Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0004623 (bacterial infection)
 15,226 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

1. Rats suffering from protein-energy malnutrition were found to have low serum iron, low PCV, and low hemoglobin concentrations. 2. Oral iron supplement during the refeeding of these animals caused various types of infection, the severity of which was related to the dose given. 3. A close association between high serum iron, low serum transferrin, and high incidence of bacterial infection was found. 4. A high protein diet without any oral iron supplement was found to raise the PCV and hemoglobin concentration to the same levels as a high protein diet containing 65 mg iron/kg body wt/day, although this dose of iron was sufficient to produce infection in the malnourished rats during refeeding. Speculation Iron supplementation during the treatment of children with protein-energy malnutrition may predispose to bacterial infection, the severity of which depends on the dose of iron given.
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PMID:Iron therapy and refeeding in experimentally malnourished rats. 9 12

As a rule bacterial infection is followed by acute serum iron reduction; impaired inflow of iron from storage sites into the transport pool represents the main cause. As a consequence of this sort of iron redistribution iron becomes short for red cell production; this is one cause for the development of anemia. The biological significance of hyposideremia may be presumed from the bacteriostatic potential of iron free transferrin, preventing adequate iron acquisition by multiplying microorganisms. Preliminary animal experiments support this concept and suggest that it might also be applied to true iron deficiency.
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PMID:[Iron deficiency in infection]. 36 3

The ancients used bloodletting extensively in infectious and other diseases. When recent work on iron and bacterial infection is taken into account, it is possible to argue that bloodletting, which reduced plasma iron and transferrin saturation, might have been of value in increasing resistance to infection by bacteria or plasmodia. Galen's bloodletting methods are summarized, and their probable effect on plasma iron is considered. The ancient physicans who had no specific remedies for infection whatsoever, may well have been justified in making responsible use of bloodletting, both for the treatment and for the prophylaxis of infectious disease.
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PMID:In defence of ancient bloodletting. 38 31

1. The effects of bacterial infection and temperature on serum iron levels were investigated in the lizard Dipsosaurus dorsalis. 2. Changes in body temperature from normal (38 degrees C) to febrile (41 degrees C) did not alter serum iron levels. Injection with Aeromonas hydrophila led to a significant reduction in serum iron levels, comparable to that found in mammals. This reduction in serum iron level was independent of the lizard's body temperature. 3. When grown in vitro, A. hydrophila grew equally well at afebrile (38 degrees C) and febrile (41 degrees C) temperatures. When the iron levels of the growth medium were reduced, the bacterial growth was diminished at the febrile temperature but was not significantly affected at the afebrile temperature. 4. The addition of iron supplements to bacterially infected lizards led to an increase in the percent mortality. 5. These results indicate that one of the mechanisms behind the beneficial, or adaptive value of fever in D. dorsalis is the decrease in iron available to the pathogenic micro-organisms.
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PMID:Fever and survival: the role of serum iron. 67 29

Chicks aged 15 days were infected orally with Salmonella gallinarum. During the six-day period immediately following infection the absorption of 59Fe from the gut fell progressively to be eventually about half that in noninfected chicks. This reduced uptake was accompanied by a shift in the distribution of the 59Fe absorbed, more occurring in the spleen and less in the liver and blood. During the eight-day period that immediately followed infection in another experiment, serum iron concentration on day 4 and 6 in infected chicks was significantly lower than that in noninfected birds. In the infected chicks also the transferrin saturation was significantly lower and the unsaturated ironbinding capacity higher, on days 4, 6, and 8 after infection. These findings show that there is a major disturbance in iron regulation in acute systemic bacterial infection in the immature fowl and suggest that the mild anaemia which occurs in chicks during acute S gallinarum infection a shortage of iron in the body.
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PMID:Altered absorption and regulation of iron in chicks with acute Salmonella gallinarum infection. 87 34

Iron, as participant of many biological processes is a prerequisite for life. Uptake, internal transport and storage by organisms is handled by highly specialized chemical systems endowed with strong metal binding affinities. Apart from the homeostatic function of iron-binding compounds they appear of significance for inter-species interactions. Thus, by tight binding transferrin withholds the iron from invading microorganisms required for their optimal growth. This bacteriostatic property of the iron transport protein is however partially overcome by small molecular substances synthesized by bacteria and successfully competing for the metal. The balance of such interaction is a complex one. Yet, strong evidence points to the crucial importance of the amount of iron offered by a host to infecting agents for determining the fate of bacterial disease.
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PMID:An other look at iron: role in host pathogen interaction. 110

Cerebral malaria is a severe complication of Plasmodium falciparum infection in children, with a mortality rate of 15-50% despite antimalarial therapy. In order to determine whether combining iron chelation with quinine therapy speeds recovery of consciousness, the authors conducted a randomized, double-blind, placebo-controlled trial of the iron chelator deferoxamine in 83 Zambian children with cerebral malaria. To be enrolled, patients had to be under age 6, have P. falciparum parasitemia, have normal cerebrospinal fluid without evidence of bacterial infection, and be in a coma from which they cannot be aroused. Deferoxamine (100 mg/kg of body weight/day, infused intravenously for 72 hours) or placebo was added to standard therapy with quinine and sulfadoxine-pryimethamine. The time to recovery of full consciousness, time to parasite clearance, and mortality were examined with Cox proportional-hazards regression analysis. The rate of recovery of full consciousness among the 42 patients given deferoxamine was 1.3 time that among the 41 who received the placebo (95% confidence interval [CI], 0.7-2.3; the median time to recovery was 20.2 hours in the deferoxamine group, and 43.1 hours in the placebo group (p=0.38). Among 50 patients in deep coma, the rate of recovery of full consciousness was increased 2.2-fold with deferoxamine (95% CI, 1.1-4-7), decreasing the median recovery time from 68.2 to 24.1 hours (p=0.03). Among 69 patients for whom data on parasite clearance were available, the rate of clearance with deferoxamine was 2.0 times that with placebo (95% CI, 1.2-3.6). Among all 83 patients, mortality was 17% in the deferoxamine group and 22% in the placebo group (p=0.52). It is concluded that iron chelation therapy may speed the clearance of parasitemia and enhance recovery from deep coma in cerebral malaria.
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PMID:Effect of iron chelation therapy on recovery from deep coma in children with cerebral malaria. 845 79

Bacterial colonization of the tracheo-bronchial tree is common and an established risk factor for infection in ventilated newborns. Elastase, a highly active proteinase, and lactoferrin, an iron-binding protein and potential modulator of the inflammatory process, are both major constituents of either azurophilic or primary granules of neutrophilic granulocytes, released by activation of these cells during the inflammatory response. Since both elastase, complexed with its major inhibitor alpha 1-proteinase inhibitor (E alpha 1-Pl), and lactoferrin (Lf) are indicators of granulocyte activation during bacterial infection, they may indicate infectious inflammation at the tracheobronchial site. To study whether these substances in a single suction probe may serve this purpose, we obtained 82 tracheo-bronchial aspirates routinely from 16 ventilated newborns with a median gestational age of 31.5 (range, 25-39) weeks for laboratory analysis and bacterial cultures. Systemic inflammatory response by differential white blood cell count and C-reactive protein (CRP) was monitored simultaneously. The median E alpha 1-Pl level was significantly elevated in culture-positive aspirates (1,005 micrograms/L; range, less than 30-29,240 micrograms/L) in contrast to culture-negative samples (158 micrograms/L; range, less than 30-1,408 micrograms/L). In addition to a diagnostic sensitivity of 77%, E alpha 1-Pl offered a high specificity of 88%, a positive predictive value of 97%, and a negative predictive value of 73%. In contrast, median Lf concentration (10.6; range, 0.3-58.3 mg/L vs. 11.7; range, 1.6-158 mg/L) showed no correlation with culture results. Of the culture-positive aspirates 36% corresponded with systemic signs of an acute inflammatory response, such as elevated I/T-ratio and CRP.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Elastase alpha 1-proteinase inhibitor and lactoferrin concentrations in endotracheal aspirates of ventilated newborns. 149 62

Small intestinal cytochromes P450 (P450) provide the principal, initial source of biotransformation of ingested xenobiotics. The consequences of such biotransformation are detoxification by facilitating excretion, or toxification by bioactivation. P450s occur at highest concentrations in the duodenum, near the pylorus, and at decreasing concentrations distally--being lowest in the ileum. Highest concentrations occur from midvillus to villous tip, with little or none occurring in the crypts of Lieberkuehn. Microsomal P4503A, 2C8-10, and 2D6 forms have been identified in human small intestine, and P450s 2B1, possibly 2B2, 2A1, and 3A1/2 were located in endoplasmic reticulum of rodent small intestine, while P4502B4 has been purified to electrophoretic homogeneity from rabbit intestine. Some evidence indicates a differential distribution of P450 forms along the length of the small intestine and even along the villus. Rat intestinal P450s are inducible by xenobiotics--with phenobarbital (PB) inducing P4502B1, 3-methylcholanthrene (3-MC) inducing P4501A1, and dexamethasone inducing two forms of P4503A. Induction is most effectively achieved by oral administration of the agents, and is rapid--aryl hydrocarbon hydroxylase (AHH) was increased within 1 h of administration of, for example, 3-MC. AHH, 7-ethoxycoumarin O-deethylase (ECOD), and 7-ethoxyresorufin O-deethylase (EROD) have been used most frequently as substrates to characterize intestinal P450s. Dietary factors affect intestinal P450s markedly--iron restriction rapidly decreased intestinal P450 to beneath detectable values; selenium deficiency acted similarly but was less effective; Brussels sprouts increased intestinal AHH activity 9.8-fold, ECOD activity 3.2-fold, and P450 1.9-fold; fried meat and dietary fat significantly increased intestinal EROD activity; a vitamin A-deficient diet increased, and a vitamin A-rich diet decreased intestinal P450 activities; and excess cholesterol in the diet increased intestinal P450 activity. The role of intestinal P450 in toxifying or detoxifying specific xenobiotics has been clearly demonstrated to only a limited extent. However, elevated intestinal P450 levels have been indirectly linked to gastrointestinal cancer. Intestinal metabolism of 2,2,2-trifluoroethanol produces intestinal lesions with consequent systemic bacterial infection.
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PMID:Small intestinal cytochromes P450. 180 46

Iron overload increases the risk of bacterial infection in dialysis patients, partly by impairing functions of the polymorphonuclear granulocytes (PMNs). PMN defence was studied sequentially in haemodialysis patients with transfusional haemosiderosis, treated for 6 +/- 1.5 months (n = 8) to 13 +/- 1.7 months (n = 4) with recombinant human erythropoietin (rHuEpo). Over this period, signs of iron overload (increased serum ferritin and serum iron) improved, and stainable iron disappeared in PMNs. Simultaneously, phagocytosis of Yersinia enterocolitica by PMNs improved. The decrease in serum ferritin was significantly related to the improved phagocytosis. Killing of Y. enterocolitica by PMNs also improved. It is anticipated that rHuEpo therapy in iron-overloaded dialysis patients could decrease the incidence of bacterial infection by improving PMN functions in these patients.
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PMID:Recombinant erythropoietin reverses polymorphonuclear granulocyte dysfunction in iron-overloaded dialysis patients. 213 Feb 96


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