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)

In the present study, we have evaluated the relationship between serum ferritin (SF) levels, 'hemochromatosis allele(s)', blood transfusions and iron parenteral administration in 69 hemodialysis patients. We demonstrated significantly higher SF levels in patients with hemochromatosis allele(s) (HA+) than in patients without hemochromatosis alleles (HA-). In addition, HA+ patients who had received blood transfusions up to 15 months prior to the study had SF levels even higher than those without blood transfusions. On the other hand, HA- patients had normal levels of SF, independent of blood transfusions. After intravenous administration of 1 g iron saccharate, SF levels were significantly higher only in HA+ transfused patients. In conclusion, our study demonstrated that HA+ patients are at a higher risk of iron overload and therefore the use of transfusional and/or parenteral iron should be strictly limited.
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PMID:Risk of iron overload and 'hemochromatosis allele(s)' in patients on maintenance hemodialysis. 357 71

Primary hemochromatosis is a genetic disorder rarely recognized in childhood; its long-term consequences include cirrhosis and liver cancer. We report a family with primary hemochromatosis affecting three generations, including a 7-year-old child and a 29-month-old child; these are the youngest children with primary hemochromatosis yet reported. The pathophysiology, genetics, and clinical findings of this disorder are reviewed. Serum ferritin and transferrin saturation are useful screening tests; definitive diagnosis, however, depends on determination of hepatic iron content. A plan for evaluating and treating affected patients is proposed. Physicians caring for children must learn to recognize this potentially treatable disorder.
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PMID:Primary hemochromatosis in childhood. 365 74

In the attempt to define the abnormalities responsible for the severe iron overload found in patients with idiopathic hemochromatosis (IH) we analyzed, in 8 patients with IH and in 7 normal subjects, by using specific cDNA probes, the genes coding for the main iron-related proteins, i.e., transferrin, transferrin receptor, as well as H and L subunits of ferritin. In all the patients tested all the probes failed to evidentiate rearranged bands with any of the restriction enzymes employed. These findings suggest the absence of gross structural alterations of the genes examined. The lack of polymorphic sites recognized by the restriction enzymes employed in this study within or around the genes examined does not allow to associate a specific gene with the disease.
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PMID:Analysis of the genes for transferrin, transferrin receptor as well as H and L subunits of ferritin in idiopathic hemochromatosis. 367 94

Recent evidence suggests that the hepatic iron-loading characteristic of hemochromatosis may result in part from efficient hepatic clearance of non-transferrin-bound iron, which is increased in this disorder. However, this hypothesis assumes that hepatic clearance remains highly efficient despite excess iron stores. We therefore studied hepatic uptake of non-transferrin-bound iron in the single-pass perfused rat liver under varying conditions. Animals were iron loaded or depleted by dietary manipulation, but no changes in the efficiency of ferrous iron uptake or the kinetic parameters were seen (single-pass extraction, 59-74%; Km, 16-19 microM; Vmax, 30-32 nmol X min-1 X g liver-1). Added divalent zinc, cobalt, and manganese ions reversibly inhibited ferrous iron uptake and the inhibition by zinc was shown to be competitive. Uptake required calcium, was markedly temperature-sensitive (delta E = 14.3 Kcal/mol), and was relatively insensitive to inhibition of cellular energy metabolism. Particles consistent with ferritin cores were seen in lysosomes of hepatic parenchymal cells within 30 min of perfusion with ferrous iron. These results suggest that ferrous iron is cleared from plasma by a passive, saturable transport process that is not regulated by the iron content of the liver and that may be shared with other transition metal ions. Because clearance is highly efficient, increased levels of non-transferrin-bound iron in plasma may present the liver with an obligatory iron load resulting in progressive accumulation and toxicity.
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PMID:Characterization of non-transferrin-bound iron clearance by rat liver. 373 37

The amounts of phosphorus and iron in various isolated ferritin preparations were investigated by: chemical analysis on ferritin samples and electron probe X-ray microanalysis on ferritin particles from the same preparations. A high correlation was found between iron to phosphorus ratios obtained by both methods. Further investigation by electron probe X-ray microanalysis on lysosomes of hepatic cells of patients with idiopathic and secondary hemochromatosis revealed lysosomal iron to phosphorus ratios which were very similar in all parenchymal cells but different from ratios obtained in Kupffer cells. Lysosomal iron to phosphorus ratios in hepatocytes did not change after intensive phlebotomy treatment. It is postulated therefore that, during phlebotomy, iron and phosphorus are concomitantly lost from the hepatic lysosomes.
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PMID:Determination of iron to phosphorus ratios of iron storage compounds in patients with iron overload: a chemical and electron probe X-ray microanalysis. 375 38

The presence of iron in gastric and duodenal mucosa was investigated with Perl's stain in endoscopic biopsies from 13 patients with overt primary hemochromatosis, 10 chronic heavy alcohol abusers, and 10 patients with nonulcer dyspepsia. In the primary hemochromatosis patients marked iron deposition was found in cells at the base of glands in the gastric body and antrum in nine cases, and in crypt cells and Brunner gland cells of the duodenum in six. Iron was detected in the lamina propria of the stomach in five and duodenum in four cases. A similar distribution of iron overload, usually of lesser degree, was also observed in five alcoholics. Serum ferritin levels and the degree of gastric and/or duodenal iron deposits did not correlate in either hemochromatosis patients or alcoholics. No gastric or duodenal siderosis was observed in nonulcer dyspepsia cases. The absence of gastric and duodenal stainable iron in some hemochromatosis patients and its presence in some alcoholics suggests that the diagnostic value of upper gastrointestinal biopsy in primary hemochromatosis is limited.
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PMID:Stainable iron in gastric and duodenal mucosa of primary hemochromatosis patients and alcoholics. 382 30

Under normal conditions, vitamin D absorbed from the diet or synthesized in the skin is transported to the liver where it undergoes hydroxylation. The purpose of this study was to determine whether excess hepatic iron affects this process and the subsequent production of 1,25-dihydroxyvitamin D (1,25-[OH]2D) in the kidney. Mean serum 25-hydroxyvitamin D (25-OHD) concentrations in untreated hereditary hemochromatosis were 13 +/- 6 (SD) in 9 patients with cirrhosis, 13 +/- 6 in 5 patients with hepatic fibrosis, and 22 +/- 6 in 10 patients with normal hepatic architecture aside from siderosis and were significantly lower than the levels found in 24 controls matched for age, sex, and season, p less than 0.05. The mean serum 25-OHD levels in the two groups with hemochromatosis and hepatic damage were significantly lower than the value in the group with normal hepatic architecture, p less than 0.05. Serum 25-OHD levels in individual patients were inversely related to the size of body iron stores as measured by exchangeable body iron, r = -0.64, or serum ferritin, r = -0.47, p less than 0.05. In 15 patients removal of excess body iron by venesection therapy produced a significant increase in the mean serum 25-OHD from 20 ng/ml to 30 ng/ml, p less than 0.05. In contrast, mean serum 1,25-[OH]2D levels were similar in iron-loaded and control subjects, indicating that the regulation of this metabolite was intact in patients with hemochromatosis. The results reveal that the low serum 25-OHD concentration in patients with hemochromatosis is directly related to the extent of iron loading and it is improved by venesection therapy.
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PMID:Low serum 25-hydroxyvitamin D in hereditary hemochromatosis: relation to iron status. 383 88

Erythrocyte and plasma ferritin was followed in 13 patients with iron overload undergoing phlebotomies for at least 6 months in comparison with untreated patients and normal males. Plasma ferritin was widely scattered with an average of only twice the normal, whereas erythrocyte ferritin was highly elevated to about twelve times the normal (p less than 0.0001). - The time course of plasma and erythrocyte ferritin during phlebotomy therapy was analyzed in 3 patients with idiopathic hemochromatosis. Three stages were established: 1. plasma ferritin dropped gradually into the normal range while erythrocyte ferritin remained high, 2. appropriate phlebotomies maintained normal plasma ferritin and high erythrocyte ferritin, and indicated a monthly uptake of dietary iron of 150-200 mg at a steady state, 3. at low plasma ferritin levels, erythrocyte ferritin was rapidly decreased by further intensive phlebotomy therapy. Based on the presumed net removal of iron, 1 microgram/l plasma ferritin was equivalent to 3-6 mg of body iron and 1 microgram/l erythrocyte ferritin to somewhat less than 1 mg of body iron. - An elevated erythrocyte ferritin during phlebotomy therapy in iron overload not only depends on body iron stores like plasma ferritin but may also be regulated by the activity of erythropoiesis.
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PMID:Ferritin in erythrocytes and plasma of patients with iron overload. 384 35

The distribution of ferritin and lysozyme in 19 normal and abnormal duodenal biopsies was studied by an immunoperoxidase technique. The abnormal biopsies included cases of chronic duodenitis with gastric metaplasia, gastric heterotopia, villous atrophy, and a case of hemochromatosis. Ferritin is demonstrated in duodenal absorptive cells, with the staining being most intense in the hemochromatosis case. It was absent in duodenal cells showing gastric metaplasia and in the surface epithelial cells of most biopsies with villous atrophy and gastric heterotopia. Lysozyme-positive mononuclear inflammatory cells were markedly increased in all abnormal biopsies. Not all lysozyme-positive cells were ferritin positive. The latter were especially abundant in areas with gastric metaplasia. It is suggested that this abundance may be related to passive diffusion of intestinal contents, particularly iron, through the metaplastic areas, and consequently there may be a relationship between the presence of duodenal gastric metaplasia and uncontrolled iron absorption.
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PMID:Ferritin and lysozyme distribution in normal and abnormal duodenal mucosae. 389 Dec 62

Acute abdomen, irreversible shock and sudden death are a typical although infrequent complication in patients with hemochromatosis. The author presents a further case of this syndrome and discusses the two leading pathogenetic interpretations described in the literature: sudden release of ferritin, and endotoxin shock. Clinical and post-mortem findings from this patient and a review of 19 cases from the literature suggest that most patients with this syndrome die from a primary bacterial peritonitis with gram negative sepsis and endotoxin shock.
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PMID:[Acute abdomen with irreversible shock, a rare but typical complication of hemochromatosis]. 390 80


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