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Ferritin
Kinds of Ferritin Terms modified by Ferritin Selected AbstractsVariable-field relaxometry of iron-containing human tissues: a preliminary studyCONTRAST MEDIA & MOLECULAR IMAGING, Issue 4 2009Aline Hocq Abstract Excess iron is found in brain nuclei from neurodegenerative patients (with Parkinson's, Alzheimer's and Huntington's diseases) and also in the liver and spleen of cirrhosis, hemochromatosis and thalassaemia patients. Ferritin, the iron-storing protein of mammals, is known to darken T2 -weighted MR images. Understanding NMR tissue behavior may make it possible to detect those diseases, to follow their evolution and finally to establish a protocol for non-invasive measurement of an organ's iron content using MRI methods. In this preliminary work, the MR relaxation properties of embalmed iron-containing tissues were studied as well as their potential correlation with the iron content of these tissues. Relaxometric measurements (T1 and T2) of embalmed samples of brain nuclei (caudate nucleus, dentate nucleus, globus pallidus, putamen, red nucleus and substantia nigra), liver and spleen from six donors were made at different magnetic fields (0.00023,14 T). The influence of the inter-echo time on transverse relaxation was also studied. Moreover, iron content of tissues was determined by inductively coupled plasma atomic emission spectroscopy. In brain nuclei, 1/T2 increases quadratically with the field and depends on the inter-echo time in CPMG sequences at high fields, both features compatible with an outer sphere relaxation theory. In liver and spleen, 1/T2 increases linearly with the field and depends on the inter-echo time at all fields. In our study, a correlation between 1/T2 and iron concentration is observed. Explaining the relaxation mechanism for these tissues is likely to require a combination of several models. The value of 1/T2 at high field could be used to evaluate iron accumulation in vivo. In the future, confirmation of those features is expected to be achieved from measurements of fresh (not embalmed) human tissues. Copyright © 2009 John Wiley & Sons, Ltd. [source] The role of the inflammatory markers ferritin, transferrin and fibrinogen in the relationship between major depression and cardiovascular disorders , The German Health Interview and Examination SurveyACTA PSYCHIATRICA SCANDINAVICA, Issue 2 2010B. T. Baune Baune BT, Neuhauser H, Ellert U, Berger K. The role of the inflammatory markers ferritin, transferrin and fibrinogen in the relationship between major depression and cardiovascular disorders , The German Health Interview and Examination Survey. Objective:, To determine levels of inflammation (ferritin, transferrin and fibrinogen) in major depression (MDD) and comorbid cardiovascular disease (CVD) in an adult population. Method:, In 4181 participants of the German Health Interview and Examination Survey MDD was assessed through the Composite International Diagnostic Interview (CIDI). Coronary heart disease, stroke, and hypertension were diagnosed by a computer-assisted physician interview. Analyses were performed using anova models stratified for gender. Results:, Ferritin, transferrin and fibrinogen levels showed opposing patterns in individuals with either CVD or MDD alone. In comorbidity analyses, male participants with MDD plus comorbid CHD or hypertension had lower levels of ferritin and lower fibrinogen levels in hypertension compared to men without MDD, while in women, results were inconsistent. Conclusion:, Opposing patterns of inflammatory markers in CVD or MDD alone were reversed when both conditions were present. MDD reduced levels of ferritin, transferrin and fibrinogen in CVD in a gender-specific way. [source] Electrochemically Induced Iron Release of Adsorbed Horse Spleen Ferritin: Quantitation of Iron Using Long Optical Path Length Thin-Layer SpectroelectrochemistryELECTROANALYSIS, Issue 23 2007Abstract In this work, long optical path length thin-layer electrochemical cell was constructed using indium-tin oxide on glass as the electrode material. Iron release from ferritin adsorbed on the electrode was induced by applying a negative potential sweep in the presence of 1,10-phenanthroline. The usefulness of spectroelectrochemistry as a means of determining the quantity of iron released from an adsorbed layer of ferritin is demonstrated. [source] Impact of parturition on iron status in nonanaemic iron deficiencyEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 10 2003A. Krafft Abstract Background, Iron-deficient nonanaemic parturients risk underdiagnosis as a result of the reliance on postpartum ferritin and haemoglobin as markers of iron status. Ferritin is an acute-phase protein whose levels increase during the inflammatory response, as occurs after delivery. Our aims were to evaluate the impact of parturition on iron status, erythropoiesis and the inflammatory response, and identify the optimal parameters and timing for diagnosing iron deficiency in the presence of postpartum inflammation. Materials and methods, Conventional parameters of iron status, erythropoiesis and the inflammatory response (serum ferritin, serum iron, transferrin saturation, C-reactive protein) were compared with more recent parameters [soluble transferrin receptors (sTfR), hypochromic red cells, reticulocyte indices] within 48 h either side of delivery in 64 iron-deficient nonanaemic women (defined by a prepartum serum ferritin , 15 µg L,1, and a pre- and postpartum haemoglobin of , 11·0 g dL,1 and , 10·0 g dL,1, respectively). Results, Mean sTfR decreased pre to postpartum from 7·3 to 5·8 µg mL,1 (P < 0·01), while mean serum ferritin increased from 9·7 to 16·9 µg L,1 (P < 0·01). Serum ferritin did not correlate with haemoglobin pre or postpartum (r = 0·04, P = 0·7; r = 0·2, P = 0·09), but a correlation persisted postpartum between hypochromic red blood cells and haemoglobin (r = ,0·26; P < 0·05). The percentage of hypochromic red cells remained virtually unchanged pre- and postpartum (4·0% vs. 3·8%; NS). Postpartum mean reticulocyte haemoglobin content (CHr) was 27·1 ± 1·6 pg. Conclusion, Iron status should be tested prepartum, in the absence of an inflammatory response, rather than in the early postpartum. A valuable additional parameter, where available, might be the hypochromic red cell percentage, which is virtually uninfluenced by the inflammatory response. Furthermore, hypochromic red cell percentage, CHr and sTfR can be helpful to differentiate between functional iron deficiency and depleted iron stores. [source] Identification of a 250 kDa putative microtubule-associated protein as bovine ferritinFEBS JOURNAL, Issue 3 2005Evidence for a ferritin, microtubule interaction We reported previously on the purification and partial characterization of a putative microtubule-associated protein (MAP) from bovine adrenal cortex with an approximate molecular mass of 250 kDa. The protein was expressed ubiquitously in mammalian tissues, and bound to microtubules in vitro and in vivo, but failed to promote tubulin polymerization into microtubules. In the present study, partial amino acid sequencing revealed that the protein shares an identical primary structure with the widely distributed iron storage protein, ferritin. We also found that the putative MAP and ferritin are indistinguishable from each other by electrophoretic mobility, immunological properties and morphological appearance. Moreover, the putative MAP conserves the iron storage and incorporation properties of ferritin, confirming that the two are structurally and functionally the same protein. This fact led us to investigate the interaction of ferritin with microtubules by direct electron microscopic observations. Ferritin was bound to microtubules either singly or in the form of large intermolecular aggregates. We suggest that the formation of intermolecular aggregates contributes to the intracellular stability of ferritin. The interactions between ferritin and microtubules observed in this study, in conjunction with the previous report that the administration of microtubule depolymerizing drugs increases the serum release of ferritin in rats [Ramm GA, Powell LW & Halliday JW (1996) J Gastroenterol Hepatol11, 1072,1078], support the probable role of microtubules in regulating the intracellular concentration and release of ferritin under different physiological circumstances. [source] Reply: Ferritin and Liver Allocation?HEPATOLOGY, Issue 1 2010Impact on Mortality Not Only on the Waiting List But Also After Orthotopic Liver Transplantation Should Be Considered No abstract is available for this article. [source] Nanocomposite Hydrogel with High Toughness for BioactuatorsADVANCED MATERIALS, Issue 17 2009Min Kyoon Shin Ferritin-based nanofibrous hydrogels that demonstrate synergy between the ferritin protein and the synthetic polymer matrix are fabricated. The hybrid hydrogels showed enhanced mechanical properties and repeated expansion and contraction without showing severe creep during pH switching. The ferritin nanoparticles incorporated into the hydrogel nanofibers improved the actuation stability of a hydrogel actuator by acting as elastic nanosprings in a nanoscale polymer. [source] Intracellular Distribution of Macrophage Targeting Ferritin,Iron Oxide NanocompositeADVANCED MATERIALS, Issue 4 2009Masaki Uchida Intracellular distribution of iron oxide nanoparticles incorporated within a ferritin mutant that displays genetically introduced cell-targeted peptides (RGD-4C) on its exterior surface are investigated using scanning transmission electron microscopy with a high-angle annular dark-field detector. The particles (indicated by arrows) internalized into macrophages much more effectively than those with noncell-targeted ferritin. [source] Ferritin assays on the Beckman Access using EDTA-plasma samplesINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 1p1 2010S. O'Broin No abstract is available for this article. [source] Macrophage aggregates in gilthead sea bream fed copper, iron and zinc enriched dietsJOURNAL OF FISH BIOLOGY, Issue 2 2000M. Manera Gilthead sea bream Sparus aurata from consecutive year classes (0+ and 1+) and from the same parent stock were fed four diets, three of which were fortified with copper, iron and zinc. Concentrations of these elements were little affected by the diet. Hepatic, renal and splenic tissues sections were examined to detect the influence of the diet on the number and morphology of macrophage aggregates (MAs); in particular their structure was examined in the spleen. Three different types of MAs were detected: (1) unstructured, (2) partially structured and scarcely defined and (3) fully structured and well defined. Melanin was the most abundant pigment in the pigmented macrophages which form MAs and the amount of this pigment was influenced by season. Ferritin, in contrast with previous data obtained in other fish species, was more abundant in renal than in splenic MAs. Significant differences in splenic MA numbers among fish fed different diets and among different periods of the year were detected. The results suggest that a polyfactorial regulation could act on the splenic MA number in gilthead sea bream. [source] Effect of inflammatory attacks in the classical type hyper-IgD syndrome on immunoglobulin D, cholesterol and parameters of the acute phase responseJOURNAL OF INTERNAL MEDICINE, Issue 3 2004A. Simon Abstract. Background., Classical type hyper-immunoglobulin D (IgD) syndrome (HIDS) is an hereditary auto-inflammatory disorder, characterized by recurrent episodes of fever, lymphadenopathy, abdominal distress and a high serum concentration of IgD. It is caused by mevalonate kinase deficiency. Objective., To further characterize the acute phase response during fever attacks in HIDS in order to improve diagnosis. Subjects., Twenty-two mevalonate kinase-deficient HIDS patients. Methods., Blood samples were drawn during and in between febrile attacks, and concentrations ofC-reactive protein (CRP), ferritin, procalcitonin, pentraxin 3, IgD and cholesterol in several lipoprotein fractions were determined. Results., The marked acute phase response at the time of a fever attack in classical type HIDS is reflected by a rise in CRP accompanied by a moderate but statistically significant rise in procalcitonin and pentraxin 3. In only two of 22 patients, procalcitonin concentration rose above 2 ng mL,1 during fever attack, compatible with the noninfectious nature of these attacks. Ferritin does not reach the high concentrations found in adult-onset Still's disease. Despite the defect in mevalonate kinase, a component of cholesterol metabolism, serum cholesterol did not change during attacks. IgD concentration is elevated regardless of disease activity, although there is appreciable variation during life. Its role in HIDS remains unclear. Conclusion., The combination of high CRP concentration plus procalcitonin concentration <2 ng mL,1 in a symptomatic HIDS patient might indicate a febrile attack without (bacterial) infection; this observation warrants further investigation for its usefulness as a marker in clinical practice. [source] Divergent modulation of iron regulatory proteins and ferritin biosynthesis by hypoxia/reoxygenation in neurones and glial cellsJOURNAL OF NEUROCHEMISTRY, Issue 5 2005Carlo Irace Abstract Ferritin, the main iron storage protein, exerts a cytoprotective effect against the iron-catalyzed production of reactive oxygen species, but its role in brain injury caused by hypoxia/reoxygenation is unclear. Ferritin expression is regulated mainly at post-transcriptional level by iron regulatory proteins (IRP1 and IRP2) that bind specific RNA sequences (IREs) in the 5,untranslated region of ferritin mRNA. Here, we show that hypoxia decreases IRP1 binding activity in glial cells and enhances it in cortical neurons. These effects were reversed by reoxygenation in both cell types. In glial cells there was an early increase of ferritin synthesis during hypoxia and reoxygenation. Conversely, in cortical neurons, ferritin synthesis increased during the late phase of reoxygenation. Steady-state analysis of ferritin mRNA levels suggested that ferritin synthesis is regulated mainly post-transcriptionally by IRPs in glioma cells, both transcriptionally and post-transcriptionally in type-1 astrocytes, and mainly at transcriptional level in an IRP-independent way in neurons. The different regulation of ferritin expression may account for the different vulnerability of neurons and glial cells to the injury elicited by oxygen and glucose deprivation (OGD)/reoxygenation. The greater vulnerability of cortical neurons to hypoxia-reoxygenation was strongly attenuated by the exogenous administration of ferritin during OGD/reoxygenation, suggesting the possible cytoprotective role exerted by this iron-segregating protein. [source] Ferroportin q248h, Dietary Iron, and Serum Ferritin in Community African-Americans With Low to High Alcohol ConsumptionALCOHOLISM, Issue 11 2008Victor R. Gordeuk Background:, Alcohol consumption is associated with increased iron stores. In sub-Saharan Africa, high dietary ionic iron and the ferroportin Q248H allele have also been implicated in iron accumulation. We examined the associations of ferroportin Q248H, alcohol and dietary iron with serum ferritin, aspartate aminotransaminase (AST) and alanine aminotransaminase (ALT) concentrations in African-Americans. Methods:, Inner-city African-Americans (103 men, 40 women) were recruited from the community according to reported ingestion of >4 alcoholic drinks/d or <2/wk. Typical daily heme iron, nonheme iron and alcohol were estimated using University of Hawaii's multiethnic dietary questionnaire. Based on dietary questionnaire estimates we established categories of < versus ,56 g alcohol/d, equivalent to 4 alcoholic drinks/d assuming 14 g alcohol per drink. Results:, Among 143 participants, 77% drank <56 g alcohol/d and 23%,56 g/d as estimated by the questionnaire. The prevalence of ferroportin Q248H was 23.3% with alcohol >56 g/d versus 7.5% with lower amounts (p = 0.014). Among subjects with no history of HIV disease, serum ferritin concentration had positive relationships with male gender (p = 0.041), alcohol consumption (p = 0.021) and ALT concentration (p = 0.0001) but not with dietary iron intake or ferroportin Q248H. Serum AST and ALT concentrations had significant positive associations with male gender and hepatitis C seropositivity but not with alcohol or dietary iron intake or ferroportin Q248H. Conclusions:, Our findings suggest a higher prevalence of ferroportin Q248H with greater alcohol consumption, and this higher prevalence raises the possibility that the allele might ameliorate the toxicity of alcohol. Our results suggest that alcohol but not dietary iron contributes to higher body iron stores in African-Americans. Studies with larger numbers of participants are needed to further clarify the relationship of ferroportin Q248H with the toxicity of alcohol consumption. [source] Circularly Polarized Luminescent CdS Quantum Dots Prepared in a Protein Nanocage,ANGEWANDTE CHEMIE, Issue 39 2010Dr. Masanobu Naito In Ferritin (einem ,-Helix-reichen, rhombischen, dodekaedrischen Protein) hergestellte CdS-Quantenpunkte (CdS-QDs) zeigen linkshändige circular polarisierte Lumineszenz (CPL) aus einem direkten Übergang und aus Oberflächenstörstellen, die relativ große Anisotropiefaktoren aufweisen. Bei Laser-Photoätzen findet man mit abnehmender QD-Größe eine Blauverschiebung der PL/CPL-Banden von Oberflächenstörstellen, und die Bande des direkten Übergangs verschwindet. [source] Effects of radio frequency magnetic fields on iron release from cage proteinsBIOELECTROMAGNETICS, Issue 5 2009Oscar Céspedes Abstract Ferritin, the iron cage protein, contains a superparamagnetic ferrihydrite nanoparticle formed from the oxidation and absorption of Fe2+ ions. This nanoparticle increases its internal energy when exposed to alternating magnetic fields due to magnetization lag. The energy is then dissipated to the surrounding proteic cage, affecting its functioning. In this article we show that the rates of iron chelation with ferrozine, an optical marker, are reduced by up to a factor of 3 in proteins previously exposed to radio frequency magnetic fields of 1 MHz and 30 µT for several hours. The effect is non-thermal and depends on the frequency-amplitude product of the magnetic field. Bioelectromagnetics 30:336,342, 2009. © 2009 Wiley-Liss, Inc. [source] Hepatic and cardiac iron overload among patients with end-stage liver disease referred for liver transplantationCLINICAL TRANSPLANTATION, Issue 5 2010Avital Y. O'Glasser O'Glasser AY, Scott DL, Corless CL, Zaman A, Sasaki A, Gopal DV, Rayhill SC, Orloff SL, Ham JM, Rabkin JM, Flora K, Davies CH, Broberg CS, Schwartz JM. Hepatic and cardiac iron overload among patients with end-stage liver disease referred for liver transplantation. Clin Transplant 2009 DOI: 10.1111/j.1399-0012.2009.01136.x. © 2009 John Wiley & Sons A/S. Abstract:,Background:, Iron overload is associated with fatal cardiovascular events following liver transplantation. Myocardial iron deposits were observed post-mortem in patients who died of cardiac events after transplantation at our institution. This observation prompted testing to exclude cardiac iron in subsequent transplant candidates. Aims:, To assess the results of testing for iron overload in liver transplant candidates at our institution. Methods:, Ferritin, TIBC, and serum iron were measured in cirrhotics referred for transplantation. Patients with transferrin saturation ,50% and ferritin ,250 ng/mL underwent liver biopsy graded for iron. Patients with 3,4+ hepatic iron deposits underwent HFE mutation analysis and endomyocardial biopsy with iron staining. Results:, Eight hundred and fifty-six patients were evaluated for liver transplantation between January 1997 and March 2005. Two hundred and eighty-seven patients (34%) had transferrin saturation ,50% and ferritin ,250 ng/mL. Patients with markers of iron overload had more advanced liver disease than those with normal iron indices. One hundred and fifty-three patients underwent liver biopsy. Twenty-six patients (17%) had 3,4+ hepatic iron staining. One patient was a C282Y heterozygote. Endomyocardial biopsy was performed in 14 patients of whom nine had cardiac iron deposition. Conclusions:, Non-HFE-related cardiac iron overload can occur in advanced liver disease We therefore recommend screening for cardiac iron prior to liver transplantation. [source] Functional characterization of artemin, a ferritin homolog synthesized in Artemia embryos during encystment and diapauseFEBS JOURNAL, Issue 4 2007Tao Chen Oviparously developing embryos of the crustacean Artemia franciscana encyst and enter diapause, exhibiting a level of stress tolerance seldom seen in metazoans. The extraordinary stress resistance of encysted Artemia embryos is thought to depend in part on the regulated synthesis of artemin, a ferritin superfamily member. The objective of this study was to better understand artemin function, and to this end the protein was synthesized in Escherichia coli and purified to apparent homogeneity. Purified artemin consisted of oligomers approximately 700 kDa in molecular mass that dissociated into monomers and a small number of dimers upon SDS/PAGE. Artemin inhibited heat-induced aggregation of citrate synthase in vitro, an activity characteristic of molecular chaperones and shown here to be shared by apoferritin and ferritin. This is the first report that apoferritin/ferritin may protect cells from stress other than by iron sequestration. Stably transfected mammalian cells synthesizing artemin were more resistant to heat and H2O2 than were cells transfected with vector only, actions also shared by molecular chaperones such as the small heat shock proteins. The data indicate that artemin is a structurally modified ferritin arising either from a common ancestor gene or by duplication of the ferritin gene. Divergence, including acquisition of a C-terminal peptide extension and ferroxidase center modification, eliminated iron sequestration, but chaperone activity was retained. Therefore, because artemin accumulates abundantly during development, it has the potential to protect embryos from stress during encystment and diapause without adversely affecting iron metabolism. [source] Gold nanoparticles induce protein crystallizationCRYSTAL RESEARCH AND TECHNOLOGY, Issue 6 2008F. Hodzhaoglu Abstract Nucleation of protein crystals by gold nanoparticles was observed. Lysozyme and ferritin were used as model proteins. The effect was established with uncoated gold nanoparticles and with gold nanoparticles coated by 16-mercaptodecanoic acid. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Sedimentation as a tool for crystallization from protein mixturesCRYSTAL RESEARCH AND TECHNOLOGY, Issue 11 2006I. Dimitrov Abstract Crystals from apoferritin which is an iron-free form of protein ferritin were obtained from protein mixtures lysozyme/apoferritin using sedimentation under high gravity. Solution containing apoferritin at concentration as high as 5mg/ml in the presence of 25mg/ml lysozyme and overlaid on 5%(w/v) CdSO4 in 0,2M/L NaAC, pH=5 still favors apoferritin crystal formation under normal gravity conditions, but at apoferritin concentrations <0,5mg/ml (,1,14µM/L) in 25mg/ml (,1,71mM/L) lysozyme only the sedimentation in a centrifuge appears to be useful for separating the apoferritin molecules from the mixture followed by apoferritin crystallization in the same system. The very high molecule number ratio (,1:103) of two proteins is used to stress on the observed effect. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Serum Iron and Matrix Metalloproteinase-9 Variations in Limbs Affected by Chronic Venous Disease and Venous Leg UlcersDERMATOLOGIC SURGERY, Issue 6 2005Paolo Zamboni MD Background. Severe chronic venous disease (CVD) is characterized by both dermal hemosiderin accumulation and matrix metalloproteinase (MMP) hyperactivation. The iron-driven pathway is one of the recognized mechanisms of MMP hyperactivation. Objective. To investigate the potential consequences of leg hemosiderin deposits on both iron metabolism and activation of MMPs. Methods. We contemporaneously assessed the following in the serum of the arm and ankle veins of 30 patients (C4,6) with CVD and 14 normal subjects: ferritin, transferrin, iron, percentage of transferrin iron binding capacity (%TIBC), and MMP-9. Optical microscopy examinations with Perls' staining of chronic wounds were also performed. Results. Histology consistently revealed iron deposits. Serum ferritin, iron, and %TIBC were significantly increased in the legs affected by severe CVD compared with the arm of the same subjects or the controls. In addition, iron and %TIBC were significantly elevated in the legs of ulcer patients. The rate of activation of MMP-9 was significantly elevated in CVD. Conclusions. The increased iron deposition in legs affected by CVD seems to be more instable in ulcer patients, leading to iron release in the serum of the affected leg. Our data suggest the iron-driven pathway as a further mechanism for MMP hyperexpression leading to tissue lesion. [source] The role of the inflammatory markers ferritin, transferrin and fibrinogen in the relationship between major depression and cardiovascular disorders , The German Health Interview and Examination SurveyACTA PSYCHIATRICA SCANDINAVICA, Issue 2 2010B. T. Baune Baune BT, Neuhauser H, Ellert U, Berger K. The role of the inflammatory markers ferritin, transferrin and fibrinogen in the relationship between major depression and cardiovascular disorders , The German Health Interview and Examination Survey. Objective:, To determine levels of inflammation (ferritin, transferrin and fibrinogen) in major depression (MDD) and comorbid cardiovascular disease (CVD) in an adult population. Method:, In 4181 participants of the German Health Interview and Examination Survey MDD was assessed through the Composite International Diagnostic Interview (CIDI). Coronary heart disease, stroke, and hypertension were diagnosed by a computer-assisted physician interview. Analyses were performed using anova models stratified for gender. Results:, Ferritin, transferrin and fibrinogen levels showed opposing patterns in individuals with either CVD or MDD alone. In comorbidity analyses, male participants with MDD plus comorbid CHD or hypertension had lower levels of ferritin and lower fibrinogen levels in hypertension compared to men without MDD, while in women, results were inconsistent. Conclusion:, Opposing patterns of inflammatory markers in CVD or MDD alone were reversed when both conditions were present. MDD reduced levels of ferritin, transferrin and fibrinogen in CVD in a gender-specific way. [source] The long-term impact of ferritin level on treatment and complications of type 2 diabetesDIABETES OBESITY & METABOLISM, Issue 6 2008L. Jiang Aim:, To investigate if high-serum ferritin has long-term impact on response to treatment and the development of diabetic complications in patients with type 2 diabetes. Research design and methods:, We analysed the record of 90 consecutive type 2 diabetic subjects who had serum ferritin level determined soon after diagnosis of diabetes and who also had long-term follow-up data. Results:, Patients with higher serum ferritin level had slightly worse triglyceride, blood pressure and liver enzyme levels at the end of follow up. However, ferritin level had no impact on the initial or final requirements for diabetic medication and the development of diabetic complications. Conclusions:, Although elevated serum ferritin is a marker of insulin resistance and chronic inflammation, it is not necessarily a bad prognostic indicator that should affect the clinician's approach to management. [source] Reduced insulin secretion in normoglycaemic patients with ,-thalassaemia majorDIABETIC MEDICINE, Issue 12 2006N. G. Angelopoulos Abstract Aims To assess insulin sensitivity and secretion in the fasting state in regularly transfused patients with ,-thalassaemia major with normal glucose response during an oral glucose tolerance test and to estimate its possible relation to iron overload. Methods We measured fasting glucose, insulin and C-peptide levels in 24 patients with ,-thalassaemia major and 18 control subjects matched for age and body mass index. Insulin sensitivity and insulin release index were calculated according to the homeostasis model assessment (HOMA). Correlations with age, body mass index and serum ferritin were also calculated. Results Fasting glucose levels in patients were increased compared with control subjects (5.5 ± 0.12 vs. 4.7 ± 0.13 mmol/l, mean ± sem, P < 0.001). Pancreatic B-cell insulin secretion in the fasting state (estimated by SCHOMA) was lower in thalassaemic patients (SCHOMA 88.5 ± 11.11 vs. 184.3 ± 23.72 in control subjects, P < 0.001). Patients were then divided into those with impaired (IFG) and normal (NFG) fasting glucose. SCHOMA was higher in the patients with NFG compared with those with IFG patients (110.6 ± 17.63 vs. 66.3 ± 10.88, respectively, P < 0.05) but estimated insulin sensitivity (ISIHOMA) was similar. Plasma values of C-peptide correlated positively with ferritin (r = 0.42, P = 0.04) and SCHOMA (r = 0.45, P = 0.02) and negatively with ISIHOMA (r = ,0.43, P = 0.03). Conclusions These results support the concept that impaired B-cell function, as reflected by a reduction in the insulin secretion index, is present in ,-thalassaemic patients with normoglycaemia before changes in oral glucose tolerance tests are apparent. [source] Electrochemically Induced Iron Release of Adsorbed Horse Spleen Ferritin: Quantitation of Iron Using Long Optical Path Length Thin-Layer SpectroelectrochemistryELECTROANALYSIS, Issue 23 2007Abstract In this work, long optical path length thin-layer electrochemical cell was constructed using indium-tin oxide on glass as the electrode material. Iron release from ferritin adsorbed on the electrode was induced by applying a negative potential sweep in the presence of 1,10-phenanthroline. The usefulness of spectroelectrochemistry as a means of determining the quantity of iron released from an adsorbed layer of ferritin is demonstrated. [source] Iron Status: A Possible Risk Factor for the First Febrile SeizureEPILEPSIA, Issue 7 2002Azhar S. Daoud Summary: ,Purpose: We conducted a controlled study to investigate the relation of iron status and first febrile seizure (FFS). Methods: Measures of iron sufficiency including hemoglobin concentration (HB), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and plasma ferritin (PF) were prospectively measured in 75 children with FFS and compared with 75 controls matched for age and sex with febrile illnesses without convulsions. Results: Mean ferritin level was significantly lower in cases with FFS (29.5 ± 21.3 ,g/L) than in controls (53.3 ± 37.6 ,g/L) with p = 0.0001. The proportion of subjects with a PF level ,30 ,g/L was significantly higher among children with FFS (49 of 75 vs. 24 of 75) than in controls (p = 0.000). Mean levels of HB, MCV, and MCH also were lower among FFS cases, but differences failed to attain statistical significance. A higher proportion of cases with FFS had an HB <110 g/L, MCV <72 fL, and MCH <24 pg than did the controls, but the differences were not statistically significant. There were no statistically significant differences between the cases and the controls in the mean peak temperature on admission, types of underlying illness, or family history of epilepsy and of febrile convulsion. Conclusions: PF level was significantly lower in children with FFS than in the reference group, suggesting a possible role for iron insufficiency in FFS. [source] Impact of parturition on iron status in nonanaemic iron deficiencyEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 10 2003A. Krafft Abstract Background, Iron-deficient nonanaemic parturients risk underdiagnosis as a result of the reliance on postpartum ferritin and haemoglobin as markers of iron status. Ferritin is an acute-phase protein whose levels increase during the inflammatory response, as occurs after delivery. Our aims were to evaluate the impact of parturition on iron status, erythropoiesis and the inflammatory response, and identify the optimal parameters and timing for diagnosing iron deficiency in the presence of postpartum inflammation. Materials and methods, Conventional parameters of iron status, erythropoiesis and the inflammatory response (serum ferritin, serum iron, transferrin saturation, C-reactive protein) were compared with more recent parameters [soluble transferrin receptors (sTfR), hypochromic red cells, reticulocyte indices] within 48 h either side of delivery in 64 iron-deficient nonanaemic women (defined by a prepartum serum ferritin , 15 µg L,1, and a pre- and postpartum haemoglobin of , 11·0 g dL,1 and , 10·0 g dL,1, respectively). Results, Mean sTfR decreased pre to postpartum from 7·3 to 5·8 µg mL,1 (P < 0·01), while mean serum ferritin increased from 9·7 to 16·9 µg L,1 (P < 0·01). Serum ferritin did not correlate with haemoglobin pre or postpartum (r = 0·04, P = 0·7; r = 0·2, P = 0·09), but a correlation persisted postpartum between hypochromic red blood cells and haemoglobin (r = ,0·26; P < 0·05). The percentage of hypochromic red cells remained virtually unchanged pre- and postpartum (4·0% vs. 3·8%; NS). Postpartum mean reticulocyte haemoglobin content (CHr) was 27·1 ± 1·6 pg. Conclusion, Iron status should be tested prepartum, in the absence of an inflammatory response, rather than in the early postpartum. A valuable additional parameter, where available, might be the hypochromic red cell percentage, which is virtually uninfluenced by the inflammatory response. Furthermore, hypochromic red cell percentage, CHr and sTfR can be helpful to differentiate between functional iron deficiency and depleted iron stores. [source] Heart rate variability in beta-thalassemia patientsEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 5 2009Wasarut Rutjanaprom Abstract Background:, Cardiac failure remains the major cause of death in beta-thalassemia major (TM). Reduced heart rate variability (HRV) is associated with a higher risk of arrhythmias after myocardial infarction and heart failure. We evaluated HRV in TM patients and its relationship with hemodynamics and echocardiographic parameters during a 6-month follow-up. Methods:, Thirty-four TM patients (19 ± 10 yr) and 20 healthy subjects (17 ± 6 yr) were evaluated. Hematologic, biochemical, echocardiographic and HRV parameters were determined at entry and at 6-month follow-up. Time and frequency domain HRV parameters were analyzed from 24-h recorded electrocardiograms. All TM patients received blood transfusion and chelation therapy. Results:, Both time and frequency domain HRV parameters were markedly reduced in TM patients, compared to the control. The significantly improved HRV was seen in correlation with higher hemoglobin (Hb) level when compared within TM group at different time point. No correlation was seen between HRV and serum ferritin, reactive oxygen species (ROS) and non-transferrin bound iron (NTBI). Conclusion:, HRV is depressed in TM patients. HRV was significantly correlated with Hb level, suggesting that anemia greatly influences the cardiac autonomic balance. [source] Use of advanced red blood cell and reticulocyte indices improves the accuracy in diagnosing iron deficiency in pregnant women at termEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 6 2007Mari Ervasti Abstract Objectives:, Detection of iron deficiency during pregnancy with hemoglobin (Hb) and serum measurements is insignificant as the measurements may be affected by e.g. hemodilution or accelerated erythropoiesis. This study tests whether cell indices will give a more reliable measure of iron deficiency in pregnant women at term. Methods:, The population was 202 pregnant women. Using the ADVIA 120 hematology system, Hb, mean cell volume (MCV), percentage of hypochromic red blood cells (%HYPOm) and reticulocytes (%HYPOr), and cellular hemoglobin in reticulocytes (CHr) were tested. Additionally, transferrin saturation (TfSat), ferritin, and transferrin receptor (TfR) were analyzed. Receiver operating characteristic (ROC) curves and area under the ROC curves (AUC) were used as statistical methods. Results:, When TfSat (,11%) was used as the reference test for iron deficiency, %HYPOm and CHr had a sensitivity of 58.1% and 80.7%, while the specificities were 82.6% and 71.3%, respectively. Additionally, the AUC values were %HYPOr 0.80, CHr 0.79, ferritin 0.77, %HYPOm 0.75, TfR 0.67, MCV 0.63 and Hb 0.64. The results provided by the cell indices alone (%HYPOm or CHr) were in good agreement with the results based on the usage of a combination of three commonly used tests (Hb, MCV, ferritin). Conclusions:, This study suggests that the most practical way to diagnose iron deficiency in pregnant women at term is to use cell indices such as CHr and %HYPOm provided by the automated hematological analyzer. Further studies are needed to determine the usefulness of the cell indices in diagnosing iron deficiency longitudinally during the course of pregnancy. [source] Serum transferrin receptor, ferritin, and reticulocyte maturity indices during the first year of life in ,large' preterm infantsEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 5 2007Vassiliki Schiza Abstract Background:, Preterm infants are at risk of developing iron deficiency; among the iron status and hemopoiesis indices the serum transferrin receptor (sTfr) has been shown to be a useful indicator in assessing iron status, while immature reticulocyte production is regarded as an estimator of erythropoiesis. Objective:, To investigate age-related changes in iron status infants born ,moderately' preterm, with a gestational age (GA) of 32,36 wk, and identify associations between sTfr and other hematological and biochemical iron indices. Design:, Hospital-based prospective, longitudinal study in preterm infants. Methods:, Iron and erythropoiesis parameters were evaluated in 181 formula-fed preterm infants at 2 and 6 wk and 3, 6, 9, and 12 months chronological age. Hemoglobulin (Hb), hematocrit (Hct), mean corpuscular volume (MCV), reticulocytes, serum iron (sFe), serum ferritin (sFer), sTfr, and reticulocyte subpopulations were measured. Results:, A total of 756 measurements were performed. After an initial decline, Hb rose from month 3 to 12 of life. SFe and sFer and immature reticulocyte count decreased from the second week to the third month and remained stable thereafter. STfr was lower up to 6 wk and stable from month 3 to 12. Iron deficiency anemia (IDA) was found in 5.5% of infants. In 76 measurements sFer was <12 ,g/L, implying storage iron deficiency (SID). A negative correlation was observed between sTfr and other indices of iron status such as Hb, Hct, MCV, sFe, and sFer. Infants with sFer <12 ,g/L had lower sTfr than those with sFer >12 ,g/L. Reticulocyte production was positively associated with STfr, but this association was dependent on the chronological age of the infant. Conclusion:, Iron depletion is common in formula-fed preterm (32,36 wk GA) infants between month 3 and 12 of life. STfr appears to be an indicator of iron status in preterm infants during the first year of life. [source] Soluble hemoglobin,haptoglobin scavenger receptor CD163 as a lineage-specific marker in the reactive hemophagocytic syndromeEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 1 2005Dominik J. Schaer Abstract:, Reactive hemophagocytic syndrome (RHS) is a disease of overwhelming macrophage activity triggered by infection, malignancy or autoimmune disorders. Currently used laboratory markers for the quantitative assessment of monocyte/macrophage activation lack lineage-restricted expression patterns and thus specificity. Serum levels of the macrophage specific scavenger receptor CD163 were detemined by enzyme-linked immunosorbent assay (ELISA) and were found to be highly increased in patients with RHS (median 39.0 mg/L). Significantly lower levels were determined in patients with sepsis (median 9.1 mg/L), acute mononucleosis (median 8.2 mg/L), Leishmania infection (median 6.7 mg/L) and healthy controls (median 1.8 mg/L). Follow-up of patients with a relapsing course of the disease revealed close correlations of sCD163 with clinical disease activity, serum ferritin and other markers of macrophage activity. Large sinusoidal accumulations of CD163 expressing macrophages actively engaged in phagocytosis of blood cells were detected in spleen sections of RHS patients. Our data suggests sCD163 to be a macrophage-specific marker in patients with disorders of inappropriate macrophage activation. [source] | |||||||||||||||||||||||||||||||||||||||||||