Search results for "Ferritins"
showing 10 items of 57 documents
Structural and magnetic characterization of Pd nanoparticles encapsulated in apoferritin
2010
Pd nanoparticles exhibiting permanent magnetism at room temperature have been prepared within the apoferritin cavity. Pd nanoparticles in air and under an inert atmosphere were synthesized to study the influence of the aerobic and anaerobic conditions in the final magnetic properties. The surface of nanoparticles as well as the type of crystalline phase could determine the magnetic properties. X-ray powder diffraction, including Debye-function analysis, transmission electronic microscopy, and magnetization measurements have been used for characterizing the nanoparticles.
Low angle neutron scattering of ferritin studied by contrast variation.
1976
Ferritins containing different amounts of iron have been studied by neutron small angle scattering in H 2 O/D 2 O mixtures. Apoferritin has also been studied in solutions of small organic molecules. There is a larger contrast variation in the solutions of small organic molecules than in the corresponding H 2 O/D 2 O experiments from which it may be calculated that I g of apoferritin contains 0·3 g of H 2 O. The solvent composition at zero contrast varies regularly with the iron content of the protein: there is evidence for polydispersity in the iron content of the ferritin used. From analysis of the scattering curves it is concluded that the iron is probably not homogeneously distributed in…
Anaemia during pregnancy as a risk factor for infant iron deficiency: report from the Valencia Infant Anaemia Cohort (VIAC) study.
1990
A prospective cohort study with a 1-year follow-up of 156 neonates was carried out specifically designed to test the hypothesis that there is a positive relationship between iron deficiency during pregnancy and the development of the same disease in newborn infants. Exposure was defined as being born of a mother with ferropenic anaemia at delivery, and cases as the infants who developed iron deficiency during their first year of life. A statistically significant positive association was detected with an odds ratio of 6.57 (95% confidence limits 1.81-25.97). A stratified analysis was also performed to control the effect of potential confounders such as socio-economic variables, feeding pract…
Effect of Caseinophosphopeptides from αs- and β-Casein on Iron Bioavailability in HuH7 Cells
2015
International audience; Two pools of caseinophosphopeptides (CPPs) obtained from αs- and β-casein fractions (α-CPPs and β-CPPs) were characterized. A total of 16 CPPs were identified in the α-CPPs pool, 9 of them derived from αs1-casein and 7 from αs2-casein. A total of 18 CPPs were identified in the β-CPPs pool. Four of the identified CPPs contained the characteristic phosphoseryl-glutamic acid cluster SpSpSpEE. Calcein assay was used to compare the iron-binding capacity of the α- and β-CPPs pools. At the concentration of 12.5 μM CPPs used in the iron bioavailability assays, β-CPPs pools show greater iron-binding capacity than α-CPPs pools. HuH7 human hepatoma cells show many differentiate…
An association between plasma ferritin concentrations measured 48 h after delivery and postpartum depression.
2010
Abstract Context Iron deficiency is the most common nutritional problem experienced by childbearing women, and postpartum depression (PPD) is the most common psychiatric disorder seen during the first year after delivery. The possible link between iron deficiency and PPD is not clear. Objective To evaluate whether iron status 48 h after delivery was associated with PPD. Our hypothesis was that iron deficiency would be associated with PPD. Design This was a prospective cohort study of depression-free women studied in the postpartum period. Setting Women who give birth at obstetric units in several general hospitals in Spain. Participants A subsample of 729 women was included in the present s…
Magnetic Langmuir-Blodgett films of ferritin with different iron contents.
2006
Magnetic Langmuir-Blodgett films of four ferritin derivatives with different iron contents containing 4220, 3062, 2200, and 1200 iron atoms, respectively, have been prepared by using the adsorption properties of a 6/1 mixed monolayer of methyl stearate (SME) and dioctadecyldimethylammonium bromide (DODA). The molecular organization of the mixed SME/DODA monolayer is strongly affected by the presence of the water-soluble protein in the subphase as shown by pi-A isotherms, BAM images, and imaging ellipsometry at the water-air interface. BAM images reveal the heterogeneity of this mixed monolayer at the air-water interface. We propose that the ferritin is located under the mixed matrix in thos…
Localization and Characterization of Ferritin in Demospongiae: A Possible Role on Spiculogenesis
2014
Iron, as inorganic ion or as oxide, is widely used by biological systems in a myriad of biological functions (e.g., enzymatic, gene activation and/or regulation). In particular, marine organisms containing silica structures—diatoms and sponges—grow preferentially in the presence of iron. Using primary sponge cell culture from S. domuncula–primmorphs—as an in vitro model to study the Demospongiae spiculogenesis, we found the presence of agglomerates 50 nm in diameter exclusively inside sponge specialized cells called sclerocytes. A clear phase/material separation is observed between the agglomerates and the initial stages of intracellular spicule formation. STEM-HRTEM-EDX analysis of the agg…
The main cold shock protein of Listeria monocytogenes belongs to the family of ferritin-like proteins
2000
The transfer of the food-borne pathogen Listeria monocytogenes from 30 to 5 degrees C was characterized by the sharp induction of a low molecular mass protein. This major cold shock protein has an isoelectric point at pH 5.1 and a molecular mass of about 18 kDa, as observed on two-dimensional gel electrophoresis (2-DE) pattern. Its N-terminal sequence, obtained from the 2-DE spot, shared a complete sequence identity with a Listeria innocua non-heme iron-binding ferritin. The purification of these ferritin-like proteins (Flp) revealed a native molecular mass of about 100-110 kDa which indicates a polypeptide composed of six 18 kDa-subunits. Northern analysis indicated the presence of a 0.8-k…
Regeneration of the cell wall in protoplasts of Candida albicans. A cytochemical study using wheat germ agglutinin and concanavalin A.
1988
To assess the dynamics of synthesis of the wall by regenerating Candida albicans protoplasts deposition of chitin and mannoproteins were investigated ultrastructurally using wheat germ agglutinin conjugated with either horseradish peroxidase or colloidal gold, and Concanavalin A coupled to ferritin respectively. Freshly prepared protoplasts lacked wheat germ agglutinin receptor sites but after 1-2 h of regeneration, they were detected. After 4-5 h of regeneration, the cell wall showed a discrete structure which was only labelled with wheat germ agglutinin in thin sections. At this stage of regeneration the outermost layer of the wall was labelled with clusters of Concanavalin A-ferritin par…
Iron and zinc bioavailability in Caco-2 cells: Influence of caseinophosphopeptides
2013
Abstract A study has been made of the influence of two pools of caseinophosphopeptides (CPPs) obtained from α s - and β-casein (CN) fractions, and of three specific CPPs (β-CN(1–25)4P, α s1 -CN(64–74)4P and α s2 -CN(1–19)4P), on iron bioavailability (ferritin synthesis) and zinc bioavailability (retention, transport and uptake of zinc) in Caco-2 cells. α-CPP and β-CPP pools did not improve ferritin synthesis, but the three specific CPPs showed an increase in ferritin synthesis in Caco-2 cells versus iron sulphate, β-CN(1–25)4P being the most effective. In relation to zinc bioavailability, α-CPPs, β-CPPs, α s1 -CN(64–74)4P and β-CN(1–25)4P increased zinc uptake. However, this increase was of…