PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “HEMOGLOBIN AND COMPOUNDS”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 127 records · Page 7Linked to original sources

N-Oxide reduction by hemoglobin, cytochrome C and ferrous ions.

Indicine N-oxide is reduced to indicine by Fe(II) ions, by enzymatically reduced cytochrome c, and by ascorbic acid in conjunction with hemin or cytochrome c. Indicine N-oxide is not reduced by native hemoglobin, but is reduced by denatured hemoglobin. Oxygen competes with indicine N-oxide for reduction by denatured hemoglobin.

Antineoplastic Agents, Phytogenic↗

Antioxidant action of certain simple phenolic compounds derived from Chinese herbs.

H2O2 and hydroxyl free radical active oxygen generation systems were utilized to define the antioxidant activities of simple phenolic compounds derived from Chinese herbs. Although the antioxidant activities of compounds differed when assessed in the two systems, all compounds tested were found to be effective at preventing red blood cell membrane lipid peroxidation, with the propyl and butyl esters of gallic acid being especially potent. No compound was able to prevent hemoglobin oxidation. All compounds but salicylic acid were found to interact dose-dependently with H2O2 and hydroxyl free radical as determined by a chemiluminescence method.

Antioxidants↗

Effect of dietary iron level on efficiency of converting food iron into hemoglobin by the anemic rat.

The effects of varying the dietary levels of ferrous sulfate or ferric orthophosphate on the efficiency of the conversion of dietary iron into hemoglobin iron, was evaluated with the anemic rat. Weanling male rats were made anemic by feeding a semipurified diet containing 8.4 mg iron/kg, and by bleeding. They were divided into nine groups so that hemoglobin levels and body weights were similar. The rats were fed the basal diet or basal diet plus 12, 24, 36 and 48 mg iron/kg diet provided as ferrous sulfate or ferric orthophosphate. The rats were fed 10 g daily of the respective diets for 10 consecutive days. The efficiency of the conversion of dietary iron into hemoglobin iron was not significantly affected by dietary level of either iron salt. It was determined that ferric orthophosphate was 51% as efficient as ferrous sulfate for hemoglobin regeneration in the anemic rat.

Anemia↗

Bioavailability of carbonyl iron: a randomized, double-blind study.

49 female blood donors with iron-deficiency anemia were treated with equal doses of iron either as carbonyl iron or ferrous sulfate in a randomized, double-blind fashion. The prevalence of side-effects was similar in the two groups. Mean values for hemoglobin concentration, mean corpuscular volume, corrected reticulocyte count, platelet count, serum iron, total iron-binding capacity, transferrin saturation or erythrocyte protoporphyrin did not differ significantly between the two groups throughout the study. After 16 weeks of therapy, the mean increase in hemoglobin iron was similar in both groups (p = 0.2). Estimates of net changes in total body iron suggested that the overall bioavailability of carbonyl iron was high, about 70% that of ferrous sulfate.

Adult↗

Molecular characterization of hemoglobin C in Thailand.

We describe hematologic and DNA characterization of 12 hemoglobin C heterozygotes and three compound heterozygotes for hemoglobin C and hemoglobin E found in Thailand. Amplification and DNA analysis of genomic DNA by the polymerase chain reaction procedure permitted the identification of the beta(C) mutation at codon 6 of beta-globin gene (beta 6; GAG-AAG). beta-Globin gene haplotype analysis demonstrated that all beta(C) globin genes detected in these Thai individuals were associated with the haplotype (+ - - - - - +), indicating a non-African origin of this abnormal hemoglobin in Thailand. On routine hemoglobin typing, hemoglobin C is usually mistakenly identified as hemoglobin E because of theirs similar mobilities on cellulose acetate electrophoresis. The simple DNA assay for hemoglobin C based on an allele-specific polymerase chain reaction for accurate diagnosis of hemoglobin C was therefore developed.

Adult↗

Studies on the linkage between spin equilibria and protein structure in carp ferric hemoglobin.

The effects of protein conformation on the spin-state equilibria of several derivatives of carp hemoglobin have been examined. This has been done by measuring the pH dependence of the paramagnetic susceptibilities of these derivatives in the presence and absence of inositol hexakisphosphate, P6-inositol. In all cases the addition of P6-inositol at low pH and the lowering of the pH in the presence of P6-inositol shift the spin-state equilibrium in favor of the high-spin electronic configuration. The P6-inositol and pH dependence of these magnetic properties parallels the pH and P6-inositol dependence of the conformational state of the hemoglobin as determined in earlier studies and further supports a thermodynamic linkage between the electronic state of the iron atoms and the quaternary structure of the hemoglobin molecule.

Animals↗

The increase of body iron stores estimated by the increase of serum ferritin concentration during ferrous sulphate treatment after gastrointestinal surgery.

A 6-wk period of iron therapy with ferrous sulphate (80 mg Fe++ three times daily) was given to 16 males and 16 females on whom previously various common gastrointestinal surgery had been performed and who had empty iron stores estimated from low serum ferritin concentration. The results were compared with a control group corresponding to the study group in respect to sex, number of patients, primary disease, previous operation, and the empty iron stores. The iron therapy replenished the empty body iron stores, because the serum ferritin concentrations increased from 11 +/- 7 to 35 +/ 13 micrograms/liter (p less than 0.001) in the males and from 9 +/- 6 to 30 +/- 10 micrograms/liter (p less than 0.001) in the females, whereas the corresponding changes in the control group were from 10 +/- 9 to 11 +/- 8 micrograms/liter and from 11 +/- 8 to 13 +/- 11 micrograms/liter in the males and females, respectively. Also the blood hemoglobin concentration increased in the group receiving iron from 136 +/- 11 to 150 +/- 11 g/liter (p less than 0.01) and from 130 +/- 12 to 142 +/- 11 g/liter (p less than 0.01) and the serum iron from 14 +/- 6 to 18 +/- 5 mmol/liter (p less than 0.01) and from 13 +/- 6 to 17 +/- 6 mmol/liter (p less than 0.01) in males and females, respectively, whereas corresponding changes in the control group for hemoglobin were from 135 +/- 10 to 137 +/- 11 g/liter and from 129 +/- 11 to 131 +/- 10 g/liter and for serum iron from 14 +/- 6 to 14 +/- 5 mmol/liter and from 14 +/- 6 to 14 +/- 5 mmol/liter, in the males and females, respectively. The response to iron treatment varied considerably between different patients, because in some few patients serum ferritin decreased during the study and in some the increase was several-fold the initial value. The study shows that ferrous sulphate treatment is an effective and practical way to replenish the empty iron stores, estimated from serum ferritin concentrations, in patients after various gastrointestinal surgery and that concomitantly the blood hemoglobin and serum iron concentrations will increase.

Adult↗

Studies on avian erythrocyte metabolism. VII. Effect of inositol pentaphosphate and other organic phosphates on oxygen affinity of the embryonic and adult-type hemoglobins of the turkey embryo.

The effects of 2, 3-diphosphoglyceric acid (2, 3-DPG), adenosine triphosphate (ATP), inositol tetraphosphate (ITP), inositol pentaphosphate (IPP), and inositol hexaphosphate (IHP) on oxygen affinity of whole stripped hemoglobin (WSH), hemoglobin H (Hb-H; hatching hemoglobin), hemoglobin A (Hb-A), and hemoglobin D (Hb-D) isolated from erythrocytes (RBC) of the 25-day turkey embryo have been studied. The order of the decrease in oxygen affinity induced by these organic phosphates, at molar ratios of phosphate compound to hemoglobin (tetramer) between 2 and 4, is 2, 3-DPG less than ATP less than ITP less than IPP less than IHP. 2, 3-DPG shows a slightly greater effect on reducing oxygen affinity of Hb-H than on either adult-type hemoglobin. The effect of IPP upon lowering the oxygen affinity of either WSH, Hb-H, Hb-A, or Hb-D is approximately 20 percent less than IHP. The effects of the various organic phosphates upon the Hill constant, n, of these purified hemoglobins is variable but appears to reach a maximum when the molar ratio of organic phosphate to hemoglobin (tetramer) is 2 or greater. None of the physiologically occurring organic phosphates has a significant preferential interaction with any specific hemoglobin. These experiments strengthen and support our earlier conclusion, that the changes in whole blood oxygen affinity which occur during avian development result from the changes in composition of the intraerythrocytic organic phosphates.

Adenosine Diphosphate↗

Functional and spectroscopic evidence for a conformational transition in ferrous liganded human hemoglobin.

The effect of pH and/or organic phosphate on the kinetics of O2 dissociation from oxygenated human hemoglobin and on the spectroscopic features shown by the ferrous nitrosylated derivative of human hemoglobin has been investigated. The results indicate the occurrence of conformational change(s) taking place in liganded ferrous hemoglobin, bringing about a faster kinetic ligand dissociation process, accompanied by the appearance of peculiar spectroscopic features of the ferrous nitrosylated hemoglobin. Altogether these functional and spectroscopic observations indicate the existence of a nesting of tertiary and/or quaternary conformations in the liganded forms of human hemoglobin which may account for the action of heterotropic effectors, such as protons and organic phosphates.

Ferrous Compounds↗

Hemoglobin effects in the Saville assay.

There is a great need to establish accurate, sensitive methods for measuring the concentration of nitrosothiols. Although some progress may have been made recently, differing methodologies have lead to reports of basal levels of nitrosothiols in human plasma that differ by three orders of magnitude. The Saville assay has been widely accepted as an accurate method for measuring nitrosothiols, but one that suffers from sensitivity below that of some other methods. Recently, it has been suggested that when hemoglobin is included in reaction mixtures used for the Saville assay, the sensitivity can be increased by an order of magnitude. Here we show that, on the contrary, the presence of sufficient hemoglobin in the Saville assay decreases its sensitivity.

Azo Compounds↗

Blocking action of parenteral desferrioxamine on iron absorption in rodents and men.

Desferrioxamine (DFO) is an iron chelating agent that, when administered orally, interferes with gut absorption of inorganic iron and, when administered parenterally, binds body iron and is excreted as ferrioxamine in bile and urine. Studies were carried out in normal and iron-deficient male rats and in normal, iron-replete male volunteers to investigate the blocking action of parenteral DFO on the absorption of radioiron. Radiolabeled ferrous ammonium sulfate, transferrin iron, or hemoglobin iron was injected directly into the jejunum of rats with or without intramuscular injections of DFO. Radioiron administered as ferrous sulfate or as transferrin iron was given to the volunteers by mouth or by direct duodenal infusion, respectively, with or without intravenous infusions of DFO. In iron-deficient rats, intramuscular DFO injections commencing 1 h before direct jejunal injection of radioiron significantly blocked absorption of inorganic iron (26% with DFO, 64% without DFO), transferrin iron (4% with DFO, 69% without DFO), and hemoglobin iron (3% with DFO, 19% without DFO). In normal rats, DFO injections also significantly blocked absorption of inorganic iron and transferrin iron. In normal volunteers, intravenous DFO infusions commencing 1 h before administration of radioiron significantly blocked absorption of physiologic doses of inorganic iron (3% with DFO, 21% without DFO) and transferrin iron (1% with DFO, 20% without DFO). The quantity of radioiron excreted in urine by both rats and humans with administration of DFO did not account for the observed decrement in absorption of radioiron. Biochemical analysis of rat intestinal mucosal scrapings after injection of DFO and administration of radioiron demonstrated the accumulation of a small molecular weight fraction containing iron that was ferrioxamine (iron-chelate) complex. We conclude that parenterally administered DFO can enter the small intestinal mucosa, bind intracellular iron, and block iron absorption. Parenteral DFO blocks the absorption of inorganic iron, transferrin iron, and hemoglobin iron, suggesting that all three iron species enter a common chelatable pool within the small intestinal mucosa and may share a common pathway of absorption.

Adult↗

Improvement in iron deficiency anemia through therapy with ferric ammonium citrate and vitamin C and the effects of aerobic exercise.

In 781 female college students, there were 41 cases of iron deficiency anemia, 209 of latent iron deficiency, 3 of other anemias, and 528 normal cases. Fifty-four volunteers recruited from the iron deficiency anemia and severe latent iron deficiency groups were randomly divided into 4 study groups. Groups I and III received 500 mg of vitamin C daily, and groups II and IV received ferric ammonium citrate (FeAC; equivalent to 6 mg iron) in addition to vitamin C for 9 weeks. Groups I and II were loaded by aerobic exercise at 50% VO2 max. Significant differences between groups were noted in serum ferritin (SF) in III/IV, hematocrit (Ht) in II/III and III/IV, and reticulocytes (RET) in I/II, I/IV, and III/IV. Hemoglobin (Hb) and other iron-related blood indices tended to normalize in groups II and IV when compared with the pre-values. VO2 max was elevated in groups I and II regardless of iron treatment, but was augmented more in group II than group I.

Adolescent↗

Intrinsic activity at the molecular level: E. J. Ariëns' concept visualized.

The concept of using affinity and intrinsic activity to analyze drug interactions with receptors has had a long history in pharmacological studies. In the simplest case, the biological response will be proportional to the amount of drug bound, i.e. its affinity. However, the biological response is also mediated by the ability of a drug when bound to exert its maximum effectiveness. This effectiveness is termed the intrinsic activity. Physicochemical processes have been thought to be at the basis of intrinsic activity. Detailed oxygen and solution binding experiments combined with X-ray crystallographic studies on allosteric effectors to hemoglobin demonstrate that these potential drug agents bind at the same site in hemoglobin with similar binding constants yet shift the allosteric equilibrium and the oxygen affinity of the T-structure by different degrees. Therefore some of the effectors with similar binding affinities for the same site exhibit varying degrees of affectiveness, i.e. they possess different intrinsic activities. The intrinsic activity of the effector is defined as the ratio of the oxygen affinity constant to the T-state with drug/oxygen affinity constant to the T-state without drug (KT+drug)/(KT control). The source of the intrinsic activity appears to be the ability of the effectors to interact with key residues such as Lys99 alpha at the binding site. These results suggest a general molecular mechanism for allosteric effector modulation of hemoglobin function that might be of use in other allosteric enzyme systems.

Allosteric Regulation↗