Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P02794 (ferritin)
 17,525 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effect of calcium supplement use on iron stores was examined in a randomized controlled study in free-living, healthy, premenopausal women. Of 109 women who completed the study, 52 were in the control group and 57 took two tablets containing 250 mg Ca as the carbonate with each of two meals daily for 12 wk. In all subjects at baseline, plasma ferritin concentrations were positively correlated with heme-iron intake (r = 0.21, P = 0.04), serum iron concentration (r = 0.19, P = 0.04), transferrin saturation (r = 0.31, P = 0.001), and hemoglobin concentration (r = 0.22, P = 0.02), and negatively correlated with total iron-binding capacity (TIBC, r = -0.42, P < 0.001). No significant differences in absolute or percent changes in plasma ferritin concentrations, serum iron concentrations, TIBC, transferrin saturation, hemoglobin concentrations, or hematocrit were observed between the treatment and control groups. Thus, over a 12-wk period, use of 1000 mg Ca as the carbonate daily with meals does not appear to be detrimental to iron stores in healthy, free-living, premenopausal women.
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PMID:Calcium supplementation and plasma ferritin concentrations in premenopausal women. 144 55

Physiologic concentrations of ATP stimulate the translocation of gallium-67 (67Ga) from human transferrin (TF) to horse ferritin (HoFE). The mechanism of this translocation was examined. One millimolar ATP did not speed the binding of 67Ga or indium-111 (111In) to HoFE. ATP and pyrophosphate (PPi) at 1 mM, did not form high affinity complexes with 67Ga or 111In. ATP and PPi interacted directly with the [67Ga]TF complex and could within minutes increase the amount of nonprotein-bound 67Ga. Serum HCO3- concentration, 30 mM, prevented the ATP-induced dissociation of 67Ga from TF, whereas intracellular concentrations (0.4 and 5 mM) did not. Using a dialysis technique, ATP also stimulated the translocation of 111In from TF to HoFE; however, this process was much slower than with 67Ga. ATP caused an increase in the nonprotein-bound 111In compared to the control. These results suggest the formation of nonprotein-bound nuclide by these phosphate-containing compounds in a kinetically labile form is important to the translocation mechanism.
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PMID:Role of phosphate-containing compounds in the transfer of indium-111 and gallium-67 from transferrin to ferritin. 253 83

Effectively, modern research has confirmed Hortega's view of the origin of the microgliacyte from circulating monocytes of the monocyte-macrophage series that invade the brain during embryonic and early postnatal life. Their phagocytic capacity is exercised during the brain remodelling that marks brain maturation. They then convert to the ramified resting microglial cell visualized in the silver carbonate staining technique of Hortega and by modern lectin-binding methods. In response to injury, reactive microglia exhibit hypertrophy and hyperplasia, and may or may not go on to form typical lipid-laden phagocytes. Activated microglia show upregulation of the many marker antigens they share with circulating monocytes, including the major histocompatibility class (MHC) class II antigens that bespeak their immunocompetent nature. However, MHC class I and II expression and development of immunohistochemical positivity for cytoplasmic and plasma membrane antigens that characterize the monocyte-macrophage do not necessarily indicate an immunological response though there is ample evidence that microglia can serve as antigen-presenting cells. Rather, microglia are extraordinarily sensitive to changes in the brain microenvironment, whatever the nature of the exciting mechanism or substance. They may be considered to serve an ever alert, protective and supportive function that can be assembled rapidly to deal with infections, physical injuries, physiologic changes and systemic influences. In addition to elaboration and secretion of cytokines with varied actions, e.g., suppression of astrogliosis, they secrete factors, including nerve growth factor, which are supportive of neurons. They have an important role in iron metabolism and the storage of iron and ferritin. They may promote central nervous system regeneration. They are prominently involved in such pathologic processes as the acquired immunodeficiency syndrome, multiple sclerosis, prion diseases and the degenerative disorders, e.g., Alzheimer's disease and Parkinson's disease. With aging, they grow more numerous, become richer in iron and ferritin and exhibit phenotypic alteration, e.g., the expression of MHC class II antigens that are not ordinarily demonstrable immunohistochemically in the resting state. The rate of growth of our knowledge of microglia during the last decade has been exponential and continues.
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PMID:The microglial cell. A historical review. 884 46

In this study, we examined the cord serum erythropoietin (EPO) level in newborn infants in relation to venous cord blood gases and iron status markers (cord serum ferritin, cord serum transferrin saturation). The subjects were 90 healthy newborn term infants with a normal birth and 90 healthy women with an uncomplicated pregnancy and delivery. Within 14-18 weeks of gestation, 47 prospective mothers, allocated at random, received tablets containing 66 mg ferrous iron daily, and 43 received a placebo. Serum EPO was measured in women prior to delivery. Serum EPO, serum ferritin and serum transferrin saturation were analyzed in cord blood from the newborn. Blood gases (PO2, PCO2 and standard HCO3, PH) were measured in venous cord blood and Apgar scores were recorded. The cord serum EPO level in the newborn was not significantly affected by the iron supplementation to the mothers. In the entire series, the geometric mean cord serum EPO was 36 U/I, (median 32 U/I, 5-95% 16-150, range 12-380). There was no correlation between cord serum EPO and APgar score, cord blood PO2, PCO2, standard HCO3 and pH. In the newborn of placebo-treated mothers, log cord serum EPO was inversely correlated with log cord serum ferritin (r = -0.54, P < 0.0002) and cord serum transferrin saturation (r = -0.39, P < 0.011), suggesting that iron deficiency may occur in this newborn group.
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PMID:Cord serum erythropoietin in 90 healthy newborn term infants: relationship to blood gases and iron status markers. 892 81

Calcium has been shown to inhibit iron absorption. The consequences of chronic calcium supplementation on iron status are unclear, however. As part of a randomized calcium-supplementation trial in lactating and nonlactating women in the postpartum period, we determined whether long-term calcium supplementation and lactation status affected iron stores as measured by serum ferritin concentrations. Subjects (95 lactating and 92 nonlactating) were enrolled at approximately 6 mo postpartum and then randomly assigned to receive either 500 mg Ca as calcium carbonate or a placebo twice daily with meals for 6 mo. Lactating women weaned their infants approximately 2 mo after enrollment (ie, approximately 8 mo postpartum). Calcium supplementation had no effect on serum ferritin concentrations. At the end of the study, geometric mean serum ferritin concentrations were 28.4 microg/L in the calcium-supplemented group and 27.5 microg/L in the placebo group (P > 0.5). Lactation status was significantly related to serum ferritin concentrations. At baseline, serum ferritin concentrations were higher in lactating women than in nonlactating women (47.7 compared with 31.5 microg/L, P < 0.001). In lactating women, serum ferritin concentrations decreased by a mean of 17 microg/L after weaning. By 12 mo postpartum, mean serum ferritin concentrations in women who were previously lactating were not significantly higher than those of nonlactating women (30.5 compared with 25.5 microg/L). These findings provide reassurance that long-term calcium supplementation does not impair iron stores. Furthermore, lactation status should be considered when assessing iron nutriture of women and determinants of iron status in populations.
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PMID:Effects of calcium supplementation and lactation on iron status. 962

The short-term effect of calcium supplements (1200 mg Ca/d) on daily nonheme-iron absorption was measured in 14 healthy adult volunteers by using stable isotope extrinsic labeling and fecal monitoring techniques. Mean (+/- SEM) nonheme-iron absorption from a low-calcium (< 320 mg/d), moderately high-iron (15 mg/d) diet was 15.8 +/- 2.1%, but in the presence of calcium (400 mg/meal) as calcium carbonate, absorption fell significantly to 4.7 +/- 1.4% (P < 0.001). The long-term effect of consuming calcium supplements with meals (1200 mg Ca/d) on body iron (functional and storage iron) was investigated in 11 iron-replete adults over a 6-mo period. An unsupplemented control group (n = 13) was also monitored to correct for any seasonal changes in the biochemical measurements. There were no changes in any of the hematologic indexes, including hemoglobin, hematocrit, zinc protoporphyrin, and plasma ferritin resulting from the calcium supplementation. The results clearly show that long-term supplementation with calcium did not reduce plasma ferritin concentrations in iron-replete adults consuming a Western-style diet containing moderate to high amounts of calcium in most meals.
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PMID:Effect of calcium supplementation on daily nonheme-iron absorption and long-term iron status. 966 89

The purpose of studies was: 1) an evaluation of acid-base balance parameters of capillary blood in the course of CAPD treatment with the correlation analysis between these parameters and indices of CAPD adequacy, dietary intake, nutritional status and selected clinical and laboratory findings, 2) an influence of dialysis solution containing amino acids on capillary acid-base balance. The purpose first was realized in 55 patients treated CAPD up to 24 months, the second one-in 8 CAPD patients. Kt/V, PCR, total creatinine clearance, efficacy number and clinical laboratory scores (Missouri system) were used as CAPD adequacy indices. Dietary intake was evaluated from diet histories. Indices of nutritional status included total body mass, blood concentration of total protein, albumin, Fe, ferritin and cholesterol as well as TIBC. It was shown that compensated metabolic acidosis is the most common finding in patients on CAPD. Acid-base parameters do not depend significantly on Kt/V and total creatinine clearance but there is a negative correlation between HCO3- and PCR as well as between H+ concentration and efficacy number. There is no relationship between dietary intake and acid-base parameters of CAPD patients. The worse acid-base status the greater azotemia and the higher removal of nitrogenous compounds in dialysate. It was confirmed that amino acid dialysis solution deteriorates metabolic acidosis but it can be avoided by the use of oral alkalizating drugs.
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PMID:[Parameters of blood acid: base balance and adequacy of continuous ambulatory peritoneal dialysis as well as dietary intake and nutritional status]. 1039 Oct 54

The objectives of this study were to compare iron availability from commercial preparations of FeSO(4), ferrous gluconate, ferrous fumarate, and a polysaccharide-iron complex using an in vitro digestion/Caco-2 cell culture model. In addition, we sought to determine if calcium carbonate and calcium acetate (common phosphate binding agents) inhibited iron availability from an oral iron supplement when digested simultaneously. Caco-2 cell ferritin formation following exposure to simulated gastric and intestinal digests of the iron supplements was used as a measure of iron uptake and availability. Plates without cell monolayers were included in each replication of the experiment to measure the total amount of soluble iron that resulted from the in vitro digestion. Significantly more iron was taken up from the FeSO(4), ferrous gluconate, and ferrous fumarate than the polysaccharide-iron complex. Similar results comparing FeSO(4) and the polysaccharide-iron complex have been observed in humans. In addition, less iron was taken up from digests with calcium carbonate relative to calcium acetate even though similar amounts of soluble iron were observed in these experiments. The results indicate that when iron supplements and phosphate binders are consumed simultaneously, calcium acetate may be the preferred phosphate binder to maximize iron availability.
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PMID:A comparison of iron availability from commercial iron preparations using an in vitro digestion/Caco-2 cell culture model. 1071 89

Iron balance is regulated in part by the level of iron absorption, which is influenced by iron stores and the level of erythropoietic activity. In short-term absorption studies, dietary calcium and supplemental doses of calcium chloride or calcium carbonate inhibited iron absorption from concomitantly consumed meals. In contrast, several long-term intervention studies of the effect of calcium supplementation on iron status in populations at potentially high risk for compromised iron status failed to show reductions in various indicators of iron status including serum ferritin levels. The evidence suggests that long-term consumption of calcium supplements does not affect overall iron status. An adaptive response, possibly involving an upregulation in the efficiency of iron absorption, has been suggested as a possible explanation for the disparity between the results from short- and long-term studies.
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PMID:Calcium supplementation and iron status of females. 1116 88

The iron storage protein, apoferritin, has a cavity in which iron is oxidized and stored as a hydrated oxide core. The size of the core is about 7 nm in diameter and is regulated by the cavity size. The cavity can be utilized as a nanoreactor to grow inorganic crystals. We incubated apoferritin in nickel or chromium salt solutions to fabricate hydroxide nanoparticles in the cavity. By using a solution containing dissolved carbon dioxide and by precisely controlling the pH, we succeeded in fabricating nickel and chromium cores. During the hydroxylation process of nickel ions a large portion of the apoferritin precipitated through bulk precipitation of nickel hydroxide. Bulk precipitation was suppressed by adding ammonium ions. However, even in the presence of ammonium ions the core did not form using a degassed solution. We concluded that carbonate ions were indispensable for core formation and that the ammonium ions prevented precipitation in the bulk solution. The optimized condition for nickel core formation was 0.3 mg/mL horse spleen apoferritin and 5 mM ammonium nickel sulfate in water containing dissolved carbon dioxide. The pH was maintained at 8.65 using two buffer solutions: 150 mM HEPES (pH 7.5) and 195 mM CAPSO (pH 9.5) with 20 mM ammonium at 23 degrees C. The pH had not changed after 48 h. After 24 h of incubation, all apoferritins remained in the supernatant and all of them had cores. Recombinant L-ferritin showed less precipitation even above a pH of 8.65. A chromium core was formed under the following conditions: 0.1 mg/mL apoferritin, 1 mM ammonium chromium sulfate, 100 mM HEPES (pH 7.5) with a solution containing dissolved carbon dioxide. About 80% of the supernatant apoferritin (0.07 mg/mL) formed a core. In nickel and chromium core formation, carbonate ions would play an important role in accelerating the hydroxylation in the apoferritin cavity compared to the bulk solution outside.
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PMID:Fabrication of nickel and chromium nanoparticles using the protein cage of apoferritin. 1296 75


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