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1

Effects of experimental hemosiderosis on intestinal morphology, permeability, and tissue iron content.  

PubMed

Effects of iron overload on intestinal function and structure are unknown and were, therefore, investigated. Sprague-Dawley rats were randomized into an iron-overloaded group, which received a single subcutaneous injection of 1.2 g/kg elemental iron-dextran complex, and placebo-treated pair-fed controls. Animals were studied after a 10-month observation period. Intestinal permeability was assessed by measuring the urinary excretion of lactulose, rhamnose, and mannitol after oral administration. In addition, tissue nonheme iron content was measured, and histologic examination and morphometric measurements were carried out. The chronic iron-overloaded group showed a significant increase in intestine tissue iron content and stainable iron in the submucosa and muscularis propria and adipose tissue of the small intestine and lamina propria and muscularis mucosa of the large intestine. There was a significant decrease in the crypt depths without discernible change in the intestine permeability to any of the markers used. In addition, the iron-overloaded animals showed a significant number of iron-laden cells, which primarily consisted of macrophages, fibroblasts, myocytes, and adipocytes. In contrast, no iron-laden cells were present in tissues obtained from the normal control group. Thus, chronic experimental iron overload in rats leads to significant morphologic, but no permeability, alterations of the alimentary tract. PMID:8625773

Meshkinpour, H; Vaziri, N D; Zhou, X J; Erickson, R; Liao, S Y; Oveisi, F; Bemanian, S; Hollander, D

1996-05-01

2

Elemental analysis of lung tissue particles and intracellular iron content of alveolar macrophages in pulmonary alveolar proteinosis  

PubMed Central

Background Pulmonary alveolar proteinosis (PAP) is a rare disease occurred by idiopathic (autoimmune) or secondary to particle inhalation. The in-air microparticle induced X-ray emission (in-air micro-PIXE) system performs elemental analysis of materials by irradiation with a proton microbeam, and allows visualization of the spatial distribution and quantitation of various elements with very low background noise. The aim of this study was to assess the secondary PAP due to inhalation of harmful particles by employing in-air micro-PIXE analysis for particles and intracellular iron in parafin-embedded lung tissue specimens obtained from a PAP patient comparing with normal lung tissue from a non-PAP patient. The iron inside alveolar macrophages was stained with Berlin blue, and its distribution was compared with that on micro-PIXE images. Results The elements composing particles and their locations in the PAP specimens could be identified by in-air micro-PIXE analysis, with magnesium (Mg), aluminum (Al), silicon (Si), phosphorus (P), sulfur (S), scandium (Sc), potassium (K), calcium (Ca), titanium (Ti), chromium (Cr), copper (Cu), manganase (Mn), iron (Fe), and zinc (Zn) being detected. Si was the major component of the particles. Serial sections stained by Berlin blue revealed accumulation of sideromacrophages that had phagocytosed the particles. The intracellular iron content of alveolar macrophage from the surfactant-rich area in PAP was higher than normal lung tissue in control lung by both in-air micro-PIXE analysis and Berlin blue staining. Conclusion The present study demonstrated the efficacy of in-air micro-PIXE for analyzing the distribution and composition of lung particles. The intracellular iron content of single cells was determined by simultaneous two-dimensional and elemental analysis of paraffin-embedded lung tissue sections. The results suggest that secondary PAP is associated with exposure to inhaled particles and accumulation of iron in alveolar macrophages.

2011-01-01

3

Iron exposure modifies acetylcholinesterase activity in zebrafish (Danio rerio) tissues: distinct susceptibility of tissues to iron overload.  

PubMed

Iron is one the most abundant metals on the earth being essential for living organisms even though its free form can be toxic. The overload of this metal may be related with some disorders, like Alzheimer and Parkinson diseases, and hemochromatosis in the liver. The aim of the present study was to evaluate the effects of iron on acetylcholinesterase (AChE) activity in brain and liver of zebrafish and to investigate the possible correlation with the iron content in these tissues. Different corresponding concentrations of iron were tested using in vitro (0.018, 0.268, and 2.6 mM) and in vivo (1, 15, and 150 mg/l) assays. The in vitro studies showed that iron promoted a significant increase in AChE activity in brain (52%) and liver (53%) at the higher concentration (2.6 mM). In the in vivo assays, a significant increase in this enzyme activity was observed in the presence of 15 mg/l in both, brain (62%) and liver tissue (70%). Semiquantitative RT-PCR did not reveal significant changes in acetylthiocholinesterase mRNA levels. Moreover, we observed that iron content was significantly increased in liver tissue when exposed to 15 (226%) and 150 mg/l (200%). These results indicate that iron can promote significant alterations in AChE activity which probably is not directly related to the iron content in zebrafish tissues. PMID:21194010

Sant'Anna, M C B; Soares, Vanessa de Matas; Seibt, Kelly Juliana; Ghisleni, Gabriele; Rico, Eduardo Pacheco; Rosemberg, Denis Broock; de Oliveira, Jarbas Rodrigues; Schröder, Nadja; Bonan, Carla Denise; Bogo, Mauricio Reis

2011-09-01

4

[The content of iron, copper and zinc in 12 tissues of female swine in 11 age groups from birth to a body weight of 200 to 265 kg].  

PubMed

In female pigs in the age of one day (body mass: 1.89 +/- 0.20 kg) to that of on the average 1123 days (b. m: 200 to 265 kg) in 11 age-groups the weight of 12 different tissues as well as their content in Fe, Cu and Zn were analysed. The age dependent changes of the content are described and discussed. PMID:8223235

Bügelsack, G; Kolb, E; Salomon, F V; Nestler, K

1993-09-01

5

Impact of epidermal desquamation on tissue stores of iron  

PubMed Central

Background Although several billion corneocytes are shed from human skin daily, metabolic studies from 50 years ago led to the conclusion that corneocyte desquamation had no measurable impact on systemic protein or iron status in humans. Objective To measure iron content of internal organs after introducing local genetic changes in epidermis that alter iron metabolism in skin. Methods Iron was measured in tissues and blood from groups of animals 7 weeks after weaning in three different mouse models expressing a transgene in epidermis: a hyperproliferation model in which the HPV16 E7 gene causes a 3-fold increase in epidermal turnover; an epidermal iron sink model in which overexpression of the transferrin receptor causes a 3–4 fold increase of iron in epidermis; a systemic hemochromatosis knockout model that has been crossed with the epidermal iron sink model. Results In the hemochromatosis model with the iron sink transgene in epidermis, there was a statistically significant reduction in non-heme iron in serum and in the liver and kidney. In all models there was a statistically significant reduction in non-heme iron in the kidney. Conclusion Local changes in iron metabolism in epidermis can have a measurable impact on systemic iron metabolism. By implication, disruptions in epidermal homeostasis might affect systemic levels of trace nutrients, and circulating toxins might be remediated by sequestering them in epidermis.

Milstone, Leonard M.; Hu, Rong-Hua; Dziura, James D.; Zhou, Jing

2012-01-01

6

Folic acid and protein content in maternal diet and postnatal high-fat feeding affect the tissue levels of iron, zinc, and copper in the rat.  

PubMed

Although maternal, fetal, and placental mechanisms compensate for disturbances in the fetal environment, any nutritional inadequacies present during pregnancy may affect fetal metabolism, and their consequences may appear in later life. The aim of the present study is to investigate the influence of maternal diet during gestation on Fe, Zn, and Cu levels in the livers and kidneys of adult rats. The study was carried out on the offspring (n?=?48) of mothers fed either a protein-balanced or a protein-restricted diet (18% vs. 9% casein) during pregnancy, with or without folic acid supplementation (0.005- vs. 0.002-g folic acid/kg diet). At 10 weeks of age, the offspring of each maternal group were randomly assigned to groups fed either the AIN-93G diet or a high-fat diet for 6 weeks, until the end of the experiment. The levels of Fe, Zn, and Cu in the livers and kidneys were determined by the F-AAS method. It was found that postnatal exposure to the high-fat diet was associated with increased hepatic Fe levels (p?contents (p?contents (p?tissue mineral levels were also affected by protein and folic acid content in the maternal diet. Both prenatal protein restriction and folic acid supplementation increased the liver Zn content (p?content (p?

Król, Ewelina; Krejpcio, Zbigniew; Chmurzynska, Agata

2011-12-01

7

Tissue iron, copper and zinc levels in offspring of iron-sufficient and iron-deficient rats.  

PubMed

To study the effects of iron nutriture on tissue iron, copper and zinc contents, we fed iron-deficient or control diets to pregnant rats and their offspring. Pups were weaned to the same or opposite diet as that fed to their dams, yielding four groups: control-control (CC), control-deficient (CD), deficient-control (DC) and deficient-deficient (DD). Offspring were killed at 2, 21, 30, 60 and 90 days of age. Iron deficiency, induced by feeding a 5 ppm iron diet to the dam and/or to the weanlings, resulted in impaired body growth, lower hemoglobin and hematocrit levels and reduced iron levels in liver, spleen and kidney of the offspring. Two-day-old iron-deficient pups had hepatic copper levels 1.5- fold higher than control pups. By the end of the suckling period, hepatic copper levels in iron-deficient pups were 3-fold greater than those of control pups. Hepatic copper concentration in control-fed rats (CC and DC) declined with maturation. In deficient rats (CD and DD), this normal decrease in hepatic copper did not occur and in CD rats, there was a progressive accumulation of copper in the liver. Renal zinc concentrations were lower in CD and DD than in control-fed animals at 60 and 90 days of age. These interactions among iron, copper and zinc may assume clinical importance since iron deficiency is a common nutritional problem. PMID:7463170

Sherman, A R; Tissue, N T

1981-02-01

8

Magnetic resonance assessment of iron overload by separate measurement of tissue ferritin and hemosiderin iron  

PubMed Central

With transfusional iron overload, almost all the excess iron is sequestered intracellularly as rapidly mobilizable, dispersed, soluble, ferritin iron, and as aggregated, insoluble hemosiderin iron for long-term storage. Established magnetic resonance imaging (MRI) indicators of tissue iron (R2, R2*) are principally influenced by hemosiderin iron and change slowly, even with intensive iron chelation. Intracellular ferritin iron is evidently in equilibrium with the low-molecular-weight cytosolic iron pool that can change rapidly with iron chelation. We have developed a new magnetic resonance imaging (MRI) method to separately measure ferritin and hemosiderin iron, based on the non-monoexponential signal decay induced by aggregated iron in multiple-spin-echo sequences. We have initially validated the method in agarose phantoms and in human liver explants and shown the feasibility of its application in patients with thalassemia major. Measurement of tissue ferritin iron is a promising new means to rapidly evaluate the effectiveness of iron-chelating regimens.

Wu, Ed X.; Kim, Daniel; Tosti, Christina L.; Tang, Haiying; Jensen, Jens H.; Cheung, Jerry S.; Feng, Li; Au, Wing-Yan; Ha, Shau-Yin; Sheth, Sujit S.; Brown, Truman R.; Brittenham, Gary M.

2010-01-01

9

Reductive changes to polynuclear iron(III) clusters in iron-loaded human spleen tissue  

Microsoft Academic Search

Mössbauer spectroscopy was used to monitor, over a period of three days, the form of iron in iron-loaded spleen tissue following splenectomy from a patient with ?-thalassemia. The tissue was stored at room temperature for a three day period in order to allow degradation and autolytic processes to take place. The majority of the iron in the fresh spleen tissue

Wanida Chua-anusorn; Tim G. St. Pierre; David J. Macey; John Webb

1998-01-01

10

Increased iron (III) and total iron content in post mortem substantia nigra of parkinsonian brain  

Microsoft Academic Search

Summary Significant differences in the content of iron (III) and total iron were found in post mortem substantia nigra of Parkinson's disease. There was an increase of 176% in the levels of total iron and 255% of iron (III) in the substantia nigra of the parkinsonian patients compared to age matched controls. In the cortex (Brodmann area 21), hippocampus, putamen,

E. Sofic; P. Riederer; H. Heinsen; H. Beckmann; G. P. Reynolds; G. Hebenstreit; M. B. H. Youdim

1988-01-01

11

Melanin content of hamster tissues, human tissues, and various melanomas  

SciTech Connect

Melanin content (percentage by weight) was determined in both pigmented and nonpigmented tissues of Syrian golden hamsters bearing Greene melanoma. Melanin content was also measured in various other melanoma models (B-16 in C57 mice, Harding-Passey in BALB/c mice, and KHDD in C3H mice) and in nine human melanomas, as well as in selected normal tissues. The purpose was to evaluate the possible efficacy of chlorpromazine, which is known to bind to melanin, as a vehicle for boron transport in neutron capture therapy. Successful therapy would depend upon selective uptake and absolute concentration of borated compounds in tumors; these parameters will in turn depend upon melanin concentration in melanomas and nonpigmented ''background'' tissues. Hamster whole eyes, hamster melanomas, and other well-pigmented animal melanomas were found to contain 0.3 to 0.8% melanin by weight, whereas human melanomas varied from 0.1 to 0.9% (average, 0.35%). Other tissues, with the exception of skin, were lower in content by a factor of greater than or equal to30. Melanin pigment was extracted from tissues, and the melanin content was determined spectrophotometrically. Measurements were found to be sensitive to the presence of other proteins. Previous procedures for isolating and quantifying melanin often neglected the importance of removing proteins and other interfering nonmelanic substances.

Watts, K.P.; Fairchild, R.G.; Slatkin, D.N.; Greenberg, D.; Packer, S.; Atkins, H.L.; Hannon, S.J.

1981-02-01

12

Pattern of iron distribution in maternal and filial tissues in wheat grains with contrasting levels of iron  

PubMed Central

Iron insufficiency is a worldwide problem in human diets. In cereals like wheat, the bran layer of the grains is an important source of iron. However, the dietary availability of iron in wheat flour is limited due to the loss of the iron-rich bran during milling and processing and the presence of anti-nutrients like phytic acid that keep iron strongly chelated in the grain. The present study investigated the localization of iron and phosphorus in grain tissues of wheat genotypes with contrasting grain iron content using synchrotron-based micro-X-ray fluorescence (micro-XRF) and micro-proton-induced X-ray emission (micro-PIXE). X-ray absorption near-edge spectroscopy (XANES) was employed to determine the proportion of divalent and trivalent forms of Fe in the grains. It revealed the abundance of oxygen, phosphorus, and sulphur in the local chemical environment of Fe in grains, as Fe-O-P-R and Fe-O-S-R coordination. Contrasting differences were noticed in tissue-specific relative localization of Fe, P, and S among the different genotypes, suggesting a possible effect of localization pattern on iron bioavailability. The current study reports the shift in iron distribution from maternal to filial tissues of grains during the evolution of wheat from its wild relatives to the present-day cultivated varieties, and thus suggests the value of detailed physical localization studies in varietal improvement programmes for food crops.

Tuli, Rakesh

2013-01-01

13

Intestinal HIF2? promotes tissue-iron accumulation in disorders of iron overload with anemia.  

PubMed

Several distinct congenital disorders can lead to tissue-iron overload with anemia. Repeated blood transfusions are one of the major causes of iron overload in several of these disorders, including ?-thalassemia major, which is characterized by a defective ?-globin gene. In this state, hyperabsorption of iron is also observed and can significantly contribute to iron overload. In ?-thalassemia intermedia, which does not require blood transfusion for survival, hyperabsorption of iron is the leading cause of iron overload. The mechanism of increased iron absorption in ?-thalassemia is unclear. We definitively demonstrate, using genetic mouse models, that intestinal hypoxia-inducible factor-2? (HIF2?) and divalent metal transporter-1 (DMT1) are activated early in the pathogenesis of ?-thalassemia and are essential for excess iron accumulation in mouse models of ?-thalassemia. Moreover, thalassemic mice with established iron overload had significant improvement in tissue-iron levels and anemia following disruption of intestinal HIF2?. In addition to repeated blood transfusions and increased iron absorption, chronic hemolysis is the major cause of tissue-iron accumulation in anemic iron-overload disorders caused by hemolytic anemia. Mechanistic studies in a hemolytic anemia mouse model demonstrated that loss of intestinal HIF2?/DMT1 signaling led to decreased tissue-iron accumulation in the liver without worsening the anemia. These data demonstrate that dysregulation of intestinal hypoxia and HIF2? signaling is critical for progressive iron overload in ?-thalassemia and may be a novel therapeutic target in several anemic iron-overload disorders. PMID:24282296

Anderson, Erik R; Taylor, Matthew; Xue, Xiang; Ramakrishnan, Sadeesh K; Martin, Angelical; Xie, Liwei; Bredell, Bryce X; Gardenghi, Sara; Rivella, Stefano; Shah, Yatrik M

2013-12-10

14

The ubiquinone content of animal tissues  

PubMed Central

1. A method was developed for the analysis of ubiquinone in animal tissues and the recovery of added ubiquinone tested in liver of the rat, Crocodylus porosus and Squalus acanthias. 2. The ubiquinone content of heart, liver and gut (or breast muscle in birds) was measured in 67 different animal species, selected to be representative of all the vertebrate classes. 3. The suggestion is advanced that the possession of appreciable amounts of endogenous tissue ubiquinone is usually characteristic of evolutionarily advanced vertebrates, and the biological and biochemical significance of the results is discussed.

Diplock, A. T.; Haslewood, G. A. D.

1967-01-01

15

[Method of quantitative iron determination in the serum, urine and tissue].  

PubMed

In this paper the methodology of the quantitative determination of the iron in serum, urine and tissue is described. For the quantitative recognition of the iron in the serum the photometric determination with bathophenanthroline as well as the atomic absorption spectrophotometry may be used. The atomic absorption spectrophotometry may be used. The atomic absorption spectrophotometry is particularly suited for the measurement of the iron content in the urine. Tissue is disintegrated by wet ash formation and also determined by atomic absorption spectrophotometry. PMID:6730592

Preu, E; Schmidt, U; Lüftner, J; Anschütz, U

1984-04-15

16

Determining Iron Content in Foods by Spectrophotometry.  

ERIC Educational Resources Information Center

Describes a laboratory experiment for secondary school chemistry students utilizing the classic reaction between the iron(III) ion and the thiocyanate ion. The experiment also works very well in other chemistry courses as an experience in spectrophotometric analysis. (PVD)

Adams, Paul E.

1995-01-01

17

Bioinorganic transformations of liver iron deposits observed by tissue magnetic characterisation in a rat model.  

PubMed

The magnetic properties and the ultrastructure, with special emphasis on the nanometric range, of liver tissues in an iron overload rat model have been investigated. The tissues of the animals, sacrificed at different times after a single iron dextran injection, have been characterised by magnetic AC susceptibility measurements together with transmission electron microscopy (TEM) and selected area electron diffraction (SAED) as helping techniques. It has been observed that few days after the iron administration the liver contains at least two iron species: (i) akaganéite nanoparticles, coming from iron dextran and (ii) ferrihydrite nanoparticles corresponding to ferritin. The magnetic susceptibility of the tissues depends not only on the elemental iron content but also on its distribution among chemical species, and varies in a remarkable regular manner as a function of the elapsed time since the iron administration. The results are of relevance with respect to non-invasive techniques for liver iron determination, directly or indirectly based on the magnetic susceptibility of the tissues, as biomagnetic liver susceptometry (BLS) and magnetic resonance (MRI) image treatment. PMID:16899298

Gutiérrez, Lucía; Lázaro, Francisco J; Abadía, Ana R; Romero, María S; Quintana, Carmen; Puerto Morales, M; Patiño, Cristina; Arranz, Rocío

2006-11-01

18

Dietary Iron Concentration May Influence Aging Process by Altering Oxidative Stress in Tissues of Adult Rats  

PubMed Central

Iron is an essential element. However, in its free form, iron participates in redox-reactions, leading to the production of free radicals that increase oxidative stress and the risk of damaging processes. Living organisms have an efficient mechanism that regulates iron absorption according to their iron content to protect against oxidative damage. The effects of restricted and enriched-iron diets on oxidative stress and aging biomarkers were investigated. Adult Wistar rats were fed diets containing 10, 35 or 350 mg/kg iron (adult restricted-iron, adult control-iron and adult enriched-iron groups, respectively) for 78 days. Rats aged two months were included as a young control group. Young control group showed higher hemoglobin and hematocrit values, lower levels of iron and lower levels of MDA or carbonyl in the major studied tissues than the adult control group. Restricted-iron diet reduced iron concentrations in skeletal muscle and oxidative damage in the majority of tissues and also increased weight loss. Enriched-iron diet increased hematocrit values, serum iron, gamma-glutamyl transferase, iron concentrations and oxidative stress in the majority of tissues. As expected, young rats showed higher mRNA levels of heart and hepatic L-Ferritin (Ftl) and kidneys SMP30 as well as lower mRNA levels of hepatic Hamp and interleukin-1 beta (Il1b) and also lower levels of liver protein ferritin. Restricted-iron adult rats showed an increase in heart Ftl mRNA and the enriched-iron adult rats showed an increase in liver nuclear factor erythroid derived 2 like 2 (Nfe2l2) and Il1b mRNAs and in gut divalent metal transporter-1 mRNA (Slc11a2) relative to the control adult group. These results suggest that iron supplementation in adult rats may accelerate aging process by increasing oxidative stress while iron restriction may retards it. However, iron restriction may also impair other physiological processes that are not associated with aging.

Arruda, Lorena Fernandes; Arruda, Sandra Fernandes; Campos, Natalia Aboudib; de Valencia, Fernando Fortes; Siqueira, Egle Machado de Almeida

2013-01-01

19

Macrophage Content in Subcutaneous Adipose Tissue  

PubMed Central

OBJECTIVE— In severely obese individuals and patients with diabetes, accumulation and activation of macrophages in adipose tissue has been implicated in the development of obesity-associated complications, including insulin resistance. We sought to determine whether in a healthy population, adiposity, sex, age, or insulin action is associated with adipose tissue macrophage content (ATMc) and/or markers of macrophage activation. RESEARCH DESIGN AND METHODS— Subcutaneous ATMc from young adult Pima Indians with a wide range of adiposity (13–46% body fat, by whole-body dual-energy X-ray absorptiometry) and insulin action (glucose disposal rate 1.6–9 mg/kg estimated metabolic body size/min, by glucose clamp) were measured. We also measured expression in adipose tissue of factors implicated in macrophage recruitment and activation to determine any association with ATMc and insulin action. RESULTS— ATMc, as assessed by immunohistochemistry (Mphi) and by macrophage-specific gene expression (CD68, CD11b, and CSF1R), were correlated with percent body fat, age, and female sex. Gene expression of CD68, CD11b, and CSF1R but not Mphi was correlated negatively with glucose disposal rate but not after adjustment for percent body fat, age, and sex. However, adipose tissue expression of plasminogen activator inhibitor type-1 (PAI-1) and CD11 antigen-like family member C (CD11c), markers produced by macrophages, were negatively correlated with adjusted glucose disposal rate (r = ?0.28, P = 0.05 and r = ?0.31, P = 0.03). CONCLUSIONS— ATMc is correlated with age and adiposity but not with insulin action independent of adiposity in healthy human subjects. However, PAI-1 and CD11c expression are independent predictors of insulin action, indicating a possible role for adipose tissue macrophage activation.

Ortega Martinez de Victoria, Emilio; Xu, Xiaoyuan; Koska, Juraj; Francisco, Ann Marie; Scalise, Michael; Ferrante, Anthony W.; Krakoff, Jonathan

2009-01-01

20

Cast Iron With High Carbon Content  

NASA Technical Reports Server (NTRS)

Method proposed for solidifying high-carbon cast iron without carbon particles segregating at upper surface. Solidification carried out in low gravity, for example on airplane flying free-fall parabolic trajectory. Many different microstructures obtained by proposed technique, and percentage by weight of carbon retained in melt much higher than at present.

Curreri, P. A.; Hendrix, J. C.; Stefanescu, D. M.

1986-01-01

21

Mechanisms of Tissue-Iron Relaxivity: Nuclear Magnetic Resonance Studies of Human Liver Biopsy Specimens  

PubMed Central

MRI is becoming an increasingly important tool to assess iron overload disorders, but the complex nature of proton–iron interactions has troubled noninvasive iron quantification. Intersite and intersequence variability as well as methodological inaccuracies have been limiting factors to its widespread clinical use. It is important to understand the underlying proton relaxation mechanisms within the (human) tissue environment to address these differences. In this respect, NMR relaxometry was performed on 10 fresh human liver biopsy specimens taken from patients with transfusion-dependent anemia. T1 (1/R1) inversion recovery, T2 (1/R2) single echo, and multiecho T2 CPMG measurements were performed on a 60-MHz Bruker Minispectrometer. NMR parameters were compared to quantitative iron levels and tissue histology. Relaxivities R1 and R2 both increased linearly with hepatic iron content, with R2 being more sensitive to iron. CPMG data were well described by a chemical-exchange model and predicted effective iron center dimensions consistent with hemosiderin-filled lysosomes. Nonexponential relaxation was evident at short refocusing intervals with R2 and amplitude behavior suggestive of magnetic susceptibility-based compartmentalization rather than anatomic subdivisions. NMR relaxometry of human liver biopsy specimens yields unique insights into the mechanisms of tissue–iron relaxivity.

Ghugre, Nilesh R.; Coates, Thomas D.; Nelson, Marvin D.; Wood, John C.

2010-01-01

22

High Thoughput, High Content Tissue Cyotometry  

Microsoft Academic Search

The study of pathogenesis of many diseases requires quantification of cell-cell and cell-extracellular matrix interactions\\u000a on the tissue level. A particularly promising assay technology is high throughput multiphoton tissue cytometry. This technique\\u000a is based on mulitphoton microscopy (MPM) allowing minimally invasive 3D resolved imaging deep inside tissues. MPM not only\\u000a can provide tissue and cellular morphological information but can also

Peter T. C. So

23

Mesothelioma and analysis of tissue fiber content.  

PubMed

The strong relationship between mesothelioma and asbestos exposure is well established. The analysis of lung asbestos burden by light and electron microscopy assisted to understand the increased incidence of mesothelioma in asbestos mining and consuming nations.The data on the occupational exposure to asbestos are important information for the purpose of compensation of occupational disease No. 4105 (asbestos-associated mesothelioma) in Germany.However, in many cases the patients have forgotten conditions of asbestos exposure or had no knowledge about the used materials with components of asbestos. Mineral fiber analysis can provide valuable information for the research of asbestos-associated diseases and for the assessment of exposure. Because of the variability of asbestos exposure and long latency periods, the analysis of asbestos lung content is a relevant method for identification of asbestos-associated diseases. Also, sources of secondary exposure, so called "bystander exposition" or environmental exposure can be examined by mineral fiber analysis.Household contacts to asbestos are known for ten patients (1987-2009) in the German mesothelioma register; these patients lived together with family members working in the asbestos manufacturing industry.Analysis of lung tissue for asbestos burden offers information on the past exposure. The predominant fiber-type identified by electron microscopy in patients with mesothelioma is amphibole asbestos (crocidolite or amosite). Latency times (mean 42.5 years) and mean age at the time of diagnose in patients with mesothelioma are increasing (65.5 years). The decrease of median asbestos burden of the lung in mesothelioma patients results in disease manifestation at a higher age.Lung dust analyses are a relevant method for the determination of causation in mesothelioma. Analysis of asbestos burden of the lung and of fiber type provides insights into the pathogenesis of malignant mesothelioma. The most important causal factor for the development of mesothelioma is still asbestos exposure. PMID:21479897

Neumann, Volker; Löseke, Stefan; Tannapfel, Andrea

2011-01-01

24

Magnetic resonance imaging contrast of iron oxide nanoparticles developed for hyperthermia is dominated by iron content.  

PubMed

Abstract Purpose: Magnetic iron oxide nanoparticles (MNPs) are used as contrast agents for magnetic resonance imaging (MRI) and hyperthermia for cancer treatment. The relationship between MRI signal intensity and cellular iron concentration for many new formulations, particularly MNPs having magnetic properties designed for heating in hyperthermia, is lacking. In this study, we examine the correlation between MRI T2 relaxation time and iron content in cancer cells loaded with various MNP formulations. Materials and methods: Human prostate carcinoma DU-145 cells were loaded with starch-coated bionised nanoferrite (BNF), iron oxide (Nanomag® D-SPIO), Feridex™, and dextran-coated Johns Hopkins University (JHU) particles at a target concentration of 50?pg Fe/cell using poly-D-lysine transfection reagent. T2-weighted MRI of serial dilutions of these labelled cells was performed at 9.4?T and iron content quantification was performed using inductively coupled plasma mass spectrometry (ICP-MS). Clonogenic assay was used to characterise cytotoxicity. Results: No cytotoxicity was observed at twice the target intracellular iron concentration (?100?pg Fe/cell). ICP-MS revealed highest iron uptake efficiency with BNF and JHU particles, followed by Feridex and Nanomag-D-SPIO, respectively. Imaging data showed a linear correlation between increased intracellular iron concentration and decreased T2 times, with no apparent correlation among MNP magnetic properties. Conclusions: This study demonstrates that for the range of nanoparticle concentrations internalised by cancer cells the signal intensity of T2-weighted MRI correlates closely with absolute iron concentration associated with the cells. This correlation may benefit applications for cell-based cancer imaging and therapy including nanoparticle-mediated drug delivery and hyperthermia. PMID:24773041

Wabler, Michele; Zhu, Wenlian; Hedayati, Mohammad; Attaluri, Anilchandra; Zhou, Haoming; Mihalic, Jana; Geyh, Alison; Deweese, Theodore L; Ivkov, Robert; Artemov, Dmitri

2014-05-01

25

Arsenic Content in Tissues of Fish from the River Elbe  

Microsoft Academic Search

âelechovská O., Z. Svobodová, T. Randák: Arsenic Content in Tissues of Fish from the River Elbe. Acta Vet. Brno 2005, 74: 419-425. The aim of the study was to evaluate arsenic content in tissues (muscle, liver, kidneys, gonads) of fish caught in selected localities along the River Elbe and its tributary the Vltava in 1999, 2002 and 2003, and in

Z. SVOBODOVÁ; T. RANDÁK

2005-01-01

26

Method and apparatus for determining fat content of tissue  

DOEpatents

A method and apparatus for determining characteristics of tissue is disclosed. The method comprises supplying optical energy to a tissue and detecting at a plurality of locations consequent energy scattered by the tissue. Analysis of the scattered energy as taught herein provides information concerning the properties of the tissue, specifically information related to the fat and lean content and thickness of the tissue. The apparatus comprises a light source adapted to deliver optical energy to a tissue. A plurality of detectors can be mounted at different positions relative to the source to detect energy scattered by the tissue. A signal processor as taught herein can determine characteristics of the tissue from the signals from the detectors and locations of the detectors, specifically information related to the fat and lean content and thickness of the tissue.

Weber, Thomas M. (Albuquerque, NM) [Albuquerque, NM; Spletzer, Barry L. (Albuquerque, NM) [Albuquerque, NM; Bryan, Jon R. (Edgewood, NM) [Edgewood, NM; Dickey, Fred M. (Albuquerque, NM) [Albuquerque, NM; Shagam, Richard N. (Albuquerque, NM) [Albuquerque, NM; Gooris, Luc (Rancho Santa Margarita, CA) [Rancho Santa Margarita, CA

2001-01-01

27

Organ and Tissue Transplants: Table of Contents.  

National Technical Information Service (NTIS)

The table of contents lists papers under the following categories: Kidney transplants; Lung transplants; Transplants of endocrine glands; Transplants of extremities; Transplants of liver, spleen, heart and other organs; Transplantation of bone marrow; Ker...

B. V. Petrovskii

1967-01-01

28

Effects of mineral content of bovine drinking water: does iron content affect milk quality?  

PubMed

The composition of water given to dairy cattle is often ignored, yet water is a very important nutrient and plays a major role in milk synthesis. The objective of this study was to study effects of elevated levels of iron in bovine drinking water on milk quality. Ferrous lactate treatments corresponding to 0, 2, 5, and 12.5mg/kg drinking water concentrations were delivered through the abomasum at 10 L/d to 4 lactating dairy cows over 4 periods (1 wk infusion/period) in a Latin square design. On d 6 of infusion, milk was collected, processed (homogenized, pasteurized), and analyzed. Mineral content (Fe, Cu, P, Ca) was measured by inductively coupled plasma mass spectrometry. Oxidative stability of whole processed milk was measured by the thiobarbituric acid reactive substances (TBARS) assay for malondialdehyde (MDA) and sensory analysis (triangle test) within 72 h of processing and after 7d of storage (4°C). Significant sensory differences between processed milks from cows receiving iron and the control infusion were observed. No differences in TBARS (1.46±0.04 mg of MDA/kg) or mineral content (0.22±0.01 mg/kg Fe) were observed. A 2-way interaction (iron treatment by cow) for Ca, Cu, and Fe concentrations was seen. While iron added directly to milk causes changes in oxidation of milk, high levels of iron given to cattle have subtle effects that initially may not be obvious. PMID:24140329

Mann, G R; Duncan, S E; Knowlton, K F; Dietrich, A D; O'Keefe, S F

2013-12-01

29

Iron solubility related to particle sulfur content in source emission and ambient fine particles.  

PubMed

The chemical factors influencing iron solubility (soluble iron/total iron) were investigated in source emission (e.g., biomass burning, coal fly ash, mineral dust, and mobile exhaust) and ambient (Atlanta, GA) fine particles (PM2.5). Chemical properties (speciation and mixing state) of iron-containing particles were characterized using X-ray absorption near edge structure (XANES) spectroscopy and micro-X-ray fluorescence measurements. Bulk iron solubility (soluble iron/total iron) of the samples was quantified by leaching experiments. Major differences were observed in iron solubility in source emission samples, ranging from low solubility (<1%, mineral dust and coal fly ash) up to 75% (mobile exhaust and biomass burning emissions). Differences in iron solubility did not correspond to silicon content or Fe(II) content. However, source emission and ambient samples with high iron solubility corresponded to the sulfur content observed in single particles. A similar correspondence between bulk iron solubility and bulk sulfate content in a series of Atlanta PM2.5 fine particle samples (N = 358) further supported this trend. In addition, results of linear combination fitting experiments show the presence of iron sulfates in several high iron solubility source emission and ambient PM2.5 samples. These results suggest that the sulfate content (related to the presence of iron sulfates and/or acid-processing mechanisms by H(2)SO(4)) of iron-containing particles is an important proxy for iron solubility. PMID:22621615

Oakes, M; Ingall, E D; Lai, B; Shafer, M M; Hays, M D; Liu, Z G; Russell, A G; Weber, R J

2012-06-19

30

Threshold effect of liver iron content on hepatic inflammation and fibrosis in hepatitis B and C  

Microsoft Academic Search

Background\\/Aims: In hepatitis C, iron depletion may improve serum aminotransferases and the response to interferon, but it is not known whether inflammation and fibrosis correlate with hepatic iron content. Our aim was to establish whether hepatic from content correlates with histological and serum indices of hepatic inflammation and fibrosis in hepatitis B and C.Methods: Total hepatic iron was measured using

Nele K. Beinker; Michael D Voigt; Michael Arendse; Julian Smit; Ilse A. Stander; Ralph E. Kirsch

1996-01-01

31

Reticulocyte hemoglobin content in the evaluation of iron status of hemodialysis patients  

Microsoft Academic Search

Reticulocyte hemoglobin content in the evaluation of iron status in hemodialysis patients. The assessment of iron status for hemodialysis patients has been hindered by the inaccuracy of commonly used diagnostic tests. A novel assay, the reticulocyte hemoglobin content (CHr), has recently been found to sensitively detect functional iron deficiency among nonuremic patients treated with recombinant erythropoietin (rHuEPO). The purpose of

Steven Fishbane; Cynthia Galgano; Robert C Langley; William Canfield; John K Maesaka

1997-01-01

32

Desferrithiocin Analogue Iron Chelators: Iron Clearing Efficiency, Tissue Distribution, and Renal Toxicity  

PubMed Central

The current solution to iron-mediated damage in transfusional iron overload disorders is decorporation of excess unmanaged metal, chelation therapy. The clinical development of the tridentate chelator deferitrin (1, Table 1) was halted due to nephrotoxicity. It was then shown by replacing the 4?-(HO) of 1 with a 3,6,9-trioxadecyloxy group, the nephrotoxicity could be ameliorated. Further structure-activity relationship studies have established that the length and the position of the polyether backbone controlled: (1) the ligand’s iron clearing efficiency (ICE), (2) chelator tissue distribution, (3) biliary ferrokinetics, and (4) tissue iron reduction. The current investigation compares the ICE and tissue distribution of a series of (S)-4,5-dihydro-2-[2-hydroxy-4-(polyether)phenyl]-4-methyl-4-thiazole-carboxylic acids (Table 1, 3–5) and the (S)-4,5-dihydro-2-[2-hydroxy-3-(polyether)phenyl]-4-methyl-4-thiazolecarboxylic acids (Table 1, 8–10). The three most effective polyether analogues, in terms of performance ratio (PR), defined as mean ICEprimate/ICErodent, are 3 (PR 1.1), 8, (PR 1.5), and 9, now in human trials, (PR 2.2). At the onset of the clinical trial on 9, no data were available for ligand 3 or 8. This is unfortunate, as 3 has many advantages over 9, e.g., the ICE of 3 in rats is 2.5-fold greater than that of 9 and analogue 3 achieves very high levels in the liver, pancreas, and heart, the organs most affected by iron overload. Finally, the impact of 3 on the urinary excretion of kidney injury molecule-1 (Kim-1), an early diagnostic biomarker for monitoring acute kidney toxicity, has been carried out in rats; no evidence of nephrotoxicity was found. Overall, the results suggest that 3 would be a far superior clinical candidate to 9.

Bergeron, Raymond J.; Wiegand, Jan; Bharti, Neelam; McManis, James S.; Singh, Shailendra

2012-01-01

33

Iron from nanocompounds containing iron and zinc is highly bioavailable in rats without tissue accumulation  

NASA Astrophysics Data System (ADS)

Effective iron fortification of foods is difficult, because water-soluble compounds that are well absorbed, such as ferrous sulphate (FeSO4), often cause unacceptable changes in the colour or taste of foods. Poorly water-soluble compounds, on the other hand, cause fewer sensory changes, but are not well absorbed. Here, we show that poorly water-soluble nanosized Fe and Fe/Zn compounds (specific surface area ~190 m2 g-1) made by scalable flame aerosol technology have in vivo iron bioavailability in rats comparable to FeSO4 and cause less colour change in reactive food matrices than conventional iron fortificants. The addition of Zn to FePO4 and Mg to Fe/Zn oxide increases Fe absorption from the compounds, and doping with Mg also improves their colour. After feeding rats with nanostructured iron-containing compounds, no stainable Fe was detected in their gut wall, gut-associated lymphatics or other tissues, suggesting no adverse effects. Nanosizing of poorly water-soluble Fe compounds sharply increases their absorption and nutritional value.

Hilty, Florentine M.; Arnold, Myrtha; Hilbe, Monika; Teleki, Alexandra; Knijnenburg, Jesper T. N.; Ehrensperger, Felix; Hurrell, Richard F.; Pratsinis, Sotiris E.; Langhans, Wolfgang; Zimmermann, Michael B.

2010-05-01

34

Iron from nanocompounds containing iron and zinc is highly bioavailable in rats without tissue accumulation.  

PubMed

Effective iron fortification of foods is difficult, because water-soluble compounds that are well absorbed, such as ferrous sulphate (FeSO(4)), often cause unacceptable changes in the colour or taste of foods. Poorly water-soluble compounds, on the other hand, cause fewer sensory changes, but are not well absorbed. Here, we show that poorly water-soluble nanosized Fe and Fe/Zn compounds (specific surface area approximately 190 m(2) g(-1)) made by scalable flame aerosol technology have in vivo iron bioavailability in rats comparable to FeSO(4) and cause less colour change in reactive food matrices than conventional iron fortificants. The addition of Zn to FePO(4) and Mg to Fe/Zn oxide increases Fe absorption from the compounds, and doping with Mg also improves their colour. After feeding rats with nanostructured iron-containing compounds, no stainable Fe was detected in their gut wall, gut-associated lymphatics or other tissues, suggesting no adverse effects. Nanosizing of poorly water-soluble Fe compounds sharply increases their absorption and nutritional value. PMID:20418865

Hilty, Florentine M; Arnold, Myrtha; Hilbe, Monika; Teleki, Alexandra; Knijnenburg, Jesper T N; Ehrensperger, Felix; Hurrell, Richard F; Pratsinis, Sotiris E; Langhans, Wolfgang; Zimmermann, Michael B

2010-05-01

35

Both immanently high active iron contents and increased root ferrous uptake in response to low iron stress contribute to the iron deficiency tolerance in Malus xiaojinensis.  

PubMed

To better understand the mechanism of low-iron stress tolerance in Malus xiaojinensis, the differences in physiological parameters and gene expression between an iron deficiency-sensitive species, Malus baccata, and an iron deficiency-tolerant species, M. xiaojinensis were investigated under low-iron (4 ?M Fe) conditions. Under iron sufficient conditions, the expressions of iron uptake- and transport-related genes, i.e. FIT1, IRT1, CS1, FRD3 and NRMAP1, and the immanent leaf and root active iron contents were higher in M. xiaojinensis than those in M. baccata. However, on the first three days of low iron stress, the rhizospheric pH decreased and the root ferric chelate reductase (FCR) activity and the expression of ferrous uptake- and iron transport-related genes in the roots increased significantly only in M. xiaojinensis. Leaf chlorosis occurred on the 3rd and the 9th day after low-iron treatment in M. baccata and M. xiaojinensis, respectively. The expression of iron relocalization-related genes, such as NAS1, FRD3 and NRMAP3, increased after the 5th or 6th day of low iron stress in leaves of M. xiaojinensis, whereas the expression of NAS1, FRD3 and NRMAP3 in the leaves of M. baccata increased immediately after the onset of low iron treatment. Conclusively, the relative high active iron contents caused by the immanently active root ferrous uptake and the increased root ferrous uptake in response to low iron stress were the dominant mechanisms for the tolerance to iron deficiency in M. xiaojinensis. PMID:24268163

Zha, Qian; Wang, Yi; Zhang, Xin-Zhong; Han, Zhen-Hai

2014-01-01

36

Stoichiometry of iron binding by uteroferrin and its relationship to phosphate content.  

PubMed

The analysis of uteroferrin's iron content by an acid-release method used in previous studies shows a critical dependence on phosphate, i.e. the native phosphate-free enzyme yields two irons/molecule, while enzyme with one tightly bound phosphate gives closer to one iron. In contrast, two irons/molecule of protein are found in samples assayed by a wet ash method. When iron assays are carried out on samples of purple two-iron protein reductively stripped of their phosphate, both methods again yield two iron atoms/molecule. However, the discrepancy between the two methods recurs when phosphate is added to samples of pink protein which were formerly free of phosphate. These results suggest that phosphate bound to native uteroferrin may have interfered with iron determinations in some earlier studies. Furthermore, enzyme samples with one tightly bound phosphate have the optical purity index (i.e.A280/A545 approximately less than 14.0) and extinction coefficient at 280 nm, characteristic of putative one-iron preparations. There is little doubt, therefore, that previous EPR, magnetic susceptibility, and iron titration experiments thought to have been carried out on genuine one-iron preparations were in fact done on samples of two-iron protein bearing a single tightly bound phosphate. Reassessment of earlier studies indicates that the properties of putative one-iron preparations may be reconciled with those of the two-iron phosphate-laden protein studied here. PMID:6698956

Antanaitis, B C; Aisen, P

1984-02-25

37

[Cytophotometric determination of non-heme iron in hepatocytes. II. Effect of fixation on the cell iron content].  

PubMed

The study deals with the effect of different fixatives, such as absolute methanol, 96% ethanol, 10% buffered neutral formalin, as well as mixtures: methanol-formalin-acetic acid and ethanol-formalin-acetic acid (Tellesnitsky's solution) on preservation of iron in isolated hepatocytes of rats on a diet with addition of 2% carbonyl iron. The iron preservation in cells, on application of different fixatives and performance of Perls' reaction, was evaluated by the intensity of cell staining that was measured using cytospectrophotometer. The best preservation of iron in cells has been achieved when using alcohol fixatives only. Fixation of preparations with the methanol-formalin-aceticacid mixture also produced no decrease in the iron content in hepatocytes, however, morphology of the stained cells was much worse than after methanol and ethanol fixation. Fixation with Tellesnitsky's solution resulted in a 36% reduction of the cellular iron content, whereas fixation with 10% neutral formalin reduced iron content by 58%, as compared with methanol fixation. A prolongation formalin fixation from 10 min to 24 hr had no effect on the intensity of Perls' reaction. PMID:9778734

Okon, E E

1998-01-01

38

The effect of copper on iron reduction and its application to the determination of total iron content in iron and copper ores by potassium dichromate titration.  

PubMed

The International Standard Organization (ISO) specifies two titrimetric methods for the determination of total iron content in iron ores using potassium dichromate as titrant after reduction of the iron(III) by tin(II) chloride and/or titanium(III) chloride. These two ISO methods (ISO2597-1 and ISO2597-2) require nearly boiling-point temperature for iron(III) reduction and suffer from copper interference and/or mercury pollution. In this study, potassium borohydride was used for reduction of iron(III) catalyzed by copper ions at ambient temperatures. In the absence of copper, iron(III) reduction by potassium borohydride was sluggish while a trace amount of copper significantly accelerated the reduction and reduced potassium borohydride consumption. The catalytic mechanism of iron(III) reduction in sulfuric acid and hydrochloric acid was investigated. Potassium borohydride in sodium hydroxide solution was stable without a significant degradation within 24h at ambient conditions and the use of potassium borohydride prepared in sodium hydroxide solution was safe and convenient in routine applications. The applicability of potassium borohydride reduction for the determination of total iron content by potassium dichromate titration was demonstrated by comparing with the ISO standard method using iron and copper ore reference materials and iron ore samples. PMID:24840467

Hu, Hanjun; Tang, Yang; Ying, Haisong; Wang, Minghai; Wan, Pingyu; Jin Yang, X

2014-07-01

39

MRI evaluation of tissue iron burden in patients with ?-thalassaemia major  

Microsoft Academic Search

?-Thalassaemia major is a hereditary haemolytic anaemia that is treated with multiple blood transfusions. A major complication\\u000a of this treatment is iron overload, which leads to cell death and organ dysfunction. Chelation therapy, used for iron elimination,\\u000a requires effective monitoring of the body burden of iron, for which serum ferritin levels and liver iron content measured\\u000a in liver biopsies are

Maria I. Argyropoulou; Loukas Astrakas

2007-01-01

40

Tissue fusion bursting pressure and the role of tissue water content  

NASA Astrophysics Data System (ADS)

Tissue fusion is a complex, poorly understood process which bonds collagenous tissues together using heat and pressure. The goal of this study is to elucidate the role of hydration in bond efficacy. Hydration of porcine splenic arteries (n=30) was varied by pre-fusion treatments: 24-48 hour immersion in isotonic, hypotonic, or hypertonic baths. Treated arteries were fused in several locations using Conmed's Altrus thermal fusion device and the bursting pressure was then measured for each fused segment. Artery sections were then weighed before and after lyophilization, to quantify water content. Histology (HE, EVG staining) enabled visualization of the bonding interface. Bursting pressure was significantly greater (p=4.17 E-ll) for the hypotonic group (607.6 +/- 83.2mmHg), while no significant difference existed between the isotonic (332.6 +/- 44.7mmHg) and hypertonic (348.7 +/- 44.0mmHg) treatment groups. Total water content varied (p=8.80 E-24) from low water content in the hypertonic samples (72.5% weight +/- 0.9), to high water content in the hypotonic samples (83.1% weight +/- 1.9), while the isotonic samples contained 78.8% weight +/- 1.1. Strength differences between the treated vessels imply that bound water driven from the tissue during fusion may reveal available collagen crosslinking sites to facilitate bond formation during the fusion process. Thus when the tissue contains greater bound water volumes, more crosslinking sites may become available during fusion, leading to a stronger bond. This study provides an important step towards understanding the chemistry underlying tissue fusion and the mechanics of tissue fusion as a function of bound water within the tissue.

Cezo, James; Kramer, Eric; Taylor, Kenneth; Ferguson, Virginia; Rentschler, Mark

2013-02-01

41

Verification of Steelmaking Slags Iron Content Final Technical Progress Report  

SciTech Connect

The steel industry in the United States generates about 30 million tons of by-products each year, including 6 million tons of desulfurization and BOF/BOP slag. The recycling of BF (blast furnace) slag has made significant progress in past years with much of the material being utilized as construction aggregate and in cementitious applications. However, the recycling of desulfurization and BOF/BOP slags still faces many technical, economic, and environmental challenges. Previous efforts have focused on in-plant recycling of the by-products, achieving only limited success. As a result, large amounts of by-products of various qualities have been stockpiled at steel mills or disposed into landfills. After more than 50 years of stockpiling and landfilling, available mill site space has diminished and environmental constraints have increased. The prospect of conventionally landfilling of the material is a high cost option, a waste of true national resources, and an eternal material liability issue. The research effort has demonstrated that major inroads have been made in establishing the viability of recycling and reuse of the steelmaking slags. The research identified key components in the slags, developed technologies to separate the iron units and produce marketable products from the separation processes. Three products are generated from the technology developed in this research, including a high grade iron product containing about 90%Fe, a medium grade iron product containing about 60% Fe, and a low grade iron product containing less than 10% Fe. The high grade iron product contains primarily metallic iron and can be marketed as a replacement of pig iron or DRI (Direct Reduced Iron) for steel mills. The medium grade iron product contains both iron oxide and metallic iron and can be utilized as a substitute for the iron ore in the blast furnace. The low grade iron product is rich in calcium, magnesium and iron oxides and silicates. It has a sufficient lime value and can be utilized for acid mine drainage treatment. Economic analysis from this research demonstrates that the results are favorable. The strong demand and the increase of price of the DRI and pig iron in recent years are particularly beneficial to the economics. The favorable economics has brought commercial interests. ICAN Global has obtained license agreement on the technology from Michigan Tech. This right was later transferred to the Westwood Land, Inc. A demonstration pilot plant is under construction to evaluate the technology. Steel industry will benefit from the new supply of the iron units once the commercial plants are constructed. Environmental benefits to the public and the steel industry will be tremendous. Not only the old piles of the slag will be removed, but also the federal responsible abandoned mines from the old mining activities can be remediated with the favorable product generated from the process. Cost can be reduced and there will be no lime required, which can avoid the release of carbon dioxide from lime production process.

J.Y. Hwang

2006-10-04

42

Effect of method of analysis on iron content of beef from advanced meat recovery systems.  

PubMed

A field survey was conducted by the USDA, Food Safety Inspection Service (FSIS) to provide analytical data on meat obtained from beef cervical vertebrae processed by advanced meat recovery (AMR) systems. As a result, an added iron performance standard was proposed to limit the amount of marrow in AMR products. The performance standard was based on iron content of hand boned lean compared to AMR lean. Iron content was determined by a hydrochloric wet ash digestion method. The same samples were then analyzed using dry ash digestion. The objectives of the study were to determine differences in iron content of the survey samples due to the digestion method and the impact of this difference on the added iron performance standard. Iron values by the dry ash method were approximately double those of the wet ash method. The difference was a result of incomplete volatilization of the organic matrix by hydrochloric acid in the wet ash procedure. The performance standards developed from the wet and dry ash methods were 1.8 and 3.2 mg added iron 100(-1) g, respectively. Added iron levels from the dry ash method greater than 3.2 mg 100(-1) g were present in 60% of the AMR lean indicating that some marrow was present or that factors other than amount of iron in hand boned lean should be considered before a performance standard is established. PMID:22062165

Windham, W R; Field, R A

2000-12-01

43

Effect of method of analysis on iron content of beef from advanced meat recovery systems  

Microsoft Academic Search

A field survey was conducted by the USDA, Food Safety Inspection Service (FSIS) to provide analytical data on meat obtained from beef cervical vertebrae processed by advanced meat recovery (AMR) systems. As a result, an added iron performance standard was proposed to limit the amount of marrow in AMR products. The performance standard was based on iron content of hand

W. R Windham; R. A Field

2000-01-01

44

Correlation of change in R2* and phase with putative iron content in deep gray matter of healthy adults  

PubMed Central

Purpose To establish a correlation between putative iron content using susceptibility weighted imaging (SWI) phase and T2* weighted magnitude values in the basal ganglia as a function of age in healthy human brains. Materials and methods 100 healthy adults (20-69 yr.; mean = 43 yr) were evaluated for this study using a gradient echo sequence. The original magnitude and high pass filtered phase data were analyzed as proxy variables for iron content in the substantia nigra, red nucleus, globus pallidus, putamen, caudate nucleus, thalamus and pulvinar thalamus. Each structure was broken into two parts, a high iron content region and a low iron content region. Results Both magnitude and phase data showed an increase in putative iron content with age. However, the high iron content region revealed two new pieces of information: both the average iron content per pixel and the area of high iron increased with age. Further, significant increase in iron uptake as a function of age was found past the age of 40. Conclusion A two region of interest analysis of iron is a much more sensitive means to evaluate iron content change over time. Contrary to the current belief that iron content increases level off with age, the putative iron deposition in region two is seen to increase with age.

Haacke, E. Mark; Miao, Yanwei; Liu, Manju; Habib, Charbel A.; Katkuri, Yashwanth; Liu, Ting; Yang, Zhihong; Lang, Zhijin; Hu, Jiani; Wu, Jianlin

2010-01-01

45

Iron content and its relations to the sulphur and titanium contents of epiphytic and terricolous lichens and pine bark in Finland.  

PubMed

The iron content was studied in the epiphytic lichens Hypogymnia physodes (L.) Nyl. and Pseudevernia furfuracea (L.) Zopf, in the terricolous lichens Cladina sp. and Peltigera aphthosa (L.) Willd., and in pine bark collected from 31 sites in Finland. There appeared to be differences between lichen species, epiphytes having generally higher concentrations. The iron content of H. physodes was highly significantly correlated (p<0.001) with its sulphur content, reflecting the relations of these elements in precipitation. The highly significant correlations between the iron and titanium contents indicated differences of the phorophytes. The iron/sulphur ratio of H. physodes on pine was 1.3 and on birch 1.4 and iron/titanium ratios were 10.4 and 11.3 respectively. The iron content of Cladina sp. showed highly significant parallel correlations (p<0.001) with its sulphur and titanium contents. The iron/titanium ratio decreased from 9.6 to 8.2 when the iron content increased by 95%, the sulphur content being equal. The iron/titanium ratio of Cladina sp. was nearly identical to that of P. furfuracea. The relation between iron and sulphur, and the fraction of soluble and insoluble iron in precipitation versus lichens and pine bark were considered. Special attention was paid in the discussion to differences in substrate: pine and birch bark for H. physodes, and soil for Cladina sp. PMID:15091708

Takala, K; Olkkonen, H; Salminen, R

1994-01-01

46

In-situ Characterization and Mapping of Iron Compounds in Alzheimer?s Tissue  

SciTech Connect

There is a well-established link between iron overload in the brain and pathology associated with neurodegeneration in a variety of disorders such as Alzheimer's (AD), Parkinson's (PD) and Huntington's (HD) diseases. This association was first discovered in AD by Goodman in 1953, where, in addition to abnormally high concentrations of iron in autopsy brain tissue, iron has also been shown to accumulate at sites of brain pathology such as senile plaques. However, since this discovery, progress in understanding the origin, role and nature of iron compounds associated with neurodegeneration has been slow. Here we report, for the first time, the location and characterization of iron compounds in human AD brain tissue sections. Iron fluorescence was mapped over a frontal-lobe tissue section from an Alzheimer's patient, and anomalous iron concentrations were identified using synchrotron X-ray absorption techniques at 5 {micro}m spatial resolution. Concentrations of ferritin and magnetite, a magnetic iron oxide potentially indicating disrupted brain-iron metabolism, were evident. These results demonstrate a practical means of correlating iron compounds and disease pathology in-situ and have clear implications for disease pathogenesis and potential therapies.

Collingwood, J.F.; Mikhaylova, A.; Davidson, M.; Batich, C.; Streit, W.J.; Terry, J.; Dobson, J. (IIT); (Keele); (Florida)

2008-06-16

47

[Evaluation of iron, zinc and copper contents in selected spices available on the Polish market].  

PubMed

The aim of the study was to evaluate the content of iron, zinc and copper in selected spices (pepper, parsley, dill, thyme, oregano, basil, marjoram, rosemary, juniper) from three companies. The contents of minerals were determined by flame AAS. Statistical analysis was carried out employing the STATISTICA software and using the ANOVA test. The high content of minerals was found in basil. Juniper contains relatively low quantities of these elements. It was shown a significant differences in iron, zinc and copper content in spices come from different companies. PMID:22171516

Suliburska, Joanna; Kaczmarek, Karolina

2011-01-01

48

Mapping and characterization of iron compounds in Alzheimer?s tissue  

SciTech Connect

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.

Collingwood, Joanna; Dobson, Jon (Keele)

2008-06-16

49

Serum protein, ascorbic acid & iron & tissue collagen in oral submucous fibrosis--a preliminary study.  

PubMed

A study of 36 patients with oral submucous fibrosis, revealed that all patients had the habit of chewing betel nut, pan masala or the traditional mixture (betel nut, betel leaf and lime) suggesting a link between fibrosis and arecanut. There was an increase in the globulin fraction of protein and hence a decreased A/G ratio in these patients. There was a significant increase in total protein levels possibly due to the increase in globulin fractions and other serum proteins. Ascorbate and iron levels decreased perhaps because of their utilisation in collagen synthesis. The total tissue collagen content increased significantly in patients with advanced disease and, it increased with the progression of the disease leading to hypomobility of the tongue, lips, cheeks, soft palate and faucial pillars. PMID:8225452

Anuradha, C D; Devi, C S

1993-06-01

50

In-Vitro Measurement of Iron Concentration in Human Hepatic Tissue by Magnetic Induction Methods.  

National Technical Information Service (NTIS)

This article studies the feasibility of a magnetic induction (MI) based system to measure the concentration of paramagnetic material in biological tissues. Our final objective is the measurement of hepatic iron overload with a non-invasive method. We have...

R. Casanyas H. Scharfetter A. Altes A. Remacha P. Sarda

2001-01-01

51

Determination of iron content in different parts of herbs used traditionally for anaemia treatment in East Africa.  

PubMed

The iron content in different parts of eight plants traditionally used to treat anaemia in Eastern Africa was determined using atomic absorption spectrophotometry. Extracts were made of plant samples using both wet and dry oxidation procedures. Results obtained from both procedures agree significantly and the average of both methods was taken as the iron content in each plant part. In most cases, the values obtained for the rootbark had a higher total iron content than the corresponding leaves and stembark. The prominent iron contents of 35.69 and 35.21 mg/100 g were found in the rootbark of Bridelia cathartica and Lannea stuhlmannii, respectively. The iron content of the decoctions prepared in the traditional way was low. However, the therapeutic potential of the herbs cannot be established on the basis of available iron content alone as other factors play a role in the absorption of iron in the body. PMID:9406897

Omolo, O J; Chhabra, S C; Nyagah, G

1997-10-01

52

Magnetic iron compounds in the human brain: a comparison of tumour and hippocampal tissue  

PubMed Central

Iron is a central element in the metabolism of normal and malignant cells. Abnormalities in iron and ferritin expression have been observed in many types of cancer. Interest in characterizing iron compounds in the human brain has increased due to advances in determining a relationship between excess iron accumulation and neurological and neurodegenerative diseases. In this work, four different magnetic methods have been employed to characterize the iron phases and magnetic properties of brain tumour (meningiomas) tissues and non-tumour hippocampal tissues. Four main magnetic components can be distinguished: the diamagnetic matrix, nearly paramagnetic blood, antiferromagnetic ferrihydrite cores of ferritin and ferrimagnetic magnetite and/or maghemite. For the first time, open hysteresis loops have been observed on human brain tissue at room temperature. The hysteresis properties indicate the presence of magnetite and/or maghemite particles that exhibit stable single-domain (SD) behaviour at room temperature. A significantly higher concentration of magnetically ordered magnetite and/or maghemite and a higher estimated concentration of heme iron was found in the meningioma samples. First-order reversal curve diagrams on meningioma tissue further show that the stable SD particles are magnetostatically interacting, implying high-local concentrations (clustering) of these particles in brain tumours. These findings suggest that brain tumour tissue contains an elevated amount of remanent iron oxide phases.

Brem, Franziska; Hirt, Ann M; Winklhofer, Michael; Frei, Karl; Yonekawa, Yasuhiro; Wieser, Heinz-Gregor; Dobson, Jon

2006-01-01

53

Content and binding forms of heavy metals, aluminium and phosphorus in bog iron ores from Poland.  

PubMed

Bog iron ores are widespread in Polish wetland soils used as meadows or pastures. They are suspected to contain high concentrations of heavy metals, which are precipitated together with Fe along a redox gradient. Therefore, soils with bog iron ore might be important sources for a heavy metal transfer from meadow plants into the food chain. However, this transfer depends on the different binding forms of heavy metals. The binding forms were quantified by sequential extraction analysis of heavy metals (Fe, Mn, Cr, Co, Ni, Cd, Pb) as well as Al and P on 13 representative samples of bog iron ores from central and southwestern Poland. Our results showed total contents of Cr, Co, Ni, Zn, Cd, and Pb not to exceed the natural values for sandy soils from Poland. Only the total Mn was slightly higher. The highest contents of all heavy metals have been obtained in iron oxide fractions V (occluded in noncrystalline and poorly crystalline Fe oxides) and VI (occluded in crystalline Fe oxides). The results show a distinct relationship between the content of Fe and the quantity of Zn and Pb as well P. Water soluble as well as plant available fractions were below the detection limit in most cases. From this we concluded bog iron ores not to be an actual, important source of heavy metals in the food chain. However, a remobilization of heavy metals might occur due to any reduction of iron oxides in bog iron ores, for example, by rising groundwater levels. PMID:19398508

Kaczorek, Danuta; Brümmer, Gerhard W; Sommer, Michael

2009-01-01

54

Quantification of melanin and iron content in uveal malignant melanomas and correlation with magnetic resonance image.  

PubMed Central

Eleven patients with uveal malignant melanomas (MM) were studied by magnetic resonance (MR) imaging before enucleation. The MR appearances varied, but often were different from those previously reported to be characteristic of these tumours. Using an image analyser to assess quantitatively the melanin and iron content of each tumour, a wide range of tumour melanin concentrations was found, but universally low tumour iron concentrations. These values were compared with MR appearances that were quantified and expressed as contrast to noise ratios. The correlation between T1 and T2 shortening and increasing melanin content did not reach statistical significance. There was no correlation between MR appearances and iron content. The theories postulated to explain the diverse MR appearances of uveal MMs are discussed and variations in tumour melanin content and differences in scanner strengths are suggested as the most likely explanations. Images

Ferris, J D; Bloom, P A; Goddard, P R; Collins, C

1993-01-01

55

Demonstration of iron and thorium in autopsy tissues by x-ray microanalysis  

SciTech Connect

We performed x-ray microanalysis of autopsy specimens using a scanning-transmission electron microscopy mode. Tissues were obtained at necropsy from a patient with history of angiography using thorium dioxide and from a patient with hemochromatosis. X-ray microanalysis confirmed the presence of thorium and iron in their respective tissues. Effects of staining reagents were examined.

Landas, S.; Turner, J.W.; Moore, K.C.; Mitros, F.A.

1984-03-01

56

Protein, calcium, iron, and amino acid content of selected wild and domesticated cultivars of finger millet.  

PubMed

Two wild and eight domesticated cultivars of finger millet were analyzed to determine their proximate composition and calcium, iron, and amino acid content. Wide variations were observed in the protein (mean values ranged from 7.5 to 11.7%), calcium (376 to 515 mg/100 g), and iron (3.7 to 6.8 mg/100 g) content of the wild and domesticated cultivars. A wild progenitor of finger millet, E coracana subsp. africana was significantly higher in protein than four of the six domesticated accessions analyzed. The calcium and iron content of the wild progenitor was also significantly greater than that of two domesticated cultivars. The wild species was also found to be higher in lysine and five other essential amino acids. These results indicate that the nutritional value of finger millet may be significantly improved by selective crossbreeding of the cereal's wild and domesticated cultivars. PMID:8475005

Barbeau, W E; Hilu, K W

1993-03-01

57

Water, nitrogen and lipides content of tissues of Varanus griseus, Daud  

Microsoft Academic Search

1.The contents of water, nitrogen and lipides of the different tissues of Varanus griseus Daud. are given.2.The values of water and nitrogen content of a tissue were found to be more or less constant if calculated on fat-free basis.3.Body fluids were found to contain the highest content of water. Nuclear tissues—with the exception of skin—were found to contain more water

Fouad Khalil; Guirguis Abdel-Messeih

1959-01-01

58

Iron content and acid phosphatase activity in hepatic parenchymal lysosomes of patients with hemochromatosis before and after phlebotomy treatment  

SciTech Connect

Lysosomal structures in liver parenchymal cells of 3 patients with iron overload and of 3 subjects without iron-storage disorders were investigated. A combination of enzyme cytochemistry--with cerium as a captive ion to demonstrate lysosomal acid phosphatase activity--and electron probe X-ray microanalysis (EPMA) was used. We were able (1) to define and quantify lysosomal structures as lysosomes, siderosomes, or residual bodies, (2) to quantify the amount of iron and cerium simultaneously in these structures, and (3) to evaluate a possible relation between iron storage and enzyme activity. With histopathologically increased iron storage, the number of siderosomes had increased at the cost of lysosomes, with a corresponding increase in acid phosphatase activity in both organelles. In histopahtologically severe iron overload, however, acid phosphatase activity was low or not detectable and most of the iron was stored in residual bodies. After phlebotomy treatment, the number of siderosomes had decreased in favor of the lysosomes, approaching values obtained in control subjects, and acid phosphatase activity was present in all iron-containing structures. In this way a relationship between iron storage and enzyme activity was established. The iron content of the individual lysosomal structures per unit area had increased with histopathologically increased iron storage and had decreased after phlebotomy treatment. From this observation, it is concluded that the iron status of the patient is not only reflected by the amount of iron-containing hepatocytes but, as well, by the iron content lysosomal unit area.

Cleton, M.I.; de Bruijn, W.C.; van Blokland, W.T.; Marx, J.J.; Roelofs, J.M.; Rademakers, L.H.

1988-03-01

59

EFFECTS OF IRON CONTENT IN COAL COMBUSTION FLY ASHES ON SPECIATION OF MERCURY  

EPA Science Inventory

The paper discusses the effects of iron content in coal combustion fly ashes on speciation of mercury. (NOTE: The chemical form of mercury species in combustion flue gases is an important influence on the control of mercury emissions from coal combustion). The study focused on th...

60

Correlation between the Iron, Magnesium, Potassium and Zinc Content in Adolescent Girls' Hair and Their Academic Records  

Microsoft Academic Search

Background: The aim of this study is to investigate the correlation between school acade- mic records and the iron, magnesium, potassium, and zinc content in adoles- cent girls' hair. Methods: The iron, magnesium, potassium, and zinc content in hair samples from 148 adolescent girls was determined by atomic absorption spectrometer. Their academic records from 2 school semesters were interrelated. Results:

Chin-Thin Wang; Yingjeng James Li; Fu-Jin Wang; Yi-Min Shi; Bee-Tsu Lee

61

Tensile Properties of Al-Cu 206 Cast Alloys with Various Iron Contents  

NASA Astrophysics Data System (ADS)

The Al-Cu 206 cast alloys with varying alloy compositions ( i.e., different levels of Fe, Mn, and Si) were investigated to evaluate the effect of the iron-rich intermetallics on the tensile properties. It is found that the tensile strength decreases with increasing iron content, but its overall loss is less than 10 pct over the range of 0.15 to 0.5 pct Fe at 0.3 pct Mn and 0.3 pct Si. At similar iron contents, the tensile properties of the alloys with dominant Chinese script iron-rich intermetallics are generally higher than those with the dominant platelet phase. In the solution and artificial overaging condition (T7), the tensile strength of the 206 cast alloys with more than 0.15 pct Fe is satisfactory, but the elongation does not sufficiently meet the minimum requirement of ductility (>7 pct) for critical automotive applications. However, it was found that both the required ductility and tensile strength can be reached at high Fe levels of 0.3 to 0.5 pct for the alloys with well-controlled alloy chemistry and microstructure in the solution and natural aging condition (T4), reinforcing the motivation for developing recyclable high-iron Al-Cu 206 cast alloys.

Liu, K.; Cao, X.; Chen, X.-G.

2014-05-01

62

A method for routine measurements of total sugar and starch content in woody plant tissues  

Microsoft Academic Search

Summary Several extraction and measurement methods cur- rently employed in the determination of total sugar and starch contents in plant tissues were investigated with the view to streamline the process of total sugar and starch determination. Depending on the type and source of tissue, total sugar and starch contents estimated from samples extracted with 80% hot ethanol were significantly greater

PAK S. CHOW; SIMON M. LANDHÄUSSER

63

Wheat (Triticum aestivum) NAM proteins regulate the translocation of iron, zinc, and nitrogen compounds from vegetative tissues to grain.  

PubMed

The NAM-B1 gene is a NAC transcription factor that affects grain nutrient concentrations in wheat (Triticum aestivum). An RNAi line with reduced expression of NAM genes has lower grain protein, iron (Fe), and zinc (Zn) concentrations. To determine whether decreased remobilization, lower plant uptake, or decreased partitioning to grain are responsible for this phenotype, mineral dynamics were quantified in wheat tissues throughout grain development. Control and RNAi wheat were grown in potting mix and hydroponics. Mineral (Ca, Cu, Fe, K, Mg, Mn, P, S, and Zn) and nitrogen (N) contents of organs were determined at regular intervals to quantify the net remobilization from vegetative tissues and the accumulation of nutrients in grain. Total nutrient accumulation was similar between lines, but grain Fe, Zn, and N were at lower concentrations in the NAM knockdown line. In potting mix, net remobilization of N, Fe, and Zn from vegetative tissues was impaired in the RNAi line. In hydroponics with ample nutrients, net remobilization was not observed, but grain Fe and Zn contents and concentrations remained lower in the RNAi line. When Fe or Zn was withheld post-anthesis, both lines demonstrated remobilization. These results suggest that a major effect of the NAM genes is an increased efflux of nutrients from the vegetative tissues and a higher partitioning of nutrients to grain. PMID:19858116

Waters, Brian M; Uauy, Cristobal; Dubcovsky, Jorge; Grusak, Michael A

2009-01-01

64

Effect of iron status on the absorption, speciation and tissue distribution of aluminium in rats  

NASA Astrophysics Data System (ADS)

Aluminium absorption, distribution and speciation in rats have been investigated by administering a single oral dose of 26Al to three groups of 10 Sprague-Dawley rats with the first group having normal, the second group having iron overloaded and the third group having iron deficient status before administration. The dose was 20 ng 26Al together with 200 ?g 27Al as AlCl 3. The rats were sacrificed 24 h after administration of 26Al. Samples of blood plasma, urine, femur, liver and spleen were taken. 26Al was measured in the samples with accelerator mass spectrometry. The group with iron deficiency had a larger intestinal uptake and higher concentrations in liver, spleen and plasma than the control group whereas iron overload decreased intestinal absorption and tissue concentrations of 26Al.

Winklhofer, C.; Steinhausen, C.; Beck, E.; Alvarez-Brückmann, M.; Kinzel, S.; Ittel, T.-H.; Nolte, E.

2000-10-01

65

Magnetic characterisation of rat muscle tissues after subcutaneous iron dextran injection.  

PubMed

Ex vivo freeze-dried rat muscle tissues, collected at different times t after a single dose of subcutaneously injected iron dextran, have been magnetically characterised. The AC susceptibility of the tissues shows an overall superparamagnetic behaviour and the dependence on t of, especially, the out-of-phase component is remarkably systematic despite the fact that each tissue originates in a different rat individual. The experiments show that the akaganéite (beta-FeOOH) nanoparticles contained in the injected drug are progressively degraded in the living tissue and, at times of the order of 1 month and for all the analysed rat individuals, converge to a magnetically well-defined species with much narrower magnetic activation energy distribution than iron dextran. Thorough transmission electron microscopy experiments of the same tissues indicate the presence of oxyhydroxide particles, whose size decreases for increasing t in agreement with the interpretation of the magnetic susceptibility. The conclusions drawn from the magnetic study do well correspond to the properties of the whole tissue since no biochemical extraction work has been done. The AC susceptibility appears to be a valuable and complementary tool in pharmacological studies of iron-containing drugs. PMID:15949712

Lázaro, F J; Abadía, A R; Romero, M S; Gutiérrez, L; Lázaro, J; Morales, M P

2005-06-10

66

Magnetic poly(?-caprolactone)/iron-doped hydroxyapatite nanocomposite substrates for advanced bone tissue engineering  

PubMed Central

In biomedicine, magnetic nanoparticles provide some attractive possibilities because they possess peculiar physical properties that permit their use in a wide range of applications. The concept of magnetic guidance basically spans from drug delivery and hyperthermia treatment of tumours, to tissue engineering, such as magneto-mechanical stimulation/activation of cell constructs and mechanosensitive ion channels, magnetic cell-seeding procedures, and controlled cell proliferation and differentiation. Accordingly, the aim of this study was to develop fully biodegradable and magnetic nanocomposite substrates for bone tissue engineering by embedding iron-doped hydroxyapatite (FeHA) nanoparticles in a poly(?-caprolactone) (PCL) matrix. X-ray diffraction analyses enabled the demonstration that the phase composition and crystallinity of the magnetic FeHA were not affected by the process used to develop the nanocomposite substrates. The mechanical characterization performed through small punch tests has evidenced that inclusion of 10 per cent by weight of FeHA would represent an effective reinforcement. The inclusion of nanoparticles also improves the hydrophilicity of the substrates as evidenced by the lower values of water contact angle in comparison with those of neat PCL. The results from magnetic measurements confirmed the superparamagnetic character of the nanocomposite substrates, indicated by a very low coercive field, a saturation magnetization strictly proportional to the FeHA content and a strong history dependence in temperature sweeps. Regarding the biological performances, confocal laser scanning microscopy and AlamarBlue assay have provided qualitative and quantitative information on human mesenchymal stem cell adhesion and viability/proliferation, respectively, whereas the obtained ALP/DNA values have shown the ability of the nanocomposite substrates to support osteogenic differentiation.

Gloria, A.; Russo, T.; D'Amora, U.; Zeppetelli, S.; D'Alessandro, T.; Sandri, M.; Banobre-Lopez, M.; Pineiro-Redondo, Y.; Uhlarz, M.; Tampieri, A.; Rivas, J.; Herrmannsdorfer, T.; Dediu, V. A.; Ambrosio, L.; De Santis, R.

2013-01-01

67

Correlation of natural gas content to iron species in the New Albany shale group  

USGS Publications Warehouse

Mo??ssbauer parameters were obtained for four Illinois Basin shales and their corresponding < 2??m clay fractions from wells drilled through the New Albany Shale Group in Henderson, Tazewell, and Effingham counties in Illinois and Christian County in Kentucky. Off-gas analysis indicated that the Illinois cores were in an area of low gas potential, while the Kentucky core was in an area of moderate-to-good potential. Iron-rich dolomite (ankerite) was found in the Kentucky core but not in the Illinois cores. In the Kentucky core, gas content could be correlated with the ankerite in the bulk sample, the Mo??ssbauer M (2) species in the clay fraction, and a ferrous iron species in the clay fraction. The location of the greatest concentration of natural gas in the Kentucky core could be predicted by following the changes in percentage concentration of these iron species when plotted against the depth of burial of the core sample. ?? 1981.

Shiley, R. H.; Cluff, R. M.; Dickerson, D. R.; Hinckley, C. C.; Smith, G. V.; Twardowska, H.; saporoschenko, M.

1981-01-01

68

Nitric oxide and glutathione impact the expression of iron uptake- and iron transport-related genes as well as the content of metals in A. thaliana plants grown under iron deficiency  

PubMed Central

Mounting evidence indicate that nitric oxide (NO) acts as a signaling molecule mediating iron deficiency responses through the upregulation of the expression of iron uptake-related genes. Accordingly, NO donors such as nitrosoglutathione (GSNO) were reported to improve the fitness of plants grown under iron deficiency. Here, we showed that glutathione, a by-product of GSNO, triggered the upregulation of the expression of iron uptake- and transport-related gene and an increase of iron concentration in Arabidopsis thaliana seedlings facing iron deficiency. Furthermore, we provided evidence that under iron deficiency, NO released by GSNO did not improve the root iron concentration but impacted the content of copper. Collectively, our data highlight the complexity of interpreting data based on the use of NO donors when investigating the role of NO in iron homeostasis.

Koen, Emmanuel; Szymanska, Katarzyna; Klinguer, Agnes; Dobrowolska, Grazyna; Besson-Bard, Angelique; Wendehenne, David

2012-01-01

69

The influence of carbon content in the borided Fe-alloys on the microstructure of iron borides  

Microsoft Academic Search

This paper presents the results of Electron Back-Scatter Diffraction (EBSD) analyses of the borided layers produced on substrate of varying carbon content. Two types of materials were investigated: borided Armco iron of very low carbon content and borocarburized chromium- and nickel-based steels of high carbon content beneath iron borides. The tetragonal phase Fe2B was identified in all materials studied. It

M.. Kulka; A.. Pertek; L.. Klimek

2006-01-01

70

Action of Amprolium on the Thiamine Content of Rat Tissues  

Microsoft Academic Search

A study was made of the action of Amprolium on rats raised with a thiamine-deficient diet. The animals were given supplements of thiamine alone or together with Amprolium, by the oral or parenteral route. The administration of thiamine alone resulted in an adequate thiamine level in the tissues. The simultaneous administration of thiamine and Amprolium prevented the establishment of normal

G. HINDI; G. FERRARI; U. VENTURA

71

Model near-infrared optical constants of olivine and pyroxene as a function of iron content  

Microsoft Academic Search

The imaginary coefficients of the complex index of refraction of olivine, low-Ca orthopyroxene, and high-Ca clinopyroxene are derived as a function of iron content and wavelength over the spectral region 0.4 to 2.5 tm from reflectance spectra of powders and Hapke radiative transfer theory. Reflectance spectra as a function of composition and grain size are computed and compared. I find

Paul G. Lucey

1998-01-01

72

Antioxidant status and mineral contents in tissues of rutin and baicalin fed rats  

Microsoft Academic Search

The versatile benefit effects of flavonoids lead some nutritionists to believe that they are micronutrients. However, excess intake of flavonoids may cause side effects. In this paper, the effects produced by a higher intake of rutin and baicalin on antioxidant status as well as trace minerals such as iron, copper and zinc in rat tissues were studied. When rats were

Zhonghong Gao; Huibi Xu; Xiaojun Chen; Hao Chen

2003-01-01

73

Protein content in irrigating solutions in contact with pulp tissue.  

PubMed

Endodontic irrigating solutions may have different effects, one of which is dissolving pulp tissue. The capacity of different irrigants to dissolve vital and necrotic pulp tissue was evaluated in vitro by means of a quantitative and qualitative study of total soluble pulp protein. Vital pulps and pulps with induced necrosis from young bovine teeth were used. Pulp was cut into smaller pieces, weighed and placed in 1 ml of 1% and 2.5% sodium hypochlorite, 1% and 5% calcium hydroxide, 0.2% chlorhexidine gluconate, 1% tea and distilled water as a control, and kept at 37 degrees. Samples of 20 microl were taken at 30 and 90 minutes and 20 hours. Total protein was dosed using the Lowry method and soluble protein bands were determined by electrophoresis (12% SDS-Page). The results were analyzed using Anova. Chemical analysis of the electrophoretic runs of bovine pulp protein showed that both concentrations of sodium hypochlorite and calcium hydroxide produce denaturation of proteins. No solvent action was found with chlorhexidine, tea or distilled water. PMID:18841748

de la Casa, María Luisa; Salas, María Mercedes; López, María Elena; Raiden, Guillermo

2008-01-01

74

Effect of starvation on contents of water, nitrogen and lipids of tissues of Varanus griseus, Daud  

Microsoft Academic Search

1.In Varanus, it was found that the most active tissues as the brain, spinal cord, lungs and heart show a negligible loss in their contents of nitrogen, water and lipids by starvation.2.All the other tissues of Varanus, other than those mentioned above, showed a noticable loss in their nitrogen and lipid content as a result of starvation.3.Starvation was followed by

Fouad Khalil; Guirguis Abdel-Messeih

1959-01-01

75

ZIP14 and DMT1 in the liver, pancreas, and heart are differentially regulated by iron deficiency and overload: implications for tissue iron uptake in iron-related disorders  

PubMed Central

The liver, pancreas, and heart are particularly susceptible to iron-related disorders. These tissues take up plasma iron from transferrin or non-transferrin-bound iron, which appears during iron overload. Here, we assessed the effect of iron status on the levels of the transmembrane transporters, ZRT/IRT-like protein 14 and divalent metal-ion transporter-1, which have both been implicated in transferrin- and non-transferrin-bound iron uptake. Weanling male rats (n=6/group) were fed an iron-deficient, iron-adequate, or iron-overloaded diet for 3 weeks. ZRT/IRT-like protein 14, divalent metal-ion transporter-1 protein and mRNA levels in liver, pancreas, and heart were determined by using immunoblotting and quantitative reverse transcriptase polymerase chain reaction analysis. Confocal immunofluorescence microscopy was used to localize ZRT/IRT-like protein 14 in the liver and pancreas. ZRT/IRT-like protein 14 and divalent metal-ion transporter-1 protein levels were also determined in hypotransferrinemic mice with genetic iron overload. Hepatic ZRT/IRT-like protein 14 levels were found to be 100% higher in iron-loaded rats than in iron-adequate controls. By contrast, hepatic divalent metal-ion transporter-1 protein levels were 70% lower in iron-overloaded animals and nearly 3-fold higher in iron-deficient ones. In the pancreas, ZRT/IRT-like protein 14 levels were 50% higher in iron-overloaded rats, and in the heart, divalent metal-ion transporter-1 protein levels were 4-fold higher in iron-deficient animals. At the mRNA level, ZRT/IRT-like protein 14 expression did not vary with iron status, whereas divalent metal-ion transporter-1 expression was found to be elevated in iron-deficient livers. Immunofluorescence staining localized ZRT/IRT-like protein 14 to the basolateral membrane of hepatocytes and to acinar cells of the pancreas. Hepatic ZRT/IRT-like protein 14, but not divalent metal-ion transporter-1, protein levels were elevated in iron-loaded hypotransferrinemic mice. In conclusion, ZRT/IRT-like protein 14 protein levels are up-regulated in iron-loaded rat liver and pancreas and in hypotransferrinemic mouse liver. Divalent metal-ion transporter-1 protein levels are down-regulated in iron-loaded rat liver, and up-regulated in iron-deficient liver and heart. Our results provide insight into the potential contributions of these transporters to tissue iron uptake during iron deficiency and overload.

Nam, Hyeyoung; Wang, Chia-Yu; Zhang, Lin; Zhang, Wei; Hojyo, Shintaro; Fukada, Toshiyuki; Knutson, Mitchell D.

2013-01-01

76

Effect of sulfite exposure on zinc, iron, and copper levels in rat liver and kidney tissues  

Microsoft Academic Search

Sulfite is a potentially toxic molecule that might enter the body via ingestion, inhalation, or injection. For cellular detoxification,\\u000a mammalians rely on sulfite oxidase to convert sulfite to sulfate. The purpose of this research was to determine the effect\\u000a of sulfite on zinc, iron, and copper levels in rat liver and kidney tissues. Forty normal and sulfite oxidase-deficient male\\u000a albino

Vural Kucukatay; Sebahat Turgut; Erdogan Kocamaz; Gulten Emmungil; Melek Bor-Kucukatay; Gunfer Turgut; Hakan Akca; Huseyin Bagci

2006-01-01

77

Magnetoacoustic imaging of magnetic iron oxide nanoparticles embedded in biological tissues with microsecond magnetic stimulation  

PubMed Central

We present an experimental study on magnetoacoustic imaging of superparamagnetic iron oxide (SPIO) nanoparticles embedded in biological tissues. In experiments, a large-current-carrying coil is used to deliver microsecond pulsed magnetic stimulation to samples. The ultrasound signals induced by magnetic forces on SPIO nanoparticles are measured by a rotating transducer. The distribution of nanoparticles is reconstructed by a back-projection imaging algorithm. The results demonstrated the feasibility to obtain cross-sectional image of magnetic nanoparticle targets with faithful dimensional and positional information, which suggests a promising tool for tomographic reconstruction of magnetic nanoparticle-labeled diseased tissues (e.g., cancerous tumor) in molecular or clinic imaging.

Hu, Gang; He, Bin

2012-01-01

78

The interaction of asbestos and iron in lung tissue revealed by synchrotron-based scanning X-ray microscopy  

PubMed Central

Asbestos is a potent carcinogen associated with malignant mesothelioma and lung cancer but its carcinogenic mechanisms are still poorly understood. Asbestos toxicity is ascribed to its particular physico-chemical characteristics, and one of them is the presence of and ability to adsorb iron, which may cause an alteration of iron homeostasis in the tissue. This observational study reports a combination of advanced synchrotron-based X-ray imaging and micro-spectroscopic methods that provide correlative morphological and chemical information for shedding light on iron mobilization features during asbestos permanence in lung tissue. The results show that the processes responsible for the unusual distribution of iron at different stages of interaction with the fibres also involve calcium, phosphorus and magnesium. It has been confirmed that the dominant iron form present in asbestos bodies is ferritin, while the concurrent presence of haematite suggests alteration of iron chemistry during asbestos body permanence.

Pascolo, Lorella; Gianoncelli, Alessandra; Schneider, Giulia; Salome, Murielle; Schneider, Manuela; Calligaro, Carla; Kiskinova, Maya; Melato, Mauro; Rizzardi, Clara

2013-01-01

79

X-ray microanalysis of electrolyte content of normal, preneoplastic, and neoplastic mouse mammary tissue  

Microsoft Academic Search

Intracellular sodium, chlorine, and potassium concentrations (mmol\\/kg dry weight) were determined by electron probe X-ray microanalysis of individual epithelial cells in freeze-dried 2-micrometer sections of mouse mammary tissue which were cut at -30 degrees. A model system was utilized in order to compare elemental content of cells from normal pregnant mammary tissue and preneoplastic and neoplastic mammary tissues from female

Nancy K. R. Smith; Sidra B. Stabler; Ivan L. Cameron; Daniel Medina

1981-01-01

80

Optimum wavelengths for measurement of blood hemoglobin content and tissue hydration by NIR spectrophotometry  

NASA Astrophysics Data System (ADS)

This paper examines non-invasive methods for absolute determination of the hemoglobin content of arterial blood and the water content of skin. Both methods are based on diffuse reflectance spectrophotometry in the near-infrared band (800 - 1600 nm). Separation of blood and background tissue spectra is accomplished by a technique similar to pulse oximetry, with the added feature that the set of measurement wavelengths is chosen to be sensitive to both hemoglobin and water concentration in the blood. Regressions performed on a simulated tissue spectra suggest that {1060, 1160, 1200 and 1320 nm} is an optimal set of wavelengths for measurement of tissue hydration and {1040, 1120, 1140 and 1200 nm} is an optimal set of wavelengths for measurement of hemoglobin content under typical measurement conditions. A simple in vitro tissue phantom whose optical properties can be altered in a controlled manner was developed to test the feasibility of the methods. Measurements were made with a custom-designed NIR spectrophotometer.

Kumar, Gitesh; Schmitt, Joseph M.

1996-05-01

81

Simultaneous Field and R2* Mapping to Quantify Liver Iron Content Using Autoregressive Moving Average Modeling  

PubMed Central

Purpose To investigate the use of a complex multi-gradient echo (mGRE) acquisition and an autoregressive moving average (ARMA) model for simultaneous susceptibility and R2* measurements for the assessment of liver iron content (LIC) in patients with iron overload. Materials and Methods Fifty MR exams with magnitude and phase mGRE images are processed using the ARMA model which provides fat-separated field maps, R2* maps, and T1-W imaging. The LIC is calculated by measuring the susceptibility between the liver and the right transverse abdominal muscle from the field maps. The relationship between LIC derived from susceptibility measurements and LIC from R2* measurements is determined using linear least squares regression analysis. Results LIC measured from R2* is highly correlated to the LIC from the susceptibility method (mg/g dry = 8.99 ± 0.15 × (mg Fe/ml of wet liver) ?2.38 ± 0.29, R2=0.94). The field inhomogeneity in the liver is correlated with R2* (R2=0.85). Conclusion By using the ARMA model on complex mGRE images, both susceptibility and R2*-based LIC measurements can be made simultaneously. The susceptibility measurement can be used to help verify R2* measurements in the assessment of iron overload.

Taylor, Brian A.; Loeffler, Ralf B.; Song, Ruitian; McCarville, Mary E.; Hankins, Jane S.; Hillenbrand, Claudia M.

2011-01-01

82

Hot Tear Susceptibility of Al-Mg-Si-Fe Alloys with Varying Iron Contents  

NASA Astrophysics Data System (ADS)

Hot tear susceptibility in cast Al-0.52Si-0.34Mg- xFe 6060 aluminum alloys was investigated using a hot tearing test apparatus to simulate hot tearing in DC casting. The test apparatus has two cast bars, one that is used to measure the load response and one which is fixed at both ends to restrain thermal contraction so that hot tearing can be observed and rated where it occurred. The iron (Fe) content, ranging from 0.02 to 0.5 wt pct, was seen to have a major influence on the load response during solidification and the tear rating of these alloys. The findings are discussed in terms of Rappaz-Drezet-Gremaud (RDG) model sensitivity analysis and related to the effect of Fe content on the morphology and prevalence of the ?-Al5FeSi and ?-AlFeSi intermetallic phases and their influence on the coherency and coalescence of the microstructure.

Sweet, Lisa; Easton, Mark A.; Taylor, John A.; Grandfield, John F.; Davidson, Cameron J.; Lu, Liming; Couper, Malcolm J.; StJohn, David H.

2013-12-01

83

Mössbauer analysis of Nd-Co M-type strontium hexaferrite powders with different iron content  

NASA Astrophysics Data System (ADS)

The structural analysis of strontium hexaferrites SrFe x O19 (for x = 12, 11 and 10) and substituted samples Sr0.7Nd0.3Fe12 - y Co0.3O19 (for y = 0.3,1.3 and 2.3) prepared through the citrate precursor method is shown. Nd and Co substitution modifies saturation magnetization ( M S ) and increases coercivity ( H c ) in samples heat-treated at 1100°C for two hours. Mössbauer analyses show different iron occupancy and the influence of the Fe3 + content is particularly emphasized. Hematite segregation is observed for some compositions. Samples with low Fe3 + content show the best magnetic properties with no secondary phase segregation.

Herme, Carlos; Jacobo, Silvia E.; Bercoff, Paula G.; Arcondo, Bibiana

2010-01-01

84

Nitrite induces the extravasation of iron oxide nanoparticles in hypoxic tumor tissue.  

PubMed

Nitrite undergoes reconversion to nitric oxide under conditions characteristic of the tumor microenvironment, such as hypoxia and low pH. This selective conversion of nitrite into nitric oxide in tumor tissue has led to the possibility of using nitrite to enhance drug delivery and the radiation response. In this work, we propose to serially characterize the vascular response of brain tumor-bearing rats to nitrite using contrast-enhanced R2 * mapping. Imaging is performed using a multi-echo gradient echo sequence at baseline, post iron oxide nanoparticle injection and post-nitrite injection, whilst the animal is breathing air. The results indicate that nitrite sufficiently increases the vascular permeability in C6 gliomas, such that the iron oxide nanoparticles accumulate within the tumor tissue. When animals breathed 100% oxygen, the contrast agent remained within the vasculature, indicating that the conversion of nitrite to nitric oxide occurs in the presence of hypoxia within the tumor. The hypoxia-dependent, nitrite-induced extravasation of iron oxide nanoparticles observed herein has implications for the enhancement of conventional and nanotherapeutic drug delivery. PMID:24470164

Mistry, Nilesh; Stokes, Ashley M; Gambrell, James Van; Quarles, Christopher Chad

2014-04-01

85

Lead content of neuromuscular tissue in amyotrophic lateral sclerosis: case report and other considerations  

PubMed Central

Petkau, A., Sawatzky, A., Hillier, C. R., and Hoogstraten, J. (1974).British Journal of Industrial Medicine,31, 275-287. Lead content of neuromuscular tissue in amyotrophic lateral sclerosis. Case report and other considerations. In a case of amyotrophic lateral sclerosis, in which the occupational history and laboratory evidence indicated that exposure to lead had occured, it was found at necropsy that in tissues of nerve, spinal cord, and cardiac and skeletal muscle the lead content was 9·6 ± 0·3, 9·9 ± 1·7, 17·7, and 21·1 ± 5·1 ?g/g of dry weight of tissue, respectively. Significantly elevated levels of lead were also found at necropsy in nerve, spinal cord, and muscle tissue in other cases of amyotrophic lateral sclerosis that had not been exposed to lead during life. A reassessment of the role of lead in amyotrophic lateral sclerosis is indicated. Images

Petkau, A.; Sawatzky, A.; Hillier, C. R.; Hoogstraten, J.

1974-01-01

86

Iron  

Microsoft Academic Search

Iron poisoning causes its metabolic effects in proportion to the concentrations of free iron. Toxicity is therefore related to dose ingested. The amount of iron in different salts varies, and iron concentrations may rise and fall, making plasma concentrations difficult to interpret in acute poisoning. Clinical features include severe gastrointestinal irritation, cardiovascular collapse and direct organ damage to liver and

D. Nicholas Bateman

2007-01-01

87

Caffeic acid protects tissue antioxidants and DNA content in methamphetamine induced tissue toxicity in Sprague Dawley rats.  

PubMed

Caffeic acid (CA) (3,4-dihydroxycinnamic acid) is among the major hydroxycinnamic acids. Hydroxycinnamic acid is the major subgroup of phenolic compounds. Methamphetamine (METH) is a potent addictive psychostimulant. Chronic use and acute METH intoxication can cause substantial medical consequences, including spleen, kidney, liver and heart. The objective of the present study was to evaluate the antioxidant activity of CA to protect against oxidative stress and DNA damage to various organs in METH toxicity. Thirty-two male Sprague Dawley (SD) rats were divided into four equal groups: group 1 was injected (i.p) with saline (1 mL/kg) while groups 2,3 and 4 were injected (i.p) with METH (10 mg/kg) twice a day over five days period. Where 100 & 200 mg/kg of CA were injected (i.p) into groups 3 and 4, respectively one day before exposure to METH injections. Tissue antioxidants and DNA content were evaluated in different tissues. METH decreased glutathione (GSH) and glutathione peroxidase (GPx) levels while increased malondialdehyde (MDA), catalase (CAT) and protein carbonyl levels in brain (hypothalamus), liver, and kidney tissues of rats. METH increased hyperdiploidy in these tissues and DNA damage results. Prior treatment of CA to animals exposed to METH restores the above parameters to the normal levels and preserves the DNA content of these tissues. These results were supported by histopathological investigations. In conclusion, METH induced oxidative stress and DNA damage and pretreatment of CA before METH injections prevented tissue oxidative stress and DNA damage in METH-treated animals. PMID:22992185

Koriem, Khaled M M; Abdelhamid, Abdelhamid Z; Younes, Hady F

2013-02-01

88

The influence of carbon content in the borided Fe-alloys on the microstructure of iron borides  

SciTech Connect

This paper presents the results of Electron Back-Scatter Diffraction (EBSD) analyses of the borided layers produced on substrate of varying carbon content. Two types of materials were investigated: borided Armco iron of very low carbon content and borocarburized chromium- and nickel-based steels of high carbon content beneath iron borides. The tetragonal phase Fe{sub 2}B was identified in all materials studied. It was difficult to obtain an EBSD pattern from iron boride (FeB) because of its presence at low depths below the surface, and because of the rounded corners of the specimens. EBSD provided information on the orientation of Fe{sub 2}B crystals. In case of the low-carbon Armco iron the crystallographic orientation was constant along the full length of the Fe{sub 2}B needle. The EBSPs obtained from borocarburized steel indicate that the crystallographic orientation of the Fe{sub 2}B phase changes along the length of the needle. This is the result of hindered boron diffusion due to boriding of the carburized substrate. The increased resistance to friction wear of borocarburized layers arises from two reasons. One is the decreased microhardness gradient between the iron borides and the substrate, which causes a decrease in the brittleness of the iron borides and an improved distribution of internal stresses in the diffusion layer. The second is the changeable crystallographic orientation of iron borides, which leads to the lower texture and porosity of borided layers. These advantageous properties of the borocarburized layer can be obtained if the carbon content beneath the iron borides is no more than about 1.0-1.2 wt.% C.

Kulka, M. [Poznan University of Technology, Institute of Materials Science and Engineering, Pl. M.Sklodowskiej-Curie 5, 60-965 Poznan (Poland)]. E-mail: coolka@sol.put.poznan.pl; Pertek, A. [Poznan University of Technology, Institute of Materials Science and Engineering, Pl. M.Sklodowskiej-Curie 5, 60-965 Poznan (Poland)]. E-mail: pertek@sol.put.poznan.pl; Klimek, L. [Technical University of Lodz, Institute of Materials Science and Engineering, Stefanowskiego St.1/15, 90-924 Lodz (Poland)]. E-mail: kemilk@p.lodz.pl

2006-04-15

89

[Effect of parenteral nutrition on the nucleic acid content in normal rat tissues and in thyrotoxicosis].  

PubMed

The content of nucleic acids in tissues of healthy animals and those suffering from thyrotoxicosis was studied as affected by parenteral administration of amino acid mixture of moriamine S-2 and casein hydrolysate. The content of RNA in the skeletal muscles, heart and liver is established to change considerably under the effect of nitrogenous media. With administration of moriamine S-2 or caseine hydrolysate the higher level of RNA in tissues with thyrotoxicosis, is normalized, especially in the skeletal muscles. The character of changes depends essentially on properties and composition of the administered preparations. PMID:411201

Hlanz, R M; Skovrons'ka, E V; Vovk, H P

1977-01-01

90

Uptake and Tissue Content of Fatty Acids in Dog Myocardium under Normoxic and Ischemic Conditions  

Microsoft Academic Search

SUMMARY. The effect of ischemia on the myocardial content of nonesterified fatty acids (NEFA), triacylglycerol, cholesteryl esters, and phospholipids assayed with gas-liquid chromatography was studied in an open-chest dog preparation. Ischemia was induced by partial occlusion of the left interventricular coronary artery during 120 minutes (n=20). Tissue content of the lipid classes was assessed in biopsies taken from ischemic and

G. J. van der Vusse; F. W. Prinzen; W. A. Coumans; R. S. Reneman

91

Effect of varying iron content on the transport properties of the potassium-intercalated iron selenide KxFe2-ySe2  

NASA Astrophysics Data System (ADS)

We report the successful growth of high-quality single crystals of potassium-intercalated iron selenide KxFe2-ySe2 by the Bridgman method. The effect of iron vacancies on transport properties was investigated by electrical resistivity measurement. With varying iron content, the system passes from a semiconducting or insulating state to a superconducting state. Compared with superconductivity, the anomalous “hump” effect in the normal-state resistivity is much more sensitive to the iron deficiency. The electrical resistivity exhibits a perfect metallic behavior (R300K/R35K?42) for the sample with little iron vacancies. Our results suggest that the anomalous hump effect in the normal-state resistivity may be due to the ordering process of the cation vacancies in this nonstoichiometric compound rather than to a magnetic or structure transition. A trace of superconductivity extending up to near 44 K was also detected in some crystals of KxFe2-ySe2, which has the highest Tc of the reported iron selenides.

Wang, D. M.; He, J. B.; Xia, T.-L.; Chen, G. F.

2011-04-01

92

Content of lipids in blood and tissues of animals during hypodynamia  

NASA Technical Reports Server (NTRS)

Experiments on 97 rats and 50 rabbits were undertaken to study the influence of hypodynamia on the lipid content in the blood, liver, heart, and in the aorta. Reduction of muscular activity contributed to the increase of cholesterol and beta lipoprotein levels in the blood and to accumulation of cholesterol in the liver and the heart. The total lipid content in these tissues decreased. In the aorta the total lipid content increased, while lecithin and cephalin figures went down. The character of biochemical changes in hypodynamia resembles in many ways the lipid metabolism changes in atherosclerosis.

Federov, I. V.; Rylnikov, Y. P.; Lobova, T. M.

1980-01-01

93

A role for iron and oxygen chemistry in preserving soft tissues, cells and molecules from deep time.  

PubMed

The persistence of original soft tissues in Mesozoic fossil bone is not explained by current chemical degradation models. We identified iron particles (goethite-?FeO(OH)) associated with soft tissues recovered from two Mesozoic dinosaurs, using transmission electron microscopy, electron energy loss spectroscopy, micro-X-ray diffraction and Fe micro-X-ray absorption near-edge structure. Iron chelators increased fossil tissue immunoreactivity to multiple antibodies dramatically, suggesting a role for iron in both preserving and masking proteins in fossil tissues. Haemoglobin (HB) increased tissue stability more than 200-fold, from approximately 3 days to more than two years at room temperature (25°C) in an ostrich blood vessel model developed to test post-mortem 'tissue fixation' by cross-linking or peroxidation. HB-induced solution hypoxia coupled with iron chelation enhances preservation as follows: HB + O2 > HB - O2 > -O2 > +O2. The well-known O2/haeme interactions in the chemistry of life, such as respiration and bioenergetics, are complemented by O2/haeme interactions in the preservation of fossil soft tissues. PMID:24285202

Schweitzer, Mary H; Zheng, Wenxia; Cleland, Timothy P; Goodwin, Mark B; Boatman, Elizabeth; Theil, Elizabeth; Marcus, Matthew A; Fakra, Sirine C

2014-01-22

94

TISSUE REMODELING IN THE HUMAN LUNG IN RELATION TO PARTICLE CONCENTRATION AND METAL CONTENT  

EPA Science Inventory

TISSUE REMODELING IN THE HUMAN LUNG IN RELATION TO PARTICLE CONCENTRATION AND METAL CONTENT. J Gallagher1, J Inmon1, S Schlaegle2, A Levine2, T Rogers3, J Scott1, F Green4, M Schenker5, K Pinkerton5 1NHEERL, US-EPA, RTP, NC, USA; 2RJ Lee Group Inc, Monroeville, Pa, USA; ...

95

Nuclear Magnetic Resonance Relaxation and Water Contents in Normal Tissues and Five Types of Cancer Cells.  

National Technical Information Service (NTIS)

By studying NMR water proton spin lattice relaxation times (T1) of normal mouse and rat tissues at varying water contents and by comparing the data obtained with similar data obtained from 5 strains of pure cancer cells, we reached the conclusion that dif...

G. N. Ling M. Tucker

1983-01-01

96

Anserine and carnosine contents in muscular tissue of rat and rabbit.  

PubMed

The effect of various muscle conditions on anserine and carnosine contents suggests that these peptides have some physiological role in muscular functions. These conditions are: 1) Although the anserine content in rat gastrocnemius muscle was not changed by ischiamic denervation, the carnosine content was significantly decreased. Carnosinase activity in the denerved gastrocnemius muscle was two times stronger than that of intact gastrocnemius muscle. 2) Carnosine content in rat gastrocnemius muscle was also decreased by forced swimming exercise. 3) Neither anserine nor carnosine was detected in sarcoma and granuloma. 4) In rabbit, anserine and carnosine contents in white muscle fibers were 12-17 and 1-2 mumole/g of wet tissue and were approximately 10 and 2 times more than those in red muscle fibers, respectively. PMID:915561

Tamaki, N; Nakamura, M; Harada, M; Kimura, K; Kawano, H

1977-01-01

97

Effects of iron supplementation on red blood cell hemoglobin content in pregnancy  

PubMed Central

Although a mild degree of anemia is common in the third trimester of pregnancy, it remains a challenge to establish whether a decrease in hemoglobin (Hb) concentration is physiological or pathological. The World Health Organization suggested a Hb concentration of 110 g/L to discriminate anemia. Several European investigators recommended Hb cut-off values of between 101–110 g/L. The aim of this study was to establish short-term effects of iron supplementation on the hemoglobin content of reticulocytes (Ret-He) and red blood cells (RBC-He) in case of suspected iron deficient erythropoiesis (IDE) in the third trimester of pregnancy. Twenty-five subjects with suspected IDE during pregnancy (Hb ?110g/L, Ret-He <29.6 pg, zinc protoporphyrin >75 mol/mol hem) participated in the study. After iron supplementation, reticulocyte counts increased from 0.061±0.015×1012/L to 0.079±0.026×1012/L and Ret-He increased from 23.6±2.8 pg to 28.3±2.6 pg (P=<0.001). RBC-He increased from 26.9±1.9 pg to 27.4±1.8 pg (not significant, NS) and Ret-He/RBC-He ratio increased from 0.97±0.06 towards 1.07±0.05 (P=<0.001). Hb concentrations demonstrated an obvious increase from 105±6 g/L towards 115±5 g/L (P?0.001) after supplementation. An obvious increase in RBC distribution width was observed from 45.0±3.6 fL towards 52.3±7.0 fL (P?0.001). We recommend that Ret-He and Ret-He/RBC-He ratio be integrated into the protocols for anemia screening and for monitoring effects of iron supplementation during pregnancy. In particular, the parameters should be considered in subjects with Hb results in the controversial range of 101–108 g/L.

Schoorl, Margreet; Schoorl, Marianne; van der Gaag, Derek; Bartels, Piet C. M.

2012-01-01

98

Effect of Water and Iron Content on the Rheological Behavior of Olivine  

NASA Astrophysics Data System (ADS)

We have undertaken an experimental investigation of the effect of water and iron content on the viscosity of aggregates of Fe-Mg olivine in order to provide a basis for conparing convection models for the mantle of Earth with those for the more iron-rich mantle of Mars. Our study builds on three experimental observations: (i) At a given temperature, the viscosity of single crystals of San Carlos olivine [Fo90 = (Fe0.1Mg0.9)2SiO4] is signficantly higher than that of crystals of fayalite, Fo0, (ii) the viscosity of San Carlos olivine decreases with increasing water concentration, and (iii) the solubility of water in olivine increases with increasing iron concentration. To extend deformation experiments to polycrystalline samples of olivine of higher Fe content, powders of Fo50 and Fo70 were fabricated from mixtures of natural olivine, Fo90, and synthetic fayalite, Fo0. The resulting materials were ground into fine (<10 ? m) powders, cold-pressed into Ni capsules, and then hot-pressed at 300 MPa and 1533 K for 2 to 12 h. For experiments under hydrous conditions, two drops of water, each ˜0.03 ml, were added before sealing a sample within telescoping Ni cans for deformation. The average grain size of the resultant hot-pressed samples were between 20 and 57 ? m . In the samples deformed under hydrous conditions, water bubbles were present both within olivine grains and along grain boundaries, demonstrating that the samples were water-saturated. High-temperature, high-pressure compressive creep experiments in both the diffusion and the dislocation creep regimes were carried out using a gas-medium apparatus at temperatures of 1223 to 1473 K and a confining pressure of 300 MPa. Under both anhydrous and hydrous conditions, the viscosity of samples of Fo50 is a factor of >10 lower than the viscosity of samples of Fo70, which is a factor of >10 lower than the viscosity of samples of Fo90. The viscosity of a sample of a specific Fe:Mg ratio deformed under hydrous conditions is a factor of ˜10 lower than its counterpart deformed under anhydrous conditions. Therefore, at the same thermodynamic conditions (e.g., P, T, water fugacity), the viscosity of the more Fe-rich mantle ( ˜18 wt % FeO) of Mars will be a factor of ˜3 lower than the mantle ( ˜8 wt % FeO) of Earth.

Zimmerman, M. E.; Zhao, Y.; Kohlstedt, D. L.

2004-12-01

99

Tissue iron evaluation in chronically transfused children shows significant levels of iron loading at a very young age.  

PubMed

Chronic blood transfusions start at a very young age in subjects with transfusion-dependent anemias, the majority of whom have hereditary anemias. To understand how rapidly iron overload develops, we retrospectively reviewed 308 MRIs for evaluation of liver, pancreatic, or cardiac iron in 125 subjects less than 10 years old. Median age at first MRI evaluation was 6.0 years. Median liver iron concentrations in patients less than 3.5 years old were 14 and 13 mg/g dry weight in thalassemia major (TM) and Diamond-Blackfan anemia (DBA) patients, respectively. At time of first MRI, pancreatic iron was markedly elevated (> 100 Hz) in DBA patients, and cardiac iron ( R?* >50 Hz) was present in 5/112 subjects (4.5%), including a 2.5 years old subject with DBA. Five of 14 patients (38%) with congenital dyserythropoietic anemia (CDA) developed excess cardiac iron before their 10th birthday. Thus, clinically significant hepatic and cardiac iron accumulation occurs at an early age in patients on chronic transfusions, particularly in those with ineffective or absent erythropoiesis, such as DBA, CDA, and TM, who are at higher risk for iron cardiomyopathy. Performing MRI for iron evaluation in the liver, heart, and pancreas as early as feasible, particularly in those conditions in which there is suppressed bone marrow activity is very important in the management of iron loaded children in order to prescribe appropriate chelation to prevent long-term sequelae. . PMID:23861216

Berdoukas, Vasilios; Nord, Anne; Carson, Susan; Puliyel, Mammen; Hofstra, Thomas; Wood, John; Coates, Thomas D

2013-11-01

100

The importance of carbon content beneath iron borides after boriding of chromium and nickel-based low-carbon steel  

NASA Astrophysics Data System (ADS)

The complex (B+C) diffusion layers have been formed on chromium- and nickel-based low-carbon steels. Gas boriding applied to these steels that have been previously carburized enables the production of wear-resistant borocarburized layers. After combined surface hardening with boron and carbon in the microstructure two zones have been observed: iron borides (FeB+Fe 2B) and carburized zones. The iron borides in borocarburized layer show the tendencies towards lose of the needle-like nature. The depth of iron borides zone depend on pre-carburizing parameters. Although borocarburizing causes reducing of the depth of iron borides zone, it also reduces the microhardness gradient across the case. An increase of distance from the surface is accompanied by a gradual decrease of carbon content and microhardness in carburized zone. Probably, the brittleness of borocarburized layer is lower. In the consequence, the frictional wear resistance of borocarburized layers is essentially higher than that obtained in case of only borided layers. There is every indication that the carbon content beneath iron borides has an important effect on wear resistance, too. The highest wear resistance of borocarburized layer has been observed in case of about 1.2% C below iron borides.

Kulka, M.; Pertek, A.

2003-05-01

101

Effect of pretreatment of oak bark to develop porosity in the cell tissue on subsequent iron-catalysed hydrogasification  

Microsoft Academic Search

Oak bark was immersed in boiling water or extracted with supercritical carbon dioxide in the presence of water to develop porosity in the cell tissue before iron catalyst was loaded by wet impregnation. The iron-loaded bark was carbonized at 500°C, and the resulting char was hydrogasified in a thermobalance to measure the reactivity by the temperature-programmed method. The reactivity up

Tsutomu Suzuki; Minoru Funaki; Kenji Tanaka; Noriyasu Okazaki; Tetsuo Yamada

1996-01-01

102

The role of nickel content and the magnetic remanence in iron-nickel alloys of lunar composition  

NASA Technical Reports Server (NTRS)

Lunar samples are magnetic primarily due to the body centered cubic (BCC) iron and iron-nickel alloys they contain. Presented for the first time are results which demonstrate that the magnitude of the martensitic thermal remanence (MTRM) induced on quenching iron-nickel alloy in the geomagnetic field depends on the nickel content of the alloy. High magnetic stability is due to the increasing dislocation density and increasingly complex microstructures associated with increasing nickel content in the alloys. The results agree with the mechanical and structural properties of the alloys. The characteristic quench martensite microstructure observed on metallographic examination provides a recognition criterion for the MTRM mechanism. These results are important for lunar and meteoritic research intending to ascertain the paleofield responsible for the observed remanent magnetization.-

Wasilewski, P.

1974-01-01

103

A method for routine measurements of total sugar and starch content in woody plant tissues.  

PubMed

Several extraction and measurement methods currently employed in the determination of total sugar and starch contents in plant tissues were investigated with the view to streamline the process of total sugar and starch determination. Depending on the type and source of tissue, total sugar and starch contents estimated from samples extracted with 80% hot ethanol were significantly greater than from samples extracted with a methanol:chloroform:water solution. The residual ethanol did not interfere with the sugar and starch determination, rendering the removal of ethanol from samples unnecessary. The use of phenol-sulfuric acid with a phenol concentration of 2% provided a relatively simple and reliable colorimetric method to quantify the total soluble-sugar concentration. Performing parallel sugar assays with and without phenol was more useful for accounting for the interfering effects of other substances present in plant tissue than using chloroform. For starch determination, an enzyme mixture of 1000 U alpha-amylase and 5 U amyloglucosidase digested starch in plant tissue samples more rapidly and completely than previously recommended enzyme doses. Dilute sulfuric acid (0.005 N) was less suitable for starch digestion than enzymatic hydrolysis because the acid also broke down structural carbohydrates, resulting in overestimates of starch content. After the enzymatic digestion of starch, the glucose hydrolyzate obtained was measured with a peroxidase-glucose oxidase/o-dianisidine reagent; absorbance being read at 525 nm after the addition of sulfuric acid. With the help of this series of studies, we developed a refined and shortened method suitable for the rapid measurement of total sugar and starch contents in woody plant tissues. PMID:15294759

Chow, Pak S; Landhäusser, Simon M

2004-10-01

104

Effect of Carbon Content on Friction and Wear of Cast Irons.  

National Technical Information Service (NTIS)

Friction and wear experiments were conducted with cast irons and wrought steels containing various amounts of carbon in the alloy structure in contact with 52100 steel. Gray cast irons were found to exhibit lower friction and wear characteristics than whi...

D. H. Buckley

1977-01-01

105

Independence of in vitro iron absorption from mucosal transferrin content in rat jejunal and ileal segments  

Microsoft Academic Search

Isolated non blood-perfused intestinal segments from normal and irondeficient rats were used in vitro. A modification of the luminal perfusion method according to Fisher and Parsons allowed the comparison of iron and transferrin quantities in the serosal fluid at 15 min intervals. Iron transfer in jejunal and ileal segments was directly proportional to the luminal iron concentration within a dose

K. Schtimann; K. Osterloh; W. Forth

1986-01-01

106

[Fatty acid content of the lipid fraction of the liver and fatty tissues of fattened geese].  

PubMed

The content of fatty acids in the lipid fraction of the liver and in the body fats of fattened gray Landen geese. Determinations were carried out with a gas chromatography Chrom 41 supplied with Determinations were carried out with a gas chromatograph Chrom 41 supplied with a flame-ionization detector. It was found that the average content of fatty acids (saturated and unsaturated) as expressed by percent of their total amount was 45.90% and 54.10% (liver), 36.58% and 63.42% (subcutaneous fatty tissue), 42.79% and 57.31% (inner lard), and 39.01% and 60.99% (skin fats). PMID:3727379

Kostadinov, K; Monov, G

1986-01-01

107

Histamine content of peritoneal and tissue mast cells of growing rats  

Microsoft Academic Search

The histamine and 5-hydroxytryptamine (5-HT) content of mast cells was measured in rat peritoneal mast cells (isolated by density-gradient centrifugation or in crude peritoneal cell suspensions) and in some solid, mast-cell-rich tissues (tongue, skin, and duodenum). The duodenum contains large numbers of mast cells belonging to the specific type of mucosal mast cell. The peritoneal cavity, tongue, and skin contains

L. Enerbäck; U. Wingren

1980-01-01

108

Quantitative determination of the melanin contents in ocular tissues from human blue and brown eyes.  

PubMed

This paper deals with our findings on the quantities of melanin in the tissues from blue and brown eyes. The amount of melanin in the iris, ciliary body and retinal pigment epithelium-choroid was separately determined. The results are expressed as the amount of melanin in mg tissue as well as the amount of melanin in the whole tissue. The results showed that there was no statistically significant difference between the melanin content of the iris in blue and brown eyes. However the ciliary body and retinal pigment epithelium-choroid from brown eyes had more melanin than the corresponding tissues from blue eyes. Blue and brown eyes with higher colour intensity had more melanin than the corresponding eyes with lesser intensity of colour. It is suggested that the differences between brown and blue eyes in their melanin content may have relevance to the pharmacokinetics of drugs that bind to melanin. This would mean that the larger amounts of melanin would decrease the initial levels of the drugs and would increase the drug levels after prolonged periods. PMID:1402293

Menon, I A; Wakeham, D C; Persad, S D; Avaria, M; Trope, G E; Basu, P K

1992-01-01

109

Effect of dietary iron deficiency on mineral levels in tissues of rats  

Microsoft Academic Search

To clarify the influence of iron deficiency on mineral status, the following two synthetic diets were fed to male Wistar rats:\\u000a a control diet containing 128 ?g iron\\/g, and an iron-deficient diet containing 5.9 ?g iron\\/g. The rats fed the iron-deficient\\u000a diet showed pale red conjunctiva and less reactiveness than the rats fed the control diet. The hemoglobin concentration and

Katsuhiko Yokoi; Mieko Kimura; Yoshinori Itokawa

1991-01-01

110

High-strain shear deformation of olivine aggregates with different iron contents  

NASA Astrophysics Data System (ADS)

High-strain deformation experiments were conducted at high temperature and high pressure on olivine aggregates with two different iron contents in order to investigate both the mechanical behavior and the microstructural development. Torsion experiments were conducted in a gas-medium deformation apparatus under anhydrous conditions to shear strains of ~4 at a constant angular velocity, a temperature of 1473K, and a confining pressure of 300MPa. The compositions of the aggregates were Fo50 and Fo70. The applied shear strain rate ranged from 10-4 to 10^{-5} s-1, yielding shear stresses supported by the sample of ~100 MPa. To examine microstructural development, a series of parallel sections were examined. The first section was cut near the outside margin and the last section was cut along the central plane of the cyllindrical sample. Olivine samples deformed in the dislocation creep regime strain weakened before approaching steady state. A strong lattice preferred orientation (LPO) dominated the microstructure along with significant grain flattening, elongation, and dynamic recrystallization. The LPO indicates that slip occurred primarily on the (0kl)[100] slip system. This observation is consistent with the LPO observed by Bystricky et al. (2000) for samples of Fo90 that were also deformed in torsion. Bystricky, M., K. Kunze, L. Burlini, J.-P. Burg, Science, 290:1564-1567 (2000).

Zhao, Y.; Zimmerman, M. E.; Kohlstedt, D. L.

2006-12-01

111

Cold acclimation alters the connective tissue content of the zebrafish (Danio rerio) heart.  

PubMed

Thermal acclimation can alter cardiac function and morphology in a number of fish species, but little is known about the regulation of these changes. The purpose of the present study was to determine how cold acclimation affects zebrafish (Danio rerio) cardiac morphology, collagen composition and connective tissue regulation. Heart volume, the thickness of the compact myocardium, collagen content and collagen fiber composition were compared between control (27°C) and cold-acclimated (20°C) zebrafish using serially sectioned hearts stained with Picrosirius Red. Collagen content and fiber composition of the pericardial membrane were also examined. Cold acclimation did not affect the volume of the contracted heart; however, there was a significant decrease in the thickness of the compact myocardium. There was also a decrease in the collagen content of the compact myocardium and in the amount of thick collagen fibers throughout the heart. Cold-acclimated zebrafish also increased expression of the gene transcript for matrix metalloproteinase 2, matrix metalloproteinase 9, tissue inhibitor of metalloproteinase 2 and collagen Type I ?1. We propose that the reduction in the thickness of the compact myocardium as well as the change in collagen content may help to maintain the compliance of the ventricle as temperatures decrease. Together, these results clearly demonstrate that the zebrafish heart undergoes significant remodeling in response to cold acclimation. PMID:24577447

Johnson, Amy C; Turko, Andy J; Klaiman, Jordan M; Johnston, Elizabeth F; Gillis, Todd E

2014-06-01

112

Heme iron content in lamb meat is differentially altered upon boiling, grilling, or frying as assessed by four distinct analytical methods.  

PubMed

Lamb meat is regarded as an important source of highly bioavailable iron (heme iron) in the Iranians diet. The main objective of this study is to evaluate the effect of traditional cooking methods on the iron changes in lamb meat. Four published experimental methods for the determination of heme iron were assessed analytically and statistically. Samples were selected from lambs' loin. Standard methods (AOAC) were used for proximate analysis. For measuring heme iron, the results of four experimental methods were compared regarding their compliance to Ferrozine method which was used for the determination of nonheme iron. Among three cooking methods, the lowest total iron and heme iron were found in boiling method. The heme iron proportions to the total iron in raw, boiled lamb meat and grilled, were counted as 65.70%, 67.75%, and 76.01%, receptively. Measuring the heme iron, the comparison of the methods in use showed that the method in which heme extraction solution was composed of 90% acetone, 18% water, and 2% hydrochloric acid was more appropriate and more correlated with the heme iron content calculated by the difference between total iron and nonheme iron. PMID:23737716

Pourkhalili, Azin; Mirlohi, Maryam; Rahimi, Ebrahim

2013-01-01

113

Versatile and Biomass Synthesis of Iron-based Nanoparticles Supported on Carbon Matrix with High Iron Content and Tunable Reactivity  

SciTech Connect

Iron-based nanoparticles supported on carbon (FeNPs{at}C) have enormous potential for environmental applications. Reported is a biomass-based method for FeNP{at}C synthesis that involves pyrolysis of bleached wood fiber pre-mixed with Fe{sub 3}O{sub 4} nanoparticles. This method allows synthesis of iron-based nanoparticles with tunable chemical reactivity by changing the pyrolysis temperature. The FeNP{at}C synthesized at a pyrolysis temperature of 500 C (FeNP{at}C-500) reacts violently (pyrophoric) when exposed to air, while FeNP{at}C prepared at 800 C (FeNP{at}C-800) remains stable in ambient condition for at least 3 months. The FeNPs in FeNP{at}C-800 are mostly below 50 nm in diameter and are surrounded by carbon. The immediate carbon layer (within 5-15 nm radius) on the FeNPs is graphitized. Proof-of-concept environmental applications of FeNPs{at}C-800 were demonstrated by Rhodamine 6G and arsenate (V) removal from water. This biomass-based method provides an effective way for iron-based nanoparticle fabrication and biomass utilization.

Zhang, Dongmao [ORNL; Shi, Sheldon Q [ORNL; Jiang, Dongping [Mississippi State University (MSU); Che, Wen [Mississippi State University (MSU); Gai, Zheng [ORNL; Howe, Jane Y [ORNL; More, Karren Leslie [ORNL; Arockiasamy, Antonyraj [Mississippi State University (MSU)

2012-01-01

114

Effects of exposure to dietary chromium on tissue mineral contents in rats fed diets with fiber.  

PubMed

This study evaluated the effects of diets with fiber (cellulose and/or pectin) supplemented with chromium(III) on homeostasis of selected minerals in femurs, thigh muscles, livers, and kidneys of rats. For 6 weeks, male rats were fed experimental diets: a fiber-free diet (FF), a diet containing 5 % cellulose (CEL), 5 % pectin (PEC), or 2.5 % cellulose and 2.5 % pectin (CEL?+?PEC). These diets had 2.53 or 0.164 mg Cr/kg diet. The tissue levels of Ca, Mg, Zn, Fe, and Cr were determined by using atomic absorption spectrometry. Supplementing diets with Cr resulted in significantly higher Cr levels in the femurs of rats fed the CEL diet and significantly higher Cr and Fe levels in the rats fed the CEL?+?PEC diet compared to the rats fed FF diet. Muscle Ca content was significantly lower in the rats fed the CEL?+?PEC?+?Cr diet compared to the rats fed FF?+?Cr diet. The rats consuming the PEC?+?Cr diet had the highest liver Cr content. The highest kidney Zn content was observed in the rats fed diets containing Cr and one type of fiber. These results indicate that diets containing chromium at elevated dose and fiber have a significant effect on the mineral balance in rat tissues. PMID:24752971

Prescha, Anna; Krzysik, Monika; Zab?ocka-S?owi?ska, Katarzyna; Grajeta, Halina

2014-06-01

115

From tissue iron retention to low systemic haemoglobin levels, new pathophysiological biomarkers of human abdominal aortic aneurysm.  

PubMed

Iron deposits are observed in tissue of abdominal aortic aneurysm (AAA) patients, although the underlying mechanisms are not completely elucidated. Therefore we explored circulating markers of iron metabolism in AAA patients, and tested if they could serve as biomarkers of AAA. Increased red blood cell (RBC)-borne iron retention and transferrin, transferrin receptor and ferritin expression was observed in AAA tissue compared to control aorta (immunohistochemistry and western blot). In contrast, decreased circulating iron, transferrin, mean corpuscular haemoglobin concentration (MCHC) and haemoglobin concentration, along with circulating RBC count, were observed in AAA patients (aortic diameter >3 cm, n=114) compared to controls (aortic diameter <3 cm, n=88) (ELISA), whereas hepcidin concentrations were increased in AAA subjects (MS/MS assay). Moreover, iron, transferrin and haemoglobin levels were negatively, and hepcidin positively, correlated with aortic diameter in AAA patients. The association of low haemoglobin with AAA presence or aortic diameter was independent of specific risk factors. Moreover, MCHC negatively correlated with thrombus area in another cohort of AAA patients (aortic diameter 3-5 cm, n=357). We found that anaemia was significantly more prevalent in AAA patients (aortic diameter >5 cm, n=8,912) compared to those in patients with atherosclerotic aorto-iliac occlusive disease (n=17,737) [adjusted odds ratio=1.77 (95% confidence interval: 1.61;1.93)]. Finally, the mortality risk among AAA patients with anaemia was increased by almost 30% [adjusted hazard ratio: 1.29 (95% confidence interval: 1.16;1.44)] as compared to AAA subjects without anaemia. In conclusion, local iron retention and altered iron recycling associated to high hepcidin and low transferrin systemic concentrations could lead to reduced circulating haemoglobin levels in AAA patients. Low haemoglobin levels are independently associated to AAA presence and clinical outcome. PMID:24599423

Martinez-Pinna, R; Lindholt, J S; Madrigal-Matute, J; Blanco-Colio, L M; Esteban-Salan, M; Torres-Fonseca, M M; Lefebvre, T; Delbosc, S; Laustsen, J; Driss, F; Vega de Ceniga, M; Gouya, L; Weiss, G; Egido, J; Meilhac, O; Michel, J-B; Martin-Ventura, J

2014-07-01

116

Effects of additive iron on growth, tissue distribution, haematology and immunology of gilthead sea bream, Sparus aurata  

Microsoft Academic Search

The comparative effects of iron-supplemented levels on growth, tissue distribution, haematology and immunology of gilthead\\u000a sea bream, Sparus aurata (2 g) were investigated, using four organic (50, 100, 200, 300 mg ORG\\/kg diet) and one inorganic iron source (200 INOR mg\\/kg diet).\\u000a Fish were treated for 12 weeks with the experimental diets and maintained at a water temperature of 19–22°C. Growth (final\\u000a weight and specific growth

George RigosAlexandros; Alexandros Samartzis; Morgane Henry; Eleni Fountoulaki; Efthimia Cotou; John Sweetman; Simon Davies; Ioannis Nengas

2010-01-01

117

Effect of glucose content on thermally cross-linked fibrous gelatin scaffolds for tissue engineering.  

PubMed

Thermally cross-linked glucose-containing electrospun gelatin meshes were studied as possible cell substrate materials. FTIR analysis was used to study the effect of glucose on cross-linking reactions. It was found that the presence of glucose increases the extent of cross-linking of fibrous gelatin scaffolds, which in return determines scaffold properties and their usability in tissue engineering applications. Easy to handle fabric-like scaffolds were obtained from blends containing up to 15% glucose. Maximum extent of cross-linking was reached at nearly 20% glucose content. Cross-linking effectively resulted in decreased solubility and increased resistance to enzymatic degradation. Preliminary short-term cell culture experiments indicate that such thermally cross-linked gelatin-glucose scaffolds are suitable for tissue engineering applications. PMID:25063151

Siimon, Kaido; Reemann, Paula; Põder, Annika; Pook, Martin; Kangur, Triin; Kingo, Külli; Jaks, Viljar; Mäeorg, Uno; Järvekülg, Martin

2014-09-01

118

Distribution behavior of phosphorus in the coal-based reduction of high-phosphorus-content oolitic iron ore  

NASA Astrophysics Data System (ADS)

This study focuses on the reduction of phosphorus from high-phosphorus-content oolitic iron ore via coal-based reduction. The distribution behavior of phosphorus (i.e., the phosphorus content and the phosphorus distribution ratio in the metal, slag, and gas phases) during reduction was investigated in detail. Experimental results showed that the distribution behavior of phosphorus was strongly influenced by the reduction temperature, the reduction time, and the C/O molar ratio. A higher temperature and a longer reaction time were more favorable for phosphorus reduction and enrichment in the metal phase. An increase in the C/O ratio improved phosphorus reduction but also hindered the mass transfer of the reduced phosphorus when the C/O ratio exceeded 2.0. According to scanning electron microscopy analysis, the iron ore was transformed from an integral structure to metal and slag fractions during the reduction process. Apatite in the ore was reduced to P, and the reduced P was mainly enriched in the metal phase. These results suggest that the proposed method may enable utilization of high-phosphorus-content oolitic iron ore resources.

Sun, Yong-sheng; Han, Yue-xin; Gao, Peng; Ren, Duo-zhen

2014-04-01

119

Monoamines tissue content analysis reveals restricted and site-specific correlations in brain regions involved in cognition.  

PubMed

The dopamine (DA), noradrenalin (NA) and serotonin (5-HT) monoaminergic systems are deeply involved in cognitive processes via their influence on cortical and subcortical regions. The widespread distribution of these monoaminergic networks is one of the main difficulties in analyzing their functions and interactions. To address this complexity, we assessed whether inter-individual differences in monoamine tissue contents of various brain areas could provide information about their functional relationships. We used a sensitive biochemical approach to map endogenous monoamine tissue content in 20 rat brain areas involved in cognition, including 10 cortical areas and examined correlations within and between the monoaminergic systems. Whereas DA content and its respective metabolite largely varied across brain regions, the NA and 5-HT contents were relatively homogenous. As expected, the tissue content varied among individuals. Our analyses revealed a few specific relationships (10%) between the tissue content of each monoamine in paired brain regions and even between monoamines in paired brain regions. The tissue contents of NA, 5-HT and DA were inter-correlated with a high incidence when looking at a specific brain region. Most correlations found between cortical areas were positive while some cortico-subcortical relationships regarding the DA, NA and 5-HT tissue contents were negative, in particular for DA content. In conclusion, this work provides a useful database of the monoamine tissue content in numerous brain regions. It suggests that the regulation of these neuromodulatory systems is achieved mainly at the terminals, and that each of these systems contributes to the regulation of the other two. PMID:24120557

Fitoussi, A; Dellu-Hagedorn, F; De Deurwaerdère, P

2013-12-26

120

3-Dimensional quantitative detection of nanoparticle content in biological tissue samples after local cancer treatment  

NASA Astrophysics Data System (ADS)

X-ray computed tomography is nowadays used for a wide range of applications in medicine, science and technology. X-ray microcomputed tomography (XµCT) follows the same principles used for conventional medical CT scanners, but improves the spatial resolution to a few micrometers. We present an example of an application of X-ray microtomography, a study of 3-dimensional biodistribution, as along with the quantification of nanoparticle content in tumoral tissue after minimally invasive cancer therapy. One of these minimal invasive cancer treatments is magnetic drug targeting, where the magnetic nanoparticles are used as controllable drug carriers. The quantification is based on a calibration of the XµCT-equipment. The developed calibration procedure of the X-ray-µCT-equipment is based on a phantom system which allows the discrimination between the various gray values of the data set. These phantoms consist of a biological tissue substitute and magnetic nanoparticles. The phantoms have been studied with XµCT and have been examined magnetically. The obtained gray values and nanoparticle concentration lead to a calibration curve. This curve can be applied to tomographic data sets. Accordingly, this calibration enables a voxel-wise assignment of gray values in the digital tomographic data set to nanoparticle content. Thus, the calibration procedure enables a 3-dimensional study of nanoparticle distribution as well as concentration.

Rahn, Helene; Alexiou, Christoph; Trahms, Lutz; Odenbach, Stefan

2014-06-01

121

Thiamine and fatty acid content of walleye tissue from three southern U.S. reservoirs.  

PubMed

We determined the thiamine concentration in egg, muscle, and liver tissues of walleyes Sander vitreus and the fatty acid content of walleye eggs from three southern U.S. reservoirs. In two Tennessee reservoirs (Dale Hollow and Center Hill), in which there were alewives Alosa pseudoharengus in the forage base, natural recruitment of walleyes was not occurring; by contrast in Lake James Reservoir, North Carolina, where there were no alewives, the walleye population was sustained via natural recruitment. Female walleye tissues were collected and assayed for thiamine (vitamin B1) and fatty acid content. Thiamine pyrophosphate was found to be the predominant form of thiamine in walleye eggs. In 2000, mean total egg thiamine concentrations were similar among Center Hill, Dale Hollow, and Lake James reservoirs (2.13, 3.14, and 2.77 nmol thiamine/g, respectively). Egg thiamine concentration increased as maternal muscle (r2 = 0.73) and liver (r2 = 0.68) thiamine concentration increased. Walleye egg thiamine does not appear to be connected to poor natural reproduction in Tennessee walleyes. Threadfin shad Dorosoma petenense, which are found in all three reservoirs, had higher thiaminase activity than alewives. Six fatty acids differed among the walleye eggs for the three reservoirs. Two were physiologically important fatty acids, arachidonic acid (20:4[n-6]) and docosahexaenoic acid (22:6[n-3]), which are important eicosanoid precursors involved in the regulation of biological functions, such as immune response and reproduction. PMID:18201048

Honeyfield, Dale C; Vandergoot, Christopher S; Bettoli, Phillip W; Hinterkopf, Joy P; Zajicek, James L

2007-06-01

122

Evaluation of tissue doppler echocardiography and T2* magnetic resonance imaging in iron load of patients with thalassemia major.  

PubMed

Background: Iron-mediated cardiomyopathy is the main complication of thalassemia major (TM) patients. Therefore, there is an important clinical need in the early diagnosis and risk stratification of patients. The aim of this study was to evaluate the efficacy of tissue doppler imaging (TDI) to study cardiac iron overload in patients with TM using T2* magnetic resonance (MR) as the gold-standard non-invasive diagnostic test. Methods: A total of 100 TM patients with the mean age of 19±7 years and 100 healthy controls 18.8±7 years were evaluated. Conventional echocardiography, TDI, and cardiac MRI T2* were performed in all subjects. TDI measures included myocardial systolic (Sm), early (Em) and late (Am) diastolic velocities at basal and middle segments of septal and lateral LV wall. The TM patients were also subgrouped according to those with iron load (T2* ? 20 ms) and those without (T2* > 20 ms), and also severe (T2* ? 10 ms) versus the non-severe (T2* ? 10 ms). Results: Using T2* cardiovascular MR, abnormal myocardial iron load (T2* ? 20 ms) was detected in 84% of the patients and among these, 50% (42/84) had severe (T2* ? 10 ms) iron load. The mean T2* was 11.6±8.6 ms (5-36.7). A negative linear correlation existed between transfusion period of patients and T2* levels (r = -0.53, p=0.02). The following TDI measures were lower in patients than in controls: basal septal Am (p<0.05), mid-septal Em and Am (p<0.05), basal lateral Am (p<0.05), mid-lateral LV wall Sm (p<0.05) and Am (p<0.05). Conclusion: Tissue doppler imaging is helpful in predicting the presence of myocardial iron load in Thalassemia patients. Therefore, it can be used for screening of thalassemia major patients. PMID:24009962

Saravi, Mehrdad; Tamadoni, Ahmad; Jalalian, Rozita; Mahmoodi-Nesheli, Hassan; Hojati, Mosatafa; Ramezani, Saeed

2013-01-01

123

Hydration and tissue solid content of the lean body on prolonged exposure to altitude  

NASA Astrophysics Data System (ADS)

Using densitometric, hydrometric and anthropometric techniques, body fat, tissue solids, water and mineral content were quantitatively measured on two groups each of 26 young and healthy Indian soldiers of mixed ethnic composition. The experimental group was exposed to 3500 m altitude for 2 years and the experiments were carried out after 48 h and 3 weeks rehabilitation in Delhi (300 m). The control group was never exposed to high altidues. Inspite of the experimental group being fed with superior rations at high altitude, this group showed significantly hyperhydrated lean body with reduced tissue solids in comparison to the control group which was fed with identical rations in Delhi. The calculated mean density of the fat free body had declined to 0.092×103 kg/m3. The 3 week stay at low altitude had little influence on body composition. Hyperhydration, with reduced tissue solids, would cause reduction in the density of fat free body, and would thus interfere with the estimates of total body fat based on densitometric procedures alone. In the hyperhydrated state, Siri's formula overestimated fat by 22.8% of the true value.

Bharadwaj, H.; Singh, M. V.; Rawal, S. B.; Zachariah, T.; Kishnani, S.; Pramanik, S. N.; Gupta, A.; Rai, R. M.

1989-03-01

124

Carbon content in the Earth's inner core from the elasticity of iron carbide at high pressure  

NASA Astrophysics Data System (ADS)

Discrepancy between sound wave velocity of Fe-Ni alloys and seismological models indicate that Earth’s core is likely to contain lighter elements such as H, C, O, Si and S. Carbon is a plausible candidate because of its cosmic abundance and chemical affinity to iron at low pressures. Earlier it was thought that carbon, being volatile might have been lost during the accretionary stages of the planet. However, it is now known, that core formation likely took place from the deep magma ocean surrounded by solar-nebula type proto-atmosphere enriched in volatiles thus enabling incorporation of volatiles in to the molten core. Experimental studies conducted to study the phase diagram of Fe-C system revealed that volatility of carbon is only significant at pressures lower than 10-5 GPa. (Wood, 1993, EPSL, 117, 593) suggested that solid inner core might be composed of Fe3C. Recent experimental studies have extended the Fe-C phase diagram to considerably higher pressures (~70 GPa) and have found that Fe7C3 is the likely phase at the inner core conditions (Lord et al., 2009, EPSL, 284, 157). In this study we determine the elasticity of Fe7C3 using first principle methods. Results of compression for the ferromagnetic Fe7C3 is well represented by a third order Birch Murnaghan finite strain expression with K0~ 275 GPa, K?~2.5 and V0~ 182 Å3. Under compression magnetic moment gradually decreases and at ~69 GPa magnetic moment is instantaneously lost. Similar behavior has been reported for Fe3C at 60 GPa (Vocadlo et al., 2002, EPSL, 203, 567). The high-pressure non-magnetic phase has distinct elastic parameters with K0~ 228 GPa, K?~4.9 and V0~ 181 Å3. Calculated elastic constants also exhibit softening associated with the loss of magnetization. Similar anomalous behavior in thermoelastic parameter owing to loss of magnetization has been observed for Fe3C (Fiquet et al. 2009, PEPI, 172, 125) at 68 GPa. We will present full elastic tensor and sound wave velocity results for ferromagnetic and non-magnetic phase and infer about the carbon content of the inner core.

Steinle-Neumann, G.; Mookherjee, M.

2009-12-01

125

Coherent and incoherent scatterings for measurement of mandibular bone density and stable iodine content of tissue  

PubMed Central

The aim of present study is to investigate the feasibility of gamma ray scattering for measurements of mandibular bone density and stable iodine content of tissue. Scattered spectra from solutions of K2HPO4 in distilled water (a phantom simulating the mandibular bone) and KI in distilled water filled in a thin plastic vial (a phantom simulating the kinetics of thyroid iodine) are recorded for 59.54 and 145 keV incident gamma rays, respectively. A high-purity germanium detector is placed at various angular positions to record the scattered spectra originating from interactions of incident gamma rays with the phantom. The measured intensity ratio of coherent to incoherent scattered gamma rays, corrected for photo-peak efficiency of HPGe detector, absorption of gamma rays in air column present between phantom and detector, and self-absorption in the phantom, is found to be increasing linearly with increase in concentration of K2HPO4 and KI in distilled water within experimental estimated error of <6%. The regression lines, obtained from experimental data for intensity ratio, provide the bone density and stable iodine contents of thyroid. The present non-destructive technique has the potential for a measure of mandibular bone density and stable iodine contents of thyroid.

Sharma, Amandeep; Singh, Mohinderpal; Singh, Bhajan; Sandhu, Balvir S.

2009-01-01

126

Variations of tissue DNA density and nuclear DNA content in soybean lines and their impacts on the GMO quantification  

Microsoft Academic Search

The present study investigated the DNA density of the embryo, cotyledon, and seed coat of each soybean from 15 soybean cultivars, and evaluated the impacts of variations of tissue DNA density and nuclear DNA content in soybean lines on GMO quantification. The results have shown that DNA densities and DNA quantity ratios among the various tissues of soybean are significantly

Wen-Tao Xu; Kun-Lun Huang; Ai-Ke Deng; Zhi-hong Liang; Yun-Bo Luo

2007-01-01

127

HO-1-mediated macroautophagy: a mechanism for unregulated iron deposition in aging and degenerating neural tissues.  

PubMed

Oxidative stress, deposition of non-transferrin iron, and mitochondrial insufficiency occur in the brains of patients with Alzheimer disease (AD) and Parkinson disease (PD). We previously demonstrated that heme oxygenase-1 (HO-1) is up-regulated in AD and PD brain and promotes the accumulation of non-transferrin iron in astroglial mitochondria. Herein, dynamic secondary ion mass spectrometry (SIMS) and other techniques were employed to ascertain (i) the impact of HO-1 over-expression on astroglial mitochondrial morphology in vitro, (ii) the topography of aberrant iron sequestration in astrocytes over-expressing HO-1, and (iii) the role of iron regulatory proteins (IRP) in HO-1-mediated iron deposition. Astroglial hHO-1 over-expression induced cytoplasmic vacuolation, mitochondrial membrane damage, and macroautophagy. HO-1 promoted trapping of redox-active iron and sulfur within many cytopathological profiles without impacting ferroportin, transferrin receptor, ferritin, and IRP2 protein levels or IRP1 activity. Thus, HO-1 activity promotes mitochondrial macroautophagy and sequestration of redox-active iron in astroglia independently of classical iron mobilization pathways. Glial HO-1 may be a rational therapeutic target in AD, PD, and other human CNS conditions characterized by the unregulated deposition of brain iron. PMID:19250338

Zukor, Hillel; Song, Wei; Liberman, Adrienne; Mui, Jeannie; Vali, Hojatollah; Fillebeen, Carine; Pantopoulos, Kostas; Wu, Ting-Di; Guerquin-Kern, Jean-Luc; Schipper, Hyman M

2009-05-01

128

[Iron deficiency in domestic animals].  

PubMed

Iron is essential for the organism. In ionized forms (Fe++, Fe ), it constitutes an integrated part of a lot of different functional proteins (Figure 1). The most important functions are participation in oxygen transport in blood, oxygen storage in muscle tissues and oxidation of nutrients in the mitochondria. Iron is an essential part of cytochrome C and alpha-glycerolphosphate dehydrogenase, and early stages of iron deficiency may, therefore, cause disturbances in tissue metabolism before development of anaemia. Thus, haemoglobin determinations is not very suitable for diagnosing early iron deficiency. The content of iron in roughages, apart from root crops (Table II), is usually sufficient to cover the requirement of domestic animals (Table III), which is met by about 50 mg per kg feed dry matter. Iron deficiency is very often caused by a reduced absorption in the intestinal tract because of components in the feed forming complexes with iron of very low solubility or inhibitors reducing the absorption processes. The immune status of the organism and its resistance against infections depends on the iron supply. Iron deficiency inhibits the myeloperoxidase activity and thus decreases the bacteriocide effect of the leucocytes. In spite of this, when exposed to infections the physiological mechanisms reduce the blood concentration of available iron. By this mode of action, invading pathogens, needing iron like the host animals, will be restrained. The low content of iron in milk (Table II) combined with a high content of iron binding lactoferrin, is ideal to protect newborn and milk fed young animals against intestinal infections.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:6431395

Agergaard, N; Rotenberg, S; Boisen, S

1984-01-01

129

Do Secular Trends in the Nickel Content of Banded Iron Formation Record a Methanogen Famine?  

Microsoft Academic Search

As ancient chemical sediments whose composition was dictated by contemporaneous seawater, Banded Iron Formations (BIF) may prove to be one of the most useful indicators of changing oceanic trace element concentrations over geological timescales. We report here new trace element analyses of over 20 BIF spanning roughly 3 billion years of ocean history. Our data indicate a progressive decline in

S. V. Lalonde; E. Pecoits; D. Papineau; E. G. Nisbet; M. E. Barley; N. T. Arndt; K. Zahnle; B. S. Kamber; K. O. Konhauser

2008-01-01

130

Fluorescent characteristics and pharmacokinetic profiles of the fluorescent probe BCECF in various tissues: the role of blood content  

NASA Astrophysics Data System (ADS)

Microspectrofluorometry and fluorescence imaging have been largely used to measure the intracellular pH of living cells. Such in vivo measurements require the knowledge of the optical properties of the tissue and the pharmacokinetic of the dye. The purpose of this study was to investigate in vitro and in vivo spectral characteristics of BCECF. In vitro, measurements in presence of blood show that blood content can greatly affect pH measurement by increasing the fluorescence ratio. In vivo, the presence of blood in high vascularized tissue leads to the modification of BCECF spectral characteristics. Fluorescence kinetic profiles provides information about tissue perfusion. Consequently, pH measurements using BCECF or fluorescein derivatives by the double excitation method may be performed taking in account the tissue blood content and the tissue pharmacokinetic of the dye.

Devoisselle, Jean-Marie; Soulie-Begu, Sylvie; Mordon, Serge R.; Maillols, H.

1997-05-01

131

Content-based image retrieval applied to BI-RADS tissue classification in screening mammography  

PubMed Central

AIM: To present a content-based image retrieval (CBIR) system that supports the classification of breast tissue density and can be used in the processing chain to adapt parameters for lesion segmentation and classification. METHODS: Breast density is characterized by image texture using singular value decomposition (SVD) and histograms. Pattern similarity is computed by a support vector machine (SVM) to separate the four BI-RADS tissue categories. The crucial number of remaining singular values is varied (SVD), and linear, radial, and polynomial kernels are investigated (SVM). The system is supported by a large reference database for training and evaluation. Experiments are based on 5-fold cross validation. RESULTS: Adopted from DDSM, MIAS, LLNL, and RWTH datasets, the reference database is composed of over 10 000 various mammograms with unified and reliable ground truth. An average precision of 82.14% is obtained using 25 singular values (SVD), polynomial kernel and the one-against-one (SVM). CONCLUSION: Breast density characterization using SVD allied with SVM for image retrieval enable the development of a CBIR system that can effectively aid radiologists in their diagnosis.

de Oliveira, Julia Epischina Engracia; de Albuquerque Araujo, Arnaldo; Deserno, Thomas M

2011-01-01

132

The influence of combined magnesium and vanadate administration on the level of some elements in selected rat organs: V-Mg interactions and the role of iron-essential protein (DMT-1) in the mechanism underlying altered tissues iron level.  

PubMed

The effect of 12 week co-administration of sodium metavanadate (SMV) and magnesium sulfate (MS) on the levels of some elements in selected rats' organs and an attempt to elucidate a role of divalent metal transporter 1 (DMT-1) in the mechanism(s) of the SMV-induced disorders in some tissue Fe homeostasis were studied. SMV taken up separately or in combination with MS may pose a risk of the rise and shortage of the total hepatic and splenic Fe and Cu contents, respectively, cerebral Fe deficiency, splenic Ca deposition, and the hepatic, renal, and cerebral DMT-1 down-regulation. When administered alone, SMV may also cause the decrease in the total renal Fe and Cu contents. A visible protective effect of Mg against the renal and cerebral V accumulation and the decrease in the renal Fe and Cu contents during the SMV-MS co-administration together with our previous findings suggest a beneficial role of Mg at SMV exposure. Further, the SMV-induced fall in total iron binding capacity (TIBC), reported previously, and its correlations with the hepatic, splenic, and cerebral Fe levels allow us to suggest that diminished TIBC could be partly involved in the mechanism(s) responsible for the dramatic redistribution of Fe in those tissues. Finally, DMT-1, which potentially could participate in the hepatic non-transferrin Fe-bound uptake, does not play a significant role in this process indicating the need for studying other Fe transporters to more precisely elucidate molecular mechanism(s) underlying the hepatic Fe loading in our experimental conditions. PMID:24549458

Scibior, Agnieszka; Adamczyk, Agnieszka; Go??biowska, Dorota; Nied?wiecka, Irmina; Fornal, Emilia

2014-04-01

133

Estimation of total iron content in floodplain soils using VNIR spectroscopy – a case study in the Le'an River floodplain, China  

Microsoft Academic Search

Accumulation of heavy metals has become a serious environmental issue in China, especially in the floodplains downstream from mining and smelting sites. Estimation of total iron (Fe) content at the regional scale becomes particularly important because of the heavy metal sorption of Fe oxide. A novel method for estimating total Fe content is proposed using visible and near-infrared (VNIR) spectroscopy

Yaolin Liu; Yiyun Chen

2012-01-01

134

Modification of the ferrozine technique to analyze iron contents in different foods  

Microsoft Academic Search

A methodology for the determination of iron in foods fortified with this element or in nutritional products is important and\\u000a has to be sensitive and rapid. In developing countries, an inexpensive and reliable methodology is also required. For this\\u000a purpose, the Gordon’s Ferrozine technique was slightly modified and assayed with yogurt, dry powdered milk, and cereal mixtures,\\u000a all of them

A. E. Lysionek; M. B. Zubillaga; G. P. Calmanovici; M. J. Salgueiro; M. I. Sarabia; A. D. Barrado; R. A. Caro; Ricardo Weill; J. R. Boccio

1998-01-01

135

Influence of iron and copper consumption on weight gain and oxidative stress in adipose tissue of Wistar rats  

PubMed Central

The aim of the present study was to assess the effect of iron and copper consumption on weight gain and development of oxidative stress in adipose tissue of rats. Control rats obtained pure drinking water. Iron-treated groups of animals obtained FeSO4•12H2O with drinking water in concentrations of 3 and 6 mg/l, while copper-treated rats obtained CuSO4 in concentrations of 4.88 and 9.76 mg/l. The animals of the 6th group received a mixture of FeSO4•12H2O and CuSO4 in the respective concentrations of 3 and 4.88 mg/l in drinking water. All animals received a standard chow. The final weight of rats from all the experimental groups, especially in those obtaining the combination of iron and cooper, exceeded the control values. Maximal weight of fat pads was observed in animals receiving drinking water with 3 mg/l FeSO4•12H2O, 4.88 and 9.76 mg/l CuSO4, and the mixture of FeSO4•12H2O and CuSO4. The maximal intensity of free radical processes, as estimated by the concentration of fluorescent modified amino acids and the intensity of chemiluminescence in adipose tissue homogenates, was observed in rats obtaining iron in the concentration of 3 mg/l in the drinking water.

Ajsuvakova, Olga P.; Shehtman, Alexandr M.; Boev, Viktor M.; Nikonorov, Alexandr A.

2012-01-01

136

Quantification of Apoplastic Potassium Content by Elution Analysis of Leaf Lamina Tissue from Pea (Pisum sativum L. cv Argenteum) 1  

PubMed Central

K+ content and concentration within the apoplast of mesophyll tissue of pea (Pisum sativum L., cv Argenteum) leaflets were determined using an elution procedure. Following removal of the epidermis, a 1 centimeter (inside diameter) glass cylinder was attached to the exposed mesophyll tissue and filled with 5 millimolar CaCl2 solution (1°C). From time-course curves of cumulative K+ diffusion from the tissue, the amount of K+ of extracellular origin was estimated. Apoplastic K+ contents for leaves from plants cultured in nutrient solution containing 2 or 10 millimolar K+ were found to range from 1 to 4.5 micromoles per gram fresh weight, comprising less than 3% of the total K+ content within the lamina tissue. Assuming an apoplastic solution volume of 0.04 to 0.1 milliliters per gram fresh weight and a Donnan cation exchange capacity of 2.63 micromoles per gram fresh weight (experimentally determined), the K+ concentration within apoplastic solution was estimated at 2.4 to 11.8 millimolar. Net movement of Rb+ label from the extracellular compartment within mesophyll tissue into the symplast was demonstrated by pulse-chase experiments. It was concluded that the mesophyll apoplast in pea has a relatively low capacitance as an ion reservoir. Apoplastic K+ content was found to be highly sensitive to changes in xylem solution concentration. Images Figure 1

Long, Jean M.; Widders, Irvin E.

1990-01-01

137

Noble gas content and isotope abundances in phases of the Saint-Aubin (UNGR) iron meteorite  

NASA Astrophysics Data System (ADS)

We analyzed the noble gas isotopes in the Fe-Ni metal and inclusions of the Saint-Aubin iron meteorite, utilizing the stepwise heating technique to separate the various components of noble gases. The light noble gases in all samples are mostly cosmogenic, with some admixture from the terrestrial atmosphere. Total abundances of noble gases in metal are one of the lowest found so far in iron meteorites and the 4He/21Ne ratio is as high as 503, suggesting that the Saint-Aubin iron meteorite was derived from a very large meteoroid in space. The exposure ages obtained from cosmogenic 3He were 9-16 Ma. Saint-Aubin is very peculiar because it contains very large chromite crystals, which—like the metal—contain only cosmogenic and atmospheric noble gases. The noble gases in all the samples do not reveal any primordial components. The only exception is the 1000 °C fraction of schreibersite which contained about 5% of the Xe-HL component. The Xe-Q and the El Taco Xe components were not found and only the Xe-HL is present in this fraction. Some presolar diamond, the only carrier for the HL component known today, must have been available during growth of the schreibersite. However, it is also possible that this excess is due to the addition of cosmogenic and fission components. In this case, all the primordial components are masked (or lost) by the later events such as cosmic-ray irradiation, heating, and radioactive decay.

Nishimura, Chikako; Matsuda, Jun-Ichi; Kurat, Gero

2008-08-01

138

Effect of freeze–thaw cycles on total and heme iron contents of bonito ( Sarda sarda) and bluefish ( Pomatomus saltator) fillets  

Microsoft Academic Search

The effects of the number of freeze–thaw cycles on total and heme iron contents of bonito (Sarda sarda) and bluefish (Pomatomus saltator) fillets were investigated. The prepared fillets were packaged in polyethylene bags, the bags were heat sealed and than these samples were subjected to a total of 5 freeze–thaw cycles. Effects of freeze–thaw cycles on total and heme iron

Sadettin Turhan; N. Sule Ustun; Inci Bank

2006-01-01

139

Study on the Effect of Blood Content on Diffuse Reflectance Spectra of Basal Cell Carcinoma Skin Tissue  

PubMed Central

Diffuse reflectance spectrum as a noninvasive method has been widely used to study the optical properties of cutaneous skin tissue. In this work, we optimized an eight-layered optical model of basal cell carcinoma skin tissue to study its optical properties. Based on the model, the diffuse reflectance spectra were reconstructed in visible wavelength range by Monte Carlo methods. After different blood contents were added to the optical model, the contribution of blood to diffuese reflectance spectra was investigated theoretically. The ratios of basal cell carcinoma skin and normal skin tissue were also calculated for both experimental result and rebuilt results to testify the theoretical reasonability of the model and methods.

He, Qingli

2013-01-01

140

Measuring iron in the brain using quantitative susceptibility mapping and X-ray fluorescence imaging  

PubMed Central

Measuring iron content in the brain has important implications for a number of neurodegenerative diseases. Quantitative susceptibility mapping (QSM), derived from magnetic resonance images, has been used to measure total iron content in vivo and in post mortem brain. In this paper, we show how magnetic susceptibility from QSM correlates with total iron content measured by X-ray fluorescence (XRF) imaging and by inductively coupled plasma mass spectrometry (ICPMS). The relationship between susceptibility and ferritin iron was estimated at 1.10 ± 0.08 ppb susceptibility per ?g iron/g wet tissue, similar to that of iron in fixed (frozen/thawed) cadaveric brain and previously published data from unfixed brains. We conclude that magnetic susceptibility can provide a direct and reliable quantitative measurement of iron content and that it can be used clinically at least in regions with high iron content.

Zheng, Weili; Nichol, Helen; Liu, Saifeng; Cheng, Yu-Chung N.; Haacke, E. Mark

2013-01-01

141

Novel magnetic fibrin hydrogel scaffolds containing thrombin and growth factors conjugated iron oxide nanoparticles for tissue engineering  

PubMed Central

Novel tissue-engineered magnetic fibrin hydrogel scaffolds were prepared by the interaction of thrombin-conjugated iron oxide magnetic nanoparticles with fibrinogen. In addition, stabilization of basal fibroblast growth factor (bFGF) was achieved by the covalent and physical conjugation of the growth factor to the magnetic nanoparticles. Adult nasal olfactory mucosa (NOM) cells were seeded in the transparent fibrin scaffolds in the absence or presence of the free or conjugated bFGF-iron oxide nanoparticles. The conjugated bFGF enhanced significantly the growth and differentiation of the NOM cells in the fibrin scaffolds, compared to the same or even five times higher concentration of the free bFGF. In the presence of the bFGF-conjugated magnetic nanoparticles, the cultured NOM cells proliferated and formed a three-dimensional interconnected network composed mainly of tapered bipolar cells. The magnetic properties of these matrices are due to the integration of the thrombin- and bFGF-conjugated magnetic nanoparticles within the scaffolds. The magnetic properties of these scaffolds may be used in future work for various applications, such as magnetic resonance visualization of the scaffolds after implantation and reloading the scaffolds via magnetic forces with bioactive agents, eg, growth factors bound to the iron oxide magnetic nanoparticles.

Ziv-Polat, Ofra; Skaat, Hadas; Shahar, Abraham; Margel, Shlomo

2012-01-01

142

Mössbauer analysis of Nd-Co M-type strontium hexaferrite powders with different iron content  

Microsoft Academic Search

The structural analysis of strontium hexaferrites SrFe\\u000a x\\u000a O19 (for x?=?12, 11 and 10) and substituted samples Sr0.7Nd0.3Fe12???y\\u000a Co0.3O19 (for y?=?0.3,1.3 and 2.3) prepared through the citrate precursor method is shown. Nd and Co substitution modifies saturation magnetization\\u000a (M\\u000a \\u000a S\\u000a ) and increases coercivity (H\\u000a \\u000a c\\u000a ) in samples heat-treated at 1100°C for two hours. Mössbauer analyses show different iron

Carlos Herme; Silvia E. Jacobo; Paula G. Bercoff; Bibiana Arcondo

2010-01-01

143

Distributions of Manganese, Iron, and Manganese-Oxidizing Bacteria In Lake Superior Sediments of Different Organic Carbon Content  

NASA Technical Reports Server (NTRS)

Profiles of oxygen, soluble and particulate manganese and iron, organic carbon and nitrogen were examined in Lake Superior sediment cores, along with the distribution and abundance of heterotrophic and manganese oxidizing bacteria. Analyses were performed using cores collected with the submersible Johnson Sea Link II. Three cores, exhibiting a range of organic carbon content, were collected from the deepest basin in Lake Superior and the north and south ends of the Caribou trough, and brought to the surface for immediate analysis. Minielectrode profiles of oxygen concentration of the three cores were carried out using a commercially available minielectrode apparatus. Oxygen depletion to less than 1% occurred within 4 cm of the surface for two of the cores, but not until approximately 15 cm for the core from the south basin of the Caribou trough. The three cores exhibited very different profiles of soluble, as well as leachable, manganese and iron, suggesting different degrees of remobilization of these metals in the sediments. Vertical profiles of viable bacteria and Mn oxidizing bacteria, determined by plating and counting, showed that aerobic (and facultatively aerobic) heterotrophic bacteria were present at the highest concentrations near the surface and decreased steadily with depth, while Mn oxidizing bacteria were concentrations primarily at and above the oxic/anoxic interface. Soluble manganese in the pore waters, along with abundant organic carbon, appeared to enhance the presence of manganese oxidizing bacteria, even below the oxic/anoxic interface. Profiles of solid-phase leachable manganese suggested a microbial role in manganese reprecipitation in these sediments.

Richardson, Laurie L.; Nealson, Kenneth H.

1989-01-01

144

X-Ray Methods to Estimate Breast Density Content in Breast Tissue  

NASA Astrophysics Data System (ADS)

This work focuses on analyzing x-ray methods to estimate the fat and fibroglandular contents in breast biopsies and in breasts. The knowledge of fat in the biopsies could aid in their wide-angle x-ray scatter analyses. A higher mammographic density (fibrous content) in breasts is an indicator of higher cancer risk. Simulations for 5 mm thick breast biopsies composed of fibrous, cancer, and fat and for 4.2 cm thick breast fat/fibrous phantoms were done. Data from experimental studies using plastic biopsies were analyzed. The 5 mm diameter 5 mm thick plastic samples consisted of layers of polycarbonate (lexan), polymethyl methacrylate (PMMA-lucite) and polyethylene (polyet). In terms of the total linear attenuation coefficients, lexan ? fibrous, lucite ? cancer and polyet ? fat. The detectors were of two types, photon counting (CdTe) and energy integrating (CCD). For biopsies, three photon counting methods were performed to estimate the fat (polyet) using simulation and experimental data, respectively. The two basis function method that assumed the biopsies were composed of two materials, fat and a 50:50 mixture of fibrous (lexan) and cancer (lucite) appears to be the most promising method. Discrepancies were observed between the results obtained via simulation and experiment. Potential causes are the spectrum and the attenuation coefficient values used for simulations. An energy integrating method was compared to the two basis function method using experimental and simulation data. A slight advantage was observed for photon counting whereas both detectors gave similar results for the 4.2 cm thick breast phantom simulations. The percentage of fibrous within a 9 cm diameter circular phantom of fibrous/fat tissue was estimated via a fan beam geometry simulation. Both methods yielded good results. Computed tomography (CT) images of the circular phantom were obtained using both detector types. The radon transforms were estimated via four energy integrating techniques and one photon counting technique. Contrast, signal to noise ratio (SNR) and pixel values between different regions of interest were analyzed. The two basis function method and two of the energy integrating methods (calibration, beam hardening correction) gave the highest and more linear curves for contrast and SNR.

Maraghechi, Borna

145

Effect of iron content on the electrical conductivity of perovskite and magnesiowuestite assemblages at lower mantle conditions  

NASA Technical Reports Server (NTRS)

The electrical conductivity of (Mg/0.76/Fe/0.24/)SiO3 perovskite and of an assemblage of (Mg/0.89/Fe/0.11/)SiO3 perovskite + (Mg/0.70/Fe/0.30/)O magnesiowiestite was measured at pressures of 45-80 GPa and temperatures from 295 to 3600 K. The apparent activation energy for electrical conduction is 0.24 (+ or - 0.10) eV for the perovskite and 0.20 (+ or - 0.08) eV for the perovskite + magnesiowuestite assemblage. Comparing present results with those derived previously for Fe-poor samples, it is found that the electrical conductivities of both the silicate perovskite and the perovskite + magnesiowuestite assemblage depend strongly on iron content. Thus, the electrical conductivity distribution inside the earth could provide an important constraint in modeling the composition of the lower mantle.

Li, Xiaoyuan; Jeanloz, Raymond

1991-01-01

146

Iron content differs between Francisella tularensis subspecies tularensis and subspecies holarctica strains and correlates to their susceptibility to H(2)O(2)-induced killing.  

PubMed

Francisella tularensis, the causative agent of tularemia, is one of the most infectious bacterial pathogens known and is classified as a category A select agent and a facultative intracellular bacterium. Why F. tularensis subsp. tularensis causes a more severe form of tularemia than F. tularensis subsp. holarctica does is not known. In this study, we have identified prominent phenotypic differences between the subspecies, since we found that F. tularensis subsp. tularensis strains contained less iron than F. tularensis subsp. holarctica strains. Moreover, strain SCHU S4 of F. tularensis subsp. tularensis was less susceptible than FSC200 and the live vaccine strain (LVS) of F. tularensis subsp. holarctica to H(2)O(2)-induced killing. The activity of the H(2)O(2)-degrading enzyme catalase was similar between the strains, whereas the iron content affected their susceptibility to H(2)O(2), since iron starvation rendered F. tularensis subsp. holarctica strains more resistant to H(2)O(2). Complementing LVS with fupA, which encodes an important virulence factor that regulates iron uptake, reduced its iron content and increased the resistance to H(2)O(2)-mediated killing. By real-time PCR, it was demonstrated that FSC200 and LVS expressed higher levels of gene transcripts related to iron uptake and storage than SCHU S4 did, and this likely explained their high iron content. Together, the results suggest that F. tularensis subsp. tularensis strains have restricted iron uptake and storage, which is beneficial for their resistance to H(2)O(2)-induced killing. This may be an important factor for the higher virulence of this subspecies of F. tularensis, as reactive oxygen species, such as H(2)O(2), are important bactericidal components during tularemia. PMID:21189323

Lindgren, Helena; Honn, Marie; Salomonsson, Emelie; Kuoppa, Kerstin; Forsberg, Åke; Sjöstedt, Anders

2011-03-01

147

Changes of collagen, elastin, and tryptophan contents in laser welded porcine aorta tissues studied using fluorescence spectroscopy  

NASA Astrophysics Data System (ADS)

The emission spectra from welded and un-welded (normal) porcine aorta tissues were measured on both sides of intima and adventitia layers. A tunable Forsterite laser and a Cr4+: YAG laser with wavelengths of 1250nm, 1455nm and 1460nm were used to weld porcine aorta tissues. Three emission bands emitted from three key fluorophores were studied under different welding and excitation conditions. With excitation wavelength of 340nm, the 395nm band is associated with the emission from the structural proteins of collagen type III and type I. The 445nm band obtained is associated with the emission of the structural protein of elastin. The 350nm band recorded with excitation wavelength of 300nm is associated with the amino acid of tryptophan. The relative emission intensities of collagen, elastin and tryptophan at their fluorescence peaks changes with laser tissue welding wavelengths indicate the change of contents of those tissue molecules. The ratio of emission peak intensities of collagen to elastin with welding laser wavelength of 1250nm increases by 0.13 as compared to the normal aorta tissue at the intimal side. For the adventitial side of aorta tissue, this ratio decreases by 0.38 in comparison with the normal tissue. These results indicate that content of collagen changes relative to elastin due to laser tissue welding. The peak fluorescence intensity of tryptophan for both sides of welded tunica intima and adventitia increases significantly in comparison with the normal tissue when the optimum laser welding wavelength of 1455 nm was used.

Liu, C.-H.; Wang, W. B.; Kartazaev, V.; Savage, H.; Alfano, R. R.

2010-02-01

148

Manipulation of the n-3 polyunsaturated fatty acid content of muscle and adipose tissue in lambs.  

PubMed

Fifty Suffolk-crossbred wether lambs, with an initial live weight of 29 +/- 2.1 kg, were allocated to one of five concentrate-based diets formulated to have a similar fatty acid content (60 g/kg DM), but containing either linseed oil (high in 18:3n-3); fish oil (high in 20:5n-3 and 22:6n-3); protected linseed and soybean (PLS; high in 18:2n-6 and 18:3n-3); fish oil and marine algae (fish/algae; high in 20:5n-3 and 22:6n-3); or PLS and algae (PLS/algae; high in 18:3n-3 and 22:6n-3). Lambs were slaughtered when they reached 40 kg. Growth performance and intake were similar (P > 0.35) among treatments. By contrast, gain:feed was higher (P < 0.05) in lambs fed the fish oil compared with the linseed oil or PLS/algae diets. Total fatty acid concentration (mg/100 g) in the neutral lipid of the longissimus muscle was not affected by treatment (P > 0.87) but was least (P < 0.05) in the phospholipid fraction in lambs fed the linseed oil diet. Lambs fed either diet containing marine algae contained the highest (P < 0.05) percentage of 22:6n-3 in the phospholipid (mean of 5.2%), 2.8-fold higher than in sheep fed the fish oil diet. In lambs fed the fish/algae diet, the percentage of 20:5n-3 was highest (P < 0.05), contributing some 8.7, 0.8, and 0.5% of the total fatty acids in the muscle phospholipid, neutral lipids, and adipose tissue, respectively. The percentage of 18:3n-3 in the phospholipid fraction of the LM was highest (P < 0.05) in lambs fed the linseed oil diet (6.9%), a value double that of sheep fed the PLS diet. By contrast, lambs fed the PLS diet had twice the percentage of 18:3n-3 in the muscle neutral lipids (3.8%) than those offered the linseed oil diet, and 5.5-fold greater than lambs fed the fish/algae treatment (P < 0.05), an effect that was similar in the adipose tissue. The percentage of 18:2n-6 was highest (P < 0.05) in lambs fed the PLS diet, where it contributed 33.7, 10.1, and 11.2% in the muscle phospholipid, neutral lipids, and adipose tissue, respectively. The highest (P < 0.05) muscle PUFA-to-saturated fatty acid (P:S) ratio was obtained in lambs fed the PLS diet (0.57), followed by the PLS/algae diet (0.46), and those fed the fish oil or linseed oil diets had the lowest ratios (0.19 and 0.26, respectively). The favorable P:S ratio of lambs fed the PLS/algae diet, in conjunction with the increased levels of 20:5n-3 and 22:6n-3, enhanced the nutritional qualities of lamb to more closely resemble what is recommended for the human diet. PMID:15144087

Cooper, S L; Sinclair, L A; Wilkinson, R G; Hallett, K G; Enser, M; Wood, J D

2004-05-01

149

Cobalt and scandium partitioning versus iron content for crystalline phases in ultramafic nodules  

USGS Publications Warehouse

Fractionation of Co and Sc between garnets, olivines, and clino- and orthopyroxenes, separated from a suite of Salt Lake Crater ultramafic nodules that equilibrated at the same T and P, is strongly dependent on Fe contents. This observation suggests that petrogenetic equilibrium models of partial melting and crystal fractionation must take into account effects of magma composition, if they are to describe quantitatively geochemical evolutionary trends. ?? 1978.

Glassley, W. E.; Piper, D. Z.

1978-01-01

150

Method development and subsequent survey analysis of biological tissues for platinum, lead, and manganese content.  

PubMed Central

An emission spectrochemical method is described for the determination of trace quantities of platinum, lead, and manganese in biological tissues. Total energy burns in an argon-oxygen atmosphere are employed. Sample preparation, conditions of analysis, and preparation of standards are discussed. The precision of the method is consistently better than +/- 15%, and comparative analyses indicate comparable accuracies. Data obtained for experimental rat tissues and for selected autopsy tissues are presented.

Yoakum, A M; Stewart, P L; Sterrett, J E

1975-01-01

151

Hemochromatosis: Iron Storage Disease  

MedlinePLUS

... body's tissues and organs, a term called iron overload. If this iron buildup is untreated, it can, ... Detected? If your doctor suspects you have iron overload associated with hemochromatosis, there are two blood tests – ...

152

Particle induced x-ray emission (PIXE) measurement of the Cd content in animal tissues.  

National Technical Information Service (NTIS)

Particle induced x-ray emission (PIXE) measurements were performed on thin samples prepared from different rabbit tissues, using 3 MeV proton beam for inducing x-rays from the animal tissues. This method is very sensitive and very small amounts of trace e...

Le Huong Quynh I. Demeter K. Hollos-Nagy Z. Szoekefalvi-Nagy

1989-01-01

153

The effect of the reduction of carbon content on the toughness of high chromium white irons in the as-cast state  

Microsoft Academic Search

Three high chromium white cast irons were examined in the as-cast state to determine the effect of the carbon content on the fracture toughness. The plane strain fracture toughness KIc and the fracture strength were measured for each alloy. X-ray mapping was used to identify the phases on the fracture surfaces. Scanning electron fractography and optical microscopy were used to

A. Kootsookos; J. D. Gates

2004-01-01

154

Wall effects observed in tissue-equivalent proportional counters from 1.05 GeV/nucleon iron-56 particles  

NASA Technical Reports Server (NTRS)

Tissue-equivalent proportional counters (TEPCs) have been used to measure energy deposition in simulated volumes of tissue ranging in diameter from 0.1 to 10 microm. There has been some concern that the wall used to define the volume of interest could influence energy deposition within the sensitive volume because it has a density significantly greater than that of the cavity gas. These effects become important for high-velocity heavy ions. Measurements of energy deposition were made for 1 GeV/nucleon iron particles in a TEPC simulating a 1-microm-diameter sphere of tissue. The TEPC was nested within a particle spectrometer that provided identification and flight path of individual particles. Energy deposition was studied as a function of pathlength through the TEPC. Approximately 30% of the energy transfer along trajectories through the center of the detector escapes the sensitive volume. The response of the TEPC, for trajectories through the detector, is always larger than calculations for energy loss in a homogeneous medium. This enhancement is greatest for trajectories near the cavity/wall interface. An integration of the response indicates that charged-particle equilibrium is essentially achieved for a wall thickness of 2.54 mm. However, estimates of the linear energy transfer for the incident particles are influenced by these wall effects.

Rademacher, S. E.; Borak, T. B.; Zeitlin, C.; Heilbronn, L.; Miller, J.; Chatterjee, A. (Principal Investigator)

1998-01-01

155

Application of the wavelength dispersive X-ray fluorescence technique to determine soil fluorine with consideration of iron content in the matrix  

NASA Astrophysics Data System (ADS)

The suitability of the wavelength dispersive X-ray fluorescence (WD-XRF) technique for the quantitative analysis of fluorine in soil was assessed in this study. Fluorine standards for WD-XRF calibration with soil matrices consisting of SiO2, Al2O3, Fe2O3, and CaO were prepared by varying the concentrations of CaF2 as a source of fluorine. Based on the standard calibration, the limits of detection and quantification were calculated as 812 and 2690 mg-F/kg-solid (or 1.62 and 5.39 mg-F in absolute mass term), respectively. In addition, the fluorine intensities of the standard samples with high iron content increased significantly compared to those with low iron content. Because of proximity between F-K? and Fe-L? line, the higher iron content preferably helped increase background fluorine intensities. As a means to compensate for the iron interference effect in fluorine analysis, the correction factor (CF) (0.0045) was derived based on the slope ratios between the measured X-ray intensity at the Bragg angle of 43.174° and iron content in the standard sample. The soil fluorine concentration determined by WD-XRF after the CF adjustment exhibited a significantly high correlation with that of the classical alkali fusion-ISE analysis. These findings clearly demonstrated that the WD-XRF technique is reliable enough to allow an easy, precise, and rapid quantitative determination of fluorine in a solid sample (such as iron-bound soil) compared to conventional methods.

An, Jinsung; Kim, Ki-Hyun; Yoon, Hye-On; Seo, Jungju

156

The vitamin B12 content of human liver tissue obtained by aspiration biopsy  

PubMed Central

It is possible to estimate the vitamin B12 content of liver specimens obtained by needle biopsy. The liver B12 content is not related to the serum levels of vitamin B12, bilirubin, alkaline phosphatase, glutamic-oxaloacetic transaminase, or albumin. It is reduced in a number of pathological conditions of the liver and the reasons for this are discussed, as also are the factors determining the content of B12 in the normal liver.

Joske, R. A.

1963-01-01

157

Pork meat increases iron absorption from a 5-day fully controlled diet when compared to a vegetarian diet with similar vitamin C and phytic acid content.  

PubMed

Meat increases absorption of non-haem iron in single-meal studies. The aim of the present study was to investigate, over a 5 d period, the potential increasing effect of consumption of pork meat in a whole diet on the fractional absorption of non-haem iron and the total absorption of iron, when compared to a vegetarian diet. A randomised cross-over design with 3 x 5 d whole-diet periods with diets containing Danish-produced meat, Polish-produced meat or a vegetarian diet was conducted. Nineteen healthy female subjects completed the study. All main meals in the meat diets contained 60 g of pork meat and all diets had high phytic acid content (1250 mumol/d). All main meals were extrinsically labelled with the radioactive isotope (59)Fe and absorption of iron was measured in a whole body counter. The non-haem iron absorption from the Danish meat diet was significantly higher compared to the vegetarian diet (P=0.031). The mean fractional absorption of non-haem iron was 7.9 (se1.1), 6.8 (se 1.0) and 5.3 (se 0.6) % for the Danish and Polish meat diets and vegetarian diet, respectively. Total absorption of iron was higher for both meat diets compared to the vegetarian diet (Danish meat diet: P=0.006, Polish meat diet: P=0.003). The absorption ratios of the present study were well in accordance with absorption ratios estimated using algorithms on iron bioavailability. Neither the meat diets nor the vegetarian diets fulfilled the estimated daily requirements of absorbed iron in spite of a meat intake of 180 g/d in the meat diets. PMID:16115336

Bach Kristensen, Mette; Hels, Ole; Morberg, Catrine; Marving, Jens; Bügel, Susanne; Tetens, Inge

2005-07-01

158

In-Situ Characterization of Tissue Blood Flow, Blood Content, and Water State Using New Techniques in Magnetic Resonance Imaging.  

NASA Astrophysics Data System (ADS)

Tissue blood flow, blood content, and water state have been characterized in-situ with new nuclear magnetic resonance imaging techniques. The sensitivities of standard techniques to the physiologic tissue parameters spin density (N_{rm r}) and relaxation times (T_1 and T_2 ) are mathematically defined. A new driven inversion method is developed so that tissue T_1 and T_2 changes produce cooperative intensity changes, yielding high contrast, high signal to noise, and sensitivity to a wider range of tissue parameters. The actual tissue parameters were imaged by automated collection of multiple-echo data having multiple T _1 dependence. Data are simultaneously fit by three-parameters to a closed-form expression, producing lower inter-parameter correlation and parameter noise than in separate T_1 or T_2 methods or pre-averaged methods. Accurate parameters are obtained at different field strengths. Parametric images of pathology demonstrate high sensitivity to tissue heterogeneity, and water content is determined in many tissues. Erythrocytes were paramagnetically labeled to study blood content and relaxation mechanisms. Liver and spleen relaxation were enhanced following 10% exchange of animal blood volumes. Rapid water exchange between intracellular and extracellular compartments was validated. Erythrocytes occupied 12.5% of renal cortex volume, and blood content was uniform in the liver, spleen and kidney. The magnitude and direction of flow velocity was then imaged. To eliminate directional artifacts, a bipolar gradient technique sensitized to flow in different directions was developed. Phase angle was reconstructed instead of intensity since the former has a 2pi -fold higher dynamic range. Images of flow through curves demonstrated secondary flow with a centrifugally-biased laminar profile and stationary velocity peaks along the curvature. Portal vein flow velocities were diminished or reversed in cirrhosis. Image artifacts have been characterized and removed. The foldover in magnified images was eliminated by exciting limited regions with orthogonal pi/2 and pi pulses. Off-midline regions were imaged by tandemly offsetting the phase-encoding and excitation. Artifacts due to non-steady-state conditions were demonstrated. The approach to steady state was defined by operators and vectors, and any repeated series of RF pulses was proven to produce a steady-state. The vector difference between the magnetization and its steady state value is relatively constant during the approach. The repetition time relative to T_1 is the main determinant of approach rate, and off-resonant RF pulses incoherent with the magnetization produce a more rapid approach than on-resonant pulses.

Conturo, Thomas Edward

159

Cholesterol, Lipid Content, and Fatty Acid Composition of Different Tissues of Farmed Cobia ( Rachycentron canadum ) from China  

Microsoft Academic Search

Marine fishes are rich in n-3 polyunsaturated fatty acids (PUFA), especially eicosapentaenoic acid (EPA) and docosahexaenoic\\u000a acid (DHA), which are extremely important for human health. The objective of our work was to determine the content and composition\\u000a of lipids and fatty acids in the different tissues of cobia from China and to evaluate their nutritional value. The results\\u000a showed that

Shu Cheng Liu; De Tao Li; Peng Zhi Hong; Chao Hua Zhang; Hong Wu Ji; Jia Long Gao; Li Zhang

2009-01-01

160

Response of tissue phosphate content to acute dietary phosphate deprivation in the X-linked hypophosphatemic mouse  

Microsoft Academic Search

Summary  In order to evaluate a possible role for tissue phosphate or phosphorylated compounds in mediating the increase in plasma\\u000a 1,25(OH)2D3 levels during dietary phosphate deprivation, renal cortical phosphate content has been measured in both normal and X-linked\\u000a hypophosphatemic mice on a normal diet and also after acute dietary phosphate deprivation. We find that the metabolism of\\u000a inorganic phosphate and phosphorylated

Charles Eric Brown; Charles A. Wilkie; Martha H. Meyer; Ralph A. Meyer

1985-01-01

161

Iron metabolism and toxicity  

Microsoft Academic Search

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

G. Papanikolaou; K.. Pantopoulos

2005-01-01

162

Comparative transcriptome analysis of three oil palm fruit and seed tissues that differ in oil content and fatty acid composition.  

PubMed

Oil palm (Elaeis guineensis) produces two oils of major economic importance, commonly referred to as palm oil and palm kernel oil, extracted from the mesocarp and the endosperm, respectively. While lauric acid predominates in endosperm oil, the major fatty acids (FAs) of mesocarp oil are palmitic and oleic acids. The oil palm embryo also stores oil, which contains a significant proportion of linoleic acid. In addition, the three tissues display high variation for oil content at maturity. To gain insight into the mechanisms that govern such differences in oil content and FA composition, tissue transcriptome and lipid composition were compared during development. The contribution of the cytosolic and plastidial glycolytic routes differed markedly between the mesocarp and seed tissues, but transcriptional patterns of genes involved in the conversion of sucrose to pyruvate were not related to variations for oil content. Accumulation of lauric acid relied on the dramatic up-regulation of a specialized acyl-acyl carrier protein thioesterase paralog and the concerted recruitment of specific isoforms of triacylglycerol assembly enzymes. Three paralogs of the WRINKLED1 (WRI1) transcription factor were identified, of which EgWRI1-1 and EgWRI1-2 were massively transcribed during oil deposition in the mesocarp and the endosperm, respectively. None of the three WRI1 paralogs were detected in the embryo. The transcription level of FA synthesis genes correlated with the amount of WRI1 transcripts and oil content. Changes in triacylglycerol content and FA composition of Nicotiana benthamiana leaves infiltrated with various combinations of WRI1 and FatB paralogs from oil palm validated functions inferred from transcriptome analysis. PMID:23735505

Dussert, Stéphane; Guerin, Chloé; Andersson, Mariette; Joët, Thierry; Tranbarger, Timothy J; Pizot, Maxime; Sarah, Gautier; Omore, Alphonse; Durand-Gasselin, Tristan; Morcillo, Fabienne

2013-07-01

163

Monte Carlo simulation of light propagation in adult brain: influence of tissue blood content and indocyanine green  

NASA Astrophysics Data System (ADS)

Near-infrared spectroscopy (NIRS), applied to a human head, is a noninvasive method in neurointensive care to monitor cerebral hemodynamics and oxygenation. The method is particularly powerful when it is applied in combination with indocyanine green (ICG) as a tracer substance. In order to assess contributions to the measured optical density (OD) which are due to extracerebral circulation and disturb the clinically significant intracerebral signals, we simulated the light propagation in an anatomically representative model of the adult head derived from MRI measurements with the aid of Monte Carlo methods. Since the measured OD signal depends largely on the relative blood content in various transilluminated tissues, we weighted the calculated densities of the photon distribution under baseline conditions within the tissues with the changes and aberrations of the relative blood volumes which we expect to prevail under physiological conditions. Furthermore, the influence of the IGC dye as a tracer substance was assessed. We conclude that up to about different 70% of the measured OD signal may have its origin in the tissues of interest under optimal conditions, which is mainly due to the extrapolated high relative blood content of brain tissue along with the influence of ICG.

Niederer, P.; Mudra, R.; Keller, E.

2008-06-01

164

Absence of VLDL secretion does not affect alpha-tocopherol content in peripheral tissues.  

PubMed

alpha-Tocopherol is a lipid-soluble antioxidant that helps to prevent oxidative damage to cellular lipids. alpha-Tocopherol is absorbed by the intestine and is taken up and retained by the liver; it is widely presumed that alpha-tocopherol is then delivered to peripheral tissues by the secretion of VLDL. To determine whether VLDL secretion is truly important for the delivery of alpha-tocopherol to peripheral tissues, we examined alpha-tocopherol metabolism in mice that lack microsomal triglyceride transfer protein (Mttp) expression in the liver and therefore cannot secrete VLDL (Mttp(Delta/Delta) mice). Mttp(Delta/Delta) mice have low plasma lipid levels and increased stores of lipids in the liver. Similarly, alpha-tocopherol levels in the plasma were lower in Mttp(Delta/Delta) mice than in controls, whereas hepatic alpha-tocopherol stores were higher. However, alpha-tocopherol levels in the peripheral tissues of Mttp(Delta/Delta) mice were nearly identical to those of control mice, suggesting that VLDL secretion is not critical for the delivery of alpha-tocopherol to peripheral tissues. When fed a diet containing deuterated alpha-tocopherol, Mttp(Delta/Delta) and control mice had similar incorporation of deuterated alpha-tocopherol into plasma and various peripheral tissues. We conclude that the absence of VLDL secretion has little effect on the stores of alpha-tocopherol in peripheral tissues, at least in the mouse. PMID:16710047

Minehira-Castelli, Kaori; Leonard, Scott W; Walker, Quinn M; Traber, Maret G; Young, Stephen G

2006-08-01

165

Reduced Adipose Tissue Macrophage Content Is Associated With Improved Insulin Sensitivity in Thiazolidinedione-Treated Diabetic Humans  

PubMed Central

Obesity is associated with increased adipose tissue macrophage (ATM) infiltration, and rodent studies suggest that inflammatory factors produced by ATMs contribute to insulin resistance and type 2 diabetes. However, a relationship between ATM content and insulin resistance has not been clearly established in humans. Since thiazolidinediones attenuate adipose tissue inflammation and improve insulin sensitivity, we examined the temporal relationship of the effects of pioglitazone on these two parameters. The effect of 10 and 21 days of pioglitazone treatment on insulin sensitivity in 26 diabetic subjects was assessed by hyperinsulinemic-euglycemic clamp studies. Because chemoattractant factors, cytokines, and immune cells have been implicated in regulating the recruitment of ATMs, we studied their temporal relationship to changes in ATM content. Improved hepatic and peripheral insulin sensitivity was seen after 21 days of pioglitazone. We found early reductions in macrophage chemoattractant factors after only 10 days of pioglitazone, followed by a 69% reduction in ATM content at 21 days and reduced ATM activation at both time points. Although markers for dendritic cells and neutrophils were reduced at both time points, there were no significant changes in regulatory T cells. These results are consistent with an association between adipose macrophage content and systemic insulin resistance in humans.

Koppaka, Sudha; Kehlenbrink, Sylvia; Carey, Michelle; Li, Weijie; Sanchez, Elizabeth; Lee, Do-Eun; Lee, Hanna; Chen, Julie; Carrasco, Emilce; Kishore, Preeti; Zhang, Kehao; Hawkins, Meredith

2013-01-01

166

Chronic iron overload and toxicity: clinical chemistry perspective.  

PubMed

The content of body iron is regulated primarily by absorption since humans have no physiological mechanism by which excess iron is excreted. This regulation, however, is not absolute. Many factors such as the content of diets, iron doses, life styles, etc. influence iron absorption. In the past, nutrition programs for iron fortification and the ingestion of iron preparations have been widely practiced because of the seriousness of worldwide iron deficiency. Also, we now know that a significant number of asymptomatic people carry the hemochromatosis gene, HFE, indicating that these people have the potential to accumulate excess body iron in their lifetime. Excess body iron can be highly toxic. This toxicity involves many organs leading to a variety of serious diseases such as liver disease, heart disease, diabetes mellitus, hormonal abnormalities, dysfunctional immune system, etc. The tissue damage associated with iron overload is believed to result primarily from free radical reactions mediated by iron. Iron is an effective catalyst in free radical reactions. The diseases associated with iron overload can be managed effectively or prevented. Therefore, early diagnosis of iron overload and appropriate therapy are critical. By providing the necessary laboratory data, clinical chemistry laboratories can play the pivotal role in the management of these health problems. PMID:11517632

Kang, J O

2001-01-01

167

Quantitation of dopamine, serotonin and adenosine content in a tissue punch from a brain slice using capillary electrophoresis with fast-scan cyclic voltammetry detection  

PubMed Central

Methods to determine neurochemical concentrations in small samples of tissue are needed to map interactions among neurotransmitters. In particular, correlating physiological measurements of neurotransmitter release and the tissue content in a small region would be valuable. HPLC is the standard method for tissue content analysis but it requires microliter samples and the detector often varies by the class of compound being quantified; thus detecting molecules from different classes can be difficult. In this paper, we develop capillary electrophoresis with fast-scan cyclic voltammetry detection (CE-FSCV) for analysis of dopamine, serotonin, and adenosine content in tissue punches from rat brain slices. Using field-amplified sample stacking, the limit of detection was 5 nM for dopamine, 10 nM for serotonin, and 50 nM for adenosine. Neurotransmitters could be measured from a tissue punch as small as 7 µg (7 nL) of tissue, three orders of magnitude smaller than a typical HPLC sample. Tissue content analysis of punches in successive slices through the striatum revealed higher dopamine but lower adenosine content in the anterior striatum. Stimulated dopamine release was measured in a brain slice, then a tissue punch collected from the recording region. Dopamine content and release had a correlation coefficient of 0.71, which indicates much of the variance in stimulated release is due to variance in tissue content. CE-FSCV should facilitate measurements of tissue content in nanoliter samples, leading to a better understanding of how diseases or drugs affect dopamine, serotonin, and adenosine content.

Fang, Huaifang; Pajski, Megan L.; Ross, Ashley E.; Venton, B. Jill

2013-01-01

168

EFFECT OF SILICA AND VOLCANIC ASH ON THE CONTENT OF LUNG ALVEOLAR AND TISSUE PHOSPHOLIPIDS  

EPA Science Inventory

Silica or volcanic ash (VA) was administered to rats via intratracheal instillation and the changes in extracellular (i.e., lavage fluid) and tissue phospholipids, as well as various biochemical parameters, were monitored over a six month period. VA produced relatively minor (up ...

169

Postmortem tissue contents of {sup 241}Am in a person with a massive acute exposure  

SciTech Connect

{sup 241}Am was determined radiochemically in the tissues of USTUR Case 246, a 76-y-old man who died of cardiovascular disease 11 y after massive percutaneous exposure following a chemical explosion in a glove box. This worker was treated extensively with a chelation drug, DTPA, for over 4 y after exposure. The estimate {sup 241}Am deposition at the time of death was 540 kBq, of which 90% was in the skeleton, 5.1% in the liver, and 3.5% in muscle and fat. Among the soft tissues, the highest concentrations were observed in liver (22 Bq g{sup -1}), certain cartilaginous structures such as the larynx (15 Bq g{sup -1}) and the red marrow (9.7 Bq g{sup -1}), as compared with the mean soft tissue concentration of approximately 1 Bq g{sup -1}. Concentration in muscle was approximately that of the soft tissue average, while concentrations in the pancreas, a hilar lymph node and fat were less than the average. Concentrations in bone ash were inversely related to the ratio of ash weight to wet weight a surrogate for bone volume-to-surface ratio. the distribution of activity in this case is reasonable consistent with that observed in another human case, when allowance is made for chelation therapy, and also tends to support more recent models of {sup 241}Am metabolism. 26 refs., 2 figs., 4 tabs.

McInroy, J.F. [Los Alamos National Lab., NM (United States); Kathren, R.L. [Washington State Univ., Richland, WA (United States); Toohey, R.E. [Washington State Univ., Richland, WA (United States)]|[Oak Ridge Institute for Science and Education, TN (United States)] [and others

1995-09-01

170

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

PubMed

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. PMID:24511683

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

2013-01-01

171

Decreased content of integral membrane calcium-binding protein (IMCAL) in tissues of the spontaneously hypertensive rat.  

PubMed Central

Prior studies report that plasma membranes of the spontaneously hypertensive rat (Okamoto-Aoki strain) bind less calcium than do the corresponding preparations from Wistar Kyoto controls. The possibility that the differences result from a decrease in the content of integral membrane calcium-binding protein (IMCAL) was explored by the application of immunoassays with polyclonal antisera and a mouse monoclonal antibody. IMCAL binds calcium with relatively high affinity, and its content in many rat tissues is regulated by vitamin D and the level of dietary calcium. Immunoassays of tissue IMCAL demonstrate significant reductions in content in the erythrocyte ghost, intestinal mucosa, kidney, heart, testis, and liver of the spontaneously hypertensive rat as compared to the control strains. The decreases are observed both at 4-5 weeks of age, before the onset of severe hypertension and at 8-9 weeks in the presence of severe hypertension. Moreover, the magnitude of the decrease in erythrocyte IMCAL can account for much of the decrease in the calcium-binding capacity of erythrocyte membranes reported by others. The results are especially significant because an abnormality in the membrane binding of calcium and in the regulation of cytosolic calcium ion concentration could underlie the pathogenesis of the hypertension.

Kowarski, S; Cowen, L A; Schachter, D

1986-01-01

172

Photoinduced effect of hypericin on collagen and tissues with high collagen content  

NASA Astrophysics Data System (ADS)

The photoinduced effects of hypericin, a polycyclic quinone, on collagen has been investigated. It was found that after laser irradiation at both 532 nm and 337 nm, the spectral form of triple helix structure collagen fluorescence, changed to a spectral profile bearing resemblance to that of its polypeptide single chain counterpart, gelatin, or heated collagen. The effect of Chlorin e6 on collagen was also investigated and proved to be dissimilar to that of hypericin and not indicative of profound structural alterations. Second Harmonic Generation (SHG) of 1064 nm- nanosecond laser radiation in collagen was studied. While it was very efficient for pure collagen, the signal intensity was found to diminish by at least an order of magnitude after hypericin photosensitization or heating. The above noted fluorescence spectra form alteration was also observed in a smaller scale in collagen rich chicken tissue (tendon). Non sensitized chicken tendon tissue exhibited very efficient SHG, unlike skin and artery samples.

Yova, Dido M.; Theodossiou, Theodossis; Hovhannisyan, Vladimir A.

1999-01-01

173

Paretic Muscle Atrophy and Non-Contractile Tissue Content in Individual Muscles of the Post-Stroke Lower Extremity  

PubMed Central

Muscle atrophy is one of many factors contributing to post-stroke hemiparetic weakness. Since muscle force is a function of muscle size, the amount of muscle atrophy an individual muscle undergoes has implications for its overall force-generating capability post-stroke. In this study, post-stroke atrophy was determined bilaterally in fifteen leg muscles with volumes quantified using magnetic resonance imaging (MRI). All muscle volumes were adjusted to exclude non-contractile tissue content, and muscle atrophy was quantified by comparing the volumes between paretic and non-paretic sides. Non-contractile tissue or intramuscular fat was calculated by determining the amount of tissue excluded from the muscle volume measurement. With the exception of the gracilis, all individual paretic muscles examined had smaller volumes in the non-paretic side. The average decrease in volume for these paretic muscles was 23%. The gracilis volume, on the other hand, was approximately 11% larger on the paretic side. The amount of non-contractile tissue was higher in all paretic muscles except the gracilis, where no difference was observed between sides. To compensate for paretic plantar flexor weakness, one idea might be that use of the paretic gracilis actually causes the muscle to increase in size and not develop intramuscular fat. By eliminating non-contractile tissue from our volume calculations, we have presented volume data that more appropriately represents force-generating muscle tissue. Non-uniform muscle atrophy was observed across muscles and may provide important clues when assessing the effect of muscle atrophy on post-stroke gait.

Ramsay, John W.; Barrance, Peter J.; Buchanan, Thomas S.; Higginson, Jill S.

2011-01-01

174

ABCA1 in adipocytes regulates adipose tissue lipid content, glucose tolerance, and insulin sensitivity.  

PubMed

Adipose tissue contains one of the largest reservoirs of cholesterol in the body. Adipocyte dysfunction in obesity is associated with intracellular cholesterol accumulation, and alterations in cholesterol homeostasis have been shown to alter glucose metabolism in cultured adipocytes. ABCA1 plays a major role in cholesterol efflux, suggesting a role for ABCA1 in maintaining cholesterol homeostasis in the adipocyte. However, the impact of adipocyte ABCA1 on adipose tissue function and glucose metabolism is unknown. Our aim was to determine the impact of adipocyte ABCA1 on adipocyte lipid metabolism, body weight, and glucose metabolism in vivo. To address this, we used mice lacking ABCA1 specifically in adipocytes (ABCA1(-ad/-ad)). When fed a high-fat, high-cholesterol diet, ABCA1(-ad/-ad) mice showed increased cholesterol and triglyceride stores in adipose tissue, developed enlarged fat pads, and had increased body weight. Associated with these phenotypic changes, we observed significant changes in the expression of genes involved in cholesterol and glucose homeostasis, including ldlr, abcg1, glut-4, adiponectin, and leptin. ABCA1(-ad/-ad) mice also demonstrated impaired glucose tolerance, lower insulin sensitivity, and decreased insulin secretion. We conclude that ABCA1 in adipocytes influences adipocyte lipid metabolism, body weight, and whole-body glucose homeostasis. PMID:24443560

de Haan, Willeke; Bhattacharjee, Alpana; Ruddle, Piers; Kang, Martin H; Hayden, Michael R

2014-03-01

175

Sensing Lanthanide Metal Content in Biological Tissues with Magnetic Resonance Spectroscopy  

PubMed Central

The development and validation of MRI contrast agents consisting of a lanthanide chelate often requires a determination of the concentration of the agent in ex vivo tissue. We have developed a protocol that uses 70% nitric acid to completely digest tissue samples that contain Gd(III), Dy(III), Tm(III), Eu(III), or Yb(III) ions, or the MRI contrast agent gadodiamide. NMR spectroscopy of coaxial tubes containing a digested sample and a separate control solution of nitric acid was used to rapidly and easily measure the bulk magnetic susceptibility (BMS) shift caused by each lanthanide ion and gadodiamide. Each BMS shift was shown to be linearly correlated with the concentration of each lanthanide ion and gadodiamide in the 70% nitric acid solution and in digested rat kidney and liver tissues. These concentration measurements had outstanding precision, and also had good accuracy for concentrations ?10 mM for Tm(III) Eu(III), and Yb(III), and ?3 mM for Gd(III), gadodiamide, and Dy(III). Improved sample handling methods are needed to improve measurement accuracy for samples with lower concentrations.

Hingorani, Dina V.; Gonzalez, Sandra I.; Li, Jessica F.; Pagel, Mark D.

2013-01-01

176

Serum iron  

MedlinePLUS

Higher-than-normal levels may mean: Hemochromatosis Hemolysis Hemolytic anemias Hemosiderosis Liver tissue death (hepatic necrosis ) Hepatitis Vitamin B-12 deficiency, vitamin B-6 deficiency Iron poisoning Many blood transfusions Lower- ...

177

Correlated changes of some enzyme activities and cofactor and substrate contents of pea cotyledon tissue during germination  

PubMed Central

1. The activities of six enzymes (hexokinase, phosphoglucose isomerase, phosphofructokinase, aldolase, glucose 6-phosphate dehydrogenase and amylase) in extracts of pea cotyledons were determined. The activities during the first 10 days after germination showed individual and characteristic changes that indicate a specific control of both synthesis and destruction of enzymes. 2. Tissue contents of glucose, inorganic phosphate, glucose 6-phosphate, fructose 6-phosphate, ATP, ADP, AMP, NAD and NADP were also determined, and a correlation is reported between the substrate concentrations at day 1 and the subsequent enzymic activity. 3. The initial NAD+/NADH ratio value of 1 changed to about 3 by day 4; the NADP content was lower and changes in the oxidation state were less striking. The ratio of ATP to ADP and AMP remained virtually constant.

Brown, A. P.; Wray, J. L.

1968-01-01

178

Iron content of ferritin modulates its uptake by intestinal epithelium: implications for co-transport of prions  

PubMed Central

The spread of Chronic Wasting Disease (CWD) in the deer and elk population has caused serious public health concerns due to its potential to infect farm animals and humans. Like other prion disorders such a sporadic Creutzfeldt-Jakob-disease of humans and Mad Cow Disease of cattle, CWD is caused by PrP-scrapie (PrPSc), a ?-sheet rich isoform of a normal cell surface glycoprotein, the prion protein (PrPC). Since PrPSc is sufficient to cause infection and neurotoxicity if ingested by a susceptible host, it is important to understand the mechanism by which it crosses the stringent epithelial cell barrier of the small intestine. Possible mechanisms include co-transport with ferritin in ingested food and uptake by dendritic cells. Since ferritin is ubiquitously expressed and shares considerable homology among species, co-transport of PrPSc with ferritin can result in cross-species spread with deleterious consequences. We have used a combination of in vitro and in vivo models of intestinal epithelial cell barrier to understand the role of ferritin in mediating PrPSc uptake and transport. In this report, we demonstrate that PrPSc and ferritin from CWD affected deer and elk brains and scrapie from sheep resist degradation by digestive enzymes, and are transcytosed across a tight monolayer of human epithelial cells with significant efficiency. Likewise, ferritin from hamster brains is taken up by mouse intestinal epithelial cells in vivo, indicating that uptake of ferritin is not limited by species differences as described for prions. More importantly, the iron content of ferritin determines its efficiency of uptake and transport by Caco-2 cells and mouse models, providing insight into the mechanism(s) of ferritin and PrPSc uptake by intestinal epithelial cells.

2010-01-01

179

Ecotropic murine leukemia virus DNA content of normal and lymphomatous tissues of BXH-2 recombinant inbred mice.  

PubMed Central

BXH-2 recombinant inbred mice spontaneously produce a B-tropic murine leukemia virus (MuLV) beginning early in life and have a high incidence of non-T-cell lymphomas. These traits are not characteristic of the progenitor strains (C57BL/6J and C3H/HeJ) or of 11 other BXH recombinant inbred strains. Since B-tropic virus expression may be causally related to the high incidence of lymphoma in this strain, we have analyzed the ecotropic MuLV DNA content of both normal and lymphomatous tissues of BXH-2 mice. Southern analysis and hybridization with an ecotropic MuLV DNA-specific probe showed that DNA of normal BXH-2 tissues contained both parental N-tropic MuLV proviruses but lacked endogenous B-tropic MuLV DNA sequences. In addition, none of 116 F1 hybrid mice derived from male BXH-2 mice spontaneously produced ecotropic MuLV early in life. These results suggest that the B-tropic virus is horizontally transmitted in BXH-2 mice. Southern analysis of DNA from tumor tissues of 12 BXH-2 mice showed that amplification of ecotropic-specific DNA sequences had occurred in lymphomatous tissues of 3 mice and suggested that these tumors were monoclonal. The number of newly acquired proviruses, which appeared to be structurally nondefective and integrated at different sites, varied from one to three copies. Since lymphomatous tissues from only 3 of 12 mice examined carried additional detectable ecotropic proviruses, these results suggest that amplification of ecotropic MuLV DNA sequences is not required for maintenance of transformation in BXH-2 lymphomas. Images

Jenkins, N A; Copeland, N G; Taylor, B A; Bedigian, H G; Lee, B K

1982-01-01

180

Methodologies of tissue preservation and analysis of the glycogen content of the broiler chick liver.  

PubMed

The current study was performed to develop convenient, rapid, reliable, and pragmatic methodologies by which to harvest and preserve liver tissue glycogen and to analyze its levels within reasonable limits of quantification and with extended chromophore stability. Absorbance values decreased by 2 h and again by 24 h after preparation of the iodine-potassium iodide chromophore, whereas absorbance values of the phenol-sulfuric acid chromophore remained constant over the same time period. These absorbance trends for each chromophore followed full color development within 5 min after combining the analyte with the respective chromophore reagent. Use of the phenol-sulfuric acid reagent allowed for a 10-fold reduction in assay limits of detection and quantification when compared with the iodine-potassium iodide reagent. Furthermore, glycogen concentration-absorbance relationships were affected by the source (i.e., rabbit liver vs. bovine liver) of glycogen standards when the iodine-potassium iodide chromophore was used, but the source of the standards had no influence when the phenol-sulfuric acid chromophore was used. The indifference of the phenol-sulfuric acid method to the glycogen source, as exhibited by similar linear regressions of absorbance, may be attributed to actual determination of glucose subunit concentrations after complete glycogen hydrolysis by sulfuric acid. This is in contrast to the actual measurement of whole glycogen, which may exhibit source- or time-related molecular structural differences. The iodine-potassium iodide methodology is a test of whole glycogen concentrations; therefore, it may be influenced by glycogen structural differences. Liver tissue sample weight (between 0.16 and 0.36 g) and processing, which included mincing, immediate freezing, or refrigeration in 10% perchloric acid for 1 wk prior to tissue grinding, had no effect on glycogen concentrations that were analyzed by using the phenol-sulfuric acid reagent. These results indicate that small field samples may be minced, immediately placed in 10% perchloric acid without freezing, and then processed in the laboratory up to 1 wk later when using a phenol-sulfuric acid reagent, as described in this study, to determine the glycogen concentration in broiler chick livers accurately. PMID:18029813

Bennett, L W; Keirs, R W; Peebles, E D; Gerard, P D

2007-12-01

181

Relationships between silicon content and glutathione peroxidase activity in tissues of rats receiving lithium in drinking water.  

PubMed

Lithium salts are widely used in psychiatry, but their presence in organism can result in both beneficial and adverse effects. Silicon, the third most abundant trace element in humans as well as antioxidant enzyme glutathione peroxidase (GPx) play important roles in organism. The disturbance of their level can cause severe disorders. The aim of our work was to evaluate the influence of Li2CO3 administration in drinking water for a period of 4 weeks on Si content and GPx activity in the tissues of liver, kidney, brain and femoral muscle in rats. The concentrations of provided solutions were 0.7, 1.4, 2.6, 3.6, 7.1 and 10.7 mmol Li+ x dm-3. GPx activity was decreased versus control as a consequence of Li treatment, particularly in kidney and brain. This effect could be suggested to contribute to renal abnormalities which could occur during Li therapy. Si tissue level was significantly enhanced versus control in liver and femoral muscle in groups receiving high Li doses. In brain no well-marked changes were observed, whereas in kidney we observed the depletion in low-Li-groups, restoration of Si level in higher-Li-groups and unexpected decrease in the highest-Li-group. Positive correlations between Si content and GPx activity in the tissues of kidney (r = 0.677) and brain (r = 0.790) as well as negative correlation (r = -0.819) in femoral muscle were found. We consider that our results give some reason for suggesting that monitoring of silicon level in patients undergoing Li therapy could be recommended. However, more investigations should be performed, particularly regarding the relationships between Si and GPx in blood and urine Si excretion during lithium administration. PMID:17447120

Kie?czykowska, Ma?gorzata; Musik, Irena; Pasternak, Kazimierz

2008-02-01

182

The effect of iron-ore particles on the metal content of the brown alga Padina gymnospora (Espírito Santo Bay, Brazil).  

PubMed

The iron-ore particles discharged by a pellet processing plant (Espírito Santo Bay, Brazil) cover the seabed of Camburi Beach and consequently, the epibenthic community. In order to determine the importance of the contribution of the iron-ore deposits to the metal concentration in macroalgae of Espirito Santo Bay, four methods of cleaning particulate material adhered to the surface of thalli were tested prior to metal tissue analysis (Al, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn) of Padina gymnospora. In addition, heavy metal concentrations were determined in individuals of P. gymnospora from a site (Frade Island) not affected by the iron-ore particles. The most efficient cleaning treatment, a combination of scraping and washing with an ethanol-seawater solution (NA+SC+ET) removed a number of particles on the surface of thalli 10 times higher than that observed in the control (C). Using this treatment, the total-metal concentrations were reduced by 78% for Fe and 50% for Al respect to the control. However, Fe, Al and Cu concentrations after treatment NA+SC+ET were significantly higher than those found at Frade Island. It is suggested that the iron-ore deposit might be a source for metal availability to macroalgae exposed to the dumped material at Espirito Santo Bay. PMID:12628209

Nassar, Cristina A G; Salgado, Leonardo T; Yoneshigue-Valentin, Yocie; Amado Filho, Gilberto M

2003-01-01

183

The importance of carbon content beneath iron borides after boriding of chromium and nickel-based low-carbon steel  

Microsoft Academic Search

The complex (B+C) diffusion layers have been formed on chromium- and nickel-based low-carbon steels. Gas boriding applied to these steels that have been previously carburized enables the production of wear-resistant borocarburized layers. After combined surface hardening with boron and carbon in the microstructure two zones have been observed: iron borides (FeB+Fe2B) and carburized zones. The iron borides in borocarburized layer

M. Kulka; A. Pertek

2003-01-01

184

Comparative study of genotoxicity and tissue distribution of nano and micron sized iron oxide in rats after acute oral treatment  

SciTech Connect

Though nanomaterials (NMs) are being utilized worldwide, increasing use of NMs have raised concerns over their safety to human health and environment. Iron oxide (Fe{sub 2}O{sub 3}) NMs have important applications. The aim of this study was to assess the genotoxicity of Fe{sub 2}O{sub 3}-30 nm and Fe{sub 2}O{sub 3}-bulk in female Wistar rats. Fe{sub 2}O{sub 3}-30 nm was characterized by using transmission electron microscopy, dynamic light scattering, laser Doppler velocimetry and surface area analysis. The rats were treated orally with the single doses of 500, 1000, 2000 mg/kg bw of Fe{sub 2}O{sub 3}-30 nm and Fe{sub 2}O{sub 3} –bulk. The genotoxicity was evaluated at 6, 24, 48 and 72 h by the comet assay in leucocytes, 48 and 72 h by micronucleus test (MNT) in peripheral blood cells, 18 and 24 h by chromosomal aberration (CA) assay and 24 and 48 h by MNT in bone marrow cells. The biodistribution of iron (Fe) was carried out at 6, 24, 48 and 72 h after treatment in liver, spleen, kidney, heart, brain, bone marrow, urine and feces by using atomic absorption spectrophotometry. The % tail DNA, frequencies of micronuclei and CAs were statistically insignificant (p > 0.05) at all doses. These results suggest that Fe{sub 2}O{sub 3}-30 nm and Fe{sub 2}O{sub 3}-bulk was not genotoxic at the doses tested. Bioavailability of Fe was size and dose dependent in all the tissues from the groups exposed to Fe{sub 2}O{sub 3}-30 nm. Fe{sub 2}O{sub 3} NMs were able to enter in the organs and the rats are biocompatible with much higher concentration of Fe. However, the accumulated Fe did not cause significant genotoxicity. This study provides additional knowledge about the toxicology of Fe{sub 2}O{sub 3} NMs. -- Highlights: ? Fe{sub 2}O{sub 3}-30 nm and Fe{sub 2}O{sub 3}-bulk were orally administered to rats with single doses. ? The nano and bulk Fe{sub 2}O{sub 3} showed insignificant results with MNT, comet and CA assays. ? The bulk was excreted via feces whereas the NMs were found both in urine and feces. ? The NMs mainly accumulated in the liver, spleen, kidney, heart and bone marrow. ? However the accumulated Fe did not cause significant genotoxicological effects.

Singh, Shailendra Pratap; Rahman, M.F.; Murty, U.S.N.; Mahboob, M.; Grover, Paramjit, E-mail: paramgrover@gmail.com

2013-01-01

185

Applied potential tomography shows differential changes in fluid content of leg tissue layers in microgravity.  

PubMed

Absence of hydrostatic forces in the human cardiocirculatory system normally leads to an overall body fluid deficit. It was hypothesized that this is mainly due to a loss of interstitial fluid. An experiment was performed on board the Russian MIR station. Cuffs were positioned around both thighs and inflated up to suprasystolic values. This maneuver took place just before and after immediately a lower body negative pressure session (LBNP). The redistribution of fluids underneath the cuffs was assessed by means of cross-sectional impedance tomography (Applied Potential Tomography, APT). A microgravity induced loss of interstitial fluid was measured in all layers of the observed cross-section. The APT-readings changed significantly (SD approximately +/- .9) from 3.0 at 1g to 1.7 at 0g for the outer layer and from 2.7 at 1g to 2.0 at 0g for the middle layer (expressed in arbitrary units). The LBNP maneuver was able to fill the interstitial space but only at levels higher than -15 mmHg LBNP. This suggests that the superficial tissues in the legs are as much affected as the deeper ones by changing g-conditions and LBNP can be used to counteract interstitial fluid loss in this area. PMID:11537940

Baisch, F J

1994-01-01

186

Constitutive Expression of Soybean Ferritin cDNA Intransgenic Wheat and Rice Results in Increased Iron Levels in Vegetative Tissues but not in Seeds  

Microsoft Academic Search

We used particle bombardment to produce transgenic wheat and rice plants expressing recombinant soybean ferritin, a protein that can store large amounts of iron. The cDNA sequence was isolated from soybean by RT-PCR and expressed using the constitutive maize ubiquitin-1 promoter. The presence of ferritin mRNA and protein was confirmed in the vegetative tissues and seeds of transgenic wheat and

Georgia Drakakaki; Paul Christou; Eva Stöger

2000-01-01

187

Ethnomedical study and iron content of some medicinal herbs used in traditional medicine in Cote d'Ivoire for the treatment of anaemia.  

PubMed

Medicinal plants have been a source of succour in the control of many diseases in developing countries and anaemia is no exception. In this study, ethnomedical survey was carried out for recording medicinal plants used in Northern and South-Eastern Côte d'Ivoire against anaemia. Also iron content was determined for some of the recorded plants using phenanthroline method. Thirty (30) medicinal plants, covering 28 genera and 22 families were recorded. These plants were used to prepare 30 receipts for the treatment of anaemia and aggravating factors such as malaria and gastro-intestinal helminthes. Eleven (11) of these medicinal plants showed presence of iron in various quantities. The most promising were Tectona grandis, Amaranthus spinosus and Stylosanthes erecta which contained the highest iron contents viz; 266.6, 236.6 and 206.6 mg/100 g respectively. They were followed by Hoslundia opposita, Imperata cylindrica, Cajanus cajan, Thalia geniculata and Milicia excelsa. These results lend credence to the traditional use of these plants in Cote d'Ivoire's ethnomedicine for the treatment of anaemia. PMID:23983324

Koné, W Mamidou; Koffi, A G; Bomisso, E L; Tra Bi, F H

2012-01-01

188

[Micromethod for the fluorometric determination of the polyamine and putrescine content in animal tissues by thin-layer chromatography on Silufol UV-254 plates].  

PubMed

A microquantitative, simple, rapid, highly sensitive procedure is described for estimation of polyamines and putrescine in animal tissues. Content of these substances was studied in several rapidly proliferating tissues. Statistically distinct increase in content of putrescine and polyamines was found in regenerating, malignant rat liver tissue and in hepatomas G-27 and G-46. The mean error of the assay was about 3%, its sensitivity was +/- 0.1 nmol per 1 mg of protein, reproducibility was close to 95-100%. PMID:7336662

Siatkin, S P; Berezov, T T

1981-01-01

189

Effects of Different Dietary Cadmium Levels on Growth and Tissue Cadmium Content in Juvenile Parrotfish, Oplegnathus fasciatus  

PubMed Central

This feeding trial was carried out to evaluate the effects of different dietary cadmium levels on growth and tissue cadmium content in juvenile parrotfish, Oplegnathus fasciatus, using cadmium chloride (CdCl2) as the cadmium source. Fifteen fish averaging 5.5±0.06 g (mean±SD) were randomly distributed into each of twenty one rectangular fiber tanks of 30 L capacity. Each tank was then randomly assigned to one of three replicates of seven diets containing 0.30 (C0), 21.0 (C21), 40.7 (C41), 83.5 (C83), 162 (C162), 1,387 (C1,387) and 2,743 (C2,743) mg cadmium/kg diet. At the end of sixteen weeks of feeding trial, weight gain (WG), specific growth rate (SGR) and feed efficiency (FE) of fish fed C21 were significantly higher than those of fish fed C83, C162, C1,387 and C2,743 (p<0.05). Weight gain, SGR and FE of fish fed C0, C21 and C41 were significantly higher than those of fish fed C162, C1,387 and C2,743. Protein efficiency ratio of fish fed C0, C21 and C41 were significantly higher than those of fish fed C1,387 and C2,743. Average survival of fish fed C0, C21, C41 and C162 were significantly higher than that of fish fed C2,743. Tissue cadmium concentrations increased with cadmium content of diets. Cadmium accumulated the most in liver, followed by gill and then muscle. Muscle, gill and liver cadmium concentrations of fish fed C0, C21, C41 and C83 were significantly lower than those of fish fed C162, C1,387 and C2,743. Based on the ANOVA results of growth performance and tissue cadmium concentrations the safe dietary cadmium level could be lower than 40.7 mg Cd/kg diet while the toxic level could be higher than 162 mg Cd/kg diet.

Okorie, Okorie E.; Bae, Jun Young; Lee, Jun-Ho; Lee, Seunghyung; Park, Gun-Hyun; Mohseni, Mahmoud; Bai, Sungchul C.

2014-01-01

190

Effects of selenium on liver and muscle contents and urinary excretion of zinc, copper, iron and manganese.  

PubMed

Selenium is a main component of glutathione peroxidase (GPX), a key antioxidant enzyme. Other elements, such as zinc, copper, manganese and iron, are also involved in the pathogenesis of oxidative damage as well as in other important metabolic pathways. The effects of selenium supplementation on the metabolism of these elements have yield controversial results .The aim of this study is to analyse the effects of selenium supplementation on liver, muscle and urinary excretion of zinc, copper, iron and manganese in a situation of oxidative stress, such as protein deficiency. The experimental design included four groups of adult male Sprague-Dawley rats, which received the Lieber-DeCarli control diet, an isocaloric 2 % protein-containing diet and another similar two groups to which selenomethionine (6 mg/l liquid diet) was added. After sacrifice (5 weeks later), muscle, liver and serum selenium were determined, as well as muscle, liver and urinary zinc, copper, manganese and iron and liver GPX activity and liver malondialdehyde. Selenium addition led to decreased liver copper, increased muscle copper, increased copper excretion and increased liver iron, whereas zinc and manganese parameters were essentially unaltered. Muscle, liver and serum selenium were all significantly correlated with liver GPX activity. PMID:24622908

Monedero-Prieto, María José; González-Pérez, José María; González-Reimers, Emilio; Hernández-Pérez, Onán; Monereo-Muñoz, María; Galindo-Martín, Luis; Quintero-Platt, Geraldine; Abreu-González, Pedro

2014-05-01

191

Friction and wear with a single-crystal abrasive grit of silicon carbide in contact with iron base binary alloys in oil: Effects of alloying element and its content  

NASA Technical Reports Server (NTRS)

Sliding friction experiments were conducted with various iron-base binary alloys (alloying elements were Ti, Cr, Mn, Ni, Rh, and W) in contact with a rider of 0.025-millimeter-radius, single-crystal silicon carbide in mineral oil. Results indicate that atomic size and content of alloying element play a dominant role in controlling the abrasive-wear and -friction properties of iron-base binary alloys. The coefficient of friction and groove height (wear volume) general alloy decrease, and the contact pressure increases in solute content. There appears to be very good correlation of the solute to iron atomic radius ratio with the decreasing rate of coefficient of friction, the decreasing rate of groove height (wear volume), and the increasing rate of contact pressure with increasing solute content C. Those rates increase as the solute to iron atomic radius ratio increases from unity.

Miyoshi, K.; Buckley, D. H.

1979-01-01

192

Distribution and quantitation of skin iron in primary haemochromatosis: correlation with total body iron stores in patients undergoing phlebotomy.  

PubMed

Measurement of the concentration of iron in the skin, if correlated with total body iron stores, may enable better informed decisions on when to initiate, change or stop therapy in hereditary heamochromatosis. Naïve haemochromatosis patients with iron overload and with C282Y and/or H63D HFE mutations were evaluated at the following time-points: disease diagnosis, end of the therapy programme, and 6 months after the end of therapy. The distribution and concentration of iron in the skin were assessed by quantitative nuclear microscopy methods, in parallel with serum and plasma iron concentration. Iron content in the liver was determined by nuclear magnetic resonance. Iron accumulated in the epidermis; its concentration increased from outer to inner layers, being maximal in the basal layer (7.33?±?0.98 µmol/g). At all 3 time-points, most of the iron was associated with the extracellular space. During the phlebotomy programme the iron content of the skin and the liver decreased by a factor of 2. These data suggest that measurements of iron concentration in the epidermis, which is a readily accessible tissue, reflect iron overload in the liver. PMID:23728724

Pinheiro, Teresa; Silva, Raquel; Fleming, Rita; Gonçalves, Afonso; Barreiros, Maria A; Silva, João N; Morlière, Patrice; Santus, René; Filipe, Paulo

2014-01-01

193

Nicotianamine synthase overexpression positively modulates iron homeostasis-related genes in high iron rice.  

PubMed

Nearly one-third of the world population, mostly women and children, suffer from iron malnutrition and its consequences, such as anemia or impaired mental development. Biofortification of rice, which is a staple crop for nearly half of the world's population, can significantly contribute in alleviating iron deficiency. NFP rice (transgenic rice expressing nicotianamine synthase, ferritin and phytase genes) has a more than six-fold increase in iron content in polished rice grains, resulting from the synergistic action of nicotianamine synthase (NAS) and ferritin transgenes. We investigated iron homeostasis in NFP plants by analyzing the expression of 28 endogenous rice genes known to be involved in the homeostasis of iron and other metals, in iron-deficient and iron-sufficient conditions. RNA was collected from different tissues (roots, flag leaves, grains) and at three developmental stages during grain filling. NFP plants showed increased sensitivity to iron-deficiency conditions and changes in the expression of endogenous genes involved in nicotianamine (NA) metabolism, in comparison to their non-transgenic siblings (NTS). Elevated transcript levels were detected in NFP plants for several iron transporters. In contrast, expression of OsYSL2, which encodes a member of yellow stripe like protein family, and a transporter of the NA-Fe(II) complex was reduced in NFP plants under low iron conditions, indicating that expression of OsYSL2 is regulated by the endogenous iron status. Expression of the transgenes did not significantly affect overall iron homeostasis in NFP plants, which establishes the engineered push-pull mechanism as a suitable strategy to increase rice endosperm iron content. PMID:23755054

Wang, Meng; Gruissem, Wilhelm; Bhullar, Navreet K

2013-01-01

194

Nicotianamine synthase overexpression positively modulates iron homeostasis-related genes in high iron rice  

PubMed Central

Nearly one-third of the world population, mostly women and children, suffer from iron malnutrition and its consequences, such as anemia or impaired mental development. Biofortification of rice, which is a staple crop for nearly half of the world's population, can significantly contribute in alleviating iron deficiency. NFP rice (transgenic rice expressing nicotianamine synthase, ferritin and phytase genes) has a more than six-fold increase in iron content in polished rice grains, resulting from the synergistic action of nicotianamine synthase (NAS) and ferritin transgenes. We investigated iron homeostasis in NFP plants by analyzing the expression of 28 endogenous rice genes known to be involved in the homeostasis of iron and other metals, in iron-deficient and iron-sufficient conditions. RNA was collected from different tissues (roots, flag leaves, grains) and at three developmental stages during grain filling. NFP plants showed increased sensitivity to iron-deficiency conditions and changes in the expression of endogenous genes involved in nicotianamine (NA) metabolism, in comparison to their non-transgenic siblings (NTS). Elevated transcript levels were detected in NFP plants for several iron transporters. In contrast, expression of OsYSL2, which encodes a member of yellow stripe like protein family, and a transporter of the NA-Fe(II) complex was reduced in NFP plants under low iron conditions, indicating that expression of OsYSL2 is regulated by the endogenous iron status. Expression of the transgenes did not significantly affect overall iron homeostasis in NFP plants, which establishes the engineered push-pull mechanism as a suitable strategy to increase rice endosperm iron content.

Wang, Meng; Gruissem, Wilhelm; Bhullar, Navreet K.

2013-01-01

195

Iron-dependent modifications of the flower transcriptome, proteome, metabolome, and hormonal content in an Arabidopsis ferritin mutant  

PubMed Central

Iron homeostasis is an important process for flower development and plant fertility. The role of plastids in these processes has been shown to be essential. To document the relationships between plastid iron homeostasis and flower biology further, a global study (transcriptome, proteome, metabolome, and hormone analysis) was performed of Arabidopsis flowers from wild-type and triple atfer1-3-4 ferritin mutant plants grown under iron-sufficient or excess conditions. Some major modifications in specific functional categories were consistently observed at these three omic levels, although no significant overlaps of specific transcripts and proteins were detected. These modifications concerned redox reactions and oxidative stress, as well as amino acid and protein catabolism, this latter point being exemplified by an almost 10-fold increase in urea concentration of atfer1-3-4 flowers from plants grown under iron excess conditions. The mutant background caused alterations in Fe–haem redox proteins located in membranes and in hormone-responsive proteins. Specific effects of excess Fe in the mutant included further changes in these categories, supporting the idea that the mutant is facing a more intense Fe/redox stress than the wild type. The mutation and/or excess Fe had a strong impact at the membrane level, as denoted by the changes in the transporter and lipid metabolism categories. In spite of the large number of genes and proteins responsive to hormones found to be regulated in this study, changes in the hormonal balance were restricted to cytokinins, especially in the mutant plants grown under Fe excess conditions.

Sudre, Damien; Gutierrez-Carbonell, Elain; Rellan-Alvarez, Ruben; Briat, Jean-Francois

2013-01-01

196

The wear behaviour of high-chromium white cast irons as a function of silicon and Mischmetal content  

Microsoft Academic Search

The sliding wear behaviour of high-chromium white cast iron (16.8% Cr) has been examined as a function of silicon and Mischmetal alloy additions (1, 2, 3 and 5% Si and 0.1 and 0.3% Mischmetal). Such additions are known to modify the structure, but there is considerable controversy as to the exact effect. Silicon was found to refine the dendritic structure

A. Bedolla Jacuinde; W. M. Rainforth

2001-01-01

197

Comparison of Transferrin Receptors, Iron Content and Isoferritin Profile in Normal and Malignant Human Breast Cell Lines  

Microsoft Academic Search

We studied the mode of iron transport and storage in a human breast cancer cell line (HT-24) in comparison with a breast epithelial cell line (HBL-100). It was found that HT-24 cells incorporated over 18 h more 59Fe as compared to HBL-100 (24 vs. 16%). Yet, the number of surface transferrin-binding sites was less in cancer cells (6.2 × 105)

Nava Shterman; Batya Kupfer; Chaya Moroz

1991-01-01

198

Effect of aluminum content on environmental embrittlement in binary iron-aluminum alloys--Acoustic emission analysis  

SciTech Connect

Intermetallic iron aluminide tensile coupons with 8.5 wt% (16.1 at. %) aluminum were shown to be ductile at room temperature through the use of acoustic emission analysis combined with fractography. Room temperature brittleness of alloys with greater than 12 wt % (22 at. %) aluminum has deterred acceptance as structural materials. The cause of room temperature brittleness in iron aluminides has been determined to be a chemical reaction between the aluminum component and water vapor in the environment. All materials emit sound when stressed to the point of permanent, microscopic change. For metals and alloys this sound has frequencies in the MHz range, but is detectable by ultrasonic methods. The detected ultrasound is termed acoustic emission (AE). Terminology associated with the study of AE is idiomatic. An AE hit refers to continuous detection of ultrasound by one transducer. The amplitude, rise time, duration, ring-down count, and acoustic energy of the hit are characteristic of the microscopic, physical activity taking place, but are unique for each specimen-apparatus system. Since each specimen is unique on a microscopic level, one test constitutes a study. One- to four-thousand data points are typical for an iron aluminide specimen. The individual hit shows that a permanent change has taken place, and the cause of that change can be sought through standard micrographic methods. Tensile studies have been reported elsewhere and this work is a continuation of these studies.

Woodyard, J.R. (Bureau of Mines, Albany, OR (United States)); Sikka, V.K. (Oak Ridge National Lab., Oak Ridge, TN (United States))

1993-12-01

199

Comparison of protoporphyrin IX content and related gene expression in the tissues of chickens laying brown-shelled eggs.  

PubMed

Protoporphyrin IX (PpIX), an immediate precursor of heme, is the main pigment resulting in the brown coloration of eggshell. The brownness and uniformity of the eggshell are important marketing considerations. In this study, 9 chickens laying darker brown shelled eggs and 9 chickens laying lighter brown shelled eggs were selected from 464 individually caged layers in a Rhode Island Red pureline. The PpIX contents were measured with a Microplate Reader at the wavelength of 412 nm and were compared in different tissues of the 2 groups. Although no significant difference in serum, bile, and excreta was found between the 2 groups, PpIX content in the shell gland and eggshell of the darker group was higher than in those of the lighter group, suggesting that PpIX was synthesized in the shell gland. We further determined the expression levels of 8 genes encoding enzymes involved in the heme synthesis and transport in the liver and shell gland at 6 h postoviposition by quantitative PCR. The results showed that expression of aminolevulinic acid synthase-1 (ALAS1) was higher in the liver of hens laying darker brown shelled eggs, whereas in the shell gland the expression levels of ALAS1, coproporphyrinogen oxidase (CPOX), ATP-binding cassette family members ABCB7 and ABCG2, and receptor for feline leukemia virus, subgroup C (FLVCR) were significantly higher in the hens laying darker brown shelled eggs. Our results demonstrated that hens laying darker brown shelled eggs could deposit more PpIX onto the eggshell and the brownness of the eggshell was dependent on the total quantity of PpIX in the eggshell. More heme was synthesized in the liver and shell gland of hens laying darker brown shelled eggs than those of hens laying lighter brown shelled eggs. High expression level of ABCG2 might facilitate the accumulation of PpIX in the shell gland. PMID:24235220

Li, Guangqi; Chen, Sirui; Duan, Zhongyi; Qu, Lujiang; Xu, Guiyun; Yang, Ning

2013-12-01

200

Impact of pre-treatment prostate tissue androgen content on the prediction of castration-resistant prostate cancer development in patients treated with primary androgen deprivation therapy.  

PubMed

Great advances in tissue androgen analysis using liquid chromatography-tandem mass spectrometry (LC-MS/MS) have made it possible to evaluate the tissue androgen content from a single needle prostate biopsy specimen. In this study, we investigated if pre-treatment androgen content in prostate biopsy specimens could predict their response to primary androgen deprivation therapy (ADT) and future castration-resistant prostate cancer (CRPC). One-hundred and sixty-five prostate cancer patients who received primary ADT were enrolled. They had received multiple core prostate needle biopsy at diagnosis, and an additional one needle biopsy specimen was obtained for tissue androgen determination using LC-MS/MS. The patients' prostate specific antigen (PSA) values were periodically followed during the treatment and patients were determined to have CRPC when their PSA value increased continuously to 25% above the nadir and a 2.0 ng/mL increase. A significant correlation was found between PSA value decline velocity (PSA half-time) after ADT and pre-ADT tissue androgen content. Twenty-three patients were determined to have CRPC. These CRPC patients had a significantly high concentration of tissue T (p < 0.01) and low concentration of tissue 5?-dihydrotestosterone (DHT) (p < 0.01), resulting in a higher tissue T/DHT ratio (p < 0.001). A multivariate Cox proportional hazard model revealed the pre-ADT tissue T/DHT ratio and Gleason score as independent predictors for CRPC development. By using the two statistically significant variables, the relative risk of CRPC development could be calculated. The results of this study suggest that the evaluation of prostate androgen content in a single needle biopsy specimen may be useful to predict future CRPC development after primary ADT. Further studies are required for the clinical application of T/DHT ratio evaluation. PMID:23444052

Shibata, Y; Suzuki, K; Arai, S; Miyoshi, Y; Umemoto, S; Masumori, N; Kamiya, N; Ichikawa, T; Kitagawa, Y; Mizokami, A; Sugimura, Y; Nonomura, N; Sakai, H; Honma, S; Kubota, Y

2013-05-01

201

Fast and high-resolution quantitative mapping of tissue water content with full brain coverage for clinically-driven studies.  

PubMed

An efficient method for obtaining longitudinal relaxation time (T1) maps is based on acquiring two spoiled gradient recalled echo (SPGR) images in steady states with different flip angles, which has also been extended, with additional acquisitions, to obtain a tissue water content (M0) map. Several factors, including inhomogeneities of the radio-frequency (RF) fields and low signal-to-noise ratios may negatively affect the accuracy of this method and produce systematic errors in T1 and M0 estimations. Thus far, these limitations have been addressed by using additional measurements and applying suitable corrections; however, the concomitant increase in scan time is undesirable for clinical studies. In this note, a modified dual-acquisition SPGR method based on an optimization of the sequence formulism is presented for good and reliable M0 mapping with an isotropic spatial resolution of 1×1×1mm(3) that covers the entire human brain in 6:30min. A combined RF transmit/receive map is estimated from one of the SPGR scans and the optimal flip angles for M0 map are found analytically. The method was successfully evaluated in eight healthy subjects producing mean M0 values of 69.8% (in white matter) and 80.1% (in gray matter) that are in good agreement with those found in the literature and with high reproducibility. The mean value of the resultant voxel-based coefficients-of-variation was 3.6%. PMID:24050900

Sabati, Mohammad; Maudsley, Andrew A

2013-12-01

202

DNA, RNA and protein content of tissue during growth and embryogenesis in wild-carrot suspension cultures.  

PubMed

A highly selected population of cells (clumps from 63 to 125 micron in diameter), obtained by screening 14-day-old stock suspension cultures of wild carrot (Daucus carota L.), was used to initiate cultures in this study. Time-course changes in DNA, RNA and protein were followed when these cultures were grown in the presence or absence of 2.25 muM 2,4-dichlorophenoxyacetic acid (2,4-D). The data show that growth of these cultures, particularly in the early part of the growth curve, is different from that in most other studies reported on suspension cultures initiated without screening. The gross compositional analysis shows that this difference stems from the very high RNA:DNA and protein: DNA ratios of the cellular material used as the inoculum in this study. The presence of 2,4-D in the medium promoted total RNA and protein levels. Correlations were sought between the appearance of embryos in the absence of exogenous 2,4-D and gross compositional differences developing in cultures grown in the presence and absence of 2,4-D. The handling of cultures during inoculation appeared to have led to a substantial loss of DNA. This had, however, little effect on dry weight or protein content of the tissue. PMID:669724

Verma, D C; Dougall, D K

1978-02-01

203

Elevated expression of connective tissue growth factor, osteopontin and increased collagen content in human ascending thoracic aortic aneurysms.  

PubMed

Little is known about the molecular mechanisms of ascending thoracic aortic aneurysms (ATAAs). Abnormal extracellular matrix changes and variations of vascular smooth muscle cells (VSMCs) have been implicated in abdominal aortic aneurysm formation. Our objective was to investigate the alterations of collagen, stimulators of collagen synthesis and synthetic VSMCs in patients with ATAA. Surgical samples from ATAA were taken from 20 patients, and 18 control aortas were obtained during coronary artery bypass surgery. All aortic wall specimens were fixed for histology and immunohistochemistry for collagen, connective tissue growth factor (CTGF) and osteopontin. Realtime polymerase chain reaction was used to determine their mRNA expression. Histology and semi- quantitative analysis demonstrated that protein levels of collagen, CTGF and osteopontin significantly increased by 1.9-, 1.4- and 2.2-fold, respectively (P< 0.01 for all) in the ATAA group than in the control group. Similar results were shown in mRNA levels of type laland Illal collagen, CTGF and osteopontin. The protein levels of CTGF and osteopontin were positively correlated with aortic diameter (r= 0.67, r= 0.73; P< 0.01 for both). In conclusion, overexpression of aortic CTGF and synthetic VSMCs marker (osteopontin), which is likely to be responsible for elevated aortic collagen content, may provide a potential mechanism for aneurysmal enlargement. PMID:23508392

Meng, Y H; Tian, C; Liu, L; Wang, L; Chang, Q

2014-02-01

204

Effects of rutin supplementation on antioxidant status and iron, copper, and zinc contents in mouse liver and brain  

Microsoft Academic Search

The effect of rutin on total antioxidant status as well as on trace elements such as iron, copper, and zinc in mouse liver\\u000a and brain were studied. Mice were administrated with 0.75 g\\/kg or 2.25 g\\/kg P. O. of rutin for 30 d consecutively. Following\\u000a the treatment, the activity of total antioxidant status, catalase, Cu,Zn-superoxide dismutase, Mn-superoxide dismutase, zinc,\\u000a copper,

Zhonghong Gao; Huibi Xu; Kaixun Huang

2002-01-01

205

No correlation between changes in fatty acid-binding protein content and fatty acid oxidation capacity of rat tissues in experimental diabetes  

Microsoft Academic Search

Fatty acid-binding protein is considered to play an important role in fatty acid oxidation. Since diabetes mellitus causes marked changes of this latter metabolic process, we compared the effect of this pathological condition on both parameters in a comparative investigation of different rat tissues. Palmitate oxidation capacity and content of fatty acid-binding protein were determined in liver, heart and quadriceps

J. H. Veerkamp; H. T. B. Van Moerkerk; J. Van Den Born

1996-01-01

206

Effects of CO 2 concentration and moisture content of sugar-free media on the tissue-cultured plantlets in a large growth chamber  

NASA Astrophysics Data System (ADS)

The dynamic fluctuations of CO 2 concentration in the tissue culture growth chamber after transplantation of petunia, chrysanthemum and tomato plantlets were recorded with a real-time control system to determine the critical CO 2 concentration levels of 35 ?l l -1 at which CO 2 enrichment is needed. The experimental data showed that the tissue-cultured plantlets of petunia, chrysanthemum and tomato had the same CO 2 concentration dynamics. The results indicated that CO 2 enrichment was proper on the second day after transplantation. Petunia plantlets were used to conduct experiments under PPFD of 80 ?mol m -2 s -1, and CO 2 concentrations of 350 ± 50 ?l l -1, 650 ± 50 ?l l -1 and 950 ± 50 ?l l -1 as well as medium moisture contents of 60%, 70% and 80%, with the result that plantlets grew better under CO 2 concentration of 650 ± 50 ?l l -1 than under the other two concentrations with all the different media water contents. Three media water contents under the same CO 2 concentration produced plantlets with the same quality. The impacts of CO 2 concentrations on plantlets are more important than those of the media water contents. Sugar-free tissue culture, as compared with the conventional culture, showed that CO 2 enrichment to 350 ± 50 ?l l -1 can promote the growth of the cultured plantlets. Sugar-free tissue culture produced healthy plantlets with thick roots, almost equivalent to the common plantlets.

Qu, Y. H.; Lin, C.; Zhou, W.; Li, Y.; Chen, B.; Chen, G. Q.

2009-01-01

207

Wheat (Triticum aestivum) NAM proteins regulate the translocation of iron, zinc, and nitrogen compounds from vegetative tissues to grain  

Microsoft Academic Search

The NAM-B1 gene is a NAC transcription factor that affects grain nutrient concentrations in wheat (Triticum aestivum). An RNAi line with reduced expression of NAM genes has lower grain protein, iron (Fe), and zinc (Zn) concentrations. To determine whether decreased remobilization, lower plant uptake, or decreased partitioning to grain are responsible for this phenotype, mineral dynamics were quantified in wheat

Brian M. Waters; Cristobal Uauy; Jorge Dubcovsky; Michael A. Grusak

2009-01-01

208

Effect of fat content on single- and dual-energy CT measurements of bone mineral: determination using a new system of tissue-mimicking phantom materials  

NASA Astrophysics Data System (ADS)

The effects of fat content on single- and dual-energy CT measurements of bone mineral were quantified using a set of tissue-mimicking phantoms which more accurately represents the in-vivo situation than previous phantoms. The key to performing these measurements in CT is to have a mixture of tissue types within each image voxel, a condition which is not satisfied with standard phantoms. The phantoms used in these studies were solid materials which mimicked 17 different homogeneous mixtures of bone, muscle, and fat. The concept of creating phantoms to mimic different mixtures of these tissues is new. The materials are epoxy-resin based and have different mixtures of phenolic microspheres, polyethylene, and calcium carbonate suspended in them. Single- and dual-energy CT were used to image the phantom materials, and the effects of fat content on bone-mineral measurements were determined. The single-energy CT measurements show how fat content causes an underestimation of the amount of bone mineral present in a specimen, with the underestimation increasing as a function of fat content. With 25% and 50% fat by volume, the single-energy measurements underestimated bone volume percentage by 2.7% and 3.6% respectively. With dual-energy CT, fat content has no effect on the measurement of bone mineral. These results are not surprising. In fact, the effects of fat content on single- and dual-energy CT measurements have been studied many times previously. However, a system of accurately measuring these effects using a set of phantom measurements with physiologically accurate tissue-mimicking materials has not been developed previously. Using these phantoms, dual-energy CT measurements can be accurately calibrated for measurements of bone mineral while the errors possible while measuring bone mineral with single-energy CT can be quantified for any given imaging parameters.

Westmore, Michael S.; Sato, Masahjiko

2000-04-01

209

Flow injection flame atomic absorption spectrometry for slurry atomization. Determination of iron, calcium and magnesium in samples with high silica content.  

PubMed

A study on the use of slurries in flame atomic absorption spectrometry is reported. Samples with a very high silica content are ground and then slurried in a solution containing 2% hydrochloric and 3% v/v hydrofluoric acids. The suspensions are prepared in the 0.01-1% m/v range and introduced into the flame by means of a simple flow injection manifold. Relative standard deviations for the measurements of iron, calcium and magnesium in diatomaceous earth samples are in the 1.5-2.8, 2.2-5.3 and 2.8-5.0% ranges, respectively. To avoid the use of suspensions prepared with a very low percentage of solid sample and to improve the reproducibility, an on-line dilution manifold is tried. The use of an easy-to-construct variable volume dilution chamber allows the on-line dilution of the slurries, thus permitting the determination of calcium and magnesium over a wide range of concentrations. Calibration is performed using aqueous standards. The experimental conditions, optimized for the determination of iron, calcium and magnesium in diatomaceous earth samples, can also be applied to other silica-based materials, as is shown by the analysis of several standard reference materials. PMID:18965839

García, I L; Cortéz, J A; Córdoba, M H

1993-11-01

210

The effect of iron content and dissolved O2 on dissolution rates of clinopyroxene at pH 5.8 and 25??C: Preliminary results  

USGS Publications Warehouse

Dissolution experiments using augite (Mg087Ca0.85Fe0.19Na0.09Al 0.03Si2O6) and diopside (Mg0.91Ca0.93Fe0.07Na0.03Al 0.03Si2O6) were conducted in flow-through reactors (5-ml/h flow rate). A pH of 5.8 was maintained by bubbling pure CO2 through a solution of 0.01 M KHCO3 at 25??C. Two experiments were run for each pyroxene type. In one experiment dissolved O2 concentration in reactors was 0.6 (??0.1) ppm and in the second dissolved O2 was 1.5 (??0.1) ppm. After 60 days, augite dissolution rates (based on Si release) were approximately three times greater in the 1.5 ppm dissolved O2 experiments than in the sealed experiments. In contrast, diopside dissolution rates were independent of dissolved O2 concentrations. Preliminary results from the augite experiments suggest that dissolution rate is directly related to oxidation of iron. This effect was not observed in experiments performed on iron-poor diopside. Additionally, dissolution rates of diopside were much slower than those of augite, again suggesting a relationship between Fe content, Fe oxidation and dissolution rates.

Hoch, A. R.; Reddy, M. M.; Drever, J. I.

1996-01-01

211

Associations between the fatty acid content of triglyceride, visceral adipose tissue accumulation, and components of the insulin resistance syndrome.  

PubMed

Many factors are involved in the development of the insulin resistance syndrome, such as visceral obesity and the type of dietary fat. The main purpose of this study was to investigate the relationships between fatty acid content of triglyceride (TG), visceral adipose tissue (AT) accumulation, and metabolic components of the insulin resistance syndrome in a group of 97 Caucasian men with a mean age of 45.1 +/- 7.2 years (29 to 63 years). To reach these objectives, Spearman correlations, group comparisons, and stepwise multiple regression analyses were performed. The proportion of palmitic acid (16:0) in the TG fraction was positively associated with plasma fasting insulin (r =.25, P =.03), diastolic (r =.45, P <.001), and systolic (r =.29, P =.003) blood pressure. On the other hand, the proportion of alpha-linolenic acid (18:3n-3) was associated negatively with apolipoprotein (apo) B (r = -.29, P =.005) and positively with low-density lipoprotein (LDL) diameter (r =.29, P =.007), while the proportion of gamma-linolenic acid (18:3n-6) was associated negatively with plasma TG (r = -.33, P =.003), diastolic (r = -.29, P =.01), and systolic (r = -.35, P =.002) blood pressure and plasma fasting insulin (r = -.37, P =.0005) and positively with high-density lipoprotein (HDL)(2)-cholesterol (r =.27, P =.01) and LDL diameter (r =.25, P =.02). Stepwise multiple regression analyses were conducted to determine the contribution of visceral AT, body fat mass, and the fatty acid content of TG to the variance of metabolic variables studied. It was found that visceral AT contributed significantly to the variance in plasma TG (R(2) = 20.7%, P <.0001), apo B (R(2) = 9.0%, P =.007), HDL(2)-cholesterol (R(2) = 17.9%, P <.0001), LDL diameter (R(2) = 4.9%, P =.02), and area under the glucose curve (AUC-glucose) (R(2) = 8.2%, P =.006). On the other hand, body fat mass contributed significantly to the variance in fasting insulin (R(2) = 19.7%, P <.0001) and diastolic (R(2) = 6.8%, P =.007) and systolic (R(2) = 10.5%, P =.01) blood pressure. At least one fatty acid made a significant contribution to the variance of each metabolic variable studied. In fact, the proportion of 18:3n-6 contributed significantly to the variance in both TG (R(2) = 8.9%, P = 0.007) and HDL(2)-cholesterol (R(2) = 6.0%, P =.01). Moreover, 18:3n-3 contributed to the variance of apo B (R(2) = 7.0%, P =.02), while 18:3n-6 made the largest contribution to the variance of LDL diameter (R(2) = 7.6%, P =.02). Finally, 16:0 significantly contributed to the variance of AUC-glucose (R(2) = 11.4%, P =.0003), diastolic (R(2) = 25.2%, P <.0001), and systolic (R(2) = 6.8%, P =.002) blood pressure. In summary, results of this study suggest that the fatty acid content of TG is associated with many metabolic variables of the insulin resistance syndrome independently of body fat mass or visceral AT accumulation. PMID:15015142

Tremblay, André J; Després, Jean-Pierre; Piché, Marie-Eve; Nadeau, André; Bergeron, Jean; Alméras, Natalie; Tremblay, Angelo; Lemieux, Simone

2004-03-01

212

The Effects of Cladding Chemical Composition on Corrosion Behavior of High Burnup BWR Fuel (Corrosion Properties of Low Iron and Low Silicon Content Cladding)  

SciTech Connect

A pool-side oxide thickness measurement campaign for a number of high burnup fuels in some Japanese commercial BWRs has been conducted, in order to study a higher oxide thickness phenomenon observed on a high burnup 9x9 fuel Type B, which was fabricated by NFI and was irradiated in a BWR of TEPCO. The results showed that the combination of cladding chemical composition, irradiation period and coolant environment affected the corrosion behavior of fuel cladding. Cladding with low iron and low silicon content, which has been shown to have inferior corrosion properties, is no longer used for the fuel assemblies loaded in operating Japanese BWRs today and in the future, so this kind of cladding corrosion phenomenon will not occur. This paper describes the results of the oxide thickness measurement, which was performed as a joint study by TEPCO and NFI. (authors)

Otsuka, Yasuyuki; Abe, Moriyasu [Tokyo Electric Power Company (TEPCO), 1-1-3, Uchisaiwai-cho, Chiyoda-ku, Tokyo 100-8560 (Japan); Kakiuchi, Kazuo; Fukuda, Takuji; Ohira, Koichi; Itagaki, Noboru [Nuclear Fuel Industries, Ltd. (NFI), 3135-41, Muramatsu, Tokai-mura, Naka-gun, Ibaraki 319-1196 (Japan)

2007-07-01

213

HEPCIDIN AND IRON HOMEOSTASIS  

PubMed Central

Despite fluctuations in dietary iron intake and intermittent losses through bleeding, the plasma iron concentrations in humans remain stable at 10–30 ?M. While most of the iron entering blood plasma comes from recycling, appropriate amount of iron is absorbed from the diet to compensate for losses and maintain nontoxic amounts in stores. Plasma iron concentration and iron distribution are similarly regulated in laboratory rodents. The hepatic peptide hepcidin was identified as the systemic iron-regulatory hormone. In the efferent arc, hepcidin regulates intestinal iron absorption, plasma iron concentrations, and tissue iron distribution by inducing degradation of its receptor, the cellular iron exporter ferroportin. Ferroportin exports iron into plasma from absorptive enterocytes, from macrophages that recycle the iron of senescent erythrocytes, and from hepatocytes that store iron. In the more complex and less well understood afferent arc, hepatic hepcidin synthesis is transcriptionally regulated by extracellular and intracellular iron concentrations through a molecular complex of bone morphogenetic protein receptors and their iron-specific ligands, modulators and iron sensors. Through as yet undefined pathways, hepcidin is also homeostatically regulated by the iron requirements of erythroid precursors for hemoglobin synthesis. In accordance with the role of hepcidin-mediated iron redistribution in host defense, hepcidin production is regulated by inflammation as well. Increased hepcidin concentrations in plasma are pathogenic in iron-restrictive anemias including anemias associated with inflammation, chronic kidney disease and some cancers. Hepcidin deficiency causes iron overload in hereditary hemochromatosis and ineffective erythropoiesis. Hepcidin, ferroportin and their regulators represent potential targets for the diagnosis and treatment of iron disorders and anemias.

Ganz, Tomas; Nemeth, Elizabeta

2014-01-01

214

US Transuranium Registry report of the 241Am content of a whole body. Part IV: Preparation and analysis of the tissues and bones  

SciTech Connect

Los Alamos National Laboratory has analyzed autopsy tissue for the USTR, as a part of its study of the uptake, distribution and retention of Pu and other transuranic elements in occupationally exposed workers since 1978. In April 1979, Los Alamos received the internal organs and bone samples from the first whole-body donation to the USTR. The donor was known to have an internal deposition of SU Am. All soft tissue, the bones from the right half of the skeleton, and the odd-numbered vertebrae were received at Los Alamos in February 1980. The bones were subdivided along anatomical areas of interest. All soft tissues and bone specimens were analyzed for their SU Am content. A total deposition of 147.4 nCi SU Am was measured. Approximately 18% of the SU Am remaining in the body (disregarding that in the left hand), was found in the soft tissues, and 82% was in the bones and teeth. The soft tissues and organs containing the largest amounts of SU Am were the combined soft tissue (striated muscle, connective tissue and skin) 8.8%; liver, 6.4% and respiratory tract, 1.5%. The remaining organs accounted for 0.9% of the systemic burden.

McInroy, J.F.; Boyd, H.A.; Eutsler, B.C.; Romero, D.

1985-10-01

215

Evaluation of the content and bioaccessibility of iron, zinc, calcium and magnesium from groats, rice, leguminous grains and nuts.  

PubMed

The objective of this study was to determine the content and the bioaccessibility of minerals (Fe, Zn, Ca and Mg) in commonly consumed food products, such as cereal groats, rice, leguminous grains and nuts purchased from the local market. The contents of Fe, Zn, Ca and Mg in foods were assayed after dry ashing of samples, while the bioaccessibility of these minerals after enzymatic in vitro digestion, was determined by flame atomic absorption spectrometry. A relatively high content of Fe was found in cashew nuts and green lentils, while cashew nuts and buckwheat groats had the highest concentration of Zn. It was found that the highest amount of macro-elements was generally in nuts, in particular: brazil nuts (Ca and Mg), cashews (Mg) and hazelnuts (Ca and Mg). Concerning the mineral bioaccessibility, the highest values for Fe were obtained in cashew nuts and green lentils (2.8 and 1.7 mg/100 g), for Zn in green lentils (2.1 mg/100 g), for Ca in brazil nuts and shelled pea (32.6 and 29.1 mg/100 g), while for Mg in shelled peas and green lentils (43.4 and 33.9 mg/100 g). Generally, the best sources of bioaccessible minerals seem to be leguminous grains and nuts. PMID:24587537

Suliburska, Joanna; Krejpcio, Zbigniew

2014-03-01

216

Insulin sensitizer YM268 ameliorates insulin resistance by normalizing the decreased content of GLUT4 in adipose tissue of obese Zucker rats  

Microsoft Academic Search

Genetically obese Zucker rats exhibit mild hyperglycaemia and hyperinsulinaemia suggesting the existence of peripheral insulin resistance. We have examined the effects of YM268, an analogue of thiazolidinedione, on the content and translocation of a glucose transporter (GLUT4) in epididymal adipose tissue in 11-week-old obese and lean Zucker rats. The administration of YM268 at a dose of 10 mg\\/kg for 2

Akiyoshi Shimaya; Osamu Noshiro; Reiko Hirayama; Takashi Yoneta; Kunihiro Niigata; Hisataka Shikama

1997-01-01

217

Treatment of rats with a self-selected hyperlipidic diet, increases the lipid content of the main adipose tissue sites in a proportion similar to that of the lipids in the rest of organs and tissues.  

PubMed

Adipose tissue (AT) is distributed as large differentiated masses, and smaller depots covering vessels, and organs, as well as interspersed within them. The differences between types and size of cells makes AT one of the most disperse and complex organs. Lipid storage is partly shared by other tissues such as muscle and liver. We intended to obtain an approximate estimation of the size of lipid reserves stored outside the main fat depots. Both male and female rats were made overweight by 4-weeks feeding of a cafeteria diet. Total lipid content was analyzed in brain, liver, gastrocnemius muscle, four white AT sites: subcutaneous, perigonadal, retroperitoneal and mesenteric, two brown AT sites (interscapular and perirenal) and in a pool of the rest of organs and tissues (after discarding gut contents). Organ lipid content was estimated and tabulated for each individual rat. Food intake was measured daily. There was a surprisingly high proportion of lipid not accounted for by the main macroscopic AT sites, even when brain, liver and BAT main sites were discounted. Muscle contained about 8% of body lipids, liver 1-1.4%, four white AT sites lipid 28-63% of body lipid, and the rest of the body (including muscle) 38-44%. There was a good correlation between AT lipid and body lipid, but lipid in "other organs" was highly correlated too with body lipid. Brain lipid was not. Irrespective of dietary intake, accumulation of body fat was uniform both for the main lipid storage and handling organs: large masses of AT (but also liver, muscle), as well as in the "rest" of tissues. These storage sites, in specialized (adipose) or not-specialized (liver, muscle) tissues reacted in parallel against a hyperlipidic diet challenge. We postulate that body lipid stores are handled and regulated coordinately, with a more centralized and overall mechanisms than usually assumed. PMID:24603584

Romero, María Del Mar; Roy, Stéphanie; Pouillot, Karl; Feito, Marisol; Esteve, Montserrat; Grasa, María Del Mar; Fernández-López, José-Antonio; Alemany, Marià; Remesar, Xavier

2014-01-01

218

Treatment of Rats with a Self-Selected Hyperlipidic Diet, Increases the Lipid Content of the Main Adipose Tissue Sites in a Proportion Similar to That of the Lipids in the Rest of Organs and Tissues  

PubMed Central

Adipose tissue (AT) is distributed as large differentiated masses, and smaller depots covering vessels, and organs, as well as interspersed within them. The differences between types and size of cells makes AT one of the most disperse and complex organs. Lipid storage is partly shared by other tissues such as muscle and liver. We intended to obtain an approximate estimation of the size of lipid reserves stored outside the main fat depots. Both male and female rats were made overweight by 4-weeks feeding of a cafeteria diet. Total lipid content was analyzed in brain, liver, gastrocnemius muscle, four white AT sites: subcutaneous, perigonadal, retroperitoneal and mesenteric, two brown AT sites (interscapular and perirenal) and in a pool of the rest of organs and tissues (after discarding gut contents). Organ lipid content was estimated and tabulated for each individual rat. Food intake was measured daily. There was a surprisingly high proportion of lipid not accounted for by the main macroscopic AT sites, even when brain, liver and BAT main sites were discounted. Muscle contained about 8% of body lipids, liver 1–1.4%, four white AT sites lipid 28–63% of body lipid, and the rest of the body (including muscle) 38–44%. There was a good correlation between AT lipid and body lipid, but lipid in “other organs” was highly correlated too with body lipid. Brain lipid was not. Irrespective of dietary intake, accumulation of body fat was uniform both for the main lipid storage and handling organs: large masses of AT (but also liver, muscle), as well as in the ”rest” of tissues. These storage sites, in specialized (adipose) or not-specialized (liver, muscle) tissues reacted in parallel against a hyperlipidic diet challenge. We postulate that body lipid stores are handled and regulated coordinately, with a more centralized and overall mechanisms than usually assumed.

Romero, Maria del Mar; Roy, Stephanie; Pouillot, Karl; Feito, Marisol; Esteve, Montserrat; Grasa, Maria del Mar; Fernandez-Lopez, Jose-Antonio; Alemany, Maria; Remesar, Xavier

2014-01-01

219

[Diagnosis of iron overload syndrome].  

PubMed

The article presents a classification of conditions, accompanied with increasing of iron accumulation of the liver cells, normal iron metabolism in the human body, etiology, epidemiology, multifactorial structure of the pathogenesis of HFE homozygous hemochromatosis, clinic of iron overload syndrome. The modern algorithms of diagnostic and tactics of patients with the use of genotyping and correction of iron content. PMID:20731136

Polunina, T E; Maev, I V

2010-01-01

220

Effect of phlebotomy on the ferritin iron content in the rat liver as determined morphometrically with the use of electron energy loss spectroscopy  

Microsoft Academic Search

Phlebotomy of untreated and iron-loaded rats results in a significant decrease in total liver iron. In ironloaded rats a marked decrease in iron-containing particles is observed ultrastructurally in lysosomes and cytoplasm of hepatic sinusoidal cells but not in parenchymal cells. This remarkable phenomenon was further investigated in a morphometric study, based on element-specific (iron) distribution images made in situ in

M. I. Cleton; L. J. Mostert; L. W. J. Sorber; A. A. W. de Jong; C. M. H. de Jeu-Jaspars; W. C. de Bruijn

1989-01-01

221

Content and Redistribution of Vitamin E in Tissues of Wistar Rats Under Oxidative Stress Induced by Hydrazine  

Microsoft Academic Search

Hydrazine toxicity is associated with generation of several kinds of free radicals and oxidative stress in cell. Experiments\\u000a in vivo have demonstrated that oxidative stress could either diminish or increase concentration of vitamin E in some tissues. Thus\\u000a in the present study we performed experiments to determine whether hydrazine-induced oxidative stress would change the tissue\\u000a levels of the vitamin. Seven

A. Matuszkiewicz; R. A. Olek; J. J. Kaczor; W. Zió?kowski; T. Wakabayashi; J. Popinigis

2002-01-01

222

Antioxidant Capacity and Total Phenolic Content in Fruit Tissues from Accessions of Capsicum chinense Jacq. (Habanero Pepper) at Different Stages of Ripening  

PubMed Central

In the past few years, there has been a renewed interest in studying a wide variety of food products that show beneficial effects on human health. Capsicum is an important agricultural crop, not only because its economic importance, but also for the nutritional values of its pods, mainly due to the fact that they are an excellent source of antioxidant compounds, and also of specific constituents such as the pungent capsaicinoids localized in the placental tissue. This current study was designed to evaluate the antioxidant capacity and total phenolic contents from fruits tissues of two Capsicum chinense accessions, namely, Chak k'an-iik (orange) and MR8H (red), at contrasting maturation stages. Results showed that red immature placental tissue, with a Trolox equivalent antioxidant capacity (TEAC) value of 55.59??mols?TE?g?1?FW, exhibited the strongest total antioxidant capacity using both the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and the CUPRAC methods. Placental tissue also had the highest total phenolic content (27?g GAE 100?g?1?FW). The antioxidant capacity of Capsicum was directly related to the total amount of phenolic compounds detected. In particular, placentas had high levels of capsaicinoids, which might be the principal responsible for their strong antioxidant activities.

Tuyub-Che, Jemina; Moo-Mukul, Angel; Vazquez-Flota, Felipe A.; Miranda-Ham, Maria L.

2014-01-01

223

Antioxidant capacity and total phenolic content in fruit tissues from accessions of Capsicum chinense Jacq. (Habanero pepper) at different stages of ripening.  

PubMed

In the past few years, there has been a renewed interest in studying a wide variety of food products that show beneficial effects on human health. Capsicum is an important agricultural crop, not only because its economic importance, but also for the nutritional values of its pods, mainly due to the fact that they are an excellent source of antioxidant compounds, and also of specific constituents such as the pungent capsaicinoids localized in the placental tissue. This current study was designed to evaluate the antioxidant capacity and total phenolic contents from fruits tissues of two Capsicum chinense accessions, namely, Chak k'an-iik (orange) and MR8H (red), at contrasting maturation stages. Results showed that red immature placental tissue, with a Trolox equivalent antioxidant capacity (TEAC) value of 55.59 ?mols TE g(-1) FW, exhibited the strongest total antioxidant capacity using both the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and the CUPRAC methods. Placental tissue also had the highest total phenolic content (27 g GAE 100 g(-1) FW). The antioxidant capacity of Capsicum was directly related to the total amount of phenolic compounds detected. In particular, placentas had high levels of capsaicinoids, which might be the principal responsible for their strong antioxidant activities. PMID:24683361

Castro-Concha, Lizbeth A; Tuyub-Che, Jemina; Moo-Mukul, Angel; Vazquez-Flota, Felipe A; Miranda-Ham, Maria L

2014-01-01

224

Multiregional brain iron deficiency in restless legs syndrome.  

PubMed

Evidence for tissue iron deficiency in restless legs syndrome (RLS) is limited to the substantia nigra (SN). Using MRI, we assessed T2 values of various brain regions in 6 RLS patients and 19 controls and correlated them with sonographically assessed SN echogenicity. Both neuroimaging features are supposed to correlate with tissue iron content. Mean T2 values of all regions were higher in patients (2.9-7.8%), though significantly increased only in four regions; the mean T2 over all voxels was higher in patients (5.1%, P < 0.001) and correlated inversely with SN echogenicity (r = -0.61, P < 0.001). This indicates multiregional (global) brain iron deficiency in RLS and proposes SN echogenicity as a potential morphological marker for brain iron status. (c) 2008 Movement Disorder Society. PMID:18442125

Godau, Jana; Klose, Uwe; Di Santo, Adriana; Schweitzer, Katherine; Berg, Daniela

2008-06-15

225

The Iron-Storage Diseases.  

National Technical Information Service (NTIS)

Idiopathic, generalized, massive iron overloading (hemochromatosis) is a familial disorder in which excessive amounts of dietary iron are absorbed and accumulate in various organs of the body to produce tissue damage. Usually, the disease becomes manifest...

M. E. Conrad

1968-01-01

226

Iron Nutrition, Immunity and Infection.  

National Technical Information Service (NTIS)

During infection, physiological mechanisms withhold iron from invading microorganisms by sequestering it in tissue stores. These mechanisms increase the concentration of unsaturated transferrin in plasma by reducing plasma iron values. In contrast to the ...

W. R. Beisel

1980-01-01

227

Analysis of iron, zinc, selenium and cadmium in paraffin-embedded prostate tissue specimens using inductively coupled plasma mass-spectrometry  

USGS Publications Warehouse

Formalin-fixed paraffin-embedded (FFPE) tissue specimens represent a valuable and abundant resource of pathologic material for various biomedical studies. In the present study, we report the application of high-resolution inductively coupled mass-spectrometry (ICP-MS) for quantification of Fe, Zn, Se and Cd in FFPE prostate tissue. These elements have a possible role in the development of prostate diseases: while Zn and Se are needed for a healthy prostate, Cd shows multiple toxic and carcinogenic effects. Excessive accumulation of Fe induces the production of highly reactive hydroxyl radical species, which may play a role in cancer etiopathogenesis. To assess whether the levels of these metals in the FFPE prostate tissue represent their original content, we compared their levels with those in the fresh tissue (on dry weight basis) in samples obtained from 15 patients. We found that in FFPE tissue, the recoveries of Se, Fe, Cd and Zn were progressively decreased, 97??11% (r=0.88), 82??22% (r=0.86), 59??23% (r=0.69) and 24??11% (r=0.38), respectively. Thus, the use of correction factors, determined as k=0.16 for Se, k=0.20 for Fe, k=0.27 for Cd and k=0.67 for Zn, is required to estimate the retrospective levels of these elements in the parental non-processed fresh (wet) prostate tissue. The technique used in this study enables the analysis of archival FFPE prostate tissue for the concentrations of Fe, Zn, Se and Cd to study association between the levels of these metals and prostate disease. ?? 2008.

Sarafanov, A. G.; Todorov, T. I.; Kajdacsy-Balla, A.; Gray, M. A.; Macias, V.; Centeno, J. A.

2008-01-01

228

Iron and iron derived radicals  

SciTech Connect

We have discussed some reactions of iron and iron-derived oxygen radicals that may be important in the production or treatment of tissue injury. Our conclusions challenge, to some extent, the usual lines of thought in this field of research. Insofar as they are born out by subsequent developments, the lessons they teach are two: Think fastexclamation Think smallexclamation In other words, think of the many fast reactions that can rapidly alter the production and fate of highly reactive intermediates, and when considering the impact of competitive reactions on such species, think how they affect the microenvironment (on the molecular scale) ''seen'' by each reactive molecule. 21 refs., 3 figs., 1 tab.

Borg, D.C.; Schaich, K.M.

1987-04-01

229

Iron enhances the neurotoxicity of amyloid ?  

PubMed Central

Brain microbleeds often occur in Alzheimer’s disease patients. Our previous studies have demonstrated that iron contributes to brain injury following intracerebral hemorrhage. This study investigated the effect of iron on amyloid ? (A?)-mediated brain injury. There were two parts to this study. In first part, rats received an intracaudate injection of saline, iron, A? 25–35 or iron+A? 25–35. In the second part, rats received intracaudate injection of iron+A? and were treated with saline or cystamine, an inhibitor of transglutaminase. Rats were killed after 24 hours for brain edema measurement. DNA damage, neuronal death and tissue-type transglutaminase (tTG) expression were also examined. We found that brain water content in the ipsilateral caudate was higher (p<0.05) in rats injected with iron+A? than with iron, A? or saline. Combined iron+A? injection also resulted in more severe DNA damage (both single- and double-strand; p<0.01) and more Fluoro-Jade C staining (p<0.05). Expression of tTG increased markedly in the iron+A? group (p<0.05) and treatment with a tTG inhibitor reduced brain edema (p<0.05) and reduced degenerating neurons (124±25 vs. 249±50/mm2 in vehicle-treated group, p<0.05). These results suggest that increased brain iron from microbleeds may exaggerate brain A? toxicity and that tTG is involved in the enhanced toxicity.

Wang, Lin; Xi, Guohua; Keep, Richard F.; Hua, Ya

2011-01-01

230

Determination of iron in solutions containing iron complexes  

Microsoft Academic Search

A method of estimating the iron content of solutions containing haemoglobin, ferritin, or ferrioxamine is described. Iron is released by treatment with acid permanganate and ascorbic acid before conventional determination by an Auto Analyzer technique.

G. B. Tennant; D. A. Greenman

1969-01-01

231

Minor and trace elemental contents of cancerous breast tissue measured by instrumental and radiochemical neutron activation analysis.  

PubMed

Many minor and trace elements influence the permeability of cell membranes by competing for binding sites, and exert direct or indirect action on the carcinogenic process. Instrumental and radiochemical neutron activation analysis has been employed for the determination of more than 20 elements in normal and cancerous breast tissues of 6 patients. Most trace elements, viz., Zn, Cu, Mn, Co, Se, Br, As, Sb and Cd, are elevated in cancerous tissue, whereas lower levels are observed for Fe, Cs, I, and Sr. Similarly, concentrations of minor constituents, such as Na, K, P, Cl, and Mg, are enhanced compared to normal tissue. Several elements incorporate into the normal cell, change its enzymatic activity, and accelerate the growth of tumor. PMID:1704754

Garg, A N; Weginwar, R G; Sagdeo, V

1990-01-01

232

Content and redistribution of vitamin E in tissues of Wistar rats under oxidative stress induced by hydrazine.  

PubMed

Hydrazine toxicity is associated with generation of several kinds of free radicals and oxidative stress in cell. Experiments in vivo have demonstrated that oxidative stress could either diminish or increase concentration of vitamin E in some tissues. Thus in the present study we performed experiments to determine whether hydrazine-induced oxidative stress would change the tissue levels of the vitamin. Seven days of hydrazine intoxication led to accumulation of different amounts of vitamin E: 215% in the liver, 118% in the heart, 135% in the spleen, and 100% in the muscle over control value. There were no changes in the level of the vitamin in kidney and pancreas, despite its significant depletion in the serum. In tissue that accumulated vitamin E after hydrazine treatment, an increased of oxidative stress measured by the concentration of lipid-soluble fluorophore was observed. Significant increases of 107%, 46%, 72%, and 58% over control values were observed in the liver, heart, spleen, and muscle, respectively. Rats treated with hydrazine and pharmacological doses of alpha-tocopherol accumulated higher concentrations of vitamin E in all studied tissues compared with the alpha-tocopherol-only treated rats. However, in tissues with elevated levels of fluorophore as liver, heart, spleen, and muscle, the accumulation of vitamin E was 5.03, 4.5, 4.03, and 4.6 times higher than in alpha-tocopherol-treated rats, respectively. Vitamin E concentration was much higher than in kidney and pancreas, where the accumulation was only 2.31 and 2.6 times higher. On the other hand, 3 days of hydrazine treatment did not change either the level of lipid-soluble fluorophore or the level of vitamin E in the liver mitochondria, microsomes, and homogenate. In skeletal muscle vitamin E caused decreased lipofuscin accumulation, and in pancreas vitamin E increased lipofuscin accumulation. Our data indicate that hydrazine is able to modify significantly vitamin E status in different rat tissues. PMID:11910466

Antosiewicz, J; Matuszkiewicz, A; Olek, R A; Kaczor, J J; Zió?kowski, W; Wakabayashi, T; Popinigis, J

2002-04-01

233

Central leptin regulates total ceramide content and sterol regulatory element binding protein-1C proteolytic maturation in rat white adipose tissue.  

PubMed

Obesity and type 2 diabetes are associated with insulin and leptin resistance, and increased ceramide contents in target tissues. Because the adipose tissue has become a central focus in these diseases, and leptin-induced increases in insulin sensitivity may be related to effects of leptin on lipid metabolism, we investigated herein whether central leptin was able to regulate total ceramide levels and the expression of enzymes involved in ceramide metabolism in rat white adipose tissue (WAT). After 7 d central leptin treatment, the total content of ceramides was analyzed by quantitative shotgun lipidomics mass spectrometry. The effects of leptin on the expression of several enzymes of the sphingolipid metabolism, sterol regulatory element binding protein (SREBP)-1c, and insulin-induced gene 1 (INSIG-1) in this tissue were studied. Total ceramide levels were also determined after surgical WAT denervation. Central leptin infusion significantly decreased both total ceramide content and the long-chain fatty acid ceramide species in WAT. Concomitant with these results, leptin decreased the mRNA levels of enzymes involved in de novo ceramide synthesis (SPT-1, LASS2, LASS4) and ceramide production from sphingomyelin (SMPD-1/2). The mRNA levels of enzymes of ceramide degradation (Asah1/2) and utilization (sphingomyelin synthase, ceramide kinase, glycosyl-ceramide synthase, GM3 synthase) were also down-regulated. Ceramide-lowering effects of central leptin were prevented by local autonomic nervous system denervation of WAT. Finally, central leptin treatment markedly increased INSIG-1 mRNA expression and impaired SREBP-1c activation in epididymal WAT. These observations indicate that in vivo central leptin, acting through the autonomic nervous system, regulates total ceramide levels and SREBP-1c proteolytic maturation in WAT, probably contributing to improve the overall insulin sensitivity. PMID:18801905

Bonzón-Kulichenko, Elena; Schwudke, Dominik; Gallardo, Nilda; Moltó, Eduardo; Fernández-Agulló, Teresa; Shevchenko, Andrej; Andrés, Antonio

2009-01-01

234

The response of a spherical tissue-equivalent proportional counter to iron particles from 200-1000 MeV/nucleon  

NASA Technical Reports Server (NTRS)

The radiation environment on board the space shuttle and the International Space Station includes high-Z and high-energy (HZE) particles that are part of the galactic cosmic radiation (GCR) spectrum. Iron-56 particles are considered to be one of the most biologically important parts of the GCR spectrum. Tissue-equivalent proportional counters (TEPCs) are used as active dosimeters on manned space flights. These TEPCs are further used to determine the average quality factor for each space mission. A TEPC simulating a 1-microm-diameter sphere of tissue was exposed as part of a particle spectrometer to (56)Fe particles at energies from 200-1000 MeV/nucleon. The response of TEPCs in terms of mean lineal energy, y(F), and dose mean lineal energy, y(D), as well as the energy deposited at different impact parameters through the detector was determined for six different incident energies of (56)Fe particles in this energy range. Calculations determined that charged-particle equilibrium was achieved for each of the six experiments. Energy depositions at different impact parameters were calculated using a radial dose distribution model, and the results were compared to experimental data.

Gersey, B. B.; Borak, T. B.; Guetersloh, S. B.; Zeitlin, C.; Miller, J.; Heilbronn, L.; Murakami, T.; Iwata, Y.; Chatterjee, A. (Principal Investigator)

2002-01-01

235

Influence of chelation and oxidation state on vanadium bioavailability, and their effects on tissue concentrations of zinc, copper, and iron  

Microsoft Academic Search

Today, vanadium compounds are frequently included in nutritional supplements and are also being developed for therapeutic\\u000a use in diabetes mellitus. Previously, tissue uptake of vanadium from bis(maltolato)oxovanadium(IV) (BMOV) was shown to be\\u000a increased compared to its uptake from vanadyl sulfate (VS). Our primary objective was to test the hypothesis that complexation\\u000a increases vanadium uptake and that this effect is independent

Katherine H. Thompson; Yoko Tsukada; Zhaoming Xu; Mary Battell; John H. McNeill; Chris Orvig

2002-01-01

236

Evidence that an L-arginine/nitric oxide dependent elevation of tissue cyclic GMP content is involved in depression of vascular reactivity by endotoxin.  

PubMed Central

1. The aim of this investigation was to study the relationship between contractile responsiveness, activation of the L-arginine pathway and tissue levels of guanosine 3':5'cyclic monophosphate (cylic GMP) in aortic rings removed from rats 4 h after intraperitoneal administration of bacterial endotoxin (E. coli. lipopolysaccharide, LPS, 20 mg kg-1). 2. LPS-treatment resulted in a reduction of the sensitivity and maximal contractile response to noradrenaline (NA). 3. Depression of the maximal contractile response was restored to control by 6-anilo-5,8-quinolinedione (LY 83583, 10 microM), which prevents activation of soluble guanylate cyclase. 4. Cyclic GMP levels in tissue from LPS-treated rats were 2 fold greater than cyclic GMP levels detected in tissue from control (saline-treated) rats. The LPS-induced increase in cyclic GMP content was observed both in the presence and absence of functional endothelium. 5. Addition of L-arginine 1 mM) to maximally contracted aortic rings produced significantly relaxation of rings from LPS-treated rats but not rings from control animals. In the LPS-treated group, addition of L-arginine was also associated with a significant increase in cyclic GMP content. L-Arginine had no effect on the cyclic GMP content of control rings. D-Arginine (1 mM) was without effect. 6. In rings from LPS-treated rats, NG-nitro-L-arginine methyl ester (L-NAME, 300 microM), an inhibitor of nitric oxide (NO) production, increased the contractile response to NA and prevented the LPS-induced increase in cyclic GMP content.(ABSTRACT TRUNCATED AT 250 WORDS)

Fleming, I.; Julou-Schaeffer, G.; Gray, G. A.; Parratt, J. R.; Stoclet, J. C.

1991-01-01

237

Determination of digestibility, tissue deposition, and metabolism of the omega-3 fatty acid content of krill protein concentrate in growing rats.  

PubMed

Krill protein concentrate (KPC) consists of high-quality protein (77.7% dry basis) and lipids (8.1% dry basis) that are rich (27% of total fatty acids) in omega-3 polyunsaturated fatty acids (omega-3 PUFAs). The objective of the study was to determine digestibility, tissue deposition, metabolism, and tissue oxidative stability of the omega-3 PUFAs provided by KPC. Young female Sprague-Dawley rats (n = 10/group) were fed ad libitum isocaloric diets for 4 weeks with either 10% freeze-dried KPC or 10% casein. The casein diet contained 5.3% added corn oil (CO), whereas the KPC contained 5.3% total lipids from 0.9% krill oil (KO) provided by KPC and 4.4% added corn oil (KO + CO). Fatty acid compositions of various tissues were analyzed by gas chromatography. Lipid peroxidation was determined by thiobarbituric acid reactive substances (TBARS). Total antioxidant capacity and urinary eicosanoid metabolites were determined by enzyme immunoassay. The omega-3 PUFAs provided in KO from KPC increased (P = 0.003) docosahexaenoic acid (DHA) concentration in the brain. DHA and eicosapentaenoic acid (EPA) content in fat pads and liver were increased (P < 0.01), whereas the omega-6 PUFA, arachidonic acid (AA), was decreased (P < 0.01) in rats fed the KPC diet containing the KO + CO mixture compared to rats fed the casein diet containing pure CO. Feeding the KPC diet decreased pro-inflammatory 2-series prostaglandin and thromboxane metabolites. There was no significant difference in TBARS or total antioxidant capacity in the tissues of rats fed the different diets. On the basis of the study results, the low amount of omega-3 PUFAs provided by the KO content of KPC provides beneficial effects of increasing tissue EPA and DHA deposition and reduced AA-derived 2-series eicosanoid metabolites without increasing lipid peroxidation. Therefore, consumption of KPC has the potential to provide a healthy and sustainable source of omega-3 PUFAs. PMID:20131797

Bridges, Kayla M; Gigliotti, Joseph C; Altman, Stephanie; Jaczynski, Jacek; Tou, Janet C

2010-03-10

238

Specific expression of the vacuolar iron transporter, TgVit, causes iron accumulation in blue-colored inner bottom segments of various tulip petals.  

PubMed

Several flowers of Tulipa gesneriana exhibit a blue color in the bottom segments of the inner perianth. We have previously reported the inner-bottom tissue-specific iron accumulation and expression of the vacuolar iron transporter, TgVit1, in tulip cv. Murasakizuisho. To clarify whether the TgVit1-dependent iron accumulation and blue-color development in tulip petals are universal, we analyzed anthocyanin, its co-pigment components, iron contents and the expression of TgVit1 mRNA in 13 cultivars which show a blue color in the bottom segments of the inner perianth accompanying yellow- and white-colored inner-bottom petals. All of the blue bottom segments contained the same anthocyanin component, delphinidin 3-rutinoside. The flavonol composition varied with cultivar and tissue part. The major flavonol in the bottom segments of the inner perianth was rutin. The iron content in the upper part was less than that in the bottom segments of the inner perianth. The iron content in the yellow and white petals was higher in the bottom segment of the inner perianth than in the upper tissues. TgVit1 mRNA expression was apparent in all of the bottom tissues of the inner perianth. The result of a reproduction experiment by mixing the constituents suggests that the blue coloration in tulip petals is generally caused by iron complexation to delphinidin 3-rutinoside and that the iron complex is solubilized and stabilized by flavonol glycosides. TgVit1-dependent iron accumulation in the bottom segments of the inner perianth might be controlled by an unknown system that differentiated the upper parts and bottom segments of the inner perianth. PMID:22313773

Momonoi, Kazumi; Tsuji, Toshiaki; Kazuma, Kohei; Yoshida, Kumi

2012-01-01

239

Feeding diets supplemented with zinc and vitamin A in laying hens: effects on histopathological findings and tissue mineral contents  

Microsoft Academic Search

The effects of different dietary levels of zinc and vitamin A on tissue mineral accumulation and histopathological alterations were examined in laying hens. For this purpose, 130 Hisex brown laying hens aged 56 weeks were divided into two main groups. Each group of hens were fed on diets supplemented with two different levels of vitamin A (0–10000IUkg?1). Then, laying hens

Sule Kaya; M Ortatatli; S Haliloglu

2002-01-01

240

Decreased heme content and cessation of cell growth in cultured chick embryo fibroblasts in the presence of horse serum: stimulation of heme synthesis and cell growth by iron.  

PubMed

A new spectrofluorometric method for heme quantitation in cultured fibroblasts is described. The method includes: 1) heme extraction by methanol/sulfuric acid, 2) partial purification of heme by a microchromatographic method, and 3) treatment of the purified heme by oxalic acid followed by fluorometric quantitation. Using this method, heme concentration was determined in chick embryo fibroblasts cultured in a medium supplemented with either 7% fetal bovine serum (FBS) or 10% horse serum (HS). In the presence of FBS, cultured cells actively divided and cells contained 34-55 pmol heme/mg protein. In contrast, cultures maintained in HS proliferated at a slower rate and contained 23-25 pmol heme/mg protein. The addition of 40 microM FeSO4 to cultures maintained in the presence of HS stimulated cell proliferation, and the cellular heme concentration increased to 37-51 pmol/mg protein. These findings suggest that the cessation of growth in the presence of HS may be due to decreased heme content in the cells and that the stimulation of cell growth by iron is mediated by its stimulation of heme synthesis. PMID:7174727

Verger, C; Imbenotte, J

1982-11-01

241

Alterations in lignin content and phenylpropanoids pathway in date palm (Phoenix dactylifera L.) tissues affected by brittle leaf disease.  

PubMed

Brittle leaf disease or Maladie de la Feuille Cassante (MFC) is a lethal disorder of date palm that has assumed epidemic proportions in the oases of Tunisia and Algeria. No pathogen could ever be associated with the disease, while leaflets of affected palms have been previously shown to be deficient in manganese. The work reported here aims to understand the biochemical basis of the date palm response to this disorder. Since the typical disease symptom is the leaf fragility, we have investigated lignin content in leaves and roots. Strong decrease in total lignin content was observed in affected leaves, while lignin content increased in affected roots. Histochemical analyses showed hyperlignification thicker suberin layer in roots cortical cells. The phenylpropanoids pathway was also disrupted in leaves and roots, cinnamoyl-CoA reductase and cinnamyl-alcohol dehydrogenase gene expression was affected by the disease which severely affects the cell wall integrity. PMID:23987806

Saidi, Mohammed Najib; Bouaziz, Donia; Hammami, Ines; Namsi, Ahmed; Drira, Noureddine; Gargouri-Bouzid, Radhia

2013-10-01

242

Magnetic resonance imaging of iron oxide labelled stem cells: applications to tissue engineering based regeneration of the intervertebral disc.  

PubMed

Minimally-invasive monitoring of regeneration in diseased tissue is an important aspect of stem cell therapy. Magnetic resonance imaging (MRI) based tracking of cells labelled with ferumoxides has the potential for non-invasive in vivo detection and longitudinal assessment of implanted cells. Cells labelled with ferumoxides appear as hypointense regions on MR images and thus can be distinguished from the surroundings. Application of this methodology to intervertebral disc degeneration (IVD), and detection of labelled cells implanted into the disc for tissue regeneration was examined. Mesenchymal stem cells labelled with a ferumoxide contrast agent were imaged in vitro to quantitatively characterize the signal intensity loss using MRI relaxation parameters (T1, T2, and T2*). To determine whether labelled cells could be detected within scaffolds suitable for implantation, labelled cells were seeded within both natural and synthetic polymers and imaged using MRI. Labelled cells were loaded within poly(ethylene glycol) hydrogels and imaged in vitro using both MRI and confocal microscopy. Labelled cells were also loaded into fibrin gels, and detected ex vivo within rat IVDs using MRI. Lastly, the effect of ferumoxide labelling on cell viability was investigated. Quantitatively, labelled cells demonstrate the greatest signal intensity loss and contrast on T2*-weighted images. Labelled cells can be detected in both synthetic and natural polymers, and can be distinguished from the native tissue environment of the rat IVD. Finally, labelling does not significantly impair cell viability. Consequently, this technique shows promise as a potential method for in vivo longitudinal tracking of stem cell based regeneration of the IVD. PMID:18677684

Saldanha, K J; Piper, S L; Ainslie, K M; Kim, H T; Majumdar, S

2008-01-01

243

The effect of postharvest calcium application in hydro-cooling water on tissue calcium content, biochemical changes, and quality attributes of sweet cherry fruit.  

PubMed

To improve storage/shipping quality of sweet cherry (Prunus avium L.), the effect of calcium chloride (CaCl2) added to hydro-cooling water on physiological and biochemical processes related to fruit and pedicel quality was investigated on two major cultivars. The fruit tissue Ca content increased up to 29-85% logarithmically for 'Sweetheart' and 39-188% linearly for 'Lapins' as CaCl2 rate increased from 0.2% to 2.0% at 0 °C for 5 min. The increase of fruit tissue Ca content was accompanied by reductions in respiration rate, ascorbic acid degradation, and membrane lipid peroxidation, which enhanced total phenolics content and total antioxidant capacity, and resulted in increases in fruit firmness and pitting resistance and decreases in titratable acidity loss and decay of both cultivars. Pedicel browning was inhibited by CaCl2 at 0.2% and 0.5%, but increased by higher rates at 1.0% and 2.0%, possibly via modifying membrane lipid peroxidation. PMID:24799204

Wang, Yan; Xie, Xingbin; Long, Lynn E

2014-10-01

244

Polarization dictates iron handling by inflammatory and alternatively activated macrophages  

PubMed Central

Background Macrophages play a key role in iron homeostasis. In peripheral tissues, they are known to polarize into classically activated (or M1) macrophages and alternatively activated (or M2) macrophages. Little is known on whether the polarization program influences the ability of macrophages to store or recycle iron and the molecular machinery involved in the processes. Design and Methods Inflammatory/M1 and alternatively activated/M2 macrophages were propagated in vitro from mouse bone-marrow precursors and polarized in the presence of recombinant interferon-? or interleukin-4. We characterized and compared their ability to handle radioactive iron, the characteristics of the intracellular iron pools and the expression of molecules involved in internalization, storage and export of the metal. Moreover we verified the influence of iron on the relative ability of polarized macrophages to activate antigen-specific T cells. Results M1 macrophages have low iron regulatory protein 1 and 2 binding activity, express high levels of ferritin H, low levels of transferrin receptor 1 and internalize – albeit with low efficiency -iron only when its extracellular concentration is high. In contrast, M2 macrophages have high iron regulatory protein binding activity, express low levels of ferritin H and high levels of transferrin receptor 1. M2 macrophages have a larger intracellular labile iron pool, effectively take up and spontaneously release iron at low concentrations and have limited storage ability. Iron export correlates with the expression of ferroportin, which is higher in M2 macrophages. M1 and M2 cells activate antigen-specific, MHC class II-restricted T cells. In the absence of the metal, only M1 macrophages are effective. Conclusions Cytokines that drive macrophage polarization ultimately control iron handling, leading to the differentiation of macrophages into a subset which has a relatively sealed intracellular iron content (M1) or into a subset endowed with the ability to recycle the metal (M2).

Corna, Gianfranca; Campana, Lara; Pignatti, Emanuele; Castiglioni, Alessandra; Tagliafico, Enrico; Bosurgi, Lidia; Campanella, Alessandro; Brunelli, Silvia; Manfredi, Angelo A.; Apostoli, Pietro; Silvestri, Laura; Camaschella, Clara; Rovere-Querini, Patrizia

2010-01-01

245

Increased Iron Sequestration in Alveolar Macrophages in Chronic Obtructive Pulmonary Disease  

PubMed Central

Free iron in lung can cause the generation of reactive oxygen species, an important factor in chronic obstructive pulmonary disease (COPD) pathogenesis. Iron accumulation has been implicated in oxidative stress in other diseases, such as Alzheimer’s and Parkinson’s diseases, but little is known about iron accumulation in COPD. We sought to determine if iron content and the expression of iron transport and/or storage genes in lung differ between controls and COPD subjects, and whether changes in these correlate with airway obstruction. Explanted lung tissue was obtained from transplant donors, GOLD 2–3 COPD subjects, and GOLD 4 lung transplant recipients, and bronchoalveolar lavage (BAL) cells were obtained from non-smokers, healthy smokers, and GOLD 1–3 COPD subjects. Iron-positive cells were quantified histologically, and the expression of iron uptake (transferrin and transferrin receptor), storage (ferritin) and export (ferroportin) genes was examined by real-time RT-PCR assay. Percentage of iron-positive cells and expression levels of iron metabolism genes were examined for correlations with airflow limitation indices (forced expiratory volume in the first second (FEV1) and the ratio between FEV1 and forced vital capacity (FEV1/FVC)). The alveolar macrophage was identified as the predominant iron-positive cell type in lung tissues. Futhermore, the quantity of iron deposit and the percentage of iron positive macrophages were increased with COPD and emphysema severity. The mRNA expression of iron uptake and storage genes transferrin and ferritin were significantly increased in GOLD 4 COPD lungs compared to donors (6.9 and 3.22 fold increase, respectively). In BAL cells, the mRNA expression of transferrin, transferrin receptor and ferritin correlated with airway obstruction. These results support activation of an iron sequestration mechanism by alveolar macrophages in COPD, which we postulate is a protective mechanism against iron induced oxidative stress.

Philippot, Quentin; Deslee, Gaetan; Adair-Kirk, Tracy L.; Woods, Jason C.; Byers, Derek; Conradi, Susan; Dury, Sandra; Perotin, Jeanne Marie; Lebargy, Francois; Cassan, Christelle; Le Naour, Richard; Holtzman, Michael J.; Pierce, Richard A.

2014-01-01

246

Influence of different dietary vitamin C levels on vitamin E and C content and oxidative stability in various tissues and stored m. longissimus dorsi of growing pigs.  

PubMed

Both vitamin E and C have antioxidative properties and may act synergistically. To examine a possible interaction between vitamin E, C and oxidative stability in various tissues, 40 barrows (25-105kg body weight) were allocated to four cereal-based diets (13.4MJ digestible energy/kg, 168g crude protein/kg, 140mg dietary dl-?-tocopheryl acetate) which were supplemented with 0 (B), 150 (C100), 300 (C200) or 600 (C400)mg/kg crystalline ascorbic acid. The influence of storage time on these factors in m. longissimus dorsi samples (LD) was investigated. Samples of liver (LI), heart (HT), spleen (SP), backfat outer layer (BF) and LD were obtained. Dry matter, vitamin E, vitamin C and thiobarbituric acid reactive substances (TBARS) were analyzed in all investigated tissues and in addition color (L(?), a(?), b(?) values) and drip loss measurements in LD at day 0, 1, 2, 3, 4 and 8 were collected. The treatments did not influence growth performance and slaughter data of the pigs. Neither the vitamin E nor the vitamin C content of investigated tissues showed differences due to feeding treatments. There was also a lack of response to the amount in TBARS. Parameters in LD samples were only affected by storage time and not by diets. The results show that dietary use of both vitamins simultaneously did not further improve qualitative characteristics of the investigated pork tissues. PMID:22062309

Gebert, S; Eichenberger, B; Pfirter, H P; Wenk, C

2006-06-01

247

Iron and ferritin accumulate in separate cellular locations in Phaseolus seeds  

PubMed Central

Background Iron is an important micronutrient for all living organisms. Almost 25% of the world population is affected by iron deficiency, a leading cause of anemia. In plants, iron deficiency leads to chlorosis and reduced yield. Both animals and plants may suffer from iron deficiency when their diet or environment lacks bioavailable iron. A sustainable way to reduce iron malnutrition in humans is to develop staple crops with increased content of bioavailable iron. Knowledge of where and how iron accumulates in seeds of crop plants will increase the understanding of plant iron metabolism and will assist in the production of staples with increased bioavailable iron. Results Here we reveal the distribution of iron in seeds of three Phaseolus species including thirteen genotypes of P. vulgaris, P. coccineus, and P. lunatus. We showed that high concentrations of iron accumulate in cells surrounding the provascular tissue of P. vulgaris and P. coccineus seeds. Using the Perls' Prussian blue method, we were able to detect iron in the cytoplasm of epidermal cells, cells near the epidermis, and cells surrounding the provascular tissue. In contrast, the protein ferritin that has been suggested as the major iron storage protein in legumes was only detected in the amyloplasts of the seed embryo. Using the non-destructive micro-PIXE (Particle Induced X-ray Emission) technique we show that the tissue in the proximity of the provascular bundles holds up to 500 ?g g-1 of iron, depending on the genotype. In contrast to P. vulgaris and P. coccineus, we did not observe iron accumulation in the cells surrounding the provascular tissues of P. lunatus cotyledons. A novel iron-rich genotype, NUA35, with a high concentration of iron both in the seed coat and cotyledons was bred from a cross between an Andean and a Mesoamerican genotype. Conclusions The presented results emphasize the importance of complementing research in model organisms with analysis in crop plants and they suggest that iron distribution criteria should be integrated into selection strategies for bean biofortification.

2010-01-01

248

Serum and liver iron differently regulate the bone morphogenetic protein 6 (BMP6)-SMAD signaling pathway in mice  

PubMed Central

The bone morphogenetic protein 6 (BMP6)-SMAD signaling pathway is a central regulator of hepcidin expression and systemic iron balance. However, the molecular mechanisms by which iron is sensed to regulate BMP6-SMAD signaling and hepcidin expression are unknown. Here, we examined the effects of circulating and tissue iron on Bmp6-Smad pathway activation and hepcidin expression in vivo after acute and chronic enteral iron administration in mice. We demonstrated that both transferrin saturation and liver iron content independently influence hepcidin expression. While liver iron content is independently positively correlated with hepatic Bmp6 mRNA expression and overall activation of the Smad1/5/8 signaling pathway, transferrin saturation activates the downstream Smad1/5/8 signaling cascade, but does not induce Bmp6 mRNA expression in the liver. Hepatic inhibitory Smad7 mRNA expression is increased by both acute and chronic iron administration and mirrors overall activation of the Smad1/5/8 signaling cascade. In contrast to the Smad pathway, the extracellular signal-regulated kinase 1 and 2 (Erk1/2) mitogen-activated protein kinase (Mapk) signaling pathway in the liver is not activated by acute or chronic iron administration in mice. Conclusion Our data demonstrate that the hepatic Bmp6-Smad signaling pathway is differentially activated by circulating and tissue iron to induce hepcidin expression, while the hepatic Erk1/2 signaling pathway is not activated by iron in vivo.

Corradini, Elena; Meynard, Delphine; Wu, Qifang; Chen, Shan; Ventura, Paolo; Pietrangelo, Antonello; Babitt, Jodie L.

2011-01-01

249

Iron economy in Chlamydomonas reinhardtii  

PubMed Central

While research on iron nutrition in plants has largely focused on iron-uptake pathways, photosynthetic microbes such as the unicellular green alga Chlamydomonas reinhardtii provide excellent experimental systems for understanding iron metabolism at the subcellular level. Several paradigms in iron homeostasis have been established in this alga, including photosystem remodeling in the chloroplast and preferential retention of some pathways and key iron-dependent proteins in response to suboptimal iron supply. This review presents our current understanding of iron homeostasis in Chlamydomonas, with specific attention on characterized responses to changes in iron supply, like iron-deficiency. An overview of frequently used methods for the investigation of iron-responsive gene expression, physiology and metabolism is also provided, including preparation of media, the effect of cell size, cell density and strain choice on quantitative measurements and methods for the determination of metal content and assessing the effect of iron supply on photosynthetic performance.

Glaesener, Anne G.; Merchant, Sabeeha S.; Blaby-Haas, Crysten E.

2013-01-01

250

MRI measures of corpus callosum iron and myelin in early Huntington's disease.  

PubMed

Increased iron in subcortical gray matter (GM) structures of patients with Huntington's disease (HD) has been suggested as a causal factor in neuronal degeneration. But how iron content is related to white matter (WM) changes in HD is still unknown. For example, it is not clear whether WM changes share the same physiopathology (i.e. iron accumulation) with GM or whether there is a different mechanism. The present study used MRI to examine iron content in premanifest gene carriers (PreHD, n = 25) and in early HD patients (n = 25) compared with healthy controls (n = 50). 3T MRI acquisitions included high resolution 3D T1, EPI sequences for diffusion tensor imaging (DTI) as an indirect measure of tissue integrity, and T2*-weighted gradient echo-planar imaging for MR-based relaxometry (R2*), which provides an indirect measure of ferritin/iron deposition in the brain. Myelin breakdown starts in the PreHD stage, but there is no difference in iron content values. Iron content reduction manifests later, in the early HD stage, in which we found a lower R2* parameter value in the isthmus. The WM iron reduction in HD is temporally well-defined (no iron differences in PreHD subjects and iron differences only in early HD patients). Iron level in callosal WM may be regarded as a marker of disease state, as iron does not differentiate PreHD subjects from controls but distinguishes between PreHD and HD. Hum Brain Mapp 35:3143-3151, 2014. © 2013 Wiley Periodicals, Inc. PMID:24895252

Di Paola, M; Phillips, O R; Sanchez-Castaneda, C; Di Pardo, A; Maglione, V; Caltagirone, C; Sabatini, U; Squitieri, F

2014-07-01

251

Distribution and accumulation of Cy5.5-labeled thermally cross-linked superparamagnetic iron oxide nanoparticles in the tissues of ICR mice  

PubMed Central

Free Cy5.5 dye and Cy5.5-labeled thermally cross-linked superparamagnetic iron oxide nanoparticles (TCL-SPION) have been routinely used for in vivo optical imaging. However, there is little information about the distribution and accumulation of free Cy5.5 dye and Cy5.5-labeled TCL-SPION in the tissues of mice. Free Cy5.5 dye (0.1 mg/kg body weight) and Cy5.5-labeled TCL-SPION (15 mg/kg body weight) were intravenously injected into the tail vein of ICR mice. The biodistribution and accumulation of the TCL-SPION and Cy5.5 were observed by ex vivo optical imaging and fluorescence signal generation at various time points over 28 days. Cy5.5 dye fluorescence in various organs was rapidly eliminated from 0.5 to 24 h post-injection. Fluorescence intensity of Cy5.5 dye in the liver, lung, kidney, and stomach was fairly strong at the early time points within 1 day post-injection. Cy5.5-labeled TCL-SPION had the highest fluorescence density in the lung at 0.5 h post-injection and decreased rapidly over time. Fluorescence density in liver and spleen was maintained over 28 days. These results suggest that TCL-SPION can be useful as a carrier of therapeutic reagents to treat diseases by persisting for long periods of time in the body.

Hue, Jin Joo; Lee, Hu-Jang; Jon, Sangyong; Nam, Sang Yoon; Yun, Young Won; Kim, Jong-Soo

2013-01-01

252

Variations in T2* and Fat Content of Murine Brown and White Adipose Tissues by Chemical-Shift MRI  

PubMed Central

Purpose To compare T2* relaxation times and proton density fat-fraction (PDFF) values between brown (BAT) and white (WAT) adipose tissue in lean and ob/ob mice. Materials and Methods A group of lean male mice (n=6), and two groups of ob/ob male mice placed on similar four-week (n=6) and eight-week (n=8) ad libitum diets, were utilized. The animals were imaged at 3 Tesla using a T2*-corrected chemical-shift based water-fat MRI method that provides simultaneous estimation of T2* and PDFF on a voxel-wise basis. Regions of interest were drawn within the interscapular BAT and gonadal WAT depots on co-registered T2* and PDFF maps. Measurements were assessed using analysis of variance, Bonferroni-adjusted t-test for multi-group comparisons, and the Tukey post-hoc test. Results Significant differences (p<0.01) in BAT T2* and PDFF were observed between the lean and ob/ob groups. The ob/ob animals exhibited longer BAT T2* and greater PDFF than lean animals. However, only BAT PDFF was significantly different (p<0.01) between the two ob/ob groups. When comparing BAT to WAT within each group, T2* and PDFF values were consistently lower in BAT than WAT (p<0.01). The difference was most prominent in the lean animals. In both ob/ob groups, BAT exhibited very WAT-like appearances and properties on the MRI images. Conclusion T2* and PDFF are lower in BAT than WAT. This is likely due to variations in tissue composition. The values were consistently lower in lean mice than in ob/ob mice, suggestive of the former’s greater demand for BAT thermogenesis and reflective of leptin hormone deficiencies and diminished BAT metabolic activity in the latter.

Hu, Houchun H.; Hines, Catherine D.G.; Smith, Daniel L.; Reeder, Scott B.

2011-01-01

253

Measurement of colloidal iron binding at low pH in cartilage using the proton microprobe.  

PubMed

Quantitative micro-PIXE analysis was performed on mouse embryo epiphyseal cartilage and on the rib cartilage of mature animals after incubation of sections with colloidal iron at pH 1.8. The iron content as well as that of sulphur and phosphorus and Fe/S, Fe/P ratios were determined. It was found that colloidal iron content was higher in the cartilage than in other tissues. The cartilage also displayed the highest content of sulphur. The Fe/S ratio was however not constant, being highest in the degeneration zone close to the mineralization front, where the binding of iron was strongest while the amount of sulphur decreased. This indicates that factors other than number of sulphate groups influence the binding of positively charged molecules to glycosaminoglycans. This is confirmed by differences in the results obtained for embryonic and mature rib cartilage. PMID:2974842

Cichocki, T; Gonsior, B; Höfert, M; Jarczyk, L; Rokita, E; Strzalkowski, A; Sych, M

1988-04-01

254

Parathyroid hormone PTH(1-34) increases the volume, mineral content, and mechanical properties of regenerated mineralizing tissue after distraction osteogenesis in rabbits  

PubMed Central

Background and purpose Parathyroid hormone (PTH) has attracted considerable interest as a bone anabolic agent. Recently, it has been suggested that PTH can also enhance bone repair after fracture and distraction osteogenesis. We analyzed bone density and strength of the newly regenerated mineralized tissue after intermittent treatment with PTH in rabbits, which undergo Haversian bone remodeling similar to that in humans. Methods 72 New Zealand White rabbits underwent tibial mid-diaphyseal osteotomy and the callus was distracted 1 mm/day for 10 days. The rabbits were divided into 3 groups, which received injections of PTH 25 µg/kg/day for 30 days, saline for 10 days and PTH 25 µg/kg/day for 20 days, or saline for 30 days. At the end of the study, the rabbits were killed and the bone density was evaluated with DEXA. The mechanical bone strength was determined by use of a 3-point bending test. Results In the 2 PTH-treated groups the regenerate callus ultimate load was 33% and 30% higher, absorbed energy was 100% and 65% higher, BMC was 61% and 60% higher, and callus tissue volume was 179% and 197% higher than for the control group. Interpretation We found that treatment with PTH during distraction osteogenesis resulted in substantially higher mineralized tissue volume, mineral content, and bending strength. This suggests that treatment with PTH may benefit new bone formation during distraction osteogenesis and could form a basis for clinical application of this therapy in humans.

2009-01-01

255

Synthesis of novel magnetic iron metal silica (Fe SBA15) and magnetite silica (Fe3O4 SBA15) nanocomposites with a high iron content using temperature-programed reduction  

Microsoft Academic Search

Magnetic iron metal-silica and magnetite-silica nanocomposites have been prepared via temperature-programed reduction (TPR) of an iron oxide-SBA-15 (SBA: Santa Barbara Amorphous) composite. TPR of the starting SBA-15 supported Fe2O3 generated Fe3O4 and FeO as stepwise intermediates in the ultimate formation of Fe-SBA-15. The composite materials have been characterized by means of x-ray diffraction, high resolution transmission electron microscopy and SQUID

H. H. P. Yiu; M. A. Keane; Z. A. D. Lethbridge; M. R. Lees; A. J. El Haj; J. Dobson

2008-01-01

256

Synthesis of novel magnetic iron metal–silica (Fe–SBA15) and magnetite–silica (Fe3O4–SBA15) nanocomposites with a high iron content using temperature-programed reduction  

Microsoft Academic Search

Magnetic iron metal–silica and magnetite–silica nanocomposites have been prepared via temperature-programed reduction (TPR) of an iron oxide–SBA-15 (SBA: Santa Barbara Amorphous) composite. TPR of the starting SBA-15 supported Fe2O3 generated Fe3O4 and FeO as stepwise intermediates in the ultimate formation of Fe–SBA-15. The composite materials have been characterized by means of x-ray diffraction, high resolution transmission electron microscopy and SQUID

H H P Yiu; M A Keane; Z A D Lethbridge; M R Lees; A J El Haj; J Dobson

2008-01-01

257

Ferritin: the protein nanocage and iron biomineral in health and in disease.  

PubMed

At the center of iron and oxidant metabolism is the ferritin superfamily: protein cages with Fe(2+) ion channels and two catalytic Fe/O redox centers that initiate the formation of caged Fe2O3·H2O. Ferritin nanominerals, initiated within the protein cage, grow inside the cage cavity (5 or 8 nm in diameter). Ferritins contribute to normal iron flow, maintenance of iron concentrates for iron cofactor syntheses, sequestration of iron from invading pathogens, oxidant protection, oxidative stress recovery, and, in diseases where iron accumulates excessively, iron chelation strategies. In eukaryotic ferritins, biomineral order/crystallinity is influenced by nucleation channels between active sites and the mineral growth cavity. Animal ferritin cages contain, uniquely, mixtures of catalytically active (H) and inactive (L) polypeptide subunits with varied rates of Fe(2+)/O2 catalysis and mineral crystallinity. The relatively low mineral order in liver ferritin, for example, coincides with a high percentage of L subunits and, thus, a low percentage of catalytic sites and nucleation channels. Low mineral order facilitates rapid iron turnover and the physiological role of liver ferritin as a general iron source for other tissues. Here, current concepts of ferritin structure/function/genetic regulation are discussed and related to possible therapeutic targets such as mini-ferritin/Dps protein active sites (selective pathogen inhibition in infection), nanocage pores (iron chelation in therapeutic hypertransfusion), mRNA noncoding, IRE riboregulator (normalizing the ferritin iron content after therapeutic hypertransfusion), and protein nanovessels to deliver medicinal or sensor cargo. PMID:24102308

Theil, Elizabeth C

2013-11-01

258

The effect of immobilization and 3 (beta-aminoethyl)-1, 2, 4 triazol on the calcium content in gastric tissues of guinea pigs during the formation of experimental ulcers  

NASA Technical Reports Server (NTRS)

A sharp fall in the concentration of calcium in gastric tissues upon immobilization and after administration of the histamine analog was recorded. Similar shifts were seen to occur in the blood plasma as well. This implies that under the effect of different action, tissue dystrophy develops by following a common mechanism involving not only the adenyl cyclase system, but that of calcium ion metabolism as well. The calcium ion content in the blood plasma and gastric tissues were measured by atomic absorption spectrophotometry.

Grechishkin, L. L.; Ritling, K.

1980-01-01

259

Detection of verocytotoxin-producing Escherichia coli serogroups 0157 and 026 in the cecal content and lymphatic tissue of cattle at slaughter in Italy.  

PubMed

Verocytotoxin-producing Escherichia coli (VTEC) has emerged as a foodborne pathogen that can cause severe and potentially fatal illnesses, such as hemorrhagic colitis or the hemolytic uremic syndrome. In this study, 182 cattle at slaughter (119 dairy cows and 63 feedlot cattle) were randomly selected and tested for the presence of VTEC serogroups O26, O103, O111, O145, and O157 in their cecal content and lymphatic tissue (tonsils or mesenteric lymph nodes). A total of 364 samples were evaluated with an immunomagnetic separation technique followed by slide agglutination. Presumptive VTEC 026, O103, O111, O145, and O157 isolates were tested by Vero cell assay for verocytotoxin production and by multiplex PCR assay for the detection of vtxl, vtx2, eae, and E-hlyA genes. VTEC O157 was detected in 6 (3.3%) of 182 animals, and VTEC 026 was detected in 1 (0.5%) of 182 animals. No VTEC O103, VTEC O111, or VTEC O145 isolates were found in cattle feces, but one VTEC O91:H- vtx2+, eae-, E-hlyA+ strain nonspecifically cross-reacted with the VTEC O103 type. The prevalence of VTEC O157 in the lymphatic tissue of cattle was 1.1% in both tonsils (1 of 93 samples) and mesenteric lymph nodes (1 of 89 samples). Lymphatic tissue contamination was observed only in VTEC O157 intestinal carriers; two (33.3%) of six fecal carriers were simultaneously VTEC O157 lymphatic carriers. This finding suggests that VTEC O157 contamination of meat does not necessarily come from feces or the environment. No other VTEC serogroups were detected in the lymphatic tissue of slaughtered cattle. PMID:17612082

Bonardi, Silvia; Foni, Emanuela; Chiapponi, Chiara; Salsi, Alessandra; Brindani, Franco

2007-06-01

260

Dietary amylose and amylopectin ratio and resistant starch content affects plasma glucose, lactic acid, hormone levels and protein synthesis in splanchnic tissues.  

PubMed

Experiments were conducted to determine the effects of feeding different starch sources on piglets. Four diets were formulated with maize, brown rice, sticky rice and Hi-Maize 1043 as starch sources, with resistant starch (RS) contents of 2.3%, 0.9%, 0.0%, 20.6%, and amylose and amylopectin ratio of 0.23%, 0.21%, 0.18%, 0.06% respectively. Fifty-six pigs weaned at 28 days of age were randomly assigned to one of the four diets. In Exp. 1, six piglets in each group were fitted with an indwelling jugular catheter. After 25 days of feeding trial, venous blood samples were obtained at time zero and every 1 h for 4 h. In Exp. 2, the remaining piglets were used to determine the effects of different starch sources on the fractional synthesis rate (FSR). The results indicated that feeding the Hi-Maize 1043 diet decreased (p < 0.05) plasma contents of glucose, insulin, lactic acid and T(3), while sticky rice increased plasma contents of glucose and insulin. The insulin contents in piglets fed the sticky rice diet was 69.2 microIU/ml at 1 h post-feeding which was highest among the starch diets. The FSR in the pancreas, spleen, duodenum, jejunum, ileum and colon in the corn group were much higher (p < 0.05) than that in the sticky rice group. These results suggest that RS is potentially beneficial for improving insulin sensitivity in young pigs and that the ratio of amylose and amylopectin have significantly effects on the FSR in splanchnic tissues in weaned piglets. Another finding of this study indicated maize with a ratio of amylose and amylopectin of 0.23 has the best starch sources for pig production. PMID:19175452

Deng, J; Wu, X; Bin, S; Li, T-J; Huang, R; Liu, Z; Liu, Y; Ruan, Z; Deng, Z; Hou, Y; Yin, Y-L

2010-04-01

261

Estimates of dry and wet deposition using tissue N contents and 15N natural abundance in epilithic mosses in atmospheric NHy-dominated areas  

NASA Astrophysics Data System (ADS)

Measurement of dry N deposition by physical methods is time-consuming because it is usually difficult to measure directly. In this study, an alternative approach has successfully been proposed by coupling isotopic ratios with tissue N contents of epilithic mosses. The method is to use moss N contents to quantitatively estimate total N (TN) deposition and then to use 15N natural abundance in mosses to discriminate dry and wet deposition in atmospheric NHy-dominated areas (NHy/TN > 0.75). On the basis of the isotopic balance between atmospheric NHy and moss tissue N and the correlation between atmospheric NHy concentrations and their isotopes, both wet and dry N deposition can be estimated. By the approach, we have estimated rainwater ammonium concentrations and contribution percentage of wet deposition to total N deposition (fwet) in some areas of southern China. The results indicated that rainwater ammonium concentrations increased relative to those reported previously in most cities, owing to stronger anthropogenic activity. The fwet values estimated in most sites were found to be slightly higher than those reported, because faster transformation rates due to higher SO2 emission later in acid rain areas of southern China favored deposition in the form of wet deposition instead of dry deposition. The largest uncertainty of the approach comes from the influence of NOx in the atmosphere, and thus it cannot be used in areas where NOx deposition is high. The presented isotopic approach represents a new application of moss biomonitoring for estimating atmospheric N deposition in NHy-dominated areas.

Xiao, Hua-Yun; Liu, Cong-Qiang

2011-02-01

262

Iron supplementation improves progressive fatigue resistance during dynamic knee extensor exercise in iron-depleted  

Microsoft Academic Search

Background: Tissue iron depletion may negatively affect endurance performance and muscle fatigability. Objective: We investigated tissue-level iron depletion and pro- gressive fatigue of the quadriceps during dynamic knee-extension exercise in young women. Design: Twenty iron-depleted (serum ferritin < 20 ? g\\/L), nonane- mic (hemoglobin > 110 g\\/L) women (x - ± SEM age: 29.1 ± 1.2 y) received iron (iron

Tom D Brutsaert; Sonia Hernandez-Cordero; Juan Rivera; Tracey Viola; Gail Hughes; Jere D Haas

263

Iron homeostasis in the liver  

PubMed Central

Iron is an essential nutrient that is tightly regulated. A principal function of the liver is the regulation of iron homeostasis. The liver senses changes in systemic iron requirements and can regulate iron concentrations in a robust and rapid manner. The last 10 years have led to the discovery of several regulatory mechanisms in the liver which control the production of iron regulatory genes, storage capacity, and iron mobilization. Dysregulation of these functions leads to an imbalance of iron, which is the primary causes of iron-related disorders. Anemia and iron overload are two of the most prevalent disorders worldwide and affect over a billion people. Several mutations in liver-derived genes have been identified, demonstrating the central role of the liver in iron homeostasis. During conditions of excess iron, the liver increases iron storage and protects other tissues, namely the heart and pancreas from iron-induced cellular damage. However, a chronic increase in liver iron stores results in excess reactive oxygen species production and liver injury. Excess liver iron is one of the major mechanisms leading to increased steatohepatitis, fibrosis, cirrhosis, and hepatocellular carcinoma.

Anderson, Erik R; Shah, Yatrik M

2014-01-01

264

Expression profile of small RNAs in Acacia mangium secondary xylem tissue with contrasting lignin content - potential regulatory sequences in monolignol biosynthetic pathway  

PubMed Central

Background Lignin, after cellulose, is the second most abundant biopolymer accounting for approximately 15-35% of the dry weight of wood. As an important component during wood formation, lignin is indispensable for plant structure and defense. However, it is an undesirable component in the pulp and paper industry. Removal of lignin from cellulose is costly and environmentally hazardous process. Tremendous efforts have been devoted to understand the role of enzymes and genes in controlling the amount and composition of lignin to be deposited in the cell wall. However, studies on the impact of downregulation and overexpression of monolignol biosynthesis genes in model species on lignin content, plant fitness and viability have been inconsistent. Recently, non-coding RNAs have been discovered to play an important role in regulating the entire monolignol biosynthesis pathway. As small RNAs have critical functions in various biological process during wood formation, small RNA profiling is an important tool for the identification of complete set of differentially expressed small RNAs between low lignin and high lignin secondary xylem. Results In line with this, we have generated two small RNAs libraries from samples with contrasting lignin content using Illumina GAII sequencer. About 10 million sequence reads were obtained in secondary xylem of Am48 with high lignin content (41%) and a corresponding 14 million sequence reads were obtained in secondary xylem of Am54 with low lignin content (21%). Our results suggested that A. mangium small RNAs are composed of a set of 12 highly conserved miRNAs families found in plant miRNAs database, 82 novel miRNAs and a large proportion of non-conserved small RNAs with low expression levels. The predicted target genes of those differentially expressed conserved and non-conserved miRNAs include transcription factors associated with regulation of the lignin biosynthetic pathway genes. Some of these small RNAs play an important role in epigenetic silencing. Differential expression of the small RNAs between secondary xylem tissues with contrasting lignin content suggests that a cascade of miRNAs play an interconnected role in regulating the lignin biosynthetic pathway in Acacia species. Conclusions Our study critically demonstrated the roles of small RNAs during secondary wall formation. Comparison of the expression pattern of small RNAs between secondary xylem tissues with contrasting lignin content strongly indicated that small RNAs play a key regulatory role during lignin biosynthesis. Our analyses suggest an evolutionary mechanism for miRNA targets on the basis of the length of their 5’ and 3’ UTRs and their cellular roles. The results obtained can be used to better understand the roles of small RNAs during lignin biosynthesis and for the development of gene constructs for silencing of specific genes involved in monolignol biosynthesis with minimal effect on plant fitness and viability. For the first time, small RNAs were proven to play an important regulatory role during lignin biosynthesis in A. mangium.

2011-01-01

265

Valve proteoglycan content and glycosaminoglycan fine structure are unique to microstructure, mechanical load and age: Relevance to an age-specific tissue-engineered heart valve.  

PubMed

This study characterized valve proteoglycan and glycosaminoglycan composition during development and aging. This knowledge is important for the development of age-specific tissue-engineered heart valves as well as treatments for age-specific valvulopathies. Aortic valves and mitral valves from first-third trimester, 6-week, 6-month and 6-year-old pigs were examined using immunohistochemistry for versican, biglycan, decorin and hyaluronan, as well as elastin and fibrillin. The fine structure of glycosaminoglycans was examined by fluorophore-assisted carbohydrate electrophoresis. Decorin expression was strongest in the 6-year-old valves, particularly in the aortic valve spongiosa. The quantity of iduronate was also highest in the 6-year-old valves. The central tensile-loading region of the anterior mitral leaflet demonstrated reduced glycosaminoglycan content, chain length and hydration and a larger fraction of 4-sulfated iduronate and lower fraction of 6-sulfation. With age, the anterior leaflet center showed a further increase in 4-sulfated iduronate and decrease in 6-sulfation. In contrast, the anterior leaflet free edge showed decreased iduronate and 4-sulfated glucuronate content with age. The young aortic valve was similar to the mitral valve free edge with a higher concentration of glycosaminoglycans and 6-rather than 4-sulfation, but aged to resemble the mitral anterior leaflet center, with an increase in 4-sulfated iduronate content and a decrease in the 6-sulfation fraction. Elastin and fibrillin often co-localized with the proteoglycans studied, but elastin co-localized most specifically with versican. In conclusion, composition and fine structure changes in valve proteoglycans and glycosaminoglycans with age are complex and distinct within valve type, histological layers and regions of different mechanical loading. PMID:18448399

Stephens, Elizabeth H; Chu, Chia-Kai; Grande-Allen, K Jane

2008-09-01

266

Effects of dietary fat source and breed on the carcass composition, n-3 polyunsaturated fatty acid and conjugated linoleic acid content of sheep meat and adipose tissue.  

PubMed

Seventy-two 8-week-old ram lambs from three breeds, Suffolk, Soay and Friesland, were offered one of four diets based on dried grass and formulated to have a similar fatty acid content (60 g/kg DM) and containing: Megalac (high in 16 : 0, control; Volac Ltd, Royston, Herts., UK), whole linseed (18 : 3n-3), fish oil (20 : 5n-3 and 22 : 6n-3) or whole linseed plus fish oil. The lambs were slaughtered at approximately half of their mature live weight (43, 21 and 43 kg for Suffolk, Soay and Friesland lambs, respectively). Fish oil reduced DM intake and lamb live-weight gain (P<0.001), while DM intake, live-weight gain and subcutaneous fat content were highest in Suffolk and lowest in Soay lambs. Linseed feeding doubled the proportion (x100) of 18 : 3n-3 in the longissimus dorsi from 1.4 to 3.1 and in the subcutaneous adipose tissue from 1.2 to 2.6 (P<0.001). Suffolk and particularly Soay lambs contained higher proportions of 18 : 3n-3 than Friesland lambs in the longissimus dorsi, while in the adipose tissue, Suffolk lambs had the highest level. Feeding fish oil increased the muscle proportion (x100) of 20 : 5n-3 from 0.7 to 2.3 and 22 : 6n-3 from 0.3 to 0.8 (P<0.001). By contrast, the proportions of the longer-chain n-3 polyunsaturated fatty acids were similar across all three breeds. All three lipid supplements containing n-3 polyunsaturated fatty acids increased the content of muscle trans-18 : 1 relative to the control values, but conjugated linoleic acid (cis-9,trans-11-18 : 2) only increased in the muscle of lambs fed linseed. Feeding linseed or fish oil lowered the n-6 : n-3 ratio in sheep meat, but neither diet nor breed had much effect on the polyunsaturated fatty acid: saturated fatty acid ratio. PMID:12493092

Wachira, A M; Sinclair, L A; Wilkinson, R G; Enser, M; Wood, J D; Fisher, A V

2002-12-01

267

Mimicking Liver Iron Overload Using Liposomal Ferritin Preparations  

PubMed Central

Close monitoring of liver iron content is necessary to prevent iron overload in transfusion-dependent anemias. Liver biopsy remains the gold standard; however, MRI potentially offers a noninvasive alternative. Iron metabolism and storage is complicated and tissue/disease-specific. This report demonstrates that iron distribution may be more important than iron speciation with respect to MRI signal changes. Simple synthetic analogs of hepatic lysosomes were constructed from noncovalent attachment of horse-spleen ferritin to 0.4 ?m diameter phospholipid liposomes suspended in agarose. Graded iron loading was achieved by varying ferritin burden per liposome as well as liposomal volume fraction. T1 and T2 relaxation times were measured on a 60 MHz NMR spectrometer and compared to simple ferritin-gel combinations. Liposomal-ferritin had 6-fold stronger T2 relaxivity than unaggregated ferritin but identical T1 relaxivity. Liposomal-ferritin T2 relaxivity also more closely matched published results from hemosiderotic marmoset liver, suggesting a potential role as an iron-calibration phantom.

Wood, John C.; Fassler, Joe D.; Meade, Tom

2010-01-01

268

The roles of iron in health and disease  

Microsoft Academic Search

Iron is vital for almost all living organisms by participating in a wide variety of metabolic processes, including oxygen transport, DNA synthesis, and electron transport. However, iron concentrations in body tissues must be tightly regulated because excessive iron leads to tissue damage, as a result of formation of free radicals. Disorders of iron metabolism are among the most common diseases

Pauline T. Lieu; Marja Heiskala; Per A. Peterson; Young Yang

2001-01-01

269

A gradual increase of iron toward the medial-inferior tip of the subthalamic nucleus.  

PubMed

The subthalamic nucleus (STN) is an important node of the cortico-basal ganglia network and the main target of deep brain stimulation (DBS) in Parkinson's disease. Histological studies have revealed an inhomogeneous iron distribution within the STN, which has been related to putative subdivisions within this nucleus. Here, we investigate the iron distribution in more detail using quantitative susceptibility mapping (QSM), a novel magnetic resonance imaging (MRI) contrast mechanism. QSM allows for detailed assessment of iron content in both in vivo and postmortem tissue. Twelve human participants and 7 postmortem brain samples containing the STN were scanned using ultra-high field 7 Tesla (T) MRI. Iron concentrations were found to be higher in the medial-inferior tip of the STN. Using quantitative methods we show that the increase of iron concentration towards the medial-inferior tip is of a gradual rather than a discrete nature. Hum Brain Mapp 35:4440-4449, 2014. © 2014 Wiley Periodicals, Inc. PMID:24596026

de Hollander, Gilles; Keuken, Max C; Bazin, Pierre-Louis; Weiss, Marcel; Neumann, Jane; Reimann, Katja; Wähnert, Miriam; Turner, Robert; Forstmann, Birte U; Schäfer, Andreas

2014-09-01

270

Iron Absorption in Drosophila melanogaster  

PubMed Central

The way in which Drosophila melanogaster acquires iron from the diet remains poorly understood despite iron absorption being of vital significance for larval growth. To describe the process of organismal iron absorption, consideration needs to be given to cellular iron import, storage, export and how intestinal epithelial cells sense and respond to iron availability. Here we review studies on the Divalent Metal Transporter-1 homolog Malvolio (iron import), the recent discovery that Multicopper Oxidase-1 has ferroxidase activity (iron export) and the role of ferritin in the process of iron acquisition (iron storage). We also describe what is known about iron regulation in insect cells. We then draw upon knowledge from mammalian iron homeostasis to identify candidate genes in flies. Questions arise from the lack of conservation in Drosophila for key mammalian players, such as ferroportin, hepcidin and all the components of the hemochromatosis-related pathway. Drosophila and other insects also lack erythropoiesis. Thus, systemic iron regulation is likely to be conveyed by different signaling pathways and tissue requirements. The significance of regulating intestinal iron uptake is inferred from reports linking Drosophila developmental, immune, heat-shock and behavioral responses to iron sequestration.

Mandilaras, Konstantinos; Pathmanathan, Tharse; Missirlis, Fanis

2013-01-01

271

Ovine uterine space restriction alters placental transferrin receptor and fetal iron status during late pregnancy  

PubMed Central

Background Fetal growth restriction is reported to be associated with impaired placental iron transport. Transferrin receptor (TfR) is a major placental iron transporter in humans, but is unstudied in sheep. TfR is regulated by both iron and nitric oxide (NO), the molecule produced by endothelial NOS (eNOS). We hypothesized that limited placental development downregulates both placental TfR and eNOS expression, thereby lowering fetal tissue iron. Methods An ovine surgical uterine space restriction (USR) model, combined with multifetal gestation, tested the extremes of uterine and placental adaptation. Blood, tissues, and placentomes from non-space restricted (NSR) singletons were compared to USR fetuses at 120 or 130 days of gestation (GD). Results When expressed proportionate to fetal weight, liver iron content did not differ while renal iron was higher in USR vs. NSR fetuses. Renal TfR protein expression did not differ, but placental TfR expression was lower in USR fetuses at GD130. Placental levels of TfR correlated to eNOS. TfR was localized throughout the placentome, including the hemophagous zone, implicating a role for TfR in ovine placental iron transport. Conclusion In conclusion, fetal iron was regulated in an organ-specific fashion. In USR fetuses, NO-mediated placental adaptations may prevent the normal upregulation of placental TfR at GD130.

Sun, Mary Y.; Habeck, Jason M.; Meyer, Katie M.; Koch, Jill M.; Ramadoss, Jayanth; Blohowiak, Sharon E.; Magness, Ronald R.; Kling, Pamela J.

2013-01-01

272

Iron deficiency: beyond anemia.  

PubMed

Iron deficiency is the most common nutritional disorder affecting at least one third of world's population. Though anemia is common manifestation of iron deficiency, other effects of iron deficiency on various tissues, organs and systems are usually under recognized. Impaired brain development and cognitive, behavioural and psychomotor impairment are most worrisome manifestations of iron deficiency. Studies have demonstrated that some of these changes occurring during period of brain growth spurt (<2 years age) may be irreversible. Association of iron deficiency with febrile seizures, pica, breath holding spells, restless leg syndrome and thrombosis is increasingly being recognized. Impaired cell-mediated immunity and bactericidal function are generally noted in iron-deficient persons; however, the findings are inconsistent. Despite proven reversible functional immunological defects in vitro studies, a clinically important relationship between states of iron deficiency and susceptibility to infections remains controversial. Studies from malaria endemic regions have reported increased incidence of malaria in association with iron supplementation. These and some other aspects of iron deficiency are reviewed in this article. PMID:20814842

Yadav, Dinesh; Chandra, Jagdish

2011-01-01

273

FT-IR study of the effect of lead and the influence of chelating agents, DMSA and D-Penicillamine, on the biochemical contents of brain tissues of Catla catla fingerlings  

Microsoft Academic Search

.  The goal of this study was to investigate the effect of lead and the influence of chelating agents,meso 2, 3-dimercaptosuccinic acid (DMSA) and D-Penicillamine, on the biochemical contents of the brain tissues of Catla catla fingerlings by Fourier Transform Infrared Spectroscopy. FT-IR spectra revealed significant differences in absorbance intensities\\u000a between control and lead-intoxicated brain tissues, reflecting a change in protein

P. L. R. M. Palaniappan; N. Krishnakumar; M. Vadivelu

2008-01-01

274

Iron studies in hemophilia  

SciTech Connect

Although iron deficiency is not recognized as a usual complication of hemophilia, we questioned whether intermittent occult loss of blood in urine or stool might predispose hemophiliacs to chronic iron deficiency. Seven men with factor VII and one with factor IX deficiency were studied. Blood studied, bone marrow aspirates, urine and stool samples, and ferrokinetics with total-body counting up to five months were examined. These data showed no excessive loss of blood during the study period; however, marrow iron stores were decidedly decreased, being absent in four subjects. We suggest that in some hemophiliacs, iron deposits in tissues such as synovial membranes may form a high proportion of the body's total iron stores.

Lottenberg, R.; Kitchens, C.S.; Roessler, G.S.; Noyes, W.D.

1981-12-01

275

Effect of molybdenum and chromium contents in sliding wear of high-chromium white cast iron: The relationship between microstructure and wear  

Microsoft Academic Search

High-chromium white cast irons are commonly used in applications requiring excellent abrasion resistance, as in the mining and mineral ore processing industry. Their excellent abrasion resistance is mainly due to their solidification microstructures. During their solidification, high levels of chromium (16–32%) lead to the formation of a high-volume fraction of eutectic M7C3-carbides, which may or may not be associated with

C. Scandian; C. Boher; J. D. B. de Mello; F. Rézaï-Aria

2009-01-01

276

The rolling\\/sliding wear response of conventionally processed and spray formed high chromium content cast iron at ambient and elevated temperature  

Microsoft Academic Search

The effect of spray forming on the wear properties of a 17% Cr 2.5% C white cast iron is described and compared with conventionally cast material of the same composition. Spray forming resulted in a substantial reduction in microstructural scale (eutectic (Cr,Fe)7C3 fields of up to 500 ?m in conventionally cast material were replaced by discrete carbides of typically 2–8

D. N. Hanlon; W. M. Rainforth; C. M. Sellars

1999-01-01

277

The effect of tumor CEA content and tumor size on tissue uptake of indium 111-labeled anti-CEA monoclonal antibody.  

PubMed

This study was undertaken to determine the effect of tumor size and tumor carcinoembryonic antigen (CEA) content on the uptake of indium 111 (111In)-labeled anti-CEA monoclonal antibody in nude mice bearing xenografts. The tumor cell lines were WiDr, SW403, and LS174T, human colon cancer derivatives. The murine breast carcinoma cell line EMT-6 was used as a control. Tumor CEA levels (ng/g of tumor +/- standard error of the mean [SEM], measured by enzyme immunoassay (EIA) were: EMT-6, 0; WiDr, 105 +/- 5.7; LS174T, 2052 +/- 198; SW403, 17,575 +/- 1,785. The 111In-labeled monoclonal antibody was injected intravenously into mice bearing a single tumor. At 48 hours postinjection, scintiscan was performed, and the mice were killed so that biodistribution studies could be performed. The uptake of the monoclonal antibody was expressed as percent injected counts per minute per gram of tissue +/- SEM. The non-CEA-producing tumor, EMT-6, showed the lowest tumor uptake (1.4 +/- 0.3). WiDr, an intermediate CEA-producing tumor, showed some tumor uptake (16.4 +/- 1.5). The high CEA-producing tumors, SW403 and LS174T, had high tumor uptake (29.5 +/- 5.0 and 51.1 +/- 6.1, respectively). Biodistribution and scintiscan quality were closely related. Although LS174T had the best tumor uptake, SW403 had the highest CEA tumor content, indicating tumor CEA content cannot entirely predict scintiscan and biodistribution results. Tumor-to-blood (T/B), tumor-to-liver (T/L), and liver-to-blood (L/B) ratios were calculated for each animal and compared with tumor size. It was found that T/L had a negative correlation with tumor size (r = -0.72) and L/B had a positive correlation with tumor size (r = 0.94). These ratios may be useful clinically to follow response to therapy. PMID:3942992

Philben, V J; Jakowatz, J G; Beatty, B G; Vlahos, W G; Paxton, R J; Williams, L E; Shively, J E; Beatty, J D

1986-02-01

278

The Multicomponent Anthropometric Model for Assessing Body Composition in a Male Pediatric Population: A Simultaneous Prediction of Fat Mass, Bone Mineral Content, and Lean Soft Tissue  

PubMed Central

The aim of this study was to propose and cross-validate an anthropometric model for the simultaneous estimation of fat mass (FM), bone mineral content (BMC), and lean soft tissue (LST) using DXA as the reference method. A total of 408 boys (8–18 years) were included in this sample. Whole-body FM, BMC, and LST were measured by DXA and considered as dependent variables. Independent variables included thirty-two anthropometrics measurements and maturity offset determined by the Mirwald equation. From a multivariate regression model (Ymn = x(r + 1)(r + 1)n?m + ?nm), a matrix analysis was performed resulting in a multicomponent anthropometric model. The cross-validation was executed through the sum of squares of residuals (PRESS) method. Five anthropometric variables predicted simultaneously FM, BMC, and LST. Cross-validation parameters indicated that the new model is accurate with high RPRESS2 values ranging from 0.94 to 0.98 and standard error of estimate ranging from 0.01 to 0.09. The newly proposed model represents an alternative to accurately assess the body composition in male pediatric ages.

Machado, Dalmo; Oikawa, Sergio; Barbanti, Valdir

2013-01-01

279

Arsenic removal by iron-doped activated carbons prepared by ferric chloride forced hydrolysis  

Microsoft Academic Search

Ferric chloride forced hydrolysis is shown to be a good method for increasing the iron content of activated carbons (ACs). Iron content increased linearly with hydrolysis time, and ACs with iron content as high as 9.4wt.% at 24h hydrolysis time could be prepared. The increase in iron content did not produce any modification in the textural parameters determined by nitrogen

V. Fierro; G. Muñiz; G. Gonzalez-Sánchez; M. L. Ballinas; A. Celzard

2009-01-01

280

Unraveling Mechanisms Regulating Systemic Iron Homeostasis  

PubMed Central

Systemic iron balance must be tightly regulated to prevent the deleterious effects of iron deficiency and iron overload. Hepcidin, a circulating hormone that is synthesized by the liver, has emerged as a key regulator of systemic iron homeostasis. Hepcidin inhibits the absorption of dietary iron from the intestine as well as the release of iron derived from red blood cells from macrophages; thus, variation in hepcidin levels modifies the total amount of iron stored in the body as well as the availability of iron for erythropoiesis. The production of hepcidin by the liver is modulated by multiple physiological stimuli, including iron loading, inflammation, and erythropoietic activity. Investigation of the functions of the gene products mutated in inherited iron disorders using tissue culture systems and animal models has provided valuable insights into the mechanisms by which these hepcidin responses are mediated. This review focuses on recent advances in our understanding of the molecular mechanisms underlying the regulation of systemic iron homeostasis.

Finberg, Karin E.

2013-01-01

281

White beans provide more bioavailable iron than red beans: studies in poultry (Gallus gallus) and an in vitro digestion/Caco-2 model.  

PubMed

Iron-biofortification of crops is a strategy that alleviates iron deficiency. The common bean (Phaseolus vulgaris L.) is an attractive candidate for biofortification. However, beans are high in polyphenols that may inhibit iron absorption. In vitro studies have shown that iron bioavailability from white beans is higher than that from colored beans. In this study, our objective was to determine if white beans contain more bioavailable iron than red beans and to determine if the in vitro observations of bean-iron bioavailability would be evident in an in vivo feeding trial. We compared iron bioavailability between diets containing either white (Matterhorn) or red (Merlot) beans, which differ in polyphenol content. One-week-old chicks (Gallus gallus) were divided into four groups: 1. "WB": 40% white-bean diet; 2. "RB" :40% red-bean diet; 3. "WB+Fe": 40% white-bean diet; 4. "RB+Fe": 40% red-bean diet (51, 47, 179, and 175 ppm iron, respectively). Diets 1 and 2 had no supplemental iron; whereas 125 µg/g iron was added to diets 3 and 4. For 8 weeks, hemoglobin, feed consumption, and body weights were measured. Divalent metal transporter 1 (iron-uptake-transporter), duodenal-cytochrome-B (iron reductase), and ferroportin (iron-exporter) expressions were higher (p<0.05), villus-surface-area (tissue iron-deficiency adaptation) was greater in the "RB" group vs. other groups. Cecal microflora was similar between treatments. Hemoglobin, body-hemoglobin iron, and body weights were lower in the "RB" group vs. other groups (p<0.05). In vitro analysis showed lower ferritin formation (less bioavailable iron) in cells exposed to the "RB" diet. We conclude that the in vivo results support the in vitro observations; i. e., white beans contain more bioavailable iron than red beans. PMID:21792822

Tako, Elad; Glahn, Raymond P

2010-12-01

282

Iron Deposition following Chronic Myocardial Infarction as a Substrate for Cardiac Electrical Anomalies: Initial Findings in a Canine Model  

PubMed Central

Purpose Iron deposition has been shown to occur following myocardial infarction (MI). We investigated whether such focal iron deposition within chronic MI lead to electrical anomalies. Methods Two groups of dogs (ex-vivo (n?=?12) and in-vivo (n?=?10)) were studied at 16 weeks post MI. Hearts of animals from ex-vivo group were explanted and sectioned into infarcted and non-infarcted segments. Impedance spectroscopy was used to derive electrical permittivity () and conductivity (). Mass spectrometry was used to classify and characterize tissue sections with (IRON+) and without (IRON-) iron. Animals from in-vivo group underwent cardiac magnetic resonance imaging (CMR) for estimation of scar volume (late-gadolinium enhancement, LGE) and iron deposition (T2*) relative to left-ventricular volume. 24-hour electrocardiogram recordings were obtained and used to examine Heart Rate (HR), QT interval (QT), QT corrected for HR (QTc) and QTc dispersion (QTcd). In a fraction of these animals (n?=?5), ultra-high resolution electroanatomical mapping (EAM) was performed, co-registered with LGE and T2* CMR and were used to characterize the spatial locations of isolated late potentials (ILPs). Results Compared to IRON- sections, IRON+ sections had higher, but no difference in. A linear relationship was found between iron content and (p<0.001), but not (p?=?0.34). Among two groups of animals (Iron (<1.5%) and Iron (>1.5%)) with similar scar volumes (7.28%±1.02% (Iron (<1.5%)) vs 8.35%±2.98% (Iron (>1.5%)), p?=?0.51) but markedly different iron volumes (1.12%±0.64% (Iron (<1.5%)) vs 2.47%±0.64% (Iron (>1.5%)), p?=?0.02), QT and QTc were elevated and QTcd was decreased in the group with the higher iron volume during the day, night and 24-hour period (p<0.05). EAMs co-registered with CMR images showed a greater tendency for ILPs to emerge from scar regions with iron versus without iron. Conclusion The electrical behavior of infarcted hearts with iron appears to be different from those without iron. Iron within infarcted zones may evolve as an arrhythmogenic substrate in the post MI period.

Wang, Xunzhang; Yang, Hsin-Jung; Tang, Richard L. Q.; Thajudeen, Anees; Shehata, Michael; Amorn, Allen M.; Liu, Enzhao; Stewart, Brian; Bennett, Nathan; Harlev, Doron; Tsaftaris, Sotirios A.; Jackman, Warren M.; Chugh, Sumeet S.; Dharmakumar, Rohan

2013-01-01

283

On the origin of lipofuscin; the iron content of residual bodies, and the relation of these organelles to the lysosomal vacuome. A study on cultured human glial cells  

SciTech Connect

Cultured human glial cells constitute a suitable model system for the study of lipofuscinogenesis in vitro. These cells, although not post-mitotic, can be kept for several months in stable monolayers due to their display of very pronounced density-dependent inhibition of cell growth. Residual bodies, or lipofuscin pigment granules, accumulate over time in this pseudo post-mitotic cell system. I. In early dense cultures, exposed to purified rat liver mitochondriae, it was possible to follow the uptake of mitochondriae and their degradation, which was found to be incomplete and result in the formation of numerous residual bodies containing lipofuscin-type material. It was concluded that incomplete degradation of mitochondriae may be an important origin of lipofuscin. II. Dense, older cultures exposed to electron dense marker particles (colloidal thorium dioxide) accumulated these markers within endosomes, and later in secondary lysosomes of various types, including residual bodies. It was concluded that residual bodies constitute an integral part of the lysosomal vacuome system. III. Phase III glial cells were cultured on formvar-coated gold EM-grids and studied by whole cell transmission electron microscopy using TEM and STEM techniques in combination with energy dispersive X-ray microanalysis. It was found that residual bodies contained iron. This fact was taken as a further indication that lipofuscin has its origin in autophagocytosed mitochondriae and ER-material rich in metallo-enzymes. Due to their high concentration of iron, residual bodies may constitute unstable structures within the cells. Since iron is a well known catalyst of various peroxidative processes, the surrounding lysosomal membrane might be damaged, e.g. by oxidative stress, with risk for leakage of degradative lysosomal enzymes into the cell sap.

Brunk, U.T. (Linkoeping Univ. (Sweden))

1989-01-01

284

On the origin of lipofuscin; the iron content of residual bodies, and the relation of these organelles to the lysosomal vacuome. A study on cultured human glial cells.  

PubMed

Cultured human glial cells constitute a suitable model system for the study of lipofuscinogenesis in vitro. These cells, although not post-mitotic, can be kept for several months in stable monolayers due to their display of very pronounced density-dependent inhibition of cell growth. Residual bodies, or lipofuscin pigment granules, accumulate over time in this "pseudo" post-mitotic cell system. I. In early dense cultures, exposed to purified rat liver mitochondriae, it was possible to follow the uptake of mitochondriae and their degradation, which was found to be incomplete and result in the formation of numerous residual bodies containing lipofuscin-type material. It was concluded that incomplete degradation of mitochondriae may be an important origin of lipofuscin. II. Dense, older cultures exposed to electron dense marker particles (colloidal thorium dioxide) accumulated these markers within endosomes, and later in secondary lysosomes of various types, including residual bodies. It was concluded that residual bodies constitute an integral part of the lysosomal vacuome system. III. Phase III glial cells were cultured on formvar-coated gold EM-grids and studied by whole cell transmission electron microscopy using TEM and STEM techniques in combination with energy dispersive X-ray microanalysis. It was found that residual bodies contained iron. This fact was taken as a further indication that lipofuscin has its origin in autophagocytosed mitochondriae and ER-material rich in metallo-enzymes. Due to their high concentration of iron, residual bodies may constitute unstable structures within the cells. Since iron is a well known catalyst of various peroxidative processes, the surrounding lysosomal membrane might be damaged, e.g. by oxidative stress, with risk for leakage of degradative lysosomal enzymes into the cell sap. PMID:2486159

Brunk, U T

1989-01-01

285

Placental Expression of the Heme Transporter, Feline Leukemia Virus Subgroup C Receptor, Is related to Maternal Iron Status in Pregnant Adolescents123  

PubMed Central

Little is known about the expression of heme transporters in human placenta and possible associations between these transporters and maternal or neonatal iron status. To address this area of research, relative protein expression of 2 heme transporters, Feline Leukemia Virus, Subgroup C, Receptor 1 (FLVCR1) and Breast Cancer Resistance Protein (BCRP), was assessed using Western-blot analysis in human placental tissue in relation to maternal/neonatal iron status and placental iron concentration. Placental FLVCR1 (n = 71) and BCRP (n = 83) expression were assessed at term (36.6–41.7 wk gestation) in a cohort of pregnant adolescents (13–18 y of age) at high-risk of iron deficiency. Both FLVCR1 and BCRP were detected in all placental samples assayed. Placental FLVCR1 expression was positively related to placental BCRP expression (n = 69; R2 = 0.104; P < 0.05). Adolescents that were anemic at delivery had lower placental FLVCR1 expression (n = 49; P < 0.05). Placental FLVCR1 expression was positively associated with placental iron concentration at delivery (n = 61; R2 = 0.064; P < 0.05). In contrast, placental BCRP expression was not significantly associated with maternal iron status or placental iron content. Both FLVCR1 and BCRP are highly expressed in human placental tissue, but only FLVCR1 was significantly inversely associated with maternal iron status and placental iron concentration. Further analysis is needed to explore potential functional roles of FLVCR1 in human placental iron transport.

Jaacks, Lindsay M.; Young, Melissa F.; Essley, Bridget V.; McNanley, Thomas J.; Cooper, Elizabeth M.; Pressman, Eva K.; McIntyre, Allison W.; Orlando, Mark S.; Abkowitz, Janis L.; Guillet, Ronnie; O'Brien, Kimberly O.

2011-01-01

286

Lipid content in hepatic and gonadal adipose tissue parallel aortic cholesterol accumulation in mice fed diets with different omega-6 PUFA to EPA plus DHA ratios  

PubMed Central

Background & aims Diets with low omega (?)-6 polyunsaturated fatty acids (PUFA) to eicosapentaenoic acid (EPA) plus docosahexaenoic acid (DHA) ratios have been shown to decrease aortic cholesterol accumulation and have been suggested to promote weight loss. The involvement of the liver and gonadal adipose tissue (GAT) in mediating these effects is not well understood. LDL receptor null mice were used to assess the effect of an atherogenic diet with different ?-6:EPA+DHA ratios on weight gain, hepatic and GAT lipid accumulation, and their relationship to atherosclerosis. Methods Four groups of mice were fed a high saturated fat and cholesterol diet (HSF ?-6) alone, or with ?-6 PUFA to EPA+DHA ratios up to 1:1 for 32 weeks. Liver and GAT were collected for lipid and gene expression analysis. Results The fatty acid profile of liver and GAT reflected the diets. All diets resulted in similar weight gains. Compared to HSF ?-6 diet, the 1:1 ratio diet resulted in lower hepatic total cholesterol (TC) content. Aortic TC was positively correlated with hepatic and GAT TC and triglyceride. These differences were accompanied by significantly lower expression of CD36, ATP-transporter cassette A1, scavenger receptor B class 1, 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR), acetyl-CoA carboxylase alpha, acyl-CoA synthetase long-chain family member 5, and stearoyl-coenzyme A desaturase 1 (SCD1) in GAT, and HMGCR, SCD1 and cytochrome P450 7A1 in liver. Conclusions Dietary ?-6:EPA+DHA ratios did not affect body weight, but lower ?-6:EPA+DHA ratio diets decreased liver lipid accumulation, which possibly contributed to the lower aortic cholesterol accumulation.

Wang, Shu; Matthan, Nirupa R.; Wu, Dayong; Reed, Debra B.; Bapat, Priyanka; Yin, Xiangling; Grammas, Paula; Shen, Chwan-Li; Lichtenstein, Alice H.

2014-01-01

287

Chronic administration of iron and copper potentiates adipogenic effect of high fat diet in Wistar rats.  

PubMed

The primary objective of this research project is explore a possible adipogenic effect of iron and/or copper in albino Wistar rats kept on standard (STD) and high-fat (HFD) diets. The female Wistar rats in the study were divided into eight experimental groups (n = 6). Rats maintained on STD and HFD received 3 mg/l FeSO??7H?O, 4.88 mg/l CuSO? and a combination of 1.5 mg/l FeSO??7H?O and 2.44 mg/l CuSO? with drinking water. Control groups were kept on STD and HFD and received pure water without metal salts. Consumption of iron and copper in the groups of rats maintained on an STD did not produce a significant increase in weight, adipose tissue content or body mass index. However, the adipocyte size and infiltration were increased in the adipose tissue of STD-fed rats receiving a mixture of iron and copper with drinking water. The rats fed iron and copper and, especially, their combination on a HFD background had a significantly higher weight gain, adipose tissue content, morphometric parameters values and adipocyte size compared to STD- and HFD-fed controls. Iron and copper consumption produced their accumulation in the rats' adipose tissue. Moreover, the studied metals reduced adipose tissue concentration of chromium and vanadium. The lipoprotein profile and serum oxidative stress biomarkers were affected in the rats receiving the metals and STD. Hyperglycemia was observed in the rats receiving the studied metals on HFD-background. Based on the analysis of the test subjects, the study suggests that iron and copper administration, especially combined, may potentiate adipogenic effect of HFD. PMID:23657865

Tinkov, Alexey A; Polyakova, Valentina S; Nikonorov, Alexandr A

2013-06-01

288

The combined effects of ionizing radiation and weightlessness on calcium and phosphorus content in the mineral fraction of the calcified tissues in the rat skeleton  

NASA Technical Reports Server (NTRS)

Phosphorus and calcium content in the ash from skeletal bones (ribs, scapula, vertebra, and crus) of 30 rats exposed to ionizing radiation (800 rads) on the flight of the Kosmos 690 biosatellite was studied. A 10 percent decrease in ash content coefficient and 29 percent decrease in phosphorus content was found immediately after the flight, and a 9 percent decrease in phosphorus content persisted after 26 days of readaptation to terrestrial conditions.

Prokhonchukov, A. A.; Komissarova, N. A.; Kolesnik, A. G.; Novikov, L. L.

1980-01-01

289

Iron homeostasis and eye disease  

PubMed Central

Summary Iron is necessary for life, but excess iron can be toxic to tissues. Iron is thought to damage tissues primarily by generating oxygen free radicals through the Fenton reaction. We present an overview of the evidence supporting iron's potential contribution to a broad range of eye disease using an anatomical approach. Firstly, iron can be visualized in the cornea as iron lines in the normal aging cornea as well as in diseases like keratoconus and pterygium. In the lens, we present the evidence for the role of oxidative damage in cataractogenesis. Also, we review the evidence that iron may play a role in the pathogenesis of the retinal disease age-related macular degeneration. Although currently there is no direct link between excess iron and development of optic neuropathies, ferrous iron's ability to form highly reactive oxygen species may play a role in optic nerve pathology. Lastly, we discuss recent advances in prevention and therapeutics for eye disease with antioxidants and iron chelators,.

Loh, Allison; Hadziahmetovic, Majda; Dunaief, Joshua L.

2009-01-01

290

Phototherapy and malignancy: possible enhancement by iron administration and hyperbaric oxygen.  

PubMed

Photodynamic therapy (PDT) is a new therapeutic approach for the treatment of malignant tumors. Hyperbaric oxygen (HBO(2)) shows beneficial effects in various modalities of cancer interventions. Tumor cells tend to accumulate large amount of iron. There is interaction between tissue content of oxygen, iron, free radical production and tissue damage. Accumulation of intracellular iron is necessary for the production of oxygen radicals. HBO(2) increases tissue oxygen and hydrogen peroxide production in the cells. Malignant cells require iron, and exhibit more transferrin receptors. The photodynamic sensitization of human leukemic cells is achieved with accumulation of porphyrins stimulated by 5-aminolaevulanic acid (ALA) plus hemin. Further, a significant improvement in tumor response is obtained when PDT is delivered during hyperoxygenation. When PDT is combined with hyperoxygenation, the hypoxic condition is improved and the cell killing rate at various time points after PDT is significantly enhanced. Photosensitization with use of porphyrins is used with HBO(2) and PDT for treatment of certain tumors. PDT with ALA is used for treatment of actinic keratosis (AK). The combination of iron administration (by injection or oral rout), hemin, or transferrin, as a source for iron, HBO(2) as a source of oxygen under pressure and PDT as a source of generating free-radical tissue damage may be useful in the treatment of tumors. The possibility of combining HBO(2), iron, light and local photosensitizers to overcome skin tumors deserve extensive laboratory and clinical research work. Conclusively, iron, HBO(2), and PDT may have synergistic effect to hamper tumor cells. PMID:16860490

Al-Waili, Noori S; Butler, Glenn J

2006-01-01

291

The Ins and Outs of Iron Homeostasis  

NSDL National Science Digital Library

Iron is an essential element that is toxic when it accumulates in excess. Intricate regulatory mechanisms have evolved to maintain iron homeostasis within cells and between different tissues of complex organisms. This review discusses the proteins involved in iron transport and storage and their regulation in health and disease.

Adriana Donovan (Harvard Medical School, ChildrenÃÂs Hospital Boston, Dana-Farber Cancer Institute); Cindy N. Roy (Harvard Medical School ChildrenÃÂs Hospital Boston, Dana-Farber Cancer Institute); Nancy C. Andrews (Harvard Medical School ChildrenÃÂs Hospital Boston, Dana-Farber Cancer Institute,)

2006-04-01

292

Influence of the iron content on the formation process of substituted Co–Nd strontium hexaferrite prepared by the citrate precursor method  

Microsoft Academic Search

Strontium hexaferrite samples of different composition were prepared by the self-combustion method and heat-treated in air at 1100°C for 2h: SrFe12O19 (S0), Sr0.7Nd0.3Fe11.7Co0.3O19 (SS), Sr0.7Nd0.3Fe10.7Co0.3O19 (SM) and Sr0.7Nd0.3Fe8.4Co0.3O19 (SL). The phase identification of the powders was performed using XRD. Only sample SL (with the lowest iron concentration) shows well-defined peaks of the hexaferrite phase with no secondary phases. Nd–Co substitution

S. E. Jacobo; C. Herme; P. G. Bercoff

2010-01-01

293

Tissue contents and subcellular distribution of chromium and other trace metals in experimental diabetic rats after intravenous injection of Cr 50[ndash ]enriched stable isotopic tracer solution  

Microsoft Academic Search

In order to study the metabolism of essential trace elements in diabetics, we studied alloxan-diabetic rats for the distribution patterns of chromium (Cr), cobalt (Co), iron (Fe), selenium (Se), and zinc (Zn) in the liver, kidney, pancreas, and testes, as well as in the organ subcellular fractions. Normal rats were used as controls. Cr 50[ndash ]enriched stable isotopic tracer solution

Weiyue Feng; Qinfang Qian; Wenjun Ding; Zhifang Chai

2001-01-01

294

Deferasirox and deferiprone remove cardiac iron in the iron-overloaded gerbil  

PubMed Central

Introduction Deferasirox effectively controls liver iron concentration; however, little is known regarding its ability to remove stored cardiac iron. Deferiprone seems to have increased cardiac efficacy compared with traditional deferoxamine therapy. Therefore, the relative efficacy of deferasirox and deferiprone were compared in removing cardiac iron from iron-loaded gerbils. Methods Twenty-nine 8- to 10-week-old female gerbils underwent 10 weekly iron dextran injections of 200 mg/kg/week. Prechelation iron levels were assessed in 5 animals, and the remainder received deferasirox 100 mg/kg/D po QD (n = 8), deferiprone 375 mg/kg/D po divided TID (n = 8), or sham chelation (n = 8), 5 days/week for 12 weeks. Results Deferasirox reduced cardiac iron content 20.5%. No changes occurred in cardiac weight, myocyte hypertrophy, fibrosis, or weight-to-dry weight ratio. Deferasirox treatment reduced liver iron content 51%. Deferiprone produced comparable reductions in cardiac iron content (18.6% reduction). Deferiprone-treated hearts had greater mass (16.5% increase) and increased myocyte hypertrophy. Deferiprone decreased liver iron content 24.9% but was associated with an increase in liver weight and water content. Conclusion Deferasirox and deferiprone were equally effective in removing stored cardiac iron in a gerbil animal model, but deferasirox removed more hepatic iron for a given cardiac iron burden.

WOOD, JOHN C.; OTTO-DUESSEL, MAYA; GONZALEZ, IGNACIO; AGUILAR, MICHELLE I.; SHIMADA, HIRO; NICK, HANSPETER; NELSON, MARVIN; MOATS, REX

2010-01-01

295

Human brain atlas for automated region of interest selection in quantitative susceptibility mapping: application to determine iron content in deep gray matter structures.  

PubMed

The purpose of this paper is to extend the single-subject Eve atlas from Johns Hopkins University, which currently contains diffusion tensor and T1-weighted anatomical maps, by including contrast based on quantitative susceptibility mapping. The new atlas combines a "deep gray matter parcellation map" (DGMPM) derived from a single-subject quantitative susceptibility map with the previously established "white matter parcellation map" (WMPM) from the same subject's T1-weighted and diffusion tensor imaging data into an MNI coordinate map named the "Everything Parcellation Map in Eve Space," also known as the "EvePM." It allows automated segmentation of gray matter and white matter structures. Quantitative susceptibility maps from five healthy male volunteers (30 to 33 years of age) were coregistered to the Eve Atlas with AIR and Large Deformation Diffeomorphic Metric Mapping (LDDMM), and the transformation matrices were applied to the EvePM to produce automated parcellation in subject space. Parcellation accuracy was measured with a kappa analysis for the left and right structures of six deep gray matter regions. For multi-orientation QSM images, the Kappa statistic was 0.85 between automated and manual segmentation, with the inter-rater reproducibility Kappa being 0.89 for the human raters, suggesting "almost perfect" agreement between all segmentation methods. Segmentation seemed slightly more difficult for human raters on single-orientation QSM images, with the Kappa statistic being 0.88 between automated and manual segmentation, and 0.85 and 0.86 between human raters. Overall, this atlas provides a time-efficient tool for automated coregistration and segmentation of quantitative susceptibility data to analyze many regions of interest. These data were used to establish a baseline for normal magnetic susceptibility measurements for over 60 brain structures of 30- to 33-year-old males. Correlating the average susceptibility with age-based iron concentrations in gray matter structures measured by Hallgren and Sourander (1958) allowed interpolation of the average iron concentration of several deep gray matter regions delineated in the EvePM. PMID:23769915

Lim, Issel Anne L; Faria, Andreia V; Li, Xu; Hsu, Johnny T C; Airan, Raag D; Mori, Susumu; van Zijl, Peter C M

2013-11-15

296

The effect of bioactive glass content on synthesis and bioactivity of composite poly (lactic- co-glycolic acid)\\/bioactive glass substrate for tissue engineering  

Microsoft Academic Search

Tissue engineering offers a promising new approach to bone tissue grafting. One material that has received attention in this regard is the polymer poly (lactic-co-glycolic acid) (PLGA). It has the advantage of controllable bioresorption and ease of processing. Another material of interest is bioactive glass (BG), which shows the ability to stimulate osteoblastic differentiation of osteoprogenitor cells. In this study,

Jun Yao; Shula Radin; Phoebe S. Leboy; Paul Ducheyne

2005-01-01

297

Metabolic crossroads of iron and copper  

PubMed Central

Interactions between the essential dietary metals, iron and copper, have been known for many years. This review highlights recent advances in iron-copper interactions with a focus on tissues and cell types important for regulating whole-body iron and copper homeostasis. Cells that mediate dietary assimilation (enterocytes) and storage and distribution (hepatocytes) of iron and copper are considered, along with the principal users (erythroid cells) and recyclers of red cell iron (reticuloendothelial macrophages). Interactions between iron and copper in the brain are also discussed. Many unanswered questions regarding the role of these metals and their interactions in health and disease emerge from this synopsis, highlighting extensive future research opportunities.

Collins, James F; Prohaska, Joseph R; Knutson, Mitchell D

2013-01-01

298

Effects of photo-oxidative loss of FeNa 2 EDTA and of higher iron supply on chlorophyll content, growth and propagation rate in triploid watermelon cultures  

Microsoft Academic Search

Summary  Triploid watermelon (Citrullus lanatus [Thunb.] Matsum. & Nakai) Arka Manik cultures exhibited a general pale color and yellowing of lower leaves by 3–4 wk following\\u000a subculturing to fresh medium. Protecting the medium from light by covering the surface with sterile aluminum foil significantly\\u000a improved leaf color and chlorophyll content by 50–60%. Raising the concentration of FeNa2EDTA (Fe-EDTA) in the light-exposed

P. Thomas; J. B. Mythili; K. S. Shivashankara

2000-01-01

299

Iron dysregulation in Huntington's disease.  

PubMed

Huntington's disease (HD) is one of many neurodegenerative diseases with reported alterations in brain iron homeostasis that may contribute to neuropathogenesis. Iron accumulation in the specific brain areas of neurodegeneration in HD has been proposed based on observations in post-mortem tissue and magnetic resonance imaging studies. Altered magnetic resonance imaging signal within specific brain regions undergoing neurodegeneration has been consistently reported and interpreted as altered levels of brain iron. Biochemical studies using various techniques to measure iron species in human samples, mouse tissue, or in vitro has generated equivocal data to support such an association. Whether elevated brain iron occurs in HD, plays a significant contributing role in HD pathogenesis, or is a secondary effect remains currently unclear. Huntington's disease (HD) is one of many neurodegenerative diseases reported to have alterations in brain iron homeostasis. Whether elevated brain iron occurs in HD, and whether elevated iron levels play a significant contributory role in HD pathogenesis remains currently unclear. In this review, we discuss potential mechanisms by which mutant huntingtin-mediated increases in intracellular calcium and elevated intracellular iron may interact to result in elevated levels of reactive oxygen species leading to lipid peroxidation, DNA damage, and neuronal cell death. PMID:24717009

Muller, Michelle; Leavitt, Blair R

2014-08-01

300

Benefits and Problems Associated with Iron Supplementation and Fortification  

Microsoft Academic Search

As in the story of Dr Jekyll and Mr Hyde, iron (like most nutrients and particularly micronutrients) possesses both the best and the worst possible qualities. Both an inadequate supply of iron to body tissues and excessive iron accumulation within the body lead to significant morbidity. So, iron is an intriguing compound, with a wide range of benefits when it

Serge Hercberg

301

Pagophagia in iron deficiency anemia.  

PubMed

The relationship between pagophagia (ice pica) and iron deficiency anemia was studied. All 81 patients with iron deficiency anemia defined as hemoglobin <12.0 g/dl and ferritin level <12 ng/ml were interviewed about their habits of eating ice or other non-food substances. Pagophagia was defined as compulsive and repeated ingestion of at least one tray of ice or ice eating which was relieved after iron administration. Pagophagia was present in 13 patients (16.0%). All patients who received oral iron were periodically assessed employing a questionnaire on pagophagia and laboratory data. Iron therapy can cure the pagophagia earlier than hemoglobin recovery and repair of tissue iron deficiency. Although the pathogenesis of pagophagia is unclear, a biochemical approach involving the central nervous system might elucidate the mechanism underlying these abnormal behaviors. PMID:24850454

Uchida, Tatsumi; Kawati, Yasunori

2014-04-01

302

Differential responses of anti-oxidants enzymes, lipoxygenase activity, ascorbate content and the production of saponins in tissue cultured root of mountain Panax ginseng C.A. Mayer and Panax quinquefolium L. in bioreactor subjected to methyl jasmonate stress  

Microsoft Academic Search

The oxidative status (anti-oxidative enzymes and anti-oxidants), saponins accumulation H2O2 content and thiobarbituric acid reacting substances (TBARS) of tissue cultured roots of Panax ginseng (PG) and Panax quinquefolium (PQ) exposed to methyl jasmonate (MJ-200?M) for 0, 3, 5, 7 and 9 days were studied in 5L (working volume-4L) airlift bioreactors. Saponin accumulation was enhanced 4-fold higher than the cultivated ginseng

Mohammad Babar Ali; Kee-Won Yu; Eun-Joo Hahn; Kee-Yoeup Paek

2005-01-01

303

Glucose homeostasis and tissue transcript content of insulin signaling intermediates in four inbred strains of mice: C57BL/6, C57BLKS/6, DBA/2, and 129X1.  

PubMed

Transgenic mice phenotypes generally depend on the background strains used in their creation. To examine the effects of genetic background on insulin signaling, we analyzed glucose homeostasis in four inbred strains of mice [C57BL/6 (B6), C57BLKS/6 (KLS), DBA/2 (DBA), and 129X1] and quantitated mRNA content of insulin receptor (IR) and its substrates in insulin-responsive tissues. At 2 months, the male B6 mouse is the least glucose-tolerant despite exhibiting similar insulin sensitivity and first-phase insulin secretion as the other strains. The 129X1 male mouse islet contains less insulin and exhibits a higher threshold for glucose-stimulated first-phase insulin secretion than the other strains. Female mice generally manifest better glucose tolerance than males, which is likely due to greater insulin sensitivity in liver and adipose tissue, a robust first-phase insulin secretion in B6 and KLS females, and improved insulin sensitivity in muscle in DBA and 129X1 females. At 6 months, although males exhibit improved first-phase insulin secretion, their physiology was relatively unchanged, whereas female B6 and KLS mice became less insulin sensitive. Gene expression of insulin signaling intermediates in insulin-responsive tissues was generally not strain dependent with the cell content of IR mRNA being highest. IR substrate (IRS)-1 and IRS-2 mRNA are ubiquitously expressed and IRS-3 and IRS-4 mRNA were detected in significant amounts in fat and brain tissues, respectively. These data indicate strain-, gender-, and age-dependent tissue sensitivity to insulin that is generally not associated with transcript content of IR or its substrates and should be taken into consideration during phenotypic characterization of transgenic mice. PMID:15044376

Goren, H Joseph; Kulkarni, Rohit N; Kahn, C Ronald

2004-07-01

304

Air oxidation of hydrazine. 1. Reaction kinetics on natural kaolinites, halloysites, and model substituent layers with varying iron and titanium oxide and O- center contents  

NASA Technical Reports Server (NTRS)

Air oxidation of hydrazine was studied by using a group of kaolinites, halloysites, and substituent oxides as models for the tetrahedral and octahedral sheets. The rate was found to be linear with oxygen. The stoichiometry showed that oxygen was the primary oxidant and that dinitrogen was the only important nitrogen-containing product. The rates on kaolinites were strongly inhibited by water. Those on three-dimensional silica and gibbsite appeared not to be. That on a supposedly layered silica formed from a natural kaolinite by acid leaching showed transitional behavior--slowed relative to that expected from a second-order reaction relative to that on the gibbsite and silica but faster than those on the kaolinites. The most striking result of the reaction was the marked increase in the rate of reaction of a constant amount of hydrazine as the amount of clay was increased. The increase was apparent (in spite of the water inhibition at high conversions) over a 2 order of magnitude variation of the clay weight. The weight dependence was taken to indicate that the role of the clay is very important, that the number of reactive centers is very small, or that they may be deactivated over the course of the reaction. In contrast to the strong dependence on overall amount of clay, the variation of amounts of putative oxidizing centers, such as structural Fe(III), admixed TiO2 or Fe2O3, or O- centers, did not result in alteration of the rate commensurate with the degree of variation of the entity in question. Surface iron does play some role, however, as samples that were pretreated with a reducing agent were less active as catalysts than the parent material. These results were taken to indicate either that the various centers interact to such a degree that they cannot be considered independently or that the reaction might proceed by way of surface complexation, rather than single electron transfers.

Coyne, L.; Mariner, R.; Rice, A.

1991-01-01

305

Iron Ore.  

National Technical Information Service (NTIS)

Iron ore is an important mineral commodity because it is the primary source of iron, the metal most widely used by man. World production of iron ore in 1977 was estimated at 840 million tons, and an estimated 350 million tons was shipped in international ...

F. L. Klinger

1978-01-01

306

Quantification of amounts and (13)C content of metabolites in brain tissue using high- resolution magic angle spinning (13)C NMR spectroscopy.  

PubMed

Metabolic pathway mapping using (13)C NMR spectroscopy has been used extensively to study interactions between neurons and glia in the brain. Established extraction procedures of brain tissue are time consuming and may result in degradation of labile substances. We examined the potential of mapping (13)C-enriched compounds in intact brain tissue using high-resolution magic angle spinning (HR-MAS) NMR spectroscopy. Sprague-Dawley rats received an intraperitoneal injection of [1,6-(13)C]glucose, and 15 min later the animals were subjected to microwave fixation of the brain. Quantification of concentration and (13)C labelling of metabolites in intact rat thalamus were carried out based on exogenous ethylene glycol concentrations measured from (1)H NMR spectra using an ERETIC (Electronic REference To access In vivo Concentrations) signal. The results from intact tissue were compared with those from perchloric acid-extracted brain tissue. Amounts of (13)C labelling at different positions (C2, C3 and C4) in glutamate, glutamine, gamma-aminobutyric acid and aspartate measured in either intact tissue or perchloric acid extracts were not significantly different. Proton NMR spectra were used for quantification of six different amino acids plus lactate, inositol, N-acetylaspartate, creatine and phosphocreatine. Again, results were very similar when comparing the methods. To our knowledge, this is the first time quantitative (13)C NMR spectroscopy measurements have been carried out on intact brain tissue ex vivo using the HR-MAS technique. The results show that HR-MAS (13)C NMR spectroscopy in combination with (1)H NMR spectroscopy and the ERETIC method is useful for metabolic studies of intact brain tissue ex vivo. PMID:19012315

Risa, Oystein; Melø, Torun Margareta; Sonnewald, Ursula

2009-04-01

307

Beneficial Effects of Chromium on Glucose and Lipid Variables in Control and Somatotropin-Treated Pigs Are Associated with Increased Tissue Chromium and Altered Tissue Copper, Iron, and Zinc1  

Microsoft Academic Search

Chromium (Cr) and somatotropin have been shown to increase lean body mass in pigs but by independent mechanisms. Somatotropin and Cr also affect blood glucose, lipids, and tissue trace metal concentrations. Twenty-four castrated male pigs were divided into four groups: 1 ) control basal diet; 2 ) basal diet + 300 mg of Cr\\/kg of diet as Cr picolinate; 3

Richard A. Anderson; Noella A. Bryden; Christina M. Evock-Clover; Norman C. Steele

308

Identification of rice cultivars with low brown rice mixed cadmium and lead contents and their interactions with the micronutrients iron, zinc, nickel and manganese.  

PubMed

Paddy fields in mining areas are usually co-contaminated by a cocktail of mixed toxic heavy metals (e.g., Cd and Pb in Pb/Zn mines). However, previous studies on rice cultivars screened for effective metal exclusion have mostly focused on individual metals, and have been conducted under pot-trial or hydroponic solution conditions. This study identified rice cultivars with both low Cd and Pb accumulation under Cd- and Pb-contaminated field conditions, and the interactions of the toxic elements Cd and Pb with the micronutrient elements Fe, Zn, Mn and Ni were also studied. Among 32 rice cultivars tested, there were significant differences in Cd (0.06-0.59 mg/kg) and Pb (0.25-3.15 mg/kg) levels in their brown rice, and similar results were also found for the micronutrient elements. Significant decreases in concentrations of Fe and Mn were detected with increasing Cd concentrations and a significant elevation in Fe, Mn and Ni with increasing Pb concentrations. A similar result was also shown by Cd and Ni. Three cultivars were identified with a combination of low brown rice Cd and Pb, high micronutrient and grain yield (Wufengyou 2168, Tianyou 196 and Guinongzhan). Present results suggest that it is possible to breed rice cultivars with low mixed toxic element (Cd, Pb) and high micronutrient contents along with high grain yields, thus ensuring food safety and quality. PMID:23520849

Li, Bing; Wang, Xun; Qi, Xiaoli; Huang, Lu; Ye, Zhihong

2012-01-01

309

Mineralogical Study of GRA95209 Lodranite in Comparison with Acapulcoites and IAB Iron Meteorites  

NASA Astrophysics Data System (ADS)

High ZnO content in both GRA95209 chromite and IAB iron meteorites and heterogenous metal distribution in GRA95209 and Caddo County IAB iron meteorite might suggest the common formation process between GRA95209 and IAB iron meteorites.

Chikami, J.

2001-03-01

310

Mineralogical Study of GRA95209 Lodranite in Comparison with Acapulcoites and IAB Iron Meteorites  

Microsoft Academic Search

High ZnO content in both GRA95209 chromite and IAB iron meteorites and heterogenous metal distribution in GRA95209 and Caddo County IAB iron meteorite might suggest the common formation process between GRA95209 and IAB iron meteorites.

J. Chikami

2001-01-01

311

THE IMPORTANCE OF OBTAINING INFORMATION ON THE SPECIFIC CONTENT OF TISSUE ENZYMES METABOLIZING ORGANOPHOSPHORUS PESTICIDES, PRIOR TO DETERMINING VMAX, KM VALUES FOR USE IN PBPK MODELS  

EPA Science Inventory

Physiological pharmacokinetic\\pharmacodynamic models require Vmax, Km values for the metabolism of OPs by tissue enzymes. Current literature values cannot be easily used in OP PBPK models (i.e., parathion and chlorpyrifos) because standard methodologies were not used in their ...

312

THE IMPORTANCE OF OBTAINING INFORMATION ON THE SPECIFIC CONTENT OF TISSUE ENZYMES METABOLIZING ORGANOPHOSPHORUS PESTICIDES, PRIOR TO DETERMINE VMAX, KM VALUES FOR USE IN PBPK MODELS  

EPA Science Inventory

Physiological pharmacokinetic/pharmacodynamic models require Vmax, Km values for the metabolism of OPs by tissue enzymes. Current literature values cannot be easily used in OP PBPK models (i.e., parathion and chlorpyrifos) because standard methodologies were not used in their ...

313

ImageMiner: a software system for comparative analysis of tissue microarrays using content-based image retrieval, high-performance computing, and grid technology  

PubMed Central

Objective and design The design and implementation of ImageMiner, a software platform for performing comparative analysis of expression patterns in imaged microscopy specimens such as tissue microarrays (TMAs), is described. ImageMiner is a federated system of services that provides a reliable set of analytical and data management capabilities for investigative research applications in pathology. It provides a library of image processing methods, including automated registration, segmentation, feature extraction, and classification, all of which have been tailored, in these studies, to support TMA analysis. The system is designed to leverage high-performance computing machines so that investigators can rapidly analyze large ensembles of imaged TMA specimens. To support deployment in collaborative, multi-institutional projects, ImageMiner features grid-enabled, service-based components so that multiple instances of ImageMiner can be accessed remotely and federated. Results The experimental evaluation shows that: (1) ImageMiner is able to support reliable detection and feature extraction of tumor regions within imaged tissues; (2) images and analysis results managed in ImageMiner can be searched for and retrieved on the basis of image-based features, classification information, and any correlated clinical data, including any metadata that have been generated to describe the specified tissue and TMA; and (3) the system is able to reduce computation time of analyses by exploiting computing clusters, which facilitates analysis of larger sets of tissue samples.

Foran, David J; Yang, Lin; Hu, Jun; Goodell, Lauri A; Reiss, Michael; Wang, Fusheng; Kurc, Tahsin; Pan, Tony; Sharma, Ashish; Saltz, Joel H

2011-01-01

314

Moderate doses of conjugated linoleic acid isomers mix contribute to lowering body fat content maintaining insulin sensitivity and a noninflammatory pattern in adipose tissue in mice  

Microsoft Academic Search

Conjugated linoleic acid (CLA) modulates body composition, especially by reducing adipose tissue. However, despite the increasing knowledge about CLA's beneficial effects on obesity management, the mechanism of action is not yet fully understood. Furthermore, in some human studies fat loss is accompanied by impairment in insulin sensitivity, especially when using the trans-10,cis-12 isomer. The aim of this work was to

Pilar Parra; Francisca Serra; Andreu Palou

2010-01-01

315

Hepatic iron accumulation over time in European starlings (Sturnus vulgaris) fed two levels of iron.  

PubMed

European starlings (Sturnus vulgaris) were used as a passerine bird model to examine the effect of dietary iron on the level of hepatic iron in birds. Nestling and fledgling starlings (n = 56) were raised on a controlled-iron diet. When birds maintained constant body weight, they were assigned in pairs to cages, and baseline sampling was performed. Pairs were then assigned to one of two diets: the controlled-iron diet (168 ppm, dry basis) or a high-iron diet (3,035 ppm, dry basis). Dry-matter intake and iron consumption were recorded. Dry-matter intake did not differ between the dietary treatment groups and was stable during treatment periods. Iron intake was higher in the high-iron group (P < 0.05). Birds were euthanized at baseline, 8 wk, and 16 wk. Body, liver, and spleen weights were measured. Hepatic iron and copper concentrations were determined. Body weight did not differ between the two treatment groups or among individuals for the study duration. Liver iron concentration differed over time and between treatment groups. Birds receiving both treatments had similar liver iron content at week 8 (3,107 +/- 228.6 ppm and 3,122 +/- 306.2 ppm high and controlled iron, respectively; P > 0.05), but by week 16, birds consuming the high-iron diet had greater hepatic iron levels than those consuming the controlled-iron diet (5,929 +/- 937.2 ppm and 3,683 +/- 229.5 ppm high and controlled iron, respectively; P < 0.05). Birds on the controlled-iron diet also had higher hepatic iron at 16 wk than at 8 wk. Liver copper decreased over time in all birds regardless of treatment. Results show that both dietary iron level and duration of time influenced hepatic iron storage. The controlled-iron diets still allowed accumulation of hepatic iron in an 8-wk period. PMID:11428395

Crissey, S D; Ward, A M; Block, S E; Maslanka, M T

2000-12-01

316

Toxic (Pb, Cd, Hg) and essential (Fe, Cu, Zn, Mn) metal content of liver tissue of some domestic and bush animals in Ghana.  

PubMed

Accumulation of toxic metals in liver, a rich natural source of essential elements, can present health risks to regular consumers of liver. A total of 35 fresh liver samples of cow, sheep, goat, pig, grass-cutter (Thryonomys swinderianus), gaint rat (Cricetomys gambianus), red deer (Cervus elaphus), chicken and antelope (Antilocapra americana) were obtained from three different markets in Accra and Kumasi, Ghana. Samples were analyzed using atomic absorption spectrometry and an automatic mercury analyzer. Levels of iron in the grass-cutter and pig of 500.5-645.4 mg kg(-1) were the highest in the animal livers examined. Mn concentrations were highest in grass-cutter and rat liver, ranging 16.5-30.2 mg kg(-1). The safe Cu and Zn permissible limits of 20 and 50 mg kg(-1) were exceeded in 70 and 75% of the liver samples, respectively. Generally, for each animal group studied, at least 50% of the sample livers exceeded the Cd permissible limit of 0.5 mg kg(-1). The levels of Pb, which ranged 1.3-13.8 mg kg(-1), exceeded the proposed European Commission (EC) limit of 0.5 mg kg(-1). Care must be taken by regular consumers of the iron-rich animal livers of grass-cutter, pig and rat because they also had the highest levels of Pb (in grass-cutter and pig) and Cd (in grass-cutter, rat and pig). The liver samples analyzed for Hg had values far below the permissible limit of 0.5 mg kg(-1). PMID:24784805

Adei, Evans; Forson-Adaboh, Kwadwo

2008-12-01

317

Organic Matter and Silicon in Relation to the Crystallinity of Soil Iron Oxides  

Microsoft Academic Search

The contents of pyrophosphate-extractable carbon and iron, EDTA-extractable iron, dithionite-EDTA-extractable iron and silicon, total carbon, and sodium hydroxide-extractable silicon were determined in thirty soil samples from Denmark and Tanzania in order to investigate the general influence of organic matter and silicon on the crystallinity of soil iron oxides. The ratio between the contents of EDTA-extractable iron and dithionite-EDTA-extractable iron, both

Ole K. Borggaard

1985-01-01

318

Impact of algal diets and emulsions on the fatty acid composition and content of selected tissues of adult broodstock of the Chilean scallop Argopecten pupuratus (Lamarck, 1819)  

Microsoft Academic Search

The impact of dietary fatty acids on the fatty acid composition and content in different organs (digestive gland, adductor muscle and male and female gonad) of Argopecten purpuratus was evaluated during the process of gonad maturation under controlled laboratory conditions. A mixed algal diet of Isochrysis galbana (clone T-Iso), Pavlova lutheri, Chaetoceros gracilis and Tetraselmis suecica was either fed alone

Marrit Caers; Peter Coutteau; Patrick Sorgeloos; Gonzalo Gajardo

2003-01-01

319

Iron uptake and translocation by macrocystis pyrifera  

SciTech Connect

Parameters of iron uptake have been determined for blade tissue of Macrocystis pyrifera (L.) C. Ag. These include the effects of iron concentration, light, various inhibitors, and blade type. All experiments were conducted in the defined artificial seawater Aquil. Iron uptake is light independent, energy dependent, and dependent on the reduction from Fe/sup 3+/ to Fe/sup 2+/. Iron is concentrated in the sieve tube exudate; exudate analysis revealed the presence of other micronutrients. Iron and other micronutrient translocation is discussed.

Manley, S.L.

1981-10-01

320

Iron plaque formation and morphoanatomy of roots from species of restinga subjected to excess iron.  

PubMed

The restingas, a sandy coastal plain ecosystem of Brazil, have received an additional amount of iron due to the activity of mining industries. The present study aims to characterize morphoanatomically and histochemically the iron plaque formation on roots of Ipomoea pes-caprae L. and Canavalia rosea DC, cultivated in hydroponic solution with and without excess iron. The iron plaque formation as well as changes in the external morphology of the lateral roots of both species were observed after the subjection to excess iron. Changes in the nutrient uptake, and in the organization and form of the pericycle and cortex cells were observed for both species. Scanning electron microscopy showed evident iron plaques on the whole surface of the root. The iron was histolocalized in all root tissues of both species. The species of restinga studied here formed iron plaque in their roots when exposed to excess of this element, which may compromise their development in environments polluted by particulated iron. PMID:22169228

Siqueira-Silva, Advanio Inácio; da Silva, Luzimar Campos; Azevedo, Aristéa Alves; Oliva, Marco Antonio

2012-04-01

321

Measurement of Local Strains in Intervertebral Disc Anulus Fibrosus Tissue under Dynamic Shear: Contributions of Matrix Fiber Orientation and Elastin Content  

PubMed Central

Shear strain has been implicated as an initiator of intervertebral disc anulus failure, however a clear, multi-scale picture of how shear strain affects the tissue microstructure has been lacking. The purposes of this study were to measure microscale deformations in anulus tissue under dynamic shear in two orientations, and to determine the role of elastin in regulating these deformations. Bovine AF tissue was simultaneously shear loaded and imaged using confocal microscopy following either a buffer or elastase treatment. Digital image analysis was used to track through time local shear strains in specimens sheared transversely, and stretch and rotation of collagen fiber bundles in specimens sheared circumferentially. The results of this study suggest that sliding does not occur between AF plies under shear, and that interlamellar connections are governed by collagen and fibrilin rather than elastin The transverse shear modulus was found to be approximately 1.6 times as high in plies the direction of the collagen fibers as in plies across them. Under physiological levels of in-plane shear, fiber bundles stretched and re-oriented linearly. Elastin was found to primarily stiffen plies transversely. We conclude that alterations in the elastic fiber network, as found with IVD herniation and degeneration, can therefore be expected to significantly influence the AF response to shear making it more susceptible to micro failure under bending or torsion loading.

Michalek, Arthur J; Buckley, Mark R; Bonassar, Lawrence J; Cohen, Itai; Iatridis, James C

2009-01-01

322

The effect of bioactive glass content on synthesis and bioactivity of composite poly (lactic-co-glycolic acid)/bioactive glass substrate for tissue engineering.  

PubMed

Tissue engineering offers a promising new approach to bone tissue grafting. One material that has received attention in this regard is the polymer poly (lactic-co-glycolic acid) (PLGA). It has the advantage of controllable bioresorption and ease of processing. Another material of interest is bioactive glass (BG), which shows the ability to stimulate osteoblastic differentiation of osteoprogenitor cells. In this study, we reported on the optimal synthesis parameters and the kinetics of formation of calcium phosphate (Ca-P) phase at the surface of PLGA/BG composites. The formation of calcium phosphate layer was confirmed using scanning electron microscopy/energy dispersive X-ray analysis (SEM/EDXA). PLGA-30%BG microspheres based porous scaffolds for bone tissue engineering were examined for their ability to promote osteogenesis of marrow stromal cells (MSC). This porous scaffold supported both MSC proliferation and promoted MSC differentiation into cells expressing the osteoblast phenotype. It therefore demonstrates significant potential as a bone replacement material. PMID:15576167

Yao, Jun; Radin, Shula; S Leboy, Phoebe; Ducheyne, Paul

2005-05-01

323

Disposition, accumulation and toxicity of iron fed as iron (II) sulfate or as sodium iron EDTA in rats.  

PubMed

A study was performed to provide data on the disposition, accumulation and toxicity of sodium iron EDTA in comparison with iron (II) sulfate in rats on administration via the diet for 31 and 61 days. Clinical signs, body weights, food consumption, food conversion efficiency, hematology, clinical chemistry and pathology of selected organs were used as criteria for disclosing possible harmful effects. Determination of iron and total iron binding capacity in blood plasma and non-heme iron analysis in liver, spleen and kidneys were used to assess the disposition and accumulation of iron originating from sodium iron EDTA or iron (II) sulfate. It was concluded that, under the conditions of the present study, iron is accumulated from the diet in liver, spleen and kidneys in a dose-dependent manner, and iron derived from FeEDTA is taken up and/or accumulated less efficiently in liver and spleen than iron from FeSO(4). Moreover, feeding iron up to 11.5 and 11.2 mg/kg body weight/day, derived from FeSO(4) and FeEDTA, respectively, did not result in tissue iron excess nor in any other toxicologically significant effects. PMID:11278058

Appel, M J; Kuper, C F; Woutersen, R A

2001-03-01

324

Iron homeostasis and toxicity in retinal degeneration  

PubMed Central

Iron is essential for many metabolic processes but can also cause damage. As a potent generator of hydroxyl radical, the most reactive of the free radicals, iron can cause considerable oxidative stress. Since iron is absorbed through diet but not excreted except through menstruation, total body iron levels build up with age. Macular iron levels increase with age, in both men and women. This iron has the potential to contribute to retinal degeneration. Here we present an overview of the evidence suggesting that iron may contribute to retinal degenerations. Intraocular iron foreign bodies cause retinal degeneration. Retinal iron buildup resulting from hereditary iron homeostasis disorders aceruloplasminemia, Friedreich’s Ataxia, and panthothenate kinase associated neurodegeneration cause retinal degeneration. Mice with targeted mutation of the iron exporter ceruloplasmin have age-dependent retinal iron overload and a resulting retinal degeneration with features of age-related macular degeneration (AMD). Post mortem retinas from patients with AMD have more iron and the iron carrier transferrin than age- matched controls. Over the past ten years much has been learned about the intricate network of proteins involved in iron handling. Many of these, including transferrin, transferrin receptor, divalent metal transporter 1, ferritin, ferroportin, ceruloplasmin, hephaestin, iron regulatory protein, and histocompatibility leukocyte antigen class I-like protein involved in iron homeostasis (HFE) have been found in the retina. Some of these proteins have been found in the cornea and lens as well. Levels of the iron carrier transferrin are high in the aqueous and vitreous humors. The functions of these proteins in other tissues, combined with studies on cultured ocular tissues, genetically engineered mice, and eye exams on patients with hereditary iron diseases provide clues regarding their ocular functions. Iron may play a role in a broad range of ocular diseases, including glaucoma, cataract, AMD, and conditions causing intraocular hemorrhage. While iron deficiency must be prevented, the therapeutic potential of limiting iron induced ocular oxidative damage is high. Systemic, local, or topical iron chelation with an expanding repertoire of drugs has clinical potential.

He, Xining; Hahn, Paul; Iacovelli, Jared; Wong, Robert; King, Chih; Bhisitkul, Robert; Massaro-Giordano, Mina; Dunaief, Joshua L.

2007-01-01

325

Tissue-resident macrophages  

PubMed Central

Tissue-resident macrophages are a heterogeneous population of immune cells that fulfill tissue-specific and niche-specific functions. These range from dedicated homeostatic functions, such as clearance of cellular debris and iron processing, to central roles in tissue immune-surveillance, response to infection and the resolution of inflammation. Recent studies highlight marked heterogeneity in the origins of tissue macrophages that arise from hematopoietic versus self-renewing embryo-derived populations. We discuss the tissue–niche-specific factors that dictate cell phenotype, the definition of which will allow novel strategies to promote the restoration of tissue homeostasis. Understanding the mechanisms that dictate tissue macrophage heterogeneity should explain why simplified paradigms of macrophage activation do not explain the extent of heterogeneity seen in vivo.

Davies, Luke C.; Jenkins, Stephen J.; Allen, Judith E.; Taylor, Philip R.

2014-01-01

326

Iron refractory iron deficiency anemia  

PubMed Central

Iron refractory iron deficiency anemia is a hereditary recessive anemia due to a defect in the TMPRSS6 gene encoding Matriptase-2. This protein is a transmembrane serine protease that plays an essential role in down-regulating hepcidin, the key regulator of iron homeostasis. Hallmarks of this disease are microcytic hypochromic anemia, low transferrin saturation and normal/high serum hepcidin values. The anemia appears in the post-natal period, although in some cases it is only diagnosed in adulthood. The disease is refractory to oral iron treatment but shows a slow response to intravenous iron injections and partial correction of the anemia. To date, 40 different Matriptase-2 mutations have been reported, affecting all the functional domains of the large ectodomain of the protein. In vitro experiments on transfected cells suggest that Matriptase-2 cleaves Hemojuvelin, a major regulator of hepcidin expression and that this function is altered in this genetic form of anemia. In contrast to the low/undetectable hepcidin levels observed in acquired iron deficiency, in patients with Matriptase-2 deficiency, serum hepcidin is inappropriately high for the low iron status and accounts for the absent/delayed response to oral iron treatment. A challenge for the clinicians and pediatricians is the recognition of the disorder among iron deficiency and other microcytic anemias commonly found in pediatric patients. The current treatment of iron refractory iron deficiency anemia is based on parenteral iron administration; in the future, manipulation of the hepcidin pathway with the aim of suppressing it might become an alternative therapeutic approach.

De Falco, Luigia; Sanchez, Mayka; Silvestri, Laura; Kannengiesser, Caroline; Muckenthaler, Martina U.; Iolascon, Achille; Gouya, Laurent; Camaschella, Clara; Beaumont, Carole

2013-01-01

327

Analysis of the Cu, Fe, and Zn contents in cytochrome C oxidases from different species and tissues by proton-induced X-ray emission (PIXE)  

SciTech Connect

The Cu, Fe and Zn contents in isolated cytochrome c oxidase preparations from heart, liver, diaphragm or kidney of bovine, pig and rat was measured by proton-induced X-ray emission (PIXE). The average Cu/2Fe ratio was 2.73 and Zn/2Fe ratio 0.98. Correspondingly a Cu/Zn ratio of 2.76 was found. Dialysis of the bovine heart enzyme against increasing EDTA concentrations up to 30 mM did not change this result. It is concluded that all isozymes of mammalian cytochrome c oxidase contain 3 Cu, 2 Fe and 1 Zn per monomeric catalytic unit.

Bombelka, E.; Richter, F.W.; Stroh, A.; Kadenbach, B.

1986-11-14

328

Iron overload in urban Africans in the 1990s  

PubMed Central

BACKGROUND—In a previously described model, heterozygotes for an African iron loading locus develop iron overload only when dietary iron is high, but homozygotes may do so with normal dietary iron. If an iron loading gene is common, then homozygotes with iron overload will be found even in an urban population where traditional beer, the source of iron, is uncommon.?AIMS—To determine whether iron overload and the C282Y mutation characteristic of hereditary haemochromatosis are readily identifiable in an urban African population.?METHODS—Histological assessment, hepatocellular iron grading, and dry weight non-haem iron concentration were determined in post mortem tissue from liver, spleen, heart, lungs, and skin. DNA of subjects with elevated hepatic iron indexes was analysed for the C282Y mutation. Iron concentrations in other tissues were compared.?RESULTS—A moderate increase (>30 µmol/g) in hepatic iron concentrations was found in 31 subjects (23%; 95% confidence interval 15.9 to 30.1%), and they were considerably elevated (>180 µmol/g) in seven subjects (5.2%; 95% confidence interval 1.5 to 8.9%). Appreciably elevated hepatic iron concentrations were associated with heavy iron deposition in both hepatocytes and macrophages, and either portal fibrosis or cirrhosis. All were negative for the C282Y mutation. Very high concentrations were uncommon in subjects dying in hospital. Concentrations of iron in spleen, heart, lung, and skin were significantly higher in subjects with elevated hepatic iron.?CONCLUSIONS—Iron overload is readily identified among urban Africans and is associated with hepatic damage and iron loading of several tissues. The condition is unrelated to the genetic mutation found in hereditary haemochromatosis.???Keywords: haemosiderosis; cirrhosis; iron; liver; Africa; haemochromatosis

Gangaidzo, I; Moyo, V; Saungweme, T; Khumalo, H; Charakupa, R; Gomo, Z; Loyevsky, M; Stearman, R; Vaute, T; Enquist, E; Rouault, T; Gordeuk, V

1999-01-01

329

Iron regulatory proteins in pathobiology.  

PubMed Central

The capacity of readily exchanging electrons makes iron not only essential for fundamental cell functions, but also a potential catalyst for chemical reactions involving free-radical formation and subsequent oxidative stress and cell damage. Cellular iron levels are therefore carefully regulated in order to maintain an adequate substrate while also minimizing the pool of potentially toxic 'free iron'. Iron homoeostasis is controlled through several genes, an increasing number of which have been found to contain non-coding sequences [i.e. the iron-responsive elements (IREs)] which are recognized at the mRNA level by two cytoplasmic iron-regulatory proteins (IRP-1 and IRP-2). The IRPs belong to the aconitase superfamily. By means of an Fe-S-cluster-dependent switch, IRP-1 can function as an mRNA-binding protein or as an enzyme that converts citrate into isocitrate. Although structurally and functionally similar to IRP-1, IRP-2 does not seem to assemble a cluster nor to possess aconitase activity; moreover, it has a distinct pattern of tissue expression and is modulated by means of proteasome-mediated degradation. In response to fluctuations in the level of the 'labile iron pool', IRPs act as key regulators of cellular iron homoeostasis as a result of the translational control of the expression of a number of iron metabolism-related genes. Conversely, various agents and conditions may affect IRP activity, thereby modulating iron and oxygen radical levels in different pathobiological settings. As the number of mRNAs regulated through IRE-IRP interactions keeps growing, the definition of IRPs as iron-regulatory proteins may in the near future become limiting as their role expands to other essential metabolic pathways.

Cairo, G; Pietrangelo, A

2000-01-01

330

Cellular Iron Distribution in Bacillus anthracis  

PubMed Central

Although successful iron acquisition by pathogens within a host is a prerequisite for the establishment of infection, surprisingly little is known about the intracellular distribution of iron within bacterial pathogens. We have used a combination of anaerobic native liquid chromatography, inductively coupled plasma mass spectrometry, principal-component analysis, and peptide mass fingerprinting to investigate the cytosolic iron distribution in the pathogen Bacillus anthracis. Our studies identified three of the major iron pools as being associated with the electron transfer protein ferredoxin, the miniferritin Dps2, and the superoxide dismutase (SOD) enzymes SodA1 and SodA2. Although both SOD isozymes were predicted to utilize manganese cofactors, quantification of the metal ions associated with SodA1 and SodA2 in cell extracts established that SodA1 is associated with both manganese and iron, whereas SodA2 is bound exclusively to iron in vivo. These data were confirmed by in vitro assays using recombinant protein preparations, showing that SodA2 is active with an iron cofactor, while SodA1 is cambialistic, i.e., active with manganese or iron. Furthermore, we observe that B. anthracis cells exposed to superoxide stress increase their total iron content more than 2-fold over 60 min, while the manganese and zinc contents are unaffected. Notably, the acquired iron is not localized to the three identified cytosolic iron pools.

Tu, Wang Yung; Pohl, Susanne; Gray, Joe; Robinson, Nigel J.; Harwood, Colin R.

2012-01-01

331

Progressive Brain Iron Accumulation in Neuroferritinopathy Measured by the Thalamic T2* Relaxation Rate  

PubMed Central

SUMMARY Neuroferritinopathy is an autosomal dominant extrapyramidal movement disorder, caused by FTL gene mutations. Iron decreases the MR T2* decay time, therefore increasing the R2* (R2* = 1 /T2*), which correlates with brain tissue iron content. 3T structural and quantitative MR imaging assessment of R2* in 10 patients with neuroferritinopathy demonstrated a unique pattern of basal ganglia cavitation involving the substantia nigra in older patients and increasing thalamic R2* signal intensity detectable during 6 months. Increasing R2* signal intensity in the thalamus correlated with progression on a clinical rating scale measuring dystonia severity. Thalamic R2* signal intensity is a clinically useful method of objectively tracking disease progression in this form of neurodegeneration with brain iron accumulation.

McNeill, A.; Gorman, G.; Khan, A.; Horvath, R.; Blamire, A.M.; Chinnery, P.F.

2014-01-01

332

Sex differences in iron status and hepcidin expression in rats.  

PubMed

Studies have shown that men and women exhibit significant differences regarding iron status. However, the effects of sex on iron accumulation and distribution are not well established. In this study, female and male Sprague-Dawley rats were killed at 4 months of age. Blood samples were analyzed to determine the red blood cell (RBC) count, hemoglobin (Hb) concentration, hematocrit (Hct), and mean red blood cell volume (MCV). The serum samples were analyzed to determine the concentrations of serum iron (SI), transferrin saturation (TS), ferritin, soluble transferrin receptor (sTfR), and erythropoietin (EPO). The tissue nonheme iron concentrations were measured in the liver, spleen, bone marrow, kidney, heart, gastrocnemius, duodenal epithelium, lung, pallium, cerebellum, hippocampus, and striatum. Hepatic hepcidin expression was detected by real-time PCR analysis. The synthesis of ferroportin 1 (FPN1) in the liver, spleen, kidney, and bone marrow was determined by Western blot analysis. The synthesis of duodenal cytochrome B561 (DcytB), divalent metal transporter 1 (DMT1), FPN1, hephaestin (HP) in the duodenal epithelium was also measured by Western blot analysis. The results showed that the RBC, Hb, and Hct in male rats were higher than those in female rats. The SI and plasma TS levels were lower in male rats than in female rats. The levels of serum ferritin and sTfR were higher in male rats than in female rats. The EPO levels in male rats were lower than that in female rats. The nonheme iron contents in the liver, spleen, bone marrow, and kidney in male rats were also lower (56.7, 73.2, 60.6, and 61.4 % of female rats, respectively). Nonheme iron concentrations in the heart, gastrocnemius, duodenal epithelium, lung, and brain were similar in rats of both sexes. A moderate decrease in hepatic hepcidin mRNA content was also observed in male rats (to 56.0 % of female rats). The levels of FPN1 protein in the liver, spleen, and kidney were higher in male rats than in female rats. There was no significant change in FPN1 expression in bone marrow. Significant difference was also not found in DcytB, DMT1, FPN1, and HP protein levels in the duodenal epithelium between male and female rats. These data suggest that iron is distributed differently in male and female rats. This difference in iron distribution may be associated with the difference in the hepcidin level. PMID:24962641

Kong, Wei-Na; Niu, Qiao-Man; Ge, Lan; Zhang, Nan; Yan, Shao-Feng; Chen, Wei-Bin; Chang, Yan-Zhong; Zhao, Shu-E

2014-08-01

333

Regulation of tissue LC-PUFA contents, ?6 fatty acyl desaturase (FADS2) gene expression and the methylation of the putative FADS2 gene promoter by different dietary fatty acid profiles in Japanese seabass (Lateolabrax japonicus).  

PubMed

The present study was conducted to evaluate the influences of different dietary fatty acid profiles on the tissue content and biosynthesis of LC-PUFA in a euryhaline species Japanese seabass reared in seawater. Six diets were prepared, each with a characteristic fatty acid: Diet PA: Palmitic acid (C16:0); Diet SA: Stearic acid (C18:0); Diet OA: Oleic acid (C18:1n-9); Diet LNA: ?-linolenic acid (C18:3n-3); Diet N-3 LC-PUFA: n-3 LC-PUFA (DHA+EPA); Diet FO: the fish oil control. A 10-week feeding trial was conducted using juvenile fish (29.53 ± 0.86 g). The results showed that Japanese seabass had limited capacity to synthesize LC-PUFA and fish fed PA, SA, OA and LNA showed significantly lower tissue n-3 LC-PUFA contents compared to fish fed N-3 LC-PUFA and FO. The putative gene promoter and full-length cDNA of FADS2 was cloned and characterized. The protein sequence was confirmed to be homologous to FADS2s of marine teleosts and possessed all the characteristic features of microsomal fatty acid desaturases. The FADS2 transcript levels in liver of fish fed N-3 LC-PUFA and FO were significantly lower than those in fish fed other diets except LNA while Diet PA significantly up-regulated the FADS2 gene expression compared to Diet LNA, N-3 LC-PUFA and FO. Inversely, fish fed N-3 LC-PUFA and FO showed significantly higher promoter methylation rates of FADS2 gene compared to fish fed the LC-PUFA deficient diets. These results suggested that Japanese seabass had low LC-PUFA synthesis capacity and LC-PUFA deficient diets caused significantly reduced tissue n-3 LC-PUFA contents. The liver gene expression of FADS2 was up-regulated in groups enriched in C16:0, C18:0 and C18:1n-9 respectively but not in the group enriched in C18:3n-3 compared to groups with high n-3 LC-PUFA contents. The FADS2 gene expression regulated by dietary fatty acids was significantly negatively correlated with the methylation rate of putative FADS2 gene promoter. PMID:24498178

Xu, Houguo; Dong, Xiaojing; Ai, Qinghui; Mai, Kangsen; Xu, Wei; Zhang, Yanjiao; Zuo, Rantao

2014-01-01

334

Iron metabolism, free radicals, and oxidative injury  

Microsoft Academic Search

Iron has the capacity to accept and donate electrons readily. This capability makes it physiologically essential, as a useful component of cytochromes and oxygen-binding molecules. However, iron is also biochemically dangerous; it can damage tissues by catalyzing the conversion of hydrogen peroxide to free-radical ions that attack cellular membranes, protein and DNA. This threat is reduced in the healthy state

J Emerit; C Beaumont; F Trivin

2001-01-01

335

The effect of iron dilution on strength of nickel\\/steel and Monel\\/steel welds  

Microsoft Academic Search

The weld strength, as a function of iron content, for nickel\\/steel and Monel\\/steel welds was determined. Samples were prepared using a Gas Metal Arc (GMAW) automatic process to weld steel plate together with nickel or Monel to produce a range of iron contents typical of weld compositions. Tensile specimens of each iron content were tested to obtain strength and ductility

S. L. Fout; S. D. Wamsley

1983-01-01

336

Iron Test  

MedlinePLUS

... and Kowdley, K. (2012). Review Article: The Iron Overload Syndromes. Medscape Reference from Aliment Pharmacol Ther . V35 (8):876-893. [On-line information]. Available online at http://www.medscape.com/viewarticle/ ...

337

Prediction of fatty acids content in pig adipose tissue by near infrared spectroscopy: at-line versus in-situ analysis.  

PubMed

A handheld micro-electro-mechanical system (MEMS) based spectrometer working in the near infrared region (NIR) (1600-2400nm) was evaluated for in-situ and non-destructive prediction of main fatty acids in Iberian pig (IP) carcasses. 110 IP carcasses were measured. Performance of the instrument was compared with at-line high-resolution NIRS monochromators working in two analysis modes: melted fat samples (transflectance cups) and intact adipose tissues (interactance fiber optic). Standard Error of Prediction (SEP) values obtained on the MEMS-NIRS device were: 0.68% (stearic), 1.30% (oleic), 0.55% (linoleic) and 1% (palmitic), explaining a variability of 83%, 84%, 81% and 78%, respectively. As expected, this represented a loss of predictive capability in comparison to at-line models, even with the same spectral characteristics as on the handheld device. However, the estimated total errors were at the same level for gas chromatography and NIRS analysis. This indicates that the MEMS-NIRS in-situ analysis of each individual carcass provides a cost-effective and real-time quality control system with suitable accuracy. PMID:23793086

Zamora-Rojas, E; Garrido-Varo, A; De Pedro-Sanz, E; Guerrero-Ginel, J E; Pérez-Marín, D

2013-11-01

338

Iron Translocation II. Citrate/Iron Ratios in Plant Stem Exudates  

PubMed Central

Stem exudates of sunflower, soybean, cucumber, and tomato were analyzed for citrate and iron content. Generally, the lowest iron treatments given at decapitation were associated with lowest citrate levels in the exudate and intermediate treatments with the highest citrate levels. Citrate reached 6.2 × 10?4 m in sunflower exudate. 7.3 × 10?4 m in soybean, 9.4 × 10?4 m in cucumber, and 1.8 × 10?4 m in tomato. Some of these values represent a doubling or tripling of citrate when compared to the lowest ones obtained. High Fe depressed the citrate content of exudate in some cases. As iron was raised in the nutrient, the increases of iron in the exudate were proportionately greater than those of citrate. The highest Fe treatments led to exaggerated uptake of iron by sunflower. In some cases iron was translocated in molar excess of citrate. A time-response experiment with tomato showed a rapid flooding of iron into the roots but a relatively slow release of iron into xylem exudate. Similar electrophoretic patterns of iron were obtained despite changes in citrate and iron with time. Exudates from sunflower, cucumber, and tomato gave iron concentrations in the position of iron-citrate. Images

Tiffin, Lee O.

1966-01-01

339

The iron chelator pyridoxal isonicotinoyl hydrazone (PIH) and its analogues prevent damage to 2-deoxyribose mediated by ferric iron plus ascorbate  

Microsoft Academic Search

Iron chelating agents are essential for treating iron overload in diseases such as ?-thalassemia and are potentially useful for therapy in non-iron overload conditions, including free radical mediated tissue injury. Deferoxamine (DFO), the only drug available for iron chelation therapy, has a number of disadvantages (e.g., lack of intestinal absorption and high cost). The tridentate chelator pyridoxal isonicotinoyl hydrazone (PIH)

Marcelo Hermes-Lima; Prem Ponka; Herbert M. Schulman

2000-01-01

340

Iron control in zinc pressure leach processes  

NASA Astrophysics Data System (ADS)

The occurrence of zinc in sulfide ore deposits is generally accompanied by various iron minerals. Hence, even the most efficient concentrators generally produce a zinc concentrate with significant iron content. The efficient recovery of zinc metal from zinc concentrates requires the rejection of iron residue in a form that minimizes the zinc entrainment. Careful control of the iron precipitation step is important, so that the iron residue produced is amenable to efficient liquid-solid separation in order to obtain high zinc recoveries. In hydrometallurgical zinc processes, the coprecipitation of minor impurities along with iron precipitation is also important in producing zinc-sulfate solution from which high-purity zinc cathode can be electrowon. The integration of Dynatec’s zinc pressure leach process with existing roast-leach-electrowin plants employing various methods of iron rejection is briefly described in this article, along with the application of two-stage pressure leaching in stand-alone processes.

Buban, K. R.; Collins, M. J.; Masters, I. M.

1999-12-01

341

Effect of Vitamin A Deficiency on Iron Bioavailability  

Microsoft Academic Search

Background: Vitamin A deficiency alters iron status leading to an iron overload in tissues; however, the mechanism of this interaction is poorly understood. The present study aimed to assess the effect of vitamin A deficiency on iron bioavailability and utilization in rats. Methods: Animals were divided into three groups of six rats each that were fed AIN-93G diet (control group),

A. Mehdad; E. M. A. Siqueira; S. F. Arruda

2010-01-01

342

Iron Overload - A Growing Nutritional Disorder from Dietary Excess  

Microsoft Academic Search

overload is alarming and the implications of iron overload in a number of equine diseases are growing. Iron is an essential element in most biological systems, the most well known being hemoglobin and myoglobin. Iron is the basis of the heme component of the red blood cell that binds oxygen and allows it to be carried to the tissues. (Jackson,

Amberlee Ficociello

343

Direct profiling of phytochemicals in tulip tissues and in vivo monitoring of the change of carbohydrate content in tulip bulbs by probe electrospray ionization mass spectrometry.  

PubMed

Probe electrospray ionization (PESI) is a recently developed ESI-based ionization technique which generates electrospray from the tip of a solid needle. In this study, we have applied PESI interfaced with a time of flight mass spectrometer (TOF-MS) for direct profiling of phytochemicals in a section of a tulip bulb in different regions, including basal plate, outer and inner rims of scale, flower bud and foliage leaves. Different parts of tulip petals and leaves have also been investigated. Carbohydrates, amino acids and other phytochemicals were detected. A series of in vivo PESI-MS experiments were carried out on the second outermost scales of four living tulip bulbs to monitoring the change of carbohydrate content during the first week of initial growth. The breakdown of carbohydrates was observed which was in accordance with previous reports achieved by other techniques. This study has indicated that PESI-MS can be used for rapid and direct analysis of phytochemicals in living biological systems with advantages of low sample consumption and little sample preparation. Therefore, PESI-MS can be a new choice for direct analysis/profiling of bioactive compounds or monitoring metabolic changes in living biological systems. PMID:19815427

Yu, Zhan; Chen, Lee Chuin; Suzuki, Hiroaki; Ariyada, Osamu; Erra-Balsells, Rosa; Nonami, Hiroshi; Hiraoka, Kenzo

2009-12-01

344

Decreased arachidonic acid content and metabolism in tissues of NZB/W F1 females fed a diet containing 0. 45% dehydroisoandrosterone (DHA)  

SciTech Connect

A diet containing 0.45% DHA fed to NZB/W mice, a model of systemic lupus erythematosus, delays the time of onset, improves survival and decreases the formation of antibodies to ds-DNA. Essential fatty acid-deficient diets or inclusion of eicosapentaenoic acid have similar beneficial effects and led them to investigate arachidonic acid metabolism in response to feeding DHA. The arachidonic acid content of plasma cholesteryl ester decreased from 37.4 +/- 2.2 to 28.2 +/- 1.3 mg%. In total liver phospholipid the value decreased from 18.1 +/- 0.52 to 13.7 +/- 1.3 mg%, in total kidney phospholipid the value decreased from 24.10 +/- 0.87 to 20.7 +/- 0.32 mg% and in resident peritoneal macrophages the value decreased from 15.4 +/- 4.6 to 3.6 +/- 1.4 mg%. The metabolism of exogenous (1-/sup 14/C)arachidonic acid by resident peritoneal macrophages in response to Zymosan stimulation for 2 hr was examined by extraction of metabolites and separation by HPLC. Cells isolated from DHA-fed animals produced less PGE2 than controls, yet similar amounts of 6-keto PGF1..cap alpha.. were produced. Arachidonic acid metabolites have significant effects on the immune system and may be a mechanism involved in the benefits obtained by inclusion of DHA in the diet.

Matsunaga, A.; Cottam, G.L.

1987-05-01

345

SreA-mediated iron regulation in Aspergillus fumigatus  

PubMed Central

Aspergillus fumigatus, the most common airborne fungal pathogen of humans, employs two high-affinity iron uptake systems: iron uptake mediated by the extracellular siderophore triacetylfusarinine C and reductive iron assimilation. Furthermore, A. fumigatus utilizes two intracellular siderophores, ferricrocin and hydroxyferricrocin, to store iron. Siderophore biosynthesis, which is essential for virulence, is repressed by iron. Here we show that this control is mediated by the GATA factor SreA. During iron-replete conditions, SreA deficiency partially derepressed synthesis of triacetylfusarinine C and uptake of iron resulting in increased cellular accumulation of both iron and ferricrocin. Genome-wide DNA microarray analysis identified 49 genes that are repressed by iron in an SreA-dependent manner. This gene set, termed SreA regulon, includes all known genes involved in iron acquisition, putative novel siderophore biosynthetic genes, and also genes not directly linked to iron metabolism. SreA deficiency also caused upregulation of iron-dependent and antioxidative pathways, probably due to the increased iron content and iron-mediated oxidative stress. Consistently, the sreA disruption mutant displayed increased sensitivity to iron, menadion and phleomycin but retained wild-type virulence in a mouse model. As all detrimental effects of sreA disruption are restricted to iron-replete conditions these data underscore that A. fumigatus faces iron-depleted conditions during infection.

Schrettl, Markus; Kim, H Stanley; Eisendle, Martin; Kragl, Claudia; Nierman, William C; Heinekamp, Thorsten; Werner, Ernst R; Jacobsen, Ilse; Illmer, Paul; Yi, Hyojeong; Brakhage, Axel A; Haas, Hubertus

2008-01-01

346

Effect of iron limitation on cells of the diatom  

Microsoft Academic Search

The response of the Baltic diatom Cyclotella meneghiniana to iron deficiency was examined. The following growth parameters were measured: cell number, chlorophyll a and protein content. The results demonstrate the ability of this diatom to grow well with minimal iron availability; however, the rate of growth fell markedly at the lowest iron(III) concentration. The results of spectrophotometric chlorophyll a measurements

Jolanta Lewandowska; Alicja Kosakowska

347

Synthesis of yttrium iron garnet precursor particles by homogeneous precipitation  

Microsoft Academic Search

Yttrium iron garnet (YIG) precursor particles were obtained by homogeneous precipitation in a nitrate salt solution by a reaction involving the thermal decomposition of urea. Chemical analysis indicated that solid phases were initially precipitated with sequential iron ion content. The precipitate formed was an amorphous mixed iron oxide phase. The complex composition and the thermal decomposition of the precipitate were

Y. S. Ahn; M. H. Han; C. O. Kim

1996-01-01

348

Thermosensitive liposomes entrapping iron oxide nanoparticles for controllable drug release  

Microsoft Academic Search

Iron oxide nanoparticles can serve as a heating source upon alternative magnetic field (AMF) exposure. Iron oxide nanoparticles can be mixed with thermosensitive nanovehicles for hyperthermia-induced drug release, yet such a design and mechanism may not be suitable for controllable drug release applications in which the tissues are susceptible to environmental temperature change such as brain tissue. In the present

Lin-Ai Tai; Pi-Ju Tsai; Yu-Chao Wang; Yu-Jing Wang; Leu-Wei Lo; Chung-Shi Yang

2009-01-01

349

Inhibited PTHLH downstream leukocyte adhesion-mediated protein amino acid N-linked glycosylation coupling Notch and JAK-STAT cascade to iron-sulfur cluster assembly-induced aging network in no-tumor hepatitis/cirrhotic tissues (HBV or HCV infection) by systems-theoretical analysis.  

PubMed

We analyzed the different biological processes and occurrence numbers between low expression inhibited PTHLH downstream-mediated aging gene ontology (GO) network of no-tumor hepatitis/cirrhotic tissues (HBV or HCV infection) and the corresponding high expression (fold change ?2) inhibited GO network of human hepatocellular carcinoma (HCC). Inhibited PTHLH downstream-mediated aging network consisted of aging, branched chain family amino acid biosynthesis, cellular metabolism, cholesterol biosynthesis, coupled to cyclic nucleotide second messenger, cytolysis, 'de novo' GDP-l-fucose biosynthesis, detection of mechanical stimulus, glucose homeostasis, G-protein signaling, leukocyte adhesion, iron-sulfur cluster assembly, JAK-STAT cascade, Notch signaling pathway, nucleotide-sugar metabolism, peptidyl-tyrosine sulfation, protein amino acid N-linked glycosylation, protein amino acid phosphorylation, response to drug, rRNA processing, translational initiation, ubiquitin-dependent protein catabolism, homophilic cell adhesion in no-tumor hepatitis/cirrhotic tissues. We proposed inhibited PTHLH downstream leukocyte adhesion-mediated protein amino acid N-linked glycosylation coupling Notch and JAK-STAT cascade to iron-sulfur cluster assembly-induced aging network. Our hypothesis was verified by the same inhibited PTHLH downstream-mediated aging GO network in no-tumor hepatitis/cirrhotic tissues with the corresponding activated GO network of HCC, or the different with the corresponding activated GO network of no-tumor hepatitis/cirrhotic tissues. Inhibited PTHLH downstream leukocyte adhesion-mediated protein amino acid N-linked glycosylation coupling Notch and JAK-STAT cascade to iron-sulfur cluster assembly-induced aging network included TSTA3, ALK, CIAO1, NOTCH3 in no-tumor hepatitis/cirrhotic tissues from the GEO data set using gene regulatory network inference method and our programming. PMID:22955522

Wang, Lin; Huang, Juxiang; Jiang, Minghu; Lin, Hong; Qi, Lianxiu; Diao, Haizhen

2012-10-01

350

Iron Chelation Therapy  

MedlinePLUS

... iron overload. What actually happens to cause iron overload? With each red blood cell transfusion, your body ... is deposited. What are the symptoms of iron overload? Early on, iron overload can cause no symptoms, ...

351

Fractionation of iron isotopes in mantle peridotites  

NASA Astrophysics Data System (ADS)

A current subject of debate is whether or not stable isotopes of the transition elements can be fractionated at high temperatures by inorganic process. In the case of iron, recent studies (Zhu et al., 2002, EPSL v.200, 1-2, 47-62) have indicated that there are significant isotopic fractionations between mantle minerals that have equilibrated at high temperatures (>900^oC). We present iron isotope data for minerals from mantle peridotites representing different tectonic settings, which span a range in source fertility, composition, and oxygen fugacity. Iron isotope measurements were carried out by MC-ICP-MS following sample dissolution and iron extraction by anionic exchange chromatography. Iron isotope compositions are reported relative to IRMM-14; external reproducibility was 0.13 ppm for 57Fe/54Fe and 0.14 ppm for 57Fe/56Fe (2 S.D.). We observe consistent isotopic fractionations between olivine, orthopyroxene and clinopyroxene in all peridotites. The isotopic compositions of the olivines are ˜ 0.20 ppm (57Fe/54Fe) lighter than those of clinopyroxene and orthopyroxene (which are the same within error) and are consistent with the results of Zhu et al. (2002). Spinels show extreme isotopic variations, with a range of over 1.70 ppm in 57Fe/54Fe. The lightest isotopic compositions (-0.50 ppm 57Fe/54Fe) are observed in spinels from island-arc peridotites, whereas the heaviest are for spinels from Cameroon Line xenoliths (+0.95 to +1.20 ppm 57Fe/54Fe). The spinel iron isotope compositions do not show any correlations or systematic offsets with respect to the iron isotope compositions of any of the other co-existing minerals. However, the spinel iron isotope signatures show positive correlations with alumina content and negative correlations with total iron content and the ferric iron/total iron ratio of the spinels (calculated by stoichiometry assuming complete site occupancy from electron microprobe data). A possible interpretation is that iron isotope fractionation is controlled by spinel chemistry and the predominant oxidation state of the iron incorporated. Changes in spinel iron isotope composition could therefore be a sensitive record for changes in oxygen fugacity and the incorporation of water into the mantle. To test this hypothesis, further iron isotope analyses will be undertaken on minerals from well-characterised mantle xenoliths for which both the ferric/total iron contents and water contents have already been determined (by Mossbauer spectroscopy and Fourier transform infrared spectrometry, respectively; Peslier et al., 2002, EPSL, v. 201, 1, 69-86).

Williams, H.; Peslier, A.; Teutsch, N.; Levasseur, S.; Halliday, A.

2003-04-01

352

Ironic Processes of Mental Control  

Microsoft Academic Search

A theory of ironic processes of mental control is proposed to account for the intentional and counterintentional effects that result from efforts at self-control of mental states. The theory holds that an attempt to control the mind introduces 2 processes: (a) an operating process that promotes the intended change by searching for mental contents consistent with the intended state and

Daniel M. Wegner

1994-01-01

353

Lack of correlation between iron stores and plasma lactoferrin concentration.  

PubMed

Plasma lactoferrin concentration and indices of iron nutrition including P-Ferritin, P-iron, total iron binding capacity and percentage saturation were measured in 75 otherwise normal females. This was done in order to evaluate previous reports that neutrophil lactoferrin content was altered by variations in iron storage status. Since P-Lactoferrin is derived from and hence reflects neutrophil lactoferrin content it would seem reasonable to assume that P-Lactoferrin would vary in accordance with iron stores. However, there was no statistically significant difference in P-Lactoferrin concentration between iron deficient subjects and those who were iron replete. Furthermore, there was no statistically significant correlation between any iron related parameter and P-Lactoferrin concentration. PMID:3952460

Baynes, R D; Bezwoda, W R; Derman, D P; Khan, Q; Mansoor, N

1986-01-01

354

Iron and infection  

Microsoft Academic Search

Iron and infection. Intravenous iron therapy maintains iron stores and decreases erythropoietin demand in patients undergoing regular dialysis therapy. Microbiology studies show a close relationship between the availability of iron and bacterial virulence. Iron is also an essential requirement of bacteria for multiplication in the host. Therefore, clinical conditions associated with iron excess in the host may increase the risk

SANDA I. PATRUTA; WALTER H. HORL

1999-01-01

355

When is iron overload deleterious, and when and how should iron chelation therapy be administered in myelodysplastic syndromes?  

PubMed

Iron overload in MDS starts even before patients become red-blood cell transfusion dependent, because disease-associated ineffective erythropoiesis suppresses hepcidin production in the liver and thus causes unrestrained iron absorption in the duodenum. However, the main cause of iron overload is regular transfusion therapy, which in MDS is associated with a risk of unclear magnitude for iron-related complications. Iron deposition in tissues can now be detected with non-invasive techniques such as T2* MRI. Iron toxicity in MDS may not only depend on the degree of tissue iron accumulation but also on the extent of chronic exposure to non-transferrin-bound iron (NTBI), including labile plasma iron (LPI) and intracellular labile iron pools, which increase the level of oxidative stress. Iron chelation therapy (ICT) can rapidly lower NTBI and LPI and more slowly mobilizes tissue iron stores. Further studies, including the ongoing TELESTO controlled trial, will more clearly define the role of ICT in MDS, including any effect on specific morbidities or mortality in the MDS setting. PMID:24507819

Steensma, David P; Gattermann, Norbert

2013-12-01

356

Thermodynamics of carbon in nickel, iron-nickel and iron-chromium-nickel alloys  

Microsoft Academic Search

Iron-nickel alloys with 8 and 16 wt pct nickel and iron-chromium-nickel alloys with 8 pct nickel and chromium contents in\\u000a the range of 2 to 22 pct were equilibrated with iron and nickel in flowing CH4-H2 gas mixtures and in sealed capsules under partial vacuum at temperatures between 700 and 1060?C. Carbon activities in these\\u000a alloys were established from the

K. Natesan; T. F. Kassner

1973-01-01

357

Ferritin Mutants of Escherichia coli Are Iron Deficient and Growth Impaired, and fur Mutants are Iron Deficient  

PubMed Central

Escherichia coli contains at least two iron storage proteins, a ferritin (FtnA) and a bacterioferritin (Bfr). To investigate their specific functions, the corresponding genes (ftnA and bfr) were inactivated by replacing the chromosomal ftnA and bfr genes with disrupted derivatives containing antibiotic resistance cassettes in place of internal segments of the corresponding coding regions. Single mutants (ftnA::spc and bfr::kan) and a double mutant (ftnA::spc bfr::kan) were generated and confirmed by Western and Southern blot analyses. The iron contents of the parental strain (W3110) and the bfr mutant increased by 1.5- to 2-fold during the transition from logarithmic to stationary phase in iron-rich media, whereas the iron contents of the ftnA and ftnA bfr mutants remained unchanged. The ftnA and ftnA bfr mutants were growth impaired in iron-deficient media, but this was apparent only after the mutant and parental strains had been precultured in iron-rich media. Surprisingly, ferric iron uptake regulation (fur) mutants also had very low iron contents (2.5-fold less iron than Fur+ strains) despite constitutive expression of the iron acquisition systems. The iron deficiencies of the ftnA and fur mutants were confirmed by Mössbauer spectroscopy, which further showed that the low iron contents of ftnA mutants are due to a lack of magnetically ordered ferric iron clusters likely to correspond to FtnA iron cores. In combination with the fur mutation, ftnA and bfr mutations produced an enhanced sensitivity to hydroperoxides, presumably due to an increase in production of “reactive ferrous iron.” It is concluded that FtnA acts as an iron store accommodating up to 50% of the cellular iron during postexponential growth in iron-rich media and providing a source of iron that partially compensates for iron deficiency during iron-restricted growth. In addition to repressing the iron acquisition systems, Fur appears to regulate the demand for iron, probably by controlling the expression of iron-containing proteins. The role of Bfr remains unclear.

Abdul-Tehrani, Hossein; Hudson, Aaron J.; Chang, Yung-Sheng; Timms, Andrew R.; Hawkins, Chris; Williams, John M.; Harrison, Pauline M.; Guest, John R.; Andrews, Simon C.

1999-01-01

358

Application of adsorptive stripping voltammetry to the speciation and determination of iron(III) and total iron in wines.  

PubMed

An analytical procedure for the determination of iron(III) and total iron in wines based on adsorptive stripping voltammetry is described. Iron(III) was determined by using Solochrome Violet Red as chelating agent while catechol was used for the determination of the total iron content. Each chelate was adsorbed on the hanging mercury electrode and the reduction current of the accumulated chelate was measured. The results obtained from the application of this procedure to wine samples are discussed. PMID:2757234

Wang, J; Mannino, S

1989-05-01

359

Extracellular Iron Biomineralization by Photoautotrophic Iron-Oxidizing Bacteria ? †  

PubMed Central

Iron oxidation at neutral pH by the phototrophic anaerobic iron-oxidizing bacterium Rhodobacter sp. strain SW2 leads to the formation of iron-rich minerals. These minerals consist mainly of nano-goethite (?-FeOOH), which precipitates exclusively outside cells, mostly on polymer fibers emerging from the cells. Scanning transmission X-ray microscopy analyses performed at the C K-edge suggest that these fibers are composed of a mixture of lipids and polysaccharides or of lipopolysaccharides. The iron and the organic carbon contents of these fibers are linearly correlated at the 25-nm scale, which in addition to their texture suggests that these fibers act as a template for mineral precipitation, followed by limited crystal growth. Moreover, we evidence a gradient of the iron oxidation state along the mineralized fibers at the submicrometer scale. Fe minerals on these fibers contain a higher proportion of Fe(III) at cell contact, and the proportion of Fe(II) increases at a distance from the cells. All together, these results demonstrate the primordial role of organic polymers in iron biomineralization and provide first evidence for the existence of a redox gradient around these nonencrusting, Fe-oxidizing bacteria.

Miot, Jennyfer; Benzerara, Karim; Obst, Martin; Kappler, Andreas; Hegler, Florian; Schadler, Sebastian; Bouchez, Camille; Guyot, Francois; Morin, Guillaume

2009-01-01

360

Iron requirements of infants and toddlers.  

PubMed

Iron deficiency (ID) is the most common micronutrient deficiency worldwide and young children are a special risk group because their rapid growth leads to high iron requirements. Risk factors associated with a higher prevalence of ID anemia (IDA) include low birth weight, high cow's-milk intake, low intake of iron-rich complementary foods, low socioeconomic status, and immigrant status. The aim of this position paper was to review the field and provide recommendations regarding iron requirements in infants and toddlers, including those of moderately or marginally low birth weight. There is no evidence that iron supplementation of pregnant women improves iron status in their offspring in a European setting. Delayed cord clamping reduces the risk of ID. There is insufficient evidence to support general iron supplementation of healthy European infants and toddlers of normal birth weight. Formula-fed infants up to 6 months of age should receive iron-fortified infant formula, with an iron content of 4 to 8 mg/L (0.6-1.2 mg(-1) · kg(-1) · day(-1)). Marginally low-birth-weight infants (2000-2500 g) should receive iron supplements of 1-2 mg(-1) · kg(-1) · day(-1). Follow-on formulas should be iron-fortified; however, there is not enough evidence to determine the optimal iron concentration in follow-on formula. From the age of 6 months, all infants and toddlers should receive iron-rich (complementary) foods, including meat products and/or iron-fortified foods. Unmodified cow's milk should not be fed as the main milk drink to infants before the age of 12 months and intake should be limited to <500 mL/day in toddlers. It is important to ensure that this dietary advice reaches high-risk groups such as socioeconomically disadvantaged families and immigrant families. PMID:24135983

Domellöf, Magnus; Braegger, Christian; Campoy, Cristina; Colomb, Virginie; Decsi, Tamas; Fewtrell, Mary; Hojsak, Iva; Mihatsch, Walter; Molgaard, Christian; Shamir, Raanan; Turck, Dominique; van Goudoever, Johannes

2014-01-01

361

Enhanced and selective delivery of enzyme therapy to 9L-glioma tumor via magnetic targeting of PEG-modified, ?-glucosidase-conjugated iron oxide nanoparticles  

PubMed Central

The stability of enzyme-conjugated magnetic iron oxide nanoparticles in plasma is of great importance for in vivo delivery of the conjugated enzyme. In this study, ?-glucosidase was conjugated on aminated magnetic iron oxide nanoparticles using the glutaraldehyde method (?-Glu-MNP), and further PEGylated via N-hydroxysuccinimide chemistry. The PEG-modified, ?-glucosidase-immobilized magnetic iron oxide nanoparticles (PEG-?-Glu-MNPs) were characterized by hydrodynamic diameter distribution, zeta potential, Fourier transform infrared spectroscopy, transmission electron microscopy, and a superconducting quantum interference device. The results showed that the multidomain structure and magnetization properties of these nanoparticles were conserved well throughout the synthesis steps, with an expected diameter increase and zeta potential shifts. The Michaelis constant was calculated to evaluate the activity of conjugated ?-glucosidase on the magnetic iron oxide nanoparticles, indicating 73.0% and 65.4% of enzyme activity remaining for ?-Glu-MNP and PEG-?-Glu-MNP, respectively. Both magnetophoretic mobility analysis and pharmacokinetics showed improved in vitro/in vivo stability of PEG-?-Glu-MNP compared with ?-Glu-MNP. In vivo magnetic targeting of PEG-?-Glu-MNP was confirmed by magnetic resonance imaging and electron spin resonance analysis in a mouse model of subcutaneous 9L-glioma. Satisfactory accumulation of PEG-?-Glu-MNP in tumor tissue was successfully achieved, with an iron content of 627±45 nmol Fe/g tissue and ?-glucosidase activity of 32.2±8.0 mU/g tissue.

Zhou, Jie; Zhang, Jian; Gao, Wenxi

2014-01-01

362

Fractionation trends among IVA iron meteorites: contrasts with IIIAB trends  

Microsoft Academic Search

A neutron-activation study of 48 group-IVA irons shows much lower negative slopes on Ir-Au and Ir-As diagrams than observed in the larger magmatic group IIIAB. This difference seems to reflect the tendency of DIr, DAu and DAs to increase with increasing S content. Contents of S and other volatiles are much lower in IVA irons than IIIAB irons. We show

J. T. Wasson; J. W. Richardson

2001-01-01

363

Ferrous iron formation following the co-aggregation of ferric iron and the Alzheimer's disease peptide ?-amyloid (1-42)  

PubMed Central

For decades, a link between increased levels of iron and areas of Alzheimer's disease (AD) pathology has been recognized, including AD lesions comprised of the peptide ?-amyloid (A?). Despite many observations of this association, the relationship between A? and iron is poorly understood. Using X-ray microspectroscopy, X-ray absorption spectroscopy, electron microscopy and spectrophotometric iron(II) quantification techniques, we examine the interaction between A?(1–42) and synthetic iron(III), reminiscent of ferric iron stores in the brain. We report A? to be capable of accumulating iron(III) within amyloid aggregates, with this process resulting in A?-mediated reduction of iron(III) to a redox-active iron(II) phase. Additionally, we show that the presence of aluminium increases the reductive capacity of A?, enabling the redox cycling of the iron. These results demonstrate the ability of A? to accumulate iron, offering an explanation for previously observed local increases in iron concentration associated with AD lesions. Furthermore, the ability of iron to form redox-active iron phases from ferric precursors provides an origin both for the redox-active iron previously witnessed in AD tissue, and the increased levels of oxidative stress characteristic of AD. These interactions between A? and iron deliver valuable insights into the process of AD progression, which may ultimately provide targets for disease therapies.

Everett, J.; Cespedes, E.; Shelford, L. R.; Exley, C.; Collingwood, J. F.; Dobson, J.; van der Laan, G.; Jenkins, C. A.; Arenholz, E.; Telling, N. D.

2014-01-01

364

Ferrous iron formation following the co-aggregation of ferric iron and the Alzheimer's disease peptide ?-amyloid (1-42).  

PubMed

For decades, a link between increased levels of iron and areas of Alzheimer's disease (AD) pathology has been recognized, including AD lesions comprised of the peptide ?-amyloid (A?). Despite many observations of this association, the relationship between A? and iron is poorly understood. Using X-ray microspectroscopy, X-ray absorption spectroscopy, electron microscopy and spectrophotometric iron(II) quantification techniques, we examine the interaction between A?(1-42) and synthetic iron(III), reminiscent of ferric iron stores in the brain. We report A? to be capable of accumulating iron(III) within amyloid aggregates, with this process resulting in A?-mediated reduction of iron(III) to a redox-active iron(II) phase. Additionally, we show that the presence of aluminium increases the reductive capacity of A?, enabling the redox cycling of the iron. These results demonstrate the ability of A? to accumulate iron, offering an explanation for previously observed local increases in iron concentration associated with AD lesions. Furthermore, the ability of iron to form redox-active iron phases from ferric precursors provides an origin both for the redox-active iron previously witnessed in AD tissue, and the increased levels of oxidative stress characteristic of AD. These interactions between A? and iron deliver valuable insights into the process of AD progression, which may ultimately provide targets for disease therapies. PMID:24671940

Everett, J; Céspedes, E; Shelford, L R; Exley, C; Collingwood, J F; Dobson, J; van der Laan, G; Jenkins, C A; Arenholz, E; Telling, N D

2014-06-01

365

Serum ferritin and iron uptake by peripheral blood leucocytes in patients with active rheumatoid arthritis  

Microsoft Academic Search

Summary Rheumatoid arthritis is a systemic disease in which anaemia is common. The origin of the anaemia is usually multifactorial. Iron deficiency, a defect of release of iron from the reticulo-endothelial system1 is discussed. Ferritin content of monocytes, lymphocytes and polymorphes is found altered and mostly elevated in monocytes affected by serum iron deficiency. In all cell types iron uptake

F. Singer; M. Reinthaler

1982-01-01

366

Chemical Classification of Iron Meteorites: XII. New Members of the Magmatic Groups  

Microsoft Academic Search

Data are reported for thirty iron meteorites that are members of the magmatic groups, for three main group pallasites, one anomalous mesosiderite, and for three ungrouped irons and an ungrouped pallasite that are similar to IIIAB irons in their Ni, Ga, and Ge contents. The set includes four observed falls (11% of iron falls) Ban Rong Du, Chisenga, Nyaung and

John T. Wasson; Byeon-Gak Choi; Eric A. Jerde; Finn Ulff-Møller

1998-01-01

367

Mesothelioma and Analysis of Tissue Fiber Content  

Microsoft Academic Search

\\u000a The strong relationship between mesothelioma and asbestos exposure is well established. The analysis of lung asbestos burden\\u000a by light and electron microscopy assisted to understand the increased incidence of mesothelioma in asbestos mining and consuming\\u000a nations.\\u000a \\u000a \\u000a The data on the occupational exposure to asbestos are important information for the purpose of compensation of occupational\\u000a disease No. 4105 (asbestos-associated mesothelioma) in

Volker Neumann; Stefan Löseke; Andrea Tannapfel

368

Fetal iron status regulates maternal iron metabolism during pregnancy in the rat.  

PubMed

Iron metabolism during pregnancy is biased toward maintaining the fetal supply, even at the cost of anemia in the mother. The mechanisms regulating this are not well understood. Here, we examine iron deficiency and supplementation on the hierarchy of iron supply and the gene expression of proteins that regulate iron metabolism in the rat. Dams were fed iron-deficient diets for 4 wk, mated, and either continued on the deficient diet or an iron-supplemented diet during either the first half or the second half of their pregnancy. A control group was maintained on normal iron throughout. They were killed at 0.5, 12.5, or 21.5 days of gestation, and tissues and blood samples were collected. Deficiency and supplementation had differential effects on maternal and fetal hematocrit and liver iron levels. From early in pregnancy, a hierarchy of iron supply is established benefiting the fetus to the detriment of the mother. Transferrin receptor, transferrin receptor 2, and hepcidin mRNA expression were regulated by both iron deficiency and supplementation. Expression patterns showed both organ and supplementation protocol dependence. Further analysis indicated that iron levels in the fetal, and not maternal, liver regulate the expression of liver transferrin receptor and hepcidin expression in the mother. PMID:19176888

Gambling, Lorraine; Czopek, Alicja; Andersen, Henriette S; Holtrop, Grietje; Srai, S Kaila S; Krejpcio, Zbigniew; McArdle, Harry J

2009-04-01

369

Iron Biofortification and Homeostasis in Transgenic Cassava Roots Expressing the Algal Iron Assimilatory Gene, FEA1  

PubMed Central

We have engineered the tropical root crop cassava (Manihot esculenta) to express the Chlamydomonas reinhardtii iron assimilatory gene, FEA1, in its storage roots with the objective of enhancing the root nutritional qualities. Iron levels in mature cassava storage roots were increased from 10 to 36?ppm in the highest iron accumulating transgenic lines. These iron levels are sufficient to meet the minimum daily requirement for iron in a 500?g meal. Significantly, the expression of the FEA1 gene in storage roots did not alter iron levels in leaves. Transgenic plants also had normal levels of zinc in leaves and roots consistent with the specific uptake of ferrous iron mediated by the FEA1 protein. Relative to wild-type plants, fibrous roots of FEA1 expressing plants had reduced Fe (III) chelate reductase activity consistent with the more efficient uptake of iron in the transgenic plants. We also show that multiple cassava genes involved in iron homeostasis have altered tissue-specific patterns of expression in leaves, stems, and roots of transgenic plants consistent with increased iron sink strength in transgenic roots. These results are discussed in terms of strategies for the iron biofortification of plants.

Ihemere, Uzoma E.; Narayanan, Narayanan N.; Sayre, Richard T.

2012-01-01

370

Body iron delocalization: the serious drawback in iron disorders in both developing and developed countries  

PubMed Central

Over 2 billion people in both developing as well as developed countries – over 30% of the world’s population – are anaemic. With the classical preconception that oral iron administration or the intake of foods rich in iron increase haemoglobin concentration and reduce the prevalence of anaemia, specific programs have been designed, but iron supplementations have been less effective than expected. Of note, this hazardous simplification on iron status neglects its distribution in the body. The correct balance of iron, defined iron homeostasis, involves a physiological ratio of iron between tissues/secretions and blood, thus avoiding its delocalization as iron accumulation in tissues/secretions and iron deficiency in blood. Changes in iron status can affect the inflammatory response in multiple ways, particularly in the context of infection, an idea that is worth remembering when considering the value of iron supplementation in areas of the world where infections are highly prevalent. The enhanced availability of free iron can increase susceptibility and severity of microbial and parasitic infections. The discovery of the hepcidin–ferroportin (Fpn) complex, which greatly clarified the enigmatic mechanism that supervises the iron homeostasis, should prompt to a critical review on iron supplementation, ineffective on the expression of the most important proteins of iron metabolism. Therefore, it is imperative to consider new safe and efficient therapeutic interventions to cure iron deficiency (ID) and ID anaemia (IDA) associated or not to the inflammation. In this respect, lactoferrin (Lf) is emerging as an important regulator of both iron and inflammatory homeostasis. Oral administration of Lf in subjects suffering of ID and IDA is safe and effective in significantly increasing haematological parameters and contemporary decreasing serum IL-6 levels, thus restoring iron localization through the direct or indirect modulation of hepcidin and ferroportin synthesis. Of note, the nuclear localization of Lf suggests that this molecule may be involved in the transcriptional regulation of some genes of host inflammatory response. We recently also reported that combined administration of oral and intravaginal Lf on ID and IDA pregnant women with preterm delivery threat, significantly increased haematological parameters, reduced IL-6 levels in both serum and cervicovaginal fluid, cervicovaginal prostaglandin PGF2?, and suppressed uterine contractility. Moreover, Lf combined administration blocked further the shortening of cervical length and the increase of foetal fibronectin, thus prolonging the length of pregnancy until the 37th–38th week of gestation. These new Lf functions effective in curing ID and IDA through the restoring of iron and inflammatory homeostasis and in preventing preterm delivery, could have a great relevance in developing countries, where ID and IDA and inflammation-associated anaemia represent the major risk factors of preterm delivery and maternal and neonatal death.

Paesano, R; Natalizi, T; Berlutti, F; Valenti, P

2012-01-01

371

Relaxivity-iron calibration in hepatic iron overload: probing underlying biophysical mechanisms using a Monte Carlo model.  

PubMed

Iron overload is a serious condition for patients with ?-thalassemia, transfusion-dependent sickle cell anemia, and inherited disorders of iron metabolism. MRI is becoming increasingly important in noninvasive quantification of tissue iron, overcoming the drawbacks of traditional techniques (liver biopsy). Effective transverse relaxation rate (1/effective transverse relaxation time) rises linearly with iron while transverse relaxation rate (1/T2) has a curvilinear relationship in human liver. Although recent work has demonstrated clinically valid estimates of human liver iron, the calibration varies with MRI sequence, field strength, iron chelation therapy, and organ imaged, forcing recalibration in patients. To understand and correct these limitations, a thorough understanding of the underlying biophysics is of critical importance. Toward this end, a Monte Carlo-based approach, using human liver as a "model" tissue system, was used to determine the contribution of particle size and distribution on MRI signal relaxation. Relaxivities were determined for hepatic iron concentrations ranging from 0.5 to 40 mg iron per gram dry tissue weight. Model predictions captured the linear and curvilinear relationship of effective transverse relaxation rate and transverse relaxation rate with hepatic iron concentrations, respectively, and were within in vivo confidence bounds; contact or chemical exchange mechanisms were not necessary. A validated and optimized model will aid understanding and quantification of iron-mediated relaxivity in tissues where biopsy is not feasible (heart and spleen). PMID:21337413

Ghugre, Nilesh R; Wood, John C

2011-03-01

372

Studies the alterations of biochemical and mineral contents in bone tissue of mus musculus due to aluminum toxicity and the protective action of desferrioxamine and deferiprone by FTIR, ICP-OES, SEM and XRD techniques  

NASA Astrophysics Data System (ADS)

The present study has attempt to analyze the changes in the biochemical and mineral contents of aluminum intoxicated bone and determine the protective action of desferrioxamine (DFO) and deferiprone (DFP) by using Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), inductively coupled plasma optical emission spectroscopy (ICP-OES), and scanning electron microscopy (SEM) techniques for four groups of animals such as control (Group I), aluminum intoxicated (Group II), Al + DFP (Group III) and Al + DFO + DFP (Group IV) treated groups respectively. The FTIR spectra of the aluminum intoxicated bone showed significant alteration in the biochemical constituents. The bands ratio at I1400/I877 significantly decreased from control to aluminum, but enhanced it by Al + DFP to Al + DFO + DFP treated bone tissue for treatments of 16 weeks. This result suggests that DFO and DFP are the carbonate inhibitor, recovered from chronic growth of bone diseases and pathologies. The alteration of proteins profile indicated by Amide I and Amide II, where peak area values decreased from control to aluminum respectively, but enhanced by treated with DFP (p.o.) and DFO + DFP (i.p.) respectively. The XRD analysis showed a decrease in crystallinity due to aluminum toxicity. Further, the Ca, Mg, and P contents of the aluminum exposed bone were less than those of the control group, and enhanced by treatments with DFO and DFP. The concentrations of trace elements were found by ICP-OES. Therefore, present study suggests that due to aluminum toxicity severe loss of bone minerals, decrease in the biochemical constituents and changes in the surface morphology.

Sivakumar, S.; Khatiwada, Chandra Prasad; Sivasubramanian, J.

373

Iron release from corroded iron pipes in drinking water distribution systems: effect of dissolved oxygen.  

PubMed

Iron release from corroded iron pipes is the principal cause of "colored water" problems in drinking water distribution systems. The corrosion scales present in corroded iron pipes restrict the flow of water, and can also deteriorate the water quality. This research was focused on understanding the effect of dissolved oxygen (DO), a key water quality parameter, on iron release from the old corroded iron pipes. Corrosion scales from 70-year-old galvanized iron pipe were characterized as porous deposits of Fe(III) phases (goethite (alpha-FeOOH), magnetite (Fe(3)O(4)), and maghemite (alpha-Fe(2)O(3))) with a shell-like, dense layer near the top of the scales. High concentrations of readily soluble Fe(II) content was present inside the scales. Iron release from these corroded pipes was investigated for both flow and stagnant water conditions. Our studies confirmed that iron was released to bulk water primarily in the ferrous form. When DO was present in water, higher amounts of iron release was observed during stagnation in comparison to flowing water conditions. Additionally, it was found that increasing the DO concentration in water during stagnation reduced the amount of iron release. Our studies substantiate that increasing the concentration of oxidants in water and maintaining flowing conditions can reduce the amount of iron release from corroded iron pipes. Based on our studies, it is proposed that iron is released from corroded iron pipes by dissolution of corrosion scales, and that the microstructure and composition of corrosion scales are important parameters that can influence the amount of iron released from such systems. PMID:14975659

Sarin, P; Snoeyink, V L; Bebee, J; Jim, K K; Beckett, M A; Kriven, W M; Clement, J A

2004-03-01

374

OPT3 Is a Phloem-Specific Iron Transporter That Is Essential for Systemic Iron Signaling and Redistribution of Iron and Cadmium in Arabidopsis[W][OPEN  

PubMed Central

Iron is essential for both plant growth and human health and nutrition. Knowledge of the signaling mechanisms that communicate iron demand from shoots to roots to regulate iron uptake as well as the transport systems mediating iron partitioning into edible plant tissues is critical for the development of crop biofortification strategies. Here, we report that OPT3, previously classified as an oligopeptide transporter, is a plasma membrane transporter capable of transporting transition ions in vitro. Studies in Arabidopsis thaliana show that OPT3 loads iron into the phloem, facilitates iron recirculation from the xylem to the phloem, and regulates both shoot-to-root iron signaling and iron redistribution from mature to developing tissues. We also uncovered an aspect of crosstalk between iron homeostasis and cadmium partitioning that is mediated by OPT3. Together, these discoveries provide promising avenues for targeted strategies directed at increasing iron while decreasing cadmium density in the edible portions of crops and improving agricultural productivity in iron deficient soils.

Zhai, Zhiyang; Gayomba, Sheena R.; Jung, Ha-il; Vimalakumari, Nanditha K.; Pineros, Miguel; Craft, Eric; Rutzke, Michael A.; Danku, John; Lahner, Brett; Punshon, Tracy; Guerinot, Mary Lou; Salt, David E.; Kochian, Leon V.; Vatamaniuk, Olena K.

2014-01-01

375

The effect of iron dilution on strength of nickel/steel and Monel/steel welds  

SciTech Connect

The weld strength, as a function of iron content, for nickel/steel and Monel/steel welds was determined. Samples were prepared using a Gas Metal Arc (GMAW) automatic process to weld steel plate together with nickel or Monel to produce a range of iron contents typical of weld compositions. Tensile specimens of each iron content were tested to obtain strength and ductility measurements for that weld composition. Data indicate that at iron contents of less than 20% iron in a nickel/steel weld, the weld fails at the weld interface, due to a lack of fusion. Between 20% and 35% iron, the highest iron dilution that could be achieved in a nickel weld, the welds were stronger than the steel base metal. This indicates that a minimum amount of iron dilution (20%) is necessary for good fusion and optimum strength. On the other hand for Monel/steel welds, test results showed that the welds had good strength and integrity between 10% and 27% iron in the weld. Above 35% iron, the welds have less strength and are more brittle. The 35% iron content also corresponds to the iron dilution in Monel welds that has been shown to produce an increase in corrosion rate. This indicates that the iron dilution in Monel welds should be kept below 35% iron to maximize both the strength and corrosion resistance. 2 refs., 6 figs., 3 tabs.

Fout, S.L.; Wamsley, S.D.

1983-03-28

376

Cellular iron metabolism  

Microsoft Academic Search

Cellular iron metabolism. Iron is essential for oxidation-reduction catalysis and bioenergetics, but unless appropriately shielded, iron plays a key role in the formation of toxic oxygen radicals that can attack all biological molecules. Hence, specialized molecules for the acquisition, transport (transferrin), and storage (ferritin) of iron in a soluble nontoxic form have evolved. Delivery of iron to most cells, probably

PREM PONKA

1999-01-01

377

Controversies in iron management  

Microsoft Academic Search

Controversies in iron management.BackgroundIron therapy is required in hemodialysis patients receiving erythropoietic stimulators in order to achieve the target hemoglobin in the most efficient way. While oral iron has been disappointing in this regard, parenteral iron has been widely used, despite a significant incidence of severe side effects when iron dextran is used. The recent availability of a more effective

Allen R. Nissenson; Chaim Charytan

2003-01-01

378

Nutritional iron deficiency  

Microsoft Academic Search

Iron deficiency is one of the leading risk factors for disability and death worldwide, affecting an estimated 2 billion people. Nutritional iron deficiency arises when physiological requirements cannot be met by iron absorption from diet. Dietary iron bioavailability is low in populations consuming monotonous plant-based diets. The high prevalence of iron deficiency in the developing world has substantial health and

Michael B Zimmermann; Richard F Hurrell

2007-01-01

379

Hepatic iron overload and hepatocellular carcinoma.  

PubMed

In recent years it has become increasingly evident that excess body iron may be complicated by the supervention of hepatocellular carcinoma (HCC). Hereditary hemochromatosis (HH) was the first condition in which hepatic iron overload was shown to predispose to the development of HCC. The inherited predisposition to excessive absorption of dietary iron in HH is almost always the result of homozygosity of the C282Y mutation of the HFE gene, which causes inappropriately low secretion of hepcidin. HCC develops in 8-10% of patients with HH and is responsible for approximately 45% of deaths in the HCC patients. Cirrhosis is almost always present when HCC is diagnosed. Dietary iron overload is a condition which occurs in rural-dwelling Black Africans in southern Africa as a result of the consumption, over time, of large volumes of alcohol home-brewed in iron containers and having, as a consequence, a high iron content. Iron loading of the liver results and may be complicated by malignant transformation of the liver (relative risk of approximately 10.0). Accompanying cirrhosis does occur but is less common than that in HH. The development of HCC as a consequence of increased dietary iron, and the fact that it may develop in the absence of cirrhosis, has been confirmed in an animal model. Drinking water with a high iron content might contribute to the high incidence of HCC in parts of Taiwan. The metabolic syndrome [obesity, insulin resistance type 2 (or diabetes mellitus type 2), non-alcoholic fatty liver or non-alcoholic steatohepatitis] has in recent years become a major public health problem in some resource-rich countries. A link between excess body iron and insulin resistance or the metabolic syndrome has become apparent. The metabolic syndrome may be complicated by the supervention of HCC, and recent evidence suggests that increased body iron may contribute to this complication. PMID:24804175

Kew, Michael C

2014-03-01

380

Hepatic Iron Overload and Hepatocellular Carcinoma  

PubMed Central

In recent years it has become increasingly evident that excess body iron may be complicated by the supervention of hepatocellular carcinoma (HCC). Hereditary hemochromatosis (HH) was the first condition in which hepatic iron overload was shown to predispose to the development of HCC. The inherited predisposition to excessive absorption of dietary iron in HH is almost always the result of homozygosity of the C282Y mutation of the HFE gene, which causes inappropriately low secretion of hepcidin. HCC develops in 8-10% of patients with HH and is responsible for approximately 45% of deaths in the HCC patients. Cirrhosis is almost always present when HCC is diagnosed. Dietary iron overload is a condition which occurs in rural-dwelling Black Africans in southern Africa as a result of the consumption, over time, of large volumes of alcohol home-brewed in iron containers and having, as a consequence, a high iron content. Iron loading of the liver results and may be complicated by malignant transformation of the liver (relative risk of approximately 10.0). Accompanying cirrhosis does occur but is less common than that in HH. The development of HCC as a consequence of increased dietary iron, and the fact that it may develop in the absence of cirrhosis, has been confirmed in an animal model. Drinking water with a high iron content might contribute to the high incidence of HCC in parts of Taiwan. The metabolic syndrome [obesity, insulin resistance type 2 (or diabetes mellitus type 2), non-alcoholic fatty liver or non-alcoholic steatohepatitis] has in recent years become a major public health problem in some resource-rich countries. A link between excess body iron and insulin resistance or the metabolic syndrome has become apparent. The metabolic syndrome may be complicated by the supervention of HCC, and recent evidence suggests that increased body iron may contribute to this complication.

Kew, Michael C.

2014-01-01

381

Ca2+ channel blockers reverse iron overload by a new mechanism via divalent metal transporter-1  

Microsoft Academic Search

Hereditary hemochromatosis and transfusional iron overload are frequent clinical conditions associated with progressive iron accumulation in parenchymal tissues, leading to eventual organ failure. We have discovered a new mechanism to reverse iron overload—pharmacological modulation of the divalent metal transporter-1 (DMT-1). DMT-1 mediates intracellular iron transport during the transferrin cycle and apical iron absorption in the duodenum. Its additional functions in

Susanne Ludwiczek; Igor Theurl; Martina U Muckenthaler; Martin Jakab; Sabine M Mair; Milan Theurl; Judit Kiss; Markus Paulmichl; Markus Ritter; Matthias W Hentze; Guenter Weiss

2007-01-01

382

Recovery of iron from copper slag by deep reduction and magnetic beneficiation  

NASA Astrophysics Data System (ADS)

Aiming at recovering iron from high-iron-content copper slag, this article introduced a combination technology of deep reduction and magnetic beneficiation, investigated the iron recovery efficiency and optimized the technical conditions. When coke powder with 86wt% fixed carbon was used as a reductant, iron was successfully extracted from the copper slag. Under the optimized condition of the coke powder content of 14wt%, the calcium-to-silicon mass ratio (Ca/Si) of 0.2, the roasting temperature of 1300°C, the roasting time of 3 h, the grinding time of 20 min, and the magnetic field intensity of 61 kA·m-1, the iron recovery rate of the copper slag can reach 91.82%, and the extracted iron powder has an iron grade of 96.21%. With the characteristics of high iron grade and low impurity content, the extracted iron powder can be used as high-quality raw materials of weathering steel.

Li, Ke-qing; Ping, Shuo; Wang, Hong-yu; Ni, Wen

2013-11-01

383

Lipid peroxidation, calcium, iron, and TCDD toxicity in rats  

SciTech Connect

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) has been studied as a prototype of halogenated aromatic hydrocarbons. Previous studies have shown that TCDD enhances hepatic lipid peroxidation. This study on TCDD administration to rats was conducted to: measure induction of lipid peroxidation in hepatic and extrahepatic tissues; compare lipid peroxidation between sexes; determine the contributions of H/sub 2/O/sub 2/ and other reactive oxygen species and associated enzymes on hepatic lipid peroxidation: determine the role of iron in TCDD-induced lipid peroxidation; and investigate the relationship between TCDD-induced alterations in lipid peroxidation, calcium homeostasis, reduced glutathione content (GSH) and selenium-dependent glutathione peroxidase activity (GSH-Px). The results demonstrated that TCDD induces changes in microsomal lipid peroxidation in hepatic and extrahepatic tissues. The rates of microsomal lipid peroxidation in male rats were less than in microsomes from female rats. TCDD treatment produced a significant increase in lipid peroxidation which preceded an increase in whole homogenate and mitochondrial calcium content, but paralleled an increase in microsomal calcium content. TCDD treatment produced dose and time dependent decreases in hepatic GSH content and GSH-Px activity in female rats. H/sub 2/O/sub 2/ and possibly hydroxyl radical and singlet oxygen are involved in TCDD-induced hepatic microsomal lipid peroxidation. The results support the hypothesis that the toxicity of TCDD and its lack of tissue selectivity in male and female rats may be due in part to lipid peroxidation. Lipid peroxidation may alter membrane permeability to calcium and lead to sequestration of calcium.

Al-Bayati, Z.A.F.

1986-01-01

384

Thermomagnetic evidence of native iron in sediments  

NASA Astrophysics Data System (ADS)

The paper summarizes the results of thermomagnetic analysis concerning the distribution of metallic iron in the sediments ranging in age from Miocene to Early Cretaceous sampled from the following sections: Gams (Austria); Verkhorech'e and Sel'bukhra (the Crimea); Kvirinaki and Tetritskaro (Georgia); Aimaki, Dzhengutai, Madzhalis, and Gergebil (Ciscaucasia, Russia); Klyuchi and Teplovka (Volga region, Russia); Koshak (Kazakhstan); and Khalats and Kara-Kala (Turkmenia). Small amounts of native iron (from 10-5% to 0.05%) are identified in 521 samples of 921 studied; i.e., iron particles are almost pervasive. This fact traces the origin of these particles to cosmic dust. Some established features point to the heterogeneous character of the cosmic dust: (a) the samples clearly fall into two groups. One group comprises the rocks that contain iron particles; the rocks of the other group are iron-free. In the first group,