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

Erythrocytic glutathione-peroxidase (GSH-Px) activity and plasma selenium concentrations were measured in 14 patients: 7 with iron deficiency and 7 with raised serum iron levels. The decreased enzymatic activity in iron deficiency was confirmed. Plasma selenium was significantly lower in patients with lower serum iron; furthermore there is a significant correlation between serum iron and plasma selenium concentrations. Another correlation even more significant was found between plasma selenium and enzyme activity in all the cases we studied. These data suggests that the importance of iron for GSH-Px activity may be merely due to its relationship with selenium and that plasma selenium concentration may be of critical importance for enzyme activity.
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PMID:Erythrocytic glutathione peroxidase: its relationship to plasma selenium in man. 88 36

Studies were made to determine the neutrophil's phagocytosis and bactericidal function in three groups of rats (control, iron deficiency, and iron supplement). Results showed that there were significant differences in values of chemiluminescence (CL) among three groups. The values of peak CL and five minutes integrated CL were markedly decreased in neutrophils of iron-deficient rats, accounting for only 41% and 32% of the control's values respectively. These suggested that the activity of NADPH oxidase was decreased, and the function of respiratory burst of neutrophils was impaired. The activity of myeloperoxidase in the iron-deficient neutrophils was also significantly lower than that in the control cells. It constituted only 30% of the control's value, indicating that the bactericidal function of neutrophils was injured. One week after iron administration, the low values of the peak CL, the five minutes integrated CL and the activity of myeloperoxidase all went up apparently, but not reached the normal levels yet. The time the function of neutrophils in iron-deficient rats returned to normal may be related to the process of neutrophil maturation in bone marrow.
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PMID:[Investigation of impairment of neutrophil's phagocytosis and bactericidal function in rats with iron deficiency]. 166 Aug 47

The influences of iron deficiency on the cochlear iron enzymes and adenosine triphosphatase were studied in 68 iron-deficient rats and 68 control rats (normal and with chronic anemia). A disorderly or topographic distribution and reduction or disappearance of the cochlear succinic dehydrogenase and peroxidase reaction products were found in 37.8% of the rats fed on a basic iron-deficient diet for 14 to 100 days. The activity of cochlear sodium-potassium-dependent adenosine triphosphatase in iron-deficient rats was slightly increased, compared to that in normal controls. These results suggest that iron deficiency would produce significant abnormalities of succinic dehydrogenase and peroxidase activity, which in turn would disturb cell respiration and initiate peroxidative damage to the inner ear cells, result in sensorineural hearing loss, or provide a pathologic basis for cochlear deafness.
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PMID:Changes in the cochlear iron enzymes and adenosine triphosphatase in experimental iron deficiency. 217 94

A Technicon H-1 hematologic analyzer was used to measure the mean leukocyte myeloperoxidase (MPX) in 160 patients seen in a hematology clinic. The normal range was -15 to +10, which included 95% of 300 consecutive hospitalized patients. No abnormalities in the MPX were found in 35 patients with beta-thalassemia minor, 8 with iron deficiency, 14 with myeloproliferative disorders, 17 with autoimmune disorders, and 37 patients with lymphoma in complete remission. On the other hand 36% (10/28) of lymphoma patients with active disease either at diagnosis or relapse had a MPX of greater than 10 compared to only 2.3% (7/300) in hospitalized patients (P less than 0.001). Increased levels of MPX were found primarily in patients with non-Hodgkin's lymphoma (NHL) of intermediate or high grades, or Hodgkin's disease [56% (9/16) compared to only 8.3% (1/12) in those with low grade NHLs, P less than 0.05]. The MPX levels returned to normal after successful treatment. Of the various chemotherapeutic agents used, only hydroxyurea led to a consistent elevation of the MPX. The authors conclude that MPX is commonly increased in patients with lymphoma and in those receiving hydroxyurea. Further studies are required to determine if the MPX is a sensitive test for relapse in patients with lymphomas who had an elevated pretreatment value.
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PMID:The mean leukocyte myeloperoxidase index in hematological patients. 255 19

The polymorphonuclear granulocyte (PMN) kills ingested bacteria by mechanisms that include myeloperoxidase (MPO) and a sudden increase in oxygen consumption (the oxidative burst), both of which are iron dependent. The magnitude of the oxidative burst and activity of MPO were determined in PMNs during the progression of iron deficiency (ID) and following its treatment in rats. As ID developed, the oxidative burst after zymosan activation was less depressed than the activity of MPO. There was no change in the oxidative burst after activation with phorbol myristate acetate (PMA) or in the generation of superoxide (O2-) by NADPH oxidase-containing particles from PMNs. Following iron treatment, impairment of the oxidative burst after zymosan activation was corrected after 1 day. In contrast, the deficit in MPO activity was not corrected until 7 days after initiation of iron treatment. The pattern of recovery in MPO activity after iron treatment corresponded to the prolonged period of maturation of the PMN primary granule since the formation of primary granules, which contain MPO, takes place only in the early, mitotic stages of maturation. The tendency of the PMN to maintain the oxidative burst allows the cell to preserve its capacity for bacterial killing during the progression of iron deficiency.
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PMID:Iron deficiency and neutrophil function: different rates of correction of the depressions in oxidative burst and myeloperoxidase activity after iron treatment. 303 7

We developed a clear-cut nutritional iron deficiency anemia without concomittant malnutrition in rats given a low iron diet, and we restored normal iron and hemoglobin levels in these same animals with iron dextran injections. The neutrophil function studies performed during and after a period of iron deficiency showed the following: Phagocytosis of Staphylococcus aureus 502A, Streptococcus pneumoniae, and Salmonella typhimurium was not altered by iron deficiency or by the administration of iron; phagocytosis of Candida albicans was moderately abnormal during iron deficiency, and became normal with the restoration of iron sufficiency. Microbicidal activity towards Staphylococcus aureus 502A and Candida albicans, two catalase-positive microorganisms, was markedly decreased (to 50% of control values) and returned to normal when iron sufficiency was restored. Killing of a catalase-negative organism, Streptococcus pneumoniae was normal in iron-deficient rats. This pattern of differential bactericidal activities suggested an abnormality of the oxidant radical-generating machinery in neutrophils of iron-deficient animals. Indeed, iron deficiency caused a marked decrease of neutrophil nitroblue tetrazolium dye reduction, which disappeared after iron administration. Neutrophil myeloperoxidase activity was slightly decreased in iron deficient rats and returned to normal after iron administration. Microbicidal activity towards a gram-negative, catalase-positive organism, Salmonella typhimurium, was equal in iron deficient and iron sufficient animals. Our combined results suggest that a definite microbicidal defect is the consequence of nutritional iron deficiency, apart from any protein-calorie malnutrition. This defect affects the disposal in PMNs of two catalase-positive microorganisms (which require intracellular production of oxidant radicals for their destruction) but not of a catalase-negative bacterial species.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Neutrophil bactericidal dysfunction towards oxidant radical-sensitive microorganisms during experimental iron deficiency. 608 85

Studies were performed to determine the effects of iron deficiency in the rat on neutrophil activation and on levels of neutrophil myeloperoxidase and cytochrome b. The period of time required for neutrophil activation was not significantly affected by iron deficiency, but the maximum rates of respiration attained after activation were markedly lower (60% decrease) in iron-deficient neutrophils than in control cells. The myeloperoxidase activity of neutrophils from iron-deficient rats was also markedly decreased (approximately 75%) compared with the activity of control cells; however, the concentration of cytochrome b in the neutrophils was unaffected by iron deficiency.
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PMID:Iron deficiency in the rat: effects on neutrophil activation and metabolism. 633 Jun 57

Iron is essential for the organism. In ionized forms (Fe++, Fe ), it constitutes an integrated part of a lot of different functional proteins (Figure 1). The most important functions are participation in oxygen transport in blood, oxygen storage in muscle tissues and oxidation of nutrients in the mitochondria. Iron is an essential part of cytochrome C and alpha-glycerolphosphate dehydrogenase, and early stages of iron deficiency may, therefore, cause disturbances in tissue metabolism before development of anaemia. Thus, haemoglobin determinations is not very suitable for diagnosing early iron deficiency. The content of iron in roughages, apart from root crops (Table II), is usually sufficient to cover the requirement of domestic animals (Table III), which is met by about 50 mg per kg feed dry matter. Iron deficiency is very often caused by a reduced absorption in the intestinal tract because of components in the feed forming complexes with iron of very low solubility or inhibitors reducing the absorption processes. The immune status of the organism and its resistance against infections depends on the iron supply. Iron deficiency inhibits the myeloperoxidase activity and thus decreases the bacteriocide effect of the leucocytes. In spite of this, when exposed to infections the physiological mechanisms reduce the blood concentration of available iron. By this mode of action, invading pathogens, needing iron like the host animals, will be restrained. The low content of iron in milk (Table II) combined with a high content of iron binding lactoferrin, is ideal to protect newborn and milk fed young animals against intestinal infections.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Iron deficiency in domestic animals]. 643 95

Concentration of malonic dialdehyde (MDA) and activity of antioxidant enzymes G-6-PD, glutation peroxidase (GP), glutation reductase, catalase, superoxide dismutase were measured in red cells of patients with polycythemia vera. Plasmic ions Fe3+ were estimated by means of electron-paramagnetic resonance. MDA concentration and antioxidant enzymes (except GP) in polycythemia red cells were found increased, while the activity of selenium-dependent GP was reduced, the inhibition being greatest in severe iron deficiency. It is suggested that GP activity in red cells depends on both selenium levels in the body and concentrations of non-hematic iron.
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PMID:[Erythremia: the activity of erythrocyte antioxidant enzymes and the association with iron deficiency]. 921 64

The response of both specific (ascorbate peroxidase, APX) and unspecific (POD) peroxidases and H(2)O(2) content of sunflower plants (Helianthus annuus L. cv. Hor) grown hydroponically with (C) or without (-Fe) iron in the nutrient solution were analysed to verify whether iron deficiency led to cell oxidative status. In -Fe leaves a significant increase of H(2)O(2) content was detected, a result confirmed by electron microscopy analysis. As regards extracellular peroxidases, while APX activity significantly decreased, no change was observed in either soluble guaiacol or syringaldazine-dependent POD activity following iron starvation. Moreover, guaiacol-dependent POD activity was found to decrease in both ionically and covalently-cell-wall bound fractions, while syringaldazine-POD activity decreased only in the covalently-bound fraction. At the intracellular level both guaiacol-POD and APX activities underwent a significant decrease. The overall reduction of peroxidase activity was confirmed by the electrophoretic separation of POD isoforms and, at the extracellular level, by cytochemical localization of peroxidases by diaminobenzidine staining. The electrophoretic separation, besides quantitative differences, also revealed quantitative changes, particularly evident for ionically and covalently-bound fractions. Therefore, in sunflower plants, iron deficiency seems to affect the different peroxidase isoenzymes to different extents and to induce a secondary oxidative stress, as indicated by the increased levels of H(2)O(2). However, owing to the almost completely lack of catalytic iron capable of triggering the Fenton reaction, iron-deficient sunflower plants are probably still sufficiently protected against oxidative stress.
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PMID:Iron deficiency differently affects peroxidase isoforms in sunflower. 1118 10


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