapidly-disintegrating than with slow-release ferrous sulphate tablets. The absorption from rapidly-disintegrating and slow-release ferrous sulphate tablets was compared under practical clinical conditions during an extended treatment period. The studies were performed in healthy subjects, blood donors and patients with iron deficiency anaemia and it was found that the absorption of iron from the slow-release tablets was significantly better than from the rapidly-disintegrating tablets in all three groups of subjects. (author)

  5. Heme metabolism as an integral part of iron homeostasis

    Directory of Open Access Journals (Sweden)

    Paweł Lipiński

    2014-01-01

    Full Text Available Heme, a ferrous iron protoporphyrin IX complex, is employed as a prosthetic group in a number of diverse heme proteins that participate in important cellular and systemic physiological processes. Provision of an adequate amount of iron for heme biosynthesis is one of the elemental hallmarks of intracellular iron homeostasis. In the cell the bioavailability of iron for the two main iron biological pathways – heme synthesis and the biogenesis of iron-sulfur clusters ([Fe-S] – is mainly regulated by the IRP/IRE posttranscriptional system. The biogenesis of [Fe-S] centers is crucial for heme synthesis because these co-factors determine the activity of IRP1 and that of ferrochelatase, an enzyme responsible for the insertion of an iron into protoporphyrin IX to produce heme. On the other hand, delivery of iron for heme and hemoglobin synthesis in erythroblasts, precursors of erythrocytes in bone marrow, is an indispensable element of body iron homeostasis. This process relies on the recovery of iron from senescent red blood cells through the enzymatic degradation of heme molecules and recycling of iron to the circulation. Molecular coordination of these processes involves the activity of heme oxygenase 1, IRP1 and IRP2 as well as the functioning of the hepcidin-ferroportin regulatory axis. Recent studies show in mammals the existence of an expanded system of proteins involved in the transport of intact heme molecules at the cellular and systemic levels. The biological role of this system is of particular importance when the concentration of free heme reaches a toxic level in the body (intravascular hemolysis as well as locally in cells having intensive heme metabolism such as erythroblasts and macrophages.

  6. [Heme metabolism as an integral part of iron homeostasis].

    Science.gov (United States)

    Lipiński, Paweł; Starzyński, Rafał R; Styś, Agnieszka; Gajowiak, Anna; Staroń, Robert

    2014-01-02

    Heme, a ferrous iron protoporphyrin IX complex, is employed as a prosthetic group in a number of diverse heme proteins that participate in important cellular and systemic physiological processes. Provision of an adequate amount of iron for heme biosynthesis is one of the elemental hallmarks of intracellular iron homeostasis. In the cell the bioavailability of iron for the two main iron biological pathways--heme synthesis and the biogenesis of iron-sulfur clusters ([Fe-S])--is mainly regulated by the IRP/IRE posttranscriptional system. The biogenesis of [Fe-S] centers is crucial for heme synthesis because these co-factors determine the activity of IRP1 and that of ferrochelatase, an enzyme responsible for the insertion of an iron into protoporphyrin IX to produce heme. On the other hand, delivery of iron for heme and hemoglobin synthesis in erythroblasts, precursors of erythrocytes in bone marrow, is an indispensable element of body iron homeostasis. This process relies on the recovery of iron from senescent red blood cells through the enzymatic degradation of heme molecules and recycling of iron to the circulation. Molecular coordination of these processes involves the activity of heme oxygenase 1, IRP1 and IRP2 as well as the functioning of the hepcidin-ferroportin regulatory axis. Recent studies show in mammals the existence of an expanded system of proteins involved in the transport of intact heme molecules at the cellular and systemic levels. The biological role of this system is of particular importance when the concentration of free heme reaches a toxic level in the body (intravascular hemolysis) as well as locally in cells having intensive heme metabolism such as erythroblasts and macrophages.

  7. Blood lead levels, iron metabolism gene polymorphisms and homocysteine: a gene-environment interaction study.

    Science.gov (United States)

    Kim, Kyoung-Nam; Lee, Mee-Ri; Lim, Youn-Hee; Hong, Yun-Chul

    2017-12-01

    Homocysteine has been causally associated with various adverse health outcomes. Evidence supporting the relationship between lead and homocysteine levels has been accumulating, but most prior studies have not focused on the interaction with genetic polymorphisms. From a community-based prospective cohort, we analysed 386 participants (aged 41-71 years) with information regarding blood lead and plasma homocysteine levels. Blood lead levels were measured between 2001 and 2003, and plasma homocysteine levels were measured in 2007. Interactions of lead levels with 42 genotyped single-nucleotide polymorphisms (SNPs) in five genes ( TF , HFE , CBS , BHMT and MTR ) were assessed via a 2-degree of freedom (df) joint test and a 1-df interaction test. In secondary analyses using imputation, we further assessed 58 imputed SNPs in the TF and MTHFR genes. Blood lead concentrations were positively associated with plasma homocysteine levels (p=0.0276). Six SNPs in the TF and MTR genes were screened using the 2-df joint test, and among them, three SNPs in the TF gene showed interactions with lead with respect to homocysteine levels through the 1-df interaction test (plead levels. Blood lead levels were positively associated with plasma homocysteine levels measured 4-6 years later, and three SNPs in the TF gene modified the association. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  8. Effects of Protein-Iron Complex Concentrate Supplementation on Iron Metabolism, Oxidative and Immune Status in Preweaning Calves

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    Robert Kupczyński

    2017-07-01

    Full Text Available The objective of this study was to determine the effects of feeding protein-iron complex (PIC on productive performance and indicators of iron metabolism, hematology parameters, antioxidant and immune status during first 35 days of a calf’s life. Preparation of the complex involved enzymatic hydrolysis of milk casein (serine protease from Yarrowia lipolytica yeast. Iron chloride was then added to the hydrolyzate and lyophilizate. Calves were divided into treated groups: LFe (low iron dose 10 g/day calf of protein-iron complex, HFe (height iron dose 20 g/day calf, and control group. Dietary supplements containing the lower dose of concentrate had a significant positive effect on iron metabolism, while the higher dose of concentrate resulted in increase of total iron binding capacity (TIBC, saturation of transferrin and decrease of and unsaturated iron binding capacity (UIBC, which suggest iron overload. Additionally, treatment with the lower dose of iron remarkably increased the antioxidant parameters, mainly total antioxidant (TAS and glutathione peroxidase activity (GPx. Higher doses of PIC were related to lower total antioxidant status. IgG, IgM, insulin, glucose, TNFα and IGF-1 concentration did not change significantly in either group after supplementation. In practice, the use of protein-iron complex concentrate requires taking into account the iron content in milk replacers and other feedstuffs.

  9. Regulation of iron metabolism during Neisseria meningitidis infection in mice

    Energy Technology Data Exchange (ETDEWEB)

    Letendre, E.D.

    1984-01-01

    Bacterial invasion of vertebrates triggers a marked reduction in the levels of iron associated with the plasma transferrin (Tf) pool. This hypoferremic response has been regarded as a host attempt to withhold essential iron from the invading pathogen. The exact nature of the mechanisms involved remains obscure. The kinetics of iron processing by the RE system were studied by labeling the RE compartments with /sup 59/Fe-labeled denatured red blood cells. Uptake and redistribution of the label indicated the RE-processed iron was not returned to the plasma Tf pool during the hypoferremia. Fractionation of hepatic cellular compartments showed that this impaired release of iron resulted from a preferential incorporation of home-derived iron into the intracellular ferritin pool and this produces the hypoferremia. The role of ceruloplasmin (ferroxidase I,EC.1.16.3.1) (Cp) in iron metabolism during meningococcal infection was investigated. Plasma Cp ferroxidase activity was found to increase greatly in mice during the convalescence phase.

  10. Metabolism of manganese, iron, copper, and selenium in calves

    International Nuclear Information System (INIS)

    Ho, S.Y.

    1981-01-01

    Sixteen male Holstein calves were used to study manganese and iron metabolism. The calves were fed one of the following diets for 18 days: control, control + iron, control + manganese, and control + iron and manganese. All calves were dosed orally with manganese-54. Tissue concentrations of manganese, iron and manganese-54 were determined. Small intestinal iron was lower in calves fed the high manganese diet than in controls. Tissue manganese-54 was lower in calves fed a high manganese diet. Fecal manganese content increased in calves fed both high manganese and high manganese-high iron diets. Serum total iron was not affected by the dietary treatments. To study the effects of high dietary levels of copper and selenium on the intracellular distributions of these two elements in liver and kidney cytosol, calves were fed one of four diets for 15 days. These were 0 and 100 ppM supplemental copper and 0 and 1 ppM added selenium. The control diet containing 0.1 ppM of selenium and 15 ppM of copper. All calves were orally dosed 48 hrs prior to sacrifice with selenium-75. A high copper diet increased copper concentrations in all intracellular liver fractions and most kidney fractions. Only the effects in the liver were significant. Less copper was found in the mitochondria fractions in liver and kidney of calves fed a high selenium diet. Three major copper-binding protein peaks were separated from the soluble fractions of calf liver and kidney. Peak 1 appeared to be the major copper-binding protein in liver and kidney cytosol of copper-loaded animals. Added selenium alone or in combination with copper accentuated the copper accumulation in this peak. Most of selenium-75 was recovered in the same peak as the copper. The results of this experiment indicated that the large molecular proteins in liver and kidney cytosol of calves play an important role in copper and selenium-75 metabolism

  11. [Changes of iron metabolism indices in children with various genotypes of thalassema].

    Science.gov (United States)

    Huang, Yu-Jun; Wu, Shao-Guo; Ou, Xiao-Bing; Zhang, Li

    2010-02-01

    To study the value of iron metabolism indices, serum iron (SI), total iron blinding capacity (TIBC) and transferring (Tf), in thalassema. The serum samples from 9 children with silent alpha thalassema, 56 with standard alpha thalassema, 26 with HbH disease, 40 with beta+ thalassema, 56 with beta0 thalassema, 45 with iron deficiency anemia (IDA) and 70 healthy children were detected for SI, TIBC and Tf levels. The SI level increased (pcellule anaemia.

  12. Basic mechanisms of iron metabolism regulation and their clinical significance

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    L. M. Meshсheryakova

    2014-01-01

    Full Text Available This article is а composition of literature and experimental data of iron metabolism. There were studied the level of DMT-1, ferroportin, hepcidin at different stages of anemia and hemochromatosis. It is clear that the level of DMT-1 regulates by the hepcidin. Increaseing of the hepcidin concentration and decreasing DMT-1 level in patients with hemochromatosis explained good results of treatment.

  13. Basic mechanisms of iron metabolism regulation and their clinical significance

    Directory of Open Access Journals (Sweden)

    L. M. Meshсheryakova

    2015-01-01

    Full Text Available This article is а composition of literature and experimental data of iron metabolism. There were studied the level of DMT-1, ferroportin, hepcidin at different stages of anemia and hemochromatosis. It is clear that the level of DMT-1 regulates by the hepcidin. Increaseing of the hepcidin concentration and decreasing DMT-1 level in patients with hemochromatosis explained good results of treatment.

  14. The effect of interleukin-1 on iron metabolism in rats

    Energy Technology Data Exchange (ETDEWEB)

    Uchida, Tatsumi; Yamagiwa, Akio; Nakamura, Kenichi (The First Department of Internal Medicine, Fukushima Medical College, Fukushima (Japan))

    1991-01-01

    The effect of interleukin-1 on iron metabolism in rats was evaluated. Plasma iron decreased from 184 +- 16 {mu}g/dl (mean +- SE) to 24 +- 12 at 6 hours after interleukin-1 intramuscular administration in non-fasting rats and 109 +- 6 {mu}g/dl to 12 +- 1 {mu}g/dl in fasting rats, which was significantly lower than in control rats. Ferrokinetic studies showed a more rapid disapperance rate and lower iron turnover in interleukin-1-injected rats. The release of iron from the mononuclear phagocyte system to plasma was studied at 3 h after interleukin-1 administration. Although the percent of radioactivity in plasma of the total injected dose was 3.2 +- 0.6% in interleukin-1, which was significantly lower than in the control rats (5.4 +- 0.6%) at 9 h after intravenous injection of {sup 59}Fe chondroitin ferrous sulfate, there was no differnece between the amount of {sup 59}Fe released from the mononuclear phagocyte system over the first 9 h in interleukin-1 and control rats. These data appear to imply that iron release is unimpaired but that, for some reason, there is an enhanced rate of clearance of the {sup 59}Fe once it has been released from the mononuclear phagocyte system into the plasma. (author).

  15. Change in iron metabolism in rats after renal ischemia/reperfusion injury.

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    Guang-Liang Xie

    Full Text Available Previous studies have indicated that hepcidin, which can regulate iron efflux by binding to ferroportin-1 (FPN1 and inducing its internalization and degradation, acts as the critical factor in the regulation of iron metabolism. However, it is unknown whether hepcidin is involved in acute renal ischemia/reperfusion injury (IRI. In this study, an IRI rat model was established via right renal excision and blood interruption for 45 min in the left kidney, and iron metabolism indexes were examined to investigate the change in iron metabolism and to analyze the role of hepcidin during IRI. From 1 to 24 h after renal reperfusion, serum creatinine and blood urea nitrogen were found to be time-dependently increased with different degrees of kidney injury. Regular variations in iron metabolism indexes in the blood and kidneys were observed in renal IRI. Renal iron content, serum iron and serum ferritin increased early after reperfusion and then declined. Hepcidin expression in the liver significantly increased early after reperfusion, and its serum concentration increased beginning at 8 h after reperfusion. The splenic iron content decreased significantly in the early stage after reperfusion and then increased time-dependently with increasing reperfusion time, and the hepatic iron content showed a decrease in the early stage after reperfusion. The early decrease of the splenic iron content and hepatic iron content might indicate their contribution to the increase in serum iron in renal IRI. In addition, the duodenal iron content showed time-dependently decreased since 12 h after reperfusion in the IRI groups compared to the control group. Along with the spleen, the duodenum might contribute to the decrease in serum iron in the later stage after reperfusion. The changes in iron metabolism indexes observed in our study demonstrate an iron metabolism disorder in renal IRI, and hepcidin might be involved in maintaining iron homeostasis in renal IRI. These

  16. Altered erythropoiesis and iron metabolism in carriers of thalassemia

    Science.gov (United States)

    Guimarães, Jacqueline S.; Cominal, Juçara G.; Silva-Pinto, Ana Cristina; Olbina, Gordana; Ginzburg, Yelena Z.; Nandi, Vijay; Westerman, Mark; Rivella, Stefano; de Souza, Ana Maria

    2014-01-01

    The thalassemia syndromes (α- and β-thalassemia) are the most common and frequent disorders associated with ineffective erythropoiesis. Imbalance of α- or β-globin chain production results in impaired red blood cell synthesis, anemia and more erythroid progenitors in the blood stream. While patients affected by these disorders show definitive altered parameters related to erythropoiesis, the relationship between the degree of anemia, altered erythropoiesis and dysfunctional iron metabolism have not been investigated in both α-thalassemia carriers (ATC) and β-thalassemia carriers (BTC). Here we demonstrate that ATC have a significantly reduced hepcidin and increased soluble transferrin receptor levels but relatively normal hematological findings. In contrast, BTC have several hematological parameters significantly different from controls, including increased soluble transferrin receptor and erythropoietin levels. These changings in both groups suggest an altered balance between erythropoiesis and iron metabolism. The index sTfR/log ferrin and (hepcidin/ferritin)/sTfR are respectively increased and reduced relative to controls, proportional to the severity of each thalassemia group. In conclusion, we showed in this study, for the first time in the literature, that thalassemia carriers have altered iron metabolism and erythropoiesis. PMID:25307880

  17. Iron economy in Naegleria gruberi reflects its metabolic flexibility.

    Science.gov (United States)

    Mach, Jan; Bíla, Jarmila; Ženíšková, Kateřina; Arbon, Dominik; Malych, Ronald; Glavanakovová, Marie; Nývltová, Eva; Sutak, Robert

    2018-05-05

    Naegleria gruberi is a free-living amoeba, closely related to the human pathogen Naegleria fowleri, the causative agent of the deadly human disease primary amoebic meningoencephalitis. Herein, we investigated the effect of iron limitation on different aspects of N. gruberi metabolism. Iron metabolism is among the most conserved pathways found in all eukaryotes. It includes the delivery, storage and utilisation of iron in many cell processes. Nevertheless, most of the iron metabolism pathways of N. gruberi are still not characterised, even though iron balance within the cell is crucial. We found a single homolog of ferritin in the N. gruberi genome and showed its localisation in the mitochondrion. Using comparative mass spectrometry, we identified 229 upregulated and 184 down-regulated proteins under iron-limited conditions. The most down-regulated protein under iron-limited conditions was hemerythrin, and a similar effect on the expression of hemerythrin was found in N. fowleri. Among the other down-regulated proteins were [FeFe]-hydrogenase and its maturase HydG and several heme-containing proteins. The activities of [FeFe]-hydrogenase, as well as alcohol dehydrogenase, were also decreased by iron deficiency. Our results indicate that N. gruberi is able to rearrange its metabolism according to iron availability, prioritising mitochondrial pathways. We hypothesise that the mitochondrion is the center for iron homeostasis in N. gruberi, with mitochondrially localised ferritin as a potential key component of this process. Copyright © 2018 Australian Society for Parasitology. Published by Elsevier Ltd. All rights reserved.

  18. Ferrokinetic Parameters and Regulation of Iron Metabolism in Patients with Chronic Inflammatory Bowel Diseases

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    T.Y. Boiko

    2014-11-01

    Full Text Available Article presents parameters of iron metabolism and cytokines (IL-6 and TNF-α in patients with chronic inflammatory bowel diseases (CIBD. The material for the study was the blood of 69 patients with CIBD and anemia and 26 — without anemia. We have studied the features of main ferrokinetic parameters — iron, total iron-binding capacity of serum, transferrin saturation, ferritin, transferrin receptor, erythropoietin, hepcidin depending on hemoglobin level and the type of anemia. The relationship of iron metabolism disorders with the level of proinflammatory cytokines (IL-6 and TNF-α is shown.

  19. Co-regulation of Iron Metabolism and Virulence Associated Functions by Iron and XibR, a Novel Iron Binding Transcription Factor, in the Plant Pathogen Xanthomonas

    Science.gov (United States)

    Pandey, Sheo Shankar; Patnana, Pradeep Kumar; Lomada, Santosh Kumar; Tomar, Archana; Chatterjee, Subhadeep

    2016-01-01

    Abilities of bacterial pathogens to adapt to the iron limitation present in hosts is critical to their virulence. Bacterial pathogens have evolved diverse strategies to coordinately regulate iron metabolism and virulence associated functions to maintain iron homeostasis in response to changing iron availability in the environment. In many bacteria the ferric uptake regulator (Fur) functions as transcription factor that utilize ferrous form of iron as cofactor to regulate transcription of iron metabolism and many cellular functions. However, mechanisms of fine-tuning and coordinated regulation of virulence associated function beyond iron and Fur-Fe2+ remain undefined. In this study, we show that a novel transcriptional regulator XibR (named X anthomonas iron binding regulator) of the NtrC family, is required for fine-tuning and co-coordinately regulating the expression of several iron regulated genes and virulence associated functions in phytopathogen Xanthomonas campestris pv. campestris (Xcc). Genome wide expression analysis of iron-starvation stimulon and XibR regulon, GUS assays, genetic and functional studies of xibR mutant revealed that XibR positively regulates functions involved in iron storage and uptake, chemotaxis, motility and negatively regulates siderophore production, in response to iron. Furthermore, chromatin immunoprecipitation followed by quantitative real-time PCR indicated that iron promoted binding of the XibR to the upstream regulatory sequence of operon’s involved in chemotaxis and motility. Circular dichroism spectroscopy showed that purified XibR bound ferric form of iron. Electrophoretic mobility shift assay revealed that iron positively affected the binding of XibR to the upstream regulatory sequences of the target virulence genes, an effect that was reversed by ferric iron chelator deferoxamine. Taken together, these data revealed that how XibR coordinately regulates virulence associated and iron metabolism functions in Xanthomonads in

  20. Co-regulation of Iron Metabolism and Virulence Associated Functions by Iron and XibR, a Novel Iron Binding Transcription Factor, in the Plant Pathogen Xanthomonas.

    Directory of Open Access Journals (Sweden)

    Sheo Shankar Pandey

    2016-11-01

    Full Text Available Abilities of bacterial pathogens to adapt to the iron limitation present in hosts is critical to their virulence. Bacterial pathogens have evolved diverse strategies to coordinately regulate iron metabolism and virulence associated functions to maintain iron homeostasis in response to changing iron availability in the environment. In many bacteria the ferric uptake regulator (Fur functions as transcription factor that utilize ferrous form of iron as cofactor to regulate transcription of iron metabolism and many cellular functions. However, mechanisms of fine-tuning and coordinated regulation of virulence associated function beyond iron and Fur-Fe2+ remain undefined. In this study, we show that a novel transcriptional regulator XibR (named Xanthomonas iron binding regulator of the NtrC family, is required for fine-tuning and co-coordinately regulating the expression of several iron regulated genes and virulence associated functions in phytopathogen Xanthomonas campestris pv. campestris (Xcc. Genome wide expression analysis of iron-starvation stimulon and XibR regulon, GUS assays, genetic and functional studies of xibR mutant revealed that XibR positively regulates functions involved in iron storage and uptake, chemotaxis, motility and negatively regulates siderophore production, in response to iron. Furthermore, chromatin immunoprecipitation followed by quantitative real-time PCR indicated that iron promoted binding of the XibR to the upstream regulatory sequence of operon's involved in chemotaxis and motility. Circular dichroism spectroscopy showed that purified XibR bound ferric form of iron. Electrophoretic mobility shift assay revealed that iron positively affected the binding of XibR to the upstream regulatory sequences of the target virulence genes, an effect that was reversed by ferric iron chelator deferoxamine. Taken together, these data revealed that how XibR coordinately regulates virulence associated and iron metabolism functions in

  1. Zonulin and iron metabolism in heart transplant recipients.

    Science.gov (United States)

    Przybyłowski, P; Nowak, E; Janik, L; Wasilewski, G; Kozlowska, S; Małyszko, J

    2014-10-01

    In patients after heart transplantation, anemia is relatively common and is associated with impaired kidney function, subclinical inflammatory state, and immunosuppressive treatment. Zonulin-prehaptoglibin-2 is newly discovered protein with poorly defined function. Hemoglobin binds haptoglobin, and this stable complex prevents oxidative stress caused by hemoglobin. Zonulin is necessary for integrity of intracellular tight junction in the gut. Taking into consideration iron metabolism, including its absorption in the gut, the aim of this study was to assess zonulin levels in heart transplant recipients and their possible correlations with iron status, immunosuppressive therapy, and kidney function. The study was performed with 80 stable heart transplant recipients and 22 healthy volunteers. Zonulin, iron status, and inflammatory markers were assessed with the use of commercially available kits. Zonulin correlated with intraventricular diameter (r = 0.30; P zonulin and iron status. Zonulin was significantly lower in heart transplant recipients than in healthy volunteers (P zonulin level. Zonulin, despite its effect on the absorption of different nutrients and other substances and hypothethic role in oxidative stress, seems not to play a role in the pathogenesis of anemia in heart transplant recipients. Its physiologic role remains obscure.

  2. Effect of chronic ethanol administration on iron metabolism in the rat

    International Nuclear Information System (INIS)

    Sanchez, J.; Casas, M.; Rama, R.

    1988-01-01

    This study shows that the ingestion of ethanol provokes alterations in iron metabolism which may lead to iron overload. Impaired release of reticuloendothelial iron was shown by a decrease of the maximum red blood cell utilization when radioactive iron was supplied as colloidal iron. An impairment in the erythropoietic activity of ethanoltreated animals was also observed, as can be seen from the reduced plasma iron turnover and red blood cell utilization within 24 h of iron administration. A rise in marrow transit time was also observed. In ethanol-treated rats there was an increase in the amount of iron retained both in the liver and the spleen. This was observed in both sexes and also in the offspring from ethanol-treated mothers. (author)

  3. Hepcidin: an important iron metabolism regulator in chronic kidney disease

    Directory of Open Access Journals (Sweden)

    Sandra Azevedo Antunes

    Full Text Available Abstract Anemia is a common complication and its impact on morbimortality in patients with chronic kidney disease (CKD is well known. The discovery of hepcidin and its functions has contributed to a better understanding of iron metabolism disorders in CKD anemia. Hepcidin is a peptide mainly produced by hepatocytes and, through a connection with ferroportin, it regulates iron absorption in the duodenum and its release of stock cells. High hepcidin concentrations described in patients with CKD, especially in more advanced stages are attributed to decreased renal excretion and increased production. The elevation of hepcidin has been associated with infection, inflammation, atherosclerosis, insulin resistance and oxidative stress. Some strategies were tested to reduce the effects of hepcidin in patients with CKD, however more studies are necessary to assess the impact of its modulation in the management of anemia in this population.

  4. Hepcidin: A Critical Regulator of Iron Metabolism during Hypoxia

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    Korry J. Hintze

    2011-01-01

    Full Text Available Iron status affects cognitive and physical performance in humans. Recent evidence indicates that iron balance is a tightly regulated process affected by a series of factors other than diet, to include hypoxia. Hypoxia has profound effects on iron absorption and results in increased iron acquisition and erythropoiesis when humans move from sea level to altitude. The effects of hypoxia on iron balance have been attributed to hepcidin, a central regulator of iron homeostasis. This paper will focus on the molecular mechanisms by which hypoxia affects hepcidin expression, to include a review of the hypoxia inducible factor (HIF/hypoxia response element (HRE system, as well as recent evidence indicating that localized adipose hypoxia due to obesity may affect hepcidin signaling and organismal iron metabolism.

  5. Clinical features and dysfunctions of iron metabolism in Parkinson disease patients with hyper echogenicity in substantia nigra: a cross-sectional study.

    Science.gov (United States)

    Yu, Shu-Yang; Cao, Chen-Jie; Zuo, Li-Jun; Chen, Ze-Jie; Lian, Teng-Hong; Wang, Fang; Hu, Yang; Piao, Ying-Shan; Li, Li-Xia; Guo, Peng; Liu, Li; Yu, Qiu-Jin; Wang, Rui-Dan; Chan, Piu; Chen, Sheng-di; Wang, Xiao-Min; Zhang, Wei

    2018-01-17

    Transcranial ultrasound is a useful tool for providing the evidences for the early diagnosis and differential diagnosis of Parkinson disease (PD). However, the relationship between hyper echogenicity in substantia nigra (SN) and clinical symptoms of PD patients remains unknown, and the role of dysfunction of iron metabolism on the pathogenesis of SN hyper echogenicity is unclear. PD patients was detected by transcranial sonography and divided into with no hyper echogenicity (PDSN-) group and with hyper echogenicity (PDSN+) group. Motor symptoms (MS) and non-motor symptoms (NMS) were evaluated, and the levels of iron and related proteins in serum and cerebrospinal fluid (CSF) were detected for PD patients. Data comparison between the two groups and correlation analyses were performed. PDSN+ group was significantly older, and had significantly older age of onset, more advanced Hohen-Yahr stage, higher SCOPA-AUT score and lower MoCA score than PDSN- group (P hyper echogenicity in SN are older, at more advanced disease stage, have severer motor symptoms, and non-motor symptoms of cognitive impairment and autonomic dysfunction. Hyper echogenicity of SN in PD patients is related to dysfunction of iron metabolism, involving increased iron transport from peripheral system to central nervous system, reduction of intracellular iron release and excessive iron deposition in brain.

  6. Oxidative Stress and the Homeodynamics of Iron Metabolism

    Science.gov (United States)

    Bresgen, Nikolaus; Eckl, Peter M.

    2015-01-01

    Iron and oxygen share a delicate partnership since both are indispensable for survival, but if the partnership becomes inadequate, this may rapidly terminate life. Virtually all cell components are directly or indirectly affected by cellular iron metabolism, which represents a complex, redox-based machinery that is controlled by, and essential to, metabolic requirements. Under conditions of increased oxidative stress—i.e., enhanced formation of reactive oxygen species (ROS)—however, this machinery may turn into a potential threat, the continued requirement for iron promoting adverse reactions such as the iron/H2O2-based formation of hydroxyl radicals, which exacerbate the initial pro-oxidant condition. This review will discuss the multifaceted homeodynamics of cellular iron management under normal conditions as well as in the context of oxidative stress. PMID:25970586

  7. Hyperferritinemia and iron metabolism in Gaucher disease: Potential pathophysiological implications.

    Science.gov (United States)

    Regenboog, Martine; van Kuilenburg, André B P; Verheij, Joanne; Swinkels, Dorine W; Hollak, Carla E M

    2016-11-01

    Gaucher disease (GD) is characterized by large amounts of lipid-storing macrophages and is associated with accumulation of iron. High levels of ferritin are a hallmark of the disease. The precise mechanism underlying the changes in iron metabolism has not been elucidated. A systematic search was conducted to summarize available evidence from the literature on iron metabolism in GD and its potential pathophysiological implications. We conclude that in GD, a chronic low grade inflammation state can lead to high ferritin levels and increased hepcidin transcription with subsequent trapping of ferritin in macrophages. Extensive GD manifestations with severe anemia or extreme splenomegaly can lead to a situation of iron-overload resembling hemochromatosis. We hypothesize that specifically this latter situation carries a risk for the occurrence of associated conditions such as the increased cancer risk, metabolic syndrome and neurodegeneration. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Correlations between abnormal iron metabolism and non-motor symptoms in Parkinson's disease.

    Science.gov (United States)

    Xu, Wu; Zhi, Yan; Yuan, Yongsheng; Zhang, Bingfeng; Shen, Yuting; Zhang, Hui; Zhang, Kezhong; Xu, Yun

    2018-07-01

    Despite a growing body of evidence suggests that abnormal iron metabolism plays an important role in the pathogenesis of Parkinson's disease (PD), few studies explored its role in non-motor symptoms (NMS) of PD. The present study aimed to investigate the relationship between abnormal iron metabolism and NMS of PD. Seventy PD patients and 64 healthy controls were consecutively recruited to compare serum iron, ceruloplasmin, ferritin, and transferrin levels. We evaluated five classic NMS, including depression, anxiety, pain, sleep disorder, and autonomic dysfunction in PD patients using the Hamilton Depression Scale (HAMD), the Hamilton Anxiety Scale (HAMA), the short form of the McGill Pain Questionnaire, the Pittsburgh Sleep Quality Index and the Scale for Outcomes in Parkinson's disease for Autonomic Symptoms, respectively. Hierarchical multiple regression analysis was used to investigate the correlations between abnormal iron metabolism and NMS. No differences in serum ceruloplasmin and ferritin levels were examined between PD patients and healthy controls, but we observed significantly decreased serum iron levels and increased serum transferrin levels in PD patients in comparison with healthy controls. After eliminating confounding factors, HAMD scores and HAMA scores were both negatively correlated with serum iron levels and positively correlated with serum transferrin levels. In summary, abnormal iron metabolism might play a crucial role in the pathogenesis of depression and anxiety in PD. Serums levels of iron and transferrin could be peripheral markers for depression and anxiety in PD.

  9. The role of mitochondria in cellular iron-sulfur protein biogenesis and iron metabolism.

    Science.gov (United States)

    Lill, Roland; Hoffmann, Bastian; Molik, Sabine; Pierik, Antonio J; Rietzschel, Nicole; Stehling, Oliver; Uzarska, Marta A; Webert, Holger; Wilbrecht, Claudia; Mühlenhoff, Ulrich

    2012-09-01

    Mitochondria play a key role in iron metabolism in that they synthesize heme, assemble iron-sulfur (Fe/S) proteins, and participate in cellular iron regulation. Here, we review the latter two topics and their intimate connection. The mitochondrial Fe/S cluster (ISC) assembly machinery consists of 17 proteins that operate in three major steps of the maturation process. First, the cysteine desulfurase complex Nfs1-Isd11 as the sulfur donor cooperates with ferredoxin-ferredoxin reductase acting as an electron transfer chain, and frataxin to synthesize an [2Fe-2S] cluster on the scaffold protein Isu1. Second, the cluster is released from Isu1 and transferred toward apoproteins with the help of a dedicated Hsp70 chaperone system and the glutaredoxin Grx5. Finally, various specialized ISC components assist in the generation of [4Fe-4S] clusters and cluster insertion into specific target apoproteins. Functional defects of the core ISC assembly machinery are signaled to cytosolic or nuclear iron regulatory systems resulting in increased cellular iron acquisition and mitochondrial iron accumulation. In fungi, regulation is achieved by iron-responsive transcription factors controlling the expression of genes involved in iron uptake and intracellular distribution. They are assisted by cytosolic multidomain glutaredoxins which use a bound Fe/S cluster as iron sensor and additionally perform an essential role in intracellular iron delivery to target metalloproteins. In mammalian cells, the iron regulatory proteins IRP1, an Fe/S protein, and IRP2 act in a post-transcriptional fashion to adjust the cellular needs for iron. Thus, Fe/S protein biogenesis and cellular iron metabolism are tightly linked to coordinate iron supply and utilization. This article is part of a Special Issue entitled: Cell Biology of Metals. Copyright © 2012 Elsevier B.V. All rights reserved.

  10. Gene expression profiling in Entamoeba histolytica identifies key components in iron uptake and metabolism.

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    Nora Adriana Hernández-Cuevas

    Full Text Available Entamoeba histolytica is an ameboid parasite that causes colonic dysentery and liver abscesses in humans. The parasite encounters dramatic changes in iron concentration during its invasion of the host, with relatively low levels in the intestinal lumen and then relatively high levels in the blood and liver. The liver notably contains sources of iron; therefore, the parasite's ability to use these sources might be relevant to its survival in the liver and thus the pathogenesis of liver abscesses. The objective of the present study was to identify factors involved in iron uptake, use and storage in E. histolytica. We compared the respective transcriptomes of E. histolytica trophozoites grown in normal medium (containing around 169 µM iron, low-iron medium (around 123 µM iron, iron-deficient medium (around 91 µM iron, and iron-deficient medium replenished with hemoglobin. The differentially expressed genes included those coding for the ATP-binding cassette transporters and major facilitator transporters (which share homology with bacterial siderophores and heme transporters and genes involved in heme biosynthesis and degradation. Iron deficiency was associated with increased transcription of genes encoding a subset of cell signaling molecules, some of which have previously been linked to adaptation to the intestinal environment and virulence. The present study is the first to have assessed the transcriptome of E. histolytica grown under various iron concentrations. Our results provide insights into the pathways involved in iron uptake and metabolism in this parasite.

  11. Gene expression profiling in Entamoeba histolytica identifies key components in iron uptake and metabolism.

    Science.gov (United States)

    Hernández-Cuevas, Nora Adriana; Weber, Christian; Hon, Chung-Chau; Guillen, Nancy

    2014-01-01

    Entamoeba histolytica is an ameboid parasite that causes colonic dysentery and liver abscesses in humans. The parasite encounters dramatic changes in iron concentration during its invasion of the host, with relatively low levels in the intestinal lumen and then relatively high levels in the blood and liver. The liver notably contains sources of iron; therefore, the parasite's ability to use these sources might be relevant to its survival in the liver and thus the pathogenesis of liver abscesses. The objective of the present study was to identify factors involved in iron uptake, use and storage in E. histolytica. We compared the respective transcriptomes of E. histolytica trophozoites grown in normal medium (containing around 169 µM iron), low-iron medium (around 123 µM iron), iron-deficient medium (around 91 µM iron), and iron-deficient medium replenished with hemoglobin. The differentially expressed genes included those coding for the ATP-binding cassette transporters and major facilitator transporters (which share homology with bacterial siderophores and heme transporters) and genes involved in heme biosynthesis and degradation. Iron deficiency was associated with increased transcription of genes encoding a subset of cell signaling molecules, some of which have previously been linked to adaptation to the intestinal environment and virulence. The present study is the first to have assessed the transcriptome of E. histolytica grown under various iron concentrations. Our results provide insights into the pathways involved in iron uptake and metabolism in this parasite.

  12. Proteomic analysis of iron acquisition, metabolic and regulatory responses of Yersinia pestis to iron starvation

    Directory of Open Access Journals (Sweden)

    Fleischmann Robert D

    2010-01-01

    Full Text Available Abstract Background The Gram-negative bacterium Yersinia pestis is the causative agent of the bubonic plague. Efficient iron acquisition systems are critical to the ability of Y. pestis to infect, spread and grow in mammalian hosts, because iron is sequestered and is considered part of the innate host immune defence against invading pathogens. We used a proteomic approach to determine expression changes of iron uptake systems and intracellular consequences of iron deficiency in the Y. pestis strain KIM6+ at two physiologically relevant temperatures (26°C and 37°C. Results Differential protein display was performed for three Y. pestis subcellular fractions. Five characterized Y. pestis iron/siderophore acquisition systems (Ybt, Yfe, Yfu, Yiu and Hmu and a putative iron/chelate outer membrane receptor (Y0850 were increased in abundance in iron-starved cells. The iron-sulfur (Fe-S cluster assembly system Suf, adapted to oxidative stress and iron starvation in E. coli, was also more abundant, suggesting functional activity of Suf in Y. pestis under iron-limiting conditions. Metabolic and reactive oxygen-deactivating enzymes dependent on Fe-S clusters or other iron cofactors were decreased in abundance in iron-depleted cells. This data was consistent with lower activities of aconitase and catalase in iron-starved vs. iron-rich cells. In contrast, pyruvate oxidase B which metabolizes pyruvate via electron transfer to ubiquinone-8 for direct utilization in the respiratory chain was strongly increased in abundance and activity in iron-depleted cells. Conclusions Many protein abundance differences were indicative of the important regulatory role of the ferric uptake regulator Fur. Iron deficiency seems to result in a coordinated shift from iron-utilizing to iron-independent biochemical pathways in the cytoplasm of Y. pestis. With growth temperature as an additional variable in proteomic comparisons of the Y. pestis fractions (26°C and 37°C, there was

  13. Correlation of iron deposition and change of gliocyte metabolism in the basal ganglia region evaluated using magnetic resonance imaging techniques: an in vivo study

    OpenAIRE

    Liu, Haodi; Wang, Xiaoming

    2016-01-01

    Introduction We assessed the correlation between iron deposition and the change of gliocyte metabolism in healthy subjects? basal ganglia region, by using 3D-enhanced susceptibility weighted angiography (ESWAN) and proton magnetic resonance spectroscopy (1H-MRS). Material and methods Seventy-seven healthy volunteers (39 female and 38 male subjects; age range: 24?82 years old) were enrolled in the experiment including ESWAN and proton MRS sequences, consent for which was provided by themselves...

  14. Role of the Irr protein in the regulation of iron metabolism in Rhodobacter sphaeroides.

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    Verena Peuser

    Full Text Available In Rhizobia the Irr protein is an important regulator for iron-dependent gene expression. We studied the role of the Irr homolog RSP_3179 in the photosynthetic alpha-proteobacterium Rhodobacter sphaeroides. While Irr had little effect on growth under iron-limiting or non-limiting conditions its deletion resulted in increased resistance to hydrogen peroxide and singlet oxygen. This correlates with an elevated expression of katE for catalase in the Irr mutant compared to the wild type under non-stress conditions. Transcriptome studies revealed that Irr affects the expression of genes for iron metabolism, but also has some influence on genes involved in stress response, citric acid cycle, oxidative phosphorylation, transport, and photosynthesis. Most genes showed higher expression levels in the wild type than in the mutant under normal growth conditions indicating an activator function of Irr. Irr was however not required to activate genes of the iron metabolism in response to iron limitation, which showed even stronger induction in the absence of Irr. This was also true for genes mbfA and ccpA, which were verified as direct targets for Irr. Our results suggest that in R. sphaeroides Irr diminishes the strong induction of genes for iron metabolism under iron starvation.

  15. Mice overexpressing both non-mutated human SOD1 and mutated SOD1G93A genes: a competent experimental model for studying iron metabolism in amyotrophic lateral sclerosis

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    Anna eGajowiak

    2016-01-01

    Full Text Available Amyotrophic lateral sclerosis (ALS is a progressive neurodegenerative disease characterized by degeneration and loss of motor neurons in the spinal cord, brainstem and motor cortex. Up to 10% of ALS cases are inherited (familial, fALS and associated with mutations, frequently in the superoxide dismutase 1 (SOD1 gene. Rodent transgenic models of ALS are often used to elucidate a complex pathogenesis of this disease. Of importance, both ALS patients and animals carrying mutated human SOD1 gene show symptoms of oxidative stress and iron metabolism misregulation. The aim of our study was to characterize changes in iron metabolism in one of the most commonly used models of ALS – transgenic mice overexpressing human mutated SOD1G93A gene. We analyzed the expression of iron-related genes in asymptomatic, 2-month old and symptomatic, 4-month old SOD1G93A mice. In parallel, respective age-matched mice overexpressing human non-mutated SOD1 transgene and control mice were analyzed. We demonstrate that the overexpression of both SOD1 and SOD1G93A genes account for a substantial increase in SOD1 protein levels and activity in selected tissues and that not all the changes in iron metabolism genes expression are specific for the overexpression of the mutated form of SOD1.

  16. Relationship between indices of iron status and metabolic syndrome in an Iranian population

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    Niloofar Tavakoli-Hoseini

    2014-11-01

    Full Text Available Introduction: Iron overload may contribute to the pathogenesis of metabolic syndrome (MS. A growing body of evidence indicates that the oxidative stress that results from excess tissue iron can leads to insulin resistance, tissue damage, and other complications observed in MS. The objective of this study was to investigate indices of iron status including serum ferritin, iron, total iron binding capacity (TIBC levels, and full blood cell count, together with demographic and anthropometric characteristics, lipid profile components, and other biochemical parameters in subjects with and with-out MS. Methods: A total of, 385 individuals (176 with and 209 subjects without MS according to the International Diabetes Federation’s (IDF criteria were recruited. Indices of iron status and other clinical and biochemical parameters were determined in MS patients and healthy controls using standard methods. Results: Higher serum iron and ferritin values were observed in subjects with MS in compared to healthy controls (P 0.050. Among the other indices, only red blood cell (RBC was associated considerably with the presence of MS (P < 0.050. Conclusion: Our data indicate that even in a country with a comparatively high prevalence of iron deficiency, serum iron and ferritin values in MS patients are higher than healthy controls. The reason why ferritin and iron are higher in MS patient may be related to dietary factors.

  17. Study on Renal Anemia: A Double Tracer Study on Metabolism and Red Cell Life Span in Chronic Renal Diseases using Radioactive Iron (59Fe) and Chromium (51Cr)

    International Nuclear Information System (INIS)

    Jung, Kyung Tae; Lee, Mun Ho

    1968-01-01

    The ferrokinetics and red cell life spans of the patients with chronic glomerulonephritis were investigated by the double tracing method using radioactive iron ( 59 Fe) and chromium ( 51 Cr). According to the serum NPN levels, the patients were subdivided into 3 groups: Group 1. 6 patients, had the levels below 40 mg/dl. Group 2. 6 patients, had the levels between 41 mg/dl to 80 mg/dl. Group 3. 10 patients had the levels above 80 mg/dl. The results were as follows: 1) Red blood cell, hematocrit and hemoglobin values were moderately reduced in patients with normal serum NPN levels, while markedly reduced in patients with elevated serum NPN levels. 2) The plasma volume was increased, while the red cell volume was decreased in patients with elevated serum NPN levels, hence, total blood volume was unchanged. 3) The serum iron level was slightly reduced in patients of groups 1 and 2, while was within the normal ranges in patients of group 3. 4) i) In patients with normal serum NPN levels, the plasma iron disappearance rate, red cell iron utilization rate, red cell iron turnover rate, daily red cell iron renewal rate, circulating red cell iron and red cell iron concentration were within the normal ranges, while the plasma iron turnover rate was slightly reduced. ii) In patients with elevated serum NPN levels, the plasma iron disappearance rate was delayed, while the plasma iron turnover rate was within the normal ranges. The red cell iron utilization rate, red cell iron turnover rate and circulating red cell iron were decreased and the period in which the red cell iron utilization rate reached its peak was delayed in Group 3 patients. The daily red cell iron renewal rate and the red cell iron concentration were unchanged. iii) The mean red cell life span was within the normal ranges in patients with normal serum NPN levels, while was shortened in patients with elevated serum NPN levels.

  18. Genomic Organization and Expression of Iron Metabolism Genes in the Emerging Pathogenic Mold Scedosporium apiospermum

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    Yohann Le Govic

    2018-04-01

    Full Text Available The ubiquitous mold Scedosporium apiospermum is increasingly recognized as an emerging pathogen, especially among patients with underlying disorders such as immunodeficiency or cystic fibrosis (CF. Indeed, it ranks the second among the filamentous fungi colonizing the respiratory tract of CF patients. However, our knowledge about virulence factors of this fungus is still limited. The role of iron-uptake systems may be critical for establishment of Scedosporium infections, notably in the iron-rich environment of the CF lung. Two main strategies are employed by fungi to efficiently acquire iron from their host or from their ecological niche: siderophore production and reductive iron assimilation (RIA systems. The aim of this study was to assess the existence of orthologous genes involved in iron metabolism in the recently sequenced genome of S. apiospermum. At first, a tBLASTn analysis using A. fumigatus iron-related proteins as query revealed orthologs of almost all relevant loci in the S. apiospermum genome. Whereas the genes putatively involved in RIA were randomly distributed, siderophore biosynthesis and transport genes were organized in two clusters, each containing a non-ribosomal peptide synthetase (NRPS whose orthologs in A. fumigatus have been described to catalyze hydroxamate siderophore synthesis. Nevertheless, comparative genomic analysis of siderophore-related clusters showed greater similarity between S. apiospermum and phylogenetically close molds than with Aspergillus species. The expression level of these genes was then evaluated by exposing conidia to iron starvation and iron excess. The expression of several orthologs of A. fumigatus genes involved in siderophore-based iron uptake or RIA was significantly induced during iron starvation, and conversely repressed in iron excess conditions. Altogether, these results indicate that S. apiospermum possesses the genetic information required for efficient and competitive iron uptake

  19. Dietary iron controls circadian hepatic glucose metabolism through heme synthesis.

    Science.gov (United States)

    Simcox, Judith A; Mitchell, Thomas Creighton; Gao, Yan; Just, Steven F; Cooksey, Robert; Cox, James; Ajioka, Richard; Jones, Deborah; Lee, Soh-Hyun; King, Daniel; Huang, Jingyu; McClain, Donald A

    2015-04-01

    The circadian rhythm of the liver maintains glucose homeostasis, and disruption of this rhythm is associated with type 2 diabetes. Feeding is one factor that sets the circadian clock in peripheral tissues, but relatively little is known about the role of specific dietary components in that regard. We assessed the effects of dietary iron on circadian gluconeogenesis. Dietary iron affects circadian glucose metabolism through heme-mediated regulation of the interaction of nuclear receptor subfamily 1 group d member 1 (Rev-Erbα) with its cosuppressor nuclear receptor corepressor 1 (NCOR). Loss of regulated heme synthesis was achieved by aminolevulinic acid (ALA) treatment of mice or cultured cells to bypass the rate-limiting enzyme in hepatic heme synthesis, ALA synthase 1 (ALAS1). ALA treatment abolishes differences in hepatic glucose production and in the expression of gluconeogenic enzymes seen with variation of dietary iron. The differences among diets are also lost with inhibition of heme synthesis with isonicotinylhydrazine. Dietary iron modulates levels of peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α), a transcriptional activator of ALAS1, to affect hepatic heme. Treatment of mice with the antioxidant N-acetylcysteine diminishes PGC-1α variation observed among the iron diets, suggesting that iron is acting through reactive oxygen species signaling. © 2015 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

  20. Human macrophage hemoglobin-iron metabolism in vitro

    International Nuclear Information System (INIS)

    Custer, G.; Balcerzak, S.; Rinehart, J.

    1982-01-01

    An entirely in vitro technique was employed to characterize hemoglobin-iron metabolism by human macrophages obtained by culture of blood monocytes and pulmonary alveolar macrophages. Macrophages phagocytized about three times as many erythrocytes as monocytes and six times as many erythrocytes as pulmonary alveolar macrophages. The rate of subsequent release of 59 Fe to the extracellular transferrin pool was two- to fourfold greater for macrophages as compared to the other two cell types. The kinetics of 59 Fe-transferrin release were characterized by a relatively rapid early phase (hours 1-4) followed by a slow phase (hours 4-72) for all three cell types. Intracellular movement of iron was characterized by a rapid shift from hemoglobin to ferritin that was complete with the onset of the slow phase of extracellular release. A transient increase in 59 Fe associated with an intracellular protein eluting with transferrin was also observed within 1 hour after phagocytosis. The process of hemoglobin-iron release to extracellular transferrin was inhibited at 4 degrees C but was unaffected by inhibitory of protein synthesis, glycolysis, microtubule function, and microfilament function. These data emphasize the rapidity of macrophage hemoglobin iron metabolism, provide a model for characterization of this process in vitro, and in general confirm data obtained utilizing in vivo animal models

  1. Females Are Protected From Iron?Overload Cardiomyopathy Independent of Iron Metabolism: Key Role of Oxidative Stress

    OpenAIRE

    Das, Subhash K.; Patel, Vaibhav B.; Basu, Ratnadeep; Wang, Wang; DesAulniers, Jessica; Kassiri, Zamaneh; Oudit, Gavin Y.

    2017-01-01

    Background Sex?related differences in cardiac function and iron metabolism exist in humans and experimental animals. Male patients and preclinical animal models are more susceptible to cardiomyopathies and heart failure. However, whether similar differences are seen in iron?overload cardiomyopathy is poorly understood. Methods and Results Male and female wild?type and hemojuvelin?null mice were injected and fed with a high?iron diet, respectively, to develop secondary iron overload and geneti...

  2. Copper metabolism and its interactions with dietary iron, zinc, tin and selenium in rats

    NARCIS (Netherlands)

    Yu, S.

    1993-01-01

    This thesis describes various studies on copper metabolism and its interactions with selected dietary trace elements in rats. The rats were fed purified diets throughout. High intakes of iron or tin reduced copper concentrations in plasma, liver and kidneys. The dietary treatments also

  3. Magnetic study of iron sorbitol

    Energy Technology Data Exchange (ETDEWEB)

    Lazaro, F.J. E-mail: osoro@posta.unizar.es; Larrea, A.; Abadia, A.R.; Romero, M.S

    2002-09-01

    A magnetic study of iron sorbitol, an iron-containing drug to treat the iron deficiency anemia is presented. Transmission electron microscopy reveals that the system contains nanometric particles with an average diameter of 3 nm whose composition is close to two-line ferrihydrite. The characterisation by magnetisation and AC susceptibility measurements indicates superparamagnetic behaviour with progressive magnetic blocking starting at 8 K. The quantitative analysis of the magnetic results indicates that the system consists of an assembly of very small magnetic moments, presumably originated by spin uncompensation of the antiferromagnetic nanoparticles, with Arrhenius type magnetic dynamics.

  4. Novel insights into iron metabolism by integrating deletome and transcriptome analysis in an iron deficiency model of the yeast Saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    Arkin Adam P

    2009-03-01

    components. This should be taken into consideration when designing and analyzing data from these type of studies. We used this and other published data to develop a molecular interaction network of iron metabolism in yeast.

  5. Studies on the pathogenesis in iron deficiency anemia Part 1. Urinary iron excretion in iron deficiency anemia patients and rats in various iron states

    OpenAIRE

    中西,徳彦

    1991-01-01

    In the "iron excretion test" , urinary iron excretion after injection of saccharated iron oxide has been reported to be accelerated in relapsing idiopathic iron deficiency anemia. To determine the relevance of urinary iron excretion to clinical factors other than iron metabolism, 15 clinical parameters were evaluated. The serum creatinine level was positively and the serum albumin level was negatively correlated with urinary iron excretion, showing coefficients of r=0.97,-0.86 respectively, a...

  6. Studying Irony Detection Beyond Ironic Criticism: Let's Include Ironic Praise

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    Richard Bruntsch

    2017-04-01

    Full Text Available Studies of irony detection have commonly used ironic criticisms (i.e., mock positive evaluation of negative circumstances as stimulus materials. Another basic type of verbal irony, ironic praise (i.e., mock negative evaluation of positive circumstances is largely absent from studies on individuals' aptitude to detect verbal irony. However, it can be argued that ironic praise needs to be considered in order to investigate the detection of irony in the variety of its facets. To explore whether the detection ironic praise has a benefit beyond ironic criticism, three studies were conducted. In Study 1, an instrument (Test of Verbal Irony Detection Aptitude; TOVIDA was constructed and its factorial structure was tested using N = 311 subjects. The TOVIDA contains 26 scenario-based items and contains two scales for the detection of ironic criticism vs. ironic praise. To validate the measurement method, the two scales of the TOVIDA were experimentally evaluated with N = 154 subjects in Study 2. In Study 3, N = 183 subjects were tested to explore personality and ability correlates of the two TOVIDA scales. Results indicate that the co-variance between the ironic TOVIDA items was organized by two inter-correlated but distinct factors: one representing ironic praise detection aptitude and one representing ironic criticism detection aptitude. Experimental validation showed that the TOVIDA items truly contain irony and that item scores reflect irony detection. Trait bad mood and benevolent humor (as a facet of the sense of humor were found as joint correlates for both ironic criticism and ironic praise detection scores. In contrast, intelligence, trait cheerfulness, and corrective humor were found as unique correlates of ironic praise detection scores, even when statistically controlling for the aptitude to detect ironic criticism. Our results indicate that the aptitude to detect ironic praise can be seen as distinct from the aptitude to detect ironic

  7. Females Are Protected From Iron-Overload Cardiomyopathy Independent of Iron Metabolism: Key Role of Oxidative Stress.

    Science.gov (United States)

    Das, Subhash K; Patel, Vaibhav B; Basu, Ratnadeep; Wang, Wang; DesAulniers, Jessica; Kassiri, Zamaneh; Oudit, Gavin Y

    2017-01-23

    Sex-related differences in cardiac function and iron metabolism exist in humans and experimental animals. Male patients and preclinical animal models are more susceptible to cardiomyopathies and heart failure. However, whether similar differences are seen in iron-overload cardiomyopathy is poorly understood. Male and female wild-type and hemojuvelin-null mice were injected and fed with a high-iron diet, respectively, to develop secondary iron overload and genetic hemochromatosis. Female mice were completely protected from iron-overload cardiomyopathy, whereas iron overload resulted in marked diastolic dysfunction in male iron-overloaded mice based on echocardiographic and invasive pressure-volume analyses. Female mice demonstrated a marked suppression of iron-mediated oxidative stress and a lack of myocardial fibrosis despite an equivalent degree of myocardial iron deposition. Ovariectomized female mice with iron overload exhibited essential pathophysiological features of iron-overload cardiomyopathy showing distinct diastolic and systolic dysfunction, severe myocardial fibrosis, increased myocardial oxidative stress, and increased expression of cardiac disease markers. Ovariectomy prevented iron-induced upregulation of ferritin, decreased myocardial SERCA2a levels, and increased NCX1 levels. 17β-Estradiol therapy rescued the iron-overload cardiomyopathy in male wild-type mice. The responses in wild-type and hemojuvelin-null female mice were remarkably similar, highlighting a conserved mechanism of sex-dependent protection from iron-overload-mediated cardiac injury. Male and female mice respond differently to iron-overload-mediated effects on heart structure and function, and females are markedly protected from iron-overload cardiomyopathy. Ovariectomy in female mice exacerbated iron-induced myocardial injury and precipitated severe cardiac dysfunction during iron-overload conditions, whereas 17β-estradiol therapy was protective in male iron-overloaded mice.

  8. Role of nitric oxide in cellular iron metabolism.

    Science.gov (United States)

    Kim, Sangwon; Ponka, Prem

    2003-03-01

    Iron regulatory proteins (IRP1 and IRP2) control the synthesis of transferrin receptors (TfR) and ferritin by binding to iron-responsive elements (IREs) which are located in the 3' untranslated region (UTR) and the 5' UTR of their respective mRNAs. Cellular iron levels affect binding of IRPs to IREs and consequently expression of TfR and ferritin. Moreover, NO*, a redox species of nitric oxide that interacts primarily with iron, can activate IRP1 RNA-binding activity resulting in an increase in TfR mRNA levels. We have shown that treatment of RAW 264.7 cells (a murine macrophage cell line) with NO+ (nitrosonium ion, which causes S-nitrosylation of thiol groups) resulted in a rapid decrease in RNA-binding of IRP2, followed by IRP2 degradation, and these changes were associated with a decrease in TfR mRNA levels. Moreover, we demonstrated that stimulation of RAW 264.7 cells with lipopolysaccharide (LPS) and interferon-gamma (IFN-gamma) increased IRP1 binding activity, whereas RNA-binding of IRP2 decreased and was followed by a degradation of this protein. Furthermore, the decrease of IRP2 binding/protein levels was associated with a decrease in TfR mRNA levels in LPS/IFN-gamma-treated cells, and these changes were prevented by inhibitors of inducible nitric oxide synthase. These results suggest that NO+-mediated degradation of IRP2 plays a major role in iron metabolism during inflammation.

  9. Hepcidin: an important iron metabolism regulator in chronic kidney disease.

    Science.gov (United States)

    Antunes, Sandra Azevedo; Canziani, Maria Eugênia Fernandes

    2016-01-01

    Anemia is a common complication and its impact on morbimortality in patients with chronic kidney disease (CKD) is well known. The discovery of hepcidin and its functions has contributed to a better understanding of iron metabolism disorders in CKD anemia. Hepcidin is a peptide mainly produced by hepatocytes and, through a connection with ferroportin, it regulates iron absorption in the duodenum and its release of stock cells. High hepcidin concentrations described in patients with CKD, especially in more advanced stages are attributed to decreased renal excretion and increased production. The elevation of hepcidin has been associated with infection, inflammation, atherosclerosis, insulin resistance and oxidative stress. Some strategies were tested to reduce the effects of hepcidin in patients with CKD, however more studies are necessary to assess the impact of its modulation in the management of anemia in this population. Resumo Anemia é uma complicação frequente e seu impacto na morbimortalidade é bem conhecido em pacientes com doença renal crônica (DRC). A descoberta da hepcidina e de suas funções contribuíram para melhor compreensão dos distúrbios do metabolismo de ferro na anemia da DRC. Hepcidina é um peptídeo produzido principalmente pelos hepatócitos, e através de sua ligação com a ferroportina, regula a absorção de ferro no duodeno e sua liberação das células de estoque. Altas concentrações de hepcidina descritas em pacientes com DRC, principalmente em estádios mais avançados, são atribuídas à diminuição da excreção renal e ao aumento de sua produção. Elevação de hepcidina tem sido associada à ocorrência de infecção, inflamação, aterosclerose, resistência à insulina e estresse oxidativo. Algumas estratégias foram testadas para diminuir os efeitos da hepcidina em pacientes com DRC, entretanto, serão necessários mais estudos para avaliar o impacto de sua modulação no manejo da anemia nessa população.

  10. Peculiarities of antioxidant system and iron metabolism in organism during development of tumor resistance to cisplatin.

    Science.gov (United States)

    Chekhun, V F; Lozovska, Y V; Burlaka, A P; Lukyanova, N Y; Todor, I N; Naleskina, L A

    2014-09-01

    To study in vivo the peculiarities of changes of iron metabolism and antioxidant system in dynamics of growth of Guerin carcinoma with different sensitivity to cisplatin. In order to evaluate the content of metallothionein-1 (MT-1) in tumor homogenates and blood serum of rats with cisplatin-sensitive and cisplatin-resistant Guerin carcinoma the immunoenzyme method was used. The evaluation of ceruloplasmin activity, content of "free iron" complexes, superoxide and NO-generating acti-vity of NADPH-oxidase and iNOS activity in neutrophils, blood serum and tumor homogenates was measured by EPR-spectro-scopy. Maximal accumulation of MT-1 in blood serum and tumor, more pronounced in resistant strain, at the border of latent and exponential phase of growth has been shown that is the evidence of protective role of this protein in the respect to the generation of free radical compounds. It has been determined that in animals with cisplatin-resistant strain of Guerin carcinoma, increase of "free iron" complexes is more apparent both on the level of tumor and organism on the background on increase of CP/TR ratio that is the consequence of organism antioxidant protection system disorder. Mentioned changes in metabolism of iron with its accumulation in tumor and further reprogramming of mitochondria metabolism and activity of NADPH-oxidase for non-transformed cells are favorable conditions for the formation of oxidative phenotype of tumor.

  11. Metabolomic profiling identifies potential pathways involved in the interaction of iron homeostasis with glucose metabolism

    Directory of Open Access Journals (Sweden)

    Lars Stechemesser

    2017-01-01

    Full Text Available Objective: Elevated serum ferritin has been linked to type 2 diabetes (T2D and adverse health outcomes in subjects with the Metabolic Syndrome (MetS. As the mechanisms underlying the negative impact of excess iron have so far remained elusive, we aimed to identify potential links between iron homeostasis and metabolic pathways. Methods: In a cross-sectional study, data were obtained from 163 patients, allocated to one of three groups: (1 lean, healthy controls (n = 53, (2 MetS without hyperferritinemia (n = 54 and (3 MetS with hyperferritinemia (n = 56. An additional phlebotomy study included 29 patients with biopsy-proven iron overload before and after iron removal. A detailed clinical and biochemical characterization was obtained and metabolomic profiling was performed via a targeted metabolomics approach. Results: Subjects with MetS and elevated ferritin had higher fasting glucose (p < 0.001, HbA1c (p = 0.035 and 1 h glucose in oral glucose tolerance test (p = 0.002 compared to MetS subjects without iron overload, whereas other clinical and biochemical features of the MetS were not different. The metabolomic study revealed significant differences between MetS with high and low ferritin in the serum concentrations of sarcosine, citrulline and particularly long-chain phosphatidylcholines. Methionine, glutamate, and long-chain phosphatidylcholines were significantly different before and after phlebotomy (p < 0.05 for all metabolites. Conclusions: Our data suggest that high serum ferritin concentrations are linked to impaired glucose homeostasis in subjects with the MetS. Iron excess is associated to distinct changes in the serum concentrations of phosphatidylcholine subsets. A pathway involving sarcosine and citrulline also may be involved in iron-induced impairment of glucose metabolism. Author Video: Author Video Watch what authors say about their articles Keywords: Metabolomics, Hyperferritinemia, Iron overload, Metabolic

  12. Nitrate-Dependent Iron Oxidation: A Potential Mars Metabolism

    Science.gov (United States)

    Price, Alex; Pearson, Victoria K.; Schwenzer, Susanne P.; Miot, Jennyfer; Olsson-Francis, Karen

    2018-01-01

    This work considers the hypothetical viability of microbial nitrate-dependent Fe2+ oxidation (NDFO) for supporting simple life in the context of the early Mars environment. This draws on knowledge built up over several decades of remote and in situ observation, as well as recent discoveries that have shaped current understanding of early Mars. Our current understanding is that certain early martian environments fulfill several of the key requirements for microbes with NDFO metabolism. First, abundant Fe2+ has been identified on Mars and provides evidence of an accessible electron donor; evidence of anoxia suggests that abiotic Fe2+ oxidation by molecular oxygen would not have interfered and competed with microbial iron metabolism in these environments. Second, nitrate, which can be used by some iron oxidizing microorganisms as an electron acceptor, has also been confirmed in modern aeolian and ancient sediment deposits on Mars. In addition to redox substrates, reservoirs of both organic and inorganic carbon are available for biosynthesis, and geochemical evidence suggests that lacustrine systems during the hydrologically active Noachian period (4.1–3.7 Ga) match the circumneutral pH requirements of nitrate-dependent iron-oxidizing microorganisms. As well as potentially acting as a primary producer in early martian lakes and fluvial systems, the light-independent nature of NDFO suggests that such microbes could have persisted in sub-surface aquifers long after the desiccation of the surface, provided that adequate carbon and nitrates sources were prevalent. Traces of NDFO microorganisms may be preserved in the rock record by biomineralization and cellular encrustation in zones of high Fe2+ concentrations. These processes could produce morphological biosignatures, preserve distinctive Fe-isotope variation patterns, and enhance preservation of biological organic compounds. Such biosignatures could be detectable by future missions to Mars with appropriate

  13. Nitrate-Dependent Iron Oxidation: A Potential Mars Metabolism

    Directory of Open Access Journals (Sweden)

    Alex Price

    2018-03-01

    Full Text Available This work considers the hypothetical viability of microbial nitrate-dependent Fe2+ oxidation (NDFO for supporting simple life in the context of the early Mars environment. This draws on knowledge built up over several decades of remote and in situ observation, as well as recent discoveries that have shaped current understanding of early Mars. Our current understanding is that certain early martian environments fulfill several of the key requirements for microbes with NDFO metabolism. First, abundant Fe2+ has been identified on Mars and provides evidence of an accessible electron donor; evidence of anoxia suggests that abiotic Fe2+ oxidation by molecular oxygen would not have interfered and competed with microbial iron metabolism in these environments. Second, nitrate, which can be used by some iron oxidizing microorganisms as an electron acceptor, has also been confirmed in modern aeolian and ancient sediment deposits on Mars. In addition to redox substrates, reservoirs of both organic and inorganic carbon are available for biosynthesis, and geochemical evidence suggests that lacustrine systems during the hydrologically active Noachian period (4.1–3.7 Ga match the circumneutral pH requirements of nitrate-dependent iron-oxidizing microorganisms. As well as potentially acting as a primary producer in early martian lakes and fluvial systems, the light-independent nature of NDFO suggests that such microbes could have persisted in sub-surface aquifers long after the desiccation of the surface, provided that adequate carbon and nitrates sources were prevalent. Traces of NDFO microorganisms may be preserved in the rock record by biomineralization and cellular encrustation in zones of high Fe2+ concentrations. These processes could produce morphological biosignatures, preserve distinctive Fe-isotope variation patterns, and enhance preservation of biological organic compounds. Such biosignatures could be detectable by future missions to Mars with

  14. Nitrate-Dependent Iron Oxidation: A Potential Mars Metabolism.

    Science.gov (United States)

    Price, Alex; Pearson, Victoria K; Schwenzer, Susanne P; Miot, Jennyfer; Olsson-Francis, Karen

    2018-01-01

    This work considers the hypothetical viability of microbial nitrate-dependent Fe 2+ oxidation (NDFO) for supporting simple life in the context of the early Mars environment. This draws on knowledge built up over several decades of remote and in situ observation, as well as recent discoveries that have shaped current understanding of early Mars. Our current understanding is that certain early martian environments fulfill several of the key requirements for microbes with NDFO metabolism. First, abundant Fe 2+ has been identified on Mars and provides evidence of an accessible electron donor; evidence of anoxia suggests that abiotic Fe 2+ oxidation by molecular oxygen would not have interfered and competed with microbial iron metabolism in these environments. Second, nitrate, which can be used by some iron oxidizing microorganisms as an electron acceptor, has also been confirmed in modern aeolian and ancient sediment deposits on Mars. In addition to redox substrates, reservoirs of both organic and inorganic carbon are available for biosynthesis, and geochemical evidence suggests that lacustrine systems during the hydrologically active Noachian period (4.1-3.7 Ga) match the circumneutral pH requirements of nitrate-dependent iron-oxidizing microorganisms. As well as potentially acting as a primary producer in early martian lakes and fluvial systems, the light-independent nature of NDFO suggests that such microbes could have persisted in sub-surface aquifers long after the desiccation of the surface, provided that adequate carbon and nitrates sources were prevalent. Traces of NDFO microorganisms may be preserved in the rock record by biomineralization and cellular encrustation in zones of high Fe 2+ concentrations. These processes could produce morphological biosignatures, preserve distinctive Fe-isotope variation patterns, and enhance preservation of biological organic compounds. Such biosignatures could be detectable by future missions to Mars with appropriate

  15. Fisiologia e metabolismo do ferro Iron physiology and metabolism

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    Helena Z. W. Grotto

    2010-06-01

    Full Text Available O conhecimento sobre a fisiologia e metabolismo do ferro foi bastante incrementado nos últimos anos. A identificação de alguns genes e as repercussões quando de suas mutações, principalmente as relacionadas ao acúmulo de ferro, auxiliaram no entendimento dos mecanismos regulatórios responsáveis pela manutenção da homeostase desse nutriente essencial para numerosos processos bioquímicos. A função de diversas moléculas já está bem estabelecida, como da transferrina e seu receptor e, nas últimas décadas, novas moléculas têm sido identificadas, como a ferroportina, o transportador de metal divalente e hemojuvelina. Um elegante mecanismo de controle mantém o equilíbrio entre os processos de absorção do ferro, reciclagem, mobilização, utilização e estoque. Alterações no sincronismo desses processos podem causar tanto a deficiência como a sobrecarga de ferro, ambos com importantes repercussões clínicas para o paciente. Nessa minirrevisão serão abordados aspectos relacionados ao metabolismo do ferro e à participação de várias proteínas e mediadores envolvidos. Serão também apresentados os mecanismos regulatórios celular e sistêmico responsáveis pela disponibilidade do ferro em concentrações ideais para a manutenção de sua homeostase.Knowledge of the iron physiology and metabolism has increased greatly over the last few years. The identification of genes and the consequences of mutations, especially those related to the accumulation of iron, have improved the understanding of the regulatory mechanisms responsible for maintaining homeostasis of this essential nutrient in many biochemical processes. The function of several molecules is well established, as in the case of transferrin and its receptor and, in recent decades, new molecules have been identified such as ferroportin, divalent metal transporter, hemojuvelin and hepcidin. An elegant control mechanism maintains the balance between the processes of

  16. Iron deficiency in chronic systolic heart failure(indic study

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    Sunil Verma

    2016-01-01

    Full Text Available Background: Chronic systolic heart failure (HF is characterized by the left ventricular dysfunction, exercise intolerance and is associated with neurohormonal activation that affects several organs such as kidney and skeletal muscle. Anemia is common in HF and may worsen symptoms. Iron deficiency (ID is also common in HF patients with or without anemia. Iron is the key cofactor in oxidative metabolism in skeletal muscle and the Krebs cycle. There is a paucity of data regarding iron metabolism in chronic systolic HF in India. Methods: IroN Deficiency In CHF study (INDIC is an observational study that investigated forty chronic heart failure patients for the presence of ID. Serum ferritin (micrograms per liter, serum iron (micrograms per liter, total iron binding capacity (micrograms per liter, transferring (milligrams per deciliter, and transferrin saturation were measured to assess iron status. Results: There were 67.5% (27/40 patients who had ID with a mean serum ferritin level of 76.4 μg/L. Of the 27 iron deficient patients, 22 (55% had an absolute ID, and 5 had a functional ID. Eight out of 27 of the iron deficient patients were anemic (20% of the total cohort, 30% of the iron deficient patients. Anemia was seen in 6 other patients, which was possibly anemia of chronic disease. There was a trend for more advanced New York Heart Association (NYHA class (NYHA III and NYHA IV patients with ID (37.4% vs. 30.77%, P = 0.697. Conclusion: In our study, ID was very common, affecting more than half of the patients with systolic HF. Absolute ID was the most common cause of ID and patients with ID had a tendency to have advanced NYHA class. Our study also demonstrated that ID can occur in the absence of anemia (iron depletion.

  17. Abnormal brain iron metabolism in Irp2 deficient mice is associated with mild neurological and behavioral impairments.

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    Kimberly B Zumbrennen-Bullough

    Full Text Available Iron Regulatory Protein 2 (Irp2, Ireb2 is a central regulator of cellular iron homeostasis in vertebrates. Two global knockout mouse models have been generated to explore the role of Irp2 in regulating iron metabolism. While both mouse models show that loss of Irp2 results in microcytic anemia and altered body iron distribution, discrepant results have drawn into question the role of Irp2 in regulating brain iron metabolism. One model shows that aged Irp2 deficient mice develop adult-onset progressive neurodegeneration that is associated with axonal degeneration and loss of Purkinje cells in the central nervous system. These mice show iron deposition in white matter tracts and oligodendrocyte soma throughout the brain. A contrasting model of global Irp2 deficiency shows no overt or pathological signs of neurodegeneration or brain iron accumulation, and display only mild motor coordination and balance deficits when challenged by specific tests. Explanations for conflicting findings in the severity of the clinical phenotype, brain iron accumulation and neuronal degeneration remain unclear. Here, we describe an additional mouse model of global Irp2 deficiency. Our aged Irp2-/- mice show marked iron deposition in white matter and in oligodendrocytes while iron content is significantly reduced in neurons. Ferritin and transferrin receptor 1 (TfR1, Tfrc, expression are increased and decreased, respectively, in the brain from Irp2-/- mice. These mice show impairments in locomotion, exploration, motor coordination/balance and nociception when assessed by neurological and behavioral tests, but lack overt signs of neurodegenerative disease. Ultrastructural studies of specific brain regions show no evidence of neurodegeneration. Our data suggest that Irp2 deficiency dysregulates brain iron metabolism causing cellular dysfunction that ultimately leads to mild neurological, behavioral and nociceptive impairments.

  18. Increased cerebral iron uptake in Wilson's disease : A (52)Fe-citrate PET study

    NARCIS (Netherlands)

    Bruehlmeier, M; Leenders, KL; Vontobel, P; Calonder, C; Antonini, A; Weindl, A

    Toxicity of abundant copper is the main cause of brain and liver tissue damage in patients with Wilson's disease (WD). However, there is also evidence of a disturbed iron metabolism in this genetically determined disorder. This PET study was undertaken to assess cerebral iron metabolism in WD

  19. Duodenal Cytochrome b (DCYTB in Iron Metabolism: An Update on Function and Regulation

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    Darius J. R. Lane

    2015-03-01

    Full Text Available Iron and ascorbate are vital cellular constituents in mammalian systems. The bulk-requirement for iron is during erythropoiesis leading to the generation of hemoglobin-containing erythrocytes. Additionally; both iron and ascorbate are required as co-factors in numerous metabolic reactions. Iron homeostasis is controlled at the level of uptake; rather than excretion. Accumulating evidence strongly suggests that in addition to the known ability of dietary ascorbate to enhance non-heme iron absorption in the gut; ascorbate regulates iron homeostasis. The involvement of ascorbate in dietary iron absorption extends beyond the direct chemical reduction of non-heme iron by dietary ascorbate. Among other activities; intra-enterocyte ascorbate appears to be involved in the provision of electrons to a family of trans-membrane redox enzymes; namely those of the cytochrome b561 class. These hemoproteins oxidize a pool of ascorbate on one side of the membrane in order to reduce an electron acceptor (e.g., non-heme iron on the opposite side of the membrane. One member of this family; duodenal cytochrome b (DCYTB; may play an important role in ascorbate-dependent reduction of non-heme iron in the gut prior to uptake by ferrous-iron transporters. This review discusses the emerging relationship between cellular iron homeostasis; the emergent “IRP1-HIF2α axis”; DCYTB and ascorbate in relation to iron metabolism.

  20. Ca-48 metabolism studies

    International Nuclear Information System (INIS)

    Van der Merwe, D.G.

    1987-03-01

    Calcium metabolism has been studied in depth physiologically and is a relatively well-understood element in biochemistry and medicine. There is still only restricted knowledge of the metabolic fate of calcium in normal and abnormal paediatric subjects. The latter is partially owing to inadequate techniques for tracing and modelling calcium pathways in children. The advent of radioactive tracers has unquestionably enhanced medical research and improved the quality of many metabolic studies. The present study was aimed at the development, promotion and justification of a new tracer technique using the stable isotope, calcium-48. The obvious advantages of such a technique are its harmlessness tothe subject, its applicability to both short- and long-term studies as well as its usefulness to the study for which it was originally motivated, viz research defining the actual relationship between a calcium-deficient diet and the occurrence of rickets in rural Black children in South Africa. Exploratory instrumental analyses were performed specifically with serum samples. This proved successful enough to develop a less specific pre-concentration technique which improved the sensitivity and reduces the cost of doing calcium-48 metabolism studies. The results of a simple metabolic study are presented whereby the scope of the technique is demonstrated in a real situation. The possibilities and limitations of double-isotope metabolic studies are discussed, particularly with regard to strontium as the second tracer

  1. Iron-Restricted Diet Affects Brain Ferritin Levels, Dopamine Metabolism and Cellular Prion Protein in a Region-Specific Manner

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    Jessica M. V. Pino

    2017-05-01

    Full Text Available Iron is an essential micronutrient for several physiological functions, including the regulation of dopaminergic neurotransmission. On the other hand, both iron, and dopamine can affect the folding and aggregation of proteins related with neurodegenerative diseases, such as cellular prion protein (PrPC and α-synuclein, suggesting that deregulation of iron homeostasis and the consequential disturbance of dopamine metabolism can be a risk factor for conformational diseases. These proteins, in turn, are known to participate in the regulation of iron and dopamine metabolism. In this study, we evaluated the effects of dietary iron restriction on brain ferritin levels, dopamine metabolism, and the expression levels of PrPC and α-synuclein. To achieve this goal, C57BL/6 mice were fed with iron restricted diet (IR or with normal diet (CTL for 1 month. IR reduced iron and ferritin levels in liver. Ferritin reduction was also observed in the hippocampus. However, in the striatum of IR group, ferritin level was increased, suggesting that under iron-deficient condition, each brain area might acquire distinct capacity to store iron. Increased lipid peroxidation was observed only in hippocampus of IR group, where ferritin level was reduced. IR also generated discrete results regarding dopamine metabolism of distinct brain regions: in striatum, the level of dopamine metabolites (DOPAC and HVA was reduced; in prefrontal cortex, only HVA was increased along with the enhanced MAO-A activity; in hippocampus, no alterations were observed. PrPC levels were increased only in the striatum of IR group, where ferritin level was also increased. PrPC is known to play roles in iron uptake. Thus, the increase of PrPC in striatum of IR group might be related to the increased ferritin level. α-synuclein was not altered in any regions. Abnormal accumulation of ferritin, increased MAO-A activity or lipid peroxidation are molecular features observed in several neurological

  2. Multi-Copper Oxidases and Human Iron Metabolism

    Science.gov (United States)

    Vashchenko, Ganna; MacGillivray, Ross T. A.

    2013-01-01

    Multi-copper oxidases (MCOs) are a small group of enzymes that oxidize their substrate with the concomitant reduction of dioxygen to two water molecules. Generally, multi-copper oxidases are promiscuous with regards to their reducing substrates and are capable of performing various functions in different species. To date, three multi-copper oxidases have been detected in humans—ceruloplasmin, hephaestin and zyklopen. Each of these enzymes has a high specificity towards iron with the resulting ferroxidase activity being associated with ferroportin, the only known iron exporter protein in humans. Ferroportin exports iron as Fe2+, but transferrin, the major iron transporter protein of blood, can bind only Fe3+ effectively. Iron oxidation in enterocytes is mediated mainly by hephaestin thus allowing dietary iron to enter the bloodstream. Zyklopen is involved in iron efflux from placental trophoblasts during iron transfer from mother to fetus. Release of iron from the liver relies on ferroportin and the ferroxidase activity of ceruloplasmin which is found in blood in a soluble form. Ceruloplasmin, hephaestin and zyklopen show distinctive expression patterns and have unique mechanisms for regulating their expression. These features of human multi-copper ferroxidases can serve as a basis for the precise control of iron efflux in different tissues. In this manuscript, we review the biochemical and biological properties of the three human MCOs and discuss their potential roles in human iron homeostasis. PMID:23807651

  3. Diurnal variations in iron concentrations and expression of genes involved in iron absorption and metabolism in pigs.

    Science.gov (United States)

    Zhang, Yiming; Wan, Dan; Zhou, Xihong; Long, Ciming; Wu, Xin; Li, Lan; He, Liuqin; Huang, Pan; Chen, Shuai; Tan, Bie; Yin, Yulong

    2017-09-02

    Diurnal variations in serum iron levels have been well documented in clinical studies, and serum iron is an important diagnostic index for iron-deficiency anemia. However, the underlying mechanism of dynamic iron regulation in response to the circadian rhythm is still unclear. In this study, we investigated daily variations in iron status in the plasma and liver of pigs. The transcripts encoding key factors involved in iron uptake and homeostasis were evaluated. The results showed that iron levels in the plasma and liver exhibited diurnal rhythms. Diurnal variations were also observed in transcript levels of divalent metal transporter 1 (DMT1), membrane-associated ferric reductase 1 (DCYTB), and transferrin receptor (TfR) in the duodenum and jejunum, as well as hepcidin (HAMP) and TfR in the liver. Moreover, the results showed a network in which diurnal variations in systemic iron levels were tightly regulated by hepcidin and Tf/TfR via DCYTB and DMT1. These findings provide new insights into circadian iron homeostasis regulation. The diurnal variations in serum iron levels may also have pathophysiological implications for clinical diagnostics related to iron deficiency anemia in pigs. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. The Study of HFE Genotypes and Its Expression Effect on Iron Status of Iranian Haemochromatosis, Iron Deficiency Anemia Patients, Iron-Taker and Non Iron-Taker Controls.

    Science.gov (United States)

    Beiranvand, Elham; Abediankenari, Saeid; Rostamian, Mosayeb; Beiranvand, Behnoush; Naazeri, Saeed

    2015-01-01

    The role of HFE gene mutations or its expression in regulation of iron metabolism of hereditary haemochromatosis (HH) patients is remained controversial. Therefore here the correlation between two common HFE genotype (p.C282Y, p.H63D) and HFE gene expression with iron status in HH, iron deficiency anemia (IDA) and healthy Iranian participants was studied. For this purpose genotype determination was done by polymerase chain reaction--restriction fragment length polymorphism (PCR-RFLP). Real-Time PCR was applied for evaluation of HFE gene expression. Biochemical parameters and iron consumption were also assessed. Homozygote p.H63D mutation was seen in all HH patients and p.C282Y was not observed in any member of the population. A significant correlation was observed between serum ferritin (SF) level and gender or age of HH patients. p.H63D homozygote was seen to be able to significantly increase SF and transferrin saturation (TS) level without affecting on liver function. Our results also showed that iron consumption affects on TS level increasing. HFE gene expression level of IDA patients was significantly higher than other groups. Also the HFE gene expression was negatively correlated with TS. Finally, the main result of our study showed that loss of HFE function in HH is not derived from its gene expression inhibition and much higher HFE gene expression might lead to IDA. However we propose repeating of the study for more approval of our finding.

  5. Magnetostructural study of iron sucrose

    International Nuclear Information System (INIS)

    Gutierrez, Lucia; Puerto Morales, Maria del; Jose Lazaro, Francisco

    2005-01-01

    Magnetic and structural analyses have been performed on an iron sucrose complex used as a haematinic agent. The system contains two-line ferrihydrite particles of about 5 nm that are superparamagnetic above approximately 50 K. The observed low-temperature magnetic dynamics of this compound is closer to simple models than in the case of other iron-containing drugs for intravenous use like iron dextran

  6. The effect of the hemochromatosis (HFE genotype on lead load and iron metabolism among lead smelter workers.

    Directory of Open Access Journals (Sweden)

    Guangqin Fan

    Full Text Available Both an excess of toxic lead (Pb and an essential iron disorder have been implicated in many diseases and public health problems. Iron metabolism genes, such as the hemochromatosis (HFE gene, have been reported to be modifiers for lead absorption and storage. However, the HFE gene studies among the Asian population with occupationally high lead exposure are lacking.To explore the modifying effects of the HFE genotype (wild-type, H63D variant and C282Y variant on the Pb load and iron metabolism among Asian Pb-workers with high occupational exposure.Seven hundred and seventy-one employees from a lead smelter manufacturing company were tested to determine their Pb intoxication parameters, iron metabolic indexes and identify the HFE genotype. Descriptive and multivariate analyses were conducted.Forty-five H63D variant carriers and no C282Y variant carrier were found among the 771 subjects. Compared with subjects with the wild-type genotype, H63D variant carriers had higher blood lead levels, even after controlling for factors such as age, sex, marriage, education, smoking and lead exposure levels. Multivariate analyses also showed that the H63D genotype modifies the associations between the blood lead levels and the body iron burden/transferrin.No C282Y variant was found in this Asian population. The H63D genotype modified the association between the lead and iron metabolism such that increased blood lead is associated with a higher body iron content or a lower transferrin in the H63D variant. It is indicated that H63D variant carriers may be a potentially highly vulnerable sub-population if they are exposed to high lead levels occupationally.

  7. The effect of the hemochromatosis (HFE) genotype on lead load and iron metabolism among lead smelter workers.

    Science.gov (United States)

    Fan, Guangqin; Du, Guihua; Li, Huijun; Lin, Fen; Sun, Ziyong; Yang, Wei; Feng, Chang; Zhu, Gaochun; Li, Yanshu; Chen, Ying; Jiao, Huan; Zhou, Fankun

    2014-01-01

    Both an excess of toxic lead (Pb) and an essential iron disorder have been implicated in many diseases and public health problems. Iron metabolism genes, such as the hemochromatosis (HFE) gene, have been reported to be modifiers for lead absorption and storage. However, the HFE gene studies among the Asian population with occupationally high lead exposure are lacking. To explore the modifying effects of the HFE genotype (wild-type, H63D variant and C282Y variant) on the Pb load and iron metabolism among Asian Pb-workers with high occupational exposure. Seven hundred and seventy-one employees from a lead smelter manufacturing company were tested to determine their Pb intoxication parameters, iron metabolic indexes and identify the HFE genotype. Descriptive and multivariate analyses were conducted. Forty-five H63D variant carriers and no C282Y variant carrier were found among the 771 subjects. Compared with subjects with the wild-type genotype, H63D variant carriers had higher blood lead levels, even after controlling for factors such as age, sex, marriage, education, smoking and lead exposure levels. Multivariate analyses also showed that the H63D genotype modifies the associations between the blood lead levels and the body iron burden/transferrin. No C282Y variant was found in this Asian population. The H63D genotype modified the association between the lead and iron metabolism such that increased blood lead is associated with a higher body iron content or a lower transferrin in the H63D variant. It is indicated that H63D variant carriers may be a potentially highly vulnerable sub-population if they are exposed to high lead levels occupationally.

  8. Iron in Child Obesity. Relationships with Inflammation and Metabolic Risk Factors

    Directory of Open Access Journals (Sweden)

    Dominique Bouglé

    2013-06-01

    Full Text Available Iron (Fe sequestration is described in overweight and in its associated metabolic complications, i.e., metabolic syndrome (MetS and non-alcoholic liver fatty disease (NAFLD; however, the interactions between Fe, obesity and inflammation make it difficult to recognize the specific role of each of them in the risk of obesity-induced metabolic diseases. Even the usual surrogate marker of Fe stores, ferritin, is influenced by inflammation; therefore, in obese subjects inflammation parameters must be measured together with those of Fe metabolism. This cross-sectional study in obese youth (502 patients; 57% girls: 11.4 ± 3.0 years old (x ± SD; BMI z score 5.5 ± 2.3, multivariate regression analysis showed associations between Fe storage assessed by serum ferritin with risk factors for MetS and NAFLD, assessed by transaminase levels, which were independent of overweight and the acute phase protein fibrinogen. Further studies incorporating the measurement of complementary parameters of Fe metabolism could improve the comprehension of mechanisms involved.

  9. Application of Circuit Simulation Method for Differential Modeling of TIM-2 Iron Uptake and Metabolism in Mouse Kidney Cells

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    Zhijian eXie

    2013-06-01

    Full Text Available Circuit simulation is a powerful methodology to generate differential mathematical models. Due to its highly accurate modelling capability, circuit simulation can be used to investigate interactions between the parts and processes of a cellular system. Circuit simulation has become a core technology for the field of electrical engineering, but its application in biology has not yet been fully realized. As a case study for evaluating the more advanced features of a circuit simulation tool called Advanced Design System (ADS, we collected and modeled laboratory data for iron metabolism in mouse kidney cells for a H ferritin (HFt receptor, T cell immunoglobulin and mucin domain-2 (TIM-2. The internal controlling parameters of TIM-2 associated iron metabolism were extracted and the ratios of iron movement among cellular compartments were quantified by ADS. The differential model processed by circuit simulation demonstrated a capability to identify variables and predict outcomes that could not be readily measured by in vitro experiments. For example, an initial rate of uptake of iron-loaded HFt was 2.17 pmol per million cells. TIM-2 binding probability with iron-loaded HFt was 16.6%. An average of 8.5 minutes was required for the complex of TIM-2 and iron-loaded HFt to form an endosome. The endosome containing HFt lasted roughly 2 hours. At the end of endocytosis, about 28% HFt remained intact and the rest was degraded. Iron released from degraded HFt was in the labile iron pool (LIP and stimulated the generation of endogenous HFt for new storage. Both experimental data and the model showed that TIM-2 was not involved in the process of iron export. The extracted internal controlling parameters successfully captured the complexity of TIM-2 pathway and the use of circuit simulation-based modeling across a wider range of cellular systems is the next step for validating the significance and utility of this method.

  10. Iron metabolism in experimental rickets. Pt. 1. Intestinal absorption of iron in rat rickets

    International Nuclear Information System (INIS)

    Pronicka, E.

    1975-01-01

    Investigations were carried out on iron 59 Fe absorption in rats with experimental rickets. It was found that rats with rickets as compared with controls do not show any significant differences in the degree of iron absorption in fasting state. The percent of absorbed iron increases when it is administered after previous feeding of rats. A greater rise in iron absorption after feeding was shown also by rats with rickets. On the other hand, administration of a shock dose of vitamin D at the time of rickets development causes after 7 days a significant decrease in total iron absorption given to fed rats. An excess of calcium in the diet of rats does not seem to impair directly the absorption of iron. The possibility of the causative effect of vitamin D deficiency on the composition of intestinal contents on changes in the degree of iron absorption observed after feeding of rats with rickets, is discussed. (author)

  11. Iron metabolism in experimental rickets. I. Intestinal absorption of iron in rat rickets

    Energy Technology Data Exchange (ETDEWEB)

    Pronicka, E [Pomorska Akademia Medyczna, Szczecin (Poland)

    1975-01-01

    Investigations were carried out on iron /sup 59/Fe absorption in rats with experimental rickets. It was found that rats with rickets as compared with controls do not show any significant differences in the degree of iron absorption in fasting state. The percent of absorbed iron increases when it is administered after previous feeding of rats. A greater rise in iron absorption after feeding was shown also by rats with rickets. On the other hand, administration of a shock dose of vitamin D at the time of rickets development causes after 7 days a significant decrease in total iron absorption given to fed rats. An excess of calcium in the diet of rats does not seem to impair directly the absorption of iron. The possibility of the causative effect of vitamin D deficiency on the composition of intestinal contents on changes in the degree of iron absorption observed after feeding of rats with rickets, is discussed.

  12. The Effects of Angelica Sinensis Polysaccharide on Tumor Growth and Iron Metabolism by Regulating Hepcidin in Tumor-Bearing Mice

    Directory of Open Access Journals (Sweden)

    Feng Ren

    2018-05-01

    Full Text Available Background/Aims: Iron plays a fundamental role in cell biology and its concentration must be precisely regulated. It is well documented that excess iron burden contributes to the occurrence and progression of cancer. Hepcidin secreted by liver plays an essential role in orchestrating iron metabolism. In the present study, we aimed to investigate the ability of angelica sinensis polysaccharide (ASP to decrease iron burden in tumor-bearing mice and the mechanism of ASP regulation hepcidin expression. Methods: Western blot, RT-PCR, immunohistochemistry (IHC, and enzyme-linked immunosorbent assay (ELISA were used to detect the regulation of hepcidin and related cytokines by ASP. The role of ASP in tumor proliferation was investigated using in vivo assays. Iron depositions and iron concentrations in organs were determined by hematoxylin-eosin (H&E staining and atomic absorption spectrophotometer. Results: We found that ASP could inhibit tumor growth in mice xenografted with 4T1 and H22 cancer cells. In vivo experiments also showed that ASP could potently regulate hepcidin expression in liver and serum and decrease iron burden in liver, spleen and grafted tumors in mouse model. Treatment with ASP in hepatic cell lines reproduced comparable results in decreasing hepcidin as in mouse liver. Furthermore, we found that ASP markedly suppressed the expression of interleukin-6 (IL-6, JAK2, p-STAT3, and p-SMAD1/5/8 in liver, suggesting that JAK/STAT and BMP-SMAD pathways were involved in the regulation of hepcidin expression by ASP. We also found down-regulation of iron-related cytokines in ASP treated mice. Conclusion: The present study provides new evidence that ASP decreases hepcidin expression, which can reduce iron burden and inhibit tumor proliferation. These findings might aid ASP developed as a potential candidate for cancer treatment in patients with iron overload.

  13. Moessbauer study of iron(III) salicylates

    Energy Technology Data Exchange (ETDEWEB)

    Mahesh, K; Sharma, N D; Gupta, D C [Kurukshetra Univ. (India). Dept. of Physics; Puri, D M [Kurukshetra Univ. (India). Dept. of Chemistry

    1979-07-01

    Moessbauer infrared and magnetic studies of different basic salicylates of iron(III) are reported. Comparison of observed isomer shift and quadrupole splitting with the earlier work allows to assign the trinuclear chain structure to the complexes wherein the central iron atom in the chain is considered to be octahedrally coordinated in case of salicylate and 4-aminosalicylate derivatives, and pentacoordinated for the thiosalicylate with the terminal iron atom in tetrahedral symmetry. The Moessbauer parameters and ..mu..sub(eff)-value indicate the high spin state of the central iron atom and low spin state for the terminal ones.

  14. Insights into the Structure and Metabolic Function of Microbes That Shape Pelagic Iron-Rich Aggregates ( Iron Snow )

    Energy Technology Data Exchange (ETDEWEB)

    Lu, S [Friedrich Schiller University Jena, Jena Germany; Chourey, Karuna [ORNL; REICHE, M [Friedrich Schiller University Jena, Jena Germany; Nietzsche, S [Friedrich Schiller University Jena, Jena Germany; Shah, Manesh B [ORNL; Hettich, Robert {Bob} L [ORNL; Kusel, K [Friedrich Schiller University Jena, Jena Germany

    2013-01-01

    Metaproteomics combined with total nucleic acid-based methods aided in deciphering the roles of microorganisms in the formation and transformation of iron-rich macroscopic aggregates (iron snow) formed in the redoxcline of an acidic lignite mine lake. Iron snow had high total bacterial 16S rRNA gene copies, with 2 x 109 copies g (dry wt)-1 in the acidic (pH 3.5) central lake basin and 4 x 1010 copies g (dry wt)-1 in the less acidic (pH 5.5) northern lake basin. Active microbial communities in the central basin were dominated by Alphaproteobacteria (36.6%) and Actinobacteria (21.4%), and by Betaproteobacteria (36.2%) in the northern basin. Microbial Fe-cycling appeared to be the dominant metabolism in the schwertmannite-rich iron snow, because cloning and qPCR assigned up to 61% of active bacteria as Fe-cycling bacteria (FeB). Metaproteomics revealed 70 unique proteins from central basin iron snow and 283 unique proteins from 43 genera from northern basin. Protein identification provided a glimpse into in situ processes, such as primary production, motility, metabolism of acidophilic FeB, and survival strategies of neutrophilic FeB. Expression of carboxysome shell proteins and RubisCO indicated active CO2 fixation by Fe(II) oxidizers. Flagellar proteins from heterotrophs indicated their activity to reach and attach surfaces. Gas vesicle proteins related to CO2-fixing Chlorobium suggested that microbes could influence iron snow sinking. We suggest that iron snow formed by autotrophs in the redoxcline acts as a microbial parachute, since it is colonized by motile heterotrophs during sinking which start to dissolve schwertmannite.

  15. Transferrin Receptor 2 Dependent Alterations of Brain Iron Metabolism Affect Anxiety Circuits in the Mouse

    Science.gov (United States)

    Pellegrino, Rosa Maria; Boda, Enrica; Montarolo, Francesca; Boero, Martina; Mezzanotte, Mariarosa; Saglio, Giuseppe; Buffo, Annalisa; Roetto, Antonella

    2016-01-01

    The Transferrin Receptor 2 (Tfr2) modulates systemic iron metabolism through the regulation of iron regulator Hepcidin (Hepc) and Tfr2 inactivation causes systemic iron overload. Based on data demonstrating Tfr2 expression in brain, we analysed Tfr2-KO mice in order to examine the molecular, histological and behavioural consequences of Tfr2 silencing in this tissue. Tfr2 abrogation caused an accumulation of iron in specific districts in the nervous tissue that was not accompanied by a brain Hepc response. Moreover, Tfr2-KO mice presented a selective overactivation of neurons in the limbic circuit and the emergence of an anxious-like behaviour. Furthermore, microglial cells showed a particular sensitivity to iron perturbation. We conclude that Tfr2 is a key regulator of brain iron homeostasis and propose a role for Tfr2 alpha in the regulation of anxiety circuits. PMID:27477597

  16. Paving a Path to Understanding Metabolic Responses to Iron Bioavailability: Global Proteomic Analysis of Crocosphaera watsonii

    Science.gov (United States)

    Gauglitz, J.; McIlvin, M. R.; Moran, D. M.; Waterbury, J. B.; Saito, M. A.

    2016-02-01

    Marine diazotrophic cyanobacteria provide a key source of new nitrogen into the oceans and are important contributors to primary production. The geographic distribution of these cyanobacteria is impacted by available iron and phosphorus as well as environmental conditions such as temperature, however available iron concentrations are thought to be particularly critical due to the high demand for iron in cellular processes. Iron bioavailability and microorganismal adaptations to low iron environments may thus play a key role in dictating community structure, however the mechanisms by which cyanobacteria acquire iron and regulate its uptake are not well defined. In this study, the unicellular diazotroph, Crocosphaera watsonii WH8501, was acclimated to a range of bioavailable iron concentrations (from 0.001nM to 8.13nM Fe') using trace metal clean culturing techniques and the proteomes were analyzed by LC/MS-MS. Physiological and proteomic data indicate three distinct phenotypic ranges: iron-replete, iron-limited, and iron-starved. Trends in photosynthetic, carbon fixation and iron storage proteins across the iron gradient indicate that the C. watsonii proteome responds directly to iron availability. Further analysis of relative protein expression, which describes the physiological state of the cell, will lead to insights into how C. watsonii is able to adapt to iron-limited conditions and the resulting biogeochemical implications will be discussed.

  17. Hemojuvelin: a supposed role in iron metabolism one year after its discovery.

    Science.gov (United States)

    Celec, Peter

    2005-07-01

    The discovery of hemojuvelin and its association with juvenile hemochromatosis are important not only for the diagnostics of this rare severe disease but also for the understanding of the complex mechanism of iron metabolism regulation. Currently, the physiological role of hemojuvelin is obscure. Recent experimental and clinical studies indicate that hemojuvelin will probably be a regulator of hepcidin, similar to HFE and transferrin receptor 2. However, in contrast to transferrin receptor 2, which is relevant in the hepcidin response to changes in transferrin saturation, HFE and especially hemojuvelin seem to be involved in the inflammation-induced hepcidin expression. Hepcidin, generally accepted as a hormone targeting enterocytes and macrophages, decreases iron absorption from the intestinal lumen and iron release from phagocytes. This mechanism explains the central role of hepcidin and, indirectly, its regulator, hemojuvelin, in the pathogenesis of hemochromatosis but also in anemia of chronic disease. Further basic and clinical research is needed to uncover the details of hemojuvelin pathophysiology required for potential pharmacological interventions.

  18. Iron effect on the fermentative metabolism of Clostridium acetobutylicum ATCC 824 using cheese whey as substrate

    Directory of Open Access Journals (Sweden)

    Victoria Rosalía Durán-Padilla

    2014-12-01

    Full Text Available Butanol is considered a superior liquid fuel that can replace gasoline in internal combustion engines. It is produced by acetone-butanol-ethanol (ABE fermentation using various species of solventogenic clostridia. Performance of ABE fermentation process is severely limited mostly by high cost of substrate, substrate inhibition and low solvent tolerance; leading to low product concentrations, low productivity, low yield, and difficulty in controlling culture metabolism. In order to decrease the cost per substrate and exploit a waste generated by dairy industry, this study proposes using cheese whey as substrate for ABE fermentation. It was observed that the addition of an iron source was strictly necessary for the cheese whey to be a viable substrate because this metal is needed to produce ferredoxin, a key protein in the fermentative metabolism of Clostridium acetobutylicum serving as a temporary electron acceptor. Lack of iron in the cheese whey impedes ferredoxin synthesis and therefore, restricts pyruvate-ferredoxin oxidoreductase activity leading to the production of lactic acid instead of acetone, butanol and ethanol. Moreover, the addition of FeSO4 notably improved ABE production performance by increasing butanol content (7.13 ± 1.53 g/L by 65% compared to that of FeCl3 (4.32 ± 0.94 g/L under the same fermentation conditions.

  19. Effect of Nordic Walking training on iron metabolism in elderly women

    Directory of Open Access Journals (Sweden)

    Kortas J

    2015-11-01

    Full Text Available Jakub Kortas,1 Katarzyna Prusik,2 Damian Flis,3 Krzysztof Prusik,1 Ewa Ziemann,4 Neil Leaver,5 Jedrzej Antosiewicz6 1Department of Recreation and Tourism, Gdansk University of Physical Education and Sport, Gdansk, Poland; 2Department of Biomedical Basis of Health, Gdansk University of Physical Education and Sport, Gdansk, Poland; 3Department of Bioenergetics and Physiology of Exercise, Medical University of Gdansk, Gdansk, Poland; 4Department of Physiology and Pharmacology, Gdansk University of Physical Education and Sport, Gdansk, Poland; 5The Immunosuppression monitoring service (IMS Laboratory, Royal Brompton & Harefield NHS Foundation Trust, Heart Science Centre, Harefield Hospital, Harefield, UK; 6Department of Biochemistry, Gdansk University of Physical Education and Sport, Gdansk, Poland Background: Despite several, well-documented pro-healthy effects of regular physical training, its influence on body iron stores in elderly people remains unknown. At the same time, body iron accumulation is associated with high risk of different morbidities.Purpose: We hypothesized that Nordic Walking training would result in pro-healthy changes in an elderly group of subjects by reducing body iron stores via shifts in iron metabolism-regulating proteins.Methods: Thirty-seven women aged 67.7±5.3 years participated in this study. They underwent 32 weeks of training, 1-hour sessions three times a week, between October 2012 and May 2013. Fitness level, blood morphology, CRP, vitamin D, ferritin, hepcidin, and soluble Hjv were assessed before and after the training.Results: The training program caused a significant decrease in ferritin, which serves as a good marker of body iron stores. Simultaneously, the physical cardiorespiratory fitness had improved. Furthermore, blood hepcidin was positively correlated with the ferritin concentration after the training. The concentration of blood CRP dropped, but the change was nonsignificant. The applied training

  20. Catalytic function of the mycobacterial binuclear iron monooxygenase in acetone metabolism.

    Science.gov (United States)

    Furuya, Toshiki; Nakao, Tomomi; Kino, Kuniki

    2015-10-01

    Mycobacteria such as Mycobacterium smegmatis strain mc(2)155 and Mycobacterium goodii strain 12523 are able to grow on acetone and use it as a source of carbon and energy. We previously demonstrated by gene deletion analysis that the mimABCD gene cluster, which encodes a binuclear iron monooxygenase, plays an essential role in acetone metabolism in these mycobacteria. In the present study, we determined the catalytic function of MimABCD in acetone metabolism. Whole-cell assays were performed using Escherichia coli cells expressing the MimABCD complex. When the recombinant E. coli cells were incubated with acetone, a product was detected by gas chromatography (GC) analysis. Based on the retention time and the gas chromatography-mass spectrometry (GC-MS) spectrum, the reaction product was identified as acetol (hydroxyacetone). The recombinant E. coli cells produced 1.02 mM of acetol from acetone within 24 h. Furthermore, we demonstrated that MimABCD also was able to convert methylethylketone (2-butanone) to 1-hydroxy-2-butanone. Although it has long been known that microorganisms such as mycobacteria metabolize acetone via acetol, this study provides the first biochemical evidence for the existence of a microbial enzyme that catalyses the conversion of acetone to acetol. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  1. Electron Spectroscopy Studies of Iron, Iron Sulfides and Supported Iron Surfaces: Chemisorption of Simple Gases.

    Science.gov (United States)

    Lee, Yiu Chung

    EELS was used to investigate the chemisorption of oxygen and carbon on iron. The EELS spectra of oxidized iron show characteristic features with strong enhancement of the interband transitions involving the Fe 3d band (4.6 and 7.5 eV) and moderate enhancement of the M(,2,3) transition doublet (54.4 and 58.2 eV). The changes in the electron energy loss structures with an overlayer of graphitic or carbidic carbon were investigated. The adsorption and growth of iron on Ni(100) has been studied using the combined techniques of LEED and EELS. Initially iron grows by a layer-by-layer mechanism for the first few layers. High iron coverages result in the observation of complex LEED patterns with satellites around the main (1 x 1) diffraction sports. This is due to the formation of b.c.c. Fe(110) crystallites arranged in domains with different orientations. EELS studies show the presence of three stages in the growth of iron on Ni(100): low-coverage, film-like and bulk-like. Auger and EELS were used to study the iron sulfide (FeS(,2), Fe(,7)S(,8) and FeS) surfaces. A characteristic M(,2,3) VV Auger doublet with a separation of 5.0 eV was observed on the sulfides. An assignment of the electron energy loss peaks was made based on the energy dependence of the loss peaks and previous photoemission results. The effect of argon ion bombardment was studied. Peaks with strong iron and sulfur character were observed. Heating the damaged sulfides results in reconstruction of the sulfide surfaces. The reactions of the sulfides with simple gases, such as H(,2), CO, CH(,4), C(,2)H(,4), NH(,3) and O(,2) were also studied. Using XPS, the chemisorption of SO(,2) on CaO(100) has been studied. The chemical state of sulfur has been identified as that of sulfate. The kinetics of SO(,2) chemisorption on CaO are discussed. The binding states of Fe and Na on CaO were determined to be Fe('2+) and Na('+) respectively. At low Fe or Na coverages (< 0.5 ML), there is a large increase in the rate of

  2. Quantification of body iron and iron absorption in the REDS-II Donor Iron Status Evaluation (RISE) study.

    Science.gov (United States)

    Kiss, Joseph E; Birch, Rebecca J; Steele, Whitney R; Wright, David J; Cable, Ritchard G

    2017-07-01

    Repeated blood donation alters the iron balance of blood donors. We quantified these effects by analyzing changes in body iron as well as calculating iron absorbed per day for donors enrolled in a prospective study. For 1308 donors who completed a final study visit, we calculated total body iron at the enrollment and final visits and the change in total body iron over the course of the study. Taking into account iron lost from blood donations during the study and obligate losses, we also calculated the average amount of iron absorbed per day. First-time/reactivated donors at enrollment had iron stores comparable to previous general population estimates. Repeat donors had greater donation intensity and greater mean iron losses than first-time/reactivated donors, yet they had little change in total body iron over the study period, whereas first-time/reactivated donors had an average 35% drop. There was higher estimated iron absorption in the repeat donors (men: 4.49 mg/day [95% confidence interval [CI], 4.41-4.58 mg/day]; women: 3.75 mg/day [95% CI, 3.67-3.84 mg/day]) compared with estimated iron absorption in first-time/reactivated donors (men: 2.89 mg/day [95% CI, 2.75-3.04 mg/day]; women: 2.76 mg/day [95% CI, 2.64-2.87 mg/day]). The threshold for negative estimated iron stores (below "0" mg/kg stores) was correlated with the development of anemia at a plasma ferritin value of 10 ng/mL. These analyses provide quantitative data on changes in estimated total body iron for a broad spectrum of blood donors. In contrast to using ferritin alone, this model allows assessment of the iron content of red blood cells and the degree of both iron surplus and depletion over time. © 2017 AABB.

  3. Proteomic analysis reveals that iron availability alters the metabolic status of the pathogenic fungus Paracoccidioides brasiliensis.

    Directory of Open Access Journals (Sweden)

    Ana F A Parente

    Full Text Available Paracoccidioides brasiliensis is a thermodimorphic fungus and the causative agent of paracoccidioidomycosis (PCM. The ability of P. brasiliensis to uptake nutrients is fundamental for growth, but a reduction in the availability of iron and other nutrients is a host defense mechanism many pathogenic fungi must overcome. Thus, fungal mechanisms that scavenge iron from host may contribute to P. brasiliensis virulence. In order to better understand how P. brasiliensis adapts to iron starvation in the host we compared the two-dimensional (2D gel protein profile of yeast cells during iron starvation to that of iron rich condition. Protein spots were selected for comparative analysis based on the protein staining intensity as determined by image analysis. A total of 1752 protein spots were selected for comparison, and a total of 274 out of the 1752 protein spots were determined to have changed significantly in abundance due to iron depletion. Ninety six of the 274 proteins were grouped into the following functional categories; energy, metabolism, cell rescue, virulence, cell cycle, protein synthesis, protein fate, transcription, cellular communication, and cell fate. A correlation between protein and transcript levels was also discovered using quantitative RT-PCR analysis from RNA obtained from P. brasiliensis under iron restricting conditions and from yeast cells isolated from infected mouse spleens. In addition, western blot analysis and enzyme activity assays validated the differential regulation of proteins identified by 2-D gel analysis. We observed an increase in glycolytic pathway protein regulation while tricarboxylic acid cycle, glyoxylate and methylcitrate cycles, and electron transport chain proteins decreased in abundance under iron limiting conditions. These data suggest a remodeling of P. brasiliensis metabolism by prioritizing iron independent pathways.

  4. Deciphering Fur transcriptional regulatory network highlights its complex role beyond iron metabolism in Escherichia coli

    DEFF Research Database (Denmark)

    Seo, Sang Woo; Kim, Donghyuk; Latif, Haythem

    2014-01-01

    The ferric uptake regulator (Fur) plays a critical role in the transcriptional regulation of iron metabolism. However, the full regulatory potential of Fur remains undefined. Here we comprehensively reconstruct the Fur transcriptional regulatory network in Escherichia coli K-12 MG1655 in response...

  5. A report on the metabolism of iron in goats artificially infected with Haemonchus contortus

    International Nuclear Information System (INIS)

    Perpuse, W.G.; Yumul, B.Y.; Anden, A.

    1976-03-01

    The determination of iron metabolism in goats artificially infected with N. contortus using tracer method has been conducted. Radioferric chloride ( 59 Fe) was given orally and intravenously and the distribution and utilization in goats were determined. Results showed that anemic goats have a higher absorption rate compared to non-anemic goats. Of all the organs examined the bone marrow showed the highest activity

  6. Toll- like receptors expressed on embryonic macrophages couple inflammatory signals to iron metabolism during early ontogenesis

    Czech Academy of Sciences Publication Activity Database

    Balounová, Jana; Vavrochová, Tereza; Benešová, Martina; Ballek, Ondřej; Kolář, Michal; Filipp, Dominik

    2014-01-01

    Roč. 44, č. 5 (2014), s. 1491-1502 ISSN 0014-2980 R&D Projects: GA AV ČR IAA500520707 Institutional support: RVO:68378050 Keywords : Embryo nic macrophages * Ferroportin * Gene expression microarray * Iron metabolism * TLR stimulation Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.034, year: 2014

  7. Toll- like receptors expressed on embryonic macrophages couple inflammatory signals to iron metabolism during early ontogenesis

    Czech Academy of Sciences Publication Activity Database

    Balounová, Jana; Vavrochová, Tereza; Benešová, Martina; Ballek, Ondřej; Kolář, Michal; Filipp, Dominik

    2014-01-01

    Roč. 44, č. 5 (2014), s. 1491-1502 ISSN 0014-2980 R&D Projects: GA AV ČR IAA500520707 Institutional support: RVO:68378050 Keywords : Embryonic macrophages * Ferroportin * Gene expression microarray * Iron metabolism * TLR stimulation Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.034, year: 2014

  8. Crosstalk between inflammation, iron metabolism and endothelial function in Behçet's disease.

    Science.gov (United States)

    Oliveira, Rita; Napoleão, Patricia; Banha, João; Paixão, Eleonora; Bettencourt, Andreia; da Silva, Berta Martins; Pereira, Dina; Barcelos, Filipe; Teixeira, Ana; Patto, José Vaz; Viegas-Crespo, Ana Maria; Costa, Luciana

    2014-01-01

    Behçet's disease (BD) is a rare chronic vasculitis of unclear etiology. It has been suggested that inflammatory response has an important role in BD pathophysiology. Herein, we aimed to study the interplay between inflammation, iron metabolism and endothelial function in BD and search for its putative association with disease activity. Twenty five patients clinically diagnosed with BD were selected and twenty four healthy age-sex matched individuals participated as controls. Results showed an increase of total number of circulating white blood cells and neutrophils, serum transferrin, total iron binding capacity, mieloperoxidase (MPO), ceruloplasmin (Cp), C reactive protein, β2 microglobulin and Cp surface expression in peripheral blood monocytes in BD patients comparatively to healthy individuals (p < 0,05). Of notice, the alterations observed were associated to disease activity status. No significant differences between the two groups were found in serum nitric oxide concentration. The results obtained suggest an important contribution from innate immunity in the pathogenesis of this disease. In particular, surface expression of leukocyte-derived Cp may constitute a new and relevant biomarker to understand BD etiology.

  9. Serum Hepcidin and Soluble Transferrin Receptor in the Assessment of Iron Metabolism in Children on a Vegetarian Diet.

    Science.gov (United States)

    Ambroszkiewicz, Jadwiga; Klemarczyk, Witold; Mazur, Joanna; Gajewska, Joanna; Rowicka, Grażyna; Strucińska, Małgorzata; Chełchowska, Magdalena

    2017-12-01

    The aim of this study was to assess the effect of vegetarian diet on iron metabolism parameters paying special attention to serum hepcidin and soluble transferrin receptor (sTfR) concentrations in 43 prepubertal children (age range 4.5-9.0 years) on vegetarian and in 46 children on omnivorous diets. There were no significant differences according to age, weight, height, and body mass index (BMI) between vegetarian and omnivorous children. Vegetarians had similar intake of iron and vitamin B 12 and a significantly higher intake of vitamin C (p vegetarians. Hematologic parameters and serum iron concentrations were within the reference range in both groups of children. Serum transferrin levels were similar in all subjects; however, ferritin concentrations were significantly (p vegetarians than in omnivores. In children on a vegetarian diet, median hepcidin levels were lower (p vegetarians. We did not find significant associations with concentration of sTfR and selected biochemical, anthropometric, and dietary parameters in any of the studied groups of children. As hematologic parameters and iron concentrations in vegetarians and omnivores were comparable and ferritin level was lower in vegetarians, we suggest that inclusion of novel markers, in particular sTfR (not cofounded by inflammation) and hepcidin, can better detect subclinical iron deficiency in children following vegetarian diets.

  10. Nuevos conocimientos sobre el metabolismo del hierro New knowledge of iron metabolism

    Directory of Open Access Journals (Sweden)

    Mariela Forrellat Barrios

    2005-12-01

    Full Text Available El hierro es un mineral de elevada importancia para el organismo y su regulación requiere de una red molecular compleja. Hasta hace unos años solo se conocían 3 proteínas que intervenían en el metabolismo del hierro, pero en la última década, se han descubierto de forma secuencial, y a partir del estudio de algunas enfermedades genéticas como la hemocromatosis hereditaria, nuevas proteínas que participan en la homeostasia del hierro y que están implicadas en su transporte, absorción, reciclaje y balance en el organismo. La identificación y aislamiento de estas proteínas lleva inevitablemente a la modificación de los modelos clásicos de regulación de la homeostasia de este importante mineral. En este trabajo se realizó una revisión de los elementos esenciales conocidos hasta la actualidad de cada una de estas nuevas proteínas y la interacción entre ellasIron is a very important mineral for the organism and its regulation requires a complex molecular network. Only 3 proteins that took part in iron metabolism were known a few years ago, but in the last decade, new proteins that participate in iron homeostasis and that are involved in its transportation, absorption, recycling and balance in the organism have been discovered in a sequential way, starting from the study of some genetical diseases, such as hereditary hemochromatosis. The identification and isolation of these proteins lead inevitably to the modification of the classical models of regulation of the homeostasis of this powerful mineral. A review of the esential elements known up to now of each of these new proteins and the interaction among them was made in this paper

  11. Dysregulation of Iron Metabolism in Cholangiocarcinoma Stem-like Cells

    DEFF Research Database (Denmark)

    Raggi, Chiara; Gammella, Elena; Correnti, Margherita

    2017-01-01

    Cholangiocarcinoma (CCA) is a devastating liver tumour arising from malignant transformation of bile duct epithelial cells. Cancer stem cells (CSC) are a subset of tumour cells endowed with stem-like properties, which play a role in tumour initiation, recurrence and metastasis. In appropriate con...... compartment as a novel metabolic factor involved in CCA growth, may have implications for a better therapeutic approach....

  12. Estrogen-induced disruption of intracellular iron metabolism leads to oxidative stress, membrane damage, and cell cycle arrest in MCF-7 cells.

    Science.gov (United States)

    Bajbouj, Khuloud; Shafarin, Jasmin; Abdalla, Maher Y; Ahmad, Iman M; Hamad, Mawieh

    2017-10-01

    It is well established that several forms of cancer associate with significant iron overload. Recent studies have suggested that estrogen (E2) disrupts intracellular iron homeostasis by reducing hepcidin synthesis and maintaining ferroportin integrity. Here, the ability of E2 to alter intracellular iron status and cell growth potential was investigated in MCF-7 cells treated with increasing concentrations of E2. Treated cells were assessed for intracellular iron status, the expression of key proteins involved in iron metabolism, oxidative stress, cell survival, growth, and apoptosis. E2 treatment resulted in a significant reduction in hepcidin expression and a significant increase in hypoxia-inducible factor 1 alpha, ferroportin, transferrin receptor, and ferritin expression; a transient decrease in labile iron pool; and a significant increase in total intracellular iron content mainly at 20 nM/48 h E2 dose. Treated cells also showed increased total glutathione and oxidized glutathione levels, increased superoxide dismutase activity, and increased hemoxygenase 1 expression. Treatment with E2 at 20 nM for 48 h resulted in a significant reduction in cell growth (0.35/1 migration rate) and decreased cell survival (iron metabolism and precipitates adverse effects concerning cell viability, membrane integrity, and growth potential.

  13. Metabolic alterations, HFE gene mutations and atherogenic lipoprotein modifications in patients with primary iron overload.

    Science.gov (United States)

    Meroño, Tomás; Brites, Fernando; Dauteuille, Carolane; Lhomme, Marie; Menafra, Martín; Arteaga, Alejandra; Castro, Marcelo; Saez, María Soledad; Ballerga, Esteban González; Sorroche, Patricia; Rey, Jorge; Lesnik, Philippe; Sordá, Juan Andrés; Chapman, M John; Kontush, Anatol; Daruich, Jorge

    2015-05-01

    Iron overload (IO) has been associated with glucose metabolism alterations and increased risk of cardiovascular disease (CVD). Primary IO is associated with mutations in the HFE gene. To which extent HFE gene mutations and metabolic alterations contribute to the presence of atherogenic lipoprotein modifications in primary IO remains undetermined. The present study aimed to assess small, dense low-density lipoprotein (LDL) levels, chemical composition of LDL and high-density lipoprotein (HDL) particles, and HDL functionality in IO patients. Eighteen male patients with primary IO and 16 sex- and age-matched controls were recruited. HFE mutations (C282Y, H63D and S65C), measures of insulin sensitivity and secretion (calculated from the oral glucose tolerance test), chemical composition and distribution profile of LDL and HDL subfractions (isolated by gradient density ultracentrifugation) and HDL functionality (as cholesterol efflux and antioxidative activity) were studied. IO patients compared with controls exhibited insulin resistance (HOMA-IR (homoeostasis model assessment-estimated insulin resistance): +93%, PHFE genotypes. C282Y homozygotes (n=7) presented a reduced β-cell function and insulin secretion compared with non-C282Y patients (n=11) (-58% and -73%, respectively, PHFE gene mutations are involved in the presence of atherogenic lipoprotein modifications in primary IO. To what extent such alterations could account for an increase in CVD risk remains to be determined.

  14. Serotonergic dysfunctions and abnormal iron metabolism: Relevant to mental fatigue of Parkinson disease.

    Science.gov (United States)

    Zuo, Li-Jun; Yu, Shu-Yang; Hu, Yang; Wang, Fang; Piao, Ying-Shan; Lian, Teng-Hong; Yu, Qiu-Jin; Wang, Rui-Dan; Li, Li-Xia; Guo, Peng; Du, Yang; Zhu, Rong-Yan; Jin, Zhao; Wang, Ya-Jie; Wang, Xiao-Min; Chan, Piu; Chen, Sheng-Di; Wang, Yong-Jun; Zhang, Wei

    2016-12-21

    Fatigue is a very common non-motor symptom in Parkinson disease (PD) patients. It included physical fatigue and mental fatigue. The potential mechanisms of mental fatigue involving serotonergic dysfunction and abnormal iron metabolism are still unknown. Therefore, we evaluated the fatigue symptoms, classified PD patients into fatigue group and non-fatigue group, and detected the levels of serotonin, iron and related proteins in CSF and serum. In CSF, 5-HT level is significantly decreased and the levels of iron and transferrin are dramatically increased in fatigue group. In fatigue group, mental fatigue score is negatively correlated with 5-HT level in CSF, and positively correlated with the scores of depression and excessive daytime sleepiness, and disease duration, also, mental fatigue is positively correlated with the levels of iron and transferrin in CSF. Transferrin level is negatively correlated with 5-HT level in CSF. In serum, the levels of 5-HT and transferrin are markedly decreased in fatigue group; mental fatigue score exhibits a negative correlation with 5-HT level. Thus serotonin dysfunction in both central and peripheral systems may be correlated with mental fatigue through abnormal iron metabolism. Depression, excessive daytime sleepiness and disease duration were the risk factors for mental fatigue of PD.

  15. Insights into the iron and sulfur energetic metabolism of Acidithiobacillus ferrooxidans by microarray transcriptome profiling

    Energy Technology Data Exchange (ETDEWEB)

    R. Quatrini; C. Appia-Ayme; Y. Denis; J. Ratouchniak; F. Veloso; J. Valdes; C. Lefimil; S. Silver; F. Roberto; O. Orellana; F. Denizot; E. Jedlicki; D. Holmes; V. Bonnefoy

    2006-09-01

    Acidithiobacillus ferrooxidans is a well known acidophilic, chemolithoautotrophic, Gram negative, bacterium involved in bioleaching and acid mine drainage. In aerobic conditions, it gains energy mainly from the oxidation of ferrous iron and/or reduced sulfur compounds present in ores. After initial oxidation of the substrate, electrons from ferrous iron or sulfur enter respiratory chains and are transported through several redox proteins to oxygen. However, the oxidation of ferrous iron and reduced sulfur compounds has also to provide electrons for the reduction of NAD(P) that is subsequently required for many metabolic processes including CO2 fixation. To help to unravel the enzymatic pathways and the electron transfer chains involved in these processes, a genome-wide microarray transcript profiling analysis was carried out. Oligonucleotides corresponding to approximately 3000 genes of the A. ferrooxidans type strain ATCC23270 were spotted onto glass-slides and hybridized with cDNA retrotranscribed from RNA extracted from ferrous iron and sulfur grown cells. The genes which are preferentially transcribed in ferrous iron conditions and those preferentially transcribed in sulfur conditions were analyzed. The expression of a substantial number of these genes has been validated by real-time PCR, Northern blot hybridization and/or immunodetection analysis. Our results support and extend certain models of iron and sulfur oxidation and highlight previous observations regarding the possible presence of alternate electron pathways. Our findings also suggest ways in which iron and sulfur oxidation may be co-ordinately regulated. An accompanying paper (Appia-Ayme et al.) describes results pertaining to other metabolic functions.

  16. Investigation on Abnormal Iron Metabolism and Related Inflammation in Parkinson Disease Patients with Probable RBD

    Science.gov (United States)

    Hu, Yang; Yu, Shu-Yang; Zuo, Li-Jun; Piao, Ying-Shan; Cao, Chen-Jie; Wang, Fang; Chen, Ze-Jie; Du, Yang; Lian, Teng-Hong; Liu, Gai-Fen; Wang, Ya-Jie; Chan, Piu; Chen, Sheng-Di; Wang, Xiao-Min; Zhang, Wei

    2015-01-01

    Objective To investigate potential mechanisms involving abnormal iron metabolism and related inflammation in Parkinson disease (PD) patients with probable rapid eye movement sleep behavior disorder (PRBD). Methods Total 210 PD patients and 31 controls were consecutively recruited. PD patients were evaluated by RBD Screening Questionnaire (RBDSQ) and classified into PRBD and probable no RBD (NPRBD) groups. Demographics information were recorded and clinical symptoms were evaluated by series of rating scales. Levels of iron and related proteins and inflammatory factors in cerebrospinal fluid (CSF) and serum were detected. Comparisons among control, NPRBD and PRBD groups and correlation analyses between RBDSQ score and levels of above factors were performed. Results (1)The frequency of PRBD in PD patients is 31.90%. (2)PRBD group has longer disease duration, more advanced disease stage, severer motor symptoms and more non-motor symptoms than NPRBD group. (3)In CSF, levels of iron, transferrin, NO and IL–1β in PRBD group are prominently increased. RBDSQ score is positively correlated with the levels of iron, transferrin, NO and IL–1β in PD group. Iron level is positively correlated with the levels of NO and IL–1β in PD group. (4)In serum, transferrin level is prominently decreased in PRBD group. PGE2 level in PRBD group is drastically enhanced. RBDSQ score exhibits a positive correlation with PGE2 level in PD group. Conclusions PRBD is common in PD patients. PRBD group has severer motor symptoms and more non-motor symptoms. Excessive iron in brain resulted from abnormal iron metabolism in central and peripheral systems is correlated with PRBD through neuroinflammation. PMID:26431210

  17. Iron

    Science.gov (United States)

    Iron is a mineral that our bodies need for many functions. For example, iron is part of hemoglobin, a protein which carries ... It helps our muscles store and use oxygen. Iron is also part of many other proteins and ...

  18. Solidification of cast iron - A study on the effect of microalloy elements on cast iron

    DEFF Research Database (Denmark)

    Moumeni, Elham

    The present thesis deals with the heat transfer and solidification of ductile and microalloyed grey cast iron. Heterogeneous nucleation of nodular graphite at inclusions in ductile iron during eutectic solidification has been investigated. A series of ductile iron samples with two different...... of the austenite, in the last region to solidify. The superfine graphite which forms in this type of irons is short (10-20µm) and stubby. The microstructure of this kind of graphite flakes in titanium alloyed cast iron is studied using electron microscopy techniques. The methods to prepare samples of cast iron...... for comprehensive transmission electron microscopy of graphite and the surrounding iron matrix have been developed and explained. Dual beam microscopes are used for sample preparation. A TEM study has been carried out on graphite flakes in grey cast iron using selected area electron diffraction (SAED). Based...

  19. Experimental and theoretical study of heterogeneous iron precipitation in silicon

    OpenAIRE

    Haarahiltunen, Antti; Väinölä, Hele; Anttila, O.; Yli-Koski, Marko

    2007-01-01

    Heterogeneous iron precipitation in silicon was studied experimentally by measuring the gettering efficiency of oxide precipitate density of 1×10exp10cm−3. The wafers were contaminated with varying iron concentrations, and the gettering efficiency was studied using isothermal annealing in the temperature range from 300 to 780°C. It was found that iron precipitation obeys the so called s-curve behavior: if iron precipitation occurs, nearly all iron is gettered. For example, after 30 min anneal...

  20. An iron-57 Moessbauer spectroscopic study of titania-supported iron- and iron-iridium catalysts

    International Nuclear Information System (INIS)

    Berry, F.J.; Jobson, S.

    1992-01-01

    57 Fe Moessbauer spectroscopy shows that titania-supported iron is reduced by treatment in hydrogen at significantly lower temperatures than corresponding silica- and alumina-supported catalysts. The metallic iron formed under hydrogen at 600deg C is partially converted to carbide by treatment in carbon monoxide and hydrogen. In contrast to its alumina- and silica-supported counterparts, the remainder of the titania-supported iron is unchanged by this gaseous mixture. The 57 Fe Moessbauer spectra of EXAFS show that iron and iridium in the titania-supported iron-iridium catalysts are reduced in hydrogen at even lower temperatures and, after treatment at 600deg C, are predominantly present as the iron-iridium alloy. The treatment of these reduced catalysts in carbon monoxide and hydrogen is shown by Moessbauer spectroscopy and EXAFS to induce the segregation of iron from the iron-iridium alloy and its conversion to iron oxide. (orig.)

  1. Effect of diet composition and mixture of selected food additives on the erythrocytic system and iron metabolism in peripheral blood of male rats.

    Science.gov (United States)

    Sadowska, Joanna; Kuchlewska, Magdalena

    2011-01-01

    Metabolic processes of food additives which are "exogenous xenobiotics" are catalysed, primarily, by enzymes located in microsomes of hepatocytes affiliated to P-450 cytochrome superfamily, containing iron. The aim of the study was to investigate the effect of diet composition and selected food additives on the erythrocyte system and iron metabolism in peripheral blood of male rats. The experiment was carried out on 30 male rats sorted into three equinumerous groups. For drinking animals received pure, settled tap water, animals from group III were receiving additionally an aqueous solution of sodium (nitrate), potassium nitrite, benzoic acid, sorbic acid and monosodium glutamate. Ascertained a significant effect of changes in diet composition on the increase in hematocrit marker value and the count of red blood cells in blood of animals examined. Used food additives diminished hemoglobin concentration, hematocrit value and red blood cell count, diminishing also iron concentration in serum, the total iron binding capacity and transferrin saturation with iron. Analysis of the results allowed ascertain adverse changes in values of the erythrocytic system markers, occurring under the influence of the applied mixture of food additives. Used food additives change the iron metabolism, most likely from the necessity of applied xenobiotics biotransformation by heme-containing monoxygenases of P-450 cytochrome.

  2. Dietary iron intake and iron status of German female vegans: results of the German vegan study.

    Science.gov (United States)

    Waldmann, Annika; Koschizke, Jochen W; Leitzmann, Claus; Hahn, Andreas

    2004-01-01

    As shown in previous studies vegetarians and especially vegans are at risk for iron deficiency. Our study evaluated the iron status of German female vegans. In this cross-sectional study, the dietary intakes of 75 vegan women were assessed by two 9-day food frequency questionnaires. The iron status was analyzed on the basis of blood parameters. Mean daily iron intake was higher than recommended by the German Nutrition Society. Still 42% of the female vegans or = 50 years (old women, OW). In all, 40% (tri-index model (TIM) 20%) of the YW and 12% (TIM 12%) of the OW were considered iron-deficient based on either serum ferritin levels of vegan diet should have their iron status monitored and should consider taking iron supplements in case of a marginal status. Copyright 2004 S. Karger AG, Basel

  3. Iron Sulfur and Molybdenum Cofactor Enzymes Regulate the Drosophila Life Cycle by Controlling Cell Metabolism

    Science.gov (United States)

    Marelja, Zvonimir; Leimkühler, Silke; Missirlis, Fanis

    2018-01-01

    Iron sulfur (Fe-S) clusters and the molybdenum cofactor (Moco) are present at enzyme sites, where the active metal facilitates electron transfer. Such enzyme systems are soluble in the mitochondrial matrix, cytosol and nucleus, or embedded in the inner mitochondrial membrane, but virtually absent from the cell secretory pathway. They are of ancient evolutionary origin supporting respiration, DNA replication, transcription, translation, the biosynthesis of steroids, heme, catabolism of purines, hydroxylation of xenobiotics, and cellular sulfur metabolism. Here, Fe-S cluster and Moco biosynthesis in Drosophila melanogaster is reviewed and the multiple biochemical and physiological functions of known Fe-S and Moco enzymes are described. We show that RNA interference of Mocs3 disrupts Moco biosynthesis and the circadian clock. Fe-S-dependent mitochondrial respiration is discussed in the context of germ line and somatic development, stem cell differentiation and aging. The subcellular compartmentalization of the Fe-S and Moco assembly machinery components and their connections to iron sensing mechanisms and intermediary metabolism are emphasized. A biochemically active Fe-S core complex of heterologously expressed fly Nfs1, Isd11, IscU, and human frataxin is presented. Based on the recent demonstration that copper displaces the Fe-S cluster of yeast and human ferredoxin, an explanation for why high dietary copper leads to cytoplasmic iron deficiency in flies is proposed. Another proposal that exosomes contribute to the transport of xanthine dehydrogenase from peripheral tissues to the eye pigment cells is put forward, where the Vps16a subunit of the HOPS complex may have a specialized role in concentrating this enzyme within pigment granules. Finally, we formulate a hypothesis that (i) mitochondrial superoxide mobilizes iron from the Fe-S clusters in aconitase and succinate dehydrogenase; (ii) increased iron transiently displaces manganese on superoxide dismutase, which

  4. Iron Sulfur and Molybdenum Cofactor Enzymes Regulate the Drosophila Life Cycle by Controlling Cell Metabolism

    Directory of Open Access Journals (Sweden)

    Zvonimir Marelja

    2018-02-01

    Full Text Available Iron sulfur (Fe-S clusters and the molybdenum cofactor (Moco are present at enzyme sites, where the active metal facilitates electron transfer. Such enzyme systems are soluble in the mitochondrial matrix, cytosol and nucleus, or embedded in the inner mitochondrial membrane, but virtually absent from the cell secretory pathway. They are of ancient evolutionary origin supporting respiration, DNA replication, transcription, translation, the biosynthesis of steroids, heme, catabolism of purines, hydroxylation of xenobiotics, and cellular sulfur metabolism. Here, Fe-S cluster and Moco biosynthesis in Drosophila melanogaster is reviewed and the multiple biochemical and physiological functions of known Fe-S and Moco enzymes are described. We show that RNA interference of Mocs3 disrupts Moco biosynthesis and the circadian clock. Fe-S-dependent mitochondrial respiration is discussed in the context of germ line and somatic development, stem cell differentiation and aging. The subcellular compartmentalization of the Fe-S and Moco assembly machinery components and their connections to iron sensing mechanisms and intermediary metabolism are emphasized. A biochemically active Fe-S core complex of heterologously expressed fly Nfs1, Isd11, IscU, and human frataxin is presented. Based on the recent demonstration that copper displaces the Fe-S cluster of yeast and human ferredoxin, an explanation for why high dietary copper leads to cytoplasmic iron deficiency in flies is proposed. Another proposal that exosomes contribute to the transport of xanthine dehydrogenase from peripheral tissues to the eye pigment cells is put forward, where the Vps16a subunit of the HOPS complex may have a specialized role in concentrating this enzyme within pigment granules. Finally, we formulate a hypothesis that (i mitochondrial superoxide mobilizes iron from the Fe-S clusters in aconitase and succinate dehydrogenase; (ii increased iron transiently displaces manganese on superoxide

  5. Knockdown of proteins involved in iron metabolism limits tick reproduction and development

    Czech Academy of Sciences Publication Activity Database

    Hajdušek, O.; Sojka, Daniel; Kopáček, Petr; Burešová, Veronika; Franta, Zdeněk; Šauman, Ivo; Winzerling, J.; Grubhoffer, L.

    2009-01-01

    Roč. 106, č. 4 (2009), s. 1033-1038 ISSN 0027-8424 R&D Projects: GA MŠk(CZ) LC06009; GA MŠk LC07032; GA AV ČR IAA600220603 Institutional research plan: CEZ:AV0Z60220518; CEZ:AV0Z50070508 Keywords : tick ferritin * iron metabolism * RNA interference Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 9.432, year: 2009

  6. Defluoridation by Bacteriogenic Iron Oxides: Sorption Studies

    Science.gov (United States)

    Evans, K.; Ferris, F.

    2009-05-01

    At concentrations above 1 mg/L, fluoride in drinking water can lead to dental and skeletal fluorosis, a disease that causes mottling of the teeth, calcification of ligaments, crippling bone deformities and many other physiological disorders that can, ultimately, lead to death. Conservative estimates are that fluorosis afflicts tens of millions of people worldwide. As there is no treatment for fluorosis, prevention is the only means of controlling the disease. While numerous defluoridation techniques have been explored, no single method has been found to be both effective and inexpensive enough to implement widely. Our research began in India, with a large-scale geochemical study of the groundwater in a fluoride-contaminated region of Orissa. Having developed a better understanding of the geochemical relationships that exist between fluoride and other parameters present in an affected area, as well as the complex relationships that arise among those parameters that can impact the presence of fluoride, we began investigating certain remediation scenarios involving iron oxides. A common approach to remediation involves the partitioning of fluoride from groundwater by sorption onto a variety of materials, one of the most effective of which is iron oxide whose surface area acts as a scavenger for fluoride. In the presence of iron oxidizing bacteria, the oxidation rate of iron has been shown to be ˜6 times greater than in their absence; fluoride should, therefore, be removed from an aqueous environment by bacteriogenic iron oxides (BIOS) much more quickly than by abiotic iron oxides. Most recently, sorption studies have been conducted using both BIOS and synthetic hydrous ferric oxides in order to compare the behavior between biotic and abiotic sorbents. These studies have provided sorption isotherms that allow comparison of fluoride removed by sorption to BIOS versus synthetic iron oxides. Sorption affinity constants have also been determined, which allow for the

  7. New Insights on Iron Study in Myelodysplasia

    Directory of Open Access Journals (Sweden)

    Noha M. El Husseiny

    2014-12-01

    Full Text Available OBJECTIVE: Hepcidin plays a pivotal role in iron homeostasis. It is predominantly produced by hepatocytes and inhibits iron release from macrophages and iron uptake by intestinal epithelial cells. Competitive ELISA is the current method of choice for the quantification of serum hepcidin because of its lower detection limit, low costs, and high throughput. This study aims to discuss the role of hepcidin in the pathogenesis of iron overload in recently diagnosed myelodysplasia (MDS cases. METHODS: The study included 21 recently diagnosed MDS patients and 13 healthy controls. Ferritin, hepcidin, and soluble transferrin receptor (sTFR were measured in all subjects. RESULTS: There were 7 cases of hypocellular MDS, 8 cases of refractory cytopenia with multilineage dysplasia, and 6 cases of refractory anemia with excess blasts. No difference was observed among the 3 MDS subtypes in terms of hepcidin, sTFR, and ferritin levels (p>0.05. Mean hepcidin levels in the MDS and control groups were 55.8±21.5 ng/mL and 19.9±2.6 ng/ mL, respectively. Mean sTFR was 45.7±8.8 nmol/L in MDS patients and 31.1±5.6 nmol/L in the controls. Mean ferritin levels were significantly higher in MDS patients than in controls (539.14±83.5 ng/mL vs. 104.6±42.9 ng/mL, p0.05. CONCLUSION: Hepcidin may not be the main cause of iron overload in MDS. Further studies are required to test failure of production or peripheral unresponsiveness to hepcidin in MDS cases.

  8. Free Radical Oxidation Induced by Iron Metabolism Disorder in Femoral and Pelvic Fractures and Potential for Its Correction

    Directory of Open Access Journals (Sweden)

    Y. P. Orlov

    2016-01-01

    Full Text Available Objective: To determine the pathogenic significance of iron ions in the activation of free radical oxidation in trau matic disease and valuate the efficacy of Desferal in the complex therapy of patients with femoral and pelvic fractions.Materials and methods. Iron metabolism and the intensity of free radical oxidation have been studed in 30 patients with traumas. The patients were randomized into two groups by gender, age and the severity of injury. Group I (n=15 included the injured patients who received the standard intensive therapy. Group II (n=15 included the patients who were treated with Desferal of 8 mg/kg twice daily in 12 hours along with the intensive therapy. The control group comprized of 10 healthy individuals of the same age. The concentration of total and free hemoglobine, serum iron, transferrin, total antioxidant activity of blood serum, the intensity of free radical oxida tion by the Fe2+induced chemiluminescence and hemostatic parameters were studied on admittance as well as on 3rd and 5th day of hospitalization. The parameters of sistemic hemodyamics were checked by integral rheovasog raphy. Statistical processing of data was carried out using Biostat and MS Excel software. The results were pre sented as a mean and standart deviation (M±δ. The Student’s (t and MannWhitney tests were used to prove the hypotheses. The critical level of significance was P=0.05.Results. It was determined that the disorders of iron metabolism in patients with traumatic disease were accompanied by intra and extravascular hemolysis, the excess off reduced iron ions catalizing the free radical oxidation, and failure of antioxidant system and disorders of hemostatic system and central hemodynamics. Desferal lowered the level of reduced iron in blood serum, diminished the intensity of free radical oxidation and eliminated the disorders in hemostasis and systemic hemodynamics.Conclusion. Data confirm the pathogenic role of iron ions in the

  9. Oral sucrosomial iron versus intravenous iron in anemic cancer patients without iron deficiency receiving darbepoetin alfa: a pilot study.

    Science.gov (United States)

    Mafodda, Antonino; Giuffrida, D; Prestifilippo, A; Azzarello, D; Giannicola, R; Mare, M; Maisano, R

    2017-09-01

    Erythropoiesis-stimulating agents (ESAs) are often used in treatment of patients with chemotherapy-induced anemia. Many studies have demonstrated an improved hemoglobin (Hb) response when ESA is combined with intravenous iron supplementation and a higher effectiveness of intravenous iron over traditional oral iron formulations. A new formulation of oral sucrosomial iron featuring an increased bioavailability compared to traditional oral formulations has recently become available and could provide a valid alternative to those by intravenous (IV) route. Our study evaluated the performance of sucrosomial iron versus intravenous iron in increasing hemoglobin in anemic cancer patients receiving chemotherapy and darbepoetin alfa, as well as safety, need of transfusion, and quality of life (QoL). The present study considered a cohort of 64 patients with chemotherapy-related anemia (Hb >8 g/dL iron deficiency, scheduled to receive chemotherapy and darbepoetin. All patients received darbepoetin alfa 500 mcg once every 3 weeks and were randomly assigned to receive 8 weeks of IV ferric gluconate 125 mg weekly or oral sucrosomial iron 30 mg daily. The primary endpoint was to demonstrate the performance of oral sucrosomial iron in improving Hb response, compared to intravenous iron. The Hb response was defined as the Hb increase ≥2 g/dL from baseline or the attainment Hb ≥ 12 g/dL. There was no difference in the Hb response rate between the two treatment arms. Seventy one percent of patients treated with IV iron achieved an erythropoietic response, compared to 70% of patients treated with oral iron. By conventional criteria, this difference is considered to be not statistically significant. There were also no differences in the proportion of patients requiring red blood cell transfusions and changes in QoL. Sucrosomial oral iron was better tolerated. In cancer patients with chemotherapy-related anemia receiving darbepoetin alfa, sucrosomial oral iron provides

  10. An insight into the metabolic responses of ultra-small superparamagnetic particles of iron oxide using metabonomic analysis of biofluids

    Science.gov (United States)

    Feng, Jianghua; Liu, Huili; Zhang, Limin; Bhakoo, Kishore; Lu, Lehui

    2010-10-01

    Ultra-small superparamagnetic particles of iron oxides (USPIO) have been developed as intravenous organ/tissue-targeted contrast agents to improve magnetic resonance imaging (MRI) in vivo. However, their potential toxicity and effects on metabolism have attracted particular attention. In the present study, uncoated and dextran-coated USPIO were investigated by analyzing both rat urine and plasma metabonomes using high-resolution NMR-based metabonomic analysis in combination with multivariate statistical analysis. The wealth of information gathered on the metabolic profiles from rat urine and plasma has revealed subtle metabolic changes in response to USPIO administration. The metabolic changes include the elevation of urinary α-hydroxy-n-valerate, o- and p-HPA, PAG, nicotinate and hippurate accompanied by decreases in the levels of urinary α-ketoglutarate, succinate, citrate, N-methylnicotinamide, NAG, DMA, allantoin and acetate following USPIO administration. The changes associated with USPIO administration included a gradual increase in plasma glucose, N-acetyl glycoprotein, saturated fatty acid, citrate, succinate, acetate, GPC, ketone bodies (β-hydroxybutyrate, acetone and acetoacetate) and individual amino acids, such as phenylalanine, lysine, isoleucine, glycine, glutamine and glutamate and a gradual decrease of myo-inositol, unsaturated fatty acid and triacylglycerol. Hence USPIO administration effects are reflected in changes in a number of metabolic pathways including energy, lipid, glucose and amino acid metabolism. The size- and surface chemistry-dependent metabolic responses and possible toxicity were observed using NMR analysis of biofluids. These changes may be attributed to the disturbances of hepatic, renal and cardiac functions following USPIO administrations. The potential biotoxicity can be derived from metabonomic analysis and serum biochemistry analysis. Metabonomic strategy offers a promising approach for the detection of subtle

  11. An insight into the metabolic responses of ultra-small superparamagnetic particles of iron oxide using metabonomic analysis of biofluids

    Energy Technology Data Exchange (ETDEWEB)

    Feng Jianghua [Department of Physics, Fujian Key Laboratory of Plasma and Magnetic Resonance, State Key Laboratory of Physical Chemistry of Solid Surfaces, Xiamen University, Xiamen, 361005 (China); Liu Huili; Zhang Limin [State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071 (China); Bhakoo, Kishore [Singapore Bioimaging Consortium, Agency for Science, Technology and Research (A-STAR) 138667 (Singapore); Lu Lehui, E-mail: jianghua.feng@hotmail.com, E-mail: jianghua.feng@wipm.ac.cn [State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022 (China)

    2010-10-01

    Ultra-small superparamagnetic particles of iron oxides (USPIO) have been developed as intravenous organ/tissue-targeted contrast agents to improve magnetic resonance imaging (MRI) in vivo. However, their potential toxicity and effects on metabolism have attracted particular attention. In the present study, uncoated and dextran-coated USPIO were investigated by analyzing both rat urine and plasma metabonomes using high-resolution NMR-based metabonomic analysis in combination with multivariate statistical analysis. The wealth of information gathered on the metabolic profiles from rat urine and plasma has revealed subtle metabolic changes in response to USPIO administration. The metabolic changes include the elevation of urinary {alpha}-hydroxy-n-valerate, o- and p-HPA, PAG, nicotinate and hippurate accompanied by decreases in the levels of urinary {alpha}-ketoglutarate, succinate, citrate, N-methylnicotinamide, NAG, DMA, allantoin and acetate following USPIO administration. The changes associated with USPIO administration included a gradual increase in plasma glucose, N-acetyl glycoprotein, saturated fatty acid, citrate, succinate, acetate, GPC, ketone bodies ({beta}-hydroxybutyrate, acetone and acetoacetate) and individual amino acids, such as phenylalanine, lysine, isoleucine, glycine, glutamine and glutamate and a gradual decrease of myo-inositol, unsaturated fatty acid and triacylglycerol. Hence USPIO administration effects are reflected in changes in a number of metabolic pathways including energy, lipid, glucose and amino acid metabolism. The size- and surface chemistry-dependent metabolic responses and possible toxicity were observed using NMR analysis of biofluids. These changes may be attributed to the disturbances of hepatic, renal and cardiac functions following USPIO administrations. The potential biotoxicity can be derived from metabonomic analysis and serum biochemistry analysis. Metabonomic strategy offers a promising approach for the detection of

  12. An insight into the metabolic responses of ultra-small superparamagnetic particles of iron oxide using metabonomic analysis of biofluids

    International Nuclear Information System (INIS)

    Feng Jianghua; Liu Huili; Zhang Limin; Bhakoo, Kishore; Lu Lehui

    2010-01-01

    Ultra-small superparamagnetic particles of iron oxides (USPIO) have been developed as intravenous organ/tissue-targeted contrast agents to improve magnetic resonance imaging (MRI) in vivo. However, their potential toxicity and effects on metabolism have attracted particular attention. In the present study, uncoated and dextran-coated USPIO were investigated by analyzing both rat urine and plasma metabonomes using high-resolution NMR-based metabonomic analysis in combination with multivariate statistical analysis. The wealth of information gathered on the metabolic profiles from rat urine and plasma has revealed subtle metabolic changes in response to USPIO administration. The metabolic changes include the elevation of urinary α-hydroxy-n-valerate, o- and p-HPA, PAG, nicotinate and hippurate accompanied by decreases in the levels of urinary α-ketoglutarate, succinate, citrate, N-methylnicotinamide, NAG, DMA, allantoin and acetate following USPIO administration. The changes associated with USPIO administration included a gradual increase in plasma glucose, N-acetyl glycoprotein, saturated fatty acid, citrate, succinate, acetate, GPC, ketone bodies (β-hydroxybutyrate, acetone and acetoacetate) and individual amino acids, such as phenylalanine, lysine, isoleucine, glycine, glutamine and glutamate and a gradual decrease of myo-inositol, unsaturated fatty acid and triacylglycerol. Hence USPIO administration effects are reflected in changes in a number of metabolic pathways including energy, lipid, glucose and amino acid metabolism. The size- and surface chemistry-dependent metabolic responses and possible toxicity were observed using NMR analysis of biofluids. These changes may be attributed to the disturbances of hepatic, renal and cardiac functions following USPIO administrations. The potential biotoxicity can be derived from metabonomic analysis and serum biochemistry analysis. Metabonomic strategy offers a promising approach for the detection of subtle

  13. Acetylcholinesterase-independent protective effects of huperzine A against iron overload-induced oxidative damage and aberrant iron metabolism signaling in rat cortical neurons.

    Science.gov (United States)

    Tao, Ling-Xue; Huang, Xiao-Tian; Chen, Yu-Ting; Tang, Xi-Can; Zhang, Hai-Yan

    2016-11-01

    Iron dyshomeostasis is one of the primary causes of neuronal death in Alzheimer's disease (AD). Huperzine A (HupA), a natural inhibitor of acetylcholinesterase (AChE), is a licensed anti-AD drug in China and a nutraceutical in the United Sates. Here, we investigated the protective effects of HupA against iron overload-induced injury in neurons. Rat cortical neurons were treated with ferric ammonium citrate (FAC), and cell viability was assessed with MTT assays. Reactive oxygen species (ROS) assays and adenosine triphosphate (ATP) assays were performed to assess mitochondrial function. The labile iron pool (LIP) level, cytosolic-aconitase (c-aconitase) activity and iron uptake protein expression were measured to determine iron metabolism changes. The modified Ellman's method was used to evaluate AChE activity. HupA significantly attenuated the iron overload-induced decrease in neuronal cell viability. This neuroprotective effect of HupA occurred concurrently with a decrease in ROS and an increase in ATP. Moreover, HupA treatment significantly blocked the upregulation of the LIP level and other aberrant iron metabolism changes induced by iron overload. Additionally, another specific AChE inhibitor, donepezil (Don), at a concentration that caused AChE inhibition equivalent to that of HupA negatively, influenced the aberrant changes in ROS, ATP or LIP that were induced by excessive iron. We provide the first demonstration of the protective effects of HupA against iron overload-induced neuronal damage. This beneficial role of HupA may be attributed to its attenuation of oxidative stress and mitochondrial dysfunction and elevation of LIP, and these effects are not associated with its AChE-inhibiting effect.

  14. Studying and improving blast furnace cast iron quality

    Directory of Open Access Journals (Sweden)

    Т. К. Balgabekov

    2014-10-01

    Full Text Available In the article there are presented the results of studies to improve the quality of blast furnace cast iron. It was established that using fire clay suspension for increasing the mould covering heat conductivity improves significantly pig iron salable condition and filtration refining method decreases iron contamination by nonmetallic inclusions by 50 – 70 %.

  15. Trend overtime of total haemoglobin, iron metabolism and trace minerals in veal calves fed high amounts of two different solid feeds

    Directory of Open Access Journals (Sweden)

    Anna-Lisa Stefani

    2010-01-01

    Full Text Available Fifty Polish Friesian veal calves were administrated high amounts of two different solid feeds (maize grain and a mix diet containing 10% of straw and 8% of soy in addition to the traditional milk replacer diet. Compared to the mix diet, maize grain had a lower content of iron, copper and zinc and a minor fibre level. Effects of the two diets on calves’ blood haemoglobin, iron, iron metabolism parameters, copper and zinc concentrations were studied. Haemoglobin concentration resulted higher at the end of the fattening for calves fed the mix diet, as expected. Values remained, however, within ranges that allowed acceptable carcass paleness. Haematic iron, unsaturated iron binding capacity (UIBC and total iron binding capacity (TIBC levels were not significantly different between the two solid feeds. Lower copper and zinc blood concentrations resulted for calves fed the mix diet were likely due to the feed fibre interfering with the bioavailability of the two minerals, according to what happens for iron.

  16. Mechanistic Study of Monodisperse Iron Oxide Nanocrystals ...

    African Journals Online (AJOL)

    To gain better insight into the formation of iron oxide nanocrystals from the solution phase thermal decomposition of iron (III) oleate complex, different reaction conditions including time, heating ramp, as well as concentrations of iron oleate precursor and oleic acid ligand were systematically varied and the resulting ...

  17. Nutritional Immunity Triggers the Modulation of Iron Metabolism Genes in the Sub-Antarctic Notothenioid Eleginops maclovinus in Response to Piscirickettsia salmonis

    Directory of Open Access Journals (Sweden)

    Danixa Martínez

    2017-09-01

    Full Text Available Iron deprivation is a nutritional immunity mechanism through which fish can limit the amount of iron available to invading bacteria. The aim of this study was to evaluate the modulation of iron metabolism genes in the liver and brain of sub-Antarctic notothenioid Eleginops maclovinus challenged with Piscirickettsia salmonis. The specimens were inoculated with two P. salmonis strains: LF-89 (ATCC® VR-1361™ and Austral-005 (antibiotic resistant. Hepatic and brain samples were collected at intervals over a period of 35 days. Gene expression (by RT-qPCR of proteins involved in iron storage, transport, and binding were statistically modulated in infected fish when compared with control counterparts. Specifically, the expression profiles of the transferrin and hemopexin genes in the liver, as well as the expression profiles of ferritin-M, ferritin-L, and transferrin in the brain, were similar for both experimental groups. Nevertheless, the remaining genes such as ferritin-H, ceruloplasmin, hepcidin, and haptoglobin presented tissue-specific expression profiles that varied in relation to the injected bacterial strain and sampling time-point. These results suggest that nutritional immunity could be an important immune defense mechanism for E. maclovinus against P. salmonis injection. This study provides relevant information for understanding iron metabolism of a sub-Antarctic notothenioid fish.

  18. Iron metabolism in BeWo chorion carcinoma cells. Transferrin-mediated uptake and release of iron

    NARCIS (Netherlands)

    van der Ende, A.; du Maine, A.; Simmons, C. F.; Schwartz, A. L.; Strous, G. J.

    1987-01-01

    Growing human choriocarcinoma BeWo b24 cells contain 1.5 X 10(6) functional cell surface transferrin binding sites and 2.0 X 10(6) intracellular binding sites. These cells rapidly accumulate iron at a rate of 360,000 iron atoms/min/cell. During iron uptake the transferrin and its receptor recycle at

  19. The effect of alcoholic beverages on iron and zinc metabolism in the rat.

    Science.gov (United States)

    Fairweather-Tait, S J; Southon, S; Piper, Z

    1988-09-01

    1. Male Wistar rats (approximately 200 g) were given distilled water and a semi-synthetic control diet for 6 d. On day 7, 37 kBq 65Zn were administered intramuscularly and the rats were given distilled water, beer, cider, red wine, whisky or ethanol as their only source of fluid. The wine, whisky and ethanol were diluted so that each of the beverages contained a similar ethanol concentration (approximately 30 g/l). Food and fluid intake, growth rate and whole-body 65Zn were measured regularly over 11 d, after which animals were killed and blood haemoglobin (Hb) concentration, liver iron stores and the Zn concentration in testes determined. 2. There were no differences in body-weight gain or food intake between groups but fluid intake for the beer group was considerably higher than that for the other groups. 3. There was a significant effect of the type of alcoholic beverage consumed on whole-body 65Zn retention. Rats given whisky had a smaller daily loss of 65Zn than those given water, beer or cider. The ethanol group also showed a lower rate of 65Zn loss compared with the water group. The observed changes in whole-body 65Zn retention could be explained by an adverse influence of ethanol on Zn absorption from the diet. 4. Blood Hb and testes Zn concentration were similar in all groups but the type of liquid consumed influenced liver Fe levels. The cider group had the lowest liver Fe values and the ethanol group the highest values. 5. It is apparent from the present study that ethanol and alcoholic beverages affect Zn and Fe metabolism, but that the effects of ethanol are moderated by other components of the alcoholic beverages.

  20. Fungal Morphology, Iron Homeostasis, and Lipid Metabolism Regulated by a GATA Transcription Factor in Blastomyces dermatitidis.

    Directory of Open Access Journals (Sweden)

    Amber J Marty

    2015-06-01

    Full Text Available In response to temperature, Blastomyces dermatitidis converts between yeast and mold forms. Knowledge of the mechanism(s underlying this response to temperature remains limited. In B. dermatitidis, we identified a GATA transcription factor, SREB, important for the transition to mold. Null mutants (SREBΔ fail to fully complete the conversion to mold and cannot properly regulate siderophore biosynthesis. To capture the transcriptional response regulated by SREB early in the phase transition (0-48 hours, gene expression microarrays were used to compare SREB∆ to an isogenic wild type isolate. Analysis of the time course microarray data demonstrated SREB functioned as a transcriptional regulator at 37°C and 22°C. Bioinformatic and biochemical analyses indicated SREB was involved in diverse biological processes including iron homeostasis, biosynthesis of triacylglycerol and ergosterol, and lipid droplet formation. Integration of microarray data, bioinformatics, and chromatin immunoprecipitation identified a subset of genes directly bound and regulated by SREB in vivo in yeast (37°C and during the phase transition to mold (22°C. This included genes involved with siderophore biosynthesis and uptake, iron homeostasis, and genes unrelated to iron assimilation. Functional analysis suggested that lipid droplets were actively metabolized during the phase transition and lipid metabolism may contribute to filamentous growth at 22°C. Chromatin immunoprecipitation, RNA interference, and overexpression analyses suggested that SREB was in a negative regulatory circuit with the bZIP transcription factor encoded by HAPX. Both SREB and HAPX affected morphogenesis at 22°C; however, large changes in transcript abundance by gene deletion for SREB or strong overexpression for HAPX were required to alter the phase transition.

  1. Altered sterol metabolism in budding yeast affects mitochondrial iron-sulfur (Fe-S) cluster synthesis.

    Science.gov (United States)

    Ward, Diane M; Chen, Opal S; Li, Liangtao; Kaplan, Jerry; Bhuiyan, Shah Alam; Natarajan, Selvamuthu K; Bard, Martin; Cox, James E

    2018-05-17

    Ergosterol synthesis is essential for cellular growth and viability of the budding yeast Saccharomyces cerevisiae, and intracellular sterol distribution and homeostasis are therefore highly regulated in this species. Erg25 is an iron-containing C4-methyl sterol oxidase that contributes to the conversion of 4,4-dimethylzymosterol to zymosterol, a precursor of ergosterol. The ERG29 gene encodes an endoplasmic reticulum (ER)-associated protein, and here we identified a role for Erg29 in the methyl sterol oxidase step of ergosterol synthesis. ERG29 deletion resulted in lethality in respiring cells, but respiration-incompetent (Rho- or Rho0) cells survived, suggesting that Erg29 loss leads to accumulation of oxidized sterol metabolites that affect cell viability. Down-regulation of ERG29 expression in Δerg29 cells indeed led to accumulation of methyl sterol metabolites, resulting in increased mitochondrial oxidants and a decreased ability of mitochondria to synthesize iron-sulfur (Fe-S) clusters due to reduced levels of Yfh1, the mammalian frataxin homolog, which is involved in mitochondrial Fe metabolism. Using a high-copy genomic library, we identified suppressor genes that permitted growth of Δerg29 cells on respiratory substrates, and these included genes encoding the mitochondrial proteins Yfh1, Mmt1, Mmt2, and Pet20, which reversed all phenotypes associated with loss of ERG29. Of note, loss of Erg25 also resulted in accumulation of methyl sterol metabolites and also increased mitochondrial oxidants and degradation of Yfh1. We propose that accumulation of toxic intermediates of the methyl sterol oxidase reaction increase mitochondrial oxidants, which affect Yfh1 protein stability. These results indicate an interaction between sterols generated by ER proteins and mitochondrial iron metabolism. Published under license by The American Society for Biochemistry and Molecular Biology, Inc.

  2. Abnormal iron metabolism and oxidative stress in mice expressing a mutant form of the ferritin light polypeptide gene

    Science.gov (United States)

    Barbeito, Ana G.; Garringer, Holly J.; Baraibar, Martin A.; Gao, Xiaoying; Arredondo, Miguel; Núñez, Marco T.; Smith, Mark A.; Ghetti, Bernardino; Vidal, Ruben

    2009-01-01

    Insertional mutations in exon 4 of the ferritin light chain (FTL) gene are associated with hereditary ferritinopathy (HF) or neuroferritinopathy, an autosomal dominant neurodegenerative disease characterized by progressive impairment of motor and cognitive functions. To determine the pathogenic mechanisms by which mutations in FTL lead to neurodegeneration, we investigated iron metabolism and markers of oxidative stress in the brain of transgenic (Tg) mice that express the mutant human FTL498-499InsTC cDNA. Compared with wild-type mice, brain extracts from Tg (FTL-Tg) mice showed an increase in the cytoplasmic levels of both FTL and ferritin heavy chain polypeptides, a decrease in the protein and mRNA levels of transferrin receptor-1, and a significant increase in iron levels. Transgenic mice also showed the presence of markers for lipid peroxidation, protein carbonyls, and nitrone–protein adducts in the brain. However, gene expression analysis of iron management proteins in the liver of Tg mice indicates that the FTL-Tg mouse liver is iron deficient. Our data suggest that disruption of iron metabolism in the brain has a primary role in the process of neurodegeneration in HF and that the pathogenesis of HF is likely to result from a combination of reduction in iron storage function and enhanced toxicity associated with iron-induced ferritin aggregates in the brain. PMID:19519778

  3. Iron

    DEFF Research Database (Denmark)

    Hansen, Jakob Bondo; Moen, I W; Mandrup-Poulsen, T

    2014-01-01

    and discuss recent evidence, suggesting that iron is a key pathogenic factor in both type 1 and type 2 diabetes with a focus on inflammatory pathways. Pro-inflammatory cytokine-induced β-cell death is not fully understood, but may include iron-induced ROS formation resulting in dedifferentiation by activation...... of transcription factors, activation of the mitochondrial apoptotic machinery or of other cell death mechanisms. The pro-inflammatory cytokine IL-1β facilitates divalent metal transporter 1 (DMT1)-induced β-cell iron uptake and consequently ROS formation and apoptosis, and we propose that this mechanism provides...

  4. Iron

    Science.gov (United States)

    ... Share: Search the ODS website Submit Search NIH Office of Dietary Supplements Consumer Datos en español Health ... eating a variety of foods, including the following: Lean meat, seafood, and poultry. Iron-fortified breakfast cereals ...

  5. Modulation of iron metabolism in aging and in Alzheimer’s disease: relevance of the choroid plexus.

    Directory of Open Access Journals (Sweden)

    Sandro Da Mesquita

    2012-05-01

    Full Text Available Iron is essential for mammalian cellular homeostasis. However, in excess, it promotes free radical formation and is associated with aging-related progressive deterioration and with neurodegenerative disorders such as Alzheimer’s disease (AD. There are no mechanisms to excrete iron, which makes iron homeostasis a very tightly regulated process at the level of the intestinal absorption. Iron is believed to reach the brain through receptor mediated endocytosis of iron-bound transferrin by the brain barriers, the blood-cerebrospinal (CSF fluid barrier, formed by the choroid plexus (CP epithelial cells and the blood-brain barrier formed by the endothelial cells of the brain capillaries. Importantly, the CP epithelial cells are responsible for producing most of the CSF, the fluid that fills the brain ventricles and the subarachnoid space. Recently, the finding that the CP epithelial cells display all the machinery to locally control iron delivery into the CSF may suggest that the general and progressive senescence of the CP may be at the basis of the impairment of regional iron metabolism, iron-mediated toxicity and the increase in inflammation and oxidative stress that occurs with aging and, particularly, in AD.

  6. Moessbauer study of hydrated iron sulfates

    International Nuclear Information System (INIS)

    Araujo, S.I.; Danon, J.; Iannarella, L.

    1991-01-01

    The hydrated iron sulfates amarantite Fe(SO sub(4))(OH).3H sub(2)O, copiapite (Mg,Al)Fe sup(3+) sub(4)(SO sub(4)) sub(6)(OH) sub(2).20H sub(2)O and ungemachite K sub(3)Na sub(9)Fe(SO sub(4)) sub(6)(OH) sub(3).9H sub(2)O were studied by Moessbauer Spectroscopy (MS) in connection with Differential Scanning Calorimetry (DSC). The effect of the dehydration on the hyperfine parameters at the Fe sites was investigated. For amarantite, the Moessbauer spectrum remained practically unchanged, while the Fe sup(3+) quadrupole splittings for copiapite and ungemachite increased. The Fe sup(2+) quadrupole splitting of ungemachite was also unchanged. We have found out the anisotropy of the recoiless absorption probability for the sup(57)Fe Moessbauer gamma ray in amarantite. The three minerals were found to be highly hygroscopic after the dehydration consequent of the DSC measurements. (author)

  7. [The effect of exogenous antioxidants on the antioxidant status of erythrocytes and hepcidin content in blood of patients with disorders of iron metabolism regulation].

    Science.gov (United States)

    Shcherbinina, S P; Levina, A A; Lisovskaia, I L; Ataullakhanov, F I

    2013-01-01

    In many diseases associated with impairments in iron metabolism, erythrocytes exhibit an increased sensitivity to oxidative stress induced in vitro. In this study, we have examined the antioxidant status of erythrocytes from healthy donors and from 12 patients with disorders of iron homeostasis by measuring the extent of t-BHP-induced hemolysis in vitro. The extent of hemolysis observed with patient erythrocytes was significantly higher than that observed in experiment with normal cells. After therapeutic infusions of the antioxidants mexidol or emoxypin, oxidative hemolysis in patients was restored to normal values and blood hepcidin content increased significantly. A significant correlation was observed between hepcidin concentration after treatment and t-BHP-induced hemolysis before treatment. These data suggest that antioxidants may exert a favorable effect under pathological conditions associated with iron overload disease.

  8. Transcriptome Analysis of the Intracellular Facultative Pathogen Piscirickettsia salmonis: Expression of Putative Groups of Genes Associated with Virulence and Iron Metabolism.

    Directory of Open Access Journals (Sweden)

    Alvaro Machuca

    Full Text Available The intracellular facultative bacteria Piscirickettsia salmonis is one of the most important pathogens of the Chilean aquaculture. However, there is a lack of information regarding the whole genomic transcriptional response according to different extracellular environments. We used next generation sequencing (NGS of RNA (RNA-seq to study the whole transcriptome of an isolate of P. salmonis (FAVET-INBIOGEN using a cell line culture and a modified cell-free liquid medium, with or without iron supplementation. This was done in order to obtain information about the factors there are involved in virulence and iron acquisition. First, the isolate was grown in the Sf21 cell line; then, the bacteria were cultured into a cell-free liquid medium supplemented or not with iron. We identified in the transcriptome, genes associated with type IV secretion systems, genes related to flagellar structure assembly, several proteases and sigma factors, and genes related to the development of drug resistance. Additionally, we identified for the first time several iron-metabolism associated genes including at least two iron uptake pathways (ferrous iron and ferric iron uptake that are actually expressed in the different conditions analyzed. We further describe putative genes that are related with the use and storage of iron in the bacteria, which have not been previously described. Several sets of genes related to virulence were expressed in both the cell line and cell-free culture media (for example those related to flagellar structure; such as basal body, MS-ring, C-ring, proximal and distal rod, and filament, which may play roles in other basic processes rather than been restricted to virulence.

  9. Nuclear resonance vibrational spectroscopic studies of iron-containing biomolecules

    International Nuclear Information System (INIS)

    Ohta, Takehiro; Seto, Makoto

    2014-01-01

    In this review, we report recent nuclear resonance vibrational spectroscopic (NRVS) studies of iron-containing biomolecules and their model complexes. The NRVS is synchrotron-based element-specific vibrational spectroscopic methods. Unlike Raman and infrared spectroscopy, the NRVS can investigate all iron motions without selection rules, which provide atomic level insights into the structure/reactivity correlation of biologically relevant iron complexes. (author)

  10. The A736V TMPRSS6 polymorphism influences hepcidin and iron metabolism in chronic hemodialysis patients: TMPRSS6 and hepcidin in hemodialysis

    Directory of Open Access Journals (Sweden)

    Pelusi Serena

    2013-02-01

    Full Text Available Abstract Background Aim of this study was to evaluate whether the A736V TMPRSS6 polymorphism, a major genetic determinant of iron metabolism in healthy subjects, influences serum levels of hepcidin, the hormone regulating iron metabolism, and erythropoiesis in chronic hemodialysis (CHD. Methods To this end, we considered 199 CHD patients from Northern Italy (157 with hepcidin evaluation, and 188 healthy controls without iron deficiency, matched for age and gender. Genetic polymorphisms were evaluated by allele specific polymerase chain reaction assays, and hepcidin quantified by mass spectrometry. Results Serum hepcidin levels were not different between the whole CHD population and controls (median 7.1, interquartile range (IQR 0.55-17.1 vs. 7.4, 4.5-17.9 nM, respectively, but were higher in the CHD subgroup after exclusion of subjects with relative iron deficiency (p = 0.04. In CHD patients, the A736V TMPRSS6 polymorphism influenced serum hepcidin levels in individuals positive for mutations in the HFE gene of hereditary hemochromatosis (p 30 ng/ml; n = 86, hepcidin was associated with lower mean corpuscular volume (p = 0.002, suggesting that it contributed to iron-restricted erythropoiesis. In line with previous results, in patients without acute inflammation and severe iron deficiency the “high hepcidin” 736 V TMPRSS6 variant was associated with higher erythropoietin maintenance dose (p = 0.016, independently of subclinical inflammation (p = 0.02. Conclusions The A736V TMPRSS6 genotype influences hepcidin levels, erythropoiesis, and anemia management in CHD patients. Evaluation of the effect of TMPRSS6 genotype on clinical outcomes in prospective studies in CHD may be useful to predict the outcomes of hepcidin manipulation, and to guide treatment personalization by optimizing anemia management.

  11. Study of Ascorbic Acid as Iron(III Reducing Agent for Spectrophotometric Iron Speciation

    Directory of Open Access Journals (Sweden)

    Antesar Elmagirbi

    2012-10-01

    Full Text Available The study of ascorbic acid as a reducing agent for iron(III has been investigated in order to obtain an alternative carcinogenic reducing agent, hydroxylamine, used in spectrophotometric standard method based on the formation of a red-orange complex of Fe(II-o-phenanthroline. The study was optimised with regards to ascorbic acid concentration as well as pH solution. The results showed that ascorbic acid showed maximum capacity as reducing agent of iron(III under concentration of 4.46.10-4 M and pH solution of 1-4.Under these conditions, ascorbic acid reduced iron(III proportionally and performed similarly to that of hydroxylamine.  The method gave result to linear calibration over the range of 0.2-2 mg/L withhigh accuracy of 97 % and relative standard deviation of less than 2 %. This method was successfully applied to assay iron speciation in water samples.

  12. Theoretical Study of Spin Crossover in 30 Iron Complexes.

    Science.gov (United States)

    Kepp, Kasper P

    2016-03-21

    Iron complexes are important spin crossover (SCO) systems with vital roles in oxidative metabolism and promising technological potential. The SCO tendency depends on the free energy balance of high- and low-spin states, which again depends on physical effects such as dispersion, relativistic effects, and vibrational entropy. This work studied 30 different iron SCO systems with experimentally known thermochemical data, using 12 different density functionals. Remarkably general entropy-enthalpy compensation across SCO systems was identified (R = 0.82, p = 0.002) that should be considered in rational SCO design. Iron(II) complexes displayed higher ΔH and ΔS values than iron(III) complexes and also less steep compensation effects. First-coordination sphere ΔS values computed from numerical frequencies reproduce most of the experimental entropy and should thus be included when modeling spin-state changes in inorganic chemistry (R = 0.52, p = 3.4 × 10(-3); standard error in TΔS ≈ 4.4 kJ/mol at 298 K vs 16 kJ/mol of total TΔS on average). Zero-point energies favored high-spin states by 9 kJ/mol on average. Interestingly, dispersion effects are surprisingly large for the SCO process (average: 9 kJ/mol, but up to 33 kJ/mol) and favor the more compact low-spin state. Relativistic effects favor low-spin by ∼9 kJ/mol on average, but up to 24 kJ/mol. B3LYP*, TPSSh, B2PLYP, and PW6B95 performed best for the typical calculation scheme that includes ZPE. However, if relativistic and dispersion effects are included, only B3LYP* remained accurate. On average, high-spin was favored by LYP by 11-15 kJ/mol relative to other correlation functionals, and by 4.2 kJ/mol per 1% HF exchange in hybrids. 13% HF exchange was optimal without dispersion, and 15% was optimal with all effects included for these systems.

  13. Knocking down mitochondrial iron transporter (MIT) reprograms primary and secondary metabolism in rice plants.

    Science.gov (United States)

    Vigani, Gianpiero; Bashir, Khurram; Ishimaru, Yasuhiro; Lehmann, Martin; Casiraghi, Fabio Marco; Nakanishi, Hiromi; Seki, Motoaki; Geigenberger, Peter; Zocchi, Graziano; Nishizawa, Naoko K

    2016-03-01

    Iron (Fe) is an essential micronutrient for plant growth and development, and its reduced bioavailability strongly impairs mitochondrial functionality. In this work, the metabolic adjustment in the rice (Oryza sativa) mitochondrial Fe transporter knockdown mutant (mit-2) was analysed. Biochemical characterization of purified mitochondria from rice roots showed alteration in the respiratory chain of mit-2 compared with wild-type (WT) plants. In particular, proteins belonging to the type II alternative NAD(P)H dehydrogenases accumulated strongly in mit-2 plants, indicating that alternative pathways were activated to keep the respiratory chain working. Additionally, large-scale changes in the transcriptome and metabolome were observed in mit-2 rice plants. In particular, a strong alteration (up-/down-regulation) in the expression of genes encoding enzymes of both primary and secondary metabolism was found in mutant plants. This was reflected by changes in the metabolic profiles in both roots and shoots of mit-2 plants. Significant alterations in the levels of amino acids belonging to the aspartic acid-related pathways (aspartic acid, lysine, and threonine in roots, and aspartic acid and ornithine in shoots) were found that are strictly connected to the Krebs cycle. Furthermore, some metabolites (e.g. pyruvic acid, fumaric acid, ornithine, and oligosaccharides of the raffinose family) accumulated only in the shoot of mit-2 plants, indicating possible hypoxic responses. These findings suggest that the induction of local Fe deficiency in the mitochondrial compartment of mit-2 plants differentially affects the transcript as well as the metabolic profiles in root and shoot tissues. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  14. Microbial communities from different subsystems in biological heap leaching system play different roles in iron and sulfur metabolisms.

    Science.gov (United States)

    Xiao, Yunhua; Liu, Xueduan; Ma, Liyuan; Liang, Yili; Niu, Jiaojiao; Gu, Yabing; Zhang, Xian; Hao, Xiaodong; Dong, Weiling; She, Siyuan; Yin, Huaqun

    2016-08-01

    The microbial communities are important for minerals decomposition in biological heap leaching system. However, the differentiation and relationship of composition and function of microbial communities between leaching heap (LH) and leaching solution (LS) are still unclear. In this study, 16S rRNA gene sequencing was used to assess the microbial communities from the two subsystems in ZiJinShan copper mine (Fujian province, China). Results of PCoA and dissimilarity test showed that microbial communities in LH samples were significantly different from those in LS samples. The dominant genera of LH was Acidithiobacillus (57.2 ∼ 87.9 %), while Leptospirillum (48.6 ∼ 73.7 %) was predominant in LS. Environmental parameters (especially pH) were the major factors to influence the composition and structure of microbial community by analysis of Mantel tests. Results of functional test showed that microbial communities in LH utilized sodium thiosulfate more quickly and utilized ferrous sulfate more slowly than those in LS, which further indicated that the most sulfur-oxidizing processes of bioleaching took place in LH and the most iron-oxidizing processes were in LS. Further study found that microbial communities in LH had stronger pyrite leaching ability, and iron extraction efficiency was significantly positively correlated with Acidithiobacillus (dominated in LH), which suggested that higher abundance ratio of sulfur-oxidizing microbes might in favor of minerals decomposition. Finally, a conceptual model was designed through the above results to better exhibit the sulfur and iron metabolism in bioleaching systems.

  15. Practice guidelines for the diagnosis and management of microcytic anemias due to genetic disorders of iron metabolism or heme synthesis

    NARCIS (Netherlands)

    Donker, A.E.; Raymakers, R.A.P.; Vlasveld, L.T.; Barneveld, T. van; Terink, R.; Dors, N.; Brons, P.P.T.; Knoers, N.V.A.M.; Swinkels, D.W.

    2014-01-01

    During recent years, our understanding of the pathogenesis of inherited microcytic anemias has gained from the identification of several genes and proteins involved in systemic and cellular iron metabolism and heme syntheses. Numerous case reports illustrate that the implementation of these novel

  16. Study on the cause of iron-deficiency anemia in adolescent athletes by INAA with enriched stable isotopes

    International Nuclear Information System (INIS)

    Qian, Q.F.; Wu, S.Q.; Tian, J.B.; Huo, Z.P.; Chen, J.D.; Li, K.J.

    1991-01-01

    Iron deficiency anemia is still one of the most common nutritional deficiency diseases throughout the world. The incidence of iron deficiency is high especially in children, adolescent, and endurance athletes. The authors studied the iron absorption rate and iron balance in six child football players during training and non-training periods. The neutron activation method with enriched stable isotope 58Fe has been adopted. The results show that the rate of iron absorption in athletes during the training period (9.1 + 2.9%) was significantly lower than that during the non-training period (11.9 + 4.7%); the iron balance was negative and the sweat iron loss increased during training. Hair is one of the metabolism excretory organs. The physiological changes of body would influence the trace element contents in hair. The hairs collected from four athletes were measured by Synchrotron-induced X-ray Fluorescence analysis, so as to get the trace element contents. Preliminary results show that the changes of iron content in the hairs are in accordance with the athlete's physical activity. There are no perceptible changes for Zn and Ca. It is verified that exercise is one of the causes of iron deficiency in athletes. It is necessary to increase iron supply in an athletes' nutritional intake to ensure optimal performance ability

  17. Ferrokinetic studies in normal and iron deficiency anemic calves

    International Nuclear Information System (INIS)

    Moellerberg, L.; Ekman, L.; Jacobsson, S.-O.

    1975-01-01

    inetic studies were performed on control calves and on calves with experimentallally induced iron deficiency anemia, all 15 weeks old. The plasma iron clearance half time was about 4 times shorter in the experimental than in the control group. The low plasma iron concentration in the anemic calves was partially compensated by a more rapid plasma iron disappearance. Therefore the difference in the plasma iron turnover rate was reduced. The mean value of plasma iron renewal rate was about 3 times higher in the experimental than in the control group. The maximum uptake of injected 59 Fe into blood cells was reached 14 to 16 days after injection. The uptake of 59 Fe was about 10 % higher in the control than in the experimental group. Using the values from the ferrokinetietic study, the iron need for calves could be estimated. The requirement of iron to maintain a normal and constant Hb in a calf weighing 100 kg at a growth rate of 1 kg/daily was estimated as being 17.5 mg/day. Based on information in the literature and assuming a retention of dietary Fe of 25 %, the total daily iron need for such a calf gaining 1 kg/day would be 160-180 mg. (author)

  18. Effects of Radiation and Dietary Iron on Expression of Genes and Proteins Involved in Drug Metabolism

    Science.gov (United States)

    Faust, K. M.; Wotring, V. E.

    2014-01-01

    Liver function, especially the rate of metabolic enzyme activities, determines the concentration of circulating drugs and the duration of their efficacy. Most pharmaceuticals are metabolized by the liver, and clinically-used medication doses are given with normal liver function in mind. A drug overdose can result in the case of a liver that is damaged and removing pharmaceuticals from the circulation at a rate slower than normal. Alternatively, if liver function is elevated and removing drugs from the system more quickly than usual, it would be as if too little drug had been given for effective treatment. Because of the importance of the liver in drug metabolism, we want to understand any effects of spaceflight on the enzymes of the liver. Dietary factors and exposure to radiation are aspects of spaceflight that are potential oxidative stressors and both can be modeled in ground experiments. In this experiment, we examined the effects of high dietary iron and low dose gamma radiation (individually and combined) on the gene expression of enzymes involved in drug metabolism, redox homeostasis, and DNA repair. METHODS All procedures were approved by the JSC Animal Care and Use Committee. Male Sprague-Dawley rats were divided into 4 groups (n=8); control, high Fe diet (650 mg iron/kg), radiation (fractionated 3 Gy exposure from a Cs- 137 source) and combined high Fe diet + radiation exposure. Animals were euthanized 24h after the last treatment of radiation; livers were removed immediately and flash -frozen in liquid nitrogen. Expression of genes thought to be involved in redox homeostasis, drug metabolism and DNA damage repair was measured by RT-qPCR. Where possible, protein expression of the same genes was measured by western blotting. All data are expressed as % change in expression normalized to reference gene expression; comparisons were then made of each treatment group to the sham exposed/ normal diet control group. Data was considered significant at phigh Fe

  19. Moessbauer study of iron-sugar complexes

    International Nuclear Information System (INIS)

    Tonkovic, M.; Music, S.; Hadzija, O.; Nagy-Czako, I.; Vertes, A.

    1982-01-01

    Ferric-fructose complex has been prepared using FeCl 3 and Fe(NO 3 ) 3 solutions. Molecular weight determination and Moessbauer spectroscopic measurements proved that the ferric-fructose complex is polymeric in solid state and also in aqueous solution. The synthesis of a new iron-sorbose complex has been performed. Its Moessbauer spectra indicate a structure similar to that of the iron-fructose complex. (author)

  20. Studies of anisotropy of iron based superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, Jason A. [Iowa State Univ., Ames, IA (United States)

    2013-01-01

    To study the electronic anisotropy in iron based superconductors, the temperature dependent London penetration depth, Δλ(T), have been measured in several compounds, along with the angular dependent upper critical field, Hc2(T). Study was undertaken on single crystals of Ba(Fe1-xCox)2As2 with x=0.108 and x=0.127, in the overdoped range of the doping phase diagram, characterized by notable modulation of the superconducting gap. Heavy ion irradiation with matching field doses of 6 T and 6.5 T respectively, were used to create columnar defects and to study their effect on the temperature Δλ(T). The variation of the low-temperature penetration depth in both pristine and irradiated samples was fitted with a power-law function Δλ(T) = ATn. Irradiation increases the magnitude of the pre-factor A and decreases the exponent n, similar to the effect on the optimally doped samples. This finding supports the universal s ± scenario for the whole doping range.

  1. Toxicological studies and antimicrobial properties of some Iron(III ...

    African Journals Online (AJOL)

    Two iron(III) complexes of Ciprofloxacin were synthesized by reaction of the ligand with iron(III) chloride hexahydrate in different solutions. The nature of bonding of the ligands and the structure of the isolated metal complexes were elucidated on the basis of their physical and spectroscopic studies. The infrared spectra ...

  2. Effects of Omeprazole on Iron Absorption: Preliminary Study

    Directory of Open Access Journals (Sweden)

    Mahmut Yaşar Çeliker

    2013-09-01

    Full Text Available Objective: Increasing numbers of pediatric and adult patients are being treated with proton pump inhibitors (PPIs. PPIs are known to inhibit gastric acid secretion. Nonheme iron requires gastric acid for conversion to the ferrous form for absorption. Ninety percent of dietary and 100% of oral iron therapy is in the nonheme form. To the best of our knowledge, the effect of PPIs on iron absorption has not been studied in humans. Our study assessed the relationship between omeprazole therapy and iron absorption in healthy subjects. Materials and Methods: We recruited 9 healthy volunteers between June 2010 and March 2011. Subjects with chronic illness, anemia, or use of PPI therapy were excluded. Serum iron concentrations were measured 1, 2, and 3 h after the ingestion of iron (control group. The measurements were repeated on a subsequent visit after 4 daily oral administrations of omeprazole at a dose of 40 mg (treatment group. Results: One female and 8 male volunteers were enrolled in the study with a mean age of 33 years. There was no statistical difference detected between baseline, 1-h, 2-h, and 3-h iron levels between control and treatment groups. Conclusion: Administration of omeprazole for a short duration does not affect absorption of orally administered iron in healthy individuals.

  3. Changes in the proteomic and metabolic profiles of Beta vulgaris root tips in response to iron deficiency and resupply

    Directory of Open Access Journals (Sweden)

    Álvarez-Fernández Ana

    2010-06-01

    Full Text Available Abstract Background Plants grown under iron deficiency show different morphological, biochemical and physiological changes. These changes include, among others, the elicitation of different strategies to improve the acquisition of Fe from the rhizosphere, the adjustment of Fe homeostasis processes and a reorganization of carbohydrate metabolism. The application of modern techniques that allow the simultaneous and untargeted analysis of multiple proteins and metabolites can provide insight into multiple processes taking place in plants under Fe deficiency. The objective of this study was to characterize the changes induced in the root tip proteome and metabolome of sugar beet plants in response to Fe deficiency and resupply. Results Root tip extract proteome maps were obtained by 2-D isoelectric focusing polyacrylamide gel electrophoresis, and approximately 140 spots were detected. Iron deficiency resulted in changes in the relative amounts of 61 polypeptides, and 22 of them were identified by mass spectrometry (MS. Metabolites in root tip extracts were analyzed by gas chromatography-MS, and more than 300 metabolites were resolved. Out of 77 identified metabolites, 26 changed significantly with Fe deficiency. Iron deficiency induced increases in the relative amounts of proteins and metabolites associated to glycolysis, tri-carboxylic acid cycle and anaerobic respiration, confirming previous studies. Furthermore, a protein not present in Fe-sufficient roots, dimethyl-8-ribityllumazine (DMRL synthase, was present in high amounts in root tips from Fe-deficient sugar beet plants and gene transcript levels were higher in Fe-deficient root tips. Also, a marked increase in the relative amounts of the raffinose family of oligosaccharides (RFOs was observed in Fe-deficient plants, and a further increase in these compounds occurred upon short term Fe resupply. Conclusions The increases in DMRL synthase and in RFO sugars were the major changes induced by Fe

  4. The NIMO Scandinavian Study: A Prospective Observational Study of Iron Isomaltoside Treatment in Patients with Iron Deficiency

    Directory of Open Access Journals (Sweden)

    Svein Oskar Frigstad

    2017-01-01

    Full Text Available Background. Intravenous iron allows for efficient and well-tolerated treatment in iron deficiency and is routinely used in diseases of the gastrointestinal tract. Objective. The aims of this study were to determine the probability of relapse of iron deficiency over time and to investigate treatment routine, effectiveness, and safety of iron isomaltoside. Methods. A total of 282 patients treated with iron isomaltoside were observed for two treatments or a minimum of one year. Results. Out of 282 patients, 82 had Crohn’s disease and 67 had ulcerative colitis. Another 133 patients had chronic blood loss, malabsorption, or malignancy. Patients who received an iron isomaltoside dose above 1000 mg had a 65% lower probability of needing retreatment compared with those given 1000 mg. A clinically significant treatment response was shown, but in 71/191 (37% of patients, anaemia was not corrected. The mean dose given was 1100 mg, lower than the calculated total iron need of 1481 mg. Adverse drug reactions were reported in 4% of patients. Conclusion. Iron isomaltoside is effective with a good safety profile, and high doses reduce the need for retreatment over time. Several patients were anaemic after treatment, indicating that doses were inadequate for full iron correction. This trial is registered with NCT01900197.

  5. Neutron scattering study of yttrium iron garnet

    Science.gov (United States)

    Shamoto, Shin-ichi; Ito, Takashi U.; Onishi, Hiroaki; Yamauchi, Hiroki; Inamura, Yasuhiro; Matsuura, Masato; Akatsu, Mitsuhiro; Kodama, Katsuaki; Nakao, Akiko; Moyoshi, Taketo; Munakata, Koji; Ohhara, Takashi; Nakamura, Mitsutaka; Ohira-Kawamura, Seiko; Nemoto, Yuichi; Shibata, Kaoru

    2018-02-01

    The nuclear and magnetic structure and full magnon dispersions of yttrium iron garnet Y3Fe5O12 have been studied using neutron scattering. The refined nuclear structure is distorted to a trigonal space group of R 3 ¯ . The highest-energy dispersion extends up to 86 meV. The observed dispersions are reproduced by a simple model with three nearest-neighbor-exchange integrals between 16 a (octahedral) and 24 d (tetrahedral) sites, Ja a, Ja d, and Jd d, which are estimated to be 0.00 ±0.05 , -2.90 ±0.07 , and -0.35 ±0.08 meV, respectively. The lowest-energy dispersion below 14 meV exhibits a quadratic dispersion as expected from ferromagnetic magnons. The imaginary part of q -integrated dynamical spin susceptibility χ″(E ) exhibits a square-root energy dependence at low energies. The magnon density of state is estimated from χ″(E ) obtained on an absolute scale. The value is consistent with the single chirality mode for the magnon branch expected theoretically.

  6. Radiation absorbed doses from iron-52, iron-55, and iron-59 used to study ferrokinetics

    International Nuclear Information System (INIS)

    Robertson, J.S.; Price, R.R.; Budinger, T.F.; Fairbanks, V.F.; Pollycove, M.

    1983-01-01

    Biological data obtained principally with Fe-59 citrate are used with physical data to calculate radiation absorbed doses for ionic or weak chelate forms of Fe-52, Fe-55, and Fe-59, administered by intravenous injection. Doses are calculated for normal subjects, primary hemochromatosis (also called idiopathic or hereditary hemochromatosis), pernicious anemia in relapse, iron-deficiency anemia, and polycythemia vera. The Fe-52 doses include the dose from the Mn-52m daughter generated after injection of Fe-52. Special attention has been given to the dose to the spleen, which has a relatively high concentration of RBCs and therefore of radioiron, and which varies significantly in size in both health and disease

  7. Moessbauer spectroscopic studies of iron-storage proteins

    Energy Technology Data Exchange (ETDEWEB)

    St. Pierre, T.G.

    1986-01-01

    /sup 57/Fe Moessbauer spectroscopy was used to study iron storage proteins. Various cryostats and a superconducting magnet were used to obtain sample environment temperatures from 1.3 to 200K and applied magnetic fields of up to 10T. The Moessbauer spectra of ferritins isolated from iron-overloaded human spleen, limpet (Patella vulgata), giant limpet (Patella laticostata) and chiton (Clavarizona hirtosa) hemolymph, and bacterial (Pseudomonas aeruginosa) cells are used to gain information on the magnetic ordering- and superparamagnetic transition temperatures of the microcrystalline cores of the proteins. Investigations were made about the cause of the difference in the magnetic anisotropy constants of the cores of iron-overloaded human spleen ferritin and hemosiderin. Livers taken from an iron-overloaded hornbill and artificially iron-loaded rats showed no component with a superparamagnetic transition temperature approaching that of the human spleen hemosiderin.

  8. Metagenomic Study of Iron Homeostasis in Iron Depositing Hot Spring Cyanobacterial Community

    Science.gov (United States)

    Brown, I.; Franklin H.; Tringe, S. G.; Klatt, C. G.; Bryant, D. A.; Sarkisova, S. A.; Guevara, M.

    2010-01-01

    Introduction: It is not clear how an iron-rich thermal hydrosphere could be hospitable to cyanobacteria, since reduced iron appears to stimulate oxidative stress in all domains of life and particularly in oxygenic phototrophs. Therefore, metagenomic study of cyanobacterial community in iron-depositing hot springs may help elucidate how oxygenic prokaryotes can withstand the extremely high concentrations of reactive oxygen species (ROS) produced by interaction between environmental Fe2+ and O2. Method: Anchor proteins from various species of cyanobacteria and some anoxygenic phototrophs were selected on the basis of their hypothetical role in Fe homeostasis and the suppression of oxidative stress and were BLASTed against the metagenomes of iron-depositing Chocolate Pots and freshwater Mushroom hot springs. Results: BLASTing proteins hypothesized to be involved in Fe homeostasis against the microbiomes from the two springs revealed that iron-depositing hot spring has a greater abundance of defensive proteins such as bacterioferritin comigratory protein (Bcp) and DNA-binding Ferritin like protein (Dps) than a fresh-water hot spring. One may speculate that the abundance of Bcp and Dps in an iron-depositing hot spring is connected to the need to suppress oxidative stress in bacteria inhabiting environments with high Fe2+ concnetration. In both springs, Bcp and Dps are concentrated within the cyanobacterial fractions of the microbial community (regardless of abundance). Fe3+ siderophore transport (from the transport system permease protein query) may be less essential to the microbial community of CP because of the high [Fe]. Conclusion: Further research is needed to confirm that these proteins are unique to photoautotrophs such as those living in iron-depositing hot spring.

  9. Comparative study of efficacy, tolerability and compliance of oral iron preparations (iron edetate, iron polymatose complex) and intramuscular iron sorbitol in iron deficiency anaemia in children

    International Nuclear Information System (INIS)

    Afzal, M.; Qureshi, S.M.; Lutafullah, M.

    2009-01-01

    To compare the efficacy, tolerability and compliance of oral iron preparations(iron edetate and Iron polymaltose complex) with each other and with intramuscular iron sorbitol in iron deficiency anaemia in children. A Randomized Controlled Trial (RCT) was carried out at the Paediatric Department of Combined Military Hospital (CMH) from January 2006 to December 2007. In total 146 children, up to 12 years age having haemoglobin (Hb%) less than 8 gm% were included. They were randomly distributed into three groups. Group A(64 cases) received oral sodium iron edetate (SIE), Group B (40 cases) received oral iron polymaltose complex (IPC) and group C (42 cases) received intramuscular iron sorbitol (IS) in recommended dosages. Rise in Hb%>10 gm% was kept as desired target. Maximum duration of treatment planned was 2 weeks for parenteral iron (group C) and 12 weeks for oral iron (groups A and B). Haematological parameters- Hb%, mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH), mean corpuscular haemoglobin concentration (MCHC) were measured at induction followed at 2 weeks, 4 weeks, 8 weeks and 12 weeks after start of treatment. Compliance and drop out rates were determined on each visit. Data was analyzed using SPSS version 10. ANOVA was used to analyze difference in rise in Hb% at various intervals. Statistically significant increase in mean Hb%, MCV, MCHC after 02 weeks was observed in group C (IS). Rise in these parameters became significant in group A (SIE) and B (IPC) after 04 weeks. Persistent rise was observed in oral groups at 08 and 12 weeks. Rise in Hb% was much faster in group C (IS). It took 2 weeks to achieve mean Hb% > 10 gm% and compliance rate was 40.5%, while to achieve same target, duration required was 8 weeks in group A (SIE) and 12 weeks in group B (IPC) and compliance rate was 39% and 30% respectively. Adverse effects were much more common with group A (SIE) as compared to other two groups. Intramuscular iron sorbitol is a reliable and

  10. The challenge of defining and treating anemia and iron deficiency in pregnancy: A study of New Zealand midwives' management of iron status in pregnancy and the postpartum period.

    Science.gov (United States)

    Calje, Esther; Skinner, Joan

    2017-06-01

    Early recognition and management of low maternal iron status is associated with improved maternal, fetal, and neonatal outcomes. However, existing international guidelines for the testing and management of maternal iron-deficiency anemia are variable, with no national guideline for New Zealand midwives. Clinical management is complicated by normal physiological hemodilution, and complicated further by the effects of inflammation on iron metabolism, especially in populations with a high prevalence of obesity or infection. This study describes how midwives in one New Zealand area diagnose and treat anemia and iron deficiency, in the absence of established guidelines. Data on demographics, laboratory results, and documented clinical management were retrospectively collected from midwives (n=21) and women (n=189), from September to December 2013. Analysis was predominantly descriptive. A secondary analysis of iron status and body mass index (BMI) was undertaken. A total of 46% of 186 women, with hemoglobin testing at booking, did not have ferritin tested; 86% (of 385) of ferritin tests were not concurrently tested with C-reactive protein. Despite midwives prescribing iron for 48.7% of second trimester women, 47.1% still had low iron status before birth. Only 22.8% of women had hemoglobin testing postpartum. There was a significant difference between third trimester median ferritin levels in women with BMI ≥25.00 (14 μg/L) and BMI iron status was difficult to categorize, because of inconsistent testing. This study indicates the need for an evidence-based clinical guideline for New Zealand midwives and maternity care providers. © 2017 Wiley Periodicals, Inc.

  11. Influence of food tannins on certain aspects of iron metabolism : Part 1 -- Absorption and excretion in normal and anemic rats

    Energy Technology Data Exchange (ETDEWEB)

    Roy, S N [Albert Einstein Coll. of Medicine, Bronx, NY (USA); Mukher ee, S [Calcutta Univ. (India). Dept. of Applied Chemistry

    1979-04-01

    Studies on absorption and excretion of iron by isotopic and non-isotopic methods in normal and hemolytic anemic rats indicate that dietary food tannins at a dose of 0.5 mg/kg body wt/day tend to increase iron excretion in normal rats but more iron is absorbed or retained in tannin-fed anemic rats and absorption of iron is comparable to that in normal control. Both in vivo and in vitro tannin at a high dose (2.0 mg/kg body wt/day) inhibits the iron absorption in experimental animals. The interference of food tannins (0.5 kg/mg body wt/day) with absorption of iron (/sup 59/Fe) varies with plant species from which tannin has been prepared. Normal iron balance in tannin-fed (0.5 mg/kg body wt/day) anemic rats may result from increased assimilation of tannin-bound iron in intestinal mucosa, and absorbed tannin appears to remove unabsorbed iron.

  12. Increased iron availability resulting from increased CO2 enhances carbon and nitrogen metabolism in the economical marine red macroalga Pyropia haitanensis (Rhodophyta).

    Science.gov (United States)

    Chen, Binbin; Zou, Dinghui; Yang, Yufeng

    2017-04-01

    Ocean acidification caused by rising CO 2 is predicted to increase the concentrations of dissolved species of Fe(II) and Fe(III), leading to the enhanced photosynthetic carbon sequestration in some algal species. In this study, the carbon and nitrogen metabolism in responses to increased iron availability under two CO 2 levels (390 μL L -1 and 1000 μL L -1 ), were investigated in the maricultivated macroalga Pyropia haitanensis (Rhodophyta). The results showed that, elevated CO 2 increased soluble carbonhydrate (SC) contents, resulting from enhanced photosynthesis and photosynthetic pigment synthesis in this algae, but declined its soluble protein (SP) contents, resulting in increased ratio of SC/SP. This enhanced photosynthesis performance and carbon accumulation was more significant under iron enrichment condition in seawater, with higher iron uptake rate at high CO 2 level. As a key essential biogenic element for algae, Fe-replete functionally contributed to P. haitanensis photosynthesis. Increased SC fundamentally provided carbon skeletons for nitrogen assimilation. The significant increase of carbon and nitrogen assimilation finally contributed to enhanced growth in this alga. This was also intuitively reflected by respiration that provided energy for cellular metabolism and algal growth. We propose that, in the predicted scenario of rising atmospheric CO 2 , P. haitanensis is capable to adjust its physiology by increasing its carbon and nitrogen metabolism to acclimate the acidified seawater, at the background of global climate change and simultaneously increased iron concentration due to decreased pH levels. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Iron deficiency

    DEFF Research Database (Denmark)

    Schou, Morten; Bosselmann, Helle; Gaborit, Freja

    2015-01-01

    BACKGROUND: Both iron deficiency (ID) and cardiovascular biomarkers are associated with a poor outcome in heart failure (HF). The relationship between different cardiovascular biomarkers and ID is unknown, and the true prevalence of ID in an outpatient HF clinic is probably overlooked. OBJECTIVES.......043). CONCLUSION: ID is frequent in an outpatient HF clinic. ID is not associated with cardiovascular biomarkers after adjustment for traditional confounders. Inflammation, but not neurohormonal activation is associated with ID in systolic HF. Further studies are needed to understand iron metabolism in elderly HF...

  14. Changes in Serum Ferritin and Other Factors Associated with Iron Metabolism During Chronic Hyperbaric Exposure

    National Research Council Canada - National Science Library

    Gilman, Sara C; Hunter, Jr., W. L; Mooney, L. W

    1979-01-01

    .... during these simulated dives progressive and correlated increases in serum ferritin and iron occurred. No significant changes were observed in bilirubin, hemoglobin, neurloplasmia, transferrin, cooper, or total iron binding capacity...

  15. Moessbauer effect studies of magnetic interactions in iron and dilute iron alloys

    International Nuclear Information System (INIS)

    Woude, F. van der; Schurer, P.J.; Sawatzky, G.A.

    1975-01-01

    A temperature-dependent Moessbauer study was conducted in FeX alloys, where X = Al, Si, Ti, V, Cr, Mn, Co, and Ni, aimed at solving the problem of 'what is localized and what is itinerant in iron ferromagnetism'. The experimental results are interpreted using a phenomenological model based on a modified Zener-Vonsovskij theory. Absorption spectra of FeX alloys were measured as a function of temperature. It was found that the 3d magnetic moments in iron were mainly localized while exchange coupling was provided by partly itinerant 3d electrons. (L.D.)

  16. Effect of short-term food restriction on iron metabolism, relative well-being and depression symptoms in healthy women.

    Science.gov (United States)

    Wojciak, Rafal W

    2014-01-01

    The idea that iron deficiency anemia can be recognized in depressive patients has been around for a few years, as well as negative association between ferritin levels and depression. Iron deficiency anemia, associated with low iron intake, has been observed in women using restriction diets, for example in vegetarians or anorexics. There are no data on the influence of the short-term food restrictions, observed for example in slimming women, on iron management and its connection with behavior expressed via changes in the subject's emotional state. This study describes the effect of one- and two-day food restrictions (every 8 days for a period of 48 days) on selected iron management parameters in the serum and blood of 46 healthy volunteer women (23 in each group), aged 25.5 ± 3.0 years, in association with the subjects' self-described emotional status and depression symptoms. The association between iron parameters and depression was also analyzed. Results show that short-term (2 days) fasting significantly decreases iron concentrations in serum and hair, as well as levels of ferritin, hemoglobin, hematocrit, red blood cells, and total iron binding capacity, but the short-term fasting did not influence the other iron management parameters. Each model of food restrictions also increased negative feelings towards depression. A significant negative correlation between serum ferritin levels and depression was found in women who starved for 2 days. The study shows that, through an impact on mineral levels, even short-term food restrictions, as observed in many slimming women and girls, can be a reason for iron deficiency and also can alter the emotional status of healthy women. Maybe depression symptoms in anorexia or other eating disorders patients can be associated with iron deficiencies.

  17. Iron porphyrins doped sol-gel glasses: a chemometric study

    International Nuclear Information System (INIS)

    Sacco, Herica C.; Vidoto, Ednalva A.; Nascimento, Otaciro R.

    2000-01-01

    This paper describes the optimized conditions for preparation of iron porphyrin-template doped silica Fe PDS-template) obtained by the sol-gel process. The following porphyrins (Fe P) were used: Fe TFPP Cl, Fe TDCSPP(Na) 4 Cl and Fe TCPP(Na) 4 Cl. Pyridine or 4-phenylimidazole was used as template. The variables that present significant influence on iron porphyrin loading on xerogel were identified and the values that maximize the iron porphyrin loading on xerogel were established . The variables (Solvent volume, fractional factorial design in two levels, 2 5-1 type, generating 16 total experiments for each Fe P studied. (author)

  18. Iron porphyrins doped sol-gel glasses: a chemometric study

    Energy Technology Data Exchange (ETDEWEB)

    Sacco, Herica C.; Vidoto, Ednalva A.; Nascimento, Otaciro R. [Soap Paulo Univ (USP), Sao Carlos (Brazil). Inst. de Fisica; Biazzotto, Juliana C.; Serra, Osvaldo A.; Iamamoto, Yassuko [Sao Paulo Univ. (USP), Ribeirao Preto, SP (Brazil). Faculdade de Filosofia, Ciencias e Letras; Ciuffi, Katia J.; Mello, Cesar A.; Oliveira, Daniela C. de [Universidade de Franca , SP (Brazil)

    2000-07-01

    This paper describes the optimized conditions for preparation of iron porphyrin-template doped silica Fe (PDS-template) obtained by the sol-gel process. The following porphyrins (Fe P) were used: Fe TFPP Cl, Fe TDCSPP(Na){sub 4}Cl and Fe TCPP(Na){sub 4} Cl. Pyridine or 4-phenylimidazole was used as template. The variables that present significant influence on iron porphyrin loading on xerogel were identified and the values that maximize the iron porphyrin loading on xerogel were established. The variables Solvent volume, fractional factorial design in two levels, 2{sup 5-1} type, generating 16 total experiments for each Fe P studied. (author)

  19. Study of austempering reaction in austempered ductile iron

    International Nuclear Information System (INIS)

    Ja'far Farhan Al-Sharab; Sharma, D.G.R.; Samsul Bahar Sadli

    1996-01-01

    Austempered Ductile Iron (ADI) is an important engineering material which is gaining popularity. The conventional belief that austempered ductile iron, when heat treated satisfactorily, contains bainite, is now disproved by recent experiments. Our present work on the study of the reaction products of heat treated ADI by x-ray diffraction confirms the recent view. The results of x-ray diffraction studies on the structural constituents od ADI for various durations of austempering are presented and discussed

  20. Studies of anisotropy of iron based superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, Jason [Iowa State Univ., Ames, IA (United States)

    2013-01-01

    To study the electronic anisotropy in iron based superconductors, the temperature dependent London penetration depth, Δλ (T), have been measured in several compounds, along with the angular dependent upper critical field, Hc2(T). Study was undertaken on single crystals of Ba(Fe1-xCox)2As2 with x=0.108 and x=0.127, in the overdoped range of the doping phase diagram, characterized by notable modulation of the superconducting gap. Heavy ion irradiation with matching field doses of 6 T and 6.5 T respectively, were used to create columnar defects and to study their effect on the temperature Δλ (T). The variation of the low-temperature penetration depth in both pristine and irradiated samples was fitted with a power-law function Δλ (T) = ATn. Irradiation increases the magnitude of the pre-factor A and decreases the exponent n, similar to the effect on the optimally doped samples. This finding supports the universal s± scenario for the whole doping range. Knowing that the s± gap symmetry exists across the superconducting dome for the electron doped systems, we next looked at λ (T), in optimally - doped, SrFe2(As1-xPx)2, x =0.35. Both, as-grown (Tc ~ 25 K) and annealed (Tc ~ 35 K) single crystals of SrFe2(As1-xPx)2 were measured. Annealing decreases the absolute value of the London penetration depth from λ(0) = 300 ± 10 nm in as-grown samples to λ (0) = 275±10 nm. At low temperatures, λ (T) ~ T indicates a superconducting gap with line nodes. Analysis of the full-temperature range superfluid density is consistent with the line nodes, but differs from the simple single-gap d-wave. The observed behavior is very similar to that of BaFe2(As1-xPx)2, showing that isovalently substituted pnictides are inherently different from

  1. Study of the pyrophoric characteristics of uranium-iron alloys

    International Nuclear Information System (INIS)

    Duplessis, X.

    2000-01-01

    The objective of the study is to understand the pyrophoric characteristics of uranium-iron alloys. In order to carry out this research we have elected to use uranium-iron alloy powder with granules of 200 μm and 1000 μm diameter with 4%, 10.8% and 14% iron content. The experiments were performed on small samples of few milligrams and on larger quantities of few hundred grams. The main conclusions obtained are the followings: -The reaction start at 453 K (180 deg. C) and the ignition at 543 K (270 deg. C) - The influence of the specific area seems more important than the iron concentration in the alloys - When the alloy ignites, the fire spreads quickly and the alloy rapidly consumes. (author)

  2. Dietary iron intake, iron status, and gestational diabetes.

    Science.gov (United States)

    Zhang, Cuilin; Rawal, Shristi

    2017-12-01

    Pregnant women are particularly vulnerable to iron deficiency and related adverse pregnancy outcomes and, as such, are routinely recommended for iron supplementation. Emerging evidence from both animal and population-based studies, however, has raised potential concerns because significant associations have been observed between greater iron stores and disturbances in glucose metabolism, including increased risk of type 2 diabetes among nonpregnant individuals. Yet, the evidence is uncertain regarding the role of iron in the development of gestational diabetes mellitus (GDM), a common pregnancy complication which has short-term and long-term adverse health ramifications for both women and their children. In this review, we critically and systematically evaluate available data examining the risk of GDM associated with dietary iron, iron supplementation, and iron status as measured by blood concentrations of several indicators. We also discuss major methodologic concerns regarding the available epidemiologic studies on iron and GDM. © 2017 American Society for Nutrition.

  3. Moessbauer study of iron diffusion in beryllium

    International Nuclear Information System (INIS)

    Sepiol, B.; Ruebenbauer, K.; Miczko, B.; Birchall, T.

    1991-01-01

    The broadening of the 14.41 keV Moessbauer line of 57 Fe dure to diffusion of iron atoms in polycrystalline beryllium has been investigated in the temperature range 1123 to 1423 K. The observed broadenings obey the Arrhenius law with activation energy 1.66(10) eV, i.e., lower than that obtained from the corresponding polycrystalline tracer data. The variations of the resonant fraction, second order Doppler shift and quadrupole splitting versus temperature are reported. An average diffusion coefficient has been calculated from the obtained broadenings and compared with the tracer results. (orig.)

  4. Redox Balance in Lactobacillus reuteri DSM20016: Roles of Iron-Dependent Alcohol Dehydrogenases in Glucose/ Glycerol Metabolism.

    Directory of Open Access Journals (Sweden)

    Lu Chen

    Full Text Available Lactobacillus reuteri, a heterofermentative bacterium, metabolizes glycerol via a Pdu (propanediol-utilization pathway involving dehydration to 3-hydroxypropionaldehyde (3-HPA followed by reduction to 1,3-propandiol (1,3-PDO with concomitant generation of an oxidized cofactor, NAD+ that is utilized to maintain cofactor balance required for glucose metabolism and even for oxidation of 3-HPA by a Pdu oxidative branch to 3-hydroxypropionic acid (3-HP. The Pdu pathway is operative inside Pdu microcompartment that encapsulates different enzymes and cofactors involved in metabolizing glycerol or 1,2-propanediol, and protects the cells from the toxic effect of the aldehyde intermediate. Since L. reuteri excretes high amounts of 3-HPA outside the microcompartment, the organism is likely to have alternative alcohol dehydrogenase(s in the cytoplasm for transformation of the aldehyde. In this study, diversity of alcohol dehydrogenases in Lactobacillus species was investigated with a focus on L. reuteri. Nine ADH enzymes were found in L. reuteri DSM20016, out of which 3 (PduQ, ADH6 and ADH7 belong to the group of iron-dependent enzymes that are known to transform aldehydes/ketones to alcohols. L. reuteri mutants were generated in which the three ADHs were deleted individually. The lagging growth phenotype of these deletion mutants revealed that limited NAD+/NADH recycling could be restricting their growth in the absence of ADHs. Notably, it was demonstrated that PduQ is more active in generating NAD+ during glycerol metabolism within the microcompartment by resting cells, while ADH7 functions to balance NAD+/NADH by converting 3-HPA to 1,3-PDO outside the microcompartment in the growing cells. Moreover, evaluation of ADH6 deletion mutant showed strong decrease in ethanol level, supporting the role of this bifuctional alcohol/aldehyde dehydrogenase in ethanol production. To the best of our knowledge, this is the first report revealing both internal and

  5. Formation of poorly crystalline iron monosulfides: Surface redox reactions on high purity iron, spectroelectrochemical studies

    Energy Technology Data Exchange (ETDEWEB)

    Hansson, E.B. [Geological Institute, University of Copenhagen, Oster Voldgade 10, Copenhagen K, DK-1350 (Denmark); Odziemkowski, M.S. [Department of Earth Sciences, University of Waterloo, Waterloo, Ont., N2L 3G1 (Canada)]. E-mail: marek@sciborg.uwaterloo.ca; Gillham, R.W. [Department of Earth Sciences, University of Waterloo, Waterloo, Ont., N2L 3G1 (Canada)

    2006-11-15

    In the use of iron for reductive dehalogenation of chlorinated solvents in ground water, due to presence of sulfate-reducing bacteria the formation of hydrogen sulfide is expected. To simulate those processes the interface between 99.99% pure iron and 0.1 M NaHCO{sub 3} deoxygenated solution with 3.1 x 10{sup -5}-7.8 x 10{sup -3} M Na{sub 2}S . 9H{sub 2}O added was studied. The surface processes were characterised by the in situ normal Raman spectroscopy (NRS) and ex situ techniques; X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), energy dispersive X-ray (EDX). The open circuit potential (OCP) was monitored during in situ NRS measurements, and potentiodynamic anodic polarization measurements were carried out to reveal electrochemical behaviour of iron electrode. Open circuit potential-time transients indicated that the native oxide is unstable in deaerated bicarbonate solution and undergoes reductive dissolution (i.e. autoreduction) leaving the metallic Fe covered by Fe(OH){sub 2}, adsorbed OH{sup -}, and patches of 'magnetite-like' oxide. Immediately upon injection of the Na{sub 2}S-solution the iron interface undergoes complex redox surface processes and a poorly crystalline FeS film forms. Potentiodynamic anodic polarization measurements indicated a mechanical breakdown of the FeS film. The origin and initiation of this breakdown process is not clear but is probably a result of internal stress developed during film growth. Based on surface studies supported by electrochemical measurements, a conceptual model for the complex redox processes occurring at the iron interface is proposed. This model describes the structural development of a poorly crystalline FeS, which breaks down, allowing further dissolution of the Fe and formation of FeOOH at the interface. Simultaneously and despite the existence of thick layer of FeS the entrance of hydrogen was evident as the typical hydrogen cracks in bulk of the

  6. Genome Analysis of the Biotechnologically Relevant Acidophilic Iron Oxidising Strain JA12 Indicates Phylogenetic and Metabolic Diversity within the Novel Genus "Ferrovum".

    Directory of Open Access Journals (Sweden)

    Sophie R Ullrich

    Full Text Available Members of the genus "Ferrovum" are ubiquitously distributed in acid mine drainage (AMD waters which are characterised by their high metal and sulfate loads. So far isolation and microbiological characterisation have only been successful for the designated type strain "Ferrovum myxofaciens" P3G. Thus, knowledge about physiological characteristics and the phylogeny of the genus "Ferrovum" is extremely scarce.In order to access the wider genetic pool of the genus "Ferrovum" we sequenced the genome of a "Ferrovum"-containing mixed culture and successfully assembled the almost complete genome sequence of the novel "Ferrovum" strain JA12.The genome-based phylogenetic analysis indicates that strain JA12 and the type strain represent two distinct "Ferrovum" species. "Ferrovum" strain JA12 is characterised by an unusually small genome in comparison to the type strain and other iron oxidising bacteria. The prediction of nutrient assimilation pathways suggests that "Ferrovum" strain JA12 maintains a chemolithoautotrophic lifestyle utilising carbon dioxide and bicarbonate, ammonium and urea, sulfate, phosphate and ferrous iron as carbon, nitrogen, sulfur, phosphorous and energy sources, respectively.The potential utilisation of urea by "Ferrovum" strain JA12 is moreover remarkable since it may furthermore represent a strategy among extreme acidophiles to cope with the acidic environment. Unlike other acidophilic chemolithoautotrophs "Ferrovum" strain JA12 exhibits a complete tricarboxylic acid cycle, a metabolic feature shared with the closer related neutrophilic iron oxidisers among the Betaproteobacteria including Sideroxydans lithotrophicus and Thiobacillus denitrificans. Furthermore, the absence of characteristic redox proteins involved in iron oxidation in the well-studied acidophiles Acidithiobacillus ferrooxidans (rusticyanin and Acidithiobacillus ferrivorans (iron oxidase indicates the existence of a modified pathway in "Ferrovum" strain JA12

  7. Results of the First American Prospective Study of Intravenous Iron in Oral Iron-Intolerant Iron-Deficient Gravidas.

    Science.gov (United States)

    Auerbach, Michael; James, Stephanie E; Nicoletti, Melissa; Lenowitz, Steven; London, Nicola; Bahrain, Huzefa F; Derman, Richard; Smith, Samuel

    2017-12-01

    Anemia affects up to 42% of gravidas. Neonatal iron deficiency is associated with low birth weight, delayed growth and development, and increased cognitive and behavioral abnormalities. While oral iron is convenient, up to 70% report significant gastrointestinal toxicity. Intravenous iron formulations allowing replacement in one visit with favorable side-effect profiles decrease rates of anemia with improved hemoglobin responses and maternal fetal outcomes. Seventy-four oral iron-intolerant, second- and third-trimester iron-deficient gravidas were questioned for oral iron intolerance and treated with intravenous iron. All received 1000 mg of low-molecular-weight iron dextran in 250 mL normal saline. Fifteen minutes after a test dose, the remainder was infused over the balance of 1 hour. Subjects were called at 1, 2, and 7 days to assess delayed reactions. Four weeks postinfusion or postpartum, hemoglobin levels and iron parameters were measured. Paired t test was used for hemoglobin and iron; 58/73 women were questioned about interval growth and development of their babies. Seventy-three of 74 enrolled subjects completed treatment. Sixty had paired pre- and posttreatment data. The mean pre- and posthemoglobin concentrations were 9.7 and 10.8 g/dL (P iron deficiency anemia. Intravenous iron has less toxicity and is more effective, supporting moving it closer to frontline therapy. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Moessbauer study of iron uptake in cucumber root

    Energy Technology Data Exchange (ETDEWEB)

    Kovacs, K.; Kuzmann, E., E-mail: kuzmann@para.chem.elte.hu [Eoetvoes Lorand University, Research Group for Nuclear Methods in Structural Chemistry, Hungarian Academy of Sciences, Department of Nuclear Chemistry (Hungary); Fodor, F. [Eoetvoes Lorand University, Department of Plant Physiology and Molecular Plant Biology (Hungary); Vertes, A. [Eoetvoes Lorand University, Research Group for Nuclear Methods in Structural Chemistry, Hungarian Academy of Sciences, Department of Nuclear Chemistry (Hungary); Kamnev, A. A. [Russian Academy of Sciences, Institute of Biochemistry and Physiology of Plants and Microorganisms (Russian Federation)

    2005-09-15

    {sup 57}Fe Moessbauer spectroscopy was used to study the uptake and distribution of iron in the root of cucumber plants grown in iron-deficient modified Hoagland nutrient solution and put into iron-containing solution with 10 {mu}M Fe citrate enriched with {sup 57}Fe (90%) only before harvesting. The Moessbauer spectra of the frozen roots exhibited two Fe{sup 3+} components with typical average Moessbauer parameters of {delta} = 0.5 mm s{sup -1}, {Delta} = 0.46 mm s{sup -1} and {delta} = 0.5 mm s{sup -1}, {Delta} = 1.2 mm s{sup -1} at 78 K and the presence of an Fe{sup 2+} doublet, assigned to the ferrous hexaaqua complex. This finding gives a direct evidence for the existence of Fe{sup 2+} ions produced via root-associated reduction according to the mechanism proposed for iron uptake for dicotyledonous plants. Monotonous changes in the relative content of the components were found with the time period of iron supply. The Moessbauer results are interpreted in terms of iron uptake and transport through the cell wall and membranes.

  9. Wearing red for signaling: the heme-bach axis in heme metabolism, oxidative stress response and iron immunology.

    Science.gov (United States)

    Igarashi, Kazuhiko; Watanabe-Matsui, Miki

    2014-04-01

    The connection between gene regulation and metabolism is an old issue that warrants revisiting in order to understand both normal as well as pathogenic processes in higher eukaryotes. Metabolites affect the gene expression by either binding to transcription factors or serving as donors for post-translational modification, such as that involving acetylation and methylation. The focus of this review is heme, a prosthetic group of proteins that includes hemoglobin and cytochromes. Heme has been shown to bind to several transcription factors, including Bach1 and Bach2, in higher eukaryotes. Heme inhibits the transcriptional repressor activity of Bach1, resulting in the derepression of its target genes, such as globin in erythroid cells and heme oxygenase-1 in diverse cell types. Since Bach2 is important for class switch recombination and somatic hypermutation of immunoglobulin genes as well as regulatory and effector T cell differentiation and the macrophage function, the heme-Bach2 axis may regulate the immune response as a signaling cascade. We discuss future issues regarding the topic of the iron/heme-gene regulation network based on current understanding of the heme-Bach axis, including the concept of "iron immunology" as the synthesis of the iron metabolism and the immune response.

  10. Genome-wide association study identifies genetic loci associated with iron deficiency.

    Directory of Open Access Journals (Sweden)

    Christine E McLaren

    2011-03-01

    Full Text Available The existence of multiple inherited disorders of iron metabolism in man, rodents and other vertebrates suggests genetic contributions to iron deficiency. To identify new genomic locations associated with iron deficiency, a genome-wide association study (GWAS was performed using DNA collected from white men aged≥25 y and women≥50 y in the Hemochromatosis and Iron Overload Screening (HEIRS Study with serum ferritin (SF≤12 µg/L (cases and iron replete controls (SF>100 µg/L in men, SF>50 µg/L in women. Regression analysis was used to examine the association between case-control status (336 cases, 343 controls and quantitative serum iron measures and 331,060 single nucleotide polymorphism (SNP genotypes, with replication analyses performed in a sample of 71 cases and 161 controls from a population of white male and female veterans screened at a US Veterans Affairs (VA medical center. Five SNPs identified in the GWAS met genome-wide statistical significance for association with at least one iron measure, rs2698530 on chr. 2p14; rs3811647 on chr. 3q22, a known SNP in the transferrin (TF gene region; rs1800562 on chr. 6p22, the C282Y mutation in the HFE gene; rs7787204 on chr. 7p21; and rs987710 on chr. 22q11 (GWAS observed P<1.51×10(-7 for all. An association between total iron binding capacity and SNP rs3811647 in the TF gene (GWAS observed P=7.0×10(-9, corrected P=0.012 was replicated within the VA samples (observed P=0.012. Associations with the C282Y mutation in the HFE gene also were replicated. The joint analysis of the HEIRS and VA samples revealed strong associations between rs2698530 on chr. 2p14 and iron status outcomes. These results confirm a previously-described TF polymorphism and implicate one potential new locus as a target for gene identification.

  11. Serum-ferritin and iron absorption for the study of body iron stored in the Thai population

    International Nuclear Information System (INIS)

    Plehachinda, R.

    1984-05-01

    Measurements of serum ferritin by an ''in-house'' immunoradiometric assay (IRMA) method were used in conjunction with estimations of gastro-intestinal iron absorption from a standard test dose of ferrous ascorbate, measurements of blood haemoglobin and measurements of other haematological parameters to study body iron status in various population groups and to assess changes in body iron status after food-iron fortification. The IRMA method particularly covered the lower range of serum ferritin levels from 0.5 to 10 μg/litre, corresponding to iron deficiency. Quality control indicated satisfactory assay performance. In preliminary studies, serum ferritin level was found to be well correlated with gastro-intestinal iron absorption as an indicator of body iron status. Normal adult male subjects in Bangkok showed levels of 21-314 μg/litre and normal adult female levels of 13-173 μg/litre, in general agreement with values reported by other authors. Measurements were then extended to subjects in an area of north-eastern Thailand where iron-deficiency was common, to assess the effectiveness of food-iron fortification programmes. Measurements were also made on male blood donors in Bangkok, pregnant female subjects in Bangkok and north-eastern Thailand, school children in an area of southern Thailand where hookworm infestation was common and schoolchildren and adult female subjects in an area of northern Thailand where goitre was endemic. The results of all these studies are presented

  12. Iron metabolism in mynah birds (Gracula religiosa) resembles human hereditary haemochromatosis

    NARCIS (Netherlands)

    Mete, A; Hendriks, HG; Klaren, PHM; Dorrestein, GM; van Dijk, JE; Marx, JJM

    2003-01-01

    Iron overload is a very frequent finding in several animal species and a genetic predisposition is suggested. In one of the most commonly reported species with susceptibility for iron overload ( mynah bird), it was recently shown that the cause of this pathophysiology is high uptake and retention of

  13. The effect of iron and/or lactose on strontium metabolism in neonatal and weanling rats

    International Nuclear Information System (INIS)

    Gruden, N.; Mataushicj, S.

    1988-01-01

    Iron-fortified cow's milk increased strontium-85 retention in the femur and brain of neonatal rats by 16-44%, irrespective of the presence or absence of lactose. A similar effect was observed in the brain of weaning rats if milk was enriched with lactose and was not altered by simultaneous addition of iron. (author). 18 refs.; 1 tab

  14. Iron Depletion and Repletion with Ferrous Sulfate or Electrolytic Iron Modifies the Composition and Metabolic Activity of the Gut Microbiota in Rats

    NARCIS (Netherlands)

    Dostal, A.; Chassard, C.; Hilty, F.M.; Zimmermann, M.B.; Jaeggi, T.; Rossi, S.; Lacroix, C.

    2012-01-01

    Iron (Fe) deficiency anemia is a global health concern and Fe fortification and supplementation are common corrective strategies. Fe is essential not only for the human host but also for nearly all gut bacteria. We studied the impact of Fe deficiency and Fe repletion on the gut microbiota in rats.

  15. Iron prophylaxis during pregnancy -- how much iron is needed? A randomized dose- response study of 20-80 mg ferrous iron daily in pregnant women

    DEFF Research Database (Denmark)

    Milman, Nils; Bergholt, Thomas; Eriksen, Lisbeth

    2005-01-01

    To determine the lowest dose of iron preventative of iron deficiency and iron deficiency anemia in pregnancy.......To determine the lowest dose of iron preventative of iron deficiency and iron deficiency anemia in pregnancy....

  16. A TEM Study on the Ti-Alloyed Grey Iron

    DEFF Research Database (Denmark)

    Moumeni, Elham; Tiedje, Niels Skat; Grumsen, Flemming Bjerg

    2014-01-01

    The microstructure of graphite flakes in titanium alloyed cast iron is studied using electron microscopy techniques. Dual beam SEM/FIB has been used for TEM sample preparation. A TEM study has been carried out on graphite flakes in grey cast iron using selected area electron diffraction. Based...... and that there is a high proportion of twins in the fine grained graphite. It appears that twinning and stacking faults are involved in the fine grained structure of the graphite. It is discussed how Ti addition affect crystal growth and may lead to formation of superfine graphite....

  17. Clearance of iron oxide particles in rat liver: effect of hydrated particle size and coating material on liver metabolism.

    Science.gov (United States)

    Briley-Saebo, Karen C; Johansson, Lars O; Hustvedt, Svein Olaf; Haldorsen, Anita G; Bjørnerud, Atle; Fayad, Zahi A; Ahlstrom, Haakan K

    2006-07-01

    We sought to evaluate the effect of the particle size and coating material of various iron oxide preparations on the rate of rat liver clearance. The following iron oxide formulations were used in this study: dextran-coated ferumoxide (size = 97 nm) and ferumoxtran-10 (size = 21 nm), carboxydextran-coated SHU555A (size = 69 nm) and fractionated SHU555A (size = 12 nm), and oxidized-starch coated materials either unformulated NC100150 (size = 15 nm) or formulated NC100150 injection (size = 12 nm). All formulations were administered to 165 rats at 2 dose levels. Quantitative liver R2* values were obtained during a 63-day time period. The concentration of iron oxide particles in the liver was determined by relaxometry, and these values were used to calculate the particle half-lives in the liver. After the administration of a high dose of iron oxide, the half-life of iron oxide particles in rat liver was 8 days for dextran-coated materials, 10 days for carboxydextran materials, 14 days for unformulated oxidized-starch, and 29 days for formulated oxidized-starch. The results of the study indicate that materials with similar coating but different sizes exhibited similar rates of liver clearance. It was, therefore, concluded that the coating material significantly influences the rate of iron oxide clearance in rat liver.

  18. Genome Analysis of the Biotechnologically Relevant Acidophilic Iron Oxidising Strain JA12 Indicates Phylogenetic and Metabolic Diversity within the Novel Genus “Ferrovum”

    Science.gov (United States)

    Ullrich, Sophie R.; Poehlein, Anja; Tischler, Judith S.; González, Carolina; Ossandon, Francisco J.; Daniel, Rolf; Holmes, David S.; Schlömann, Michael; Mühling, Martin

    2016-01-01

    Background Members of the genus “Ferrovum” are ubiquitously distributed in acid mine drainage (AMD) waters which are characterised by their high metal and sulfate loads. So far isolation and microbiological characterisation have only been successful for the designated type strain “Ferrovum myxofaciens” P3G. Thus, knowledge about physiological characteristics and the phylogeny of the genus “Ferrovum” is extremely scarce. Objective In order to access the wider genetic pool of the genus “Ferrovum” we sequenced the genome of a “Ferrovum”-containing mixed culture and successfully assembled the almost complete genome sequence of the novel “Ferrovum” strain JA12. Phylogeny and Lifestyle The genome-based phylogenetic analysis indicates that strain JA12 and the type strain represent two distinct “Ferrovum” species. “Ferrovum” strain JA12 is characterised by an unusually small genome in comparison to the type strain and other iron oxidising bacteria. The prediction of nutrient assimilation pathways suggests that “Ferrovum” strain JA12 maintains a chemolithoautotrophic lifestyle utilising carbon dioxide and bicarbonate, ammonium and urea, sulfate, phosphate and ferrous iron as carbon, nitrogen, sulfur, phosphorous and energy sources, respectively. Unique Metabolic Features The potential utilisation of urea by “Ferrovum” strain JA12 is moreover remarkable since it may furthermore represent a strategy among extreme acidophiles to cope with the acidic environment. Unlike other acidophilic chemolithoautotrophs “Ferrovum” strain JA12 exhibits a complete tricarboxylic acid cycle, a metabolic feature shared with the closer related neutrophilic iron oxidisers among the Betaproteobacteria including Sideroxydans lithotrophicus and Thiobacillus denitrificans. Furthermore, the absence of characteristic redox proteins involved in iron oxidation in the well-studied acidophiles Acidithiobacillus ferrooxidans (rusticyanin) and Acidithiobacillus

  19. Tumor-initiating cells of breast and prostate origin show alterations in the expression of genes related to iron metabolism

    Czech Academy of Sciences Publication Activity Database

    Rychtarčíková, Zuzana; Lettlová, Sandra; Tomkova, Veronika; Korenková, Vlasta; Langerová, Lucie; Simonova, Ekaterina; Zjablovskaja, Polina; Alberich-Jorda, Meritxell; Neužil, Jiří; Truksa, Jaroslav

    2017-01-01

    Roč. 8, č. 4 (2017), s. 6376-6398 ISSN 1949-2553 R&D Projects: GA ČR GA13-28830S; GA ČR GA15-03796S; GA MŠk(CZ) ED1.1.00/02.0109 Institutional support: RVO:86652036 ; RVO:68378050 Keywords : tumor-initiating cells * breast cancer * iron metabolism Subject RIV: FD - Oncology ; Hematology; EB - Genetics ; Molecular Biology (UMG-J) OBOR OECD: Cell biology; Cell biology (UMG-J) Impact factor: 5.168, year: 2016

  20. The role of p97 in iron metabolism in human brain glioma cells

    International Nuclear Information System (INIS)

    Xia Chunlin; Chen Guiwen; Qian Zhongming

    2000-01-01

    Objective: To investigate the role of p97 (melanotransferrin) in iron uptake in human brain glioma cells . Methods: Human brain glioma cell lines, GBM and BT325 were incubated in the medium containing 59 Fe-Citrate. The cells were treated with phosphatidylinositol-phospholipase C (PI-PLC) and pronase. The iron uptake of the cells was expressed as relative iron uptake level according to the cpm measured by the gamma scintillation counter. Results: 59 Fe uptake of the cells was significantly declined with the certain concentration of PI-PCL. 59 Fe uptake of the cells treated with pronase tended to coincide with that of the cells treated without pronase in the increasing concentration of PI-PLC. Conclusion: p97 expresses a high level and plays an important role in iron uptake in human brain glioma cells

  1. studies on iron availability in Egyptian soils using tracer technique

    International Nuclear Information System (INIS)

    Gad allah, A.M.A.

    1984-01-01

    four experiments were conducted to study the available fe in some egyptian soils, representing alluvial,, calcareous, and sandy soils, including the following:1) estimation of soil available iron using different chemical methods as well as E-value and evaluated against biological method. 2) differentiation of iron as Fe 2+ and Fe 2+ in some selected egyptian soils by using the modified method (charlot,1966). 3) determination of total Fe in soil using neutron activation analysis. 4) the relative importance of Fe-diffusion in egyptian soils under different treatments

  2. Changes in Serum Ferritin and Other Factors Associated with Iron Metabolism During Chronic Hyperbaric Exposure

    Science.gov (United States)

    1979-03-01

    tech- jects prior to their participation included standard radio- ques , using- radioisotopes ("SFe and S"Tcm-- diphospho- graphic surveys for evidence of... es were apparent by the third dive day for iron and the iv than ABN. It is of interest that no VGE were heard ajt seventh dive day for ferrtin. No...source of the increased amounts of ferritin levels in acute bepatocellular damage from serum ferritin and iron found during these dives ap.- paracetamol

  3. Iron metabolism in experimental rickets. Pt. 2. Pharmacological investigations on ferrokinetics in rat rickets

    International Nuclear Information System (INIS)

    Pronicka, E.

    1975-01-01

    Investigations of ferrokinetics were performed using 59 Fe isotope in experimental rickets. It was found that rickets does not cause in rats detectable changes in plasma iron turnover and in the half-time of iron clearance from the plasma. Only a transient impairment of iron utilization by the erythrocytes of rats with rickets was observed. In the blood cell counts no differences were revealed. Besides that a lower weight of the liver and a higher weight of the spleen were observed in rats with rickets as compared with controls. These organs showed a different degree of 59 Fe deposition after a single intravenous dose between both groups. No differences were found in the liver iron stores expressed as the level of non-heme iron. On the basis of the obtained results and data from the literature the author suggests the possibility of changes in the absorption of iron by the reticulo-endothelial system in rickets. In severe osseous changes caused by rickets a transient inhibition of erythropoiesis is possible. (author)

  4. Effects of dietary heme iron and exercise training on abdominal fat accumulation and lipid metabolism in high-fat diet-fed mice.

    Science.gov (United States)

    Katsumura, Masanori; Takagi, Shoko; Oya, Hana; Tamura, Shohei; Saneyasu, Takaoki; Honda, Kazuhisa; Kamisoyama, Hiroshi

    2017-08-01

    Animal by-products can be recycled and used as sources of essential nutrients. Water-soluble heme iron (WSHI), a functional food additive for supplementing iron, is produced by processing animal blood. In this study, we investigated the effects of dietary supplementation of 3% WSHI and exercise training for 4 weeks on the accumulation of abdominal fat and lipid metabolism in mice fed high-fat diet. Exercise-trained mice had significantly less perirenal adipose tissue, whereas WSHI-fed mice tended to have less epididymal adipose tissue. In addition, total weight of abdominal adipose tissues was significantly decreased in the Exercise + WSHI group. Dietary WSHI significantly increased the messenger RNA (mRNA) levels of lipoprotein lipase and hormone-sensitive lipase. WSHI-fed mice also tended to show increased mRNA levels of adipose triglyceride lipase in their epididymal adipose tissue. Dietary WSHI also significantly decreased the mRNA levels of fatty acid oxidation-related enzymes in the liver, but did not influence levels in the Gastrocnemius muscle. Exercise training did not influence the mRNA levels of lipid metabolism-related enzymes in the epididymal adipose tissue, liver or the Gastrocnemius muscle. These findings suggest that the accumulation of abdominal fat can be efficiently decreased by the combination of dietary WSHI and exercise training in mice fed high-fat diet. © 2016 Japanese Society of Animal Science.

  5. Kinetic, spectroscopic and chemical modification study of iron release from transferrin; iron(III) complexation to adenosine triphosphate

    International Nuclear Information System (INIS)

    Thompson, C.P.

    1985-01-01

    Amino acids other than those that serve as ligands have been found to influence the chemical properties of transferrin iron. The catalytic ability of pyrophosphate to mediate transferrin iron release to a terminal acceptor is largely quenched by modification non-liganded histine groups on the protein. The first order rate constants of iron release for several partially histidine modified protein samples were measured. A statistical method was employed to establish that one non-liganded histidine per metal binding domain was responsible for the reduction in rate constant. These results imply that the iron mediated chelator, pyrophosphate, binds directly to a histidine residue on the protein during the iron release process. EPR spectroscopic results are consistent with this interpretation. Kinetic and amino acid sequence studies of ovotransferrin and lactoferrin, in addition to human serum transferrin, have allowed the tentative assignment of His-207 in the N-terminal domain and His-535 in the C-terminal domain as the groups responsible for the reduction in rate of iron release. The above concepts have been extended to lysine modified transferrin. Complexation of iron(II) to adenosine triphosphate (ATP) was also studied to gain insight into the nature of iron-ATP species present at physiological pH. 31 P NMR spectra are observed when ATP is presented in large excess

  6. Theoretical Study of Spin Crossover in 30 Iron Complexes

    DEFF Research Database (Denmark)

    Kepp, Kasper Planeta

    2016-01-01

    Spin crossover was studied in 30 iron complexes using density functional theory to quantify the direction and magnitude of dispersion, relativistic effects, zero-point energies, and vibrational entropy. Remarkably consistent entropy−enthalpy compensation was identified. Zero-point energies favor...

  7. Magnetic and quadrupolar studies of the iron storage overload in livers

    International Nuclear Information System (INIS)

    Rimbert, J.N.; Dumas, F.; Richardot, G.; Kellershohn, C.

    1986-01-01

    Absorption 57 Fe Moessbauer spectra, performed directly on tissues of liver with iron overload due to an excessive intestinal iron absorption or induced by hypertransfusional therapeutics, have pointed out a new high spin ferric storage iron besides the ferritin and hemosiderin. Moessbauer studies, carried out on ferritin and hemosiderin fractions isolated from normal and overloaded livers, show that this compound, only present in the secondary iron overload (transfusional pathway), seems characteristic of the physiological process which induces the iron overload. (Auth.)

  8. Moessbauer and positron annihilation studies of microstructural peculiarities of iron-dextran complexes

    International Nuclear Information System (INIS)

    Oshtrakh, M.I.; Kopelyan, E.A.; Semionkin, V.A.; Livshits, A.B.; Kozlov, A.A.

    1995-01-01

    The microstructural peculiarities of pharmaceutically important iron-dextran complexes were studied by Moessbauer and positron annihilation techniques. The results of Moessbauer spectroscopy showed variations of the iron cores in iron-dextran complexes containing different forms of FeOOH and different electronic and magnetic states of iron. The results of angular correlations of annihilation radiation and positron life-time spectroscopies showed microstructural variations of the dextran shell of the iron-dextran complexes. (author) 19 refs.; 4 tabs

  9. Kinetic Study of Iron (III) Salicyl Hydroxamate Complexes

    International Nuclear Information System (INIS)

    Ali, K.; Ashiq, U.; Ara, R.; Kazmi, R.

    2005-01-01

    The formation of Salicylhydroxamic acid iron (III) complexes were studied at different pH. The reaction at pH 8 and 6 between iron nitrate and salicylhydroxamic acid is very fast and reddish brown colour with iron at 425 nm appears within seconds i.e. within mixing time. The concentration of salicylhydroxamic acid was 20-80 times higher than the concentration of iron (III) solution in order to fulfill pseudo first order conditions. The reddish brown colour appears within mixing time and further change in colour was very slow and observed at 425 nm wave length. The rate constant at pH 8 is 0.1886 sec and at pH 6 is 1.472 sec. The sharp appearance of colour is due to formation of 1:1 and 1:2 complexes while the observed slow change in colour may be due to rearrangement of salicylhydroxamic acid from bidentate to tridentate or it may be due to the formation of 1:3 complex. In the next set of reactions the 1:1 complex of salicylhydroxamic acid iron (III) was prepared by mixing iron (III) and salicylhydroxamic acid in 1:1 mole ratio and then the formation of 1:2 complex was observed at pH 5, 4.5 and 4. The concentration of salicylhydroxamic acid solution was 2-10 times higher than the 1:1 complex of salicylhydroxamic acid iron (III) complex. The observed reactions were very fast and were not truly a first order reaction. The rate constant is 24.85 sec at pH 4.5 and 16.98 sec at pH4. The reaction of 1:1 complex with salicylhydroxamic acid at pH3 was very fast. The lamda max of iron complex is 500 nm and of final mixture is 476 nm. The reaction was assumed to be reversible. The absorbance of both species at a particular wavelength is additive. Using this property the equilibrium constant was calculated which was not constant at different ratios of 1:1 complex and salicylhydroxamic acid, which further indicate the possibility of rearrangement reaction. (author)

  10. Sample size calculation in metabolic phenotyping studies.

    Science.gov (United States)

    Billoir, Elise; Navratil, Vincent; Blaise, Benjamin J

    2015-09-01

    The number of samples needed to identify significant effects is a key question in biomedical studies, with consequences on experimental designs, costs and potential discoveries. In metabolic phenotyping studies, sample size determination remains a complex step. This is due particularly to the multiple hypothesis-testing framework and the top-down hypothesis-free approach, with no a priori known metabolic target. Until now, there was no standard procedure available to address this purpose. In this review, we discuss sample size estimation procedures for metabolic phenotyping studies. We release an automated implementation of the Data-driven Sample size Determination (DSD) algorithm for MATLAB and GNU Octave. Original research concerning DSD was published elsewhere. DSD allows the determination of an optimized sample size in metabolic phenotyping studies. The procedure uses analytical data only from a small pilot cohort to generate an expanded data set. The statistical recoupling of variables procedure is used to identify metabolic variables, and their intensity distributions are estimated by Kernel smoothing or log-normal density fitting. Statistically significant metabolic variations are evaluated using the Benjamini-Yekutieli correction and processed for data sets of various sizes. Optimal sample size determination is achieved in a context of biomarker discovery (at least one statistically significant variation) or metabolic exploration (a maximum of statistically significant variations). DSD toolbox is encoded in MATLAB R2008A (Mathworks, Natick, MA) for Kernel and log-normal estimates, and in GNU Octave for log-normal estimates (Kernel density estimates are not robust enough in GNU octave). It is available at http://www.prabi.fr/redmine/projects/dsd/repository, with a tutorial at http://www.prabi.fr/redmine/projects/dsd/wiki. © The Author 2015. Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

  11. Practice guidelines for the diagnosis and management of microcytic anemias due to genetic disorders of iron metabolism or heme synthesis.

    Science.gov (United States)

    Donker, Albertine E; Raymakers, Reinier A P; Vlasveld, L Thom; van Barneveld, Teus; Terink, Rieneke; Dors, Natasja; Brons, Paul P T; Knoers, Nine V A M; Swinkels, Dorine W

    2014-06-19

    During recent years, our understanding of the pathogenesis of inherited microcytic anemias has gained from the identification of several genes and proteins involved in systemic and cellular iron metabolism and heme syntheses. Numerous case reports illustrate that the implementation of these novel molecular discoveries in clinical practice has increased our understanding of the presentation, diagnosis, and management of these diseases. Integration of these insights into daily clinical practice will reduce delays in establishing a proper diagnosis, invasive and/or costly diagnostic tests, and unnecessary or even detrimental treatments. To assist the clinician, we developed evidence-based multidisciplinary guidelines on the management of rare microcytic anemias due to genetic disorders of iron metabolism and heme synthesis. These genetic disorders may present at all ages, and therefore these guidelines are relevant for pediatricians as well as clinicians who treat adults. This article summarizes these clinical practice guidelines and includes background on pathogenesis, conclusions, and recommendations and a diagnostic flowchart to facilitate using these guidelines in the clinical setting. © 2014 by The American Society of Hematology.

  12. Study by Moessbauer spectroscopy of the iron-dextran (Imferon)

    International Nuclear Information System (INIS)

    Araujo, S.I. de; Danon, J.

    1985-01-01

    The iron-dextran complexes (imferon) are very important in the anemia treatment resulting of the iron insufficiency. Recent studies by electron diffraction denoted that the imferon is structurally different of the ferritin, one protein which constitute the iron reserve substance in the organisms. However, the obtained data in the imferon by Moessbauer spectroscopy, in different temperature ranges (room, liquid nitrogen and liquid He), show a great resemblance between this compound and the ferritin. A Fe 3+ distorted octahedrical coordenation is observed in both compounds, agreeing with measurements done in ferritin by EXAFS. In spite of the concordant results, persist, nevertheless, some discrepancies. The ferritin seems to be a rather more ionic than the imferon, possibly due to the rather higher interatomic distance in the former compound. In these measurements, a field of 484,6 + - 5 KOe is found for the imferon which, compared with the field of 493 + - 10 KOe for ferritin, confirms to be the ferritin more ionic than the imferon. It is, however, a litle difference, when it is compared to the existent between the iron binary oxides β FeOOH and γFeOOH. (L.C.) [pt

  13. Nitric oxide induces hypoxia ischemic injury in the neonatal brain via the disruption of neuronal iron metabolism.

    Science.gov (United States)

    Lu, Qing; Harris, Valerie A; Rafikov, Ruslan; Sun, Xutong; Kumar, Sanjiv; Black, Stephen M

    2015-12-01

    We have recently shown that increased hydrogen peroxide (H2O2) generation is involved in hypoxia-ischemia (HI)-mediated neonatal brain injury. H2O2 can react with free iron to form the hydroxyl radical, through Fenton Chemistry. Thus, the objective of this study was to determine if there was a role for the hydroxyl radical in neonatal HI brain injury and to elucidate the underlying mechanisms. Our data demonstrate that HI increases the deposition of free iron and hydroxyl radical formation, in both P7 hippocampal slice cultures exposed to oxygen-glucose deprivation (OGD), and the neonatal rat exposed to HI. Both these processes were found to be nitric oxide (NO) dependent. Further analysis demonstrated that the NO-dependent increase in iron deposition was mediated through increased transferrin receptor expression and a decrease in ferritin expression. This was correlated with a reduction in aconitase activity. Both NO inhibition and iron scavenging, using deferoxamine administration, reduced hydroxyl radical levels and neuronal cell death. In conclusion, our results suggest that increased NO generation leads to neuronal cell death during neonatal HI, at least in part, by altering iron homeostasis and hydroxyl radical generation. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  14. Oral administration of iron-saturated bovine lactoferrin-loaded ceramic nanocapsules for breast cancer therapy and influence on iron and calcium metabolism.

    Science.gov (United States)

    Mahidhara, Ganesh; Kanwar, Rupinder K; Roy, Kislay; Kanwar, Jagat R

    2015-01-01

    We determined the anticancer efficacy and internalization mechanism of our polymeric-ceramic nanoparticle system (calcium phosphate nanocores, enclosed in biodegradable polymers chitosan and alginate nanocapsules/nanocarriers [ACSC NCs]) loaded with iron-saturated bovine lactoferrin (Fe-bLf) in a breast cancer xenograft model. ACSC-Fe-bLf NCs with an overall size of 322±27.2 nm were synthesized. In vitro internalization and anticancer efficacy were evaluated in the MDA-MB-231 cells using multicellular tumor spheroids, CyQUANT and MTT assays. These NCs were orally delivered in a breast cancer xenograft mice model, and their internalization, cytotoxicity, biodistribution, and anticancer efficacy were evaluated. Chitosan-coated calcium phosphate Fe-bLf NCs effectively (59%, P≤0.005) internalized in a 1-hour period using clathrin-mediated endocytosis (P≤0.05) and energy-mediated pathways (P≤0.05) for internalization; 3.3 mg/mL of ACSC-Fe-bLf NCs completely disintegrated (~130-fold reduction, P≤0.0005) the tumor spheroids in 72 hours and 96 hours. The IC50 values determined for ACSC-Fe-bLf NCs were 1.69 mg/mL at 10 hours and 1.62 mg/mL after 20 hours. We found that Fe-bLf-NCs effectively (P≤0.05) decreased the tumor size (4.8-fold) compared to the void NCs diet and prevented tumor recurrence when compared to intraperitoneal injection of Taxol and Doxorubicin. Receptor gene expression and micro-RNA analysis confirmed upregulation of low-density lipoprotein receptor and transferrin receptor (liver, intestine, and brain). Several micro-RNAs responsible for iron metabolism upregulated with NCs were identified. Taken together, orally delivered Fe-bLf NCs offer enhanced antitumor activity in breast cancer by internalizing via low-density lipoprotein receptor and transferrin receptor and regulating the micro-RNA expression. These NCs also restored the body iron and calcium levels and increased the hematologic counts.

  15. Oral administration of iron-saturated bovine lactoferrin–loaded ceramic nanocapsules for breast cancer therapy and influence on iron and calcium metabolism

    Directory of Open Access Journals (Sweden)

    Mahidhara G

    2015-06-01

    Full Text Available Ganesh Mahidhara, Rupinder K Kanwar, Kislay Roy, Jagat R Kanwar Nanomedicine-Laboratory of Immunology and Molecular Biomedical Research, School of Medicine, Molecular and Medical Research Strategic Research Centre, Faculty of Health, Deakin University, Waurn Ponds, VIC, Australia Abstract: We determined the anticancer efficacy and internalization mechanism of our polymeric–ceramic nanoparticle system (calcium phosphate nanocores, enclosed in biodegradable polymers chitosan and alginate nanocapsules/nanocarriers [ACSC NCs] loaded with iron-saturated bovine lactoferrin (Fe-bLf in a breast cancer xenograft model. ACSC-Fe-bLf NCs with an overall size of 322±27.2 nm were synthesized. In vitro internalization and anticancer efficacy were evaluated in the MDA-MB-231 cells using multicellular tumor spheroids, CyQUANT and MTT assays. These NCs were orally delivered in a breast cancer xenograft mice model, and their internalization, cytotoxicity, biodistribution, and anticancer efficacy were evaluated. Chitosan-coated calcium phosphate Fe-bLf NCs effectively (59%, P≤0.005 internalized in a 1-hour period using clathrin-mediated endocytosis (P≤0.05 and energy-mediated pathways (P≤0.05 for internalization; 3.3 mg/mL of ACSC-Fe-bLf NCs completely disintegrated (~130-fold reduction, P≤0.0005 the tumor spheroids in 72 hours and 96 hours. The IC50 values determined for ACSC-Fe-bLf NCs were 1.69 mg/mL at 10 hours and 1.62 mg/mL after 20 hours. We found that Fe-bLf-NCs effectively (P≤0.05 decreased the tumor size (4.8-fold compared to the void NCs diet and prevented tumor recurrence when compared to intraperitoneal injection of Taxol and Doxorubicin. Receptor gene expression and micro-RNA analysis confirmed upregulation of low-density lipoprotein receptor and transferrin receptor (liver, intestine, and brain. Several micro-RNAs responsible for iron metabolism upregulated with NCs were identified. Taken together, orally delivered Fe-bLf NCs

  16. IronMaking Process Alternatives Screening Study

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2000-10-01

    This study by Lockwood Greene evaluates a number ironmaking processes. The appendices provide greater detail and further exploration of the ironmaking processes, including components, relative costs, and comparisons.

  17. Effects of iron limitation on photosynthesis and carbohydrate metabolism in the Antarctic diatom Chaetoceros brevis (Bacillariophyceae)

    NARCIS (Netherlands)

    van Oijen, T; van Leeuwe, MA; Gieskes, WWC; de Baar, HJW

    Iron, one of the structural elements of organic components that play an essential role in photosynthesis and nitrogen assimilation of plants, is available at extremely low concentrations in large parts of the Southern Ocean's surface waters. We tested the hypothesis that photosynthesis is the

  18. Microbial Metabolism and Inhibition Studies of Phenobarbital ...

    African Journals Online (AJOL)

    Purpose: Screening scale studies were performed with eight cultures for their ability to metabolize phenobarbital, an antiepileptic, sedative, hypnotic and substrate for CYP 2C9 and 2C19. Methods: The transformation of phenobarbital was confirmed and characterized by fermentation techniques, high performance liquid ...

  19. Microbial Metabolism and Inhibition Studies of Phenobarbital

    African Journals Online (AJOL)

    Erah

    techniques, high performance liquid chromatography (HPLC), mass spectrometry (MS) ... Keywords: Microbial metabolism, Phenobarbital, Inhibition studies, Rhizopus stolonifer, CYP 2C9, .... 24 h of incubation 0.5 ml of drug solution was ... mode, positive: spray voltage, 3.5 KV: ... Rhizopus stolonifer showed an extra peak at.

  20. Adsorption studies of iron(III)

    Indian Academy of Sciences (India)

    Adsorption of ferric ions by chitin was studied by the batch equilibration method. The influence of particle size and dosage of the adsorbant, contact time, initial concentration of the adsorbate and temperature were experimentally verified. The effect of anions like chloride, nitrate and sulphate and also of cations like zinc, ...

  1. Iron-57 and iridium-193 Moessbauer spectroscopic studies of supported iron-iridium catalysts

    International Nuclear Information System (INIS)

    Berry, F.J.; Jobson, S.

    1988-01-01

    57 Fe and 193 Ir Moessbauer spectroscopy shows that silica- and alumina-supported iron-iridium catalysts formed by calcination in air contain mixtures of small particle iron(III) oxide and iridium(IV) oxide. The iridium dioxide in both supported catalysts is reduced in hydrogen to metallic iridium. The α-Fe 2 O 3 in the silica supported materials is predominantly reduced in hydrogen to an iron-iridium alloy whilst in the alumina-supported catalyst the iron is stabilised by treatment in hydrogen as iron(II). Treatment of a hydrogen-reduced silica-supported iron catalyst in hydrogen and carbon monoxide is accompanied by the formation of iron carbides. Carbide formation is not observed when the iron-iridium catalysts are treated in similar atmospheres. The results from the bimetallic catalysts are discussed in terms of the hydrogenation of associatively adsorbed carbon monoxide and the selectivity of supported iron-iridium catalysts to methanol formation. (orig.)

  2. Isotope-aided studies of the bioavailability of iron from Myanmar diets

    International Nuclear Information System (INIS)

    Khin Maung Naing; Myo Khin

    1992-01-01

    Iron deficiency is an important nutritional problem in Myanmar. The preliminary studies in this paper are to be used as a feasibility study for an iron fortification programme in Myanmar. This programme is now in the planning stages. This paper contains summaries of information gathered from a dietary survey, isotope-aided studies of the bioavailability of iron from the daily diet, and a work plan for fortifying table salt with iron. 6 refs, 6 tabs

  3. Sintering studies on iron-carbon-copper compacts

    Directory of Open Access Journals (Sweden)

    Perianayagam Philomen-D-Anand Raj

    2016-01-01

    Full Text Available Sintered Iron-Carbon-Copper parts are among the most widely used powder metallurgy product in automobile. In this paper, studies have been carried out to find out the sintering characteristics of iron-carbon-copper compacts when sintered in nitrogen atmosphere. The effects of various processing parameters on the sintering characteristics were studied. The various processing parameters considered were compaction pressure, green density and sintering temperature. The sintering characteristics determined were sintered density, porosity, dimensional change, micro hardness and radial crush strength. The results obtained have been discussed on the basis of micro structural observations. The characteristics of SEM fractography were also used to determine the mechanism of fracture. The fracture energy is strongly dependent on density of the compact.

  4. A study of phosphate absorption by magnesium iron hydroxycarbonate.

    Science.gov (United States)

    Du, Yi; Rees, Nicholas; O'Hare, Dermot

    2009-10-21

    A study of the mechanism of phosphate adsorption by magnesium iron hydroxycarbonate, [Mg(2.25)Fe(0.75)(OH)(6)](CO(3))(0.37).0.65H(2)O over a range of pH has been carried out. The efficiency of the phosphate removal from aqueous solution has been investigated between pH 3-9 and the resulting solid phases have been studied by elemental analysis, XRD, FT-IR, Raman, HRTEM, EDX and solid-state MAS (31)P NMR. The analytical and spectroscopic data suggest that phosphate removal from solution occurs not by anion intercalation of the relevant phosphorous oxyanion (H(2)PO(4)(-) or HPO(4)(2-)) into the LDH but by the precipitation of either an insoluble iron hydrogen phosphate hydrate and/or a magnesium phosphate hydrate.

  5. Isotope aided studies of the bioavailability of iron from common diets from Peru

    International Nuclear Information System (INIS)

    Zavaleta, N.; Diaz, A.; Bedregal, P.; Montoya R, E.

    1993-01-01

    The nutritional iron absorption from a typical peruvian diet was studied by the Eakins and Brown method. the food were breakfast: coffee and bread with butter; lunch: vegetable soup rice with cow tripe stew and lemonade; dinner: vegetable soup and bread. The results show that despite low iron content in the meals, which is not enough to meet daily iron requirements absorption was good in lunch possibly by the action of the promoters ascorbic acid (lemonade) and heme iron (cow tripe). Iron absorption in lunch was good and different from dinner and breakfast. We cannot conclude if the low iron absorption from bread is affected by coffee. (authors). 11 refs., 3 tabs

  6. A preliminary study of iron absorption by whole body counting and correlation with DFO excretion

    International Nuclear Information System (INIS)

    Gupta, M.M.; Bhattacharyya, L.; Gupta, N.K.; Bhola, G.C.; Nagaratnam, A.; Manchanda, R.; Bhargva, M.; Kumar, S.

    1975-01-01

    A preliminary study of iron absorption by oral administration of 59 Fe and whole body counting was carried on a group of 16 women. The cases included 8 patients suffering from iron deficiency anaemia and various infections as well as 8 healthy controls. High iron absorption is associated with iron deficiency, these changes being more marked in iron deficient controls than in those with infection or malignancy. In iron deficient controls results of whole body counting correlate very well with other haematological investigations. (orig.) [de

  7. A Metabolic Study of Huntington's Disease.

    Directory of Open Access Journals (Sweden)

    Rajasree Nambron

    Full Text Available Huntington's disease patients have a number of peripheral manifestations suggestive of metabolic and endocrine abnormalities. We, therefore, investigated a number of metabolic factors in a 24-hour study of Huntington's disease gene carriers (premanifest and moderate stage II/III and controls.Control (n = 15, premanifest (n = 14 and stage II/III (n = 13 participants were studied with blood sampling over a 24-hour period. A battery of clinical tests including neurological rating and function scales were performed. Visceral and subcutaneous adipose distribution was measured using magnetic resonance imaging. We quantified fasting baseline concentrations of glucose, insulin, cholesterol, triglycerides, lipoprotein (a, fatty acids, amino acids, lactate and osteokines. Leptin and ghrelin were quantified in fasting samples and after a standardised meal. We assessed glucose, insulin, growth hormone and cortisol concentrations during a prolonged oral glucose tolerance test.We found no highly significant differences in carbohydrate, protein or lipid metabolism markers between healthy controls, premanifest and stage II/III Huntington's disease subjects. For some markers (osteoprotegerin, tyrosine, lysine, phenylalanine and arginine there is a suggestion (p values between 0.02 and 0.05 that levels are higher in patients with premanifest HD, but not moderate HD. However, given the large number of statistical tests performed interpretation of these findings must be cautious.Contrary to previous studies that showed altered levels of metabolic markers in patients with Huntington's disease, our study did not demonstrate convincing evidence of abnormalities in any of the markers examined. Our analyses were restricted to Huntington's disease patients not taking neuroleptics, anti-depressants or other medication affecting metabolic pathways. Even with the modest sample sizes studied, the lack of highly significant results, despite many being tested, suggests that

  8. Structural properties of iron nitride on Cu(100): An ab-initio molecular dynamics study

    KAUST Repository

    Heryadi, Dodi; Schwingenschlö gl, Udo

    2011-01-01

    Due to their potential applications in magnetic storage devices, iron nitrides have been a subject of numerous experimental and theoretical investigations. Thin films of iron nitride have been successfully grown on different substrates. To study

  9. Optical and magnetization studies on europium based iron pnictides

    Energy Technology Data Exchange (ETDEWEB)

    Zapf, Sina Maria Ute

    2015-07-01

    The investigations carried out in the framework of this thesis mainly concentrate on europium based iron pnictides. These are a peculiar member of the 122 family as they develop at low temperatures (∝20K) an additional magnetic order of the local rare earth moments. Therefore, europium based iron pnictides provide a unique platform to study the interplay of structural, magnetic and electronic effects in high-temperature superconductors. For this challenging purpose, we have employed SQUID magnetometry and Fourier-transform infrared spectroscopy on EuFe{sub 2}(As{sub 1-x}P{sub x}){sub 2} single crystals. By systematic studies of the in- and out-of-plane magnetic properties of a series of single crystals, we derived the complex magnetic phase diagram of europium based iron pnictides, which contains an A-type antiferromagnetic and a re-entrant spin glass phase. Furthermore, we have investigated the magneto-optical properties of EuFe{sub 2}As{sub 2}, revealing a much more complex magnetic detwinning process than expected. These studies demonstrate a remarkable interdependence between magnetic, electronic and structural effects that might be very important to understand the unconventional superconductivity in these fascinating materials.

  10. Acute inhibition of iron bioavailability by zinc: studies in humans.

    Science.gov (United States)

    Olivares, Manuel; Pizarro, Fernando; Ruz, Manuel; de Romaña, Daniel López

    2012-08-01

    Iron (Fe) and zinc (Zn) deficiencies constitute two of the most important nutritional and public health problems affecting developing countries. Combined supplementation or fortification with Zn and Fe are strategies that can be used to improve the Zn and Fe status of a population. However, there is concern about potential negative interactions between these two micronutrients due to a competitive binding to DMT1 and Zip14 transporter. Studies performed in humans have shown an inhibitory effect of Zn on Fe absorption when both minerals are given together as a solution in fasting conditions. We found that at low doses of iron (0.5 mg) the threshold for the inhibition of iron bioavailability was at a Zn:Fe wt/wt ratio ≥5.9:1, whereas at higher doses of Fe (10 mg) this inhibition occurred at 1:1 Zn:Fe wt/wt ratio. This differential response could be explained by the variation in the abundance of both cations as they compete for a limited number of shared transporters at the enterocyte. Conflicting results have been obtained when this interaction was studied in different food matrices. A negative interaction was not observed when Fe and Zn were provided in a composite hamburger meal, premature formula, human milk, or cow milk. A decrease on Fe absorption was observed in only 1 of 3 studies when Fe and Zn were supplied in wheat flour. The possibility of a negative interaction should be considered for supplementation or fortification programs with both microminerals.

  11. Optical and magnetization studies on europium based iron pnictides

    International Nuclear Information System (INIS)

    Zapf, Sina Maria Ute

    2015-01-01

    The investigations carried out in the framework of this thesis mainly concentrate on europium based iron pnictides. These are a peculiar member of the 122 family as they develop at low temperatures (∝20K) an additional magnetic order of the local rare earth moments. Therefore, europium based iron pnictides provide a unique platform to study the interplay of structural, magnetic and electronic effects in high-temperature superconductors. For this challenging purpose, we have employed SQUID magnetometry and Fourier-transform infrared spectroscopy on EuFe 2 (As 1-x P x ) 2 single crystals. By systematic studies of the in- and out-of-plane magnetic properties of a series of single crystals, we derived the complex magnetic phase diagram of europium based iron pnictides, which contains an A-type antiferromagnetic and a re-entrant spin glass phase. Furthermore, we have investigated the magneto-optical properties of EuFe 2 As 2 , revealing a much more complex magnetic detwinning process than expected. These studies demonstrate a remarkable interdependence between magnetic, electronic and structural effects that might be very important to understand the unconventional superconductivity in these fascinating materials.

  12. Tick iron and heme metabolism – New target for an anti-tick intervention

    Czech Academy of Sciences Publication Activity Database

    Hajdušek, Ondřej; Šíma, Radek; Perner, Jan; Loosová, Gabriela; Harcubová, Adéla; Kopáček, Petr

    2016-01-01

    Roč. 7, č. 4 (2016), s. 565-572 ISSN 1877-959X R&D Projects: GA ČR GA13-11043S; GA ČR GP13-27630P; GA ČR GP13-12816P EU Projects: European Commission(XE) 316304 - MODBIOLIN Institutional support: RVO:60077344 Keywords : tick * iron * heme * RNAi * vaccine Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.230, year: 2016

  13. Changes in serum markers of iron metabolism and their clinical significance in patients with nonalcoholic fatty liver disease

    Directory of Open Access Journals (Sweden)

    OU Qiang

    2016-12-01

    Full Text Available ObjectiveTo investigate the changes in the serum markers of iron metabolism and their clinical significance in patients with nonalcoholic fatty liver disease (NAFLD. MethodsA total of 68 NAFLD patients who were admitted to The Eighth People′s Hospital of Shanghai from July 2014 to April 2016 were enrolled as NAFLD group, and 70 healthy persons who underwent physical examination were enrolled as healthy control group. Among the 68 patients in the NAFLD group, 24 had NAFLD alone and 44 were complicated by abnormal alanine aminotransferase (ALT level. The levels of aspartate aminotransferase (AST, ALT, total cholesterol (TC, triglyceride (TG, and serum markers of iron metabolism [serum iron (SI, serum ferritin (SF, and serum hepcidin (HEPC] were measured for all patients, and the correlations between abnormal ALT level and serum markers of iron metabolism were analyzed. The independent samples t-test was used for comparison of continuous data between groups, the chi-square test was used for comparison of categorical data between groups, and the Pearson correlation coefficient was used to investigate the correlation between two variables. ResultsThe NAFLD group had significantly higher body mass index and serum levels of ALT, AST, TC, and TG than the healthy control group (t=9.8, 8.6, 8.5, 9.2, and 2.7, all P<0.05. Compared with the healthy control group, the NAFLD group had significantly higher levels of SI (21.7±7.1 μmol/L vs 187±6.9 μmol/L, t=2.3, P=0.02 and SF (340.2±257.6 μg/L vs 119.1±81.2 μg/L, t=6.7, P<0.01 and a significantly lower level of HEPC (12.2±5.3 μg/L vs 22.2±6.5 μg/L, t=9.9, P<0.01. Compared with those with NAFLD alone, the patients complicated by abnormal ALT level had significantly higher serum levels of ALT (89±58 U/L vs 26±8 U/L, t=7.1, P<0.01, SI (23.4±6.2 μmol/L vs 19.6±7.9 μmol/L, t=2.2, P=0.03, and SF (406.2±290.0 μg/L vs 219.4±112.0 μg/L, t=3.7, P<0.01, as well as a significantly

  14. Pulse radiolysis studies of iron(I) in aqueous solutions

    International Nuclear Information System (INIS)

    Nenadovic, M.T.; Micic, O.I.; Muk, A.A.

    1980-01-01

    The absorption spectrum and decay kinetics of the products of the reactions of iron(II) ions with hydrated electrons and hydrogen atoms have been studied in aqueous solution using pulse-radiolysis techniques. Iron(I) is formed by reaction with hydrated electrons and its absorption spectrum is reported and discussed. The formation of molecular hydrogen by reaction of Fe + with water is suppressed by other solutes present in the solutions. In acidic solutions containing [SO 4 ] 2- , the intermediates formed in the reaction with H atoms decay by a first-order process and produce molecular hydrogen, but the rate of their decay does not depend only on the oxonium ion concentration but also on intermolecular rearrangement in the [FeSO 4 -H] complex. (author)

  15. Non-destructive study of iron gall inks in manuscripts

    Science.gov (United States)

    Duh, Jelena; Krstić, Dragica; Desnica, Vladan; Fazinić, Stjepko

    2018-02-01

    The aim of this research is to establish an effective procedure of iron gall ink characterization using complementary non-destructive methods. By this, it is possible to better understand correlation of chemical composition of the inks and the state of preservation of iron gall ink manuscripts, as well as the effects of conservation treatment performed upon them. This study was undertaken on a bound 16th century manuscript comprised of different types of paper and ink from the National and University Library in Zagreb. Analytical methods used included Particle Induced X-ray Emission (PIXE) and X-ray Fluorescence (XRF). Paper fibers were identified by optical microscopy and the degradation state, as well as ink differentiation, transit metal migrations and detection of stains, with ultraviolet (UV) and infrared (IR) photography. The techniques applied on original writing materials gave important information about paper and ink composition, its preservation state and efficiency of conservation treatment performed upon them.

  16. Studies of coal liquefaction (50). Catalysis of iron compounds

    Energy Technology Data Exchange (ETDEWEB)

    Tamura, Tomoyuki; Ogata, Eisuke; Kamiya, Yoshio

    1956-10-23

    A study is made to determine the catalytic actions and changes in grain size and surface area of various iron compound catalysts used for hydrogenation of phenanthrene. Effects of oxygen-containing compounds on the reaction are also investigated. Reactions of phenanthrene or CLB samples are performed in decalin or 1-methylnaphthalene as solvent. The solid reaction residue, including the catalyst used, is filtered and washed in acetone to provide specimens for SEM, surface area measurement (BET) and XRD. Three of the iron catalysts examined, CGS, FE(CO)/sub 5/ and FeS/sub 2/, are found to be highly effective for both phenanthrene hydrogenation and CLB decomposition, while Fe/sub 3/C does not work effectively for either of them. Fe (zero valene) and Fe/sub 2/O/sub 3/ are found effective for phenanthrene hydrogenation but not for CLB decomposition. (7 tabs)

  17. Isotope aided studies on the bioavailability of iron and zinc from human diets

    International Nuclear Information System (INIS)

    Raghuramulu, N.

    1992-01-01

    Iron deficiency anaemia is a major public health problem in many developing countries including India. Recent multicentric studies indicated that in rural population of India, 60% of preschool children and 40-60 % of women of child bearing age may suffer from anaemia. Studies by Sood et al indicated that iron stores are generally lower in the population as compared to populations in other countries. It is therefore possible that prelatent iron deficiency may be even higher who look otherwise healthy and adequately nourished. Iron absorption from habitual diets of Indians has been determined in the past by the chemical balance methods. Iron absorption determined by this method may be a gross over estimate. A more reliable estimate of iron absorption from composite meals can be obtained by the radio isotopic methods in which foods are extrinsically or intrinsically tagged with radio iron ( 55 Fe or 59 Fe). Using these methods iron absorption from a few habitual diets was studied. 15 refs

  18. Comparative study of biogenic and abiotic iron-containing materials

    Energy Technology Data Exchange (ETDEWEB)

    Cherkezova-Zheleva, Z., E-mail: zzhel@ic.bas.bg; Shopska, M., E-mail: shopska@ic.bas.bg; Paneva, D. [Bulgarian Academy of Sciences, Institute of Catalysis (Bulgaria); Kovacheva, D. [Bulgarian Academy of Sciences, Institute of General and Inorganic Chemistry (Bulgaria); Kadinov, G.; Mitov, I. [Bulgarian Academy of Sciences, Institute of Catalysis (Bulgaria)

    2016-12-15

    Series of iron-based biogenic materials prepared by cultivation of Leptothrix group of bacteria in different feeding media (Sphaerotilus-Leptothrix group of bacteria isolation medium, Adler, Lieske and silicon-iron-glucose-peptone) were studied. Control samples were obtained in the same conditions and procedures but the nutrition media were not infected with bacteria, i.e. they were sterile. Room and low temperature Mössbauer spectroscopy, powder X-ray diffraction (XRD), and infrared spectroscopy (IRS) were used to reveal the composition and physicochemical properties of biomass and respective control samples. Comparative analysis showed differences in their composition and dispersity of present phases. Sample composition included different ratio of nanodimensional iron oxyhydroxide and oxide phases. Relaxation phenomena such as superparamagnetism or collective magnetic excitation behaviour were registered for some of them. The experimental data showed that the biogenic materials were enriched in oxyhydroxides of high dispersion. Catalytic behaviour of a selected biomass and abiotic material were studied in the reaction of CO oxidation. In situ diffuse-reflectance (DR) IRS was used to monitor the phase transformations in the biomass and CO conversion.

  19. Metabolic cartography: experimental quantification of metabolic fluxes from isotopic labelling studies.

    Science.gov (United States)

    O'Grady, John; Schwender, Jörg; Shachar-Hill, Yair; Morgan, John A

    2012-03-01

    For the past decade, flux maps have provided researchers with an in-depth perspective on plant metabolism. As a rapidly developing field, significant headway has been made recently in computation, experimentation, and overall understanding of metabolic flux analysis. These advances are particularly applicable to the study of plant metabolism. New dynamic computational methods such as non-stationary metabolic flux analysis are finding their place in the toolbox of metabolic engineering, allowing more organisms to be studied and decreasing the time necessary for experimentation, thereby opening new avenues by which to explore the vast diversity of plant metabolism. Also, improved methods of metabolite detection and measurement have been developed, enabling increasingly greater resolution of flux measurements and the analysis of a greater number of the multitude of plant metabolic pathways. Methods to deconvolute organelle-specific metabolism are employed with increasing effectiveness, elucidating the compartmental specificity inherent in plant metabolism. Advances in metabolite measurements have also enabled new types of experiments, such as the calculation of metabolic fluxes based on (13)CO(2) dynamic labelling data, and will continue to direct plant metabolic engineering. Newly calculated metabolic flux maps reveal surprising and useful information about plant metabolism, guiding future genetic engineering of crops to higher yields. Due to the significant level of complexity in plants, these methods in combination with other systems biology measurements are necessary to guide plant metabolic engineering in the future.

  20. In vitro studies on interactions of iron salts and complexes with food-stuffs and medicaments.

    Science.gov (United States)

    Geisser, P

    1990-07-01

    It has been shown in the present study that food components such as phytic acid, oxalic acid, tannin, sodium alginate, choline and choline salts, vitamins A, D3 and E, soy oil and soy flour, do not undergo any interactions with iron(III)-hydroxide polymaltose complex (Ferrum Hausmann). Phytic acid, oxalic acid, tannin and sodium alginate, however, react with iron(II) or iron(III)-salts at pH values of 3.0, 5.5 and 8.0, giving rise to iron complexes. Trimethylamine-N-oxide, which is present in fish meal, reacts with iron(II)-sulphate to produce iron(III) reaction products; it does not react with iron(III)-hydroxide polymaltose complex. Special soybean flours show no irreversible adsorption or precipitation with iron(III)-hydroxyide polymaltose complex over the pH range 3.0-8.0, in contrast to iron(II)-sulphate. Antacids containing aluminium hydroxide, talc, ion exchange resins or other unabsorbable, insoluble components absorb iron(III)-hydroxide polymaltose complex in the pH range 3.0-8.0 in a reversible manner, while the strong adsorption or precipitation observed with iron(II)-sulphate at pH 8.0 is irreversible. No interaction was observed between the steroid hormones studied and iron(II)-sulphate or iron(III)-hydroxide polymaltose complex. On the basis of the measured compatibilities, iron(III)-hydroxide polymaltose complex can be administered orally simultaneously with many other drugs, without prejudicing the absorption of iron or of the other drug as is often seen with iron(II) and iron(III) salts.

  1. Contribution of macrophages in the contrast loss in iron oxide-based MRI cancer cell tracking studies

    Science.gov (United States)

    Danhier, Pierre; Deumer, Gladys; Joudiou, Nicolas; Bouzin, Caroline; Levêque, Philippe; Haufroid, Vincent; Jordan, Bénédicte F.; Feron, Olivier; Sonveaux, Pierre; Gallez, Bernard

    2017-01-01

    Magnetic resonance imaging (MRI) cell tracking of cancer cells labeled with superparamagnetic iron oxides (SPIO) allows visualizing metastatic cells in preclinical models. However, previous works showed that the signal void induced by SPIO on T2(*)-weighted images decreased over time. Here, we aim at characterizing the fate of iron oxide nanoparticles used in cell tracking studies and the role of macrophages in SPIO metabolism. In vivo MRI cell tracking of SPIO positive 4T1 breast cancer cells revealed a quick loss of T2* contrast after injection. We next took advantage of electron paramagnetic resonance (EPR) spectroscopy and inductively coupled plasma mass spectroscopy (ICP-MS) for characterizing the evolution of superparamagnetic and non-superparamagnetic iron pools in 4T1 breast cancer cells and J774 macrophages after SPIO labeling. These in vitro experiments and histology studies performed on 4T1 tumors highlighted the quick degradation of iron oxides by macrophages in SPIO-based cell tracking experiments. In conclusion, the release of SPIO by dying cancer cells and the subsequent uptake of iron oxides by tumor macrophages are limiting factors in MRI cell tracking experiments that plead for the use of (MR) reporter-gene based imaging methods for the long-term tracking of metastatic cells. PMID:28467814

  2. Are Lotus species good models for studying iron accumulation in common beans?

    DEFF Research Database (Denmark)

    Orlowska, Elzbieta; Laszcyca, Katarzyna Malgorzata; Urbanski, Dorian Fabian

    show that the iron distribution in L. filicaulis seeds is similar to that  in common beans, while the seeds of L. japonicus show a different pattern of iron accumulation. RILs from a cross between these two species are being studied in order to find genes that are important for seed iron distribution...

  3. A contribution to the study of the structure, reactivity and bioinorganic chemistry of iron

    International Nuclear Information System (INIS)

    Toma, H.E.

    1984-01-01

    The research work on inorganic and biological chemistry of iron developed at the University of Sao Paulo (SP, Brazil) is reviewed. Considerations are made about: π interactions, electronic structure and spectroscopy of cyanoferrates; solvation studies and kinetics of substitution reactions involving iron complexes; reactivity of coordinating ligands and iron interactions with biomolecules. (C.L.B.) [pt

  4. X-ray emission spectroscopy study of iron silicate catalyst FeZSM-5

    International Nuclear Information System (INIS)

    Csencsits, R.; Lyman, C.E.; Gronsky, R.

    1988-03-01

    Iron silicate analogs of the zeolite ZMS-5 may be directly synthesized from iron silicate gels in a manner which differs slightly from the alumino-silicate ZSM-5. The resultant white, crystalline iron silicate is referred to as FeZSM-5 in the as-synthesized form. Thermal treatment removes the organic crystal-directing agent and moves some of the framework iron into non-framework sites producing the calcined form of the molecular sieve FeZSM-5. Homogeneity in the distribution of catalytic iron throughout the particles is desired in an optimal catalyst. Distribution of the iron throughout the framework in the as-synthesized forms would affect the final distribution of catalytic iron in the calcined and steamed forms; thus, the iron distribution throughout the as-synthesized and calcined forms of FeZSM-5 were studied using the high spatial resolution on the analytical electron microscope. 7 refs., 3 figs

  5. Growth of Rhodococcus sp. strain BCP1 on gaseous n-alkanes: new metabolic insights and transcriptional analysis of two soluble di-iron monooxygenase genes

    Directory of Open Access Journals (Sweden)

    Martina eCappelletti

    2015-05-01

    Full Text Available Rhodococcus sp. strain BCP1 was initially isolated for its ability to grow on gaseous n-alkanes, which act as inducers for the co-metabolic degradation of low-chlorinated compounds. Here, both molecular and metabolic features of BCP1 cells grown on gaseous and short-chain n-alkanes (up to n-heptane were examined in detail. We show that propane metabolism generated terminal and sub-terminal oxidation products such as 1- and 2-propanol, whereas 1-butanol was the only terminal oxidation product detected from butane metabolism. Two gene clusters, prmABCD and smoABCD – coding for soluble di-iron monooxgenases (SDIMOs involved in gaseous n-alkanes oxidation – were detected in the BCP1 genome. By means of reverse transcriptase-quantitative PCR (RT-qPCR analysis, a set of substrates inducing the expression of the sdimo genes in BCP1 were assessed as well as their transcriptional repression in the presence of sugars, organic acids or during the cell growth on rich medium (Luria Bertani broth. The transcriptional start sites of both the sdimo gene clusters were identified by means of primer extension experiments. Finally, proteomic studies revealed changes in the protein pattern induced by growth on gaseous- (n-butane and/or liquid (n-hexane short-chain n-alkanes as compared to growth on succinate. Among the differently expressed protein spots, two chaperonins and an isocytrate lyase were identified along with oxidoreductases involved in oxidation reactions downstream of the initial monooxygenase reaction step.

  6. Growth of Rhodococcus sp. strain BCP1 on gaseous n-alkanes: new metabolic insights and transcriptional analysis of two soluble di-iron monooxygenase genes

    Science.gov (United States)

    Cappelletti, Martina; Presentato, Alessandro; Milazzo, Giorgio; Turner, Raymond J.; Fedi, Stefano; Frascari, Dario; Zannoni, Davide

    2015-01-01

    Rhodococcus sp. strain BCP1 was initially isolated for its ability to grow on gaseous n-alkanes, which act as inducers for the co-metabolic degradation of low-chlorinated compounds. Here, both molecular and metabolic features of BCP1 cells grown on gaseous and short-chain n-alkanes (up to n-heptane) were examined in detail. We show that propane metabolism generated terminal and sub-terminal oxidation products such as 1- and 2-propanol, whereas 1-butanol was the only terminal oxidation product detected from n-butane metabolism. Two gene clusters, prmABCD and smoABCD—coding for Soluble Di-Iron Monooxgenases (SDIMOs) involved in gaseous n-alkanes oxidation—were detected in the BCP1 genome. By means of Reverse Transcriptase-quantitative PCR (RT-qPCR) analysis, a set of substrates inducing the expression of the sdimo genes in BCP1 were assessed as well as their transcriptional repression in the presence of sugars, organic acids, or during the cell growth on rich medium (Luria–Bertani broth). The transcriptional start sites of both the sdimo gene clusters were identified by means of primer extension experiments. Finally, proteomic studies revealed changes in the protein pattern induced by growth on gaseous- (n-butane) and/or liquid (n-hexane) short-chain n-alkanes as compared to growth on succinate. Among the differently expressed protein spots, two chaperonins and an isocytrate lyase were identified along with oxidoreductases involved in oxidation reactions downstream of the initial monooxygenase reaction step. PMID:26029173

  7. Moessbauer and EPR studies on iron-dihydroxybenzoic acid and iron-itoic acid chelate complexes

    International Nuclear Information System (INIS)

    Bagyinka, Cs.; Horvath, L.I.; Keszthelyi, L.

    1984-01-01

    Low molecular weight iron-dihydroxybenzoic acid and iron-itoic acid complexes were investigated by Moessbauer and EPR spectroscopy. In strong acidic medium the iron is chelated in high spin ferrous form. By varying the pH of the medium a (S=2)Fesup(2+)→(S=5/2)Fesup(3+) transition was found with a midpoint pH value of 4. From the g'-tensor anisotropy it is concluded that the metal atom is coordinated by six oxygen atoms in rhombically distorted octahedral configuration. The biological significance of these structural data is briefly discussed. (author)

  8. Effects of calorie restriction plus fish oil supplementation on abnormal metabolic characteristics and the iron status of middle-aged obese women.

    Science.gov (United States)

    Utami, Fasty Arum; Lee, Hsiu-Chuan; Su, Chien-Tien; Guo, Yu-Ru; Tung, Yu-Tang; Huang, Shih-Yi

    2018-02-21

    The increasing prevalence of obesity and sedentary lifestyles has led to a higher incidence of metabolic syndrome (MetS) worldwide as well as in Taiwan. Middle-aged women are at a greater risk of MetS, type 2 diabetes, and cardiovascular disease than men because they have more subcutaneous fat and larger waist circumferences compared with men with equal visceral fat levels. In this study, we investigated the effects of calorie restriction (CR) and fish oil supplementation (CRF) on middle-aged Taiwanese women with MetS. An open-label, parallel-arm, controlled trial was conducted for 12 weeks. A total of 75 eligible participants were randomly assigned to the CR or CRF group. Both the dietary intervention groups were further divided into two age groups: ≤45 and >45 years. Changes in MetS severity, inflammatory status, iron status, and red blood cell fatty acid profile were evaluated. A total of 71 participants completed the trial. Both dietary interventions significantly ameliorated MetS and improved the participants' inflammatory status. CR significantly increased the total iron-binding capacity (TIBC) whereas CRF increased hepcidin levels in women aged >45 years. Furthermore, CRF significantly increased the n-6/n-3 and arachidonic acid/docosahexaenoic acid ratios. Both interventions improved the anthropometric and MetS characteristics, including body weight, blood glucose and triglyceride levels, and the score of the homeostasis model assessment of insulin resistance and quantitative insulin sensitivity check index. In conclusion, the 12-week dietary interventions improved the abnormal metabolic status of middle-aged obese women. CRF was demonstrated to be more effective in ameliorating postprandial glucose level and TIBC in women aged >45 years than in those aged ≤45 years.

  9. NMR-based metabonomic analyses of the effects of ultrasmall superparamagnetic particles of iron oxide (USPIO) on macrophage metabolism

    Science.gov (United States)

    Feng, Jianghua; Zhao, Jing; Hao, Fuhua; Chen, Chang; Bhakoo, Kishore; Tang, Huiru

    2011-05-01

    The metabonomic changes in murine RAW264.7 macrophage-like cell line induced by ultrasmall superparamagnetic particles of iron oxides (USPIO) have been investigated, by analyzing both the cells and culture media, using high-resolution NMR in conjunction with multivariate statistical methods. Upon treatment with USPIO, macrophage cells showed a significant decrease in the levels of triglycerides, essential amino acids such as valine, isoleucine, and choline metabolites together with an increase of glycerophospholipids, tyrosine, phenylalanine, lysine, glycine, and glutamate. Such cellular responses to USPIO were also detectable in compositional changes of cell media, showing an obvious depletion of the primary nutrition molecules, such as glucose and amino acids and the production of end-products of glycolysis, such as pyruvate, acetate, and lactate and intermediates of TCA cycle such as succinate and citrate. At 48 h treatment, there was a differential response to incubation with USPIO in both cell metabonome and medium components, indicating that USPIO are phagocytosed and released by macrophages. Furthermore, information on cell membrane modification can be derived from the changes in choline-like metabolites. These results not only suggest that NMR-based metabonomic methods have sufficient sensitivity to identify the metabolic consequences of murine RAW264.7 macrophage-like cell line response to USPIO in vitro, but also provide useful information on the effects of USPIO on cellular metabolism.

  10. NMR-based metabonomic analyses of the effects of ultrasmall superparamagnetic particles of iron oxide (USPIO) on macrophage metabolism

    International Nuclear Information System (INIS)

    Feng Jianghua; Zhao Jing; Hao Fuhua; Chen Chang; Bhakoo, Kishore; Tang, Huiru

    2011-01-01

    The metabonomic changes in murine RAW264.7 macrophage-like cell line induced by ultrasmall superparamagnetic particles of iron oxides (USPIO) have been investigated, by analyzing both the cells and culture media, using high-resolution NMR in conjunction with multivariate statistical methods. Upon treatment with USPIO, macrophage cells showed a significant decrease in the levels of triglycerides, essential amino acids such as valine, isoleucine, and choline metabolites together with an increase of glycerophospholipids, tyrosine, phenylalanine, lysine, glycine, and glutamate. Such cellular responses to USPIO were also detectable in compositional changes of cell media, showing an obvious depletion of the primary nutrition molecules, such as glucose and amino acids and the production of end-products of glycolysis, such as pyruvate, acetate, and lactate and intermediates of TCA cycle such as succinate and citrate. At 48 h treatment, there was a differential response to incubation with USPIO in both cell metabonome and medium components, indicating that USPIO are phagocytosed and released by macrophages. Furthermore, information on cell membrane modification can be derived from the changes in choline-like metabolites. These results not only suggest that NMR-based metabonomic methods have sufficient sensitivity to identify the metabolic consequences of murine RAW264.7 macrophage-like cell line response to USPIO in vitro, but also provide useful information on the effects of USPIO on cellular metabolism.

  11. Equilibrium and stability studies for an iron-core tokamak with a poloidal divertor

    International Nuclear Information System (INIS)

    Solano, E.R.; Neilson, G.H.; Lao, L.L.

    1989-01-01

    A study of plasma equilibrium and stability in a tokamak with an unsaturated iron core is presented. A spool model is developed for the iron. Both, a simplified force balance code and a Grad-Shafranov solver are used to study the plasma equilibrium. It is observed that the iron can strongly modify the conditions for equilibrium and stability, and in some cases an infinite cylinder model for the iron core is not adequate. New criteria for plasma position stability in the presence of an iron core are introduced. 17 refs., 4 figs., 3 tabs

  12. Use of a standard meal to study iron absorption in humans

    International Nuclear Information System (INIS)

    Reddy, M.B.; Cook, J.D.

    1994-01-01

    Iron absorption varies widely between subjects and groups of subjects because of differences in iron status which markedly influence iron assimilation from the gastrointestinal tract. A small dose of isotopically labelled inorganic iron termed the reference dose (3 mg iron as FeSO 4 ) has been used extensively during the past two decades to standardize food iron absorption in human subjects and thereby eliminate the effect of differences in iron status. Recent studies from this laboratory have shown that because of the high variability of absorption from the reference dose, nonheme iron absorption from a standardized meal provides a more reliable means of standardizing absorption from regional diets. We therefore performed initial studies with a rice based meal but we found a relatively high variation in absorption from 2.0 to 4.7% that presumably reflects differences in the phytate content of rice fours. We then undertook the evaluation of meals prepared with farina, a wheat product that is available in most regions of the world. In six different studies from a farina based meal, iron absorption ranged from 3.4 to 6.5%. Nonheme iron absorption from the farina meal when evaluated in separate laboratories extensively engaged in human studies of iron absorption, ranged from 5.1 to 10.8% but when related to the FeSO 4 dose, a more consistent ratio between 0.21 to 0.26 was observed with the exception of one laboratory where a very low absorption of 1.1.% was observed. Percentage absorption from the farina based meal decreased when the iron content of the meal was increased and showed the expected facilitation of absorption when increasing amounts of ascorbic acid were added. By reducing variability and measuring iron absorption from food rather than inorganic iron, we believe that the use of this standard meal will facilitate comparison of iron absorption data obtained in laboratories throughout the world. 4 refs, 2 tabs

  13. Iron Bioavailability Studies of the First Generation of Iron-Biofortified Beans Released in Rwanda.

    Science.gov (United States)

    Glahn, Raymond; Tako, Elad; Hart, Jonathan; Haas, Jere; Lung'aho, Mercy; Beebe, Steve

    2017-07-21

    This paper represents a series of in vitro iron (Fe) bioavailability experiments, Fe content analysis and polyphenolic profile of the first generation of Fe biofortified beans ( Phaseolus vulgaris ) selected for human trials in Rwanda and released to farmers of that region. The objective of the present study was to demonstrate how the Caco-2 cell bioassay for Fe bioavailability can be utilized to assess the nutritional quality of Fe in such varieties and how they may interact with diets and meal plans of experimental studies. Furthermore, experiments were also conducted to directly compare this in vitro approach with specific human absorption studies of these Fe biofortified beans. The results show that other foods consumed with beans, such as rice, can negatively affect Fe bioavailability whereas potato may enhance the Fe absorption when consumed with beans. The results also suggest that the extrinsic labelling approach to measuring human Fe absorption can be flawed and thus provide misleading information. Overall, the results provide evidence that the Caco-2 cell bioassay represents an effective approach to evaluate the nutritional quality of Fe-biofortified beans, both separate from and within a targeted diet or meal plan.

  14. Study on wear resistance of vanadium alloying compacted/vermicular graphite cast iron

    International Nuclear Information System (INIS)

    Park, Yoon Woo

    1987-01-01

    Wear resistance of the Compacted/Vermicular graphite cast irons was studied by changing the vanadium content in the cast irons. The results obtained in this work are summarized as follows. 1. When the same amount of vanadium was added to the flake graphite cast iron, spheroidal graphitecast iron and Compacted/Vermicular graphite cast iron, spheroidal graphite cast iron and Compacted/Vermicular graphite cast iron wear resistance decreased in following sequence, that is, flake graphite cast iron> spheroidal graphite cast iron>Compacted/Vermicular graphite cast iron. 2. Addition of vanadium to the Compacted/Vermicular cast iron leaded to a remarkable increase in hardness because it made the amount of pearlite in matrix increase. 3. Addition of vanadium to the compacted/Vermicular graphite cast iron significantly enhanced wear resistance and the maximum resistance was achieved at about 0.36% vanadium. 4. The maximum amount of wear apppeared at sliding speed of about 1.4m/sec and wear mode was considered to be oxidation abrasion from the observation of wear tracks. (Author)

  15. Nuclear magnetic resonance studies of metabolic regulation

    International Nuclear Information System (INIS)

    Sillerud, L.O.; Han, C.H.; Whaley, T.W.

    1983-01-01

    Nuclear magnetic resonance (NMR) techniques for the detection of the metabolic transformations of biological compounds labeled with stable isotopes, particularly carbon-13 have been explored. We have studied adipose tissue in the intact rat, the exteriorized epididymal fat pad, and the isolated adipocyte. Triacylglycerol metabolism in adipose tissue is regulated by lipogenic factors (insulin, corticosterone, thyroxine, and growth hormone) and lipolytic factors (glucagon and catecholamines). The synthesis of triglyceride from 5.5 mM glucose was stimulated by about 4-fold by 10 nM insulin. Triglyceride synthesis from glucose in the presence of insulin occurred at a rate of 330 nmol/hr/10 6 cells. Since the NMR signals from free and esterified fatty acids and glycerol are distinct, we could directly measure the rate of hormone-stimulated lipolysis. Epinephrine (10 μM) gave a lipolytic rate of 0.30 μmol/hr/10 6 cells as monitored by free-glycerol appearance in the medium. 13 C NMR provides a superior method for the measurement of triglyceride metabolism since it directly measures the changes in the substrates and products in situ

  16. Metabolic Desynchronization in Critical Conditions: Experimental Study

    Directory of Open Access Journals (Sweden)

    G. V. Livanov

    2006-01-01

    Full Text Available Objective. To conduct an experimental study of the impact of the time of administration of succinic acid preparations on central nervous system (CNS function and gas exchange while simulating metabolic therapy for severe poisoning by ethyl alcohol. The study was performed on 74 male albino rats weighing 140—180 g. Acute severe and very severe intoxication was simulated, by intraabdominally administering 30% ethanol to the rats. Cytoflavin was used to simulate experimental therapy. The rate of gas exchange was estimated by the oxygen uptake determined by the closed chamber method in a Regnault apparatus (Germany. Spontaneous bioelectrical activity was recorded in the frontooccipital lead by the routine procedure. External pain stimulation and rhythmical photostimulation were employed to evaluate cerebral responsiveness. Heterodirectional EEG changes in the «early» and «late» administration of succinate were not followed by the similar alterations of gas exchange: oxygen consumption in both the «early» and «late» administration of succinate remained significantly lower than in the control animals. With the late administration of succinate to the animals with mixed (toxic and hypoxic coma, the so-called discrepancy between the noticeably increased energy production and brutally diminished metabolism occurred. It may be just the pathological mechanism that was the basis for higher mortality in the late succinate administration group. The findings and their analysis make it possible to advance a hypothesis that succinate may cause metabolic desynchronization if activation of metabolic processes takes place under severe tissue respiratory tissue depression. In these cases, there is a severe damage to tissue and chiefly the brain. This manifests itself as EEG epileptiform activity splashes preceding the animals’ death. Therefore, resuscitation aimed at restoring the transport of oxygen and its involvement in tissue energy processes should

  17. Iron metabolism mutant hbd mice have a deletion in Sec15l1, which has homology to a yeast gene for vesicle docking.

    Science.gov (United States)

    White, Robert A; Boydston, Leigh A; Brookshier, Terri R; McNulty, Steven G; Nsumu, Ndona N; Brewer, Brandon P; Blackmore, Krista

    2005-12-01

    Defects in iron absorption and utilization lead to iron deficiency and anemia. While iron transport by transferrin receptor-mediated endocytosis is well understood, it is not completely clear how iron is transported from the endosome to the mitochondria where heme is synthesized. We undertook a positional cloning project to identify the causative mutation for the hemoglobin-deficit (hbd) mouse mutant, which suffers from a microcytic, hypochromic anemia apparently due to defective iron transport in the endocytosis cycle. As shown by previous studies, reticulocyte iron accumulation in homozygous hbd/hbd mice is deficient despite normal binding of transferrin to its receptor and normal transferrin uptake in the cell. We have identified a strong candidate gene for hbd, Sec15l1, a homologue to yeast SEC15, which encodes a key protein in vesicle docking. The hbd mice have an exon deletion in Sec15l1, which is the first known mutation of a SEC gene homologue in mammals.

  18. Nanoscale zero-valent iron/persulfate enhanced upflow anaerobic sludge blanket reactor for dye removal: Insight into microbial metabolism and microbial community

    Science.gov (United States)

    Pan, Fei; Zhong, Xiaohan; Xia, Dongsheng; Yin, Xianze; Li, Fan; Zhao, Dongye; Ji, Haodong; Liu, Wen

    2017-03-01

    This study investigated the efficiency of nanoscale zero-valent iron combined with persulfate (NZVI/PS) for enhanced degradation of brilliant red X-3B in an upflow anaerobic sludge blanket (UASB) reactor, and examined the effects of NZVI/PS on anaerobic microbial communities during the treatment process. The addition of NZVI (0.5 g/L) greatly enhanced the decolourization rate of X-3B from 63.8% to 98.4%. The Biolog EcoPlateTM technique was utilized to examine microbial metabolism in the reactor, and the Illumina MiSeq high-throughput sequencing revealed 22 phyla and 88 genera of the bacteria. The largest genera (Lactococcus) decreased from 33.03% to 7.94%, while the Akkermansia genera increased from 1.69% to 20.23% according to the abundance in the presence of 0.2 g/L NZVI during the biological treatment process. Meanwhile, three strains were isolated from the sludge in the UASB reactors and identified by 16 S rRNA analysis. The distribution of three strains was consistent with the results from the Illumina MiSeq high throughput sequencing. The X-ray photoelectron spectroscopy results indicated that Fe(0) was transformed into Fe(II)/Fe(III) during the treatment process, which are beneficial for the microorganism growth, and thus promoting their metabolic processes and microbial community.

  19. Nanoscale zero-valent iron/persulfate enhanced upflow anaerobic sludge blanket reactor for dye removal: Insight into microbial metabolism and microbial community

    Science.gov (United States)

    Pan, Fei; Zhong, Xiaohan; Xia, Dongsheng; Yin, Xianze; Li, Fan; Zhao, Dongye; Ji, Haodong; Liu, Wen

    2017-01-01

    This study investigated the efficiency of nanoscale zero-valent iron combined with persulfate (NZVI/PS) for enhanced degradation of brilliant red X-3B in an upflow anaerobic sludge blanket (UASB) reactor, and examined the effects of NZVI/PS on anaerobic microbial communities during the treatment process. The addition of NZVI (0.5 g/L) greatly enhanced the decolourization rate of X-3B from 63.8% to 98.4%. The Biolog EcoPlateTM technique was utilized to examine microbial metabolism in the reactor, and the Illumina MiSeq high-throughput sequencing revealed 22 phyla and 88 genera of the bacteria. The largest genera (Lactococcus) decreased from 33.03% to 7.94%, while the Akkermansia genera increased from 1.69% to 20.23% according to the abundance in the presence of 0.2 g/L NZVI during the biological treatment process. Meanwhile, three strains were isolated from the sludge in the UASB reactors and identified by 16 S rRNA analysis. The distribution of three strains was consistent with the results from the Illumina MiSeq high throughput sequencing. The X-ray photoelectron spectroscopy results indicated that Fe(0) was transformed into Fe(II)/Fe(III) during the treatment process, which are beneficial for the microorganism growth, and thus promoting their metabolic processes and microbial community. PMID:28300176

  20. Helicobacter pylori seropositivity's association with markers of iron, 1-carbon metabolism, and antioxidant status among US adults: a structural equations modeling approach.

    Directory of Open Access Journals (Sweden)

    May A Beydoun

    Full Text Available We tested a model in which Helicobacter pylori seropositivity (Hps predicted iron status, which in turn acted as a predictor for markers of 1-C metabolism that were then allowed to predict antioxidant status.National Health and Nutrition Examination Surveys (NHANES 1999-2000 cross-sectional data among adults aged 20-85 y were analyzed (n = 3,055. Markers of Hps, iron status (serum ferritin and transferrin saturation (TS; 1-C metabolism (serum folate (FOLserum, B-12, total homocysteine (tHcy, methylmalonic acid (MMA and antioxidant status (vitamins A and E were entered into a structural equations model (SEM.Predictors of Hps included older age, lower education and income, racial/ethnic groups (lowest among Non-Hispanic Whites, and lifetime cigarette smoking. SEM modeling indicated that Hps had a direct inverse relationship with iron status (combining serum ferritin and TS which in turn was positively related to 1-C metabolites (higher serum folate, B-12 or lower tHcy/MMA that were positively associated with antioxidant status (combining serum vitamins A and E. Another pathway that was found bypassed 1-C metabolites (Hps → Iron_st → Antiox. The sum of all indirect effects from Hps combining both pathways and the other indirect pathways in the model (Hps → Iron_st → OneCarbon; Hps →OneCarbon →Antiox was estimated at β = -0.006±0.003, p<0.05.In sum, of the total effect of H. pylori seropositivity on antioxidant status, two significant indirect pathways through Iron status and 1-Carbon metabolites were found. Randomized controlled trials should be conducted to uncover the concomitant causal effect of H. pylori eradication on improving iron status, folate, B-12 and antioxidant status among H. pylori seropositive individuals.

  1. A cascade of iron-containing proteins governs the genetic iron starvation response to promote iron uptake and inhibit iron storage in fission yeast.

    Directory of Open Access Journals (Sweden)

    Javier Encinar del Dedo

    2015-03-01

    Full Text Available Iron is an essential cofactor, but it is also toxic at high levels. In Schizosaccharomyces pombe, the sensor glutaredoxin Grx4 guides the activity of the repressors Php4 and Fep1 to mediate a complex transcriptional response to iron deprivation: activation of Php4 and inactivation of Fep1 leads to inhibition of iron usage/storage, and to promotion of iron import, respectively. However, the molecular events ruling the activity of this double-branched pathway remained elusive. We show here that Grx4 incorporates a glutathione-containing iron-sulfur cluster, alone or forming a heterodimer with the BolA-like protein Fra2. Our genetic study demonstrates that Grx4-Fra2, but not Fep1 nor Php4, participates not only in iron starvation signaling but also in iron-related aerobic metabolism. Iron-containing Grx4 binds and inactivates the Php4 repressor; upon iron deprivation, the cluster in Grx4 is probably disassembled, the proteins dissociate, and Php4 accumulates at the nucleus and represses iron consumption genes. Fep1 is also an iron-containing protein, and the tightly bound iron is required for transcriptional repression. Our data suggest that the cluster-containing Grx4-Fra2 heterodimer constitutively binds to Fep1, and upon iron deprivation the disassembly of the iron cluster between Grx4 and Fra2 promotes reverse metal transfer from Fep1 to Grx4-Fra2, and de-repression of iron-import genes. Our genetic and biochemical study demonstrates that the glutaredoxin Grx4 independently governs the Php4 and Fep1 repressors through metal transfer. Whereas iron loss from Grx4 seems to be sufficient to release Php4 and allow its nuclear accumulation, total or partial disassembly of the Grx4-Fra2 cluster actively participates in iron-containing Fep1 activation by sequestering its iron and decreasing its interaction with promoters.

  2. Study of crystalline defects in α-iron

    International Nuclear Information System (INIS)

    Dunlop, A.

    1981-01-01

    We study here the configurations of the defects produced in ferromagnetic metals (Fe, Co, Ni) during low-temperature irradiations. In the first part we find an anomalous shape of the damage production rate curves Δrho(.)(Δrho) (Δrho: resistivity increase; Δrho(.)=dΔrho/dPHI; PHI: irradiation fluence) of iron and nickel during neutron irradiations. We propose the following interpretation: - stability of the defect configurations created during low-temperature self-ion irradiations of these metals; - instability of these defect configurations where there is a sufficient cascade overlap. This agglomeration leads to a decrease of the average resistivity of the defects. Using this model, we can reproduce the iron results with the following parameters: - characteristic volume for the recovery: 3.3 x 10 -18 cm 3 ; - division of the average resistivity of the defects by 2.3 to 3 when they agglomerate. In the second part we study the influence of irradiation defects on the longitudinal magnetoresistance of the samples. The increase in the number of scattering centers (n, e - irradiations) makes the resistivity anisotropy (deltarho=rho// - rho perpendicular) change gradually from a region in which the 'normal' magnetoresistance is predominant to another in which the spontaneous anisotropy dominates. This last regime is studied with the two-current conduction model in ferromagnetics [fr

  3. Iron signatures in Planetary Regoliths: The Moon as Case Study

    Science.gov (United States)

    McFadden, L. A.; Clark, P. E.; Basu, A.

    1998-09-01

    We consider the distribution of iron in the lunar crust by combining two complementary remote sensing techniques, Apollo Gamma-ray (AGR) spectroscopy and Clementine reflectance spectroscopy (CRS). Both maps were compared in areas of overlap controlled by Apollo 15 and 16 ground tracks. The CRS map was scaled to the same lower spatial resolution (200 km) as AGR using the same color map in a mercator projection. Both AGR and CRS maps show bimodal distributions of iron abundance and have large scale similarities, but there are quantitative and significant differences. Maria account for the high iron peak and highlands, the low iron peak. CSR-derived Fe has a greater overall range, very narrow modal peaks and greater separation between high and low modes compared to AGR Fe values. If both techniques measure total iron in the regolith then both approaches should agree, their residuals should be zero. After failure to explain the differences in a systematic manner, we recalibrated the CSR iron map to the iron abundance in the pyroxene component of Apollo landing site soils, an approach consistent with crystal field theory and the algorithm used to produce the CSR map. The difference between total iron measured by AGR and iron in pyroxene now measured by CSR gives a map of the non-pyroxene iron component of the lunar crust and its distribution. We now see a correlation with lunar morphology and an anti-correlation with age of mare basins and their iron abundance, the younger basins having a higher component of non-pyroxene iron than the older ones. These results can be checked with Lunar Prospector data on other areas of the Moon. Combining remote sensing data sets has promise for determining the distribution of iron in different oxidation states on Eros with data from the NEAR mission.

  4. Isotope - aided studies of the bioavailability of iron and zinc from human diets consumed in Poland

    International Nuclear Information System (INIS)

    Rafalski, H.

    1992-01-01

    The main aims of the study were: 1) the evaluation of iron and zinc status in women of Lodz aged 18-45 years, 2) adaptation of the whole body counter to in vivo measurements absorption of iron given to the gastro-intestinal tract of volunteers and 3) in rat model estimation iron bioavailability from fortified wheat flour combined with products usually consumed in Poland. During five months investigations thirty seven women were examined each one twice in two months interval. Following variables were measured: iron and zinc in blood serum, in public and scalp hair and in food, taste acuity score, serum ferritin, hemoglobin, total iron binding capacity, red blood cells, mean corpuscular concentration and corpuscular volume. Prevalence of iron deficiency and iron deficient anemia were assessed by two models in terms of the depression of serum ferritin and hemoglobin concentrations. 64 refs, 6 figs, 23 tabs

  5. Magnetization measurements and XMCD studies on ion irradiated iron oxide and core-shell iron/iron-oxide nanomaterials

    Energy Technology Data Exchange (ETDEWEB)

    Kaur, Maninder; Qiang, You; Jiang, Weilin; Pearce, Carolyn; McCloy, John S.

    2014-12-02

    Magnetite (Fe3O4) and core-shell iron/iron-oxide (Fe/Fe3O4) nanomaterials prepared by a cluster deposition system were irradiated with 5.5 MeV Si2+ ions and the structures determined by x-ray diffraction as consisting of 100% magnetite and 36/64 wt% Fe/FeO, respectively. However, x-ray magnetic circular dichroism (XMCD) indicates similar surfaces in the two samples, slightly oxidized and so having more Fe3+ than the expected magnetite structure, with XMCD intensity much lower for the irradiated core-shell samples indicating weaker magnetism. X-ray absorption spectroscopy (XAS) data lack the signature for FeO, but the irradiated core-shell system consists of Fe-cores with ~13 nm of separating oxide crystallite, so it is likely that FeO exists deeper than the probe depth of the XAS (~5 nm). Exchange bias (Hex) for both samples becomes increasingly negative as temperature is lowered, but the irradiated Fe3O4 sample shows greater sensitivity of cooling field on Hex. Loop asymmetries and Hex sensitivities of the irradiated Fe3O4 sample are due to interfaces and interactions between grains which were not present in samples before irradiation as well as surface oxidation. Asymmetries in the hysteresis curves of the irradiated core/shell sample are related to the reversal mechanism of the antiferromagnetic FeO and possibly some near surface oxidation.

  6. Experimental study and modelling of iron ore reduction by hydrogen

    International Nuclear Information System (INIS)

    Wagner, D.

    2008-01-01

    In an effort to find new ways to drastically reduce the CO 2 emissions from the steel industry (ULCOS project), the reduction of iron ore by pure hydrogen in a shaft furnace was investigated. The work consisted of literature, experimental, and modelling studies. The chemical reaction and its kinetics were analysed on the basis of thermogravimetric experiments and physicochemical characterizations of partially reduced samples. A specific kinetic model was designed, which simulates the successive reactions, the different steps of mass transport, and possible iron sintering, at the particle scale. Finally, a 2-dimensional numerical model of a shaft furnace was developed. It depicts the variation of the solid and gas temperatures and compositions throughout the reactor. One original feature of the model is using the law of additive characteristic times for calculating the reaction rates. This allowed us to handle both the particle and the reactor scale, while keeping reasonable calculation time. From the simulation results, the influence of the process parameters was assessed. Optimal operating conditions were concluded, which reveal the efficiency of the hydrogen process. (author)

  7. Metabolic studies of oxyguno in horses

    International Nuclear Information System (INIS)

    Wong, April S.Y.; Ho, Emmie N.M.; Wan, Terence S.M.; Lam, Kenneth K.H.; Stewart, Brian D.

    2015-01-01

    Oxyguno (4-chloro-17α-methyl-17β-hydroxy-androst-4-ene-3,11-dione) is a synthetic oral anabolic androgenic steroid commercially available without a prescription. Manufacturers of oxyguno claim that its anabolic effect in metabolic enhancement exceeds that of the classic anabolic steroid testosterone by seven times, but its androgenic side-effects are only twelve percent of testosterone. Like other anabolic androgenic steroids, oxyguno is prohibited in equine sports. The metabolism of oxyguno in either human or horse has not been reported and therefore little is known about its metabolic fate. This paper describes the in vitro and in vivo metabolic studies of oxyguno in racehorses with an objective to identify the most appropriate target metabolites for detecting oxyguno administration. In vitro studies of oxyguno were performed using horse liver microsomes. Metabolites in the incubation mixtures were isolated by liquid–liquid extraction and analysed by gas chromatography-mass spectrometry in the EI mode after trimethylsilylation. In vitro metabolites identified include the stereoisomers of 4-chloro-17α-methyl-androst-4-ene-3-keto-11,17β-diol (M1a & M1b); 20-hydroxy-oxyguno (M2); and 4-chloro-17α-methyl-androst-4-ene-3-keto-11,17β,20-triol (M3). These novel metabolites were resulted from hydroxylation at C20, and/or reduction of the keto group at C11. For the in vivo studies, two geldings were each administered orally with a total dose of 210 mg oxyguno (52.5 mg twice daily for 2 days). Pre- and post-administration urine and blood samples were collected for analysis. The parent drug oxyguno was detected in both urine and blood, while numerous novel metabolites were detected in urine. The stereoisomers (M1a & M1b) observed in the in vitro studies were also detected in post-administration urine samples. Three other metabolites (M4 - M6) were detected. M4, 4-chloro-17α-methyl-androstane-11-keto-3,17β-diol, was resulted from reductions of the olefin

  8. Metabolic studies of oxyguno in horses

    Energy Technology Data Exchange (ETDEWEB)

    Wong, April S.Y., E-mail: april.sy.wong-rl@hkjc.org.hk [Racing Laboratory, The Hong Kong Jockey Club, Sha Tin Racecourse, Sha Tin, N.T., Hong Kong (China); Ho, Emmie N.M. [Racing Laboratory, The Hong Kong Jockey Club, Sha Tin Racecourse, Sha Tin, N.T., Hong Kong (China); Wan, Terence S.M., E-mail: terence.sm.wan@hkjc.org.hk [Racing Laboratory, The Hong Kong Jockey Club, Sha Tin Racecourse, Sha Tin, N.T., Hong Kong (China); Lam, Kenneth K.H.; Stewart, Brian D. [Veterinary Regulation & International Liaison, The Hong Kong Jockey Club, Sha Tin Racecourse, Sha Tin, N.T, Hong Kong (China)

    2015-09-03

    Oxyguno (4-chloro-17α-methyl-17β-hydroxy-androst-4-ene-3,11-dione) is a synthetic oral anabolic androgenic steroid commercially available without a prescription. Manufacturers of oxyguno claim that its anabolic effect in metabolic enhancement exceeds that of the classic anabolic steroid testosterone by seven times, but its androgenic side-effects are only twelve percent of testosterone. Like other anabolic androgenic steroids, oxyguno is prohibited in equine sports. The metabolism of oxyguno in either human or horse has not been reported and therefore little is known about its metabolic fate. This paper describes the in vitro and in vivo metabolic studies of oxyguno in racehorses with an objective to identify the most appropriate target metabolites for detecting oxyguno administration. In vitro studies of oxyguno were performed using horse liver microsomes. Metabolites in the incubation mixtures were isolated by liquid–liquid extraction and analysed by gas chromatography-mass spectrometry in the EI mode after trimethylsilylation. In vitro metabolites identified include the stereoisomers of 4-chloro-17α-methyl-androst-4-ene-3-keto-11,17β-diol (M1a & M1b); 20-hydroxy-oxyguno (M2); and 4-chloro-17α-methyl-androst-4-ene-3-keto-11,17β,20-triol (M3). These novel metabolites were resulted from hydroxylation at C20, and/or reduction of the keto group at C11. For the in vivo studies, two geldings were each administered orally with a total dose of 210 mg oxyguno (52.5 mg twice daily for 2 days). Pre- and post-administration urine and blood samples were collected for analysis. The parent drug oxyguno was detected in both urine and blood, while numerous novel metabolites were detected in urine. The stereoisomers (M1a & M1b) observed in the in vitro studies were also detected in post-administration urine samples. Three other metabolites (M4 - M6) were detected. M4, 4-chloro-17α-methyl-androstane-11-keto-3,17β-diol, was resulted from reductions of the olefin

  9. Molecular modeling studies of oleate adsorption on iron oxides

    Energy Technology Data Exchange (ETDEWEB)

    Rath, Swagat S. [CSIR-Institute of Minerals and Materials Technology, Bhubaneswar (India); Sinha, Nishant [Accelrys K.K, Bengaluru (India); Sahoo, Hrushikesh [CSIR-Institute of Minerals and Materials Technology, Bhubaneswar (India); Das, Bisweswar, E-mail: bdas@immt.res.in [CSIR-Institute of Minerals and Materials Technology, Bhubaneswar (India); Mishra, Barada Kanta [CSIR-Institute of Minerals and Materials Technology, Bhubaneswar (India)

    2014-03-01

    Graphical abstract: - Highlights: • Plane wave periodic DFT study of oleate-iron oxide interaction. • Magnetite-oleate complex is more stable than hematite and goethite. • Flotation recovery of magnetite is more compared to the other two oxides. - Abstract: Comparative studies of oleate interaction with hematite, magnetite and goethite using density functional calculations are presented. The approach is illustrated by carrying out geometric optimization of oleate on the stable and most exposed planes of hematite, magnetite, and goethite. Interaction energies for oleate-mineral surface have been determined, based on which, magnetite is found to be forming the most stable complex with oleate. Trend as obtained from the quantum chemical calculations has been validated by contact angle measurements and flotation studies on hematite, magnetite and goethite with sodium oleate at different pH and collector concentrations.

  10. Molecular modeling studies of oleate adsorption on iron oxides

    International Nuclear Information System (INIS)

    Rath, Swagat S.; Sinha, Nishant; Sahoo, Hrushikesh; Das, Bisweswar; Mishra, Barada Kanta

    2014-01-01

    Graphical abstract: - Highlights: • Plane wave periodic DFT study of oleate-iron oxide interaction. • Magnetite-oleate complex is more stable than hematite and goethite. • Flotation recovery of magnetite is more compared to the other two oxides. - Abstract: Comparative studies of oleate interaction with hematite, magnetite and goethite using density functional calculations are presented. The approach is illustrated by carrying out geometric optimization of oleate on the stable and most exposed planes of hematite, magnetite, and goethite. Interaction energies for oleate-mineral surface have been determined, based on which, magnetite is found to be forming the most stable complex with oleate. Trend as obtained from the quantum chemical calculations has been validated by contact angle measurements and flotation studies on hematite, magnetite and goethite with sodium oleate at different pH and collector concentrations

  11. Iron sulphide containing hydrodesulfurization catalysts : Mössbauer study of the sulfidibility of alpha-iron(III) oxide

    NARCIS (Netherlands)

    Ramselaar, W.L.T.M.; Beer, de V.H.J.; Kraan, van der A.M.

    1988-01-01

    As a first step in the study of the sulphidation of carbon-supported iron oxide catalyst systems the sulphiding of a well-characterized, unsupported model compound, viz. a-Fe2O3(mean particle diameter ca. 50 nm) was investigated using in-situ Mössbauer spectroscopy and the temperature-programmed

  12. Iron minerals formed by dissimilatory iron-and sulfur reducing bacteria studied by Moessbauer spectrometry

    International Nuclear Information System (INIS)

    Chistyakova, N. I.; Rusakov, V. S.; Nazarova, K. A.; Koksharov, Yu. A.; Zavarzina, D. G.; Greneche, J.-M.

    2008-01-01

    Zero-field and in-field Moessbauer investigations and electron paramagnetic resonance (EPR) measurements to follow the kinetics of the iron mineral formation by thermophilic dissimilatory anaerobic Fe(III)-reducing bacteria (strain Z-0001) and anaerobic alkaliphilic bacteria (strain Z-0531) were carried out.

  13. COMPARATIVE STUDY OF EFFICACY OF FERROUS SULPHATE AND CARBONYL IRON IN ANEMIA OF ANTENATAL WOMEN

    Directory of Open Access Journals (Sweden)

    Radhika

    2015-03-01

    Full Text Available Iron deficiency anemia is the most common and important public health problem all over the world in the risk group of antenatal women. Research is going on to improve the iron status of the pregnant women with different forms of iron available. In this regard, Carbonyl Iron is showing promising results in improving the red cell mass with better compliance. 120 antenatal women were recruited in this study. The study comprised of 6weeks for each patient. They were given Carbonyl Iron 100 mg/day and FeS04 100gm/day . Before and after treatment all the baseline and specific investigations were one. Results were tabulated, comparison and significance were tested by unpaired student ’s’ test and their 'p' value was calculated. Results were shown graphically also. Carbonyl Iron showed improvement in hemoglobin, PCV and better than ferrous Sulphate (P <0.001. Incidence of side effects were less with Carbonyl Iron than Ferrous Sulphate, better compliance was seen with Carbonyl Iron. In conclusion, the present study s howed that Carbonyl Iron had better efficacy and safety in the management of Iron deficiency anemia in antenatal women than ferrous Sulphate

  14. The Moessbauer effect used to study iron minerals in Brazil

    International Nuclear Information System (INIS)

    Kunrath, J.I.

    1975-01-01

    The Moessbauer effect in Fe 57 was used to study iron minerals in Brazil. More than 50 samples were analyzed in this preliminary work. Although many minerals present complex spectra, it was possible to find a number of samples with relatively pure natural materials, which may be considered representative of the simple compounds that enter as constituents in the more complex cases. Important and, in some cases, drastic differences were found between spectra at room and liquid nitrogen temperatures. These differences are reported and in some cases explained. Another feature was the difference in the Moessbauer effect spectra, observable when some crystallization water is present. This phenomenon is correlated to the previous one. The methodology of this study is also reported [pt

  15. Metabolic and improved organ scan studies. III. 13N-ammonia metabolic studies in hepatic encephalopathy

    International Nuclear Information System (INIS)

    Anon.

    1976-01-01

    Results are reported from an investigation into the nature of hepatic encephalopathy, through study of the uptake and metabolism of 13 N-labeled ammonia by the brain in relation to liver function, in order to develop improved methods for the management of patients with this condition

  16. Studies on Ferrokinetics and Copper Metabolism in Various Malignant Tumors

    International Nuclear Information System (INIS)

    Kim, Yong Kyu

    1967-01-01

    Anemia is a usual finding in advanced malignant diseases. Various mechanisms were reported as to be involved in the development of anemia of this kind, and they may differ in individual cases. Tumor anemias may be due, for instance, to chronic blood loss, shortened life span of the red blood cells or a decreased hemopoiesis in the bone marrow. The serum iron and copper levels, total iron binding capacity, apparent half survival of 51 Cr-labelled red blood cells were measurement with the ferrokinetic studies using 59 Fe in 64 patients with various malignant tumors. Following were the results: 1) The serum iron levels were decreased in all cases. There existed no correlation between the serum iron levels and the severity of the diseases. 2) The serum copper levels were increased, particularly in lung cancer, rectal cancer, hepatoma and various sarcomas. There was also no correlation between the serum copper levels and the severity of the diseases. 3) The serum iron levels appeared to be inversely proportional to the serum copper levels. 4) The total iron binding capacities were within normal limits in all cases. There were also no correlations between the total iron binding capacities, serum iron levels and the severity of the diseases. 5) The patients could be classified according the ferrokinetic patterns, namely, that of iron deficiency anemia in 10 cases, that of refractory anemia in 6 cases, normal in 1 case and that of atypical abnormal in 9 cases. 6) Apparent half survival time of 51 Cr-labelled red blood cells were definitely shortened in half of the cases.

  17. Iron supplementation in Switzerland - A bi-national, descriptive and observational study.

    Science.gov (United States)

    Biétry, Fabienne A; Hug, Balthasar; Reich, Oliver; Susan, Jick S; Meier, Christoph Rudolf

    2017-07-11

    Iron deficiency is the most common nutritional disorder in the world, and it is the only common nutrient deficiency in industrialised nations. It is thought to be the most common cause of anaemia. Use of iron supplementation in Switzerland has not been previously quantified in detail. We quantified use of iron supplementation from Swiss data and compared it with data from the UK. We assessed the frequency of serum ferritin and haemoglobin tests prior to newly started iron therapy to see whether use was based on documented low iron levels or blood parameters, especially in the case of parenteral iron supplementation. We conducted a retrospective descriptive study of prescription iron supplementation use, and compared use of oral or parenteral iron drugs between Switzerland (CH) and the UK. We retrieved Swiss data from the Swiss Health Insurance Helsana Group, and UK data were from the Clinical Practice Research Datalink (CPRD). The study period was 2012 to 2014. The 3-year prevalence of iron supplementation was 9.4% in Switzerland and 4.4% in the UK. Iron use increased slightly between 2012 and 2014 in both countries (CH +0.3%, UK +0.2%). Recorded parenteral iron administration was roughly a thousand times higher in Switzerland (1.9%) than in the UK in 2014. In Switzerland, iron supplements were mostly given to patients aged 20 to 49 years or older than of 80 years. In the UK, iron supplementation was less frequent in younger people, but more prevalent in the elderly. Prior to a first iron prescription, ferritin tests were done more frequently in Switzerland (oral 67.2%, parenteral 86.6%) than in the UK (oral 43.3%, parenteral 65.5%). Haemoglobin was measured before a new parenteral iron therapy rarely in Switzerland (oral 14.9%, parenteral 11.7%), but frequently in the UK (oral 77.4%, parenteral 85.6%). Iron supplementation is more common in Switzerland than in the UK, particularly parenteral iron supplementation. Haemoglobin measurements prior to a new parenteral

  18. Studies on effect of Microbial Iron Chelators on Candida Albican

    International Nuclear Information System (INIS)

    Rehmani, Fouzia S.; Milicent, S.; Zaheer-Uddin

    2005-01-01

    Iron is an essential for the life of all microbe cells. It generally exists in the oxidized form Fe(III). Even under anaerobic reducing condition the metal appear to be taken up as Fe(III). Thus free-living microorganisms require specific and effective ferric ion transport system to cope with low availability of the metal. In iron deficient environment they produce a low molecular weight specific chelators called siderphores or microbial iron chelators. Siderphores compete for limited supplied of iron. These compounds came out of the cell but can not re-enter without iron due to high affinity of these siderphores often have more than one catechol/hydroxamate functions and are multidentate (usually hexadentate ligands). The aim of the present research is to check the effect of iron chelators, namely gallic acid and salisyl hydroxamate on the growth of Candida albican in vitro. C. albican is the opportunistic paltogen present as the normal flora inside human body. In vivo the growth of C. albican is distributed by the use of antibiotics and immuno suppressers. In cases of iron over-dosage in human being, the patients are treated with certain a-iron chelators. Hence an attempt is made to notice the effect that might be inhibition or enhancement of the organism in vitro. (author)

  19. Adsorption studies of iron(III) on chitin

    Indian Academy of Sciences (India)

    Unknown

    of particle size and dosage of the adsorbant, contact time, initial concentration of the adsorbate and tem- perature were experimentally ... Adsorption; chitin; variable parameters; fraction of adsorption; temperature effect. 1. Introduction. Iron is one of the ... about the presence of iron in drinking water is its ob- jectionable taste.

  20. Moessbauer study of iron-cobalt-rhodium spinels

    Energy Technology Data Exchange (ETDEWEB)

    Spencer, C D; Smith, P A; Karnes, C M; Shepard, W A [Ithaca Coll., NY (USA). Dept. of Physics

    1980-01-01

    Moessbauer source and absorber studies have been carried out on the spinel system CoFesub(x)Rhsub(2-x)O/sub 4/ for x 0.005, 0.3, 0.5, 1.0, 1.2 and 1.5. For 0.005 =< x =< 1.2, the cation distribution is normal with Co/sup 2 +/ on A sites. At x = 1.5, the distribution is nearly inverse. In the cases x = 0.005 and 0.3, iron on the B sites does not produce a quadrupole doublet indicating that the B sites are cubic which is contrary to the usual case in spinels.

  1. Causes of iron overload in blood donors - a clinical study

    DEFF Research Database (Denmark)

    Laursen, A H; Bjerrum, O W; Friis-Hansen, L

    2018-01-01

    BACKGROUND AND OBJECTIVES: Despite the obligate iron loss from blood donation, some donors present with hyperferritinaemia that can result from a wide range of acute and chronic conditions including hereditary haemochromatosis (HH). The objective of our study was to investigate the causes...... of hyperferritinaemia in the blood donor population and explore the value of extensive HH mutational analyses. MATERIALS AND METHODS: Forty-nine consecutive donors (f = 6, m = 43) were included prospectively from the Capital Regional Blood Center. Inclusion criteria were a single ferritin value >1000 μg/l or repeated...... four donors had apparent alternative causes of hyperferritinaemia. CONCLUSION: HH-related mutations were the most frequent cause of hyperferritinaemia in a Danish blood donor population, and it appears that several different HH-genotypes can contribute to hyperferritinaemia. HH screening in blood...

  2. A study of DLC coatings for ironing of stainless steel

    Science.gov (United States)

    Sulaiman, M. H.; Christiansen, P.; Bay, N.

    2017-09-01

    Stamping of sheet metal components without lubrication or using minimum amount of hazard free lubricant is a possible solution to diminish health hazards to personnel and environmental impact and to reduce production costs. This paper studies the application of diamond-like coating (DLC) under severe lubrication conditions by adopting strip reduction testing to replicate industrial ironing production of deep drawn, stainless steel cans. Three DLC coatings are investigated; multi-layer, double layer and single layer. Experiments revealed that the double layer coating worked successful, i.e. with no sign of galling using no lubrication even at elevated tool temperature, while the other two coatings peeled off and resulted in severe galling unless lubrication was applied.

  3. Iron in Alzheimer's and Control Hippocampi - Moessbauer, Atomic Absorption and ELISA Studies

    International Nuclear Information System (INIS)

    Galazka-Friedman, J.; Szlachta, K.; Bauminger, E.R.; Koziorowski, D.; Friedman, A.; Tomasiuk, R.; Jaklewicz, A.; Wszolek, Z.K.; Dickson, D.; Kaplinska, K.

    2011-01-01

    Alzheimer disease is a neurodegenerative process of unknown mechanism taking place in a part of the brain - hippocampus. Oxidative stress and the role of iron in it is one of the suggested mechanisms of cells death. In this study several methods were used to assess iron and iron binding compounds in human hippocampus tissues. Moessbauer spectroscopy was used for identification of the iron binding compound and determination of total iron concentration in 12 control and one Alzheimer disease sample of hippocampus. Moessbauer parameters obtained for all samples suggest that most of the iron is ferritin-like iron. The average concentration of iron determined by Moessbauer spectroscopy in control hippocampus was 45 ± 10 ng/mg wet tissue. The average concentration of iron in 10 Alzheimer disease samples determined by atomic absorption was 66 ± 13 ng/mg wet tissue. The concentration of H and L chains of ferritin in 20 control and 10 AD hippocampi was assessed with enzyme-linked immuno-absorbent assay. The concentration of H and L ferritin was higher in Alzheimer disease compared to control (19.36 ± 1.51 vs. 5.84 ± 0.55 ng/μg protein for H, and 1.39 ± 0.25 vs. 0.55 ± 0.10 for L). This 3-fold increase of the concentration of ferritin is accompanied by a small increase of the total iron concentration. (authors)

  4. F-radiographic study of uranium distribution in iron hydroxides from crusts of weathering

    International Nuclear Information System (INIS)

    Zhmodik, S.M.; Mironov, A.G.; Nemirovskaya, N.A.

    1980-01-01

    Presented are the results of study of uranium concentrations and peculiarities of its distribution in iron hydroxides from crusts of weathering of aluminium silicate and carbonate rocks. The age of one crusts of weathering is Quaternary, of others - Tertiary. The effect of climatic conditions, composition of source rocks, hydrochemical zoning of the crust of weathering on the uranium fixation by iron hydroxides has been studied. Gamma-spectroscopy, luminescence and autoradiography methods have been used. The mechanism of formation of increased uranium concentrations in iron hydroxides is considered. A conclusion is made that increased uranium concentrations in iron hydroxides may appear in the process of weathering both of aluminium-silicate and carbonate-containing rocks as a result of uranium sorption by fine dispersed iron hydrates. The use of iron hydroxides with increased (anomalous) uranium concentrations as a direct search feature without additional investigations can lead to wrong conclusions

  5. Serum iron levels and the risk of Parkinson disease: a Mendelian randomization study.

    Directory of Open Access Journals (Sweden)

    Irene Pichler

    Full Text Available Although levels of iron are known to be increased in the brains of patients with Parkinson disease (PD, epidemiological evidence on a possible effect of iron blood levels on PD risk is inconclusive, with effects reported in opposite directions. Epidemiological studies suffer from problems of confounding and reverse causation, and mendelian randomization (MR represents an alternative approach to provide unconfounded estimates of the effects of biomarkers on disease. We performed a MR study where genes known to modify iron levels were used as instruments to estimate the effect of iron on PD risk, based on estimates of the genetic effects on both iron and PD obtained from the largest sample meta-analyzed to date.We used as instrumental variables three genetic variants influencing iron levels, HFE rs1800562, HFE rs1799945, and TMPRSS6 rs855791. Estimates of their effect on serum iron were based on a recent genome-wide meta-analysis of 21,567 individuals, while estimates of their effect on PD risk were obtained through meta-analysis of genome-wide and candidate gene studies with 20,809 PD cases and 88,892 controls. Separate MR estimates of the effect of iron on PD were obtained for each variant and pooled by meta-analysis. We investigated heterogeneity across the three estimates as an indication of possible pleiotropy and found no evidence of it. The combined MR estimate showed a statistically significant protective effect of iron, with a relative risk reduction for PD of 3% (95% CI 1%-6%; p = 0.001 per 10 µg/dl increase in serum iron.Our study suggests that increased iron levels are causally associated with a decreased risk of developing PD. Further studies are needed to understand the pathophysiological mechanism of action of serum iron on PD risk before recommendations can be made.

  6. The effect of gold kiwifruit consumed with an iron fortified breakfast cereal meal on iron status in women with low iron stores: A 16 week randomised controlled intervention study

    Directory of Open Access Journals (Sweden)

    Coad Jane

    2010-01-01

    Full Text Available Abstract Background Dietary treatment is often recommended as the first line of treatment for women with mild iron deficiency. Although it is well established that ascorbic acid enhances iron absorption, it is less clear whether the consumption of ascorbic acid rich foods (such as kiwifruit with meals fortified with iron improves iron status. The aim of this study is to investigate whether the consumption of ZESPRI® GOLD kiwifruit (a fruit high in ascorbic acid and carotenoids with an iron fortified breakfast cereal meal increases iron status in women with low iron stores. Methods/Design Eighty nine healthy women aged 18-44 years with low iron stores (serum ferritin (SF ≤ 25 μg/L, haemoglobin (Hb ≥ 115 g/L living in Auckland, New Zealand were randomised to receive an iron fortified breakfast cereal (16 mg iron per serve and either two ZESPRI® GOLD kiwifruit or a banana (low ascorbic acid and carotenoid content to eat at breakfast time every day for 16 weeks. Iron status (SF, Hb, C-reactive protein (CRP and soluble transferrin receptor (sTfR, ascorbic acid and carotenoid status were measured at baseline and after 16 weeks. Anthropometric measures, dietary intake, physical activity and blood loss were measured before and after the 16 week intervention. Discussion This randomised controlled intervention study will be the first study to investigate the effect of a dietary based intervention of an iron fortified breakfast cereal meal combined with an ascorbic acid and carotenoid rich fruit on improving iron status in women with low iron stores. Trial registration ACTRN12608000360314

  7. 4-Hydroxy-2(E)-nonenal metabolism differs in Apc(+/+) cells and in Apc(Min/+) cells: it may explain colon cancer promotion by heme iron.

    Science.gov (United States)

    Baradat, Maryse; Jouanin, Isabelle; Dalleau, Sabine; Taché, Sylviane; Gieules, Mathilde; Debrauwer, Laurent; Canlet, Cécile; Huc, Laurence; Dupuy, Jacques; Pierre, Fabrice H F; Guéraud, Françoise

    2011-11-21

    Animal and epidemiological studies suggest that dietary heme iron would promote colorectal cancer. Oxidative properties of heme could lead to the formation of cytotoxic and genotoxic secondary lipid oxidation products, such as 4-hydroxy-2(E)-nonenal (HNE). This compound is more cytotoxic to mouse wild-type colon cells than to isogenic cells with a mutation on the adenomatous polyposis coli (APC) gene. The latter thus have a selective advantage, possibly leading to cancer promotion. This mutation is an early and frequent event in human colorectal cancer. To explain this difference, the HNE biotransformation capacities of the two cell types have been studied using radiolabeled and stable isotope-labeled HNE. Apc-mutated cells showed better biotransformation capacities than nonmutated cells did. Thiol compound conjugation capacities were higher for mutated cells, with an important advantage for the extracellular conjugation to cysteine. Both cells types were able to reduce HNE to 4-hydroxynonanal, a biotransformation pathway that has not been reported for other intestinal cells. Mutated cells showed higher capacities to oxidize 4-hydroxynonanal into 4-hydroxynonanoic acid. The mRNA expression of different enzymes involved in HNE metabolism such as aldehyde dehydrogenase 1A1, 2 and 3A1, glutathione transferase A4-4, or cystine transporter xCT was upregulated in mutated cells compared with wild-type cells. In conclusion, this study suggests that Apc-mutated cells are more efficient than wild-type cells in metabolizing HNE into thiol conjugates and 4-hydroxynonanoic acid due to the higher expression of key biotransformation enzymes. These differential biotransformation capacities would explain the differences of susceptibility between normal and Apc-mutated cells regarding secondary lipid oxidation products.

  8. Contribution to the study of the electrodeposition of iron-nickel alloys

    International Nuclear Information System (INIS)

    Valignat, J.

    1968-01-01

    Using a coulometric technique based upon the anodic intentiostatic dissolution, we studied the potentiostatic, deposition of nickel, iron and nickel iron alloys. We have shown that the minimum of the curve I = f (t) (deposition current versus time) is probably due to the transitory blocking of the surface by hydrogen and that the syn-crystallisation of nickel and iron is responsible for the anomalous co-deposition of these two elements. (author) [fr

  9. The FIND-CKD study--a randomized controlled trial of intravenous iron versus oral iron in non-dialysis chronic kidney disease patients: background and rationale.

    Science.gov (United States)

    Macdougall, Iain C; Bock, Andreas; Carrera, Fernando; Eckardt, Kai-Uwe; Gaillard, Carlo; Van Wyck, David; Roubert, Bernard; Cushway, Timothy; Roger, Simon D

    2014-04-01

    Rigorous data are sparse concerning the optimal route of administration and dosing strategy for iron therapy with or without concomitant erythropoiesis-stimulating agent (ESA) therapy for the management of iron deficiency anaemia in patients with non-dialysis dependent chronic kidney disease (ND-CKD). FIND-CKD was a 56-week, open-label, multicentre, prospective, randomized three-arm study (NCT00994318) of 626 patients with ND-CKD and iron deficiency anaemia randomized to (i) intravenous (IV) ferric carboxymaltose (FCM) at an initial dose of 1000 mg iron with subsequent dosing as necessary to target a serum ferritin level of 400-600 µg/L (ii) IV FCM at an initial dose of 200 mg with subsequent dosing as necessary to target serum ferritin 100-200 µg/L or (iii) oral ferrous sulphate 200 mg iron/day. The primary end point was time to initiation of other anaemia management (ESA therapy, iron therapy other than study drug or blood transfusion) or a haemoglobin (Hb) trigger (two consecutive Hb values FIND-CKD was the longest randomized trial of IV iron therapy to date. Its findings will address several unanswered questions regarding iron therapy to treat iron deficiency anaemia in patients with ND-CKD. It was also the first randomized trial to utilize both a high and low serum ferritin target range to adjust IV iron dosing, and the first not to employ Hb response as its primary end point.

  10. Four variants in transferrin and HFE genes as potential markers of iron deficiency anaemia risk: an association study in menstruating women

    Directory of Open Access Journals (Sweden)

    Arroyo-Pardo Eduardo

    2011-10-01

    Full Text Available Abstract Background Iron deficiency anaemia is a worldwide health problem in which environmental, physiologic and genetic factors play important roles. The associations between iron status biomarkers and single nucleotide polymorphisms (SNPs known to be related to iron metabolism were studied in menstruating women. Methods A group of 270 Caucasian menstruating women, a population group at risk of iron deficiency anaemia, participated in the study. Haematological and biochemical parameters were analysed and 10 selected SNPs were genotyped by minisequencing assay. The associations between genetic and biochemical data were analysed by Bayesian Model Averaging (BMA test and decision trees. Dietary intake of a representative subgroup of these volunteers (n = 141 was assessed, and the relationship between nutrients and iron biomarkers was also determined by linear regression. Results Four variants, two in the transferrin gene (rs3811647, rs1799852 and two in the HFE gene (C282Y, H63D, explain 35% of the genetic variation or heritability of serum transferrin in menstruating women. The minor allele of rs3811647 was associated with higher serum transferrin levels and lower transferrin saturation, while the minor alleles of rs1799852 and the C282Y and H63D mutations of HFE were associated with lower serum transferrin levels. No association between nutrient intake and iron biomarkers was found. Conclusions In contrast to dietary intake, these four SNPs are strongly associated with serum transferrin. Carriers of the minor allele of rs3811647 present a reduction in iron transport to tissues, which might indicate higher iron deficiency anaemia risk, although the simultaneous presence of the minor allele of rs1799852 and HFE mutations appear to have compensatory effects. Therefore, it is suggested that these genetic variants might potentially be used as markers of iron deficiency anaemia risk.

  11. Isotope-aided studies of the bioavailability of iron from Myanmar diets

    International Nuclear Information System (INIS)

    Khin Maung Naing; Myo Khin

    1994-01-01

    A study was conducted to determine the dietary intakes and serum levels of iron and zinc in twenty apparently healthy Myanmar adults (10 males and 10 females), using atomic absorption spetrophotometry. The mean iron intake of females was found to be lower than the FAO/WHO recommended allowance whereas for men it was found to be adequate. The mean serum iron concentration in females was found to be significantly lower than in males (p 4· 7H 2 O, and 5g of sodium-hexa-metaphosphate thoroughly and then the mixture was again mixed with 1 kg of salt. This was done in July 1992. The stability of iron-fortified salt (i.e. change in colour of salt) as well as ferrous and ferric iron content of iron-fortified salt, were determined at monthly intervals. The iron-fortified salt was found to be stable up to the time of report writing, i.e. 3rd week of October, 1992. The ferrous iron content of salt was found to range between 0.95 to 0.98 mg Fe/g salt. Bioavailability studies of iron from two types of standard meals, one containing staple rice, 32 g of fish, water cress, watery fish paste and cucumber, and another containing boiled peas in place of fish, were conducted on two groups of male subjects using 59 Fe as an extrinsic tag. Bioavailability studies of iron from the above two types of meals cooked with iron-fortified salt (1 mg/g salt) were also conducted on the same groups of subjects using 59 Fe as an extrinsic tag. Reference dose absorption of iron will be conducted. This work is in progress. (author). 6 refs, 4 tabs

  12. Isotope aided studies of the bioavailability of iron and zinc from human diets consumed in Peru

    International Nuclear Information System (INIS)

    Zavaleta, N.; Penny, M.; Berlanga, R.; Espinoza, R.; Lonnerdal, B.

    1992-01-01

    Iron deficiency can produce disturbances in physical and mental health, the most common sign of severe iron deficiency being anaemia. Iron deficiency anaemia can impair work capacity; learning capacity and result in changes in behaviour as well as compromise immunocompetence and causing less resistance to infections. In pregnancy, there is evidence that severe anaemia increases the risk of maternal morbidity and mortality as well as premature delivery. There is thus ample justification for attempting to implement programmes to combat iron deficiency in developing countries such as Peru. In order to determine the most appropriate intervention it is necessary to have data on the prevalence and severity of iron deficiency. The purpose of this study is to develop the necessary steps to implement a fortification programme to combat iron deficiency anaemia in Peru, targeted to pre-school children and pregnant women, who are the risk groups due to their increased requirements of this nutrient. 11 refs, 6 figs, 6 tabs

  13. Relationships among personality traits, metabolic syndrome, and metabolic syndrome scores: The Kakegawa cohort study.

    Science.gov (United States)

    Ohseto, Hisashi; Ishikuro, Mami; Kikuya, Masahiro; Obara, Taku; Igarashi, Yuko; Takahashi, Satomi; Kikuchi, Daisuke; Shigihara, Michiko; Yamanaka, Chizuru; Miyashita, Masako; Mizuno, Satoshi; Nagai, Masato; Matsubara, Hiroko; Sato, Yuki; Metoki, Hirohito; Tachibana, Hirofumi; Maeda-Yamamoto, Mari; Kuriyama, Shinichi

    2018-04-01

    Metabolic syndrome and the presence of metabolic syndrome components are risk factors for cardiovascular disease (CVD). However, the association between personality traits and metabolic syndrome remains controversial, and few studies have been conducted in East Asian populations. We measured personality traits using the Japanese version of the Eysenck Personality Questionnaire (Revised Short Form) and five metabolic syndrome components-elevated waist circumference, elevated triglycerides, reduced high-density lipoprotein cholesterol, elevated blood pressure, and elevated fasting glucose-in 1322 participants aged 51.1±12.7years old from Kakegawa city, Japan. Metabolic syndrome score (MS score) was defined as the number of metabolic syndrome components present, and metabolic syndrome as having the MS score of 3 or higher. We performed multiple logistic regression analyses to examine the relationship between personality traits and metabolic syndrome components and multiple regression analyses to examine the relationship between personality traits and MS scores adjusted for age, sex, education, income, smoking status, alcohol use, and family history of CVD and diabetes mellitus. We also examine the relationship between personality traits and metabolic syndrome presence by multiple logistic regression analyses. "Extraversion" scores were higher in those with metabolic syndrome components (elevated waist circumference: P=0.001; elevated triglycerides: P=0.01; elevated blood pressure: P=0.004; elevated fasting glucose: P=0.002). "Extraversion" was associated with the MS score (coefficient=0.12, P=0.0003). No personality trait was significantly associated with the presence of metabolic syndrome. Higher "extraversion" scores were related to higher MS scores, but no personality trait was significantly associated with the presence of metabolic syndrome. Copyright © 2018 Elsevier Inc. All rights reserved.

  14. Synthesis and Stability of Iron Nanoparticles for Lunar Environment Studies

    Science.gov (United States)

    Hung, Ching-cheh; McNatt, Jeremiah

    2009-01-01

    Simulant of lunar dust is needed when researching the lunar environment. However, unlike the true lunar dust, today s simulants do not contain nanophase iron. Two different processes have been developed to fabricate nanophase iron to be used as part of the lunar dust simulant: (1) Sequentially treating a mixture of ferric chloride, fluorinated carbon, and soda lime glass beads at about 300 C in nitrogen, at room temperature in air, and then at 1050 C in nitrogen. The product includes glass beads that are grey in color, can be attracted by a magnet, and contain alpha-iron nanoparticles (which seem to slowly lose their lattice structure in ambient air during a period of 12 months). This product may have some similarity to the lunar glassy regolith that contains Fe(sup 0). (2) Heating a mixture of carbon black and a lunar simulant (a mixed metal oxide that includes iron oxide) at 1050 C in nitrogen. This process simulates lunar dust reaction to the carbon in a micrometeorite at the time of impact. The product contains a chemically modified simulant that can be attracted by a magnet and has a surface layer whose iron concentration increased during the reaction. The iron was found to be alpha-iron and Fe3O4 nanoparticles, which appear to grow after the fabrication process, but stabilizes after 6 months of ambient air storage.

  15. Study of the fallout of artificial iron-55. Application to the evaluation of the fallout of natural iron of stratospheric origin

    International Nuclear Information System (INIS)

    Hoang Chi Trach

    1969-01-01

    The object of this work is to study the iron-55 fallout to establish the world balance of this radioelement. The utilisation of this tracer enables the calculation of the input of natural iron of stratospheric origin to the Earth and the input through the atmosphere of natural iron to the oceans. We have shown that: iron-55 is essentially produced in nuclear explosions according to the 56 Fe(n,2n) 55 Fe reaction; the iron-55 fallout obeys a 'stratospheric pattern' with a decay period between 9 and 11 months; by surface unit and at the same latitude, this fallout is 3.5 times more important on the Eastern part of the Northern Atlantic than over France. By comparison with the strontium-90 fallout, we established the world balance of the iron-55 fallout in the 1962-1965 period. This balance amounts to approximately 50 mega-curies for the iron-55 introduced into the atmosphere; 25.3 mega-curies of which fall down on the Earth during this period. We estimated at 6 x 10 6 tons per year the input of natural iron of stratospheric origin to the Earth and at 1.2 x 10 7 tons per year the input through the atmosphere of natural iron to the oceans. This latter figure represents 13 to 38 per cent of the amount of iron incorporated annually in the pelagic sediments. (author) [fr

  16. INTRAVENOUS IRON-SUCROSE COMPLEX THERAPY IN PREGNANT WOMEN WITH IRON DEFICIENCY ANAEMIA- A STUDY IN TERTIARY CENTRE

    Directory of Open Access Journals (Sweden)

    Todak Taba

    2017-11-01

    Full Text Available BACKGROUND Anaemia in pregnancy continues to be a major public health problem with 54.96% of the pregnant population suffering from it in our setup. Despite the National Anaemia Prophylaxis Programme, anaemia complicating pregnancy continues to be a widespread problem with adverse effects on maternal and foetal outcome. The aim of the study is to find out an alternate iron therapy in the form of intravenous iron-sucrose and to determine its therapeutic effectiveness, safety and compliance in the management of anaemic expectant mother and to compare it with that of conventional oral iron therapy. MATERIALS AND METHODS The study was a randomised controlled clinical trial carried out in the Department of Obstetrics and Gynaecology in collaboration with the Department of Biochemistry, Regional Institute of Medical Sciences (RIMS, Imphal. 100 pregnant women in second or third trimester with mild or moderate anaemia were selected, 50 as study group (intravenous iron and 50 as controls (oral iron. Initial evaluation included complete blood count and serum ferritin level and reevaluated on the 14th and 28th day of initiation of therapy. RESULTS Majority of patients (42% in the study as well as control group were between 26-30 years of age. The mean ± SD increase in haemoglobin and ferritin levels on 28th day were 2.66 ± 0.34 gm/dL and 27.65 ± 1.80 ng/mL in study group and 1.55 ± 0.23 gm/dL and 16.89 ± 0.76 ng/mL in control group respectively, both of which were statistically significant. CONCLUSION The mean haemoglobin and serum ferritin levels throughout the treatment were significantly higher in the intravenous ironsucrose group than in the orally administered iron group and significantly higher number of patients achieved the target haemoglobin of 11.0 gm/dL after 28 days of treatment. This reduces the blood transfusion rates in pregnant women with severe anaemia near term.

  17. Contribution to the study of iron-manganese alloy oxidation in oxygen at high temperatures

    International Nuclear Information System (INIS)

    Olivier, Francoise

    1972-01-01

    This research thesis reports a systematic investigation of the oxidation of three relatively pure iron-manganese alloys in oxygen, under atmospheric pressure, and between 400 and 1000 C, these alloys being annealed as well as work-hardened. It also compares their behaviour with that of non-alloyed iron oxidized under the same conditions. The author describes the experimental techniques and installations, discusses the morphology of oxide films formed under the experimental conditions, discusses the film growth kinetics which is studied by thermogravimetry, proposes interpretations of results, and outlines the influence of manganese addition to iron on iron oxidation

  18. Moessbauer study of ancient iron smelting slag in Japan

    International Nuclear Information System (INIS)

    Nakanishi, A.

    2008-01-01

    For an investigation of the ancient iron manufacturing technique, a reproducing experiment was carried out by archaeologists, where ancient type of iron smelting furnace was built and iron sand with high titanium contents was used as the raw material. During the operation of furnace, a large amount of slag flowed away from the furnace. In order to investigate the possibility for the estimation about the operative condition of furnace and the raw material, 57 Fe Moessbauer spectroscopy was applied for characterizing these slags and it was found that these slags mainly consisted of ferropseudobrookite (FeTi 2 O 5 ).

  19. Urinary hepcidin level as an early predictor of iron deficiency in children: A case control study

    Directory of Open Access Journals (Sweden)

    Gharib Amal F

    2011-08-01

    Full Text Available Abstract Background The ideal screening test would be capable of identifying iron deficiency in the absence of anemia. We tried to detect role of urinary hepcidin-25 level in early prediction of iron deficiency in children. Methods This is a case control study performed on 100 children in Hematology Unit of Pediatric Department, Zagazig University Hospital, Egypt. Our study included 25 cases of iron deficiency (ID stage-1 (iron depletion, 25 cases ID stage-2 (iron-deficient erythropoiesis, 25 cases ID stage-3 (iron deficiency anemia and 25 healthy children as a control group. Estimation of iron status parameters was done. Urinary hepcidin-25 level was detected. Results Urinary hepcidin-25 level was significantly lower in all stages of iron deficiency than in control group, more significant reduction in its level was observed with the progress in severity of iron deficiency. Urinary hepcidin showed significant positive correlation with hemoglobin, mean corpuscular volume, hematocrit value, serum iron and ferritin and transferrin saturation. In contrary, it showed significant negative correlation with serum transferrin and total iron binding capacity. Urinary hepcidin at cutoff point ≤0.94 nmol/mmol Cr could Predict ID stage-1 with sensitivity 88% and specificity 88%. Cutoff point ≤0.42 nmol/mmol Cr could predict ID stage-2 with sensitivity 96% and specificity 92%. Cutoff point ≤0.08 nmol/mmol Cr could Predict ID stage-3 with Sensitivity 96% and specificity 100%. Conclusions We can conclude that detection of urinary hepcidin-25 level was a simple and non invasive test and could predict iron deficiency very early, before appearance of hematological affections.

  20. Metabolism

    Science.gov (United States)

    ... Are More Common in People With Type 1 Diabetes Metabolic Syndrome Your Child's Weight Healthy Eating Endocrine System Blood Test: Basic Metabolic Panel (BMP) Activity: Endocrine System Growth Disorders Diabetes Center Thyroid Disorders Your Endocrine System Movie: Endocrine ...

  1. Metabolic studies in man using stable isotopes

    International Nuclear Information System (INIS)

    Faust, H.; Jung, K.; Krumbiegel, P.

    1993-01-01

    In this project, stable isotope compounds and stable isotope pharmaceuticals were used (with emphasis on the application of 15 N) to study several aspects of nitrogen metabolism in man. Of the many methods available, the 15 N stable isotope tracer technique holds a special position because the methodology for application and nitrogen isotope analysis is proven and reliable. Valid routine methods using 15 N analysis by emission spectrometry have been demonstrated. Several methods for the preparation of biological material were developed during our participation in the Coordinated Research Programme. In these studies, direct procedures (i.e. use of diluted urine as a samples without chemical preparation) or rapid isolation methods were favoured. Within the scope of the Analytical Quality Control Service (AQCS) enriched stable isotope reference materials for medical and biological studies were prepared and are now available through the International Atomic Energy Agency. The materials are of special importance as the increasing application of stable isotopes as tracers in medical, biological and agricultural studies has focused interest on reliable measurements of biological material of different origin. 24 refs

  2. Association of dietary and supplemental iron and colorectal cancer in a population-based study.

    Science.gov (United States)

    Ashmore, Joseph H; Lesko, Samuel M; Miller, Paige E; Cross, Amanda J; Muscat, Joshua E; Zhu, Junjia; Liao, Jason; Harper, Gregory; Lazarus, Philip; Hartman, Terryl J

    2013-11-01

    We evaluated the role of dietary iron, heme iron, and supplemental iron on colorectal cancer (CRC) risk in a population-based case-control study in Pennsylvania, including 1005 incident cases and 1062 controls. Diet was assessed through a modified food frequency questionnaire that included supplement use and a meat-specific module. Cases reported intakes for the year before diagnosis, whereas controls reported intakes for the year before interview. Heme iron intake was calculated using a new heme database developed by the US National Cancer Institute. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using unconditional logistic regression. After multivariate adjustment, there were no significant associations between heme iron or total iron intake and CRC incidence. Dietary iron intake was inversely associated with CRC among women (OR Q5 vs. Q1=0.45; 95% CI=0.22-0.92), but not among men. Supplemental iron intake of more than 18 mg/day versus none was positively associated with CRC incidence (OR=2.31; 95% CI=1.48-3.59; P-trendconsumption of more than 18 mg/day of supplemental iron may increase risk for CRC.

  3. Feasibility Study of NMR Based Serum Metabolomic Profiling to Animal Health Monitoring: A Case Study on Iron Storage Disease in Captive Sumatran Rhinoceros (Dicerorhinus sumatrensis).

    Science.gov (United States)

    Watanabe, Miki; Roth, Terri L; Bauer, Stuart J; Lane, Adam; Romick-Rosendale, Lindsey E

    2016-01-01

    A variety of wildlife species maintained in captivity are susceptible to iron storage disease (ISD), or hemochromatosis, a disease resulting from the deposition of excess iron into insoluble iron clusters in soft tissue. Sumatran rhinoceros (Dicerorhinus sumatrensis) is one of the rhinoceros species that has evolutionarily adapted to a low-iron diet and is susceptible to iron overload. Hemosiderosis is reported at necropsy in many African black and Sumatran rhinoceroses but only a small number of animals reportedly die from hemochromatosis. The underlying cause and reasons for differences in susceptibility to hemochromatosis within the taxon remains unclear. Although serum ferritin concentrations have been useful in monitoring the progression of ISD in many species, there is some question regarding their value in diagnosing hemochromatosis in the Sumatran rhino. To investigate the metabolic changes during the development of hemochromatosis and possibly increase our understanding of its progression and individual susceptibility differences, the serum metabolome from a Sumatran rhinoceros was investigated by nuclear magnetic resonance (NMR)-based metabolomics. The study involved samples from female rhinoceros at the Cincinnati Zoo (n = 3), including two animals that died from liver failure caused by ISD, and the Sungai Dusun Rhinoceros Conservation Centre in Peninsular Malaysia (n = 4). Principal component analysis was performed to visually and statistically compare the metabolic profiles of the healthy animals. The results indicated that significant differences were present between the animals at the zoo and the animals in the conservation center. A comparison of the 43 serum metabolomes of three zoo rhinoceros showed two distinct groupings, healthy (n = 30) and unhealthy (n = 13). A total of eighteen altered metabolites were identified in healthy versus unhealthy samples. Results strongly suggest that NMR-based metabolomics is a valuable tool for animal health

  4. Feasibility Study of NMR Based Serum Metabolomic Profiling to Animal Health Monitoring: A Case Study on Iron Storage Disease in Captive Sumatran Rhinoceros (Dicerorhinus sumatrensis.

    Directory of Open Access Journals (Sweden)

    Miki Watanabe

    Full Text Available A variety of wildlife species maintained in captivity are susceptible to iron storage disease (ISD, or hemochromatosis, a disease resulting from the deposition of excess iron into insoluble iron clusters in soft tissue. Sumatran rhinoceros (Dicerorhinus sumatrensis is one of the rhinoceros species that has evolutionarily adapted to a low-iron diet and is susceptible to iron overload. Hemosiderosis is reported at necropsy in many African black and Sumatran rhinoceroses but only a small number of animals reportedly die from hemochromatosis. The underlying cause and reasons for differences in susceptibility to hemochromatosis within the taxon remains unclear. Although serum ferritin concentrations have been useful in monitoring the progression of ISD in many species, there is some question regarding their value in diagnosing hemochromatosis in the Sumatran rhino. To investigate the metabolic changes during the development of hemochromatosis and possibly increase our understanding of its progression and individual susceptibility differences, the serum metabolome from a Sumatran rhinoceros was investigated by nuclear magnetic resonance (NMR-based metabolomics. The study involved samples from female rhinoceros at the Cincinnati Zoo (n = 3, including two animals that died from liver failure caused by ISD, and the Sungai Dusun Rhinoceros Conservation Centre in Peninsular Malaysia (n = 4. Principal component analysis was performed to visually and statistically compare the metabolic profiles of the healthy animals. The results indicated that significant differences were present between the animals at the zoo and the animals in the conservation center. A comparison of the 43 serum metabolomes of three zoo rhinoceros showed two distinct groupings, healthy (n = 30 and unhealthy (n = 13. A total of eighteen altered metabolites were identified in healthy versus unhealthy samples. Results strongly suggest that NMR-based metabolomics is a valuable tool for

  5. Synthesis and in vitro evaluation of bone-seeking superparamagnetic iron oxide nanoparticles as contrast agents for imaging bone metabolic activity.

    Science.gov (United States)

    Panahifar, Arash; Mahmoudi, Morteza; Doschak, Michael R

    2013-06-12

    In this article, we report the synthesis and in vitro evaluation of a new class of nonionizing bone-targeting contrast agents based on bisphosphonate-conjugated superparamagnetic iron oxide nanoparticles (SPIONs), for use in imaging of bone turnover with magnetic resonance imaging (MRI). Similar to bone-targeting (99m)Technetium medronate, our novel contrast agent uses bisphosphonates to impart bone-seeking properties, but replaces the former radioisotope with nonionizing SPIONs which enables their subsequent detection using MRI. Our reported method is relatively simple, quick and cost-effective and results in BP-SPIONs with a final nanoparticle size of 17 nm under electron microscopy technique (i.e., TEM). In-vitro binding studies of our novel bone tracer have shown selective binding affinity (around 65%) for hydroxyapatite, the principal mineral of bone. Bone-targeting SPIONs offer the potential for use as nonionizing MRI contrast agents capable of imaging dynamic bone turnover, for use in the diagnosis and monitoring of metabolic bone diseases and related bone pathology.

  6. Body iron status and gastric cancer risk in the EURGAST study

    NARCIS (Netherlands)

    Fonseca-Nunes, Ana; Agudo, Antonio; Aranda, Núria; Arija, Victoria; Cross, Amanda J.; Molina, Esther; Sanchez, Maria Jose; Bueno-De-Mesquita, H. B.; Siersema, Peter; Weiderpass, Elisabete; Krogh, Vittorio; Mattiello, Amalia; Tumino, Rosario; Saieva, Calogero; Naccarati, Alessio; Ohlsson, Bodil; Sjöberg, Klas; Boutron-Ruault, Marie Christine; Cadeau, Claire; Fagherazzi, Guy; Boeing, Heiner; Steffen, Annika; Kühn, Tilman; Katzke, Verena; Tjønneland, Anne; Olsen, Anja; Khaw, Kay Tee; Wareham, Nick; Key, Tim; Lu, Yunxia; Riboli, Elio; Peeters, Petra H.; Gavrila, Diana; Dorronsoro, Miren; Quirõs, José Ramõn; Barricarte, Aurelio; Jenab, Mazda; Zamora-Ros, Raúl; Freisling, Heinz; Trichopoulou, Antonia; Lagiou, Pagona; Bamia, Christina; Jakszyn, Paula

    2015-01-01

    Although it appears biologically plausible for iron to be associated with gastric carcinogenesis, the evidence is insufficient to lead to any conclusions. To further investigate the relationship between body iron status and gastric cancer risk, we conducted a nested case-control study in the

  7. Longitudinal study on osteoarthritis and bone metabolism

    Directory of Open Access Journals (Sweden)

    L. Postiglione

    2011-09-01

    Full Text Available Objective: The relationship between Osteoarthritis (OA and Osteoporosis (OP is not well defined due to lacking in longitudinal data, mainly regarding correlations between biochemical factors and OA incidence. Aim of this paper was to investigate the predictive value for OA incidence of bone mass variations and of selected biochemical markers in healthy women participating in a population-based longitudinal study carried out in Naples (Italy. Subjects and Methods: High completion rate (85.2% and statistically adequate sample size were obtained: 139 women (45 to 79 years of age were examined and follow up visit was performed after two years (24±2 months, following the same protocol. Patients underwent medical examination, questionnaire, anthropometric measurements, blood sampling and urine collection. Bone mineral density (BMD measurement was performed by dual energy X-ray absorptiometry (DEXA at the lumbar spine (L1-L4 and femoral neck. Radiographs of dorsal and lumbar spine in lateral view were performed at basal and at 24 months visits; a team of three experts scored radiographs using Kellegren and Lawrence grading. Results: The score was calculated for two individual radiographic features (narrowing of the joint space, presence of osteophytes and as a global score. Results show a relevant percentage, 23% up, of subjects presenting both OA and OP. In the cross-sectional study the presence of osteophytosis correlates with anthropometric variables and PTH levels. In the longitudinal study results show a correlation between serum vitamin D and delta score for osteophytosis (β=0.02 p<0.05. Conclusions: Data obtained outline the importance of further studies on the pathogenetic link between OA and bone metabolism.

  8. Transmission electron microscope study of fusion-environment radiation damage in iron and iron-chromium alloys

    Energy Technology Data Exchange (ETDEWEB)

    Horton, L.L.S.

    1982-07-01

    A transmission electron microscopy study of radiation damage microstructures in iron and iron-chromium alloys has been performed. This study consisted of both qualitative and quantitative characterization of the dislocation and cavity microstructures, including determination of vacancy/interstitial character and Burgers vectors for dislocation loops and analysis of the cavity morphology. The effects of irradiation temperature, fluence, helium implantation, and chromium content were investigated. Neutron irradiation (iron specimens, 1 dpa, 455 to 1000 K) and triple-beam ion irradiation (Fe-10% Cr specimens, 10 dpa, 725 to 950 K; Fe-10% Cr specimens, 850 K, 0.3 to 100 dpa; and Fe, Fe-5% Cr, Fe-10% Cr specimens, 850 K, 10 dpa) were employed. In the triple-beam ion irradiation procedure, simultaneous bombardment with 4 MeV Fe/sup + +/ ions and energetic He/sup +/ and D/sub 2//sup +/ ions was used to simulate the fusion environment (10 at. ppM He/dpa and 41 at. ppM D/dpa). In addition, single-beam 4 MeV Fe/sup + +/ ion irradiations of Fe-10% Cr both with and without pre-injection of helium and deuterium were performed.

  9. Transmission electron microscope study of fusion-environment radiation damage in iron and iron-chromium alloys

    International Nuclear Information System (INIS)

    Horton, L.L.S.

    1982-07-01

    A transmission electron microscopy study of radiation damage microstructures in iron and iron-chromium alloys has been performed. This study consisted of both qualitative and quantitative characterization of the dislocation and cavity microstructures, including determination of vacancy/interstitial character and Burgers vectors for dislocation loops and analysis of the cavity morphology. The effects of irradiation temperature, fluence, helium implantation, and chromium content were investigated. Neutron irradiation (iron specimens, 1 dpa, 455 to 1000 K) and triple-beam ion irradiation (Fe-10% Cr specimens, 10 dpa, 725 to 950 K; Fe-10% Cr specimens, 850 K, 0.3 to 100 dpa; and Fe, Fe-5% Cr, Fe-10% Cr specimens, 850 K, 10 dpa) were employed. In the triple-beam ion irradiation procedure, simultaneous bombardment with 4 MeV Fe ++ ions and energetic He + and D 2 + ions was used to simulate the fusion environment (10 at. ppM He/dpa and 41 at. ppM D/dpa). In addition, single-beam 4 MeV Fe ++ ion irradiations of Fe-10% Cr both with and without pre-injection of helium and deuterium were performed

  10. Influence of food tannins on certain aspects of iron metabolism : Part 2 -- Storage and transport in normal and anemic rats

    Energy Technology Data Exchange (ETDEWEB)

    Roy, S N [Albert Einstein Coll. of Medicine, Bronx, NY (USA); Mukherjee, S [Calcutta Univ. (India). Dept. of Applied Chemistry

    1979-04-01

    Administration of tannin (0.5 mg/kg body wt/day) from fruits and vegetables lowers the iron content in liver, spleen and bone marrow with an elevation in Total Iron Binding Capacity (TIBC) of serum and serum iron concentration in normal rats. The same dose of tannin increases the iron content in storage tissues, particularly bone marrow of hemolytic anemic rats. In anemic rats, TIBC is decreased and serum iron concentration is raised from anemic level to approximately normal value due to ingestion of tannin. Radioiron administration, either by oral or by intravenous route, also elicits similar results. Recovery of iron storage and transport values from the anemic to the normal condition by tannin (0.5 mg/kg) varies with the source of tannin used. Thus more iron required for compensating the anemic conditions is retained within their body by tannin (0.5 mg/kg) which appears to reduce the loss of peripheral iron probably by protecting the lysis of red cells.

  11. XPS and FTIR spectroscopic study on microwave treated high phosphorus iron ore

    International Nuclear Information System (INIS)

    Omran, Mamdouh; Fabritius, Timo; Elmahdy, Ahmed M.; Abdel-Khalek, Nagui A.; El-Aref, Mortada; Elmanawi, Abd El-Hamid

    2015-01-01

    Highlights: • The effect of microwave radiation on structure and chemical state of high phosphorus iron ore was studied. • FTIR analyses showed that after microwave radiation the functional chemical groups of phosphorus bearing minerals (fluorapatite) dissociated. • High resolution XPS analyses of Fe 2p peaks showed that after microwave radiation a portion of Fe(+III) was reduced to Fe(+II). • Microwave radiation had a positive effect on the magnetic properties of iron oxide, through formation of ferromagnetic phases. - Abstract: A growing interest in microwave heating has emerged recently. Several potential microwave applications regarding minerals’ processing have been investigated. This paper investigates the effect of microwave radiation on Egyptian high phosphorus iron ore. Three different iron ore samples have varying Fe 2 O 3 and P 2 O 5 contents and mineralogical textures were studied. A comparative study has been carried out between untreated and microwave treated iron ore. XRD and FTIR analyses showed that after microwave radiation the crystallinity of iron bearing minerals (hematite) increased, while the functional chemical groups of phosphorus bearing minerals (fluorapatite) and other gangues dissociated. High resolution XPS analyses of Fe 2p peaks showed that after microwave radiation a portion of Fe(+III) was reduced to Fe(+II). This means that after microwave radiation iron oxide (hematite, Fe 3+ ) transformed into more magnetic phase. The results indicated that microwave radiation had a positive effect on the magnetic properties of iron oxide, through formation of ferromagnetic phases

  12. The contribution of diet and genotype to iron status in women: a classical twin study.

    Science.gov (United States)

    Fairweather-Tait, Susan J; Guile, Geoffrey R; Valdes, Ana M; Wawer, Anna A; Hurst, Rachel; Skinner, Jane; Macgregor, Alexander J

    2013-01-01

    This is the first published report examining the combined effect of diet and genotype on body iron content using a classical twin study design. The aim of this study was to determine the relative contribution of genetic and environmental factors in determining iron status. The population was comprised of 200 BMI- and age-matched pairs of MZ and DZ healthy twins, characterised for habitual diet and 15 iron-related candidate genetic markers. Variance components analysis demonstrated that the heritability of serum ferritin (SF) and soluble transferrin receptor was 44% and 54% respectively. Measured single nucleotide polymorphisms explained 5% and selected dietary factors 6% of the variance in iron status; there was a negative association between calcium intake and body iron (p = 0.02) and SF (p = 0.04).

  13. Isotope aided studies of the bioavailability of iron from human diets consumed in Peru

    International Nuclear Information System (INIS)

    Zavaleta, N.; Penny, M.; Berlanga, R.; Diaz, A.; Montoya, E.; Lonnerdal, B.

    1994-01-01

    Iron deficiency anaemia is an important health problem in Peru, which affects approximately 25% of the population. The most vulnerable groups are children below 5 years of age and pregnant women, of whom 64% and 53% respectively are anemic. The main reason for this deficiency is inadequate iron intake. Heme iron consumption is very low, and non-heme iron is virtually the only source of iron in the diet. Despite regional differences in food consumption, wheat, salt and sugar are widely consumed in all areas. Wheat is likely to be the most suitable food vehicle for iron fortification due to the processing required. Based on the recent food consumption surveys conducted in Lima by the IIN, we selected examples of typical main meals and measured iron bioavailability in the diet using an extrinsic tag method with 1.5 μCi of 59 Fe and 5 μCi of 55 Fe as markers. Coffee with bread and butter for breakfast, noodle soup with vegetables, rice with seasoned tripe (cow), bread and lemonade for lunch; and noodle soup with vegetables and bread for dinner were used to measure iron absorption. Thirteen adults in apparent good health, 5 male and 8 female, with normal hemoglobin levels participated in the study. The mean iron absorption from breakfast was 4.2% ± 4.1; from lunch 14.65% ± 10/95, and from dinner 5.1% ± 2.84. The presence of heme iron from tripe and ascorbic acid from lemonade improved iron absorption. (author). 17 refs, 3 tabs

  14. Moessbauer spectroscopic studies of alkylammonium iron(III) complexes

    International Nuclear Information System (INIS)

    Katada, M.; Kozawa, S.; Nakajima, Y.

    2006-01-01

    Alkylammonium iron(III) complexes, [(n-C n H 2n+1 )mNH 4-m ] 3 [Fe(CN) 6 ] were prepared and studied by Moessbauer spectroscopy, XRD, and DSC. In the complexes with m=2, the temperature dependences of the area intensity of Moessbauer are correlated to the motion of alkyl chains. The temperature dependence of the complex with n=4 was linear and smaller than that of other complexes. Especially in the complex with n=6, the deviation from the linear was the largest in the complexes observed. This result is attributed to the structural difference of the complex. The complexes with n≥8 consist of two-dimensional layer structure. The temperature dependence of the area intensity was similar to each other. This means that the motion of alkyl chain in these complexes are almost the same. The values of quadrupole splitting for the complexes were larger those that of the complexes (m=1). This indicates that the form of [Fe(CN) 6 ] 3- ion is affected by the differences of the number of alkyl groups. (author)

  15. Theoretical study of impurity effects in iron-based superconductors

    Science.gov (United States)

    Navarro Gastiasoro, Maria; Hirschfeld, Peter; Andersen, Brian

    2013-03-01

    Several open questions remain unanswered for the iron-based superconductors (FeSC), including the importance of electronic correlations and the symmetry of the superconducting order parameter. Motivated by recent STM experiments which show a fascinating variety of resonant defect states in FeSC, we adopt a realistic five-band model including electronic Coulomb correlations to study local effects of disorder in the FeSC. In order to minimize the number of free parameters, we use the pairing interactions obtained from spin-fluctuation exchange to determine the homogeneous superconducting state. The ability of local impurity potentials to induce resonant states depends on their scattering strength Vimp; in addition, for appropriate Vimp, such states are associated with local orbital- and magnetic order. We investigate the density of states near such impurities and show how tunneling experiments may be used to probe local induced order. In the SDW phase, we show how C2 symmetry-breaking dimers are naturally formed around impurities which also form cigar-like (pi,pi) structures embedded in the (pi,0) magnetic bulk phase. Such electronic dimers have been shown to be candidates for explaining the so-called nematogens observed previously by QPI in Co-doped CaFe2As2.

  16. Evaluation of tumoral enhancement by superparamagnetic iron oxide particles: comparative studies with ferumoxtran and anionic iron oxide nanoparticles

    International Nuclear Information System (INIS)

    Brillet, P-Y.; Gazeau, F.; Luciani, A.; Bessoud, B.; Cuenod, C.-A.; Siauve, N.; Pons, J.-N.; Poupon, J.; Clement, O.

    2005-01-01

    This study was designed to compare tumor enhancement by superparamagnetic iron oxide particles, using anionic iron oxide nanoparticles (AP) and ferumoxtran. In vitro, relaxometry and media with increasing complexity were used to assess the changes in r2 relaxivity due to cellular internalization. In vivo, 26 mice with subcutaneously implanted tumors were imaged for 24 h after injection of particles to describe kinetics of enhancement using T1 spin echo, T2 spin echo, and T2 fast spin echo sequences. In vitro, the r2 relaxivity decreased over time (0-4 h) when AP were uptaken by cells. The loss of r2 relaxivity was less pronounced with long (Hahn Echo) than short (Carr-Purcell-Meiboom-Gill) echo time sequences. In vivo, our results with ferumoxtran showed an early T2 peak (1 h), suggesting intravascular particles and a second peak in T1 (12 h), suggesting intrainterstitial accumulation of particles. With AP, the late peak (24 h) suggested an intracellular accumulation of particles. In vitro, anionic iron oxide nanoparticles are suitable for cellular labeling due to a high cellular uptake. Conversely, in vivo, ferumoxtran is suitable for passive targeting of tumors due to a favorable biodistribution. (orig.)

  17. Analysis of the global ocean sampling (GOS) project for trends in iron uptake by surface ocean microbes.

    Science.gov (United States)

    Toulza, Eve; Tagliabue, Alessandro; Blain, Stéphane; Piganeau, Gwenael

    2012-01-01

    Microbial metagenomes are DNA samples of the most abundant, and therefore most successful organisms at the sampling time and location for a given cell size range. The study of microbial communities via their DNA content has revolutionized our understanding of microbial ecology and evolution. Iron availability is a critical resource that limits microbial communities' growth in many oceanic areas. Here, we built a database of 2319 sequences, corresponding to 140 gene families of iron metabolism with a large phylogenetic spread, to explore the microbial strategies of iron acquisition in the ocean's bacterial community. We estimate iron metabolism strategies from metagenome gene content and investigate whether their prevalence varies with dissolved iron concentrations obtained from a biogeochemical model. We show significant quantitative and qualitative variations in iron metabolism pathways, with a higher proportion of iron metabolism genes in low iron environments. We found a striking difference between coastal and open ocean sites regarding Fe(2+) versus Fe(3+) uptake gene prevalence. We also show that non-specific siderophore uptake increases in low iron open ocean environments, suggesting bacteria may acquire iron from natural siderophore-like organic complexes. Despite the lack of knowledge of iron uptake mechanisms in most marine microorganisms, our approach provides insights into how the iron metabolic pathways of microbial communities may vary with seawater iron concentrations.

  18. Mild iron overload in patients carrying the HFE S65C gene mutation: a retrospective study in patients with suspected iron overload and healthy controls

    OpenAIRE

    Holmström, P; Marmur, J; Eggertsen, G; Gåfvels, M; Stål, P

    2002-01-01

    Background and aims: The role of the HFE S65C mutation in the development of hepatic iron overload is unknown. The aim of the present study was: (A) to determine the HFE S65C frequency in a Northern European population; and (B) to evaluate whether the presence of the HFE S65C mutation would result in a significant hepatic iron overload.

  19. In vitro metabolism and permeation studies in rat jejunum

    DEFF Research Database (Denmark)

    Gammelgaard, Bente; Jensen, K; Steffansen, B

    1999-01-01

    The purpose of these studies was to compare the in vitro absorption of two inorganic chromium(III) compounds: chromium chloride and chromium nitrate, with organic chromium(III)-picolinate; and to investigate if any in vitro metabolism of chromium(VI) takes place. The in vitro metabolism studies...

  20. Iron bioavailability studies as assessed by intrinsic and extrinsic labeling techniques

    International Nuclear Information System (INIS)

    Johnson, C.D.

    1985-01-01

    Although soybeans are a rich source of iron and incorporation of soy protein into diets is increasing, the presence of phytate or fiber endogenous to the seeds may inhibit total iron absorption from diets including soy protein. Four studies on iron bioavailability as assessed by intrinsic and extrinsic labeling techniques in rats were completed. The effect of previous dietary protein on the absorption of intrinsically 59 Fe labeled defatted soy flour was determined in rats. The results indicated that the type of dietary protein (animal vs. plant) in pre-test diets would have little influence on iron absorption from a single soy protein test meal. Therefore, adaptation of soy protein does not improve bioavailability of iron. Soybean hulls were investigated as a source of iron fortification in bread. The results indicated that retention of 59 Fe from white bread baked with soy hulls did not differ from white bread fortified with bakery grade ferrous sulfate. The effect of endogenous soybean phytate on iron absorption in rats was measured using seeds of varying phytate content and intrinsically labeled with 59 Fe. Increasing concentration of phytate in whole soybean flour had no significant effect on iron absorption

  1. X-ray absorption spectroscopic studies of mononuclear non-heme iron enzymes

    Energy Technology Data Exchange (ETDEWEB)

    Westre, Tami E. [Stanford Univ., CA (United States)

    1996-01-01

    Fe-K-edge X-ray absorption spectroscopy (XAS) has been used to investigate the electronic and geometric structure of the iron active site in non-heme iron enzymes. A new theoretical extended X-ray absorption fine structure (EXAFS) analysis approach, called GNXAS, has been tested on data for iron model complexes to evaluate the utility and reliability of this new technique, especially with respect to the effects of multiple-scattering. In addition, a detailed analysis of the 1s→3d pre-edge feature has been developed as a tool for investigating the oxidation state, spin state, and geometry of iron sites. Edge and EXAFS analyses have then been applied to the study of non-heme iron enzyme active sites.

  2. Moessbauer study on the distribution of iron vacancies in iron sulfide Fe sub(1-x)S

    International Nuclear Information System (INIS)

    Igaki, Kenzo; Sato, Masaki; Shinohara, Takeshi.

    1982-01-01

    The distribution of iron vacancies in iron sulfide Fe sub(1-x)S with the controlled compositions was investigated by Moessbauer spectroscopy at room temperature. Moessbauer spectrum was composed of several component spectra. These component spectra were assigned to the iron atoms with different configurations of neighboring iron vacancies. Judging from the composition dependence of intensity of each component, iron vacancies are considered to lie in every second iron layer for specimens with x between 0.125 and 0.10. For specimens with x between 0.10 and 0.09, this arrangement is nearly kept in the sample quenched from a higher temperature than 473 K, but after annealing at a lower temperature than 473 K iron vacancies are considered to lie not only in every second iron layer but also in every third iron layer or in adjacent iron layers. The iron vacancy arrangement lying in every third iron layer or in adjacent iron layers tends to dominate for specimens with x below 0.09. (author)

  3. Regulatory mechanisms for iron transport across the blood-brain barrier.

    Science.gov (United States)

    Duck, Kari A; Simpson, Ian A; Connor, James R

    2017-12-09

    Many critical metabolic functions in the brain require adequate and timely delivery of iron. However, most studies when considering brain iron uptake have ignored the iron requirements of the endothelial cells that form the blood-brain barrier (BBB). Moreover, current models of BBB iron transport do not address regional regulation of brain iron uptake or how neurons, when adapting to metabolic demands, can acquire more iron. In this study, we demonstrate that both iron-poor transferrin (apo-Tf) and the iron chelator, deferoxamine, stimulate release of iron from iron-loaded endothelial cells in an in vitro BBB model. The role of the endosomal divalent metal transporter 1 (DMT1) in BBB iron acquisition and transport has been questioned. Here, we show that inhibition of DMT1 alters the transport of iron and Tf across the endothelial cells. These data support an endosome-mediated model of Tf-bound iron uptake into the brain and identifies mechanisms for local regional regulation of brain iron uptake. Moreover, our data provide an explanation for the disparity in the ratio of Tf to iron transport into the brain that has confounded the field. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Modelling iron mismanagement in neurodegenerative disease in vitro: paradigms, pitfalls, possibilities & practical considerations.

    Science.gov (United States)

    Healy, Sinead; McMahon, Jill M; FitzGerald, Una

    2017-11-01

    Although aberrant metabolism and deposition of iron has been associated with aging and neurodegeneration, the contribution of iron to neuropathology is unclear. Well-designed model systems that are suited to studying the putative pathological effect of iron are likely to be essential if such unresolved details are to be clarified. In this review, we have evaluated the utility and effectiveness of the reductionist in vitro platform to study the molecular mechanisms putatively underlying iron perturbations of neurodegenerative disease. The expression and function of iron metabolism proteins in glia and neurons and the extent to which this iron regulatory system is replicated in in vitro models has been comprehensively described, followed by an appraisal of the inherent suitability of different in vitro and ex vivo models that have been, or might be, used for iron loading. Next, we have identified and critiqued the relevant experimental parameters that have been used in in vitro iron loading experiments, including the choice of iron reagent, relevant iron loading concentrations and supplementation with serum or ascorbate, and propose optimal iron loading conditions. Finally, we have provided a synthesis of the differential iron accumulation and toxicity in glia and neurons from reported iron loading paradigms. In summary, this review has amalgamated the findings and paradigms of the published reports modelling iron loading in monocultures, discussed the limitations and discrepancies of such work to critically propose a robust, relevant and reliable model of iron loading to be used for future investigations. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Study of iron-zinc catalysts by Moessbauer spectroscopy

    International Nuclear Information System (INIS)

    Arriola, S.H.

    1990-01-01

    The Moessbauer parameters were determined on a series of catalyst mixtures of iron and zinc oxides with variable quantities of zinc. A change in the crystal structure of the iron oxide when introducing zinc into the samples was observed. The corundum structure of the α-Fe 2 O 3 phase was transformed into the spinel type of zinc ferrite when zinc oxide was present in any quantity. A strong electronic interaction between the zinc ferrite and the zinc oxide present in excess was evident. The catalysts were analyzed using x-ray fluorescence and x-ray diffraction methods. (author) 10 refs.; 4 figs.; 2 tabs

  6. A STUDY OF IRON AND STEEL SECTOR IN INDIA

    OpenAIRE

    Chand, Sumit

    2008-01-01

    ABSTRACT The iron and steel manufacturing sector is one of the largest sectors in the world in terms of financial volume of trade, employment potential, development of ancillary and allied industries and geographical spread. Added to this is the fact that iron and steel is used as an input in almost all the industrial and manufacturing sectors and goods produced by them. As a result this sector attracts the maximum attention of almost all the countries of the world, whether being one of t...

  7. Study of nanodispersed aluminum and iron alcosols by photoacoustic spectroscopy

    Science.gov (United States)

    An, Vladimir; de Izarra, Charles; Saveliev, Gennady

    2011-06-01

    Nanodispersed aluminum and iron alcosols were prepared by ultrasonic dispersion of nanodispersed aluminum and iron powders in absolute ethanol. The photoacoustic signal (PAS) produced in modulated CO2 laser irradiation (1.026 and 1.096 kHz) of alcosols depends on the nature and method of nanoparticle fabrication and does not depend on their concentration in ethanol (within 1-5 g/l). Chemical interaction between metal nanoparticles and ethanol activated by laser irradiation or/and ultrasound is considered as the cause of the PAS.

  8. Deciphering the iron isotope message of the human body

    Science.gov (United States)

    Walczyk, Thomas; von Blanckenburg, Friedhelm

    2005-04-01

    Mass-dependent variations in isotopic composition are known since decades for the light elements such as hydrogen, carbon or oxygen. Multicollector-inductively coupled plasma mass spectrometry (MC-ICP-MS) and double-spike thermal ionization mass spectrometry (TIMS) permit us now to resolve small variations in isotopic composition even for the heavier elements such as iron. Recent studies on the iron isotopic composition of human blood and dietary iron sources have shown that lighter iron isotopes are enriched along the food chain and that each individual bears a certain iron isotopic signature in blood. To make use of this finding in biomedical research, underlying mechanisms of isotope fractionation by the human body need to be understood. In this paper available iron isotope data for biological samples are discussed within the context of isotope fractionation concepts and fundamental aspects of human iron metabolism. This includes evaluation of new data for body tissues which show that blood and muscle tissue have a similar iron isotopic composition while heavier iron isotopes are concentrated in the liver. This new observation is in agreement with our earlier hypothesis of a preferential absorption of lighter iron isotopes by the human body. Possible mechanisms for inducing an iron isotope effect at the cellular and molecular level during iron uptake are presented and the potential of iron isotope effects in human blood as a long-term measure of dietary iron absorption is discussed.

  9. Microbial Community Composition Impacts Pathogen Iron Availability during Polymicrobial Infection.

    Directory of Open Access Journals (Sweden)

    Apollo Stacy

    2016-12-01

    Full Text Available Iron is an essential nutrient for bacterial pathogenesis, but in the host, iron is tightly sequestered, limiting its availability for bacterial growth. Although this is an important arm of host immunity, most studies examine how bacteria respond to iron restriction in laboratory rather than host settings, where the microbiome can potentially alter pathogen strategies for acquiring iron. One of the most important transcriptional regulators controlling bacterial iron homeostasis is Fur. Here we used a combination of RNA-seq and chromatin immunoprecipitation (ChIP-seq to characterize the iron-restricted and Fur regulons of the biofilm-forming opportunistic pathogen Aggregatibacter actinomycetemcomitans. We discovered that iron restriction and Fur regulate 4% and 3.5% of the genome, respectively. While most genes in these regulons were related to iron uptake and metabolism, we found that Fur also directly regulates the biofilm-dispersing enzyme Dispersin B, allowing A. actinomycetemcomitans to escape from iron-scarce environments. We then leveraged these datasets to assess the availability of iron to A. actinomycetemcomitans in its primary infection sites, abscesses and the oral cavity. We found that A. actinomycetemcomitans is not restricted for iron in a murine abscess mono-infection, but becomes restricted for iron upon co-infection with the oral commensal Streptococcus gordonii. Furthermore, in the transition from health to disease in human gum infection, A. actinomycetemcomitans also becomes restricted for iron. These results suggest that host iron availability is heterogeneous and dependent on the infecting bacterial community.

  10. inflammation and iron metabolism

    Directory of Open Access Journals (Sweden)

    A Dzedzej

    2016-08-01

    Full Text Available Following acute physical activity, blood hepcidin concentration appears to increase in response to exercise-induced inflammation, but the long-term impact of exercise on hepcidin remains unclear. Here we investigated changes in hepcidin and the inflammation marker interleukin-6 to evaluate professional basketball players’ response to a season of training and games. The analysis also included vitamin D (25(OHD3 assessment, owing to its anti-inflammatory effects. Blood samples were collected for 14 players and 10 control non-athletes prior to and after the 8-month competitive season. Athletes’ performance was assessed with the NBA efficiency score. At the baseline hepcidin correlated with blood ferritin (r=0.61; 90% CL ±0.31, but at the end of the season this correlation was absent. Compared with the control subjects, athletes experienced clear large increases in hepcidin (50%; 90% CI 15-96% and interleukin-6 (77%; 90% CI 35-131% and a clear small decrease in vitamin D (-12%; 90% CI -20 to -3% at the season completion. Correlations between change scores of these variables were unclear (r = -0.21 to 0.24, 90% CL ±0.5, but their uncertainty generally excluded strong relationships. Athletes were hence concluded to have experienced acute inflammation at the beginning but chronic inflammation at the end of the competitive season. At the same time, the moderate correlation between changes in vitamin D and players’ performance (r=0.43 was suggestive of its beneficial influence. Maintaining the appropriative concentration of vitamin D is thus necessary for basketball players’ performance and efficiency. The assessment of hepcidin has proven to be useful in diagnosing inflammation in response to chronic exercise.

  11. Protocols to Study Growth and Metabolism in Drosophila.

    Science.gov (United States)

    Strassburger, Katrin; Teleman, Aurelio A

    2016-01-01

    Signaling pathways such as the insulin/insulin-like growth factor pathway concurrently regulate organismal growth and metabolism. Drosophila has become a popular model system for studying both organismal growth and metabolic regulation. Care must be taken, however, when assessing such phenotypes because they are quantitative in nature, and influenced by environment. This chapter first describes how to control animal age and nutrient availability, since growth and metabolism are sensitive to these parameters. It then provides protocols for measuring tissue growth, cell size, and metabolic parameters such as stored lipids and glycogen, and circulating sugars.

  12. Metabolism

    Science.gov (United States)

    ... lin), which signals cells to increase their anabolic activities. Metabolism is a complicated chemical process, so it's not ... how those enzymes or hormones work. When the metabolism of body chemicals is ... Hyperthyroidism (pronounced: hi-per-THIGH-roy-dih-zum). Hyperthyroidism ...

  13. Studying antioxidant, radioprotective and antibacterial actions of iron complexes

    International Nuclear Information System (INIS)

    Shamilov, E.N.

    2006-01-01

    Full Text: It was investigated regulation of the malone dialdehyde consent ration in the action of the chemical agents and radiation on the white rats liver tissue at participation of dittsiklopenthadienil-Fe and Fe-ru tinate, and it was also investigated the biological activity of some complexes of iron on some Gram positive bacteria strains of the genius of Basillus

  14. Textural and morphological studies on zinc-iron alloy electrodeposits

    Indian Academy of Sciences (India)

    Zinc-iron alloy electrodeposits have industrial significance, since they provide better corrosion resistance and with improved mechanical properties when compared to pure zinc coatings. This is due to the unique phase structure of the alloy formed. But this deposition belongs to anomalous deposition, where the ...

  15. ICARUS-4 : sector study for the iron and steel industry

    NARCIS (Netherlands)

    Michels, K.

    2000-01-01

    In this report we describe the energy consumption in 1995 and the energy saving options that exist within the iron and steel manufacturing industry (SBI/NACE 27.1-3) in the Netherlands. The data will be included in the ICARUS-4 database which gives an inventory of the technological options for

  16. A study of DLC coatings for ironing of stainless steel

    DEFF Research Database (Denmark)

    Sulaiman, Mohd Hafis Bin; Christiansen, Peter; Bay, Niels Oluf

    2017-01-01

    severe lubrication conditions by adopting strip reduction testing to replicate industrial ironing production of deep drawn, stainless steel cans. Three DLC coatings are investigated; multi-layer, double layer and single layer. Experiments revealed that the double layer coating worked successful, i...

  17. Toxicological studies and antimicrobial properties of some Iron(III ...

    African Journals Online (AJOL)

    SERVER

    2007-12-17

    Dec 17, 2007 ... Two iron(III) complexes of Ciprofloxacin were synthesized by reaction of the ... The infrared spectra suggest that two classes of compounds were obtained: molecular complex in .... Soluble in H2O, MeOH, EtOH; Mol. cond.

  18. Pilot study points way to iron/manganese removal

    Energy Technology Data Exchange (ETDEWEB)

    Qureshi, N.; Barnes, A. [Progressive Consulting Engineers Inc., Minneapolis, MN (United States)

    1994-12-31

    The use of coal, greensand and sand in filters for removing iron and manganese from the Brooklyn Park, Minnesota, water supply was investigated. The most effective and economic treatment involved using a dual media filtration and potassium permanganate as the oxidant.

  19. Mössbauer study of some biological iron complexes

    Indian Academy of Sciences (India)

    Abstract. Some biological complexes containing iron are investigated experimentally at room temperature using the Mössbauer resonance. The complexes show quadrupole doublet and Kramer's degeneracy is found to exist. The electric field gradient, difference in s-electron densities and quadrupole coupling constant ...

  20. Animal metabolism

    International Nuclear Information System (INIS)

    Walburg, H.E.

    1977-01-01

    Studies on placental transport included the following: clearance of tritiated water as a baseline measurement for transport of materials across perfused placentas; transport of organic and inorganic mercury across the perfused placenta of the guinea pig in late gestation; and transport of cadmium across the perfused placenta of the guinea pig in late gestation. Studies on cadmium absorption and metabolism included the following: intestinal absorption and retention of cadmium in neonatal rats; uptake and distribution of an oral dose of cadmium in postweanling male and female, iron-deficient and normal rats; postnatal viability and growth in rat pups after oral cadmium administration during gestation; and the effect of calcium and phosphorus on the absorption and toxicity of cadmium. Studies on gastrointestinal absorption and mineral metabolism included: uptake and distribution of orally administered plutonium complex compounds in male mice; gastrointestinal absorption of 144 Ce in the newborn mouse, rat, and pig; and gastrointestinal absorption of 95 Nb by rats of different ages. Studies on iodine metabolism included the following: influence of thyroid status and thiocyanate on iodine metabolism in the bovine; effects of simulated fallout radiation on iodine metabolism in dairy cattle; and effects of feeding iodine binding agents on iodine metabolism in the calf

  1. Thermal expansion and magnetostriction studies on iron pnictides

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Liran

    2010-09-19

    In this work, a 3-terminal capacitance dilatometer was set up and used for measurements of the thermal expansion and magnetostriction of novel superconducting iron pinictides and related materials. In particular, RFeAsO with R = La, Ce, Pr, Sm, Gd, LaFeASO{sub 1-x}F{sub x} and Ca(F{sub 1-c}Co{sub x}){sub 2}As{sub 2} have been investigated. The data on polycrystalline LaFeAsO{sub 1-x} are the first published thermal expansion data on this material. The lattice effects at the structural and the magnetic phase transition have been investigated and the phase diagram upon F-doping has been studied. A main result is the observation of a previously unknown fluctuation regime for the doping level x ≤ 0.04 over a large T range above the structural transition temperature T{sub S}. The absence of any structural anomalies in the normal state of the superconducting LaFeAlO{sub 1-x}F{sub x} samples with x ≥ 0.05 corroborates the discontinuous character of the phase boundary not only for the magnetism but also for the structural degrees of freedom. Similarly, the presence of high-temperature fluctuations is found for all RFeAsO undoped materials under study. The discussion of the probable origin of the fluctuations as well as the definition of the structural transition temperature T{sub S} are done. The low temperature features shown by the thermal expansion data for RFeAsO are caused by the onset of long range magnetic order of the 4f-moments and their different configurations. In particular, PrFeAsO, which has a very pronounced anomaly associated with Pr-ordering exhibits a large magnetostriction at low temperatures. By discussing this effect along with the magnetization, resistivity and other measurements, it is found that this large magneto-elastic effect may originate from the correlations between the momentum from Fe{sup 3+} and Pr{sup 3+}. Last, the thermal expansion of Ca(Fe{sub 1-x}Co{sub x}){sub 2}As{sub 2} 122 single crystals is investigated. Ca(Fe{sub 1-x}Co{sub x

  2. Ultrasonic-assisted synthesis and magnetic studies of iron oxide/MCM-41 nanocomposite

    International Nuclear Information System (INIS)

    Ursachi, Irina; Vasile, Aurelia; Ianculescu, Adelina; Vasile, Eugeniu; Stancu, Alexandru

    2011-01-01

    Highlights: → A quick and facile route for the synthesis of iron oxide/MCM-41 nanocomposite. → Magnetic nanoparticles were stabilized inside the pores of mesoporous silica MCM-41. → The pore size of MCM-41 dictates the properties of iron oxide nanoparticles. → The procedure provides a narrow size distribution of magnetic nanoparticles. - Abstract: Iron oxide nanoparticles were stabilized within the pores of mesoporous silica MCM-41 amino-functionalized by a sonochemical method. Formation of iron oxide nanoparticles inside the mesoporous channels of amino-functionalized MCM-41 was realized by wet impregnation using iron nitrate, followed by calcinations at 550 deg. C in air. The effect of functionalization level on structural and magnetic properties of obtained nanocomposites was studied. The resulting materials were characterized by powder X-ray diffraction (XRD), high-resolution transmission electron microscopy and selected area electron diffraction (HRTEM and SAED), vibrating sample and superconducting quantum interface magnetometers (VSM and SQUID) and nitrogen adsorption-desorption isotherms measurements. The HRTEM images reveal that the most of the iron oxide nanoparticles were dispersed inside the mesopores of silica matrix and the pore diameter of the amino-functionalized MCM-41 matrix dictates the particle size of iron oxide nanoparticles. The obtained material possesses mesoporous structure and interesting magnetic properties. Saturation magnetization value of magnetic iron oxide nanopatricles stabilized in MCM-41 amino-functionalized by in situ sonochemical synthesis was 1.84 emu g -1 . An important finding is that obtained magnetic nanocomposite materials exhibit enhanced magnetic properties than those of iron oxide/MCM-41 nanocomposite obtained by conventional method. The described method is providing a rather short preparation time and a narrow size distribution of iron oxide nanoparticles.

  3. Low iron stores are related to higher blood concentrations of manganese, cobalt and cadmium in non-smoking, Norwegian women in the HUNT 2 study

    International Nuclear Information System (INIS)

    Margrete Meltzer, Helle; Lise Brantsaeter, Anne; Borch-Iohnsen, Berit; Ellingsen, Dag G.; Alexander, Jan; Thomassen, Yngvar; Stigum, Hein; Ydersbond, Trond A.

    2010-01-01

    Low iron (Fe) stores may influence absorption or transport of divalent metals in blood. To obtain more knowledge about such associations, the divalent metal ions cadmium (Cd), manganese (Mn), cobalt (Co), copper (Cu), zinc (Zn) and lead (Pb) and parameters of Fe metabolism (serum ferritin, haemoglobin (Hb) and transferrin) were investigated in 448 healthy, menstruating non-smoking women, age 20-55 years (mean 38 years), participating in the Norwegian HUNT 2 study. The study population was stratified for serum ferritin: 257 were iron-depleted (serum ferritin 2 for the models were 0.28, 0.48 and 0.34, respectively. Strong positive associations between blood concentrations of Mn, Co and Cd were observed, also when controlled for their common association with ferritin. Apart from these associations, the models showed no significant interactions between the six divalent metals studied. Very mild anaemia (110≤Hb<120 g/L) did not seem to have any effect independent of low ferritin. Approximately 26% of the women with iron deficiency anaemia had high concentrations of all of Mn, Co and Cd as opposed to 2.3% of iron-replete subjects. The results confirm that low serum ferritin may have an impact on body kinetics of certain divalent metal ions, but not all. Only a fraction of women with low iron status exhibited an increased blood concentration of divalent metals, providing indication of complexities in the body's handling of these metals.

  4. Isotope-aided studies of the bioavailability of iron from Myanmar diets

    Energy Technology Data Exchange (ETDEWEB)

    Naing, Khin Maung [Department of Medical Research, Yangon (Myanmar). Nutrition Research Div.; Khin, Myo [Department of Medical Research, Yangon, (Myanmar). Nuclear Medicine Research Div.

    1994-12-31

    A study was conducted to determine the dietary intakes and serum levels of iron and zinc in twenty apparently healthy Myanmar adults (10 males and 10 females), using atomic absorption spetrophotometry. The mean iron intake of females was found to be lower than the FAO/WHO recommended allowance whereas for men it was found to be adequate. The mean serum iron concentration in females was found to be significantly lower than in males (p < 0.05). It was observed that zinc intakes of males was significantly higher than in females (p < 0.01) but there was no significant difference in serum zinc level between the two groups. Dietary zinc intakes of both groups were found to be low. There was a weak positive correlation between dietary intake and serum concentrations of these minerals. Laboratory scale production of iron-fortified salt containing 1 mg of Fe/g salt was conducted by mixing 5g of FeSO{sub 4{center_dot}}7H{sub 2}O, and 5g of sodium-hexa-metaphosphate thoroughly and then the mixture was again mixed with 1 kg of salt. This was done in July 1992. Stability of iron-fortified salt (i.e. change in colour of salt) as well as ferrous and ferric iron content of iron-fortified salt, were determined at monthly intervals. Iron-fortified salt was found to be stable up to the time of report writing, i.e. 3rd week of October, 1992. The ferrous iron content of salt was found to range between 0.95 to 0.98 mg Fe/g salt. Bioavailability studies of iron from two types of standard meals, one containing staple rice, 32 g of fish, water cress, watery fish paste and cucumber, and another containing boiled peas in place of fish, were conducted on two groups of male subjects using {sup 59}Fe as an extrinsic tag. Bioavailability studies of iron from the above two types of meals cooked with iron-fortified salt (1 mg/g salt) were also conducted on the same groups of subjects using {sup 59}Fe as an extrinsic tag. Reference dose absorption of iron will be conducted. This work is in progress.

  5. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... starch. Restless legs syndrome Shortness of breath Weakness Complications Undiagnosed or untreated iron-deficiency anemia may cause ... as complete blood count and iron studies. Prevent complications over your lifetime To prevent complications from iron- ...

  6. Role of brain iron accumulation in cognitive dysfunction: evidence from animal models and human studies.

    Science.gov (United States)

    Schröder, Nadja; Figueiredo, Luciana Silva; de Lima, Maria Noêmia Martins

    2013-01-01

    Over the last decades, studies from our laboratory and other groups using animal models have shown that iron overload, resulting in iron accumulation in the brain, produces significant cognitive deficits. Iron accumulation in the hippocampus and the basal ganglia has been related to impairments in spatial memory, aversive memory, and recognition memory in rodents. These results are corroborated by studies showing that the administration of iron chelators attenuates cognitive deficits in a variety of animal models of cognitive dysfunction, including aging and Alzheimer's disease models. Remarkably, recent human studies using magnetic resonance image techniques have also shown a consistent correlation between cognitive dysfunction and iron deposition, mostly in the hippocampus, cortical areas, and basal ganglia. These findings may have relevant implications in the light of the knowledge that iron accumulates in brain regions of patients suffering from neurodegenerative diseases. A better understanding of the functional consequences of iron dysregulation in aging and neurological diseases may help to identify novel targets for treating memory problems that afflict a growing aging population.

  7. Higher bioavailability of iron from whole wheat bread compared with iron-fortified white breads in caco-2 cell model: an experimental study.

    Science.gov (United States)

    Nikooyeh, Bahareh; Neyestani, Tirang R

    2017-06-01

    Bread, as the staple food of Iranians, with average per capita consumption of 300 g d -1 , could potentially be a good vehicle for many fortificants, including iron. In this study, iron bioavailability from flat breads (three fortified and one whole wheat unfortified) was investigated using in vitro simulation of gastrointestinal digestion and absorption in a caco-2 cell model. Despite having a lower ferritin/protein ratio in comparison with fortified breads, whole wheat bread showed higher iron bioavailability than the other three types of bread. Assuming iron bioavailability from the ferrous sulfate supplement used as standard was about 10%, the estimated bioavailability of iron from the test breads was calculated as 5.0-8.0%. Whole wheat bread (∼8%), as compared with the fortified breads (∼5-6.5%), had higher iron bioavailability. Iron from unfortified whole wheat bread is more bioavailable than from three types of iron-fortified breads. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  8. Moessbauer and EXAFS studies of amorphous iron produced by thermal decomposition of carbonyl iron in liquid phase

    International Nuclear Information System (INIS)

    Nomura, Kiyoshi; Tanaka, Junichi; Ujihira, Yusuke; Takahashi, Tamotu; Uchida, Yasuzo

    1990-01-01

    Decomposition of iron carbonyl Fe(CO) 5 and Fe 2 (CO) 9 in liquid phase gave amorphous and crystalline iron powders in the absence and presence of catalyst, respectively. The hyperfine fields were large in amorphous phases prepared from Fe(CO) 5 than from Fe 2 (CO) 9 . Crystalline iron, iron carbide and a trace amount of Fe 3 O 4 were detected in the decomposition products of the amorphous phase prepared from Fe(CO) 5 , and iron carbide was mainly included in the decomposition products of the amorphous phase prepared from Fe 2 (CO) 9 . (orig.)

  9. Pharmacokinetics study of Zr-89-labeled melanin nanoparticle in iron-overload mice

    International Nuclear Information System (INIS)

    Zhang, Pengjun; Yue, Yuanyuan; Pan, Donghui; Yang, Runlin; Xu, Yuping; Wang, Lizhen; Yan, Junjie; Li, Xiaotian; Yang, Min

    2016-01-01

    Melanin, a natural biological pigment present in many organisms, has been found to exhibit multiple functions. An important property of melanin is its ability to chelate metal ions strongly, which might be developed as an iron chelator for iron overload therapy. Herein, we prepared the ultrasmall water-soluble melanin nanoparticle (MP) and firstly evaluate the pharmacokinetics of MP in iron-overload mice to provide scientific basis for treating iron-overload. To study the circulation time and biodistribution, MP was labeled with 89 Zr, a long half-life (78.4 h) positron-emitting metal which is suited for the labeling of nanoparticles and large bioactive molecule. MP was chelated with 89 Zr directly at pH 5, resulting in non-decay-corrected yield of 89.6% and a radiochemical purity of more than 98%. The specific activity was at least190 MBq/μmol. The 89 Zr-MP was stable in human plasma and PBS for at least 48 h. The half-life of 89 Zr-MP was about 15.70 ± 1.74 h in iron-overload mice. Biodistribution studies and MicroPET imaging showed that 89 Zr-MP mainly accumulated in liver and spleen, which are the target organ of iron-overload. The results indicate that the melanin nanoparticle is promising for further iron overload therapy.

  10. Quantitative susceptibility mapping (QSM) as a means to measure brain iron? A post mortem validation study

    Science.gov (United States)

    Langkammer, Christian; Schweser, Ferdinand; Krebs, Nikolaus; Deistung, Andreas; Goessler, Walter; Scheurer, Eva; Sommer, Karsten; Reishofer, Gernot; Yen, Kathrin; Fazekas, Franz; Ropele, Stefan; Reichenbach, Jürgen R.

    2012-01-01

    Quantitative susceptibility mapping (QSM) is a novel technique which allows determining the bulk magnetic susceptibility distribution of tissue in vivo from gradient echo magnetic resonance phase images. It is commonly assumed that paramagnetic iron is the predominant source of susceptibility variations in gray matter as many studies have reported a reasonable correlation of magnetic susceptibility with brain iron concentrations in vivo. Instead of performing direct comparisons, however, all these studies used the putative iron concentrations reported in the hallmark study by Hallgren and Sourander (1958) for their analysis. Consequently, the extent to which QSM can serve to reliably assess brain iron levels is not yet fully clear. To provide such information we investigated the relation between bulk tissue magnetic susceptibility and brain iron concentration in unfixed (in situ) post mortem brains of 13 subjects using MRI and inductively coupled plasma mass spectrometry. A strong linear correlation between chemically determined iron concentration and bulk magnetic susceptibility was found in gray matter structures (r = 0.84, p < 0.001), whereas the correlation coefficient was much lower in white matter (r = 0.27, p < 0.001). The slope of the overall linear correlation was consistent with theoretical considerations of the magnetism of ferritin supporting that most of the iron in the brain is bound to ferritin proteins. In conclusion, iron is the dominant source of magnetic susceptibility in deep gray matter and can be assessed with QSM. In white matter regions the estimation of iron concentrations by QSM is less accurate and more complex because the counteracting contribution from diamagnetic myelinated neuronal fibers confounds the interpretation. PMID:22634862

  11. Quantitative Susceptibility Mapping Indicates a Disturbed Brain Iron Homeostasis in Neuromyelitis Optica ? A Pilot Study

    OpenAIRE

    Doring, Thomas Martin; Granado, Vanessa; Rueda, Fernanda; Deistung, Andreas; Reichenbach, Juergen R.; Tukamoto, Gustavo; Gasparetto, Emerson Leandro; Schweser, Ferdinand

    2016-01-01

    Dysregulation of brain iron homeostasis is a hallmark of many neurodegenerative diseases and can be associated with oxidative stress. The objective of this study was to investigate brain iron in patients with Neuromyelitis Optica (NMO) using quantitative susceptibility mapping (QSM), a quantitative iron-sensitive MRI technique. 12 clinically confirmed NMO patients (6 female and 6 male; age 35.4y±14.2y) and 12 age- and sex-matched healthy controls (7 female and 5 male; age 33.9±11.3y) underwen...

  12. Isotope aided studies of the bioavailability of iron and zinc from human diets consumed in Venezuela

    International Nuclear Information System (INIS)

    Layrisse, M.A.

    1994-01-01

    Previous studies on Venezuelan diets provided information on food consumed in each diet and their nutritional contents. It also showed the comparison of the iron absorption from these diets when given in the morning after over-night fast and when given at the customary time of the day. It was observed that the iron absorption from the lunch given at noon was slightly higher (although not significant) in Zulia and Sucre diets. There were no significant differences between the Zulia lunch given in the morning after over-night fast at noon. Similar results were observed in the Sucre diet lunch repeated twice. From these results we can state that iron absorption from meals is not affected by the time it is administered with the condition that the subjects tested have had a previous fast of three hours before the meal is administered. The significant difference in iron absorption in the first study could be due to a marked physiological daily variation in iron absorption. The results from these studies provide credit to previous reports in which meals were given in the morning after an over-night fast. The iron absorption studies from 11 diets consumed by the Venezuelan population, provided the basic information for the establishment of a programme on iron fortification. The Government of Venezuela, according to the recommendation of the National Nutrition Institute, approved a national programme of iron fortification by enriching precooked maize flour with ferrous fumarate in the proportion of 5 mg Fe/100 g flour, and the enrichment of flour used to produce paste with the same iron compound in the proportion of 3 mg Fe/100 g flour. This year, the Chemical Centre of the Venezuela Scientific Institute of Research discovered an iron compound, now called FERROIVIC. It is an insoluble white powder that, when given as iron fortification, forms part of the nonhaeme iron pool and it is absorbed to the same extent as ferrous sulphate; it is stable for several months. 15 refs, 8

  13. Study of corrosion using long period fiber gratings coated with iron exposed to salty water

    Science.gov (United States)

    Coelho, L.; Santos, J. L.; Jorge, P. A. S.; de Almeida, J. M. M.

    2017-04-01

    A study of long period fiber gratings (LPFG) over coated with iron (Fe) and subjected to oxidation in water with different sodium chloride (NaCl) concentrations is presented. The formation of iron oxides and hydroxides was monitored in real time by following the features of the LPFG attenuation band. Preliminary results show that Fe coated LPFGs can be used as sensors for early warning of corrosion in offshore and in coastal projects where metal structures made of iron alloys are in contact with sea or brackish water.

  14. Spin crossover studies in cationic complexes of iron by using Moessbauer spectroscopy

    International Nuclear Information System (INIS)

    Vadera, S.R.; Kumar, N.

    1990-01-01

    The spin transition in two new cationic complexes of iron, i.e. iron bipyridine formate, [Fe(bipy) 3 ](HCOO) 2 .5(HCOOH) and iron bipyridine tetrafluoro borate, [Fe(bipy) 3 ](BF 4 ) 2 .2H 2 O were studied by Moessbauer spectroscopy. From quadrupole splitting values, it was established that at different temperatures both complexes show the coexistence of both high spin state and low spin state at 300 K, while complete transformation to low spin state occurs at 77 K. Both compounds were prepared by electrochemical technique. (author) 12 refs.; 1 fig.; 1 tab

  15. Virtual iron concentration imaging based on dual-energy CT for noninvasive quantification and grading of liver iron content: An iron overload rabbit model study

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Xian Fu; Yang, Yi; Xie, Xue Qian; Zhang, Huan; Chai, Wei Min; Yan, Fu Hua [Shanghai Jiao Tong University School of Medicine, Department of Radiology, Ruijin Hospital, Shanghai (China); Yan, Jing [Siemens Shanghai Medical Equipment Ltd., Shanghai (China); Wang, Li [Fudan University, Center of Analysis and Measurement, Shanghai (China); Schmidt, Bernhard [Siemens AG, Healthcare Sector, Forchheim (Germany)

    2015-09-15

    To assess the accuracy of liver iron content (LIC) quantification and grading ability associated with clinical LIC stratification using virtual iron concentration (VIC) imaging on dual-energy CT (DECT) in an iron overload rabbit model. Fifty-one rabbits were prepared as iron-loaded models by intravenous injection of iron dextran. DECT was performed at 80 and 140 kVp. VIC images were derived from an iron-specific algorithm. Postmortem LIC assessments were conducted on an inductively coupled plasma (ICP) spectrometer. Correlation between VIC and LIC was analyzed. VIC were stratified according to the corresponding clinical LIC thresholds of 1.8, 3.2, 7.0, and 15.0 mg Fe/g. Diagnostic performance of stratification was evaluated by receiver operating characteristic analysis. VIC linearly correlated with LIC (r = 0.977, P < 0.01). No significant difference was observed between VIC-derived LICs and ICP (P > 0.05). For the four clinical LIC thresholds, the corresponding cutoff values of VIC were 19.6, 25.3, 36.9, and 61.5 HU, respectively. The highest sensitivity (100 %) and specificity (100 %) were achieved at the threshold of 15.0 mg Fe/g. Virtual iron concentration imaging on DECT showed potential ability to accurately quantify and stratify hepatic iron accumulation in the iron overload rabbit model. (orig.)

  16. Are there anamnestic risk factors for iron deficiency in pregnancy? Results from a feasibility study.

    Science.gov (United States)

    Kirschner, Wolf; Dudenhausen, Joachim W; Henrich, Wolfgang

    2016-04-01

    The conditions of iron deficiency are highly incident in pregnancy with elevated risks for preterm birth and low birth weight. In our recent study, we found 6% of participants having anemia, whereas between 39% and 47% showed iron deficiency without anemia. In many countries in prenatal care solely hemoglobin (Hb) measurement is applied. For the gynecologists till date there is no indication to determine other markers (e.g., serum-ferritin). As iron deficiency results from an imbalance between intake and loss of iron, our aim was to find out if the risk of iron deficiency conditions can be estimated by a diet history protocol as well as questionnaires to find about iron loss. We found that the risk of having iron deficiency in upper gestational week (>=21) increased by a factor of five. Thus, additional diagnostics should be done in this group by now. Using the questionnaire as a screening instrument, we further estimated the probability of disease in terms of a positive likelihood ratio (LR+). The positive LR for the group below 21th week of gestation is 1.9 thus, increasing the post-test probability to 52% from 36% as before. Further research based on higher sample sizes will show if the ratios can be increased further.

  17. Diagnosis of hepatic iron overload: a family study illustrating pitfalls in diagnosing hemochromatosis.

    Science.gov (United States)

    Schranz, Melanie; Talasz, Heribert; Graziadei, Ivo; Winder, Thomas; Sergi, Consolato; Bogner, Klaus; Vogel, Wolfgang; Zoller, Heinz

    2009-03-01

    Recent identification of genetic variants in iron storage disease has changed the classification system and diagnostic algorithms for hemochromatosis. Clinical diagnosis of the disease requires phenotypic evidence of iron overload because the commonly disease-associated HFE genotypes have an incomplete penetrance. Furthermore, approximately 20% of patients with a clinical diagnosis of hemochromatosis have no disease-associated genotype, which underlines the importance of clear phenotypic criteria of hemochromatosis. A diagnosis of hemochromatosis cannot be made even in patients with liver cirrhosis simply on the basis of genetic testing that indicates that iron overload is the cause of the disease and not its consequence. Proper diagnosis requires integration of clinical presentation, family history, and the results of biochemical and histopathologic tests. Here we propose a rational diagnostic algorithm for hepatic iron overload syndromes and illustrate potential pitfalls by presenting a family study in a pedigree with rare HFE variants (H63D and E168Q), in cis on the same chromosome. Although the clinical suspicion of hemochromatosis was confirmed by histology, chemical analysis of liver tissue revealed a normal hepatic iron concentration, which is compatible with the genetic finding of 1 normal and 1 doubly mutated allele. In conclusion, clinical suspicion of hemochromatosis and elevated serum iron parameters should prompt HFE genotyping for C282Y and H63D. Should they be uninformative, further genetic tests should be recommended only if iron overload in liver tissue has been confirmed chemically.

  18. Potential involvement of iron in the pathogenesis of peritoneal endometriosis.

    Science.gov (United States)

    Defrère, S; Lousse, J C; González-Ramos, R; Colette, S; Donnez, J; Van Langendonckt, A

    2008-07-01

    The aim of this study is to review the current literature associating endometriosis with iron and to discuss the potential causes and consequences of iron overload in the pelvic cavity. Indeed, iron is essential for all living organisms. However, excess iron can result in toxicity and is associated with pathological disorders. In endometriosis patients, iron overload has been demonstrated in the different components of the peritoneal cavity (peritoneal fluid, endometriotic lesions, peritoneum and macrophages). Animal models allow us to gather essential information on the origin, metabolism and effect of iron overload in endometriosis, which may originate from erythrocytes carried into the pelvic cavity mainly by retrograde menstruation. Peritoneal macrophages play an important role in the degradation of these erythrocytes and in subsequent peritoneal iron metabolism. Iron overload could affect a wide range of mechanisms involved in endometriosis development, such as oxidative stress or lesion proliferation. In conclusion, excess iron accumulation can result in toxicity and may be one of the factors contributing to the development of endometriosis. Treatment with an iron chelator could thus be beneficial in endometriosis patients to prevent iron overload in the pelvic cavity, thereby diminishing its deleterious effect.

  19. A comparative study on androgen metabolism in three invertebrate species.

    Science.gov (United States)

    Janer, G; LeBlanc, G A; Porte, C

    2005-09-15

    A comparative approach was taken in this study to evaluate androgen (androstenedione and testosterone) metabolism in three invertebrate species: the gastropod Marisa cornuarietis, the amphipod Hyalella azteca, and the echinoderm Paracentrotus lividus. The existence of 17beta/3beta-hydroxysteroid dehydrogenase (HSD) and 5alpha-reductase catalyzed reactions was demonstrated in all three species. Androstenedione was primarily converted to 5alpha-androstanedione in M. cornuarietis, while it was primarily metabolized to testosterone in P. lividus and H. azteca. In addition, and consistent with vertebrate findings, tissue specific pathways and sexual dimorphism in androgen metabolism were observed. Namely, testosterone was metabolized to dihydrotestosterone in P. lividus gonads (via 5alpha-reductase), and metabolized to 4-androstene-3beta,17beta-diol in the digestive tube (via 3beta-hydroxysteroid dehydrogenase). Furthermore, the synthesis of 17beta-reduced metabolites of androstenedione (testosterone and dihydrotestosterone) was 3- to 4-fold higher in males of M. cornuarietis than in females. Organotin compounds, which have been shown to interfere with some aspects of androgen metabolism, had no major effect on testosterone metabolism in any of the three species. Fenarimol enhanced 5alpha-reductase-mediated catalysis in gonads of P. lividus. Overall, results demonstrate the ubiquity of some androgen biotransformation processes in invertebrates and reveals interphyla differences in androgen metabolic pathways, and different sensitivity of these pathways to some xenobiotics.

  20. Urinary Hepcidin Levels in Iron-Deficient and Iron-Supplemented Piglets Correlate with Hepcidin Hepatic mRNA and Serum Levels and with Body Iron Status.

    Directory of Open Access Journals (Sweden)

    Robert Staroń

    Full Text Available Among livestock, domestic pig (Sus scrofa is a species, in which iron metabolism has been most intensively examined during last decade. The obvious reason for studying the regulation of iron homeostasis especially in young pigs is neonatal iron deficiency anemia commonly occurring in these animals. Moreover, supplementation of essentially all commercially reared piglets with iron entails a need for monitoring the efficacy of this routine practice followed in the swine industry for several decades. Since the discovery of hepcidin many studies confirmed its role as key regulator of iron metabolism and pointed out the assessment of its concentrations in biological fluids as diagnostic tool for iron-related disorder. Here we demonstrate that urine hepcidin-25 levels measured by a combination of weak cation exchange chromatography and time-of-flight mass spectrometry (WCX-TOF MS are highly correlated with mRNA hepcidin expression in the liver and plasma hepcidin-25 concentrations in anemic and iron-supplemented 28-day old piglets. We also found a high correlation between urine hepcidin level and hepatic non-heme iron content. Our results show that similarly to previously described transgenic mouse models of iron disorders, young pigs constitute a convenient animal model to explore accuracy and relationship between indicators for assessing systemic iron status.

  1. Iron and cell death in Parkinson's disease: a nuclear microscopic study into iron-rich granules in the parkinsonian substantia nigra of primate models

    Energy Technology Data Exchange (ETDEWEB)

    Thong, P.S.P.; Watt, F. E-mail: phywattf@nus.edu.sg; Ponraj, D.; Leong, S.K.; He, Y.; Lee, T.K.Y

    1999-09-02

    Parkinson's disease is a degenerative brain disease characterised by a loss of cells in the substantia nigra (SN) region of the brain and accompanying biochemical changes such as inhibition of mitochondrial function, increased iron concentrations and decreased glutathione levels in the parkinsonian SN. Though the aetiology of the disease is still unknown, the observed biochemical changes point to the involvement of oxidative stress. In particular, iron is suspected to play a role by promoting free radical production, leading to oxidative stress and cell death. The increase in iron in the parkinsonian SN has been confirmed by several research groups, both in human post-mortem brains and in brain tissue from parkinsonian animal models. However, the question remains as to whether the observed increase in iron is a cause or a consequence of the SN cell death process. Our previous study using unilaterally 1-methyl-4-phenyl-1,2,3,6-tetrahydro-pyridine (MPTP)-lesioned monkeys in a time sequence experiment has shown that the increase in bulk iron concentrations follow rather than precede dopaminergic cell death. However, changes in the localised iron concentrations, which may play a more direct role in SN cell death, may not be reflected at the bulk level. Indeed, we have observed iron-rich granules in parkinsonian SNs. From this time sequence study into the iron content of iron-rich granules in the SNs of an untreated control and unilaterally MPTP-lesioned parkinsonian models, we present the following observations: (1) Iron-rich granules are found in both control and parkinsonian SNs and are variable in size and iron content in any one model. (2) These iron-rich granules may be associated with neuromelanin granules found in the SN and are known to accumulate transition metal ions such as iron. (3) The early onset of bulk SN cell loss (35%) was accompanied by a significant elevation of iron in granules found in the MPTP-injected SN compared to the contra-lateral SN

  2. Kinetic studies on the oxidation of oxyhemoglobin by biologically active iron thiosemicarbazone complexes: relevance to iron-chelator-induced methemoglobinemia.

    Science.gov (United States)

    Basha, Maram T; Rodríguez, Carlos; Richardson, Des R; Martínez, Manuel; Bernhardt, Paul V

    2014-03-01

    The oxidation of oxyhemoglobin to methemoglobin has been found to be facilitated by low molecular weight iron(III) thiosemicarbazone complexes. This deleterious reaction, which produces hemoglobin protein units unable to bind dioxygen and occurs during the administration of iron chelators such as the well-known 3-aminopyridine-2-pyridinecarbaldehyde thiosemicarbazone (3-AP; Triapine), has been observed in the reaction with Fe(III) complexes of some members of the 3-AP structurally-related thiosemicarbazone ligands derived from di-2-pyridyl ketone (HDpxxT series). We have studied the kinetics of this oxidation reaction in vitro using human hemoglobin and found that the reaction proceeds with two distinct time-resolved steps. These have been associated with sequential oxidation of the two different oxyheme cofactors in the α and β protein chains. Unexpected steric and hydrogen-bonding effects on the Fe(III) complexes appear to be the responsible for the observed differences in the reaction rate across the series of HDpxxT ligand complexes used in this study.

  3. Assessment of Iron Deficiency and Anemia in Pregnant Women: An Observational French Study

    Science.gov (United States)

    Harvey, Thierry; Zkik, Asmaa; Auges, Marie; Clavel, Thierry

    2016-01-01

    Aim: We explored the prevalence and management of iron deficiency and anemia among pregnant women in France. Patients & methods: In this prospective, observational, multicenter registry study, randomly selected investigators (gynecologists/obstetricians/midwives registered in the CEGEDIM® database) assessed pregnant women presenting for a consultation. Participants completed a questionnaire at study inclusion. Results: A total of 1506 patients were enrolled by 95 investigators. Overall, investigators estimated a moderate or significant risk of iron deficiency in almost 60% of women. The overall prevalence of anemia (15.8%) increased with longer pregnancy duration. Medication (mainly iron-based) was prescribed to 57.3% of patients. Conclusion: In French clinical practice, the estimated risk of iron deficiency and prevalence of anemia during pregnancy align with expectations and are managed according to national/international recommendations. PMID:26693881

  4. A Study on Removal of Environmental Pollution Materials with Nano-scale Iron Particles

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Myung Ho; Ahn, Hong Ju

    2009-07-15

    In this study, a method of nano-sized iron particles with zero valent state was developed. Also, the optimum conditions for the synthesis of silica based micro-particles were obtained for micro particle analysis. Basic physical data for standard particles were obtained in various synthesis conditions for mass production. From the experiment of removal of Pb in the solution with iron particles with zero valent state, most of Pb was removed from the solution over pH 7, as a result of reaction of Pb with iron particles with zero valent state. Nano sized iron particles with zero valent state obtained from this study will be apply for removing heavy metals and radionuclides as well as waste treatment and remediation for contaminated materials in the environment.

  5. Study of the solubility of iron in zirconium by thermoelectric power measurements

    International Nuclear Information System (INIS)

    Borrelly, R.; Merle, P.; Adami, L.; Centre National de la Recherche Scientifique, 69 - Villeurbanne

    1990-01-01

    Thermoelectric power (TEP) measurements are used to determine the solubility of iron in α-zirconium. A preliminary study shows that TEP is very sensitive to elements in solid solution, to cold-working and to the texture due to rolling in a temperature range including room temperature which is choosen for thermoelectric power measurements. The solutioning of iron obtained by a homogenization treatment and water-quench leads to a decrease of thermoelectric power. The conditions of homogenization treatments such that TEP variations are only due to the variation of iron content in solid solution have been determined. From these results the solubility of iron α-zirconium as a function of temperature has been determined. Moreover, the α-domain of the Zr-rich part of the Zr-Fe diagram has been completely delimited. A micrographic study has been made to confirm these results. (orig.)

  6. Glutathione, Glutaredoxins, and Iron.

    Science.gov (United States)

    Berndt, Carsten; Lillig, Christopher Horst

    2017-11-20

    Glutathione (GSH) is the most abundant cellular low-molecular-weight thiol in the majority of organisms in all kingdoms of life. Therefore, functions of GSH and disturbed regulation of its concentration are associated with numerous physiological and pathological situations. Recent Advances: The function of GSH as redox buffer or antioxidant is increasingly being questioned. New functions, especially functions connected to the cellular iron homeostasis, were elucidated. Via the formation of iron complexes, GSH is an important player in all aspects of iron metabolism: sensing and regulation of iron levels, iron trafficking, and biosynthesis of iron cofactors. The variety of GSH coordinated iron complexes and their functions with a special focus on FeS-glutaredoxins are summarized in this review. Interestingly, GSH analogues that function as major low-molecular-weight thiols in organisms lacking GSH resemble the functions in iron homeostasis. Since these iron-related functions are most likely also connected to thiol redox chemistry, it is difficult to distinguish between mechanisms related to either redox or iron metabolisms. The ability of GSH to coordinate iron in different complexes with or without proteins needs further investigation. The discovery of new Fe-GSH complexes and their physiological functions will significantly advance our understanding of cellular iron homeostasis. Antioxid. Redox Signal. 27, 1235-1251.

  7. Iron Status and Inflammation in Early Stages of Chronic Kidney Disease

    Directory of Open Access Journals (Sweden)

    Ewelina Łukaszyk

    2015-06-01

    Full Text Available Background/Aims: One of the most common causes of anemia of chronic disease (ACD is chronic kidney disease. The main pathomechanism responsible for ACD is subclinical inflammation. The key element involved in iron metabolism is hepcidin, however, studies on new indices of iron status are in progress.The aim of the study was to assess the iron status in patients in early stages of chronic kidney disease, iron correlation with inflammation parameters and novel biomarkers of iron metabolism. Methods: The study included 69 patients. Standard laboratory measurements were used to measure the iron status, complete blood count, fibrinogen, prothrombin index, C-reactive protein concentration (CRP, creatinine, urea, uric acid. Commercially available kits were used to measure high-sensitivity CRP, interleukin 6 (IL-6, hepcidin-25, hemojuvelin, soluble transferrin receptor (sTfR, growth differentiation factor-15 (GDF-15 and zonulin. Results: Absolute iron deficiency was present in 17% of the patients, functional iron deficiency was present in 12% of the patients. Functional iron deficiency was associated with significantly higher serum levels of fibrinogen, ferritin, transferrin saturation, total iron binding capacity, hepcidin and older age relative to patients with absolute iron deficiency. In comparison with patients without iron deficiency, patients with functional iron deficiency were older, with lower prothrombin index, higher fibrinogen, CRP, hsCRP, sTfR, GDF-15, urea and lower eGFR. Hepcidin was predicted by markers of inflammation:ferritin, fibrinogen and IL-6. Conclusion: Inflammation is correlated with iron status. Novel biomarkers of iron metabolism might be useful to distinguish iron deficiency anemia connected with inflammation and absolute iron deficiency.

  8. XPS and FTIR spectroscopic study on microwave treated high phosphorus iron ore

    Energy Technology Data Exchange (ETDEWEB)

    Omran, Mamdouh, E-mail: mamdouh.omran@oulu.fi [Process Metallurgy Research Group, Faculty of Technology, University of Oulu (Finland); Mineral Processing and Agglomeration Lab, Central Metallurgical Research and Development Institute, Cairo (Egypt); Fabritius, Timo [Process Metallurgy Research Group, Faculty of Technology, University of Oulu (Finland); Elmahdy, Ahmed M.; Abdel-Khalek, Nagui A. [Mineral Processing and Agglomeration Lab, Central Metallurgical Research and Development Institute, Cairo (Egypt); El-Aref, Mortada; Elmanawi, Abd El-Hamid [Geology Department, Faculty of Science, Cairo University, Giza 12613 (Egypt)

    2015-08-01

    Highlights: • The effect of microwave radiation on structure and chemical state of high phosphorus iron ore was studied. • FTIR analyses showed that after microwave radiation the functional chemical groups of phosphorus bearing minerals (fluorapatite) dissociated. • High resolution XPS analyses of Fe 2p peaks showed that after microwave radiation a portion of Fe(+III) was reduced to Fe(+II). • Microwave radiation had a positive effect on the magnetic properties of iron oxide, through formation of ferromagnetic phases. - Abstract: A growing interest in microwave heating has emerged recently. Several potential microwave applications regarding minerals’ processing have been investigated. This paper investigates the effect of microwave radiation on Egyptian high phosphorus iron ore. Three different iron ore samples have varying Fe{sub 2}O{sub 3} and P{sub 2}O{sub 5} contents and mineralogical textures were studied. A comparative study has been carried out between untreated and microwave treated iron ore. XRD and FTIR analyses showed that after microwave radiation the crystallinity of iron bearing minerals (hematite) increased, while the functional chemical groups of phosphorus bearing minerals (fluorapatite) and other gangues dissociated. High resolution XPS analyses of Fe 2p peaks showed that after microwave radiation a portion of Fe(+III) was reduced to Fe(+II). This means that after microwave radiation iron oxide (hematite, Fe{sup 3+}) transformed into more magnetic phase. The results indicated that microwave radiation had a positive effect on the magnetic properties of iron oxide, through formation of ferromagnetic phases.

  9. Radiocarbon dating study of ancient iron artifacts with accelerator mass spectrometry

    International Nuclear Information System (INIS)

    Igaki, Kenzo; Nakamura, Toshio; Hirasawa, Masahiro; Kato, Masako; Sano, Masamichi.

    1994-01-01

    In order to study the correlation between the highly resistive property against corrosion and the production method of the ancient iron artifacts, it is essentially necessary to determine the accurate ages of them. 14 C dating with accelerator mass spectrometry was applied to the two ancient artifacts, a Japanese sword of wrought iron with a production age ranged from the Kamakura to the Muromachi period, estimation based on the fabrication technique, and a planning adze of cast iron with no definite origin. The former was dated as 880±150 y.B.P., corresponding to the calendar age ranged from AD 1021 to AD 1263, and the latter as 1720±160 y.B.P. with the calendar age ranged from AD 119 to AD 457 and from AD 483 to AD 508. These calibrated 14 C ages for both iron artifacts are consistent with the relevant ages conjectured by historical considerations. (author)

  10. Structural properties of iron nitride on Cu(100): An ab-initio molecular dynamics study

    KAUST Repository

    Heryadi, Dodi

    2011-01-01

    Due to their potential applications in magnetic storage devices, iron nitrides have been a subject of numerous experimental and theoretical investigations. Thin films of iron nitride have been successfully grown on different substrates. To study the structural properties of a single monolayer film of FeN we have performed an ab-initio molecular dynamics simulation of its formation on a Cu(100) substrate. The iron nitride layer formed in our simulation shows a p4gm(2x2) reconstructed surface, in agreement with experimental results. In addition to its structural properties, we are also able to determine the magnetization of this thin film. Our results show that one monolayer of iron nitride on Cu(100) is ferromagnetic with a magnetic moment of 1.67 μ B. © 2011 Materials Research Society.

  11. Iron and genome stability: An update

    International Nuclear Information System (INIS)

    Prá, Daniel; Franke, Silvia Isabel Rech; Henriques, João Antonio Pêgas; Fenech, Michael

    2012-01-01

    Iron is an essential micronutrient which is required in a relatively narrow range for maintaining metabolic homeostasis and genome stability. Iron participates in oxygen transport and mitochondrial respiration as well as in antioxidant and nucleic acid metabolism. Iron deficiency impairs these biological pathways, leading to oxidative stress and possibly carcinogenesis. Iron overload has been linked to genome instability as well as to cancer risk increase, as seen in hereditary hemochromatosis. Iron is an extremely reactive transition metal that can interact with hydrogen peroxide to generate hydroxyl radicals that form the 8-hydroxy-guanine adduct, cause point mutations as well as DNA single and double strand breaks. Iron overload also induces DNA hypermethylation and can reduce telomere length. The current Recommended Dietary Allowances (RDA) for iron, according with Institute of Medicine Dietary Reference Intake (DRI), is based in the concept of preventing anemia, and ranges from 7 mg/day to 18 mg/day depending on life stage and gender. Pregnant women need 27 mg/day. The maximum safety level for iron intake, the Upper Level (UL), is 40–45 mg/day, based on the prevention of gastrointestinal distress associated to high iron intakes. Preliminary evidence indicates that 20 mg/day iron, an intake slightly higher than the RDA, may reduce the risk of gastrointestinal cancer in the elderly as well as increasing genome stability in lymphocytes of children and adolescents. Current dietary recommendations do not consider the concept of genome stability which is of concern because damage to the genome has been linked to the origin and progression of many diseases and is the most fundamental pathology. Given the importance of iron for homeostasis and its potential influence over genome stability and cancer it is recommended to conduct further studies that conclusively define these relationships.

  12. Iron and genome stability: An update

    Energy Technology Data Exchange (ETDEWEB)

    Pra, Daniel, E-mail: daniel_pra@yahoo.com [PPG em Promocao da Saude, Universidade de Santa Cruz do Sul (UNISC), Santa Cruz do Sul, RS (Brazil); PPG em Saude e Comportamento, Universidade Catolica de Pelotas, Pelotas, RS (Brazil); Franke, Silvia Isabel Rech [PPG em Promocao da Saude, Universidade de Santa Cruz do Sul (UNISC), Santa Cruz do Sul, RS (Brazil); Henriques, Joao Antonio Pegas [Instituto de Biotecnologia, Universidade de Caxias do Sul, Caxias do Sul, RS (Brazil); Fenech, Michael [CSIRO Food and Nutritional Sciences, Adelaide, SA (Australia)

    2012-05-01

    Iron is an essential micronutrient which is required in a relatively narrow range for maintaining metabolic homeostasis and genome stability. Iron participates in oxygen transport and mitochondrial respiration as well as in antioxidant and nucleic acid metabolism. Iron deficiency impairs these biological pathways, leading to oxidative stress and possibly carcinogenesis. Iron overload has been linked to genome instability as well as to cancer risk increase, as seen in hereditary hemochromatosis. Iron is an extremely reactive transition metal that can interact with hydrogen peroxide to generate hydroxyl radicals that form the 8-hydroxy-guanine adduct, cause point mutations as well as DNA single and double strand breaks. Iron overload also induces DNA hypermethylation and can reduce telomere length. The current Recommended Dietary Allowances (RDA) for iron, according with Institute of Medicine Dietary Reference Intake (DRI), is based in the concept of preventing anemia, and ranges from 7 mg/day to 18 mg/day depending on life stage and gender. Pregnant women need 27 mg/day. The maximum safety level for iron intake, the Upper Level (UL), is 40-45 mg/day, based on the prevention of gastrointestinal distress associated to high iron intakes. Preliminary evidence indicates that 20 mg/day iron, an intake slightly higher than the RDA, may reduce the risk of gastrointestinal cancer in the elderly as well as increasing genome stability in lymphocytes of children and adolescents. Current dietary recommendations do not consider the concept of genome stability which is of concern because damage to the genome has been linked to the origin and progression of many diseases and is the most fundamental pathology. Given the importance of iron for homeostasis and its potential influence over genome stability and cancer it is recommended to conduct further studies that conclusively define these relationships.

  13. A theoretical study of carbohydrates as corrosion inhibitors of iron

    Energy Technology Data Exchange (ETDEWEB)

    Khalil, Salim M.; Ali, Nozha M. [Libyan Academy for Graduate Studies, Tripoli (Libyan Arab Jamahiriya). Chemistry Dept.; Ali-Shattle, Elbashir E. [Tripoli Univ. (Libyan Arab Jamahiriya). Chemistry Dept.

    2013-08-15

    The inhibitive effect of fructose, glucose, lactose, maltose, and sucrose against the iron corrosion is investigated using density functional theory at the B3LYP/6-31 G level (d) to search the relation between the molecular structure and corrosion inhibition. The electronic properties such as the energy of the highest occupied molecular orbital (HOMO), the energy of lowest unoccupied orbital (LUMO), the energy gap (LUMO-HOMO), quantum chemical parameters such as hardness, softness, the fraction of the electron transferred, and the electrophilicity index are reported. The inhibition efficiency of the investigated carbohydrates follows the trend: maltose < sucrose < lactose < fructose < glucose. (orig.)

  14. Study of holograms made with saccharides and iron ions

    Science.gov (United States)

    Ordóñez-Padilla, M. M.; Olivares-Pérez, A.; Dorantes-García, V.; Vallejo-Mendoza, R.; Fuentes-Tapia, I.

    2012-03-01

    We present the performance characterization of photosensitive film emulsions prepared with saccharides like: pectin, fructose and sugar (Glass ®), at certain physicochemical conditions for holographic recording. The photo-oxidation was carried out with concentrations of iron ions, Fe+3. We analyzed the parameters of the diffraction efficiencies of each grating constructed with saccharides film. The work was to achieve stability and non-toxicity of the films prepared easily with water-Fe ions. We performed an experimental comparison of the holographic films capacity between the three saccharides.

  15. Alterations of systemic and muscle iron metabolism in human subjects treated with low-dose recombinant erythropoietin

    DEFF Research Database (Denmark)

    Robach, Paul; Recalcati, Stefania; Girelli, Domenico

    2009-01-01

    healthy volunteers were treated with recombinant erythropoietin (rhEpo) for 1 month. As expected, the treatment efficiently increased erythropoiesis and stimulated bone marrow iron use. It was also associated with a prompt and considerable decrease in urinary hepcidin and a slight transient increase...

  16. Brain glucose metabolism during hypoglycemia in type 1 diabetes: insights from functional and metabolic neuroimaging studies.

    Science.gov (United States)

    Rooijackers, Hanne M M; Wiegers, Evita C; Tack, Cees J; van der Graaf, Marinette; de Galan, Bastiaan E

    2016-02-01

    Hypoglycemia is the most frequent complication of insulin therapy in patients with type 1 diabetes. Since the brain is reliant on circulating glucose as its main source of energy, hypoglycemia poses a threat for normal brain function. Paradoxically, although hypoglycemia commonly induces immediate decline in cognitive function, long-lasting changes in brain structure and cognitive function are uncommon in patients with type 1 diabetes. In fact, recurrent hypoglycemia initiates a process of habituation that suppresses hormonal responses to and impairs awareness of subsequent hypoglycemia, which has been attributed to adaptations in the brain. These observations sparked great scientific interest into the brain's handling of glucose during (recurrent) hypoglycemia. Various neuroimaging techniques have been employed to study brain (glucose) metabolism, including PET, fMRI, MRS and ASL. This review discusses what is currently known about cerebral metabolism during hypoglycemia, and how findings obtained by functional and metabolic neuroimaging techniques contributed to this knowledge.

  17. Applications of deuterium labeling in studies of drug metabolism: metabolism of trideuteroaniline mustard

    International Nuclear Information System (INIS)

    Cox, P.J.; Farmer, P.B.; Foster, A.B.; Jarman, M.

    1977-01-01

    In a continuation of a study of aniline mustard, the metabolism of 2,4,6-trideuteroaniline mustard [N-N-di-(2-chloroethyl)-2,4,6-trideuteroaniline] was investigated. Measurements of the ratios of deuterated to nondeuterated species in p-hydroxyaniline mustard and N-(2-chloroethyl)-4-hydroxyaniline isolated following in vitro metabolism of a mixture of aniline mustard and aniline mustard-d 3 enabled a determination both of the kinetic isotope effect and of the extents of NIH shifts and indicated the probable metabolite sequence

  18. Bioavailable iron in typical Thai meals: Comparative studies between radioactive in vitro and in vivo food iron absorption measurements

    International Nuclear Information System (INIS)

    Sritongkul, N.

    1989-03-01

    Presently available in vivo methods for assessing iron absorption in human subjects, although physiologically acceptable and accurate, are not practical for screening large numbers of food and diet samples. A simple in vitro method for determining the amount of iron available for absorption was therefore investigated. It is based on the common pool concept of food iron absorption using radioactive Fe-59 as a marker of the iron present in the bioavailable iron pool. The ionizable iron was measured after an initial peptic digestion by using pepsin/HCl at pH 1.35 followed by an increase of the pH to 6.0 to simulate duodenal alkalinity. The method was proved to be simple, reproducible and applicable either to single food items or whole meals of varying composition. It is able to detect known enhancers or inhibitors of food iron absorption. The percent ionizable iron among 5 different meals with the inclusion of inhibitor or enhancer was shown to correlate closely with the percentage of iron absorbed in human subjects (r=0.9197, p<0.001). A high correlation between the in vivo and in vitro methods was also observed when the results were expressed as absorption ratios and ionizable ratios (r=0.9192, p<0.001). The method is expected to be useful for improving diet composition to increase the iron availability of some typical meals in developing countries, including those which are known to contain considerable amounts of inhibitors of iron absorption. 39 refs, 1 fig., 13 tabs

  19. Isotopic studies of urea metabolism in rabbits

    Science.gov (United States)

    Regoeczi, E.; Irons, L.; Koj, A.; McFarlane, A. S.

    1965-01-01

    1. The half-life of [15N]urea was found to be significantly longer than that of [14C]urea injected at the same time, the differences being due to endogenous catabolism of urea, which is accompanied by little or no reutilization of 14C but is approx. 20% for 15N. [15N]Urea therefore appears to be valueless as an indicator of nitrogen metabolism unless the extents of endogenous catabolism of urea and of fractional reutilization of 15N can be separately estimated. 2. Though measurements of the radioactivity of expired 14CO2 confirmed the existence of considerable urea catabolism these could not be used for quantitative assessments. 3. Alternative graphical methods based on [14C]urea specific activities in plasma and urine samples were used to calculate the fraction of urea production that is excreted. Values by the two methods were in good agreement and showed that some animals excrete less than half the urea that they produce. 4. Specific activity differences between simultaneous samples of urinary and plasma urea reflect the presence of a pool of urea in the kidney that is not in equilibrium with the body urea pool. Calculations indicate the presence of urea in the kidney that in some cases may represent as much as 15% of the body pool, and in two animals in which post-mortem renal analyses were performed the masses of urea found agreed closely with the calculated values. 5. A model for urea metabolism is proposed that includes this pool in the excretory pathway. The related theory is shown to be adequate to explain the shape of the specific activity curves of urinary urea from the time of injection and the constant delay of the specific activity of urinary urea, relative to that of plasma urea, that is observed after a short preliminary equilibration period. 6. The body urea pool was calculated from the activity retained at 1·5hr. by excluding renal activity and the corrected specific activity of plasma urea at the same time. The urea pool was calculated to be

  20. Obesity alters adipose tissue macrophage iron content and tissue iron distribution.

    Science.gov (United States)

    Orr, Jeb S; Kennedy, Arion; Anderson-Baucum, Emily K; Webb, Corey D; Fordahl, Steve C; Erikson, Keith M; Zhang, Yaofang; Etzerodt, Anders; Moestrup, Søren K; Hasty, Alyssa H

    2014-02-01

    Adipose tissue (AT) expansion is accompanied by the infiltration and accumulation of AT macrophages (ATMs), as well as a shift in ATM polarization. Several studies have implicated recruited M1 ATMs in the metabolic consequences of obesity; however, little is known regarding the role of alternatively activated resident M2 ATMs in AT homeostasis or how their function is altered in obesity. Herein, we report the discovery of a population of alternatively activated ATMs with elevated cellular iron content and an iron-recycling gene expression profile. These iron-rich ATMs are referred to as MFe(hi), and the remaining ATMs are referred to as MFe(lo). In lean mice, ~25% of the ATMs are MFe(hi); this percentage decreases in obesity owing to the recruitment of MFe(lo) macrophages. Similar to MFe(lo) cells, MFe(hi) ATMs undergo an inflammatory shift in obesity. In vivo, obesity reduces the iron content of MFe(hi) ATMs and the gene expression of iron importers as well as the iron exporter, ferroportin, suggesting an impaired ability to handle iron. In vitro, exposure of primary peritoneal macrophages to saturated fatty acids also alters iron metabolism gene expression. Finally, the impaired MFe(hi) iron handling coincides with adipocyte iron overload in obese mice. In conclusion, in obesity, iron distribution is altered both at the cellular and tissue levels, with AT playing a predominant role in this change. An increased availability of fatty acids during obesity may contribute to the observed changes in MFe(hi) ATM phenotype and their reduced capacity to handle iron.

  1. Reticulocyte Hemoglobin Content Helps Avoid Iron Overload in Hemodialysis Patients: A Retrospective Observational Study.

    Science.gov (United States)

    Capone, Domenico; Cataldi, Mauro; Vinciguerra, Mauro; Mosca, Teresa; Barretta, Salvatore; Ragosta, Annalisa; Sorrentino, Aniello; Vecchione, Alessandra; Barretta, Luca; Tarantino, Giovanni

    2017-01-01

    Anemia in patients suffering from end-stage renal failure is currently treated with Erythropoiesis-Stimulating Agents (ESA). This treatment needs sufficient iron supplementation to avoid an inadequate dosage of ESA. Nowadays modern analytical instruments allow to accurately calculate the content of Hemoglobin (Hb) in reticulocytes (CHr), that can be used as a guide for prescribing patients with the appropriate amount of iron. Patients, undergoing hemodialysis, were retrospectively selected from the database and were divided in two groups: group A received intravenous (IV) iron and subcutaneously ESA, and their dosages were adjusted on the basis of the following parameters: Hb, Mean corpuscular haemoglobin (MCH), CHr with consequent MCH/CHr ratio and reticulocyte count determined by the ADVIA 120 Hematology System of Siemens; group B patients were administered IV iron and ESA monitoring iron storage, Hb and ferritin. The aforementioned parameters and the administered amount of iron and ESA were monitored at baseline, four and eight months from the begining of the study. For ESA supplementation, no difference was observed between the groups at the various observed times. Despite similar Hb levels, the patients of group A needed significant lower doses of IV iron (-57.8%) avoiding risks of organ toxicity and obtaining consequent cost saving of nearly 1 €/patient/month. The use of CHr and its related parameters allows the avoidance of overdosage of IV iron, which can potentially damage organs, and the reduction of health care direct and indirect costs. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  2. Genetic and environmental relationships of metabolic and weight phenotypes to metabolic syndrome and diabetes: the healthy twin study.

    Science.gov (United States)

    Song, Yun-Mi; Sung, Joohon; Lee, Kayoung

    2015-02-01

    We aimed to examine the relationships, including genetic and environmental correlations, between metabolic and weight phenotypes and factors related to diabetes and metabolic syndrome. Participants of the Healthy Twin Study without diabetes (n=2687; 895 monozygotic and 204 dizygotic twins, and 1588 nontwin family members; mean age, 42.5±13.1 years) were stratified according to body mass index (BMI) (metabolic syndrome categories at baseline. The metabolic traits, namely diabetes and metabolic syndrome, metabolic syndrome components, glycated hemoglobin (HbA1c) level, and homeostasis model assessment of insulin resistance (HOMA-IR), were assessed after 2.5±2.1 years. In a multivariate-adjusted model, those who had metabolic syndrome or overweight phenotypes at baseline were more likely to have higher HbA1C and HOMA-IR levels and abnormal metabolic syndrome components at follow-up as compared to the metabolically healthy normal weight subgroup. The incidence of diabetes was 4.4-fold higher in the metabolically unhealthy but normal weight individuals and 3.3-fold higher in the metabolically unhealthy and overweight individuals as compared with the metabolically healthy normal weight individuals. The heritability of the metabolic syndrome/weight phenotypes was 0.40±0.03. Significant genetic and environmental correlations were observed between the metabolic syndrome/weight phenotypes at baseline and the metabolic traits at follow-up, except for incident diabetes, which only had a significant common genetic sharing with the baseline phenotypes. The genetic and environmental relationships between the metabolic and weight phenotypes at baseline and the metabolic traits at follow-up suggest pleiotropic genetic mechanisms and the crucial role of lifestyle and behavioral factors.

  3. Low iron stores are related to higher blood concentrations of manganese, cobalt and cadmium in non-smoking, Norwegian women in the HUNT 2 study

    Energy Technology Data Exchange (ETDEWEB)

    Margrete Meltzer, Helle, E-mail: helle.margrete.meltzer@fhi.no [Division of Environmental Medicine, Department of Food Safety and Nutrition, Norwegian Institute of Public Health, PO Box 4404 Nydalen, N-0403 Oslo (Norway); Lise Brantsaeter, Anne [Division of Environmental Medicine, Department of Food Safety and Nutrition, Norwegian Institute of Public Health, PO Box 4404 Nydalen, N-0403 Oslo (Norway); Borch-Iohnsen, Berit [Institute of Basic Medical Sciences, Department of Nutrition, University of Oslo, PO Box 1046 Blindern, N-0316 Oslo (Norway); Ellingsen, Dag G. [National Institute of Occupational Health, PO Box 8149 Dep, N-0033 Oslo (Norway); Alexander, Jan [Division of Environmental Medicine, Department of Food Safety and Nutrition, Norwegian Institute of Public Health, PO Box 4404 Nydalen, N-0403 Oslo (Norway); Thomassen, Yngvar [National Institute of Occupational Health, PO Box 8149 Dep, N-0033 Oslo (Norway); Stigum, Hein [Division of Epidemiology, Department of Chronic Diseases, Norwegian Institute of Public Health, PO Box 4404 Nydalen, N-0403 Oslo (Norway); Ydersbond, Trond A. [Statistics Norway, P.Box 8131 Dep, N-0033 Oslo (Norway)

    2010-07-15

    Low iron (Fe) stores may influence absorption or transport of divalent metals in blood. To obtain more knowledge about such associations, the divalent metal ions cadmium (Cd), manganese (Mn), cobalt (Co), copper (Cu), zinc (Zn) and lead (Pb) and parameters of Fe metabolism (serum ferritin, haemoglobin (Hb) and transferrin) were investigated in 448 healthy, menstruating non-smoking women, age 20-55 years (mean 38 years), participating in the Norwegian HUNT 2 study. The study population was stratified for serum ferritin: 257 were iron-depleted (serum ferritin <12 {mu}g/L) and 84 had iron deficiency anaemia (serum ferritin <12 {mu}g/L and Hb<120 g/L). The low ferritin group had increased blood concentrations of Mn, Co and Cd but normal concentrations of Cu, Zn and Pb. In multiple regression models, ferritin emerged as the main determinant of Mn, Co and Cd (p<0.001), while no significant associations with Cu, Zn and Pb were found. Adjusted r{sup 2} for the models were 0.28, 0.48 and 0.34, respectively. Strong positive associations between blood concentrations of Mn, Co and Cd were observed, also when controlled for their common association with ferritin. Apart from these associations, the models showed no significant interactions between the six divalent metals studied. Very mild anaemia (110{<=}Hb<120 g/L) did not seem to have any effect independent of low ferritin. Approximately 26% of the women with iron deficiency anaemia had high concentrations of all of Mn, Co and Cd as opposed to 2.3% of iron-replete subjects. The results confirm that low serum ferritin may have an impact on body kinetics of certain divalent metal ions, but not all. Only a fraction of women with low iron status exhibited an increased blood concentration of divalent metals, providing indication of complexities in the body's handling of these metals.

  4. Donation intensity and metabolic syndrome in active whole-blood donors

    NARCIS (Netherlands)

    Peffer, K.; Verbeek, A.L.M.; Swinkels, D.W.; Geurts-Moespot, A.J.; den Heijer, M.; Atsma, F.

    2015-01-01

    Background and Objectives: Increased iron and metabolic syndrome (MetS) go hand in hand. Frequent blood donation depletes iron stores. This study investigates whether high-intensity blood donation is associated with lower MetS prevalence compared with low-intensity blood donation, and whether iron

  5. Weekly iron folic acid supplementation plays differential role in maintaining iron markers level in non-anaemic and anaemic primigravida: A randomized controlled study

    Directory of Open Access Journals (Sweden)

    Hari Shankar

    2016-11-01

    Full Text Available Anaemia during pregnancy is most commonly observed and highly prevalent in South-East Asia. Various effective programmes have been laid down for its management, mainly daily supplementation of iron folic acid (IFA tablets. Following the same, standard obstetrical practice has included the IFA supplementation without requiring the determination of iron deficiency. In this study, a total of 120 primigravida (N = 60; non-anaemic (Hb > 11 g/dl and N = 60 anaemic (Hb = 8–11 g/dl were selected among those attending the Antenatal Clinic in Department of Obstetrics and Gynaecology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, India. They were supplemented with daily and weekly IFA tablets till 6 weeks postpartum. Corresponding changes in haemoglobin level on advance of pregnancy, side effects and compliance associated with daily and weekly IFA supplementation and its associations with iron status markers were studied. The inflammatory markers were also estimated. The statistical significance level (p < 0.05 between the groups were assessed by applying unpaired t-test using SPSS (version 16.0. The obtained results publicized the salutary role of daily IFA supplementation in improving the haemoglobin level and iron status markers in anaemic pregnant women though the levels could not reach up to the non-anaemic haemoglobin levels. However, weekly IFA supplementation seems to be a better approach in non-anaemic pregnant women where almost comparable results were obtained in terms of haematological parameters, gestation length and birth weight. Conclusion: Weekly IFA supplementation found to be as effective as daily supplementation in iron sufficient non-anaemic pregnant women whereas anaemic pregnant women should be prescribed daily IFA supplementation irrespective of iron replete/deplete state. Keywords: Anaemia, Iron folic acid supplementation, Iron status markers, Pregnancy

  6. Iron addiction: a novel therapeutic target in ovarian cancer

    International Nuclear Information System (INIS)

    Basuli, D.

    2017-01-01

    Ovarian cancer is a lethal malignancy that has not seen a major therapeutic advance in over 30 years. We demonstrate that ovarian cancer exhibits a targetable alteration in iron metabolism. Ferroportin (FPN), the iron efflux pump, is decreased, and transferrin receptor (TFR1), the iron importer, is increased in tumor tissue from patients with high grade but not low grade serous ovarian cancer. A similar profile of decreased FPN and increased TFR1 is observed in a genetic model of ovarian cancer tumor-initiating cells (TICs). The net result of these changes is an accumulation of excess intracellular iron and an augmented dependence on iron for proliferation. A forced reduction in intracellular iron reduces the proliferation of ovarian cancer TICs in vitro, and inhibits both tumor growth and intraperitoneal dissemination of tumor cells in vivo. Some mechanistic studies demonstrate that iron increases metastatic spread by facilitating invasion through expression of matrix metalloproteases and synthesis of interleukin 6 (IL-6). Here, we show that the iron dependence of ovarian cancer TICs renders them exquisitely sensitive in vivo to agents that induce iron-dependent cell death (ferroptosis) as well as iron chelators, and thus creates a metabolic vulnerability that can be exploited therapeutically.

  7. Moessbauer Study of Iron-Containing Carbon Nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Marco, J. F.; Gancedo, J. R. [CSIC, Instituto de Quimica-Fisica ' Rocasolano' (Spain); Hernando, A.; Crespo, P.; Prados, C.; Gonzalez, J. M. [Instituto de Magnetismo Aplicado (Spain); Grobert, N.; Terrones, M.; Walton, D. R. M.; Kroto, H. W. [University of Sussex, Fullerene Science Centre, School of Chemistry, Physics and Environmental Science (United Kingdom)

    2002-03-15

    {sup 57}Fe transmission Moessbauer at temperatures between 18 and 298 K and magnetic measurements have been used to characterize Fe-filled carbon nanotubes which were prepared by pyrolisis of Ferrocene + C{sub 60} at atmospheric pressure under an Ar atmosphere at 1050{sup o}C. The Moessbauer data have shown that the Fe phases encapsulated within the carbon nanotubes are {alpha}-Fe, Fe{sub 3}C and {gamma}-Fe. The magnetic results are compatible with the Moessbauer data. Taken together the results allow us to propose a simple picture of the distribution of iron phases within the carbon nanotubes which would consist of an {alpha}-Fe core surrounded by an {gamma}-Fe shell, finally covered by an Fe{sub 3}C layer.

  8. Study on Damage Mechanism of Ductile Cast Iron Cooling Stave

    Science.gov (United States)

    Wang, Cui; Zhang, Jianliang; Zuo, Haibin; Dai, Bing

    The damage mechanism of ductile cast iron cooling stave applied to No.4 blast furnace of Guofeng steel was analyzed through damage investigation in details, the damage causes: high-temperature gas flow erosion, wear of burden, high-temperature ablation, carburizing damage, improper operation on blast furnace, etc. were given out both in macroscopic and microscopic views. It can be obtained from metallographic diagrams that the diameter of graphite nodules increases, the number per unit area reduces, and roundness declines, successively, from cold to hot surface, which are not conducive to stave longevity. In summary, the material for staves manufacture should be better in comprehensive mechanical properties to prolong the service life, thus making blast furnace long campaign.

  9. Evidence that iron accelerates Alzheimer's pathology: a CSF biomarker study.

    Science.gov (United States)

    Ayton, Scott; Diouf, Ibrahima; Bush, Ashley Ian

    2018-05-01

    To investigate whether cerebrospinal fluid (CSF) ferritin (reporting brain iron) is associated with longitudinal changes in CSF β-amyloid (Aβ) and tau. Mixed-effects models of CSF Aβ 1-42 and tau were constructed using data from 296 participants who had baseline measurement of CSF ferritin and annual measurement of CSF tau and Aβ 1-42 for up to 5 years. In subjects with biomarker-confirmed Alzheimer's pathology, high CSF ferritin (>6.2 ng/mL) was associated with accelerated depreciation of CSF Aβ 1-42 (reporting increased plaque formation; p=0.0001). CSF ferritin was neither associated with changes in CSF tau in the same subjects, nor longitudinal changes in CSF tau or Aβ 1-42 in subjects with low baseline pathology. In simulation modelling of the natural history of Aβ deposition, which we estimated to occur over 31.4 years, we predicted that it would take 12.6 years to reach the pathology threshold value of CSF Aβ from healthy normal levels, and this interval is not affected by CSF ferritin. CSF ferritin influences the fall in CSF Aβ over the next phase, where high CSF ferritin accelerated the transition from threshold preclinical Aβ levels to the average level of Alzheimer's subjects from 18.8 to 10.8 years. Iron might facilitate Aβ deposition in Alzheimer's and accelerate the disease process. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  10. A Synchrotron Mössbauer Spectroscopy Study of a Hydrated Iron-Sulfate at High Pressures

    Science.gov (United States)

    Perez, T. M.; Finkelstein, G. J.; Solomatova, N. V.; Jackson, J. M.

    2017-12-01

    Szomolnokite is a monohydrated ferrous iron sulfate mineral, FeSO4*H2O, where the ferrous iron atoms are in octahedral coordination with four corners shared with SO4 and two with H2O. While somewhat rare on Earth, szomolnokite has been detected on the surface of Mars along with several other hydrated sulfates and suggested to occur near the surface of Venus [1,2]. It is not clear if these sulfates are a result of reactions occurring at depth driven by changes in the behavior of iron in the sulfate. To date, only a few high-pressure studies have been conducted on hydrated iron sulfates using Mössbauer spectroscopy. Our study represents a first step towards understanding of the electronic environment of iron in a monohydrated sulfate at pressure. Using a hydrostatic helium pressure-transmitting medium, the pressure dependence of iron's site-specific behavior in a synthetic szomolnokite powdered sample was explored up to about 100 GPa with time-resolved synchrotron Mössbauer spectroscopy at the Advanced Photon Source of Argonne National Laboratory. At 1 bar, the Mössbauer spectrum is well described by three Fe2+-like sites, consistent with conventional Mössbauer spectra reported in Dyar et al. [3]. At pressures up to 20 GPa, changes in the hyperfine parameters are most likely due to a structural phase transition. Above this pressure, a fourth site is required to explain the time-spectra. Changes in the electronic configuration of iron, such as those due to a phase transition and/or a spin crossover, will affect the material's compressibility and transport properties. We will compare our high-pressure trends with those of other iron-bearing phases and discuss the relative influence on the dynamics of terrestrial planetary interiors. 1. Bishop et al. (2014) What Lurks in the Martian Rocks and Soil? Investigations of Sulfates, Phosphates, and Perchlorates. Spectral and thermal properties of perchlorate salts and implications for Mars. Am. Min. 99(8-9), 1580

  11. Study of iron valence state and position in sub-site by Moessbauer spectroscopy

    International Nuclear Information System (INIS)

    Uhm, Young Rang; Lim, Jae Cheong; KIm, Chul Sung; Son, Kwang Jae

    2014-01-01

    The magnetic ordering temperature and the magnitude of the magnetic fields at the iron sites of YIG can be influenced by substituting, either partially or totally, the Fe 3+ ions at the octahedral and/or the tetrahedral sites with magnetic or diamagnetic ions, and/or by substitution the Y 3+ ions at the dodecahedral sites with magnetic rare earth ions. It has been known for some time that Moessbauer spectroscopy is a powerful method by which iron-containing garnets can be studied. We report here on the synthesis of the compounds with garnet-related structures of composition Y 3 Fe 4.5 Cr 0.5 O 12 and its examination by 57 Fe Moessbauer spectroscopy. The chromium in compounds of the Y 3 Fe 4.5 Cr 0.5 O 12 is distributed at an octahedral site. The Moessbauer spectra can be analyzed using 3 or 4 sets of six Lorentzians with increasing amount of Cr 3+ compounds in this system. It results from the distribution ( 4 C n ) of Fe 3+ and Cr 3+ at an octahedral site. A comparative study of ferrous tablets of Dynabi was carried out using Moessbauer spectroscopy. The obtained results revealed the presence of ferrous (Fe 2+ ) gluconate and ferrous fumarate in a sample. This observation is important to better control the iron state in such medicaments because their pharmaceutical effect in the body is related to the form and valence of iron. The Cr-containing yttrium iron garnet (YIG), and the exchange interactions and site distributions were studied using 57 Fe Moessbauer spectroscopy. The obtained results revealed the presence of ferrous (Fe 2+ ) gluconate and ferrous fumarate in the sample. This observation is important better control the iron state in such medicaments because their pharmaceutical effect in the body is related to the form and valence of iron

  12. Iron deficiency in childhood

    NARCIS (Netherlands)

    Uijterschout, L.

    2015-01-01

    Iron deficiency (ID) is the most common micronutrient deficiency in the world. Iron is involved in oxygen transport, energy metabolism, immune response, and plays an important role in brain development. In infancy, ID is associated with adverse effects on cognitive, motor, and behavioral development

  13. Iron(II)-Catalyzed Iron Atom Exchange and Mineralogical Changes in Iron-rich Organic Freshwater Flocs: An Iron Isotope Tracer Study.

    Science.gov (United States)

    ThomasArrigo, Laurel K; Mikutta, Christian; Byrne, James; Kappler, Andreas; Kretzschmar, Ruben

    2017-06-20

    In freshwater wetlands, organic flocs are often found enriched in trace metal(loid)s associated with poorly crystalline Fe(III)-(oxyhydr)oxides. Under reducing conditions, flocs may become exposed to aqueous Fe(II), triggering Fe(II)-catalyzed mineral transformations and trace metal(loid) release. In this study, pure ferrihydrite, a synthetic ferrihydrite-polygalacturonic acid coprecipitate (16.7 wt % C), and As- (1280 and 1230 mg/kg) and organic matter (OM)-rich (18.1 and 21.8 wt % C) freshwater flocs dominated by ferrihydrite and nanocrystalline lepidocrocite were reacted with an isotopically enriched 57 Fe(II) solution (0.1 or 1.0 mM Fe(II)) at pH 5.5 and 7. Using a combination of wet chemistry, Fe isotope analysis, X-ray absorption spectroscopy (XAS), 57 Fe Mössbauer spectroscopy and X-ray diffraction, we followed the Fe atom exchange kinetics and secondary mineral formation over 1 week. When reacted with Fe(II) at pH 7, pure ferrihydrite exhibited rapid Fe atom exchange at both Fe(II) concentrations, reaching 76 and 89% atom exchange in experiments with 0.1 and 1 mM Fe(II), respectively. XAS data revealed that it transformed into goethite (21%) at the lower Fe(II) concentration and into lepidocrocite (73%) and goethite (27%) at the higher Fe(II) concentration. Despite smaller Fe mineral particles in the coprecipitate and flocs as compared to pure ferrihydrite (inferred from Mössbauer-derived blocking temperatures), these samples showed reduced Fe atom exchange (9-30% at pH 7) and inhibited secondary mineral formation. No release of As was recorded for Fe(II)-reacted flocs. Our findings indicate that carbohydrate-rich OM in flocs stabilizes poorly crystalline Fe minerals against Fe(II)-catalyzed transformation by surface-site blockage and/or organic Fe(II) complexation. This hinders the extent of Fe atom exchange at mineral surfaces and secondary mineral formation, which may consequently impair Fe(II)-activated trace metal(loid) release. Thus, under short

  14. Macrophage function as studied by the clearance of 125I-labeled polyvinylpyrrolidone in iron-deficient and iron-replete mice

    International Nuclear Information System (INIS)

    Kuvibidila, S.; Wade, S.

    1987-01-01

    This study evaluated the effects of iron deficiency and iron repletion on in vivo macrophage function determined by the clearance of 125 I-labeled polyvinylpyrrolidone (PVP). Two experiments were done. There were four groups of C57BL/6 female mice in experiment 1: the iron-deficient (ID), pair-fed (PF), control (C) and the high iron (HI) groups. In experiment 2, there were three ID groups (severe to moderate anemia), three PF, one C and four ID groups that were fed adequate iron for 14 (R-14), 7 (R-7), 3 (R-3) days before or on the day of PVP injection (R-0). The overall rate of PVP clearance from blood was lower in ID than in C or PF groups. This clearance is expressed by a constant, K, calculated from natural log (ln) of the cpm and the time postadministration of PVP that blood was drawn. The theoretical individual macrophages function (alpha PVP), derived from K and the weights of body, spleen and liver, was also lower in ID than in C or PF groups. The impairment was most severe with the most severe iron deficiency. Repletion for 7 to 15 d before PVP administration resulted in a partial correction of the clearance. Moderate undernutrition in the PF group had no effect

  15. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... also are hoping to determine which iron supplements work best to treat iron-deficiency anemia in children who do not consume the daily recommended amount of iron. Read less Participate in NHLBI Clinical Trials We lead or sponsor many studies related to iron-deficiency anemia. See if you ...

  16. NMR-Metabolic Methodology in the Study of GM Foods

    Science.gov (United States)

    The 1H NMR methodology used in the study of genetically modified (GM) foodstuff is discussed. The study of transgenic lettuce (Lactuca sativa cv "Luxor") over-expressing the KNAT1 gene from Arabidopsis is presented as a novel study-case. The 1H NMR metabolic profiling was carried out. Twenty-two wat...

  17. Associations between single nucleotide polymorphisms in iron-related genes and iron status in multiethnic populations.

    Directory of Open Access Journals (Sweden)

    Christine E McLaren

    Full Text Available The existence of multiple inherited disorders of iron metabolism suggests genetic contributions to iron deficiency. We previously performed a genome-wide association study of iron-related single nucleotide polymorphisms (SNPs using DNA from white men aged ≥ 25 y and women ≥ 50 y in the Hemochromatosis and Iron Overload Screening (HEIRS Study with serum ferritin (SF ≤ 12 µg/L (cases and controls (SF >100 µg/L in men, SF >50 µg/L in women. We report a follow-up study of white, African-American, Hispanic, and Asian HEIRS participants, analyzed for association between SNPs and eight iron-related outcomes. Three chromosomal regions showed association across multiple populations, including SNPs in the TF and TMPRSS6 genes, and on chromosome 18q21. A novel SNP rs1421312 in TMPRSS6 was associated with serum iron in whites (p = 3.7 × 10(-6 and replicated in African Americans (p = 0.0012.Twenty SNPs in the TF gene region were associated with total iron-binding capacity in whites (p<4.4 × 10(-5; six SNPs replicated in other ethnicities (p<0.01. SNP rs10904850 in the CUBN gene on 10p13 was associated with serum iron in African Americans (P = 1.0 × 10(-5. These results confirm known associations with iron measures and give unique evidence of their role in different ethnicities, suggesting origins in a common founder.

  18. Fast reactor shield sensitivity studies for steel--sodium--iron systems

    International Nuclear Information System (INIS)

    Oblow, E.M.; Weisbin, C.R.

    1977-01-01

    A study was made of the adequacy of the current ENDF/B-IV sodium and iron neutron cross section data files for fast reactor shield design work. Experimental data from 21 fast reactor shield configurations containing large thicknesses of steel, sodium, and iron were analyzed with discrete ordinates calculations and sensitivity methods to assess the data files. This study represents the largest full-scale sensitivity analysis of benchmark quality experimental data to date. Included in the sensitivity studies were the results of the new cross section adjustment algorithms added to the FORSS code system. Conclusions were drawn about the need for more accurate data for sodium and iron elastic and discrete inelastic cross sections above 1 MeV and the values of the total cross section in the vicinity of important minima

  19. Current understanding of iron homeostasis.

    Science.gov (United States)

    Anderson, Gregory J; Frazer, David M

    2017-12-01

    Iron is an essential trace element, but it is also toxic in excess, and thus mammals have developed elegant mechanisms for keeping both cellular and whole-body iron concentrations within the optimal physiologic range. In the diet, iron is either sequestered within heme or in various nonheme forms. Although the absorption of heme iron is poorly understood, nonheme iron is transported across the apical membrane of the intestinal enterocyte by divalent metal-ion transporter 1 (DMT1) and is exported into the circulation via ferroportin 1 (FPN1). Newly absorbed iron binds to plasma transferrin and is distributed around the body to sites of utilization with the erythroid marrow having particularly high iron requirements. Iron-loaded transferrin binds to transferrin receptor 1 on the surface of most body cells, and after endocytosis of the complex, iron enters the cytoplasm via DMT1 in the endosomal membrane. This iron can be used for metabolic functions, stored within cytosolic ferritin, or exported from the cell via FPN1. Cellular iron concentrations are modulated by the iron regulatory proteins (IRPs) IRP1 and IRP2. At the whole-body level, dietary iron absorption and iron export from the tissues into the plasma are regulated by the liver-derived peptide hepcidin. When tissue iron demands are high, hepcidin concentrations are low and vice versa. Too little or too much iron can have important clinical consequences. Most iron deficiency reflects an inadequate supply of iron in the diet, whereas iron excess is usually associated with hereditary disorders. These disorders include various forms of hemochromatosis, which are characterized by inadequate hepcidin production and, thus, increased dietary iron intake, and iron-loading anemias whereby both increased iron absorption and transfusion therapy contribute to the iron overload. Despite major recent advances, much remains to be learned about iron physiology and pathophysiology. © 2017 American Society for Nutrition.

  20. A study on the formation of iron aluminide (FeAl) from elemental powders

    Energy Technology Data Exchange (ETDEWEB)

    Sina, H.; Corneliusson, J.; Turba, K.; Iyengar, S.

    2015-07-05

    Highlights: • Fe–40 at.% Al discs with coarse iron powder showed precombustion and combustion peaks. • Loose powder mixtures and discs with fine iron powder showed only combustion peaks. • Slower heating rate and fine aluminum particles promote precombustion. • The major product formed during both the reactions was Fe{sub 2}Al{sub 5}. • Heating the samples to 1000 °C yielded a stable FeAl phase as the final product. - Abstract: The formation of iron aluminide (FeAl) during the heating of Fe–40 at.% Al powder mixture has been studied using a differential scanning calorimeter. The effect of particle size of the reactants, compaction of the powder mixtures as well as the heating rate on combustion behavior has been investigated. On heating compacted discs containing relatively coarser iron powder, DSC data show two consecutive exothermic peaks corresponding to precombustion and combustion reactions. The product formed during both these reactions is Fe{sub 2}Al{sub 5} and there is a volume expansion in the sample. The precombustion reaction could be improved by a slower heating rate as well as a better surface coverage of iron particles using relatively finer aluminum powder. The combustion reaction was observed to be weaker after a strong precombustion stage. Heating the samples to 1000 °C resulted in the formation of a single and stable FeAl phase through the diffusional reaction between Fe{sub 2}Al{sub 5} and residual iron. DSC results for compacted discs containing relatively finer iron powder and for the non-compacted samples showed a single combustion exotherm during heating, with Fe{sub 2}Al{sub 5} as the product and traces of FeAl. X-ray diffraction and EDS data confirmed the formation of FeAl as the final product after heating these samples to 1000 °C.

  1. Identification of genes expressed by Cryptococcus gattii during iron deprivation

    Directory of Open Access Journals (Sweden)

    Daphine Ariadne Jesus de Paula

    2014-09-01

    Full Text Available Cryptococcus neoformans and C. gattii are pathogenic yeasts that cause life-threatening diseases in humans and animals. Iron is an essential nutrient for virtually every organism as it functions as a cofactor in numerous essential enzymatic reactions. In the literature, the competition for iron between microbes and mammalian hosts during infection is well documented. In this study, we used representational difference analysis (RDA in order to gain a better understanding of how C. gattii responds to iron starvation. A total of 15 and 29 genes were identified as having altered expression levels due to iron depletion after 3 h and 12 h, respectively. Of these, eight genes were identified in both libraries. The transcripts were related to many biological processes, such as cell cycle, ergosterol metabolism, cell wall organization, transportation, translation, cell respiration and the stress response. These data suggest a remodeling of C. gattii metabolism during conditions of iron deprivation.

  2. Cell membrane damage by iron nanoparticles: an invitro study

    Directory of Open Access Journals (Sweden)

    Gelare Hajsalimi

    2016-12-01

    Full Text Available Application of nanotechnology in medicinal and biological fields has attracted a great interest in the recent yeras. In this paper the cell membrane leakage induced by iron nanoparticles (Fe-NP against PC12 cell line which is known as a model of nervous system cell line was investigated by the lactate dehydrogenase (LDH test. Therefore, PC12 cells were incubated with different concentration of Fe-NP and test was performed after 48h of incubation of the cells with Fe-NP. The resulting data showed that the Fe-NP induced the damage of PC12 cell membrane in a concentration dependent manner. Hence, it may be concluded that the different cytotoxicty effect of NPs may be referred to the concentration of NPs, type of the NPs and the cells. Indeed, the kind of cytotoxic impacts of NPs on the cells can be reduced by the considering of above-mentioned parameters. The resulting data showed that the Fe-NP induced the damage of PC12 cell membrane in a concentration dependent manner. Hence, it may be concluded that the different cytotoxicty effect of NPs may be referred to the concentration of NPs, type of the NPs and the cells. Indeed, the kind of cytotoxic impacts of NPs on the cells can be reduced by the considering of above-mentioned parameters.

  3. SQUID biosusceptometry in the measurement of hepatic iron

    International Nuclear Information System (INIS)

    Sheth, Sujit

    2003-01-01

    Individuals with primary or secondary abnormalities of iron metabolism, such as hereditary hemochromatosis and transfusional iron loading, may develop potentially lethal systemic iron overload. Over time, this excess iron is progressively deposited in the liver, heart, pancreas, and other organs, resulting in cirrhosis, heart disease, diabetes and other disorders. Unless treated, death usually results from cardiac failure. The amount of iron in the liver is the best indicator of the amount of iron in the whole body. At present, the only sure way to measure the amount of iron in the liver is to remove a sample of the liver by biopsy. Iron stored in the liver can be magnetized to a small degree when placed in a magnetic field. The amount of magnetization is measured by our instrument, called a superconducting quantum interference device (SQUID) susceptometer. In patients with iron overload, our previous studies have shown that magnetic measurements of liver iron in patients with iron overload are quantitatively equivalent to biochemical determinations on tissue obtained by biopsy. The safety, ease, rapidity, and comfort of magnetic measurements make frequent, serial studies technically feasible and practically acceptable to patients. (orig.)

  4. Thermodynamic studies of chromium adsorption on iron species generated by electrocoagulation

    Energy Technology Data Exchange (ETDEWEB)

    Parga, J.R.; Vazquez, V.; Gonzalez, G.; Cisneros, M.M. [Metallurgy and Materials Science Department, Institute Technology of Saltillo (Mexico)

    2010-10-15

    The protection of the global environment and in particular, the provision of a sustainable source of clean water is a necessity for human survival. Specifically, large quantities of chromium containing compounds are being discharged into the environment. This study has been carried out to determine the feasibility of chromium adsorption on iron species by an Electrocoagulation (EC) process using the Langmuir Isotherm. The full potential of EC with air injection as an alternative wastewater treatment technique to remove chromium from well water shows more than 99 % removal without the addition of any chemical reagents. In this study, X-Ray Diffraction, Scanning Electron Microscopy, Moessbauer Spectroscopy and Fourier Transform Infrared Spectroscopy are used to characterize the solid products that reveal the expected crystalline iron oxides, i.e., lepidocrocite, magnetite, gohetite, and iron oxide. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  5. Studies of Actinides Reduction on Iron Surfaces by Means of Resonant Inelastic X-ray Scattering

    International Nuclear Information System (INIS)

    Kvashnina, K.O.; Butorin, S.M.; Shuh, D.K.; Ollila, K.; Soroka, I.; Guo, J.-H.; Werme, L.; Nordgren, J.

    2006-01-01

    The interaction of actinides with corroded iron surfaces was studied using resonant inelastic x-ray scattering (RIXS) spectroscopy at actinide 5d edges. RIXS profiles, corresponding to the f-f excitations are found to be very sensitive to the chemical states of actinides in different systems. Our results clearly indicate that U(VI) (as soluble uranyl ion) was reduced to U(IV) in the form of relatively insoluble uranium species, indicating that the iron presence significantly affects the mobility of actinides, creating reducing conditions. Also Np(V) and Pu (VI) in the ground water solution were getting reduced by the iron surface to Np(IV) and Pu (IV) respectively. Studying the reduction of actinides compounds will have an important process controlling the environmental behavior. Using RIXS we have shown that actinides, formed by radiolysis of water in the disposal canister, are likely to be reduced on the inset corrosion products and prevent release from the canister

  6. Wetting of Liquid Iron in Carbon Nanotubes and on Graphene Sheets: A Molecular Dynamics Study

    International Nuclear Information System (INIS)

    Gao Yu-Feng; Yang Yang; Sun De-Yan

    2011-01-01

    Using molecular dynamics simulations, we study the wetting of liquid iron in a carbon nanotube and on a graphene sheet. It is found that the contact angle of a droplet in a carbon nanotube increases linearly with the increase of wall curvature but is independent of the length of the filled liquid. The contact angle for a droplet on a graphene sheet decreases with the increasing droplet size. The line tension of a droplet on a graphene sheet is also obtained. Detailed studies show that liquid iron near the carbon walls exhibits the ordering tendencies in both the normal and tangential directions. (condensed matter: structure, mechanical and thermal properties)

  7. Pit morphology studies of iron and steel in alkaline chloride environment using EMPA technique

    International Nuclear Information System (INIS)

    Benjamin, S.E.; Sykes, J.M.

    1993-01-01

    A comparative study of iron and steel in stimulated alkaline chloride solutions showed that Swedish iron has better reproducibility in terms of pitting potentials as compared to ordinary hot rolled mild steel. This study was undertaken to reason this pitting behavior on the basis of number and the nature of inclusions present in both the metals. Electron probe microanalysis technique (EPMA) was utilised to contemplate the origin of pits, the solution chemistry of the pits and finally the nature of the rust product. (author)

  8. Studies in iodine metabolism: Progress report, July 1968-July 1969

    Energy Technology Data Exchange (ETDEWEB)

    Van Middlesworth, L.

    1987-01-01

    This document describes research on iodine metabolism conducted at the University of Tennessee, Memphis between July 1968 and July 1969. The author and his research team prepared autoradiographs of rat thyroids from individuals exposed to Iodine 125 in utero. Additional studies were conducted to determine the effect on hypothalamic lesions on iodide metabolism in rats; to evaluate an iodide-specific electrode for measuring iodide levels in blood or urine; and to study the amount of thyroxine absorption from the intestine. An analysis of bovine and sheep thyroids from eight locations provided additional information on global fallout levels. 21 figs., 2 tabs.

  9. Justice at work and metabolic syndrome: the Whitehall II study.

    Science.gov (United States)

    Gimeno, David; Tabák, Adám G; Ferrie, Jane E; Shipley, Martin J; De Vogli, Roberto; Elovainio, Marko; Vahtera, Jussi; Marmot, Michael G; Kivimäki, Mika

    2010-04-01

    Growing evidence shows that high levels of justice are beneficial for employee health, although biological mechanisms underlying this association are yet to be clarified. We aim to test whether high justice at work protects against metabolic syndrome. A prospective cohort study of 20 civil service departments in London (the Whitehall II study) including 6123 male and female British civil servants aged 35-55 years without prevalent coronary heart disease at baseline (1985-1990). Perceived justice at work was determined by means of questionnaire on two occasions between 1985 and 1990. Follow-up for metabolic syndrome and its components occurring from 1990 to 2004 was based on clinical assessments on three occasions over more than 18 years. Cox proportional hazard models adjusted for age, ethnicity and employment grade showed that men who experienced a high level of justice at work had a lower risk of incident metabolic syndrome than employees with a low level of justice (HR 0.75; 95% CI 0.63 to 0.89). There was little evidence of an association between organisational justice and metabolic syndrome or its components in women (HR 0.88; 95% CI 0.67 to 1.17). Our prospective findings provide evidence of an association between high levels of justice at work and the development of metabolic syndrome in men.

  10. Skeletal scintigraphy and quantitative tracer studies in metabolic bone disease

    Science.gov (United States)

    Fogelman, Ignac

    Bone scan imaging with the current bone seeking radiopharmaceuticals, the technetium-99m labelled diphosphonates, has dramatically improved our ability to evaluate skeletal pathology. In this thesis, chapter 1 presents a review of the history of bone scanning, summarises present concepts as to the mechanism of uptake of bone seeking agents and briefly illustrates the role of bone scanning in clinical practice. In chapter 2 the applications of bone scan imaging and quantitative tracer techniques derived from the bone scan in the detection of metabolic bone disease are discussed. Since skeletal uptake of Tc-99m diphosphonate depends upon skeletal metabolism one might expect that the bone scan would be of considerable value in the assessment of metabolic bone disease. However in these disorders the whole skeleton is often diffusely involved by the metabolic process and simple visual inspection of the scan image may not reveal the uniformly increased uptake of tracer. Certain patterns of bone scan abnormality have, however, been reported in patients with primary hyperparathyroidism and renal osteo-dystrophy; the present studies extend these observations and introduce the concept of "metabolic features" which are often recognisable in conditions with generalised increased bone turnover. As an aid to systematic recognition of these features on a given bone scan image a semi-quantitative scoring system, the metabolic index, was introduced. The metabolic index allowed differentiation between various groups of patients with metabolic disorders and a control population. In addition, in a bone scan study of patients with acromegaly, it was found that the metabolic index correlated well with disease activity as measured by serum growth hormone levels. The metabolic index was, however, found to be a relatively insensitive means of identifying disease in individual patients. Patients with increased bone turnover will have an absolute increase in skeletal uptake of tracer. As a

  11. Iron in typical and atypical parkinsonism – Mössbauer spectroscopy and MRI studies

    Energy Technology Data Exchange (ETDEWEB)

    Kuliński, R. [Bródno Hospital, MRI Lab (Poland); Bauminger, E. R. [Hebrew University, Racah Institute of Physics (Israel); Friedman, A. [Medical University of Warsaw, Department of Neurology (Poland); Duda, P.; Gałązka-Friedman, J., E-mail: jgfrie@if.pw.edu.pl [Warsaw University of Technology, Faculty of Physics (Poland)

    2016-12-15

    Iron may play important role in neurodegeneration. The results of comparative studies of human brain areas (control and pathological) performed by Mössbauer spectroscopy (MS) and magnetic resonance imaging (MRI) techniques are presented. Mössbauer spectroscopy demonstrated a higher concentration of iron in atypical parkinsonism (progressive supranuclear palsy PSP) in the brain areas Substantia Nigra (SN) and Globus Pallidus (GP) involved in this pathological process, compared to control, while the concentration of iron in pathological tissues in typical parkinsonism (Parkinson’s disease - PD) did not differ from that in control. These results were compared with the changes in 1/T1 and 1/T2 (T1 and T2 being the relaxation times determined by MRI). A good linear correlation curve was found between the concentration of iron as determined by MS in different areas of control human brains and between 1/T1 and 1/T2. Whereas the finding in PSP-GP (the brain area involved in PSP) also fitted to such a correlation, this was not so for the correlation between pathological SN – the brain area involved in both diseases – and 1/T2, indicating a dependence of T2 on other factors than just the concentration of iron.

  12. Study of iron exchanged zeolites by Moessbauer effect and electron spin resonance spectroscopy

    International Nuclear Information System (INIS)

    Aguirre Campuzano, C.E.

    1993-01-01

    Crystalline iron exchanged NaY zeolites, prepared from aqueous solutions and calcined at atmospheric conditions, have been studied and characterized by XRD, Moessbauer and EPR spectroscopies and TGA analysis. Three iron sites are clearly distinguished from Moessbauer and EPR measurements. Firstly, characteristic Moessbauer and EPR spectra may arise from framework sites, suggesting that Fe has substituted Al. It is also found that their spectroscopic signals are not intensity affected by thermal treatments. Secondly, a Moessbauer doublet which may arise from octahedral sites in the large cavity of the zeolite, shows however, that this doublet and its EPR signal are intensity temperature affected. An additional line broadening is observed on the low velocity line of this doublet, Thirdly, characteristic Moessbauer and EPR signals, which are also intensity temperature dependent have been associated to accluded material, where the Moessbauer doublet presents the line broadening effect before mentioned. Such line broadening effect may be due to perturbing signals from iron ions in tetrahedral sites. Finally, it has been observed that during calcination of the FeY zeolites, the three characteristic EPR signals for the three iron sites, do not increase at the expenses of the other. A result that may suggest a strong bonding between Fe-site of the Y zeolite, irrespective of the iron source. (Author)

  13. Mineralogical Study of Zard Koh and Kulli Koh Iron Ore Deposits of Pakistan

    Directory of Open Access Journals (Sweden)

    SULTAN AHMED KHOSO

    2017-10-01

    Full Text Available Zard Koh and Kulli Koh are two recently discovered iron ore deposits, existing in the Chagai district, Balochistan, Pakistan. PSM (Pakistan Steel Mill Limited is interested to utilize these ore deposits at priority. Purpose of the present study was to assess the mineralogy of the Zard Koh and Kulli Koh iron ore deposits, as it plays a vital role in the selection of an appropriate processing method. The mineralogical study of ore deposits was carried out by XRD (X-Ray Diffraction, XRF (X-Ray Fluorescence, SEM (Scanning Electron Microscope attached with EDS (Energy Dispersive Spectroscope and SM (Stereomicroscope techniques. Results indicated that the Zard Koh ore is mainly composed of 60.15% maghemite, 23.57% pyrite, 4.07% chlorite, 10.30% grossular and 1.65% admontite minerals. The chemical analysis revealed that Zard Koh iron ore contains an average of 54.27% Fe, 12.73% S, 8.70% Si, 3.07% Al, 4.07% Ca, and 2.16% Mg. Similarly, the mineralogical study of the Kulli Koh iron ore indicated that, ore is containing 51.16% hematite, 29.24% quartz, 8.89% dravite, and 8.76% kaolinite minerals. Elemental analysis of different samples indicated that Kulli Koh iron ore contains an average composition of 40.23% Fe, 20.67% Si, 3.44% Ca, 3.81% Al and 3.25% Mg. Mineralogical study of the Zard Koh and Kulli Koh iron ore deposits suggested that these ore deposits can be beneficiated costeffectively by using magnetic separation techniques.

  14. Mineralogical study of zard koh and kulli koh iron ore deposits of pakistan

    International Nuclear Information System (INIS)

    Khoso, S.A.; Abro, M.I.

    2017-01-01

    Zard Koh and Kulli Koh are two recently discovered iron ore deposits, existing in the Chagai district, Balochistan, Pakistan. PSM (Pakistan Steel Mill Limited) is interested to utilize these ore deposits at priority. Purpose of the present study was to assess the mineralogy of the Zard Koh and Kulli Koh iron ore deposits, as it plays a vital role in the selection of an appropriate processing method. The mineralogical study of ore deposits was carried out by XRD (X-Ray Diffraction), XRF (X-Ray Fluorescence), SEM (Scanning Electron Microscope) attached with EDS (Energy Dispersive Spectroscope) and SM (Stereomicroscope) techniques. Results indicated that the Zard Koh ore is mainly composed of 60.15% maghemite, 23.57% pyrite, 4.07% chlorite, 10.30% grossular and 1.65% admontite minerals. The chemical analysis revealed that Zard Koh iron ore contains an average of 54.27% Fe, 12.73% S, 8.70% Si, 3.07% Al, 4.07% Ca, and 2.16% Mg. Similarly, the mineralogical study of the Kulli Koh iron ore indicated that, ore is containing 51.16% hematite, 29.24% quartz, 8.89% dravite, and 8.76% kaolinite minerals. Elemental analysis of different samples indicated that Kulli Koh iron ore contains an average composition of 40.23% Fe, 20.67% Si, 3.44% Ca, 3.81% Al and 3.25% Mg. Mineralogical study of the Zard Koh and Kulli Koh iron ore deposits suggested that these ore deposits can be beneficiated costeffectively by using magnetic separation techniques. (author)

  15. Modeling human Coenzyme A synthase mutation in yeast reveals altered mitochondrial function, lipid content and iron metabolism

    Directory of Open Access Journals (Sweden)

    Camilla Ceccatelli Berti

    2015-04-01

    Full Text Available Mutations in nuclear genes associated with defective coenzyme A biosynthesis have been identified as responsible for some forms of neurodegeneration with brain iron accumulation (NBIA, namely PKAN and CoPAN. PKAN are defined by mutations in PANK2, encoding the pantothenate kinase 2 enzyme, that account for about 50% of cases of NBIA, whereas mutations in CoA synthase COASY have been recently reported as the second inborn error of CoA synthesis leading to CoPAN. As reported previously, yeast cells expressing the pathogenic mutation exhibited a temperature-sensitive growth defect in the absence of pantothenate and a reduced CoA content. Additional characterization revealed decreased oxygen consumption, reduced activities of mitochondrial respiratory complexes, higher iron content, increased sensitivity to oxidative stress and reduced amount of lipid droplets, thus partially recapitulating the phenotypes found in patients and establishing yeast as a potential model to clarify the pathogenesis underlying PKAN and CoPAN diseases.

  16. Radioactive Lysine in Protein Metabolism Studies

    Science.gov (United States)

    Miller, L. L.; Bale, W. F.; Yuile, C. L.; Masters, R. E.; Tishkoff, G. H.; Whipple,, G. H.

    1950-01-09

    Studies of incorporation of DL-lysine in various body proteins of the dog; the time course of labeled blood proteins; and apparent rate of disappearance of labeled plasma proteins for comparison of behavior of the plasma albumin and globulin fractions; shows more rapid turn over of globulin fraction.

  17. Moessbauer study of cobalt and iron in the cyanobacterium (blue green alga)

    International Nuclear Information System (INIS)

    Ambe, Shizuko

    1990-01-01

    Moessbauer emission and absorption studies have been performed on cobalt and iron in the cyanobacterium (blue-green alga). The Moessbauer spectrum of the cyanobacterium cultivated with 57 Co is decomposed into two doublets. The parameters of the major doublet are in good agreement with those of cyanocobalamin (vitamin B 12 ) labeled with 57 Co. The other minor doublet has parameters close to those of Fe(II) coordinated with six nitrogen atoms. These suggest that cobalt is used for the biosynthesis of vitamin B 12 or its analogs in the cyanobacterium. The spectra of the cyanobacterium grown with 57 Fe show that iron is in the high-spin trivalent state and possibly in the form of ferritin, iron storage protein. (orig.)

  18. Theoretical Studies of Aqueous Systems above 25 deg C. 2. The Iron - Water System

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, Derek

    1971-09-15

    A theoretical study of the iron-water system at elevated temperatures is reported. Values for the equilibrium constants for the principle reactions in the system up to 374 deg C, obtained by a method described previously, are given and equilibrium diagrams are presented that illustrate the results for 50, 150, 250 and 350 deg C. The results indicate that, among other things, the most important metal-bearing ions in the iron-water system at elevated temperatures are Fe(OH){sub 2}+, Fe(OH)+ and HFeO{sub 2}- The conditions for the stability of solid iron oxides are also examined. Finally, some limitations of the thermodynamic approach to corrosion problems are discussed briefly

  19. NMR studies of cerebral metabolism in vivo

    International Nuclear Information System (INIS)

    Prichard, J.W.

    1986-01-01

    The nature and extent of the potential synergism between PET and NMR methods is not yet well appreciated in the biomedical community. The long-range interest of medical neurobiology will be well served by efforts of PET and NMR scientists to follow each others' work so that opportunities for productive interchange can be efficiently exploited. Appreciation of the synergism by the rest of the biomedical community will follow naturally. PET is said by the people doing it to be still in its infancy, for they are more concerned with advancing their discipline than with admiring its already impressive achievements. On the scale of the same developmental metaphor, many NMR methods for studying the living human brain are still in utero. The best way to provide the reader a sense of the current status and future course of NMR research in medical neurobiology is by discussion of published in vivo studies. Such a discussion, adapted from another article is what follows

  20. Mapping and characterization of iron compounds in Alzheimer's tissue

    International Nuclear Information System (INIS)

    Collingwood, Joanna; Dobson, Jon

    2006-01-01

    Understanding the management of iron in the brain is of great importance in the study of neurodegeneration, where regional iron overload is frequently evident. A variety of approaches have been employed, from quantifying iron in various anatomical structures, to identifying genetic risk factors related to iron metabolism, and exploring chelation approaches to tackle iron overload in neurodegenerative disease. However, the ease with which iron can change valence state ensures that it is present in vivo in a wide variety of forms, both soluble and insoluble. Here, we review recent developments in approaches to locate and identify iron compounds in neurodegenerative tissue. In addition to complementary techniques that allow us to quantify and identify iron compounds using magnetometry, extraction, and electron microscopy, we are utilizing a powerful combined mapping/characterization approach with synchrotron X-rays. This has enabled the location and characterization of iron accumulations containing magnetite and ferritin in human Alzheimer's disease (AD) brain tissue sections in situ at micron-resolution. It is hoped that such approaches will contribute to our understanding of the role of unusual iron accumulations in disease pathogenesis, and optimise the potential to use brain iron as a clinical biomarker for early detection and diagnosis.

  1. Diffusion of iron in lithium niobate: a secondary ion mass spectrometry study

    Energy Technology Data Exchange (ETDEWEB)

    Ciampolillo, M.V.; Argiolas, N.; Zaltron, A.; Bazzan, M.; Sada, C. [University of Padova, Physics Department (Italy); CNISM, Padova (Italy)

    2011-10-15

    Iron-doped X-cut lithium niobate crystals were prepared by means of thermal diffusion from thin film varying in a systematic way the process parameters such as temperature and diffusion duration. Secondary Ion Mass Spectrometry was exploited to characterize the iron in-depth profiles. The evolution of the composition of the Fe thin film in the range between 600 C and 800 C was studied, and the diffusion coefficient at different temperatures in the range between 900 C and 1050 C and the activation energy of the diffusion process were estimated. (orig.)

  2. Pituitary gland levels of mercury, selenium, iron, and zinc in an Alzheimer`s disease study

    Energy Technology Data Exchange (ETDEWEB)

    Cornett, C.R.; Markesbery, W.R.; Wekstein, D.R.; Ehmann, W.D. [Univ. of Kentucky, Lexington, KY (United States)

    1996-12-31

    Mercury, iron, selenium, and zinc imbalances have been observed in comparisons between Alzheimer`s disease (AD) and control subject brains. Analyses of the pituitary gland have demonstrated that this organ retains relatively high concentrations of trace elements, including mercury, iron, and zinc. Our previous work has shown that the pituitary glands of AD and control subjects are typically higher in these trace elements than brain samples from the same subject. Instrumental neutron activation analysis (INAA) was used to compare the pituitary trace element levels of AD and control subjects. This study also describes the intrasubject relationships of brain trace element levels to those in the pituitary gland of AD and control subjects.

  3. Study of collagen metabolism after β radiation injury

    International Nuclear Information System (INIS)

    Zhou Yinghui; Xulan; Wu Shiliang; Zhang Xueguang; Chen Liesong

    2000-01-01

    Objective: To investigate the change of collagen metabolism and it's regulation after β radiation. Method: The animal model of β radiation injury was established by the β radiation produced by the linear accelerator; and irradiated NIH 3T3 cells were studied. In the experiment the contents of total collagen, collagen type I and type III were measured. The activity of MMPs-1 was tested. The contents of TGF-β 1 , IL-6 were also detected. Results: After exposure to β radiation, little change was found in the content of total collagen, but the content of collagen I decreased and the content of collagen III, MMPs-1 activity increased; the expression of TGF-β 1 , IL-6 increased. Conclusion: The changes in the metabolism of collagen play an important role in the irradiated injury of the skin; TGF-β 1 and IL-6 may be essential in the regulation of the collagen metabolism

  4. Sedimentary Sulphur:Iron Ratio Indicates Vivianite Occurrence: A Study from Two Contrasting Freshwater Systems.

    Directory of Open Access Journals (Sweden)

    Matthias Rothe

    Full Text Available An increasing number of studies constrain the importance of iron for the long-term retention of phosphorus (P under anoxic conditions, i.e. the formation of reduced iron phosphate minerals such as vivianite (Fe3(PO42⋅8H2O. Much remains unknown about vivianite formation, the factors controlling its occurrence, and its relevance for P burial during early sediment diagenesis. To study the occurrence of vivianite and to assess its relevance for P binding, surface sediments of two hydrologically contrasting waters were analysed by heavy-liquid separation and subsequent powder X-ray diffraction. In Lake Arendsee, vivianite was present in deeper sediment horizons and not in the uppermost layers with a sharp transition between vivianite and non-vivianite bearing layers. In contrast, in lowland river Lower Havel vivianite was present in the upper sediment layers and not in deeper horizons with a gradual transition between non-vivianite and vivianite bearing layers. In both waters, vivianite occurrence was accompanied by the presence of pyrite (FeS2. Vivianite formation was favoured by an elevated iron availability through a lower degree of sulphidisation and was present at a molar ratio of total sulphur to reactive iron smaller than 1.1, only. A longer lasting burden of sediments by organic matter, i.e. due to eutrophication, favours the release of sulphides, and the formation of insoluble iron sulphides leading to a lack of available iron and to less or no vivianite formation. This weakening in sedimentary P retention, representing a negative feedback mechanism (P release in terms of water quality, could be partly compensated by harmless Fe amendments.

  5. Obesity Promotes Alterations in Iron Recycling

    Directory of Open Access Journals (Sweden)

    Marta Citelli

    2015-01-01

    Full Text Available Hepcidin is a key hormone that induces the degradation of ferroportin (FPN, a protein that exports iron from reticuloendothelial macrophages and enterocytes. The aim of the present study was to experimentally evaluate if the obesity induced by a high-fat diet (HFD modifies the expression of FPN in macrophages and enterocytes, thus altering the iron bioavailability. In order to directly examine changes associated with iron metabolism in vivo, C57BL/6J mice were fed either a control or a HFD. Serum leptin levels were evaluated. The hepcidin, divalent metal transporter-1 (DMT1, FPN and ferritin genes were analyzed by real-time polymerase chain reaction. The amount of iron present in both the liver and spleen was determined by flame atomic absorption spectrometry. Ferroportin localization within reticuloendothelial macrophages was observed by immunofluorescence microscopy. Obese animals were found to exhibit increased hepcidin gene expression, while iron accumulated in the spleen and liver. They also exhibited changes in the sublocation of splenic cellular FPN and a reduction in the FPN expression in the liver and the spleen, while no changes were observed in enterocytes. Possible explanations for the increased hepcidin expression observed in HFD animals may include: increased leptin levels, the liver iron accumulation or endoplasmic reticulum (ER stress. Together, the results indicated that obesity promotes changes in iron bioavailability, since it altered the iron recycling function.

  6. Microbial processes in banded iron formation deposition

    DEFF Research Database (Denmark)

    Posth, Nicole; Konhauser, Kurt; Kappler, Andreas

    2013-01-01

    , remains unresolved. Evidence of an anoxic Earth with only localized oxic areas until the Great Oxidation Event ca 2·45 to 2·32 Ga makes the investigation of O2-independent mechanisms for banded iron formation deposition relevant. Recent studies have explored the long-standing proposition that Archean......Banded iron formations have been studied for decades, particularly regarding their potential as archives of the Precambrian environment. In spite of this effort, the mechanism of their deposition and, specifically, the role that microbes played in the precipitation of banded iron formation minerals...... banded iron formations may have been formed, and diagenetically modified, by anaerobic microbial metabolisms. These efforts encompass a wide array of approaches including isotope, ecophysiological and phylogeny studies, molecular and mineral marker analysis, and sedimentological reconstructions. Herein...

  7. Association of sleep quality components and wake time with metabolic syndrome: The Qazvin Metabolic Diseases Study (QMDS), Iran.

    Science.gov (United States)

    Zohal, Mohammadali; Ghorbani, Azam; Esmailzadehha, Neda; Ziaee, Amir; Mohammadi, Zahrasadat

    2017-11-01

    The aim of this study was to determine the association of sleep quality and sleep quantity with metabolic syndrome in Qazvin, Iran. this cross sectional study was conducted in 1079 residents of Qazvin selected by multistage cluster random sampling method in 2011. Metabolic syndrome was defined according to the criteria proposed by the national cholesterol education program third Adult treatment panel. Sleep was assessed using the Pittsburgh sleep quality index (PSQI). A logistic regression analysis was used to examine the association of sleep status and metabolic syndrome. Mean age was 40.08±10.33years. Of 1079, 578 (52.2%) were female, and 30.6% had metabolic syndrome. The total global PSQI score in the subjects with metabolic syndrome was significantly higher than subjects without metabolic syndrome (6.30±3.20 vs. 5.83±2.76, P=0.013). In logistic regression analysis, sleep disturbances was associated with 1.388 fold increased risk of metabolic syndrome after adjustment for age, gender, and body mass index. Sleep disturbances component was a predictor of metabolic syndrome in the present study. More longitudinal studies are necessary to understand the association of sleep quality and its components with metabolic syndrome. Copyright © 2017 Diabetes India. Published by Elsevier Ltd. All rights reserved.

  8. Iron absorption from beans with different contents of iron, evaluated by stable isotopes.

    Science.gov (United States)

    Junqueira-Franco, Márcia Varella Morandi; Dutra de Oliveira, José Eduardo; Nutti, Marilia Regini; Pereira, Helton Santos; Carvalho, José Luiz Vianna de; Abrams, Steven A; Brandão, Camila Fernanda Cunha; Marchini, Júlio Sérgio

    2018-06-01

    The introduction of biofortified foods such as beans with higher iron content may be a useful tool in preventing iron deficiency. The biofortification aims to reach the root of the problem of malnutrition, targets the neediest population, uses embedded distribution mechanisms, is scientifically feasible and effective in terms of cost, and complements other ongoing interventions to control micronutrient deficiency. However, to ensure effectiveness, measurement of the absorption of minerals is essential. The objective of this study was to evaluate the iron bioavailability of common bean BRS Pontal (PO), targeted for biofortification, compared with common bean BRS Estilo in man through reliable techniques that have not been previously used in Brazil. The study included 29 young adult volunteers divided into 2 groups: Group CB (13 subjects) received 100 g of common beans (BRS-Estilo) cooked labeled with iron-58 ( 58 Fe) and Group TBB (16 patients) received 100 g common bean target for iron biofortification (BRS-Pontal), cooked and labeled with iron58 ( 58 Fe). The next day they received the reference dose of ferrous sulfate enriched iron-57 ( 57 Fe). Isotopic evaluation of iron for measurement of iron incorporation into erythrocytes was performed 14 days after consumption. The beans used, were produced, through conventional breeding program, by EMBRAPA/Rice and Beans. The iron absorption was evaluated by assessing the isotopic enrichment of the stable isotope. Mean iron absorption from the meal with common beans was 0.409% (±0.040%) and mean iron incorporation from the meal with target beans for biofortification 0.407% (±0.038%) and did not differ between the groups. This study tested the iron absorption from a single bean meal in healthy volunteers or non anemics, In the present study the iron absorption ratio from common bean Pontal (PO), targeted for biofortification and compared with common bean BRS Estilo was not significantly different. The iron concentration

  9. CHARACTERIZATION OF METAL GRADES IN A STOCKPILE OF AN IRON MINE (CASE STUDY- CHOGHART IRON MINE, IRAN

    Directory of Open Access Journals (Sweden)

    Francesco Tinti

    2018-01-01

    Full Text Available In any mining operation due to the cut-off grade (economic criteria, materials classify into the ore and waste. The material with grade equal to or higher than the cut-off grade is considered as ore and the material with grade less than the cut-off grade is transported as wastes to the waste dumps. However, because of increasing metal demand, depleting of in situ ore reserves and so the reduction of cut-off grades for many metals, the mentioned waste dumps were considered as valuable ore reserves named stockpiles. In this paper, multivariate geostatistics was used to estimate the iron grades of two stockpiles following the sequential of piling procedures from the main source - the ore deposit - to the piling field. One stockpile is characterized by phosphorous concentration ((P % > 0.6 %, while the other by iron concentration ((Fe %< 50%. Since economic and physical constraints made sampling physically and economically problematic, the grade distribution and variability were estimated on the basis of primary blast-hole data from the main ore body and the mine’s long-term planning policy. A geostatistical model was applied to the excavated part of the iron deposit and the stockpile, by reconstructing ore selection, haulage and piling method. Results were validated through spatial variability of iron and phosphorous concentrations by comparing grade variability (Fe and P with mining and pilling units. This methodology allows characterizing the iron grades within stockpiles without any extra sampling.

  10. Mössbauer studies of iron doped poly(methyl methacrylate) before ...

    Indian Academy of Sciences (India)

    Unknown

    Mössbauer studies of iron doped poly(methyl methacrylate) before and after ion beam modification. D R S SOMAYAJULU, C N MURTHY†, D K AWASTHI‡, N V PATEL and M SARKAR. Physics Department, Faculty of Science, MS University of Baroda, Vadodara 390 002, India. †Applied Chemistry Department, Faculty ...

  11. A study of the levels of vanadium, cadmium, chromium and iron in ...

    African Journals Online (AJOL)

    Background: There is conflicting information on the adverse health effects of photocopier toner powder on operators.This study aims to determine the possible nephrotoxic effects of some commercially available photocopier toners and the levels of selected heavy metals (vanadium, cadmium, chromium and iron) for ...

  12. An electron-microscope study of alpha to gamma transformation in an iron-nickel alloy

    Science.gov (United States)

    Lobodyuk, V. A.; Khandros, L. G.; Fedas, N. P.

    1980-01-01

    Procedures used to study the alpha to gamma conversion in thin foils of an iron alloy with 32% nickel concentration and initial martensite conversion temperature of -60 C are described. Photomicrographs show deformation twinning as well as changes in samples after they were heated. Reverse conversion is discussed and results are examined.

  13. Ecological aspects of Moessbauer study of iron-containing atmospheric aerosols

    International Nuclear Information System (INIS)

    Kopcewicz, B.; Kopcewicz, M.

    2000-01-01

    Moessbauer spectroscopy was applied to analyze the iron compounds in atmospheric aerosol. Seasonal variations of iron concentration in atmospheric air measured over twenty years in Poland are discussed. It was observed that the concentration of iron sulfides (FeS, FeS 2 ) related to coal combustion dropped significantly, however, concentration of iron oxides and iron oxyhydroxides related to fuel combustion increased

  14. Research progress in role of iron overload in non-alcoholic fatty liver disease

    Directory of Open Access Journals (Sweden)

    LI Guangming

    2013-12-01

    Full Text Available Iron overload is an important research focus in non-alcoholic fatty liver disease (NAFLD. The relationship between iron overload and NAFLD is summarized from the assessment method for iron overload, relationship between iron load and hemochromatosis gene mutations, incidence of iron load in NAFLD, and relationship between iron load and progression of NAFLD; the action mechanism of iron overload in the progression of NAFLD is reviewed from the causes of iron overload, relationship between iron overload and lipid metabolism, and relationship between type of iron deposition and liver damage; the significance of iron overload in the diagnosis and treatment of NAFLD is discussed from iron overload as a new marker of risk stratification and potential therapeutic target in NAFLD. It is currently considered that iron overload, whether the cause or result of NAFLD progression, will promote the progression of NAFLD once it occurs; as a new marker of risk stratification and potential therapeutic target in NAFLD, iron load is worthy of further study.

  15. In vivo {sup 13}C MRS studies of carbohydrate metabolism

    Energy Technology Data Exchange (ETDEWEB)

    Halliday, Jane

    2003-07-01

    The work described in this thesis was performed by the author, except where indicated, within the Magnetic Resonance Centre at the University of Nottingham during the period between October 1999 and October 2002. Although much is known about the major pathways of carbohydrate metabolism, there is still much to be learnt about the exact mechanisms of many of these pathways. Of particular interest is how these pathways are modified under different physiological conditions and in diseased states. {sup 13}C NMR spectroscopy provides a non-invasive means for studying carbohydrate metabolism in vivo, and the work presented within this thesis gives two such examples of this in human subjects. Natural abundance {sup 13}C NMR spectroscopy was used to measure glycogen levels in gastrocnemius muscle. The diurnal changes in response to mixed meals were measured in both type 2 diabetic subjects and age and weight matched controls. Metabolic studies were performed to complement the NMR measurements. The data obtained in these studies show the effect of the failure of muscle glucose storage upon post-prandial hyperglycaemia despite a supra-normal increase in plasma insulin in type 2 diabetes. {sup 13}C NMR spectroscopy was also used to study cerebral metabolism. Accumulation of {sup 13}C label into glutamate and glutamine following infusion of [1{sup 13}C] glucose allows the determination of the rates of the TCA cycle (F{sub TCA}) and neurotransmitter cycling (F{sub cyc}). These rates were measured in the visual cortex under control and activated conditions. The increases seen in F{sub TCA} upon activation, together with the lack of label accumulation in lactate, suggest that cerebral glucose metabolism is oxidative, even during strong activation. No conclusion can be made as to whether or not a similar increase is seen in F{sub cyc} due to the large associated errors in these values. (author)

  16. In vivo 13C MRS studies of carbohydrate metabolism

    International Nuclear Information System (INIS)

    Halliday, Jane

    2003-01-01

    The work described in this thesis was performed by the author, except where indicated, within the Magnetic Resonance Centre at the University of Nottingham during the period between October 1999 and October 2002. Although much is known about the major pathways of carbohydrate metabolism, there is still much to be learnt about the exact mechanisms of many of these pathways. Of particular interest is how these pathways are modified under different physiological conditions and in diseased states. 13 C NMR spectroscopy provides a non-invasive means for studying carbohydrate metabolism in vivo, and the work presented within this thesis gives two such examples of this in human subjects. Natural abundance 13 C NMR spectroscopy was used to measure glycogen levels in gastrocnemius muscle. The diurnal changes in response to mixed meals were measured in both type 2 diabetic subjects and age and weight matched controls. Metabolic studies were performed to complement the NMR measurements. The data obtained in these studies show the effect of the failure of muscle glucose storage upon post-prandial hyperglycaemia despite a supra-normal increase in plasma insulin in type 2 diabetes. 13 C NMR spectroscopy was also used to study cerebral metabolism. Accumulation of 13 C label into glutamate and glutamine following infusion of [1 1 3 C] glucose allows the determination of the rates of the TCA cycle (F TCA ) and neurotransmitter cycling (F cyc ). These rates were measured in the visual cortex under control and activated conditions. The increases seen in F TCA upon activation, together with the lack of label accumulation in lactate, suggest that cerebral glucose metabolism is oxidative, even during strong activation. No conclusion can be made as to whether or not a similar increase is seen in F cyc due to the large associated errors in these values. (author)

  17. Snapshot of iron response in Shewanella oneidensis by gene network reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Yunfeng; Harris, Daniel P.; Luo, Feng; Xiong, Wenlu; Joachimiak, Marcin; Wu, Liyou; Dehal, Paramvir; Jacobsen, Janet; Yang, Zamin; Palumbo, Anthony V.; Arkin, Adam P.; Zhou, Jizhong

    2008-10-09

    Background: Iron homeostasis of Shewanella oneidensis, a gamma-proteobacterium possessing high iron content, is regulated by a global transcription factor Fur. However, knowledge is incomplete about other biological pathways that respond to changes in iron concentration, as well as details of the responses. In this work, we integrate physiological, transcriptomics and genetic approaches to delineate the iron response of S. oneidensis. Results: We show that the iron response in S. oneidensis is a rapid process. Temporal gene expression profiles were examined for iron depletion and repletion, and a gene co-expression network was reconstructed. Modules of iron acquisition systems, anaerobic energy metabolism and protein degradation were the most noteworthy in the gene network. Bioinformatics analyses suggested that genes in each of the modules might be regulated by DNA-binding proteins Fur, CRP and RpoH, respectively. Closer inspection of these modules revealed a transcriptional regulator (SO2426) involved in iron acquisition and ten transcriptional factors involved in anaerobic energy metabolism. Selected genes in the network were analyzed by genetic studies. Disruption of genes encoding a putative alcaligin biosynthesis protein (SO3032) and a gene previously implicated in protein degradation (SO2017) led to severe growth deficiency under iron depletion conditions. Disruption of a novel transcriptional factor (SO1415) caused deficiency in both anaerobic iron reduction and growth with thiosulfate or TMAO as an electronic acceptor, suggesting that SO1415 is required for specific branches of anaerobic energy metabolism pathways. Conclusions: Using a reconstructed gene network, we identified major biological pathways that were differentially expressed during iron depletion and repletion. Genetic studies not only demonstrated the importance of iron acquisition and protein degradation for iron depletion, but also characterized a novel transcriptional factor (SO1415) with a

  18. Adherence to iron supplements among women receiving antenatal care at Mulago National Referral Hospital, Uganda-cross-sectional study.

    Science.gov (United States)

    Kiwanuka, Tusuubira S; Ononge, Sam; Kiondo, Paul; Namusoke, Fatuma

    2017-10-25

    Antenatal iron supplementation is a cost effective way of reducing iron deficiency anaemia among pregnant women in resource limited countries like Uganda. Poor adherence to iron supplements has limited its effectiveness in reducing maternal anaemia as evidenced by the high burden of iron deficiency anemia in Sub-saharan Africa. The aim of this study was to determine the level of and factors associated with adherence to iron supplementation among women attending antenatal clinic at Mulago National Referral Hospital, Kampala, Uganda. Three hundred and seventy pregnant women were recruited in a cross sectional survey in Mulago National Referral Hospital antenatal clinic after informed consent between February and April 2014. Levels of adherence to iron supplements were assessed using visual analogue scale and factors associated collected using an interviewer administered questionnaire. About 12% (11.6%) of the mothers attending the antenatal clinic adhered to iron supplements over 30 day period. Mothers who had had four or more antenatal visits prior to the survey [odds ratio (OR) = 1.49, 95% confidence interval (CI) 1.12-1.97], had more than 2 week supply of iron supplements in the previous visit (OR 2.81, 95% CI 1.02-1.09), prior health education (OR 1.56, 95% CI 1.07-2.29) were more likely to adhere to iron supplements. Inadequate drug supplies and fear for side effects were the main reasons why participants missed the iron supplements. There was low adherence to iron supplements among mothers attending antenatal clinic at Mulago National Referral  Hospital. We recommend a national evaluation of adherence to iron supplements and look at ways of increasing adherence.

  19. Isotope-aided studies of the bioavailability of iron and zinc from human diets consumed in Poland

    International Nuclear Information System (INIS)

    Rafalski, H.; Switoniak, T.

    1994-01-01

    The bioavailability of food iron is affected by a number of physiological and dietary variables and it should be checked for the population living in natural conditions. The primary purpose of this study was to measure in volunteers iron absorption after oral administration of a wheat roll enriched with 15 mg of Fe as FeSO 4· 7H 2 O and 20 μCi of 59 Fe. For assessment of iron absorption whole body counting was used. The secondary purpose was to relate the available iron to iron stores, anthropometric indices, bleeding days and dietary variables. Thirteen female and 7 male healthy subjects aged between 19 and 47 years were observed. Hematological measurements on blood: serum ferritin (SF), serum iron (SI), total iron binding capacity (TIBC), transferrin (ST), transferrin saturation (TS), hemoglobin (Hb), hematocrit (Hct), red blood cell (RBC), mean corpuscular volume (MCV) were made. The subjects were examined by a specialist in internal medicine. Their 24-hour recall food intake was performed by questionnaire. The findings concerning the purposes of the study may be summarized as follows: 1) mean absorbed iron was 1.6 ± 1.2 mg for women, and 0.5±0.2 mg for men; 2) iron stores evaluated from SF were in women 2.6± 1.7 mg/kg body weight and in men 10.4±5.4 mg/kg; 3) blood indices proved iron deficiency anemia in 1 woman, Hb = 9.2 g/dL, SF = 1.8 μg/L, TS = 6%; in 4 women deficient iron stores were observed, Hb > 12g/dL, SF < 12 mg/L; 8 women and 7 men were normal; 4) in women the absorbed iron related inversely to SF (-0.61) and iron stores (-0.61); 5) the iron stores related to the sum of four skinfolds in women (0.55) and in men (0.80), in women it related to body weight (0.77) too; 6) in women the absorbed iron related to bleeding days (0.69); 7) in women ascorbic acid consumption related to iron store indices; SF, SI and TS. (author). 2 figs, 3 tabs

  20. Influence of food tannins on certain aspects of iron metabolism : Part 3 -- Heme synthesis and haematopoiesis in normal and anemic rats

    Energy Technology Data Exchange (ETDEWEB)

    Roy, S N [Albert Einstein Coll. of Medicine, Bronx, NY (USA); Mukherjee, S [Calcutta Univ. (India). Dept. of Applied Chemistry

    1979-06-01

    Tannin from various fruits and vegetables at a dose level of 0.5 mg/kg wt/day helps approximately 65% recovery of the blood hemoglobin concentration in hemolytic anemic rats within 7 days resulting in normal levels of haematological parameters. While in vitro tannin at low doses (5-10 ..mu..g/mg protein) stimulates iron incorporation into protoporphyrin IX by rat liver subcellular fractions, at higher doses (15-40 ..mu..g/mg protein) it inhibits the heme synthesis in liver, the inhibition being complete at 40 ..mu..g/mg protein. In vivo studies indicate that the administration of tannin (0.5 mg/kg) exhibits significant increase in incorporation of label into hemin of anemic rats compared to that of anemic control and tannin-fed normal groups. In rats receiving supplements of tannin (0.5 mg/k.o.), incorporation of the label into hemin of anemic ones is comparatively greater when /sup 59/Fe is given by intravenous route instead of oral administration of radio-iron. The total labelling of /sup 59/Fe in red blood cells is significantly greater in tannin-fed anemic rats than anemic control. These results suggest that tannin (0.5 mg/kg) from fruits and vegetables may help iron utilization more effectively for greater haematopoiesis in hemolytic anemia.

  1. Influence of food tannins on certain aspects of iron metabolism : Part 3 -- Heme synthesis and haematopoiesis in normal and anemic rats

    International Nuclear Information System (INIS)

    Roy, S.N.; Mukherjee, S.

    1979-01-01

    Tannin from various fruits and vegetables at a dose level of 0.5 mg/kg wt/day helps approximately 65% recovery of the blood hemoglobin concentration in hemolytic anemic rats within 7 days resulting in normal levels of haematological parameters. While in vitro tannin at low doses (5-10 μg/mg protein) stimulates iron incorporation into protoporphyrin IX by rat liver subcellular fractions, at higher doses (15-40 μg/mg protein) it inhibits the heme synthesis in liver, the inhibition being complete at 40 μg/mg protein. In vivo studies indicate that the administration of tannin (0.5 mg/kg) exhibits significant increase in incorporation of label into hemin of anemic rats compared to that of anemic control and tannin-fed normal groups. In rats receiving supplements of tannin (0.5 mg/k.o.), incorporation of the label into hemin of anemic ones is comparatively greater when 59 Fe is given by intravenous route instead of oral administration of radio-iron. The total labelling of 59 Fe in red blood cells is significantly greater in tannin-fed anemic rats than anemic control. These results suggest that tannin (0.5 mg/kg) from fruits and vegetables may help iron utilization more effectively for greater haematopoiesis in hemolytic anemia. (auth.)

  2. Structural studies on iron-tellurite glasses prepared by sol-gel method

    Energy Technology Data Exchange (ETDEWEB)

    Rada, S., E-mail: Simona.Rada@phys.utcluj.r [Department of Physics, Technical University of Cluj-Napoca, Bibliotecii, No. 10, 400020 Cluj-Napoca (Romania); Dehelean, A. [Department of Physics, Technical University of Cluj-Napoca, Bibliotecii, No. 10, 400020 Cluj-Napoca (Romania); Nat. Inst. for R and D of Isotopic and Molec. Technologies, Cluj-Napoca (Romania); Stan, M. [Nat. Inst. for R and D of Isotopic and Molec. Technologies, Cluj-Napoca (Romania); Chelcea, R. [Department of Physics, Technical University of Cluj-Napoca, Bibliotecii, No. 10, 400020 Cluj-Napoca (Romania); Nat. Inst. for R and D of Isotopic and Molec. Technologies, Cluj-Napoca (Romania); Culea, E. [Department of Physics, Technical University of Cluj-Napoca, Bibliotecii, No. 10, 400020 Cluj-Napoca (Romania)

    2011-01-05

    Research highlights: {yields} Iron-tellurite glasses obtained using the sol-gel synthesis. - Abstract: In this study, we report structural properties of the iron-tellurite glasses obtained using the sol-gel synthesis. The samples were characterized by X-ray diffraction, FTIR, UV-vis and EPR spectroscopy. Our results indicate dominant presence of iron ions in the trivalent state and the existence some Fe{sup 2+} ions. The analysis of the IR spectra indicates a gradual transformation of iron ions from tetrahedral into octahedral sites when the concentration of Fe(NO{sub 3}){sub 3} is increased beyond 0.64 mol%. EPR studies show that the increase of Fe(NO{sub 3}){sub 3} content in the host matrix induces the growth of the number of effective g values. This can be explained considering that the orbitals of O{sup 2-} ion with a large spin-orbit interaction constant will interact with the 3d orbital of Fe{sup 3+} ion bonded to this O{sup 2-} ion, thus leading to appearance of an orbital angular momentum which contributes to the magnetic moment of Fe{sup 3+} ion. A strong dipolar interaction, which is more predominant in a glass with higher content of Fe(NO{sub 3}){sub 3}, causing a localized magnetic field along the site of the Fe{sup 3+} ions and the increase the effective g values.

  3. An experimental study on MR lymphography with various iron colloid agents

    Energy Technology Data Exchange (ETDEWEB)

    Okuhata, Yoshitaka (Nihon Univ., Tokyo (Japan). School of Medicine)

    1992-08-01

    Magnetic resonance (MR) lymphography with iron colloid agents was evaluated in an animal model. The agents examined were ferric gluconate (FeG), saccharated ferric oxide (SFO), iron chondroitin sulfate (ICS) and cideferron (CiF), which were used as intravenous medication for iron deficiency anemia. The author performed time-dose-response and correlative histologic studies. MR images of the popliteal lymph nodes of rabbits were obtained at 1.5 T with a spin-echo sequence (TR=300, TE=30 msec) before and after subcutaneous injection of the agents to dorsal hind-feet. The images were evaluated by signal intensity (SI). Histologic specimens were evaluated for distribution and relative quantity of stained iron with a color image analyzer. The SI with FeG 4 mgFe increased by 50% at 5 to 60 minutes after injection but returned to the pre-contrast level 48 hours later. The SIs with SFO 8 mgFe, ICS 1 mgFe and CiF 1 mgFe decreased to the background level at 60 minutes and 48 hours after injection. The histologic study in combination with the images indicated that in case of FeG the particles in lymph increased SI while in the other agents those within macrophages decreased SI. Because the agents are already used clinically, they can be safety applied to MR lymphography. (author).

  4. FY 1990 Study Meeting of Catalyst (Iron system). Data; 1990 nendo shokubai kento kai (Tetsu kei) shiryo

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1991-03-01

    The FY 1990 Study Meeting of Iron-system Catalyst was held at NEDO on March 12, 1991, and the data were arranged. In the study meeting, papers titled as follows were made public: About the behavior of H{sub 2}S on iron-system catalyst by Muroran Institute of Technology; Results of the test on iron-system catalyst in the BCL project by Research Institute, Mitsubishi Kasei Corp.; Results of the test on iron-system catalyst by 2.4 t/d PDU by NKK; Results of the test on iron-system catalyst by 0.1 t/d BSU by Mitsui Engineering and Shipbuilding Co.; Results of the test on iron-system catalyst by 1 t/d PSU by Nippon Steel Corp.; Results of the research at Government Industrial Development Laboratory, Hokkaido, and the study; Results of the research at National Chemical Laboratory for Industry and the study; Results of the research at the University of Tokyo and the study; Details of the development of synthetic iron sulfide and the attainment up to now by Asahi Chemical Industry Co. Moreover, the plenary session was held on research items for the development of iron-system catalyst in future. (NEDO)

  5. Monocyte transferrin-iron uptake in hereditary hemochromatosis

    International Nuclear Information System (INIS)

    Sizemore, D.J.; Bassett, M.L.

    1984-01-01

    Transferrin-iron uptake by peripheral blood monocytes was studied in vitro to test the hypothesis that the relative paucity of mononuclear phagocyte iron loading in hereditary hemochromatosis results from a defect in uptake of iron from transferrin. Monocytes from nine control subjects and 17 patients with hemochromatosis were cultured in the presence of 59Fe-labelled human transferrin. There was no difference in 59Fe uptake between monocytes from control subjects and monocytes from patients with hemochromatosis who had been treated by phlebotomy and who had normal body iron stores. However, 59Fe uptake by monocytes from iron-loaded patients with hemochromatosis was significantly reduced compared with either control subjects or treated hemochromatosis patients. It is likely that this was a secondary effect of iron loading since iron uptake by monocytes from treated hemochromatosis patients was normal. Assuming that monocytes in culture reflect mononuclear phagocyte iron metabolism in vivo, this study suggests that the relative paucity of mononuclear phagocyte iron loading in hemochromatosis is not related to an abnormality in transferrin-iron uptake by these cells

  6. Nuclear magnetic resonance studies of epithelial metabolism and function

    International Nuclear Information System (INIS)

    Balaban, R.S.

    1982-01-01

    Nuclear magnetic resonance (NMR) is a noninvasive technique for studying cellular metabolism and function. In this review the general applications and advantages of NMR will be discussed with specific reference to epithelial tissues. Phosphorus NMR investigations have been performed on epithelial tissues in vivo and in vitro; however, other detectable nuclei have not been utilized to date. Several new applications of phosphorus NMR to epithelial tissues are also discussed, including studies on isolated renal tubules and sheet epithelia

  7. Study of iron valence state and position in sub-site by Moessbauer spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Uhm, Young Rang; Lim, Jae Cheong; KIm, Chul Sung [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Son, Kwang Jae [Kookmin Univ., Seoul (Korea, Republic of)

    2014-05-15

    The magnetic ordering temperature and the magnitude of the magnetic fields at the iron sites of YIG can be influenced by substituting, either partially or totally, the Fe{sup 3+} ions at the octahedral and/or the tetrahedral sites with magnetic or diamagnetic ions, and/or by substitution the Y{sup 3+} ions at the dodecahedral sites with magnetic rare earth ions. It has been known for some time that Moessbauer spectroscopy is a powerful method by which iron-containing garnets can be studied. We report here on the synthesis of the compounds with garnet-related structures of composition Y{sub 3}Fe{sub 4.5}Cr{sub 0.5}O{sub 12} and its examination by {sup 57}Fe Moessbauer spectroscopy. The chromium in compounds of the Y{sub 3}Fe{sub 4.5}Cr{sub 0.5}O{sub 12} is distributed at an octahedral site. The Moessbauer spectra can be analyzed using 3 or 4 sets of six Lorentzians with increasing amount of Cr{sup 3+} compounds in this system. It results from the distribution ({sub 4}C{sub n}) of Fe{sup 3+} and Cr{sup 3+} at an octahedral site. A comparative study of ferrous tablets of Dynabi was carried out using Moessbauer spectroscopy. The obtained results revealed the presence of ferrous (Fe{sup 2+}) gluconate and ferrous fumarate in a sample. This observation is important to better control the iron state in such medicaments because their pharmaceutical effect in the body is related to the form and valence of iron. The Cr-containing yttrium iron garnet (YIG), and the exchange interactions and site distributions were studied using {sup 57}Fe Moessbauer spectroscopy. The obtained results revealed the presence of ferrous (Fe{sup 2+}) gluconate and ferrous fumarate in the sample. This observation is important better control the iron state in such medicaments because their pharmaceutical effect in the body is related to the form and valence of iron.

  8. Metabolic studies in older mentally retarded patients: significance of metabolic testing and correlation with the clinical phenotype.

    NARCIS (Netherlands)

    Buggenhout, G.J.C.M. van; Trijbels, J.M.F.; Wevers, R.A.; Trommelen, J.C.M.; Hamel, B.C.J.; Brunner, H.G.; Fryns, J.P.

    2001-01-01

    In 471 adult mentally retarded adult patients (mean age 46 years; 92.6% males) living in an institution for the mentally retarded, a clinical examination, cytogenetic and molecular studies were done. 306 patients were screened for metabolic disorders. In 7 additional patients a metabolic disorder

  9. Moessbauer effect study of oxidation and coordination states of iron in some sodium borate glasse:;

    International Nuclear Information System (INIS)

    Eissa, N.A.; Sanad, A.M.; Youssef, S.M.; El-Henawii, S.A.; Gomaa, S.Sh.; Mostafa, A.G.

    1980-01-01

    A structural study of some sodium borate glasses containing iron was carried out applying ME spectroscopy. Both oxidation and coordination states of iron were investigated under the effect of gradual replacing of sodium carbonate by sodium nitrate in the glass batches. The glasses were melted in porcelain crucibles using an electrically heated furnace at 1000+-10 deg C, then were quenched on a steel plate at room temperature (R.T.). The ME source was 20 mCi radioactive Co-57 in chromium. The obtained ME spectra indicated that at lower sodium nitrate content both Fe 2+ and Fe 3+ are present in these glasses. At moderate concentrations some Fe 3+ ions were separated in a crystalline phase and the rest of the iron ions appeared as ferric ions in glassy state. At high sodium nitrate content only Fe 3+ ions in glassy state were detected. The values of the ME parameters for all iron ions indicated that all of them are in the octahedral coordination state. The density measurements confirm the separation of a crystalline phase at moderate sodium nitrate content. (author)

  10. Study of archaeological iron objects by PGAA, Mössbauer spectroscopy and X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, F. E., E-mail: fwagner@tum.de [Technische Universität München, Physik- Department E15 (Germany); Gebhard, R. [Archäologische Staatssammlung München (Germany); Häusler, W.; Wagner, U. [Technische Universität München, Physik- Department E15 (Germany); Albert, P.; Hess, H. [Archäologische Staatssammlung München (Germany); Révay, Z.; Kudejová, P.; Kleszcz, K. [Technische Universität München, Forschungsneutronenquelle Heinz Maier-Leibnitz (FRM II) (Germany)

    2016-12-15

    Archaeological iron objects often corrode rapidly after their excavation, even though they have survived long times of burial in the ground. Chlorine that accumulates during burial is thought to play a major role in this destructive post-excavation corrosion. It is therefore important for the conservation of such objects to determine the chlorine content in a non-destructive manner and, if necessary, to remove the chlorine from the artefacts by appropriate methods. Such methods are leaching in alkaline solutions or heating in a reducing atmosphere at temperatures up to 800 {sup ∘}C. We have studied the efficiency of the heating method using prompt gamma activation analysis (PGAA) for monitoring the Cl content and Mössbauer spectroscopy at room temperature (RT) and 4.2 K as well as X-ray diffraction to study the mineralogical transformations of the rust layers. The heat treatments were performed a N{sub 2}/H{sub 2} (90/10) mixture at temperatures up to 750 {sup ∘}C. As test specimens sections of iron rods from the Celtic oppidum of Manching (Bavaria) were used. The initial Cl contents of the pieces varied in the range of several hundred ppm, referring to the iron mass. Annealing for 24 h at 350, 550 and 750 {sup ∘}C was found to reduce the Cl contents of the specimens, to about 70, 30 and 15 % of the original values, respectively. The rust consists mainly of goethite with admixtures of magnetite, lepidocrocite and akaganeite, which is thought to be a major carrier of chlorine, probably together with iron chlorides. Much of the goethite is so fine-grained that it does not split magnetically at RT. Annealing converts the rust mainly to maghemite at 350 {sup ∘}C, to magnetite at 550 {sup ∘}C and to wüstite plus magnetite and metallic iron at 750 {sup ∘}C. Pure akaganeite behaves in nearly the same manner.

  11. Study of archaeological iron objects by PGAA, Mössbauer spectroscopy and X-ray diffraction

    International Nuclear Information System (INIS)

    Wagner, F. E.; Gebhard, R.; Häusler, W.; Wagner, U.; Albert, P.; Hess, H.; Révay, Z.; Kudejová, P.; Kleszcz, K.

    2016-01-01

    Archaeological iron objects often corrode rapidly after their excavation, even though they have survived long times of burial in the ground. Chlorine that accumulates during burial is thought to play a major role in this destructive post-excavation corrosion. It is therefore important for the conservation of such objects to determine the chlorine content in a non-destructive manner and, if necessary, to remove the chlorine from the artefacts by appropriate methods. Such methods are leaching in alkaline solutions or heating in a reducing atmosphere at temperatures up to 800 "∘C. We have studied the efficiency of the heating method using prompt gamma activation analysis (PGAA) for monitoring the Cl content and Mössbauer spectroscopy at room temperature (RT) and 4.2 K as well as X-ray diffraction to study the mineralogical transformations of the rust layers. The heat treatments were performed a N_2/H_2 (90/10) mixture at temperatures up to 750 "∘C. As test specimens sections of iron rods from the Celtic oppidum of Manching (Bavaria) were used. The initial Cl contents of the pieces varied in the range of several hundred ppm, referring to the iron mass. Annealing for 24 h at 350, 550 and 750 "∘C was found to reduce the Cl contents of the specimens, to about 70, 30 and 15 % of the original values, respectively. The rust consists mainly of goethite with admixtures of magnetite, lepidocrocite and akaganeite, which is thought to be a major carrier of chlorine, probably together with iron chlorides. Much of the goethite is so fine-grained that it does not split magnetically at RT. Annealing converts the rust mainly to maghemite at 350 "∘C, to magnetite at 550 "∘C and to wüstite plus magnetite and metallic iron at 750 "∘C. Pure akaganeite behaves in nearly the same manner.

  12. Quantitative Susceptibility Mapping Indicates a Disturbed Brain Iron Homeostasis in Neuromyelitis Optica - A Pilot Study.

    Directory of Open Access Journals (Sweden)

    Thomas Martin Doring

    Full Text Available Dysregulation of brain iron homeostasis is a hallmark of many neurodegenerative diseases and can be associated with oxidative stress. The objective of this study was to investigate brain iron in patients with Neuromyelitis Optica (NMO using quantitative susceptibility mapping (QSM, a quantitative iron-sensitive MRI technique. 12 clinically confirmed NMO patients (6 female and 6 male; age 35.4y±14.2y and 12 age- and sex-matched healthy controls (7 female and 5 male; age 33.9±11.3y underwent MRI of the brain at 3 Tesla. Quantitative maps of the effective transverse relaxation rate (R2* and magnetic susceptibility were calculated and a blinded ROI-based group comparison analysis was performed. Normality of the data and differences between patients and controls were tested by Kolmogorov-Smirnov and t-test, respectively. Correlation with age was studied using Spearman's rank correlation and an ANCOVA-like analysis. Magnetic susceptibility values were decreased in the red nucleus (p0.95; between -15 and -22 ppb depending on reference region with a trend toward increasing differences with age. R2* revealed significantly decreased relaxation in the optic radiations of five of the 12 patients (p<0.0001; -3.136±0.567 s-1. Decreased relaxation in the optic radiation is indicative for demyelination, which is in line with previous findings. Decreased magnetic susceptibility in the red nucleus is indicative for a lower brain iron concentration, a chemical redistribution of iron into less magnetic forms, or both. Further investigations are necessary to elucidate the pathological cause or consequence of this finding.

  13. Study of archaeological iron objects by PGAA, Mössbauer spectroscopy and X-ray diffraction

    Science.gov (United States)

    Wagner, F. E.; Gebhard, R.; Häusler, W.; Wagner, U.; Albert, P.; Hess, H.; Révay, Z.; Kudejová, P.; Kleszcz, K.

    2016-12-01

    Archaeological iron objects often corrode rapidly after their excavation, even though they have survived long times of burial in the ground. Chlorine that accumulates during burial is thought to play a major role in this destructive post-excavation corrosion. It is therefore important for the conservation of such objects to determine the chlorine content in a non-destructive manner and, if necessary, to remove the chlorine from the artefacts by appropriate methods. Such methods are leaching in alkaline solutions or heating in a reducing atmosphere at temperatures up to 800 ∘C. We have studied the efficiency of the heating method using prompt gamma activation analysis (PGAA) for monitoring the Cl content and Mössbauer spectroscopy at room temperature (RT) and 4.2 K as well as X-ray diffraction to study the mineralogical transformations of the rust layers. The heat treatments were performed a N2/H2 (90/10) mixture at temperatures up to 750 ∘C. As test specimens sections of iron rods from the Celtic oppidum of Manching (Bavaria) were used. The initial Cl contents of the pieces varied in the range of several hundred ppm, referring to the iron mass. Annealing for 24 h at 350, 550 and 750 ∘C was found to reduce the Cl contents of the specimens, to about 70, 30 and 15 % of the original values, respectively. The rust consists mainly of goethite with admixtures of magnetite, lepidocrocite and akaganeite, which is thought to be a major carrier of chlorine, probably together with iron chlorides. Much of the goethite is so fine-grained that it does not split magnetically at RT. Annealing converts the rust mainly to maghemite at 350 ∘C, to magnetite at 550 ∘C and to wüstite plus magnetite and metallic iron at 750 ∘C. Pure akaganeite behaves in nearly the same manner.

  14. CD/MCD/VTVH-MCD Studies of Escherichia coli Bacterioferritin Support a Binuclear Iron Cofactor Site.

    Science.gov (United States)

    Kwak, Yeonju; Schwartz, Jennifer K; Huang, Victor W; Boice, Emily; Kurtz, Donald M; Solomon, Edward I

    2015-12-01

    Ferritins and bacterioferritins (Bfrs) utilize a binuclear non-heme iron binding site to catalyze oxidation of Fe(II), leading to formation of an iron mineral core within a protein shell. Unlike ferritins, in which the diiron site binds Fe(II) as a substrate, which then autoxidizes and migrates to the mineral core, the diiron site in Bfr has a 2-His/4-carboxylate ligand set that is commonly found in diiron cofactor enzymes. Bfrs could, therefore, utilize the diiron site as a cofactor rather than for substrate iron binding. In this study, we applied circular dichroism (CD), magnetic CD (MCD), and variable-temperature, variable-field MCD (VTVH-MCD) spectroscopies to define the geometric and electronic structures of the biferrous active site in Escherichia coli Bfr. For these studies, we used an engineered M52L variant, which is known to eliminate binding of a heme cofactor but to have very minor effects on either iron oxidation or mineral core formation. We also examined an H46A/D50A/M52L Bfr variant, which additionally disrupts a previously observed mononuclear non-heme iron binding site inside the protein shell. The spectral analyses define a binuclear and an additional mononuclear ferrous site. The biferrous site shows two different five-coordinate centers. After O2 oxidation and re-reduction, only the mononuclear ferrous signal is eliminated. The retention of the biferrous but not the mononuclear ferrous site upon O2 cycling supports a mechanism in which the binuclear site acts as a cofactor for the O2 reaction, while the mononuclear site binds the substrate Fe(II) that, after its oxidation to Fe(III), migrates to the mineral core.

  15. Iron(II) porphyrins induced conversion of nitrite into nitric oxide: A computational study.

    Science.gov (United States)

    Zhang, Ting Ting; Liu, Yong Dong; Zhong, Ru Gang

    2015-09-01

    Nitrite reduction to nitric oxide by heme proteins was reported as a protective mechanism to hypoxic injury in mammalian physiology. In this study, the pathways of nitrite reduction to nitric oxide mediated by iron(II) porphyrin (P) complexes, which were generally recognized as models for heme proteins, were investigated by using density functional theory (DFT). In view of two type isomers of combination of nitrite and Fe(II)(P), N-nitro- and O-nitrito-Fe(II)-porphyrin complexes, and two binding sites of proton to the different O atoms of nitrite moiety, four main pathways for the conversion of nitrite into nitric oxide mediated by iron(II) porphyrins were proposed. The results indicate that the pathway of N-bound Fe(II)(P)(NO2) isomer into Fe(III)(P)(NO) and water is similar to that of O-bound isomer into nitric oxide and Fe(III)(P)(OH) in both thermodynamical and dynamical aspects. Based on the initial computational studies of five-coordinate nitrite complexes, the conversion of nitrite into NO mediated by Fe(II)(P)(L) complexes with 14 kinds of proximal ligands was also investigated. Generally, the same conclusion that the pathways of N-bound isomers are similar to those of O-bound isomer was obtained for iron(II) porphyrin with ligands. Different effects of ligands on the reduction reactions were also found. It is notable that the negative proximal ligands can improve reactive abilities of N-nitro-iron(II) porphyrins in the conversion of nitrite into nitric oxide compared to neutral ligands. The findings will be helpful to expand our understanding of the mechanism of nitrite reduction to nitric oxide by iron(II) porphyrins. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Metabolic and inflammatory profiles of biomarkers in obesity, metabolic syndrome, and diabetes in a Mediterranean population. DARIOS Inflammatory study.

    Science.gov (United States)

    Fernández-Bergés, Daniel; Consuegra-Sánchez, Luciano; Peñafiel, Judith; Cabrera de León, Antonio; Vila, Joan; Félix-Redondo, Francisco Javier; Segura-Fragoso, Antonio; Lapetra, José; Guembe, María Jesús; Vega, Tomás; Fitó, Montse; Elosua, Roberto; Díaz, Oscar; Marrugat, Jaume

    2014-08-01

    There is a paucity of data regarding the differences in the biomarker profiles of patients with obesity, metabolic syndrome, and diabetes mellitus as compared to a healthy, normal weight population. We aimed to study the biomarker profile of the metabolic risk continuum defined by the transition from normal weight to obesity, metabolic syndrome, and diabetes mellitus. We performed a pooled analysis of data from 7 cross-sectional Spanish population-based surveys. An extensive panel comprising 20 biomarkers related to carbohydrate metabolism, lipids, inflammation, coagulation, oxidation, hemodynamics, and myocardial damage was analyzed. We employed age- and sex-adjusted multinomial logistic regression models for the identification of those biomarkers associated with the metabolic risk continuum phenotypes: obesity, metabolic syndrome, and diabetes mellitus. A total of 2851 subjects were included for analyses. The mean age was 57.4 (8.8) years, 1269 were men (44.5%), and 464 participants were obese, 443 had metabolic syndrome, 473 had diabetes mellitus, and 1471 had a normal weight (healthy individuals). High-sensitivity C-reactive protein, apolipoprotein B100, leptin, and insulin were positively associated with at least one of the phenotypes of interest. Apolipoprotein A1 and adiponectin were negatively associated. There are differences between the population with normal weight and that having metabolic syndrome or diabetes with respect to certain biomarkers related to the metabolic, inflammatory, and lipid profiles. The results of this study support the relevance of these mechanisms in the metabolic risk continuum. When metabolic syndrome and diabetes mellitus are compared, these differences are less marked. Copyright © 2013 Sociedad Española de Cardiología. Published by Elsevier Espana. All rights reserved.

  17. Application of radioisotopes to studies of pesticide metabolism

    International Nuclear Information System (INIS)

    Shishido, Takashi

    1977-01-01

    Metabolic form and structural change of pesticides in the living body were mentioned. In the early stage of the study, 14 C, 35 S, 36 Cl, and 32 P were used, and 32 P was used mainly. At present, specimen labelled with 14 C or 3 H can be traced easily with liquid scintillation counter, and metabolic study is performed by using gaschromatography, nuclear magnetism resonant together with mass, and infrared spectrum analysis. Generally, pesticides are fat-soluble compounds. They convert into water-soluble compounds through the changes such as oxidation, reduction, and hydrolysis. Furthermore, they combine with ingredients in the living body, and are taken in. In animals, they are excreted outside the body, and in plants, they are stored after detoxication. Microorganisms break molecules into parts. They are used as energy source, and perform oxidative cleavage of nucleus of aromatic pesticides. (Kanao, N.)

  18. NMR-Metabolic Methodology in the Study of GM Foods

    Directory of Open Access Journals (Sweden)

    Irene D’Amico

    2010-01-01

    Full Text Available The 1H-NMR methodology used in the study of genetically modified (GM foods is discussed. Transgenic lettuce (Lactuca sativa cv "Luxor" over-expressing the Arabidopsis KNAT1 gene is presented as a case study. Twenty-two water-soluble metabolites (amino acids, organic acids, sugars present in leaves of conventional and GM lettuce were monitored by NMR and quantified at two developmental stages. The NMR spectra did not reveal any difference in metabolite composition between the GM lettuce and the wild type counterpart. Statistical analyses of metabolite variables highlighted metabolism variation as a function of leaf development as well as the transgene. A main effect of the transgene was in altering sugar metabolism.

  19. Novel mode of microbial energy metabolism: organic carbon oxidation coupled to dissimilatory reduction of iron or manganese.

    Science.gov (United States)

    Lovley, D R; Phillips, E J

    1988-06-01

    A dissimilatory Fe(III)- and Mn(IV)-reducing microorganism was isolated from freshwater sediments of the Potomac River, Maryland. The isolate, designated GS-15, grew in defined anaerobic medium with acetate as the sole electron donor and Fe(III), Mn(IV), or nitrate as the sole electron acceptor. GS-15 oxidized acetate to carbon dioxide with the concomitant reduction of amorphic Fe(III) oxide to magnetite (Fe(3)O(4)). When Fe(III) citrate replaced amorphic Fe(III) oxide as the electron acceptor, GS-15 grew faster and reduced all of the added Fe(III) to Fe(II). GS-15 reduced a natural amorphic Fe(III) oxide but did not significantly reduce highly crystalline Fe(III) forms. Fe(III) was reduced optimally at pH 6.7 to 7 and at 30 to 35 degrees C. Ethanol, butyrate, and propionate could also serve as electron donors for Fe(III) reduction. A variety of other organic compounds and hydrogen could not. MnO(2) was completely reduced to Mn(II), which precipitated as rhodochrosite (MnCO(3)). Nitrate was reduced to ammonia. Oxygen could not serve as an electron acceptor, and it inhibited growth with the other electron acceptors. This is the first demonstration that microorganisms can completely oxidize organic compounds with Fe(III) or Mn(IV) as the sole electron acceptor and that oxidation of organic matter coupled to dissimilatory Fe(III) or Mn(IV) reduction can yield energy for microbial growth. GS-15 provides a model for how enzymatically catalyzed reactions can be quantitatively significant mechanisms for the reduction of iron and manganese in anaerobic environments.

  20. Quantitative assessment of iron load in myocardial overload rabbit model: preliminary study of MRI T2* map

    International Nuclear Information System (INIS)

    Huang Lu; Han Rui; Li Zhiwei; Yuan Sishu; Xia Liming

    2014-01-01

    Objective: To preliminarily investigate the feasibility of MRI-T 2 * map in evaluating myocardial iron load of myocardial iron overload rabbit models. Methods: Eleven rabbits were included in this study and divided into two groups, myocardial iron overload group (n =10) and the control group (n = 1). Iron dextrin (dose of 50 mg/kg) was injected in muscles of thigh once a week, totally 12 weeks. Serum iron test and MRI examination were performed before iron injection,and 1 week to 12 weeks after iron injection. MRI scan protocol included short axial T 2 * map of the left ventricle and cross-section T 2 * map of the liver. T 2 * and R 2 * of the heart and the liver were measured. One rabbit was killed after MRI examination at pre-iron injection, 1 week to 8 weeks, 11 weeks and 12 weeks after iron injection,respectively. Heart and liver were avulsed to undergo in vitro MRI scan and then paraffin embedded for pathological slices. MRI scan protocol and measurements of the heart and the liver samples were the same to that of in vivo ones. Pearson correlation was used to calculate the relationships between the parameters. Results: Myocardial T 2 * [(32.5 ± 8.3 ms)] and R 2 * values [(38.4 ± 7.9) Hz] had significant correlation with injecting iron content (1033.2 ± 673.4 mg), the Pearson coefficients were -0.799 (P = 0.001) and 0.770 (P = 0.002), respectively. Myocardial T 2 * had no significant correlation with liver T 2 * values (r = 0.556, P = 0.070). T 2 * values of heart and liver in vivo [(32.5 ± 8.3) ms and (8.8 ± 5.4) ms], respectively had strong correlation with those in vitro [(19.4 ± 6.5) ms and (9.8 ± 5.0) ms], respectively (r = 0.757, P = 0.007 and r = 0.861, P = 0.001). T 2 * and R 2 * values of the heart and the liver in vivo and in vitro had no significant correlations with serum iron (P>0.05). On Prussian blue staining slices,blue particles of myocardium, sinus hepaticas and hepatocyte increased with injecting iron content. Conclusions: It is

  1. Iron intakes and status of 2-year-old children in the Cork BASELINE Birth Cohort Study.

    Science.gov (United States)

    McCarthy, Elaine K; Ní Chaoimh, Carol; Hourihane, Jonathan O'B; Kenny, Louise C; Irvine, Alan D; Murray, Deirdre M; Kiely, Mairead

    2017-07-01

    Young children are at risk of iron deficiency and subsequent anaemia, resulting in long-term consequences for cognitive, motor and behavioural development. This study aimed to describe the iron intakes, status and determinants of status in 2-year-old children. Data were collected prospectively in the mother-child Cork BASELINE Birth Cohort Study from 15 weeks' gestation throughout early childhood. At the 24-month assessment, serum ferritin, haemoglobin and mean corpuscular volume were measured, and food/nutrient intake data were collected using a 2-day weighed food diary. Iron status was assessed in 729 children (median [IQR] age: 2.1 [2.1, 2.2] years) and 468 completed a food diary. From the food diary, mean (SD) iron intakes were 6.8 (2.6) mg/day and 30% had intakes < UK Estimated Average Requirement (5.3 mg/day). Using WHO definitions, iron deficiency was observed in 4.6% (n = 31) and iron deficiency anaemia in five children (1.0%). Following an iron series workup, five more children were diagnosed with iron deficiency anaemia. Twenty-one per cent had ferritin concentrations <15 µg/L. Inadequate iron intakes (OR [95% CI]: 1.94 [1.09, 3.48]) and unmodified cows' milk intakes ≥ 400 mL/day (1.95 [1.07, 3.56]) increased the risk of low iron status. Iron-fortified formula consumption was associated with decreased risk (0.21 [0.11, 0.41] P < 0.05). In this, the largest study in toddlers in Europe, a lower prevalence of low iron status was observed than in previous reports. Compliance with dietary recommendations to limit cows' milk intakes in young children and consumption of iron-fortified products appears to have contributed to improved iron status at two years. © 2016 John Wiley & Sons Ltd.

  2. Pentachlorophenol dechlorination with zero valent iron: a Raman and GCMS study of the complex role of surficial iron oxides.

    Science.gov (United States)

    Gunawardana, Buddhika; Swedlund, Peter J; Singhal, Naresh; Nieuwoudt, Michel K

    2018-04-20

    The dechlorination of chlorinated organic pollutants by zero valent iron (ZVI) is an important water treatment process with a complex dependence on many variables. This complexity means that there are reported inconsistencies in terms of dechlorination with ZVI and the effect of ZVI acid treatment, which are significant and are as yet unexplained. This study aims to decipher some of this complexity by combining Raman spectroscopy with gas chromatography-mass spectrometry (GC-MS) to investigate the influence of the mineralogy of the iron oxide phases on the surface of ZVI on the reductive dechlorination of pentachlorophenol (PCP). Two electrolytic iron samples (ZVI-T and ZVI-H) were found to have quite different PCP dechlorination reactivity in batch reactors under anoxic conditions. Raman analysis of the "as-received" ZVI-T indicated the iron was mainly covered with the ferrous oxide (FeO) wustite, which is non-conducting and led to a low rate of PCP dechlorination. In contrast, the dominant oxide on the "as-received" ZVI-H was magnetite which is conducting and, compared to ZVI-T, the ZVI-H rate of PCP dechlorination was four times faster. Treating the ZVI-H sample with 1 N H 2 SO 4 made small change to the composition of the oxide layers and also minute change to the rate of PCP dechlorination. However, treating the ZVI-T sample with H 2 SO 4 led to the loss of wustite so that magnetite became the dominant oxide and the rate of PCP dechlorination increased to that of the ZVI-H material. In conclusion, this study clearly shows that iron oxide mineralogy can be a contributing factor to apparent inconsistencies in the literature related to ZVI performance towards dechlorination and the effect of acid treatment on ZVI reactivity.

  3. Study of collagen metabolism and regulation after β radiation injury

    International Nuclear Information System (INIS)

    Zhou Yinghui; Xu Lan; Wu Shiliang; Qiu Hao; Jiang Zhi; Tu Youbin; Zhang Xueguang

    2001-01-01

    The animal model of β radiation injury was established by the β radiation produced by the linear accelerator; and irradiated NIH 3T3 cells were studied. In the experiment the contents of total collagen, collagen type I and type III were measured. The activity of MMPs-1 were tested. The contents of TGF-β 1 , IL-6 were also detected. The results showed that after exposure to β radiation, little change was found in the content of total collagen, but the content of collagen I decreased and the content of collagen III, MMPs-1 activity increased; the expression of TGF-β 1 , IL-6 increased. The results suggest that changes in the metabolism of collagen play an important role in the irradiated injury of the skin; TGF-β 1 , IL-6 may be essential in the regulation of the collagen metabolism

  4. Study of collagen metabolism and regulation after {beta} radiation injury

    Energy Technology Data Exchange (ETDEWEB)

    Yinghui, Zhou; Lan, Xu; Shiliang, Wu; Hao, Qiu; Zhi, Jiang; Youbin, Tu; Xueguang, Zhang [Suzhou Medical College (China)

    2001-04-01

    The animal model of {beta} radiation injury was established by the {beta} radiation produced by the linear accelerator; and irradiated NIH 3T3 cells were studied. In the experiment the contents of total collagen, collagen type I and type III were measured. The activity of MMPs-1 were tested. The contents of TGF-{beta}{sub 1}, IL-6 were also detected. The results showed that after exposure to {beta} radiation, little change was found in the content of total collagen, but the content of collagen I decreased and the content of collagen III, MMPs-1 activity increased; the expression of TGF-{beta}{sub 1}, IL-6 increased. The results suggest that changes in the metabolism of collagen play an important role in the irradiated injury of the skin; TGF-{beta}{sub 1}, IL-6 may be essential in the regulation of the collagen metabolism.

  5. Morphologic study of the effect of iron on pseudocyst formation in Trichomonas vaginalis and its interaction with human epithelial cells.

    Science.gov (United States)

    Dias-Lopes, Geovane; Saboia-Vahia, Leonardo; Margotti, Eliane Trindade; Fernandes, Nilma de Souza; Castro, Cássia Luana de Faria; Oliveira, Francisco Odencio; Peixoto, Juliana Figueiredo; Britto, Constança; Silva, Fernando Costa E; Cuervo, Patricia; Jesus, José Batista de

    2017-10-01

    Trichomonas vaginalis is the aetiological agent of human trichomoniasis, which is one of the most prevalent sexually transmitted diseases in humans. Iron is an important element for the survival of this parasite and the colonisation of the host urogenital tract. In this study, we investigated the effects of iron on parasite proliferation in the dynamics of pseudocyst formation and morphologically characterised iron depletion-induced pseudocysts. We performed structural and ultrastructural analyses using light microscopy, scanning electron microscopy and transmission electron microscopy. It was observed that iron depletion (i) interrupts the proliferation of T. vaginalis, (ii) induces morphological changes in typical multiplicative trophozoites to spherical non-proliferative, non-motile pseudocysts, and (iii) induces the arrest of cell division at different stages of the cell cycle; (iv) iron is the fundamental element for the maintenance of typical trophozoite morphology; (v) pseudocysts induced by iron depletion are viable and reversible forms; and, finally, (vi) we demonstrated that pseudocysts induced by iron depletion are able to interact with human epithelial cells maintaining their spherical forms. Together, these data suggest that pseudocysts could be induced as a response to iron nutritional stress and could have a potential role in the transmission and infection of T. vaginalis.

  6. Utilization Patterns of IV Iron and Erythropoiesis Stimulating Agents in Anemic Chronic Kidney Disease Patients: A Multihospital Study

    Directory of Open Access Journals (Sweden)

    Avani D. Joshi

    2012-01-01

    Full Text Available Intravenous (IV iron and Erythropoiesis Stimulating Agents (ESAs are recommended for anemia management in chronic kidney disease (CKD. This retrospective cohort study analyzed utilization patterns of IV iron and ESA in patients over 18 years of age admitted to University Health System Hospitals with a primary or secondary diagnosis of CKD between January 1, 2006 to December 31, 2008. A clustered binomial logistic regression using the GEE methodology was used to identify predictors of IV iron utilization. Only 8% (n = 6678 of CKD patients on ESA therapy received IV iron supplementation in university hospitals. Those receiving iron used significantly less amounts of ESAs. Patient demographics (age, race, primary payer, patient clinical conditions (admission status, severity of illness, dialysis status, and physician specialty were identified as predictors of IV iron use in CKD patients. Use of IV iron with ESAs was low despite recommendations from consensus guidelines. The low treatment rate of IV iron represents a gap in treatment practices and signals an opportunity for healthcare improvement in CKD anemic patients.

  7. An observational study on the association of nonalcoholic fatty liver disease and metabolic syndrome with gall stone disease requiring cholecystectomy.

    Science.gov (United States)

    Ahmed, Farah; Baloch, Qamaruddin; Memon, Zahid Ali; Ali, Iqra

    2017-05-01

    Recognition of Non alcoholic fatty liver disease (NAFLD) and metabolic syndrome in patients with gallstones undergoing laparoscopic or open cholecystectomy, along with it we will also study the life style of patients with gall stones. Patients with gallstones have associated NAFLD, with concurrent metabolic syndrome and these ailments share similar factors for example obesity, hypertriglyceridemia and diabetes mellitus. Factors like body mass index, gender, raised lipid levels, use of contraceptives and alcohol and having diabetes, physical inactiveness, multiparous women, water with excessive iron content, metabolic syndrome, and NAFLD are accountable factors for gallstones formation. This was a case series done at Surgical Unit 1 of Civil Hospital Karachi. Selective samples of 88 patients were included. Duration was 3 months. We included both sexes with ultrasound proof of gall stone irrespective of cholecystitis. Excluded patients with history of seropositive viral hepatitis, autoimmune and wilson's disease. As these conditions can act as a confounder to our variables. Nafld was present in 62.5%(n = 55) while 28.4% (n = 25) had metabolic syndrome. 26.94% had BMI less than 18, 32.12 had BMI between 18 and 25 and majority had BMI greater than 25 i.e in 40.93%. Of all 46.6% had a family history of cholelithiasis. Gallstone patients with NAFLD reported about their fir