<p>In our first study, we explored the barriers to complying with iron supplement recommendations using focus groups. We recruited adults, ages 18-75 years, who have had bariatric surgery at least two months previously to participate in one of four 90-minute focus groups. Participants filled out a survey asking for information on demographics and supplement use, and a facilitator asked a set of pre-determined questions to each group. Responses were written, recorded, transcribed using TranscribeMe (San Francisco CA), and analyzed using NVivo (QSR International Pty Ltd, Doncaster, Victoria). The focus groups contained nineteen participants, five of which had sleeve gastrectomy (SG) and fourteen had Roux-en-Y gastric bypass (RYGB). The average age of the participants was 49.3 ± 9.4 years, and they had undergone surgery 3.9 ± 3.6 years previously. The key factors that influenced participants’ adherence to supplement guidelines were cost, tolerability, and palatability of the supplement, level of knowledge and support from healthcare providers, and convenience of the supplementation regime.</p> <p>The second study was a prospective observational study to determine the bioavailability of ASP compared to FS. Iron deficient RYGB patients ages 18-65 years, who had surgery at least 6 months previously, participated in 8-hour iron absorption tests. Participants received a low-iron breakfast with 65 mg ASP (N=7) or FS (N=3). We assessed serum iron every 30 minutes for 8 hours following the supplementation using a colorimetric assay (South Bend Medical Foundation, South Bend, IN). In participants administered FS, serum iron increased 96.0 ± 27.2 µg/dL compared to baseline, whereas with ASP, serum iron increased 5.8 ± 4.7 µg/dL compared to baseline (<i>P</i> = 0.02). These data indicate that ASP is not as bioavailable as FS in RYGB patients.</p>

In dieser Studie wurde eine Charakterisierung von Eisenpräparaten entwickelt, die als parenterale und orale Präparate zur Behandlung schwerer Anämie auf Basis von Fe-Kohlenhydrat-Nanopartikeln und Bioverfügbarkeitsstudien in biologischen Proben verwendet werden. Eine vollständige Charakterisierung eines kommerziellen Präparats für die parenterale Behandlung von Anämie (Venofer®) wurde durchgeführt. Solubilisationsstudien des Arzneimittels wurden in Serum und Blut durchgeführt, um die Bioverfügbarkeit von Eisen zu untersuchen. Es wurden Speziationsexperimente von Serumproteinen durchgeführt (UV-vis, ICP-MS), die detailliertere Informationen über das Arzneimittel und sein Verhalten im Körper liefern. Tartrat-modifizierte Eisenoxid-Nanopartikel (FeNPs) und isotopisch angereicherte 57Fe wurden synthetisiert. Nanopartikel wurden weiter in Bezug auf Partikelgröße und -form charakterisiert. Da diese Nanopartikel möglicherweise für die orale Supplementierung bei der Die Labilität dieser FeNPs wurde in saurem Medium bewertet, und das gesamte Fe wurde in nanopartikulärer und löslicher Fraktion quantifiziert. Zur Bestimmung des Nanostrukturverhaltens in zellulären Medien wurde eine Speziationsstrategie für Nanopartikel und ionische Eisenspezies basierend auf einer reversed phase high performance liquid chromatography, gekoppelt an ICP-MS, durchgeführt und erstmals auf Caco-2-Zellen angewendet Proben. Darüber hinaus wurde ein Quantifizierungsansatz durch Anwendung einer Isotopenverdünnungsanalyse mit 57Fe. Die Zytotoxizität wurde untersucht: kolorimetrische Assays wurden in verschiedenen Zelllinien durchgeführt, und die oxidative Schädigung wurde durch Messung der ROS-Produktion bestimmt. Schließlich wurden In-vivo-Modelle zur Bestimmung der Eisenresorption im Dünndarm nach Perfusionsexperimenten an Ratten verwendet. Das Schicksal der FeNPs wurde auch untersucht, indem andere Gewebe wie Leber, Niere, Milz oder Blut nach der intestinalen Aufnahme analysiert wurden. / In this study, a characterization of iron supplements used as parenteral and oral preparations for the treatment of severe anaemia based on Fe-carbohydrate nanoparticles and bioavailability studies in biological samples have been developed. A complete characterization of a commercial preparation for the parenteral treatment of anaemia (Venofer®), has been carried out. Solubilisation studies of the drug have been conducted in serum and blood to evaluate iron bioavailability. Moreover, speciation experiments of serum proteins were conducted using UV-vis and ICP-MS detection, providing more in-depth information about the drug and its behaviour in the body. Tartrate-modified coated-iron oxide nanoparticles (FeNPs) and isotopically enriched 57FeNPs have been synthesized. Nanoparticles were further characterized in terms of particle size and shape. As these nanoparticles are potentially suitable for the oral supplementation in anaemia’s treatment, the lability of these FeNPs in acidic medium was evaluated, and total Fe was quantified in nanoparticulate and soluble fraction. For the determination of nanostructure behaviour in cellular media, a speciation strategy for nanoparticles and ionic species of iron based on a reversed-phase high-performance liquid chromatography coupled to ICP-MS was carried out and applied for the first time to Caco-2 cell samples. Moreover, a quantification approach was also tackled by applying an online post-column isotope dilution analysis with 57Fe as isotopically enriched standard. Cytotoxicity from these tartrate-modified iron oxide nanoparticles was evaluated: colorimetric assays have been conducted in different cell lines and oxidative damage was assessed by measuring ROS production. Finally, in vivo models were used to determine iron absorption in the small intestine after perfusion experiments in rats. The fate of the FeNPs was also studied by analysing other tissues as liver, kidney, spleen, or blood after the intestinal uptake.

Tillgängligheten av blod kan vara livsavgörande för många personer, därför är blodgivning en viktig del av vården. För blodgivare kan en regelbunden blodgivning påverka kroppens järndepåer vilket på sikt kan leda till en järnbrist. Syftet med denna studie var att kartlägga blodgivares järndepåer i Region Jönköpings län genom att (i) utvärdera antalet och andelen nyanmälningar som ej uppfyllt godkänd S-ferritinnivå för blodgivning, (ii) jämföra nivåerna av S-ferritin vid nyregistrering och vid upprepad blodgivning, (iii) utvärdera intag av järnprofylax hos blodgivare, (iv) jämföra antalet, andelen samt orsaken till kontrollprovtagningar före och efter S-ferritin infördes som provtagningsrutin. Data insamlades och erhölls från Blodcentralen, Jönköping, Sverige, och analyserades statistiskt. Resultatet visade att fler kvinnor än män ej blev godkända som blodgivare på grund av S-ferritin &lt;22 µg/L. Genom att sänka S-ferritinnivån kan fler kvinnor godkännas för blodgivning. Vidare visade studien att upprepad blodgivning leder till minskade järndepåer. Grupperna som erbjudits järnprofylax hade stabilare S-ferritin över tid vilket antyder att alla blodgivare skulle gynnas av järnprofylax, men vidare studier krävs. Majoriteten av blodgivare med S-ferritin ≤100 µg/L intar erbjudna järntabletter vilket visade att blodgivarna möjliggjorde fortsatt blodgivning. Slutligen visade studien att sedan S-ferritin infördes som provtagningsrutin 2017 har kontrollprovtagningar på grund av lågt B-Hb minskat, vilket visar att risken för att utveckla en järnbrist på grund av upprepad blodgivning har minskat i Region Jönköpings län. / The availability of blood could be crucial for many people; blood donation is, therefore, a vital part of healthcare. Continuous blood donation could affect the blood donors’ iron depots which could lead to an iron deficiency. The aim of the present study was to evaluate and highlight iron depots amongst blood donors in Jönköping County by (i) evaluating the number and proportion of new applicants which did not meet the approved S-ferritin levels for blood donation, (ii) compare the levels of S-ferritin in new registrations and repeated blood donations, (iii) evaluate intake of iron supplements amongst blood donors, (iv) compare the number, proportion and cause for control sampling before and after S-ferritin was introduced as a sampling routine. Data was collected from the Department of Transfusion Medicine, Jönköping, Sweden, and analysed statistically.The result showed that more women than men were not approved for blood donation because of S-ferritin &lt;22 µg/L. By lowering S-ferritin, additional women will be approved for blood donation. Further, the study showed that continuous blood donation leads to decreased iron depots. Groups that were offered iron supplements showed more stable S-ferritin levels over time which implied that all blood donors would benefit from iron supplements, but further studies are required. The majority of the blood donors with S-ferritin ≤100 µg/L were taking their offered iron supplements which showed that the blood donors enabled future blood donations. Lastly, since S-ferritin was introduced as a sampling routine in 2017 the amount of control samplings due to low B-Hb has decreased. This shows that the risk to develop an iron deficiency due to continuous blood donation has decreased in Jönköping County.

Iron deficiency chlorosis (IDC) is a frequent problem throughout many areas of the United States where soils are high in calcium carbonate (CaCO3), including the Blackland Prairie regions of Mississippi. The main objectives of this study were to 1) determine the effects of seven different cropping systems on IDC visual symptomology and grain yield in rainfed soybeans grown in calcareous soils, and 2) evaluate the effects of soil water tension (SWT) on IDC. Rotating soybeans with corn produced significantly higher yields for both tolerant and susceptible soybean varieties. IDC symptomology was worse, and yields were lower in cropping systems with lower average SWT, or wetter soils, throughout the growing season. Last, this study evaluated the use of multispectral imagery and apparent soil electrical conductivity (ECa) to identify IDC-prone areas of a field for the site-specific implementation of management strategies that produced higher yields in the plot-scale study.

Thesis (M. Tech. (Biomedical Technology)) -- Central University of Technology, Free State, [2014] / Pica is the habitual eating of non-food substances by humans and animals. It has different subgroups and these are defined by the ingested substance. Moreover, geophagia is a type of pica that refers to the consistent eating of mostly earth and earth-like substances such as clay and soil. It is observed in both sexes, all age groups and in different ethnic groups around the world. There are many reasons people give for the practice of geophagia, such as culture, hunger and health being the most prominent. Geophagic materials differ in texture, colour and taste. Soil colour classification according to the Munsell soil classification, which uses hues, values and chroma, sometimes differ with the soil colour being noticeable with the naked eye. However, geophagic clays from Qwa-Qwa are white and contain kaoline. Geophagic materials are believed to augment mineral deficiency, especially magnesium, calcium and iron. Geophagia is practised mainly by females, especially during their child bearing years. Females are more prone to iron deficiency anaemia due to their monthly menstruation cycle. Iron deficiency is the most common cause of anaemia and is classified as hypochromic microcytic anaemia (HMA). This study focused on the health aspect of geophagia. The research question seeks to explore whether there is an association between geophagia and the haematological parameters of iron deficiency anaemia. Geophagia seems to be linked with the occurrence of anaemia, but not iron deficiency anaemia, although it is implied. It is not known if the practice of geophagia causes iron deficiency anaemia or if it is because of iron deficiency anaemia that people practise geophagia. A pilot study was done in 2007, and the results of that study prompted that this study be performed on a bigger scale. The lack of information regarding the quantity, frequency and type of geophagic material consumed the impact of geophagia on haematological parameters and the iron status of the geophagists made it important that the primary existence of the iii relationship be investigated. In addition, research to establish whether there is a relationship between geophagia and haematological parameters of iron deficiency anaemia, has not been undertaken in South Africa, especially on non-pregnant women. Geophagia seems to always be accompanied by the subject of iron deficiency anaemia and especially its prevalence in females. The bigger geophagia project was therefore an ideal opportunity to do a specific survey on geophagic women. This was a cross-sectional study, consisting of 36 control women and 47 geophagic women, aged between 18-45 years. The participants completed a questionnaire to determine the geophagic practices, which included the colour of the clay, how frequent the clay was consumed, how much was consumed and for how long it has been consumed. Nutritional status was assessed using a food frequency questionnaire. Blood was drawn to assess the haematological and iron status of the participants. The participants of the study were within the required age range, with no significant difference between the groups (p-value=0.7914). The most consumed colour of clay was white and white clay contains kaoline, which has the ability to absorb iron in the duodenum. The majority of the participants consumed 40 grams of clay on a daily basis, with most of the participants having done so for 5 years. Diet was ruled out as the cause of iron deficiency. The haematological parameters indicated that the geophagic group (43%) were inclined to have hypochromic microcytic anaemia, while a small percentage of control groups (8%) had HMA; this was revealed by the red cell parameters and red cell indices. In addition, the odds ratio for the haematological results revealed that the probability of a geophagic person developing anaemia was two times greater than that of a non-geophagic person. Platelet results partially ruled out bleeding as a cause of anaemia. The median red cell distribution width indicated that the iv geophagic group was inclined to have anisocytosis. The geophagic group was found to have iron deficiency (75%), whilst the control group had a small percentage with iron deficiency (22%), which was validated by the serum ferritin, serum iron and saturated transferrin (chemical analysis). The odds ratio revealed that the probability of a geophagic person being iron deficient is 3 times greater than that of a non-geophagic person. The strongest association is seen with iron study findings, because being iron deficient showed the highest odd ratio than the association with red cell morphology and even haemoglobin. Thus, participants were more iron deficient than suffering from iron deficiency anaemia. Inflammatory and parasitic indicators proved that inflammation and infection was uncommon in both groups, and therefore did not compromise the credibility of the iron study results. Inflammatory indicators (white blood cells, erythrocyte sedimentation rate and C-reactive protein) ruled out inflammation, whilst eosinophil count showed no indication of parasitic infection for both geophagic and control groups. To conclude, the study found that an association exists between geophagia and haematological parameters of iron deficiency anaemia amongst geophagic women in Qwa-Qwa, in that geophagic material contributes to iron deficiency anaemia.

Thesis (MMed)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: There is growing interest in how genetic and environmental risk factors interact to confer risk for dysregulated iron homeostasis, which is considered a possible pathogenic mechanism in multiple sclerosis (MS). While iron deficiency has been associated with greater disability and disease progression, cerebral accumulation and overload of insoluble iron has also been reported in MS patients. Variation in the matriptase-2 (TMPRSS6) gene has recently been described that may lead to reduced iron levels, which raised the question of whether it may be involved in dysfunctional iron regulation as a pathogenic mechanism in MS. The aims of the study were as follows: 1)) comparison of the allele frequencies and genotype distribution for TMPRSS6 A736V (rs855791, c.2207C>T) and HFE C282Y (rs1800562, c.845G>A) between patients diagnosed with MS and unaffected controls; 2) determination of the effects of clinical characteristics, relevant lifestyle factors and genotype on serum iron parameters in MS patients compared to population matched controls; and 3) determination of clinical outcome in relation to age of onset and degree of disability in MS patients. The study population included 121 Caucasian MS patients and 286 population-matched controls. Serum iron, transferrin, ferritin and transferrin saturation levels were available from previous studies and lifestyle factors were subsequently documented in a subgroup of 68 MS patients and 143 controls using the study questionnaire. Genotyping of TMPRSS6 A736V and HFE C282Y were performed using allele-specific TaqMan technology. The genotype distribution and allele frequencies of TMPRSS6 A736V and HFE C282Y did not differ between MS patients and controls. MS patients homozygous for the iron-lowering minor T-allele of TMPRSS6 A736V had significantly lower serum iron levels (p=0.03) and transferrin saturation levels (p=0.03) compared to CC homozygotes. In MS patients the iron-loading minor A-allele of HFE C282Y was also associated with a paradoxical decrease in serum ferritin (p<0.01) compared to GG homozygotes. When considering the combined effect of the minor alleles of TMPRSS6 A736V and HFE C282Y with opposite effects on iron levels, we found a significant reduction in serum ferritin levels (p<0.05), independent of age, sex, body mass index (BMI) or dietary red meat intake in MS patients. A similar effect was not observed in the population- and age-matched controls. Higher dietary red meat intake correlated significantly with increased ferritin only in controls (p=0.01 vs. 0.21 for MS patients). In the presence of the minor allele of HFE C282Y, the TMPRSS6 A736V CT and TT genotypes were associated with a significantly earlier age of onset of MS when the post hoc test was applied (p=0.04). All the study aims were successfully accomplished. Our results support the possibility of an epistatic effect between TMPRSS6 A736V and HFE C282Y associated with reduced ferritin levels in MS patients. Pathology-supported genetic testing (PSGT) applied in this study as a new concept for analysis of complex diseases with a genetic component, is well placed to optimise clinical management in patients with MS. / AFRIKAANSE OPSOMMING: Daar heers toenemende belangstelling in hoe die wisselwerking tussen genetiese en omgewingsfaktore die risiko tot wanregulering van yster-homeostase beïnvloed. Laasgenoemde is ‘n moontlike patogeniese meganisme vir meervoudige sklerose (MS). Alhoewel verhoogde gestremdheid en siekteprogressie met ystertekort geassosieer is, is ysterophoping in die serebrum asook ‘n oormaat onoplosbare yster al by MS-pasiënte gevind. Variasie in die matriptase-2 (TMPRSS6) geen wat tot verlaging in ystervlakke kan lei, is onlangs beskryf en laat die vraag ontstaan of dit betrokke is by wanregulering van yster-homeostase as patogeniese meganisme in MS. Die doelwitte van die studie was as volg: 1) vergelyking van alleelfrekwensies en genotipeverspreiding vir TMPRSS6 A736V (rs855791, c.2207C>T) en HFE C282Y (rs1800562, c.845G>A) tussen MS-pasiënte en ongeaffekteerde kontroles; 3) bepaling van die effekte van kliniese indikators, relevante leefstylfaktore en genotipe op serum yster parameters in MS-pasiënte in vergelyking met populasie-ooreenstemmende kontroles; en 4) bepaling van kliniese uitkoms ten opsigte van aanvangsouderdom en graad van MS-aantasting. Die studiepopulasie het uit 121 kaukasiese MS-pasiënte en 286 kontroles van dieselfde populasie, wat nie die siekte het nie, bestaan. Serum yster, transferrin, ferritien en transferrien-versadigingsvlakke was beskikbaar vanaf vorige studies. Leefstylfaktore is in ‘n subgroep van 68 MS-pasiënte en 143 kontroles gedokumenteer met behulp van die studie-vraelys. TMPRSS6 A736V en HFE C282Y genotipering is met alleel-spesifieke TaqMan-tegnologie uitgevoer. Beide pasiënte en kontroles het dieselfde genotipeverspreiding en alleelfrekwensies getoon. Die A-alleel van HFE C282Y is met ‘n paradoksale verlaging in serum ferritien geassosieer (p<0.01) in MS-pasiënte met TMPRSS6 A736V, moontlik weens geen-geen interaksie wat nie deur ouderdom, liggaamsmassa-indeks of inname van rooivleis in die dieet beïnvloed is nie (p<0.05) en nie by kontroles gevind is nie. MS-pasiënte wat homosigoties is vir die T-alleel van TMPRSS6 A736V, het statisties betekenisvolle laer serum ystervlakke (p=0.03) en transferrienversadiging (p=0.03) getoon in vergelyking met CC-homosigote. In MS-pasiënte was die yster-oorlading A-alleel van HFE C282Y ook geassosieer met ‘n paradoksale afname in serum ferritien (p<0.01) in vergelyking met GG-homosigote. Wanneer die gekombineerde effek van die risiko-geassosieerde allele van TMPRSS6 A736V en HFE C282Y met teenoorgestelde effekte op ystervlakke geanaliseer word, is daar ‘n statisties beteknisvolle afname in serum ferritienvlakke (p<0.05), onafhanklik van ouderdom, geslag, liggaamsmassa-indeks of rooivleisinname in MS-pasiënte. ‘n Soortgelyke effek is nie waargeneem in populasie- en geslag-gelyke kontroles nie. Die inname van rooivleis in die dieet was betekenisvol minder by MS-pasiënte teenoor kontroles (p=0.03) en dit het slegs betekenisvol met verhoogde ferritien by kontroles gekorreleer (p=0.01 teenoor 0.21 by MS-pasiënte). In die teenwoordigheid van die risiko-geassosieerde alleel van HFE C282Y, is die TMPRSS6 A736V CT en TT genotipes geassosieer met ‘n statisties-betekenisvolle vroeër aanvangsouderdom van MS soos bepaal met die post hoc-toets (p=0.04). Al die doelwitte van die studie is suksesvol uitgevoer. Die resultate ondersteun die moontlikheid van ‘n epistatiese effek tussen TMPRSS6 A736V en HFE C282Y wat geassosieer is met ‘n verlaging in ferritienvlakke in MS-pasiënte. Patologie-gesteunde genetiese toetsing soos toegepas in hierdie studie as ‘n nuwe konsep vir analise van komplekse siektes met ‘n genetiese komponent, is goed geplaas om kliniese hantering van MS-pasiënte te optimaliseer.

Ces dernières années, les besoins en électronique de puissance s’orientent vers la miniaturisation globale des cartes électroniques, parallèlement à une augmentation des puissances de travail. C’est dans ce contexte que s’inscrivent les travaux de cette thèse, principalement axée sur l’élaboration, l’amélioration des performances et l’intégration de composants passifs (inductances, transformateurs…) en électronique de puissance.Les matériaux choisis pour remplir les fonctions magnétiques de ces composants dans leurs conditions de travail sont les ferrites NixZn1-xFe2O4 (0<x<1). Du cuivre est ajouté pour diminuer la température de frittage, de plus de 1200 °C à moins de 950°C, permettant le cofrittage avec un métal conducteur, et du cobalt pour diminuer les pertes totales en puissance du ferrite formé. La formulation finale devient alors (NixZnyCuz)1-εCoεFe2-δO4 (x+y+z=1). Enfin, de l’oxyde de bismuth Bi2O3 est ajouté comme fondant pour abaisser encore la température de frittage et éviter les problèmes de diffusion.Après une étude bibliographique, les travaux se sont orientés selon différents axes. Il s’agissait tout d’abord d’optimiser la formulation du ferrite pour élaborer des échantillons aux propriétés électromagnétiques et physicochimiques ciblées. Cet axe de travail regroupe de nombreuses études sur la formulation des ferrites Ni-Zn-Cu-Co, parmi lesquelles les principales sont l’étude de l’influence de la stœchiométrie en fer, du rapport Ni/Zn dans la formulation et du procédé d’ajout de cobalt selon son taux. Ces travaux ont permis de mettre en évidence qu’un léger défaut de fer maîtrisé (~Fe1,98) pouvait améliorer les propriétés et les performances de ces ferrites. L’étude de l’influence du rapport Ni/Zn a permis la réalisation de ferrites à perméabilités très faibles, de 40 à 135, et aux bonnes performances en puissance. Les résultats de cette étude ont été publiés dans le Journal of the Japan Society of Powder and Metallurgy. Tout au long de la thèse, l’élaboration d’échantillons céramiques, base incontournable de chaque étude, a été réalisé au laboratoire, comme la plupart des tests et caractérisations. Ces derniers peuvent être microstructuraux et physicochimiques (DRX, MEB, BET, ATD/ATG…), ou électromagnétiques (mesures d’aimantation, de perméabilité, de pertes en puissances, etc…).La finalité de ces travaux étant l’intégration de puissance, cette dernière représente le second axe majeur, et regroupe également de nombreuses études, parmi lesquelles les principales sont les études des influences du bobinage sur les pertes d’un composant de type inductance et de l’entrefer (espacement amagnétique au sein du circuit magnétique), classiquement utilisé pour diminuer la perméabilité apparente, non sans conséquence sur les performances en puissance. Une campagne de mesures de pertes totales a également été réalisée dans l’objectif de dégager des lois comportementales sur la variation de ces pertes en puissance et en fréquence.Tous ces travaux et leurs résultats sur le matériau ferrite, son utilisation en électronique de puissance, et une bonne maîtrise du procédé d’élaboration (notamment multicouche), ont permis la réalisation de microcomposants passifs intégrables, aux propriétés ciblées et aux très bonnes performances (pertes diminuées d’un facteur 6 à 10 par rapport au commerce). / In recent years, power electronics needs are moving towards the global miniaturization of electronic boards, and an increase of the working powers. The works performed during this thesis, mostly oriented on the elaboration, the performances improvement and the integration of passive components (inductors, transformers…) in power electronics, are inscribed in this context.The materials chosen to perform the magnetic functions of those components in their work conditions are the NixZn1-xFe2O4 (0<x<1) ferrites. Copper is added to reduce the firing temperature, from more than 1200 °C to less than 950 °C, allowing cofiring with a conducting metal, and cobalt is added to reduce the power core losses of the sintered ferrite. The final formulation then becomes (NixZnyCuz)1-εCoεFe2-δO4 (x+y+z=1). Finally, bismuth oxide Bi2O3 is added as a sintering aid to lower even more the sintering temperature and avoid diffusion problems.After a bibliographic study, the works were oriented along different axes. Firstly, the ferrite formulation was optimized to elaborate samples with targeted electromagnetic and physicochemical properties. This working axis gathers numerous studies on the Ni-Zn-Cu-Co ferrites formulation, among which the main ones are the study of the influence of iron stoichiometry, the Ni-Zn ratio in the formulation and the cobalt adding process and level. These studies have shown that a light and controlled iron deficiency (~Fe1,98) could improve the properties and the performances of these ferrites. The study of the influence of the Ni/Zn ratio allowed the production of very low permeability ferrites, from 40 to 135, with good power performances. Its results were published in the Journal of the Japan Society of Powder and Metallurgy. Throughout this thesis, the elaboration of ceramic samples, the essential basis of every study, was undertaken at the laboratory, as most of the tests and characterizations. These can be microstructural and physicochemical (XRD, SEM, BET, TDA/TGA…), or electromagnetic (magnetization and permeability measurements, power losses…).The final purpose of this work is power integration, and it represents the second main axis. It also gathers many studies, among which the main ones are the study of the influence of the winding on the losses of an inductor-type component and the influence of the air gap, commonly used to reduce the apparent permeability, not without consequences on the power performances. A total losses measurement campaign has also been undertaken in order to bring out behavioral laws on core losses variation according to induction and frequency.All this work and the results on the ferrite material, his power electronic application, and a good control of the elaboration process (multilayer especially), allowed the production of passive micro-components for integration, with targeted properties and very high performances (core losses reduced by 6 to 10 relative to commercial materials).

Introdução: Anemia por carência alimentar de ferro é a deficiência nutricional mais freqüente e preocupante do ponto de vista da saúde coletiva. Afeta principalmente crianças, gestantes e mulheres em idade fértil. Apesar das medidas de intervenção para prevenção e controle da anemia no Brasil, estudos mostram que as prevalências ainda continuam elevadas. Objetivo: Investigar a situação da anemia e seus determinantes em mães e filhos no Brasil, considerando o contexto familiar. Método: Pesquisa transversal de abordagem quantitativa, que utilizou o banco de dados da Pesquisa Nacional de Demografia e Saúde da Mulher e da Criança (PNDS) 2006. Foram utilizados dois questionários com informações básicas sobre o domicílio e seus moradores e informações detalhadas sobre o público-alvo, mulheres de 15 a 49 anos e seus filhos menores de 5 anos. Aproximadamente 40% dos domicílios foram selecionados para coleta de sangue das mulheres, porém todas as crianças nascidas a partir de janeiro de 2001 tiveram o sangue colhido, desde que filhos biológicos da entrevistada. Análise de hemoglobina foi realizada em 5.915 mulheres e 4.558 crianças. Este estudo analisou 1.476 pares, considerando a mãe e apenas uma criança. O programa Statistical Package for Social Science (SPSS versão 18.0) foi utilizado para análise dos dados, que analisou anemia em mães e/ou filhos, mães e filhos isoladamente e constou das etapas univariada e múltipla. Resultados: A ocorrência de anemia foi de 36,8% em mães e/ou filhos, 23,4% nas mães e 17,0% nos filhos. Mães apresentaram chance 1,49 vezes maior de ter anemia do que os filhos, e não se verificou associação entre anemia nas mães e nos filhos (p=0,478). Na análise múltipla, mães e/ou filhos que residiam nas regiões Nordeste e Centro-Oeste apresentaram chance 2,24 e 1,70 vezes maior, respectivamente, em relação às da região Sul; a chance também foi estatisticamente maior (1,78 vezes) para o par com insegurança alimentar (sentiu fome) e em que a mãe realizou consulta de puerpério (1,39 vezes); primiparidade mostrou-se como fator de proteção. Anemia nas mães também se associou com macrorregião de residência, com chance 2,39 vezes maior para as da região Nordeste em relação às da região Sul; mães com insegurança alimentar, que realizaram consulta de puerpério e tiveram pelo menos uma doença também apresentaram chance 50% maior para anemia. Nas crianças, anemia associou-se com insegurança e consumo alimentar, sendo que aquelas que ingeriram multimistura e leite fresco com água nas últimas 24 horas apresentaram chance 2,49 e 1,69 vezes maior para anemia, respectivamente, assim como crianças que não ingeriram lanche da tarde no dia anterior e que ingeriram arroz menos de 4 vezes na semana (chance 1,57 e 2,38 vezes maior, respectivamente); primiparidade materna revelou-se como fator de proteção. Conclusões: A ocorrência de anemia em mães e/ou filhos é maior nas macrorregiões menos desenvolvidas e em famílias com insegurança alimentar, o que evidencia a determinação social dessa carência nutricional. É mais freqüente nas mães e não se associa à ocorrência de anemia nos filhos. Nas mães, anemia associa-se com variáveis socioeconômicas, demográficas e insegurança alimentar. Nas crianças, anemia se associa apenas com insegurança e consumo alimentar. Os resultados indicam que embora mães e filhos estejam expostos aos mesmos determinantes sociais e ambientais que aumentam a suscetibilidade para anemia, as restrições alimentares ocasionadas por condições socioeconômicas e demográficas desfavoráveis têm maior impacto nas mães, em virtude da maior necessidade orgânica de ferro da mulher em idade fértil e provável proteção e cuidado das mães para com os filhos. Indica também que independente da condição socioeconômica, a alimentação inadequada da criança torna-a mais susceptível à anemia. Tais resultados podem estar atrelados também a um efeito positivo do Programa Nacional de Suplementação de Ferro, embora apenas um quarto das crianças de 6 a 24 meses tivesse recebido ferro nos últimos seis meses, o que indica a necessidade de melhorias na operacionalização do programa. / Introduction: Anemia an iron deficiency, is the most frequent and worrisome nutritional deficiency from the standpoint of public health. It mainly affects children, pregnant women and women of childbearing age. Despite the intervention measures for prevention and control of anemia in Brazil, studies shows that prevalence rates are high. Objective: Investigate the situation of anemia and its determinants in mothers and children in Brazil, considering the family context. Method: Quantitative cross-sectional survey, that used the database of the national survey of demography and health of women and children (PNDS) 2006. This information was collected through two questionnaires, with basic information about the home and its residents and also detailed information about the target audience women between 15 to 49 years and children under 5 years. The study evaluated approximately 15.000 women and 5.000 children, with a representative sample of five brazilian regions in urban and rural context. Approximately 40% of households had been selected for blood sampling of women, and all children born from January 2001 had the blood sampling taken provided they were biological children of the interviewees. Hemoglobin analysis was performed in 5.915 women and 4.558 children. This study looked at 1.476 pairs, considering the mother and only one children. The Statistical Package Program for Social Science (SPSS version 18.0) was used for data analysis, which examined anemia in mothers and/or children, mothers and children separately and consisted of univariate and multiple steps. Results: The occurrence of anemia was 36.8% in mothers and/or children, 23.4% of mothers and 17.0% in children. Mothers were 1.49 times more likely to have anemia than children, there was no association between anemia in mothers and children (p=0.478 ). In multiple regression analysis, mothers and/or children residing in the Northeast and Midwest had odds 2,24 and 1,70 times higher, respectively, in relation to the south; the chance was also statistically higher (1,78 times) for those with food insecurity and those in which the mother held a puerperal consultation (1,39 times); primiparity shown as protective factor. Anemia in mothers was also associated with the region of residence, with 2,39 times more chances for the Northeast than in mothers in the South; mothers with food insecurity, who performed a puerperal consultation and had at least one disease, also were 50% more likely to have anemia. In children, anemia was associated with insecurity and food consumption, and those who ate a mixture of water and fresh milk in the last 24 hours had a chance (2,49 and 1,69 times) to be more likely to develop anemia, respectively, as well as children who did not eat an afternoon snack on the last day and ate rice 4 times less in the week (odds 1,57 and 2,38 times higher for anemia, respectively), maternal primiparity proved to be a protector factor. Conclusions: The occurrence of anemia in mothers and/or children is higher in less develop macro-regions and among families with food insecurity, highlights the social causes of nutritional deficiency. It is more frequent in mothers and not associated with anemia in children. In mothers, anemia is associated with socioeconomic, demographic and food insecurity. In children, anemia is associated only with insecurity and food consumption. This result indicates that although there is evidence of mothers and children are exposed to the same social and environmental causes that increase susceptibility to anemia, dietary restrictions and their nutritional consequences caused by unfavorable demographic and socioeconomic conditions will have a greater impact on mothers, owing to the greater need for organic iron in women of childbearing age and protection and care of their mothers to the children. It also indicates that regardless of socioeconomic status, whether the childs diet is inadequate, it will be more susceptible to anemia. The results can be linked also to a positive effect of the National Iron Supplementation, although only one quarter of children aged 6 to 24 months had received iron in the last six months, which indicates the need for improvements in the operation of the program.

Introdução: Anemia é um importante problema de saúde pública no Brasil, ainda muito associado às condições sociais. A fortificação de alimentos com ferro é uma alternativa de grande alcance no combate à deficiência de ferro e controle da anemia, pois representa uma fonte complementar que contribui para a formação de reservas do mineral para os períodos de maior vulnerabilidade. As gestantes compõem um dos grupos mais vulneráveis à anemia, com consequências deletérias à sua saúde e do feto. Considerando que a fortificação compulsória das farinhas de trigo e milho com ferro foi efetivamente implantada em junho de 2004, supõe-se que mulheres em idade reprodutiva tenham aumentado suas reservas, tornando as gestações de menor risco. Justifica-se, assim, avaliar o efeito da fortificação das farinhas no controle da anemia em gestantes. Objetivo: Avaliar o efeito da fortificação das farinhas de trigo e milho com ferro, no controle da anemia em gestantes atendidas em serviços públicos de pré-natal, localizados em municípios das cinco regiões do Brasil. Métodos: Estudo de avaliação de intervenção por meio de painéis repetidos, com amostras transversais independentes, realizado em serviços públicos de saúde localizados em municípios das cinco regiões do Brasil. Foram coletados dados retrospectivos de 12.119 prontuários de gestantes distribuídas em dois grupos: Antes-fortificação (parto antes de Jun/2004) e Após-fortificação (última menstruação após Jun/2005). Anemia foi definida como Hb<11g/dL. Níveis de hemoglobina-Hb por idade gestacional foram avaliados segundo critérios do Center for Disease Control-CDC (1989) e Szarfarc et al. (1983). Utilizou-se teste qui-quadrado, t de Student e regressão logística, com nível de significância de 5%. Resultados: Na amostra total, a anemia diminuiu de 25% para 20% após a fortificação (p<0,001), com aumento das médias de Hb (p<0,001). Verificaram-se, entretanto, diferenças regionais importantes. Nas regiões Nordeste e Norte, onde as prevalências eram elevadas, houve queda significativa Após-fortificação: de 37% para 29% e de 32% para 25%, respectivamente. Nas regiões Sudeste e Sul, cujas prevalências eram baixas mesmo antes da fortificação, também houve redução: de 18% para 15% e de 7% para 6%, respectivamente. Nas regiões Sudeste e Sul, as gestantes tinham, respectivamente, razão de chance 30% e 75% menor de serem anêmicas, em relação às da região Nordeste. Em comparação com os parâmetros do CDC (1989), os níveis de Hb segundo idade gestacional de ambos os grupos se mostraram discretamente mais elevados nos primeiros meses, porém bem mais baixos após o 4º mês. O mesmo se verificou em relação à curva de Szarfarc et al (1983), porém após o 3º mês, as médias de Hb das gestantes estudadas acompanharam essa curva. Mesmo após o controle das variáveis que se mostraram diferentes entre os grupos (p<0,20), o grupo Após-fortificação apresentou menor razão de chance de ter anemia. Análise de regressão logística mostrou que grupo, região geográfica, situação conjugal, trimestre gestacional, estado nutricional inicial e gestação anterior associaram-se com anemia (p<0,05). Conclusões: Apesar de a prevalência da anemia em gestantes continuar elevada nas regiões Nordeste, Norte e Centro-Oeste, a diminuição no total da amostra e aumento das médias de Hb sugerem efeito positivo da fortificação das farinhas no controle da deficiência do mineral, embora outras variáveis não estudadas possam ter contribuído para tal resultado. A distribuição desigual da anemia nas diferentes regiões geográficas do Brasil, entretanto, reitera sua determinação social. Considerando as dificuldades na obtenção dos dados de Hb a partir de prontuários, sugere-se a implantação de um sistema de monitoramento permanente que possibilite acompanhar a evolução da anemia gestacional em resposta às estratégias implementadas. / Introduction: Anemia is an important public health problem in Brazil, and it has been quite associated to social conditions. Food fortification with iron is a far-reaching alternative to combat iron deficiency and anemia control, as it represents an additional source that contributes to the formation of the mineral stores for the periods of greatest vulnerability. Pregnant women are one of the most vulnerable to anemia, with deleterious consequences to their health and the fetus. Whereas the mandatory fortification of flour and corn flour with iron was effectively implemented in June 2004, it is assumed that women of reproductive age have increased their reserves, making lower-risk pregnancies. Therefore, it justified to evaluate the effect of flour fortification in the control of anemia in pregnant women. Objective: To evaluate the effect of fortification of wheat and corn flours with iron in the control of anemia in pregnant women attending public prenatal care, located in cities of the five regions of Brazil. Methods: A repeated cross-sectional panel evaluation study of intervention was carried out in public health care services located in cities of the five Brazilian regions. We collected backward data in 12.119 medical records. Pregnant women were divided into two groups: Before-fortification (delivery before Jun/2004) and After-fortification (last menstrual period after Jun/2005). Anemia was defined as Hb<11g/dL. Hb level by gestational age was evaluated according to criteria of Centers for Disease Control-CDC(1989) and Szarfarc et al(1983). We used chi-square, Students t test and logistic regression, with significance level of 5%. Results: In the total sample, anemia was dropped from 25% to 20% after fortification (p<0.001). Hb level also was significantly higher after fortification (p <0.001). However, the findings showed great differences among the regions. In the Northeast and North, where the prevalence of anemia were high, significant drop After-fortification was found: from 37% to 29% and 32% to 25%, respectively. In the Southeast and South, whose prevalences were low Before-fortification, also decreased: from 18% to 15% and 7% to 6%, respectively. In the Southeast and South, the women had, respectively, odds ratio 30% and 75% less to be anemic compared to the Northeast. Hb levels according to gestational age, comparing to CDC parameters, were better in the first trimester but worse from the 4th month in both groups. The same was verified comparing to curve of Szarfarc et al, but Hb levels of pregnant women studied followed this curve after 3rd month. Even after controlling for variables that were different between groups (p <0.20), the group After-fortification had lower odds ratio of having anemia. Logistic regression showed that group, geographic region, marital status, gestational trimester, initial nutritional status and previous pregnancy were associated with anemia (p<0.05). Conclusions: Despite the prevalence of anemia in pregnant women is still high in the Northeast, North and Midwest, the decrease in the total sample and increase in Hb levels suggest positive effect of fortification of flour to the control of iron deficiency, although other variables not studied may have contributed to this result. The unequal distribution of anemia in different geographical regions of Brazil, however, reiterates its social determination. Considering the difficulties in obtaining data of Hb from medical records suggest the establishment of a permanent monitoring system allows monitoring the evolution of pregnancy anemia in response to the strategies implemented.

Einleitung: Eisenmangel ist ein häufiges Problem bei Ausdauersportlern, da dieser die Leistungsfähigkeit einschränken und zu einer Blutanämie führen kann. Von den klassischen Eisenstoffwechselparametern sind nur wenige geeignet, den tatsächlichen Eisenstatus anzuzeigen, da sie durch sportliche Aktivität per se beeinflusst werden können. In der Studie wird die Wertigkeit moderner Eisenstoffwechselparameter im Ausdauersport untersucht. Ergebnisse und Diskussion: Der Hämoglobingehalt der Retikulozyten (CHr) und der prozentuale Anteil der hypochromen Erythrozyten (% HYPO) bleiben als moderne Parameter der Eisenstoffwechseldiagnostik auch nach regenerativen, extensiven sowie intensiven Ausdauerbelastungen konstant. Sie zeigen somit unbeeinflusst von der (Ausdauer-)Sportart als auch von der Belastungsdauer und –intensität die aktuelle Eisenversorgung der Erythropoese im Knochenmark an. Als Monitoringparameter im Rahmen einer Eisensubstitution sind der CHr sowie der prozentuale Anteil hypochromer Retikulozyten sensible Parameter, mit denen sich schnell und zuverlässig die Effektivität einer oralen Eisensubstitution nachweisen lässt. Der Eisenstatus kann durch die alleinige Bestimmung des CHr bzw. des % HYPO nicht exakt ermittelt werden. Im Gegensatz zum Einsatz bei klinischen Fragestellungen können sie zu diesem Zeitpunkt in der Sportmedizin allenfalls nur ein ergänzender Parameter in der Differentialdiagnostik eines Eisenmangels sein. Die für Ausdauersportler ermittelten Referenzwerte liegen bei 28,8-35,9 pg für den CHr und bei 0-0,5 % für die hypochromen Erythrozyten. Ein belastungsbedingter Anstieg des Eisen-regulierenden Hormons Hepcidin könnte auf Grund seiner inhibitorischen Wirkung auf die intestinale Eisenabsorption sowie auf die Freisetzung von Eisen aus den Makrophagen zur Entwicklung von Eisenmangel-zuständen führen. Die Entwicklung von Hepcidin-Antagonisten könnte in Zukunft therapeutische Anwendungen finden. / Introduction: Athletes are commonly diagnosed with iron deficiency, particularly those involved in endurance sports. It often not only decreases athletic performance but also contributes to the development of anaemia. Many biochemical markers are used to evaluate body iron stores but some of them are affected by physical exercises. This study was designed to investigate new haematological parameters in endurance athletes. Results and discussion: Reticulocyte hemoglobin content (CHr) and percentage of hypochromic red cells (% HYPO) were highly stable in athletes subjected to varying physical loads. Furthermore, they were neither affected by different forms of endurance sports nor by their duration and intensity. These modern indices are able to reflect the availability of iron during erythropoiesis at all times. In the early prediction of response to oral iron supplementation, the reticulocyte indices CHr and % HYPOr (percentage of hypochromic reticulocytes) are the most sensitive parameters. However, it is not possible to assess the iron status in athletes by CHr and % HYPO alone. In contrast to other clinical cases they can only be an additional parameter in the differential diagnosis of iron deficiency. The calculated reference range for endurance athletes are 28,8 - 35,9 pg for CHr and 0-0,5 % for % HYPO. As the iron-regulating hormone hepcidin is inhibiting the absorption of iron from the diet at the site of the duodenal enterocytes and blocking the release of iron from macrophages that have collected senescent erythrocytes, an exercise induced up-regulation of hepcidin activity might potentially be a new mechanism causing iron deficiency in athletes. Therefore, the development of hepcidin antagonists could prove to be helpful with regard to therapeutic utilization.