Assessment of iron stores in children with transfusion siderosis by biomagnetic liver susceptometry.

To investigate the applicability of noninvasive Superconducting Quantum Interference Device (SQUID) biomagnetic liver susceptometry and its limitations in thalassemic children, 23 patients with beta-thalassemia major and other iron loading anemias (age: 4-16 years) and 16 age-related normal children were studied. Liver iron concentrations ranged from 600 to 11,000 microg/g(liver) for thalassemic patients and from 60 to 340 microg/g(liver) for normal patients. Measuring the respective organ volumes by sonography, liver and spleen iron stores, accounting for 80% of total body iron stores, were estimated.

Prevalence of the C282Y and H63D mutations in the HFE gene in patients with hereditary haemochromatosis and in control subjects from Northern Germany.

Mutation analysis was performed for two HFE mutations (C282Y, H63D) in unrelated patients with hereditary haemochromatosis (n = 92), family members of patients (n = 34), and unrelated controls (n = 157) from Northern Germany, 87/92 patients (94.6%) revealed the C282Y mutation in homozygous form, five were heterozygous. No H63D mutation was found in 174 chromosomes of patients homozygous for C282Y, whereas four of the heterozygote patients also carried the H63D mutation.

Iron deficiency in distance runners. A reinvestigation using Fe-labelling and non-invasive liver iron quantification.

In a group of male distance runners, 23 out of 45 athletes showed decreased serum ferritin values (< 35 micrograms). The high prevalence of a typical iron deficiency in runners was confirmed in a subgroup of eight athletes in which the iron metabolism was studied in detail using radio-iron labelling and liver iron quantification. Most of these athletes showed an up-regulated 59Fe absorption and a decreased liver iron concentration as compared to a control group.

Liver iron stores in patients with secondary haemosiderosis under iron chelation therapy with deferoxamine or deferiprone.

Total body iron stores including liver and spleen iron were assessed by non-invasive SQUID biomagnetometry. The liver iron concentration was measured in groups of patients with beta-thalassaemia major or other posttransfusional siderosis under treatment with the oral iron chelator deferiprone (n = 19) and/or with parenteral deferoxamine (n = 33). An interquartile range for liver iron concentrations of 1680-4470 micrograms/g liver was found in these patients.

Bioavailability of iron from oral ferric polymaltose in humans.

The bioavailability or iron from iron(III)hydroxide polymaltose complex (ferric polymaltose, Fe-PM) was studied in human volunteers with normal or depleted iron stores as well as in patients with iron deficiency anemia. From an oral iron dose of 100 mg neutron activated Fe-PM, starved subjects with depleted iron stores absorbed significantly less (p < 0.003) 59Fe (3.

Screening for hereditary hemochromatosis in prospective blood donors.

Prospective blood donors (n = 1,265, mean age 26 years) were screened for elevated serum ferritin and serum iron. Final diagnosis for hereditary hemochromatosis was made by liver iron concentration (noninvasive biomagnetometry), transferrin saturation, and 59Fe absorption in 3 male subjects. This preliminary result confirms for the first time the current frequency estimation of homozygous hemochromatosis (0.

Performance of Helicobacter pylori acid extract and urease enzyme-linked immunosorbent assays in relation to 14C-urea breath test.

The 14C-urea breath test has been shown to be a reliable non-invasive method to detect the presence or absence of H. pylori infection. Alternatively, a number of techniques have been devised to detect circulating antibodies against H.

Bismuth absorption from 205Bi-labelled pharmaceutical bismuth compounds used in the treatment of peptic ulcer disease.

The absorption of bismuth from five 205Bi-labelled pharmaceutically used bismuth compounds was studied in man. From single oral doses of all compounds under investigation only less than 0.1% bismuth was absorbed and excreted with the urine.

Bioavailability of bismuth from 205Bi-labelled pharmaceutical oral Bi-preparations in rats.

The bioavailability of 205Bi from various 205Bi-labelled pharmaceutical oral bismuth preparations was studied in rats. The intestinal absorption, calculated from 205Bi whole body retention and accumulated 205Bi urinary excretion, was small in general, but significantly higher (0.26-0.

Intestinal absorption of iron from 59Fe-labelled hexacyanoferrates(II) in piglets.

The intestinal absorption of 59Fe and 14C from hexacyanoferrates(II) was studied in piglets. KFeIII[FeII (CN)6] (I) and FeIII4[FeII(CN)6]3 (II) were labelled with 59Fe both in the Fe(III)-position (outside the complex anion, a) or in the Fe(II)-position (hexacyanoferrate anion, b). Labelling of the Fe(III)-position resulted in a 59Fe-absorption of 1.

Chronic experimental iron losses in rats not leading to overt iron deficiency: a model for the regulation of the whole-body iron balance in an iron-replete condition.

Intestinal iron absorption studies, which include investigation of iron deficiency, increased erythropoiesis, low iron diet and acute bleeding, have been done, but none have reported the regulation of the balance of an iron-replete individual. We bled rats at regular time intervals, such that the experimentally induced iron losses were compensated by iron from storage and nutritional procurement without the onset of anemia. During these experimental periods the hemoglobin and plasma iron concentrations were determined along with repeated histochemical gradings of the bone marrow iron.

Proposal for the standardization of the serum unsaturated iron binding capacity assay, and results in groups of subjects with normal iron stores and with prelatent, latent, and manifest iron deficiency.

An effort has been made to standardize the indirect iron saturation excess method for the determination of the serum unsaturated iron binding capacity (UIBC) and thus to relinquish the direct adsorption methods for the assay of the serum total iron binding capacity (TIBC) which give falsely high results due to unspecific binding of the saturating iron to serum proteins. In order to eliminate the interfering effects of hydrolytic polymerization of iron(III) on the saturation of apotransferrin in serum and on the colorimetric determination of the unbound iron excess at pH 8.3, conditions have been studied for the preparation of the iron-nitrilotriacetate-complex (Fe(NTA)2) solution at pH 8.

Enteropancreatic circulation of trypsin in man.

Following the intraduodenal installation of purified 125I-labeled human trypsin up to about 4--6% of the label was measured after 15--30 min in blood plasma and found to separate in a dextran-gel filtration system similar to purified human trypsin (-125I) after incubation with human serum. About 1% of the installed trypsin-(-125I)-dose was found already after 20 min in 100 ml of aspirated pancreatic secretion and later on also in the duodenal content. The results support the concept of the existence of an enteropancreatic circulation of trypsin also in man and explain in part the low to non-detectable levels of immunoreactive serum trypsin observed in patients with exocrine pancreatic insufficiency.

Immunoreactive serum trypsin in diseases of the pancreas.

Immunoreactive serum trypsin was measured with a double antibody radioimmunoassay in normal subjects and patients with various diseases of the pancreas. The normal range is 115-350 ng/ml with a geometric mean of 212 ng/ml. No trypsin was found in serum after total duodenopancreatectomy, in about 75% of patients with cystic fibrosis and in a few patients with pancreas carcinoma or chronic pancreatitis.

[Bioavailability of iron in oral iron preparations. Principles of duration and dosage (author's transl)].

Using 59Fe labeled iron preparations, both the exactly and quantitatively determined absorbability by whole body retention measurement of the absorbed 59Fe and the calculated relative bioavailability from the postabsorption rise in serum iron concentration have coincidently shown that only about half as much Fe (II) is absorbed from oral iron preparations with delayed liberation of iron in the small intestine than from an Fe (II) preparation liberating Fe (II) more rapidly in the stomach. From preparations with trivalent iron only 1/7 to 1/20 of the amount of iron is absorbed which can be absorbed from an Fe (II) preparation with a more rapid rate of Fe liberation. The optimal oral iron therapy is therefore with aqueous solutions of Fe (II) or Fe (II) preparations which disintegrate immediately in the stomach.

Iron absorption from hemiglobin (stable oxidation product of hemoglobin) in relation to the dose in subjects with normal and depleted iron stores.

The dose relationship of hemiglobin iron absorption has been investigated in subjects with normal and depleted iron stores and was found to fit a linear regression in a bilogarithmic presentation of hemiglobin iron dose and iron absorption. Identical regression coefficients but different intercepts of regression were estimated for subjects with normal and depleted iron stores indicating a constant proportional increase of hemiglobin iron absorption in subjects with depleted iron stores in the full dose range of 0.10-50 mg hemiglobin iron.