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Query: UMLS:C0240066 (iron deficiency)
 7,156 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Rats of Wistar strain, of same age, were kept on iron free diet up to nearly absolute iron deficiency in iron depots. Afterwards granuloma was produced by implantation of cotton pellets subcutaneously. For characterization of the collagen biosynthesis in the granuloma the neutral salt soluble collagen and the activity of the prolyl hydroxylase were measured in the granuloma 4, 8 and 12 days after cotton pellet implantation. At the same time "collagen-like" protein was determined in the serum of the animals. The enzyme activity was statistically significant lower in the granuloma of animals on iron deficiency than in the granuloma of the comparable groups on normal diet. Statistically significant higher concentration of neutral salt soluble collagen was found 8 and 12 days after cotton pellet implantation in the group on iron free diet. There was no significant difference as to the serum levels of "collagen-like" protein in serum.
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PMID:[Parameters of collagen biosynthesis in cotton pellet granuloma of rats on iron deficiency (author's transl)]. 21 Apr 87

Free iron in the circulation in contrast to iron complexed with protein or carbohyrdate, is intensely toxic. The annual morbidity and mortality from accidental overdose with iron salts is significant and has directed attention to the evaluation of safer forms of therapy. Comparative studies between oral ferrous sulphate and iron polymaltose in rats established an LD100 of 350 mg/kg for the salt, whereas neither morbidity nor mortality could be produced in doses exceeding 1 000 mg/kg for the complex. Bio-availability of iron from salt and complex for haemoglobin synthesis was then compared both in rats and in man with a twin-isotope technique. In experimental animals and in the human studies, venesected individuals were used to reproduce the iron deficiency state where treatment would be indicated. It was concluded that bioavailability is comparable for therapeutic doses of ferrous sulphate and iron polymaltose in iron-deficient subjects. The marginally lower absorption of complex was offset by a greater degree of gastrointestinal tract tolerance; the wide margin of safety may be of importance in reducing the danger of accidental iron overdose.
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PMID:Absorption of iron polymaltose and ferrous sulphate in rats and humans. A comparative study. 47 64

Almost all segments of the gastrointestinal tract have been used as urinary tract substitutes. The specific nutritional and gastrointestinal complications depend on the particular portion of bowel that is removed from the alimentary tract. The use of stomach theoretically may predispose the patient to hypergastrinemia and peptic ulcer disease, hypocalcemia, and iron deficiency or megaloblastic anemia. Resection of a large amount of jejunum causes malabsorption. Limited use of colon segments usually is well tolerated, but loss of large parts of the colon directly decreases available absorptive area, resulting in diarrhea. Resection of the ileum and ileocecal valve can lead to several disease states. One is mixed secretory-osmotic diarrhea. Decreased ileal reabsorption of bile salts results in fat malabsorption and steatorrhea. The presentation of increased amounts of bile salts and fatty acids to the colon decreases water absorption and stimulates active chloride and water secretion, producing a cholera-like high-volume secretory diarrhea. The loss of the ileocecal valve and ileum segment accelerates intestinal transit time, which does not allow for complete digestion and absorption of food. Water and electrolytes remain associated with undigested food particles and may overwhelm the absorptive capacity of the colon, resulting in an osmotic diarrhea. A second problem is vitamin B12 deficiency. Surgical reduction of sites in the terminal ileum for active and exclusive uptake of vitamin B12 might lead to hypovitaminosis. If this is unrecognized, patients may develop irreversible neurologic injury. A third problem is cholelithiasis. Derangements in bile salt metabolism can occur when as little as 10 cm of ileum is resected, and the propensity to form gallstones is increased. Pigment gallstones appear to be the predominant stone associated with ileal resections. The fourth possible problem is urolithiasis, the etiology of which is multifactorial in patients with ileal resections. With decreased availability of bile salts, fat malabsorption occurs. Fatty acids bind with calcium and magnesium to form soaps, resulting in increased levels of free oxalate available for absorption. Moreover, fatty acids directly increase colonic permeability to oxalate.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Nutritional and gastrointestinal complications of the use of bowel segments in the lower urinary tract. 194 6

For many decades there has been adequate information for the elimination of acute dietary deficiency diseases. Scurvy, beri-beri, and pellagra, once serious scourges, are now seen only rarely. The severe forms of protein-energy malnutrition, kwashiorkor and marasmus, have also decreased greatly. Nonetheless, mild to moderate forms of protein-energy deficiency, exacerbated by infection, continue to impair growth and development in a majority of the low-income pre-school age populations of most developing countries. Deficiencies of iron, iodine, and vitamin A are still widespread in developing countries. Fortunately, the success of the WHO/UNICEF "Child Survival and Development Revolution" in persuading most developing countries to introduce expanded programs of immunization, growth monitoring, and appropriate feeding of young children, control of diarrheal disease, and specific campaigns against avitaminosis A, iodine deficiency disorders, and the functional consequences of iron deficiency, will accelerate the decline of acute deficiency diseases in the developing world. Diets are changing among the more affluent in these countries, however, and it is time for them to stress dietary goals for the health of rich and poor alike. For the first time there is enough information regarding dietary risk factors for chronic disease to provide an opportunity in the 1990s to accelerate the dietary changes that have already brought significant health benefits to some populations in North America and Europe. The changes, which include a lower dietary intake of fat, particularly saturated fat, less salt, and more green and yellow vegetable and whole grain cereals, can be expected to influence favorably morbidity from cardiovascular diseases and some kinds of cancer. For maximum benefit, these measures need to be combined with the avoidance of obesity, reasonable physical activity, abstention from, or moderate use of, alcohol, and avoidance of tobacco in any form. Since there is already considerable momentum toward these changes in North America and some European countries, the 1990s are likely to see substantial further progress in the reduction of chronic diseases known to be influenced by diet.
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PMID:Nutrition: prospects for the 1990s. 219 71

The formulation of an oral iron tablet may influence its therapeutic efficacy in correcting iron deficiency. In order to determine the oral iron preparations patients in a Canadian urban center were receiving, a questionnaire was circulated to family physicians, internists, surgeons, and obstetrician-gynecologists to determine their prescribing practices. A survey of pharmacies in the city was also conducted to determine which brand of each iron salt (sulfate, gluconate, fumarate) they dispensed for a generic oral iron prescription. Most physicians (74 percent) chose ferrous sulfate as their drug of first choice. The majority of prescribers would not specifically request either enteric-coated/slow-release or nonenteric-coated preparations as first or second choices (71 and 64 percent, respectively). Enteric-coated or slow-release preparations were specified by 10 and 19 percent of physicians as first and second choices, respectively. Most pharmacies (96 percent) dispensed an enteric-coated preparation of ferrous sulfate for a generic prescription. We believe that many patients are receiving iron tablets with altered release properties (enteric-coated/slow-release). These tablets may fail to provide the desired therapeutic benefit based on the known physiology of iron absorption.
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PMID:Prescribing and dispensing practices for oral iron tablets: a Canadian experience. 226 Mar 48

In both experimental animals and human subjects iron absorption over a wide dosage range was quantitatively equivalent from ferrous salts and a ferric polymaltose complex under basal conditions. The comparable bioavailability was maintained when demand was increased by iron depletion or erythroid stimulation and depressed by expansion of body stores or impaired erythropoiesis. This common pattern for iron retention from both salt and complex supports the interchangeable use of these products in therapy of absolute iron deficiency.
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PMID:Equivalent bioavailability of iron from ferrous salts and a ferric polymaltose complex. Clinical and experimental studies. 356 65

A young woman was referred for nephrologic evaluation of hypertension and a curious desire for table salt. Suspicion of iron-deficiency anemia arose only after it was determined that sodium balance was achievable during supervised sodium restriction. This salt craving abated within 2 weeks of initiation of iron replacement therapy. Although pica is a common manifestation of iron deficiency, this appears to be the first reported case of salt pica secondary to iron deficiency.
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PMID:Sodium chloride pica secondary to iron-deficiency anemia. 396 72

Severe copper deficiency was induced in rats by rearing nursing dams and their offsprings on a semisynthetic diet comprising all the requisite nutrients and trace metals except copper. The copper-deprived rats exhibited growth retardation, severe anaemia, loss of caeruloplasmin, decrease of cytochrome oxidase, accumulation of salt-soluble collagen and a drastic decrease in iron in plasma and liver. Apart from these characteristic signs of deficiency, a marked inhibition of protein synthesis was found to occur both in vivo and in cell-free liver preparations. The curtailed ability to carry out endogenously coded amino acid incorporation into protein contrasted with the unimpaired poly(U)-acid-directed phenylalanine polymerization. This inhibition pattern, as well as the attendant disaggregation of the liver polyribosomes, suggested that the primary biosynthetic lesion was located at the stage of peptide-chain initiation. Concurrently with this alteration there was a pronounced depletion of the hepatic ATP content, associated with a parallel depression of mitochondrial respiration and an enhancement of ATPase activity. Supplementation of the copper-deficient diet with a 2-4-fold excess of iron (relative to the standard diet) prevented growth retardation and anaemia and restored normal energy metabolism, as well as unimpaired protein-synthesizing capacity. The conclusion that these disturbances were primarily determined by the secondary iron deficiency was also borne out by the finding that similar alterations occurred in rats maintained on a copper-sufficient but iron-deficient diet. On the other hand, the iron-fortified diet failed to reverse the other signs of copper deficiency, namely the loss of caeruloplasmin, the diminished rate of cytochrome oxidase and the increase of soluble collagen. The interrelations between the various biochemical lesions induced by deprivation of copper or iron are discussed and the possible role of ATP depletion in determining the derangement of protein synthesis is considered.
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PMID:Biochemical lesions in copper-deficient rats caused by secondary iron deficiency. Derangement of protein synthesis and impairment of energy metabolism. 625 58

Iron absorption was directly compared between equivalent doses of ferrous salts and a polymaltose complex using a twin-isotope technique in which each individual acts as his own control. In the first study, bioavailability of iron from ferrous sulfate and the complex was defined at physiologic doses of 5 mg (Group 1: n = 14) and therapeutic doses of 50 mg (Group 2: n = 13). In Group 1, mean absorption from salt was 47.77% (SD 14.58%) and from polymaltose, 46.56% SD 17.07%). In Group 2, mean absorption from salt was 32.92% (SD 13.42%) and from polymaltose, 27.07% (SD 6.50%). In a second study, 100 mg of iron in a chewable formulation was used to compare absorption between equal doses of ferrous fumarate and the polymaltose complex. Mean absorption from salt was 10.25% (SD 6.89%) and from polymaltose 10.68% (SD 4.68%). At all three dosage levels, iron is equally available from salt or polymaltose for hemoglobin synthesis (p greater than 0.20), and absorption negatively correlated with plasma ferritin (p less than 0.01). These two materials may be used interchangeably in the treatment of patients with absolute iron deficiency.
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PMID:Oral iron therapy in human subjects, comparative absorption between ferrous salts and iron polymaltose. 659 14

Iron fortification is the optimal approach to reducing the high prevalence of iron deficiency in developing countries. Selection of the iron source entails a compromise between the use of inert compounds which are poorly absorbed and chemically reactive forms with high bioavailability. Although the vehicle and fortification compound must be chosen in tandem because most iron compounds cause discoloration or rancidity, the emphasis in this review is on the food vehicle. Technology for fortifying wheat flour and bread is well established and the use of these vehicles has probably had a significant impact on iron status in Western countries. Recent studies in India indicate that the fortification of common salt is technically feasible and field trials have shown a good hematological response. Similar success has been achieved by fortifying refined sugar with NaFeEDTA in Guatemala. Rice has advantages as a vehicle in those areas where it is the staple food but the technology requires further development. Fish-based condiments have been successfully fortified with NaFeEDTA and show promise as a vehicle in East Asian countries. The fortification of infant foods poses no technical problems and should be encouraged. Additional work is needed to identify other fortification options and to develop targeted fortification programs that will direct iron to those segments of a population in greatest need.
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PMID:Iron fortification: an update. 662 7


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