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Sample records for hemoglobin

  1. Hemoglobin (image)

    MedlinePlus

    Hemoglobin is the most important component of red blood cells. It is composed of a protein called ... exchanged for carbon dioxide. Abnormalities of an individual's hemoglobin value can indicate defects in the normal balance ...

  2. Hemoglobin substitutes.

    PubMed

    Anbari, Kevin K; Garino, Jonathan P; Mackenzie, Colin F

    2004-10-01

    Orthopaedic patients frequently require blood transfusions to treat peri-operative anemia. Research in the area of hemoglobin substitutes has been of great interest since it holds the promise of reducing the reliance on allogeneic blood transfusions. The three categories of hemoglobin substitutes are (1) cell-free, extracellular hemoglobin preparations made from human or bovine hemoglobin (hemoglobin-based oxygen carriers or HBOCs); (2) fluorine-substituted linear or cyclic carbon chains with a high oxygen-carrying capacity (perfluorocarbons); and (3) liposome-encapsulated hemoglobin. Of the three, HBOCs have been the most extensively studied and tested in preclinical and clinical trials that have shown success in diminishing the number of blood transfusions as well as an overall favorable side-effect profile. This has been demonstrated in vascular, cardiothoracic, and orthopaedic patients. HBOC-201, which is a preparation of cell-free bovine hemoglobin, has been approved for clinical use in South Africa. These products may well become an important tool for physicians treating peri-operative anemia in orthopaedic patients.

  3. Hemoglobin electrophoresis

    MedlinePlus

    ... sickle cell anemia. Other, less common, abnormal Hb molecules cause other types of anemia . ... adults, these are normal percentages of different hemoglobin molecules: Hb A: 95% to 98% Hb A2: 2% ...

  4. Hemoglobin derivatives

    MedlinePlus

    ... in red blood cells that moves oxygen and carbon dioxide between the lungs and body tissues. This article ... attached to carbon monoxide instead of oxygen or carbon dioxide. High amounts of this type of abnormal hemoglobin ...

  5. Serum free hemoglobin test

    MedlinePlus

    Blood hemoglobin; Serum hemoglobin ... Hemoglobin (Hb) is the main component of red blood cells. It is a protein that carries oxygen. ... people may contain up to 5 mg/dL hemoglobin. Normal value ranges may vary slightly among different ...

  6. Hemoglobin C disease

    MedlinePlus

    Clinical hemoglobin C ... Hemoglobin C is an abnormal type of hemoglobin, the protein in red blood cells that carries oxygen. It is ... Americans. You are more likely to have hemoglobin C disease if someone in your family has had ...

  7. The Hemoglobin E Thalassemias

    PubMed Central

    Fucharoen, Suthat; Weatherall, David J.

    2012-01-01

    Hemoglobin E (HbE) is an extremely common structural hemoglobin variant that occurs at high frequencies throughout many Asian countries. It is a β-hemoglobin variant, which is produced at a slightly reduced rate and hence has the phenotype of a mild form of β thalassemia. Its interactions with different forms of α thalassemia result in a wide variety of clinical disorders, whereas its coinheritance with β thalassemia, a condition called hemoglobin E β thalassemia, is by far the most common severe form of β thalassemia in Asia and, globally, comprises approximately 50% of the clinically severe β-thalassemia disorders. PMID:22908199

  8. Phylogeny of Echinoderm Hemoglobins

    PubMed Central

    Christensen, Ana B.; Herman, Joseph L.; Elphick, Maurice R.; Kober, Kord M.; Janies, Daniel; Linchangco, Gregorio; Semmens, Dean C.; Bailly, Xavier; Vinogradov, Serge N.; Hoogewijs, David

    2015-01-01

    Background Recent genomic information has revealed that neuroglobin and cytoglobin are the two principal lineages of vertebrate hemoglobins, with the latter encompassing the familiar myoglobin and α-globin/β-globin tetramer hemoglobin, and several minor groups. In contrast, very little is known about hemoglobins in echinoderms, a phylum of exclusively marine organisms closely related to vertebrates, beyond the presence of coelomic hemoglobins in sea cucumbers and brittle stars. We identified about 50 hemoglobins in sea urchin, starfish and sea cucumber genomes and transcriptomes, and used Bayesian inference to carry out a molecular phylogenetic analysis of their relationship to vertebrate sequences, specifically, to assess the hypothesis that the neuroglobin and cytoglobin lineages are also present in echinoderms. Results The genome of the sea urchin Strongylocentrotus purpuratus encodes several hemoglobins, including a unique chimeric 14-domain globin, 2 androglobin isoforms and a unique single androglobin domain protein. Other strongylocentrotid genomes appear to have similar repertoires of globin genes. We carried out molecular phylogenetic analyses of 52 hemoglobins identified in sea urchin, brittle star and sea cucumber genomes and transcriptomes, using different multiple sequence alignment methods coupled with Bayesian and maximum likelihood approaches. The results demonstrate that there are two major globin lineages in echinoderms, which are related to the vertebrate neuroglobin and cytoglobin lineages. Furthermore, the brittle star and sea cucumber coelomic hemoglobins appear to have evolved independently from the cytoglobin lineage, similar to the evolution of erythroid oxygen binding globins in cyclostomes and vertebrates. Conclusion The presence of echinoderm globins related to the vertebrate neuroglobin and cytoglobin lineages suggests that the split between neuroglobins and cytoglobins occurred in the deuterostome ancestor shared by echinoderms and

  9. THE RENAL HANDLING OF HEMOGLOBIN

    PubMed Central

    Bunn, H. Franklin; Esham, William T.; Bull, Robert W.

    1969-01-01

    The glomerular filtration of hemoglobin (α2β2) was studied under conditions in which its dissociation into αβ dimers was experimentally altered. Rats receiving hemoglobin treated with the sulfhydryl reagent bis(N-maleimidomethyl) ether (BME) showed a much lower renal excretion and prolonged plasma survival as compared with animals injected with untreated hemoglobin. Plasma disappearance was also prolonged in dogs receiving BME hemoglobin. Gel filtration data indicated that under physiological conditions, BME hemoglobin had impaired subunit dissociation. In addition, BME hemoglobin showed a very high oxygen affinity and a decreased rate of auto-oxidation. Glomerular filtration was enhanced under conditions which favor the dissociation of hemoglobin into dimers. Cat hemoglobin, which forms subunits much more extensively than canine hemoglobin, was excreted more readily by the rat kidney. The renal uptake of 59Fe hemoglobin injected intra-arterially into rabbits varied inversely with the concentration of the injected dose. PMID:5778789

  10. Rice (Oryza) hemoglobins

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hemoglobins (Hbs) corresponding to non-symbiotic (nsHb) and truncated (tHb) Hbs have been identified in rice (Oryza). This review discusses the major findings from the current studies on rice Hbs. At the molecular level, a family of the nshb genes, consisting of hb1, hb2, hb3, hb4 and hb5, and a sin...

  11. Temperature modulation of bovine hemoglobins.

    PubMed

    Condò, S G; el-Sherbini, S; Giardina, B

    1991-06-28

    The functional properties of hemoglobin from Egyptian water buffalo have been characterized as a function of pH, temperature and chloride concentration. Alongside overall similarities shared with ox and Arctic ruminant hemoglobins, hemoglobin from buffalo shows significant differences with respect to the effect of temperature. The results obtained may suggest that the limited effect of temperature on oxygen binding recently reported for ox hemoglobin could be regarded as an interesting case of a reminiscence of a past glacial age.

  12. Hemoglobin interacting proteins and implications of spectrin hemoglobin interaction.

    PubMed

    Basu, Avik; Chakrabarti, Abhijit

    2015-10-14

    In this report we have analyzed interacting partners of hemoglobin inside erythrocyte and sought possible implications of hemoglobin-spectrin interaction. Our list of identified cytosolic hemoglobin interacting proteins includes redox regulators like peroxiredoxin-2, Cu-Zn superoxide dismutase, catalase, aldehyde dehydrogenase-1, flavin reductase and chaperones like HSP70, α-hemoglobin stabilizing protein. Others include metabolic enzymes like carbonic anhydrase-1, selenium binding protein-1, purine nucleoside phosphorylase and nucleoside diphosphate kinase. Additionally, various membrane proteins like α and β spectrin, ankyrin, band3, protein4.1, actin and glyceraldehyde 3 phosphate dehydrogenase have been shown to interact with hemoglobin. Our result indicates that major membrane skeleton protein spectrin, that also has a chaperone like activity, helps to fold the unstable alpha-globin chains in vitro. Taken together our results could provide insight into a protein network evolved around hemoglobin molecule inside erythrocyte that may add a new perspective in understanding the hemoglobin function and homeostasis.

  13. Antimicrobial properties of hemoglobin.

    PubMed

    Sheshadri, Preethi; Abraham, Jayanthi

    2012-12-01

    Hemoglobin consists of a heme containing component and a globin unit. It exists as a tetramer with 2 α subunits and 2 β subunits in adults and with 2 α subunits and 2 γ chains in infants. On proteolytic cleavage, hemoglobin breaks down to produce many biologically active compounds, among which are hemocidins, those which exhibit antimicrobial property. The generation of these peptides does not depend on the blood group, Rhesus factor, age and sex of the healthy donors. The microbicidal activity has been observed against a variety of gram positive and Gram-negative bacteria, and against filamentous fungi, yeast and even certain parasites. The discovery of hemocidins opens a new field for research into the details of the peptides acting as second line of defence in boosting the innate immune system of the organisms.

  14. Disorders of Human Hemoglobin

    NASA Astrophysics Data System (ADS)

    Bank, Arthur; Mears, J. Gregory; Ramirez, Francesco

    1980-02-01

    Studies of the human hemoglobin system have provided new insights into the regulation of expression of a group of linked human genes, the γ -δ -β globin gene complex in man. In particular, the thalassemia syndromes and related disorders of man are inherited anemias that provide mutations for the study of the regulation of globin gene expression. New methods, including restriction enzyme analysis and cloning of cellular DNA, have made it feasible to define more precisely the structure and organization of the globin genes in cellular DNA. Deletions of specific globin gene fragments have already been found in certain of these disorders and have been applied in prenatal diagnosis.

  15. Subunit dissociation in fish hemoglobins.

    PubMed

    Edelstein, S J; McEwen, B; Gibson, Q H

    1976-12-10

    The tetramer-dimer dissociation equilibria (K 4,2) of several fish hemoglobins have been examined by sedimentation velocity measurements with a scanner-computer system for the ultracentrifuge and by flash photolysis measurements using rapid kinetic methods. Samples studied in detail included hemoglobins from a marine teleost, Brevoortia tyrannus (common name, menhaden); a fresh water teleost, Cyprinus carpio, (common name, carp); and an elasmobranch Prionace glauca (common name, blue shark). For all three species in the CO form at pH 7, in 0.1 M phosphate buffer, sedimentation coefficients of 4.3 S (typical of tetrameric hemoglobin) are observed in the micromolar concentration range. In contrast, mammalian hemoglobins dissociate appreciably to dimers under these conditions. The inability to detect dissociation in three fish hemoglobins at the lowest concentrations examined indicates that K 4,2 must have a value of 10(-8) M or less. In flash photolysis experiments on very dilute solutions in long path length cells, two kinetic components were detected with their proportions varying as expected for an equilibrium between tetramers (the slower component) and dimers (the faster component); values of K 4,2 for the three fish hemoglobins in the range 10(-9) to 10(-8) M were calculated from these data. Thus, the values of K 4,2 for liganded forms of the fish hemoglobins appear to be midway between the value for liganded human hemoglobin (K 4,2 approximately 10(-6) M) and unliganded human hemoglobin (K 4,2 approximately 10(-12) M). This conclusion is supported by measurements on solutions containing guanidine hydrochloride to enhance the degree of dissociation. All three fish hemoglobins are appreciably dissociated at guanidine concentrations of about 0.8 M, which is roughly midway between the guanidine concentrations needed to cause comparable dissociation of liganded human hemoglobin (about 0.4 M) and unliganded human hemoglobin (about 1.6 M). Kinetic measurements on

  16. Hemoglobin variants in Cyprus.

    PubMed

    Kyrri, Andreani R; Felekis, Xenia; Kalogerou, Eleni; Wild, Barbara J; Kythreotis, Loukas; Phylactides, Marios; Kleanthous, Marina

    2009-01-01

    Cyprus, located at the eastern end of the Mediterranean region, has been a place of eastern and western civilizations, and the presence of various hemoglobin (Hb) variants can be considered a testimony to past colonizations of the island. In this study, we report the structural Hb variants identified in the Cypriot population (Greek Cypriots, Maronites, Armenians, and Latinos) during the thalassemia screening of 248,000 subjects carried out at the Thalassaemia Centre, Nicosia, Cyprus, over a period of 26 years. A sample population of 65,668 people was used to determine the frequency and localization of several of the variants identified in Cyprus. The localization of some of the variants in regions where the presence of foreign people was most prevalent provides important clues to the origin of the variants. Twelve structural variants have been identified by DNA sequencing, nine concerning the beta-globin gene and three concerning the alpha-globin gene. The most common beta-globin variants identified were Hb S (0.2%), Hb D-Punjab (0.02%), and Hb Lepore-Washington-Boston (Hb Lepore-WB) (0.03%); the most common alpha-globin variant was Hb Setif (0.1%). The presence of some of these variants is likely to be directly linked to the history of Cyprus, as archeological monuments have been found throughout the island which signify the presence for many years of the Greeks, Syrians, Persians, Arabs, Byzantines, Franks, Venetians, and Turks. PMID:19373583

  17. Oxygen transport by hemoglobin.

    PubMed

    Mairbäurl, Heimo; Weber, Roy E

    2012-04-01

    Hemoglobin (Hb) constitutes a vital link between ambient O2 availability and aerobic metabolism by transporting oxygen (O2) from the respiratory surfaces of the lungs or gills to the O2-consuming tissues. The amount of O2 available to tissues depends on the blood-perfusion rate, as well as the arterio-venous difference in blood O2 contents, which is determined by the respective loading and unloading O2 tensions and Hb-O2-affinity. Short-term adjustments in tissue oxygen delivery in response to decreased O2 supply or increased O2 demand (under exercise, hypoxia at high altitude, cardiovascular disease, and ischemia) are mediated by metabolically induced changes in the red cell levels of allosteric effectors such as protons (H(+)), carbon dioxide (CO2), organic phosphates, and chloride (Cl(-)) that modulate Hb-O2 affinity. The long-term, genetically coded adaptations in oxygen transport encountered in animals that permanently are subjected to low environmental O2 tensions commonly result from changes in the molecular structure of Hb, notably amino acid exchanges that alter Hb's intrinsic O2 affinity or its sensitivity to allosteric effectors. Structure-function studies of animal Hbs and human Hb mutants illustrate the different strategies for adjusting Hb-O2 affinity and optimizing tissue oxygen supply.

  18. Nonlinear photoacoustic spectroscopy of hemoglobin

    SciTech Connect

    Danielli, Amos; Maslov, Konstantin; Favazza, Christopher P.; Xia, Jun; Wang, Lihong V.

    2015-05-18

    As light intensity increases in photoacoustic imaging, the saturation of optical absorption and the temperature dependence of the thermal expansion coefficient result in a measurable nonlinear dependence of the photoacoustic (PA) signal on the excitation pulse fluence. Here, under controlled conditions, we investigate the intensity-dependent photoacoustic signals from oxygenated and deoxygenated hemoglobin at varied optical wavelengths and molecular concentrations. The wavelength and concentration dependencies of the nonlinear PA spectrum are found to be significantly greater in oxygenated hemoglobin than in deoxygenated hemoglobin. These effects are further influenced by the hemoglobin concentration. These nonlinear phenomena provide insights into applications of photoacoustics, such as measurements of average inter-molecular distances on a nm scale or with a tuned selection of wavelengths, a more accurate quantitative PA tomography.

  19. More Refined Experiments with Hemoglobin.

    ERIC Educational Resources Information Center

    Morin, Phillippe

    1985-01-01

    Discusses materials needed, procedures used, and typical results obtained for experiments designed to make a numerical stepwise study of the oxygenation of hemoglobin, myoglobin, and other oxygen carriers. (JN)

  20. Rice ( Oryza) hemoglobins

    PubMed Central

    Arredondo-Peter, Raúl; Moran, Jose F.; Sarath, Gautam

    2014-01-01

    Hemoglobins (Hbs) corresponding to non-symbiotic (nsHb) and truncated (tHb) Hbs have been identified in rice ( Oryza). This review discusses the major findings from the current studies on rice Hbs. At the molecular level, a family of the nshb genes, consisting of hb1, hb2, hb3, hb4 and hb5, and a single copy of the thb gene exist in Oryza sativa var. indica and O. sativa var. japonica, Hb transcripts coexist in rice organs and Hb polypeptides exist in rice embryonic and vegetative organs and in the cytoplasm of differentiating cells. At the structural level, the crystal structure of rice Hb1 has been elucidated, and the structures of the other rice Hbs have been modeled. Kinetic analysis indicated that rice Hb1 and 2, and possibly rice Hb3 and 4, exhibit a very high affinity for O 2, whereas rice Hb5 and tHb possibly exhibit a low to moderate affinity for O 2. Based on the accumulated information on the properties of rice Hbs and data from the analysis of other plant and non-plant Hbs, it is likely that Hbs play a variety of roles in rice organs, including O 2-transport, O 2-sensing, NO-scavenging and redox-signaling. From an evolutionary perspective, an outline for the evolution of rice Hbs is available. Rice nshb and thb genes vertically evolved through different lineages, rice nsHbs evolved into clade I and clade II lineages and rice nshbs and thbs evolved under the effect of neutral selection. This review also reveals lacunae in our ability to completely understand rice Hbs. Primary lacunae are the absence of experimental information about the precise functions of rice Hbs, the properties of modeled rice Hbs and the cis-elements and trans-acting factors that regulate the expression of rice hb genes, and the partial understanding of the evolution of rice Hbs. PMID:25653837

  1. Rice ( Oryza) hemoglobins.

    PubMed

    Arredondo-Peter, Raúl; Moran, Jose F; Sarath, Gautam

    2014-01-01

    Hemoglobins (Hbs) corresponding to non-symbiotic (nsHb) and truncated (tHb) Hbs have been identified in rice ( Oryza). This review discusses the major findings from the current studies on rice Hbs. At the molecular level, a family of the nshb genes, consisting of hb1, hb2, hb3, hb4 and hb5, and a single copy of the thb gene exist in Oryza sativa var. indica and O. sativa var. japonica, Hb transcripts coexist in rice organs and Hb polypeptides exist in rice embryonic and vegetative organs and in the cytoplasm of differentiating cells. At the structural level, the crystal structure of rice Hb1 has been elucidated, and the structures of the other rice Hbs have been modeled. Kinetic analysis indicated that rice Hb1 and 2, and possibly rice Hb3 and 4, exhibit a very high affinity for O 2, whereas rice Hb5 and tHb possibly exhibit a low to moderate affinity for O 2. Based on the accumulated information on the properties of rice Hbs and data from the analysis of other plant and non-plant Hbs, it is likely that Hbs play a variety of roles in rice organs, including O 2-transport, O 2-sensing, NO-scavenging and redox-signaling. From an evolutionary perspective, an outline for the evolution of rice Hbs is available. Rice nshb and thb genes vertically evolved through different lineages, rice nsHbs evolved into clade I and clade II lineages and rice nshbs and thbs evolved under the effect of neutral selection. This review also reveals lacunae in our ability to completely understand rice Hbs. Primary lacunae are the absence of experimental information about the precise functions of rice Hbs, the properties of modeled rice Hbs and the cis-elements and trans-acting factors that regulate the expression of rice hb genes, and the partial understanding of the evolution of rice Hbs.

  2. Reactions of arsine with hemoglobin

    SciTech Connect

    Hatlelid, K.M.; Brailsford, C.; Carter, D.E.

    1996-02-09

    The mechanism of arsine (AsH{sub 3}) induced hemolysis was studied in vitro using isolated red blood cells (RBCs) from the rat or dog. AsH{sub 3}-induced hemolysis of dog red blood cells was completely blocked by carbon monoxide (CO) preincubation and was reduced by pure oxygen (O{sub 2}) compared to incubations in air. Since CO and O{sub 2} bind to heme and also reduced hemolysis, these results suggested a reaction between AsH{sub 3} and hemoglobin in the hemeligand binding pocket or with the heme iron. Further, sodium nitrite induction of methemoglobin (metHb) to 85% and 34% of total Hb in otherwise intact RBCs resulted in 56% and 16% decreases in hemolysis, respectively, after incubation for 4 h. This provided additional evidence for the involvement of hemoglobin in the AsH{sub 3}-induced hemolysis mechanism. Reactions between AsH{sub 3} and hemoglobin were studied in solutions of purified dog hemoglobin. Spectrophotometric studies of the reaction of AsH{sub 3} with various purified hemoglobin species revealed that AsH{sub 3} reacted with HbO{sub 2} to produce metHb and, eventually, degraded Hb characterized by gross precipitation of the protein. AsH{sub 3} did not alter the spectrum of deoxyHb and did not cause degradation of metHb in oxygen, but bound to and reduced metHb in the absence of oxygen. These data indicate that a reaction of AsH{sub 3} with oxygenated hemoglobin, HbO{sub 2}, may lead to hemolysis, but there are reactions between AsH{sub 3} and metHb that may not be directly involved in the hemolytic process. 17 refs., 6 figs.

  3. [Homozygous hemoglobin-E (Hb-EE) disease].

    PubMed

    Amendola, G; Danise, P; Di Palma, A; Franzese, M; Avino, D; D'Arco, A M

    2004-01-01

    The Authors report on a 16 year-old girl, of Cambodian descent, who was admitted to the hospital for hematuria. She showed a mild microcytic, hypochromic anemia with a normal iron balance; clinical examination was normal with neither pallor nor icterus nor splenomegaly; electrophoresis of hemoglobin yielded no hemoglobin A, a sligtly increased amount of HbF and a single band with a mobility similar to that of HbA2; the patient showed no evidence of overt increased hemolysis. With the DNA technology a final diagnosis of homozygous hemoglobin E was made. Hemoglobin E is the most common Hb variant among Southeast Asian populations. The Authors discuss on the benign nature of Hb-EE disease, pointing out that the presence of a single HbE gene in combination with that for beta-thalassemia leads generally to a disorder often comparable in severity to that of homozygous beta-thalassemia. With the recent migration of a high number of people from the countries, where HbE is extremely frequent, to the Western world (including Italy), this thalassemia syndrome is now a global health problem; therefore its knowledge is an important diagnostic challenge to all the experts involved in the care of thalassemic patients.

  4. THE PREPARATION OF COMPLETELY COAGULATED HEMOGLOBIN

    PubMed Central

    Anson, M. L.; Mirsky, A. E.

    1929-01-01

    As a preliminary to the study of the reversal of the coagulation of hemoglobin several methods are described for the preparation of completely denatured and coagulated hemoglobin and the evidence is given that hemoglobin is a typical coagulable protein. PMID:19872511

  5. Hemoglobin

    MedlinePlus

    ... the anemia is severe Some conditions affect RBC production in the bone marrow and may cause an ... there is a problem with red blood cell production and/or lifespan, but it cannot determine the ...

  6. Hemoglobin

    MedlinePlus

    ... disease ) Failure of the right side of the heart ( cor pulmonale ) Severe chronic obstructive pulmonary disease (COPD) Scarring or thickening of the lungs ( pulmonary fibrosis ) and other severe lung disorders Other reasons for ...

  7. Hemoglobin variant (hemoglobin Aalborg) mimicking interstitial pulmonary disease.

    PubMed

    Panou, Vasiliki; Jensen, Peter-Diedrich Mathias; Pedersen, Jan Freddy; Thomsen, Lars Pilegaard; Weinreich, Ulla Møller

    2014-01-01

    Hemoglobin Aalborg is a moderately unstable hemoglobin variant with no affiliation to serious hematological abnormality or major clinical symptoms under normal circumstances. Our index person was a healthy woman of 58, not previously diagnosed with hemoglobinopathy Aalborg, who developed acute respiratory failure after a routine cholecystectomy. Initially she was suspected of idiopathic interstitial lung disease, yet a series of tests uncovered various abnormal physiological parameters and set the diagnosis of hemoglobinopathy Aalborg. This led us to examine a group of the index person's relatives known with hemoglobinopathy Aalborg in order to study whether the same physiological abnormalities would be reencountered. They were all subjected to spirometry and body plethysmography, six-minute walking test, pulse oximetry, and arterial blood gas samples before and after the walking test. The entire study population presented the same physiological anomalies: reduction in diffusion capacity, and abnormalities in P(a)O2 and p50 values; the latter could not be presented by the arterial blood gas analyzer; furthermore there was concordance between pulse oximetry and arterial blood gas samples regarding saturation. These data suggest that, based upon the above mentioned anomalies in physiological parameters, the diagnosis of hemoglobinopathy Aalborg should be considered.

  8. Hemoglobin Variant (Hemoglobin Aalborg) Mimicking Interstitial Pulmonary Disease

    PubMed Central

    Panou, Vasiliki; Jensen, Peter-Diedrich Mathias; Pedersen, Jan Freddy; Thomsen, Lars Pilegaard; Weinreich, Ulla Møller

    2014-01-01

    Hemoglobin Aalborg is a moderately unstable hemoglobin variant with no affiliation to serious hematological abnormality or major clinical symptoms under normal circumstances. Our index person was a healthy woman of 58, not previously diagnosed with hemoglobinopathy Aalborg, who developed acute respiratory failure after a routine cholecystectomy. Initially she was suspected of idiopathic interstitial lung disease, yet a series of tests uncovered various abnormal physiological parameters and set the diagnosis of hemoglobinopathy Aalborg. This led us to examine a group of the index person's relatives known with hemoglobinopathy Aalborg in order to study whether the same physiological abnormalities would be reencountered. They were all subjected to spirometry and body plethysmography, six-minute walking test, pulse oximetry, and arterial blood gas samples before and after the walking test. The entire study population presented the same physiological anomalies: reduction in diffusion capacity, and abnormalities in PaO2 and p50 values; the latter could not be presented by the arterial blood gas analyzer; furthermore there was concordance between pulse oximetry and arterial blood gas samples regarding saturation. These data suggest that, based upon the above mentioned anomalies in physiological parameters, the diagnosis of hemoglobinopathy Aalborg should be considered. PMID:25400945

  9. Determination Of Ph Including Hemoglobin Correction

    DOEpatents

    Maynard, John D.; Hendee, Shonn P.; Rohrscheib, Mark R.; Nunez, David; Alam, M. Kathleen; Franke, James E.; Kemeny, Gabor J.

    2005-09-13

    Methods and apparatuses of determining the pH of a sample. A method can comprise determining an infrared spectrum of the sample, and determining the hemoglobin concentration of the sample. The hemoglobin concentration and the infrared spectrum can then be used to determine the pH of the sample. In some embodiments, the hemoglobin concentration can be used to select an model relating infrared spectra to pH that is applicable at the determined hemoglobin concentration. In other embodiments, a model relating hemoglobin concentration and infrared spectra to pH can be used. An apparatus according to the present invention can comprise an illumination system, adapted to supply radiation to a sample; a collection system, adapted to collect radiation expressed from the sample responsive to the incident radiation; and an analysis system, adapted to relate information about the incident radiation, the expressed radiation, and the hemoglobin concentration of the sample to pH.

  10. Hemoglobin Variants: Biochemical Properties and Clinical Correlates

    PubMed Central

    Thom, Christopher S.; Dickson, Claire F.; Gell, David A.; Weiss, Mitchell J.

    2013-01-01

    Diseases affecting hemoglobin synthesis and function are extremely common worldwide. More than 1000 naturally occurring human hemoglobin variants with single amino acid substitutions throughout the molecule have been discovered, mainly through their clinical and/or laboratory manifestations. These variants alter hemoglobin structure and biochemical properties with physiological effects ranging from insignificant to severe. Studies of these mutations in patients and in the laboratory have produced a wealth of information on hemoglobin biochemistry and biology with significant implications for hematology practice. More generally, landmark studies of hemoglobin performed over the past 60 years have established important paradigms for the disciplines of structural biology, genetics, biochemistry, and medicine. Here we review the major classes of hemoglobin variants, emphasizing general concepts and illustrative examples. PMID:23388674

  11. Hemoglobin variants: biochemical properties and clinical correlates.

    PubMed

    Thom, Christopher S; Dickson, Claire F; Gell, David A; Weiss, Mitchell J

    2013-03-01

    Diseases affecting hemoglobin synthesis and function are extremely common worldwide. More than 1000 naturally occurring human hemoglobin variants with single amino acid substitutions throughout the molecule have been discovered, mainly through their clinical and/or laboratory manifestations. These variants alter hemoglobin structure and biochemical properties with physiological effects ranging from insignificant to severe. Studies of these mutations in patients and in the laboratory have produced a wealth of information on hemoglobin biochemistry and biology with significant implications for hematology practice. More generally, landmark studies of hemoglobin performed over the past 60 years have established important paradigms for the disciplines of structural biology, genetics, biochemistry, and medicine. Here we review the major classes of hemoglobin variants, emphasizing general concepts and illustrative examples.

  12. Hemoglobin Labeled by Radioactive Lysine

    DOE R&D Accomplishments Database

    Bale, W. F.; Yuile, C. L.; DeLaVergne, L.; Miller, L. L.; Whipple, G. H.

    1949-12-08

    This paper reports on the utilization of tagged epsilon carbon of DL-lysine by a dog both anemic and hypoproteinemic due to repeated bleeding plus a diet low in protein. The experiment extended over period of 234 days, a time sufficient to indicate an erythrocyte life span of at least 115 days based upon the rate of replacement of labeled red cell proteins. The proteins of broken down red cells seem not to be used with any great preference for the synthesis of new hemoglobin.

  13. Hemoglobin potentiates central nervous system damage.

    PubMed Central

    Sadrzadeh, S M; Anderson, D K; Panter, S S; Hallaway, P E; Eaton, J W

    1987-01-01

    Iron and iron compounds--including mammalian hemoglobins--catalyze hydroxyl radical production and lipid peroxidation. To determine whether hemoglobin-mediated lipid peroxidation might be important in hemorrhagic injuries to the central nervous system (CNS), we studied the effects of purified hemoglobin on CNS homogenates and injected hemoglobin into the spinal cords of anesthetized cats. Hemoglobin markedly inhibits Na/K ATPase activity in CNS homogenates and spinal cords of living cats. Hemoglobin also catalyzes substantial peroxidation of CNS lipids. Importantly, the potent iron chelator, desferrioxamine, blocks these adverse effects of hemoglobin, both in vitro and in vivo. Because desferrioxamine is not known to interact with heme iron, these results indicate that free iron, derived from hemoglobin, is the proximate toxic species. Overall, our data suggest that hemoglobin, released from red cells after trauma, can promote tissue injury through iron-dependent mechanisms. Suppression of this damage by desferrioxamine suggests a rational therapeutic approach to management of trauma-induced CNS injury. Images PMID:3027133

  14. Net charge and oxygen affinity of human hemoglobin are independent of hemoglobin concentration

    PubMed Central

    1978-01-01

    The dependence of net charge and oxygen affinity of human hemoglobin upon hemoglobin concentration was reinvestigated. In contrast to earlier reports from various laboratories, both functional properties of hemoglobin were found to be independent of hemoglobin concentration. Two findings indicate a concentration-independent net charge of carbonmonoxy hemoglobin at pH 6.6: (A) The pH value of a given carbonmonoty hemoglobin solution remains constant at 6.6 when the hemoglobin concentration is raised from 10 to 40 g/dl, indicating that there is no change in protonation of titratable groups of hemoglobin: (b) the net charge of carbonmonoxy hemoglobin as estimated from the Donnan distribution of 22Na+ shows no dependence on hemoglobin concentration in this concentration range. The oxygen affinity of human hemoglobin was determined from measurements of oxygen concentrations in equilibrated samples using a Lex-O2-Con apparatus (Lexington Instruments, Waltham, Mass.). P50 averaged 11.4 mm Hg at 37 degrees C, pH = 7.2, and ionic strength approximately 0.15. Neither P50 nor Hill's n showed any variation with hemoglobin concentrations increasing from 10 to 40 g/dl. PMID:32221

  15. Spectrophotometric Properties of Hemoglobin: Classroom Applications.

    ERIC Educational Resources Information Center

    Frary, Roger

    1997-01-01

    Discusses simple and safe techniques that can be used in the educational laboratory to study hemoglobin. Discusses the spectral properties of hemoglobin, spectral-absorbence curves of oxyhemoglobin and carboxyhemoglobin, tracking the conversion of oxyhemoglobin to methemoglobin, and changing from the oxyhemoglobin to deoxyhemoglobin conformation.…

  16. Blood glycated hemoglobin evaluation in sick dogs.

    PubMed Central

    Marca, M C; Loste, A; Unzueta, A; Pérez, M

    2000-01-01

    Blood glycated hemoglobin concentration reflects long-term serum glucose levels in dogs. In this study, the effects of several diseases on blood glycated hemoglobin levels have been evaluated. For this study, blood samples were drawn from 93 unhealthy dogs. The animals were distributed into 10 groups according to pathological process (group 1, digestive problems; group 2, leishmaniasis; group 3, anemia; group 4, dermatological disorders; group 5, urinary problems; group 6, cardiorespiratory problems; group 7, diabetes mellitus; group 8, insulinoma; group 9, general diseases; group 10, control group). Blood glucose and glycated hemoglobin concentrations and hemoglobin and hematocrit values were analyzed in all the animals. In diabetic dogs, a strong increase in blood glycated hemoglobin was observed when compared with the other groups (P < 0.01). In contrast, dogs with insulinoma showed a decrease in blood glycated hemoglobin, though significant differences were not reported in all cases. No change in blood glycated hemoglobin concentrations were reported in dogs affected by other diseases. So, we can suppose that only the chronic alterations in glucose metabolism (chronic hyper- or hypoglycemia) can induce significant changes on the blood glycated hemoglobin concentrations in dogs. PMID:10805256

  17. Determination of Human Hemoglobin Derivatives.

    PubMed

    Attia, Atef M M; Ibrahim, Fatma A A; Abd El-Latif, Noha A; Aziz, Samir W; Abdelmottaleb Moussa, Sherif A; Elalfy, Mohsen S

    2015-01-01

    The levels of the inactive hemoglobin (Hb) pigments [such as methemoglobin (metHb), carboxyhemoglobin (HbCO) and sulfohemoglobin (SHb)] and the active Hb [in the oxyhemoglobin (oxyHb) form] as well as the blood Hb concentration in healthy non pregnant female volunteers were determined using a newly developed multi-component spectrophotometric method. The results of this method revealed values of SHb% in the range (0.0727-0.370%), metHb% (0.43-1.0%), HbCO% (0.4-1.52%) and oxyHb% (97.06-98.62%). Furthermore, the results of this method revealed values of blood Hb concentration in the range (12.608-15.777 g/dL). The method is highly sensitive, accurate and reproducible.

  18. Monoclonal antibodies specific for sickle cell hemoglobin

    SciTech Connect

    Jensen, R.H.; Vanderlaan, M.; Grabske, R.J.; Branscomb, E.W.; Bigbee, W.L.; Stanker, L.H.

    1985-01-01

    Two mouse hybridoma cell lines were isolated which produce monoclonal antibodies that bind hemoglobin S. The mice were immunized with peptide-protein conjugates to stimulate a response to the amino terminal peptide of the beta chain of hemoglobin S, where the single amino acid difference between A and S occurs. Immunocharacterization of the antibodies shows that they bind specifically to the immunogen peptide and to hemoglobin S. The specificity for S is high enough that one AS cell in a mixture with a million AA cells is labeled by antibody, and such cells can be analyzed by flow cytometry. Immunoblotting of electrophoretic gels allows definitive identification of hemoglobin S as compared with other hemoglobins with similar electrophoretic mobility. 12 references, 4 figures.

  19. The Biochemistry of Vitreoscilla hemoglobin

    PubMed Central

    Stark, Benjamin C.; Dikshit, Kanak L.; Pagilla, Krishna R.

    2012-01-01

    The hemoglobin (VHb) from Vitreoscilla was the first bacterial hemoglobin discovered. Its structure and function have been extensively investigated, and engineering of a wide variety of heterologous organisms to express VHb has been performed to increase their growth and productivity. This strategy has shown promise in applications as far-ranging as the production of antibiotics and petrochemical replacements by microorganisms to increasing stress tolerance in plants. These applications of “VHb technology” have generally been of the “black box” variety, wherein the endpoint studied is an increase in the levels of a certain product or improved growth and survival. Their eventual optimization, however, will require a thorough understanding of the various functions and activities of VHb, and how VHb expression ripples to affect metabolism more generally. Here we review the current knowledge of these topics. VHb's functions all involve oxygen binding (and often delivery) in one way or another. Several biochemical and structure-function studies have provided an insight into the molecular details of this binding and delivery. VHb activities are varied. They include supply of oxygen to oxygenases and the respiratory chain, particularly under low oxygen conditions; oxygen sensing and modulation of transcription factor activity; and detoxification of NO, and seem to require interactions of VHb with “partner proteins”. VHb expression affects the levels of ATP and NADH, although not enormously. VHb expression may affect the level of many compounds of intermediary metabolism, and, apparently, alters the levels of expression of many genes. Thus, the metabolic changes in organisms engineered to express VHb are likely to be numerous and complicated. PMID:24688662

  20. Structure-function relations of human hemoglobins

    PubMed Central

    2006-01-01

    In 1949 Pauling and his associates showed that sickle cell hemoglobin (HbS) belonged to an abnormal molecular species. In 1958 Ingram, who used a two-dimensional system of electrophoresis and chromatography to break down the hemoglobin molecule into a mixture of smaller peptides, defined the molecular defect in HbS by showing that it differed from normal adult hemoglobin by only a single peptide. Since then, more than 200 variant and abnormal hemoglobins have been described. Furthermore, the construction of an atomic model of the hemoglobin molecule based on a high-resolution x-ray analysis by Dr. Max Perutz at Cambridge has permitted the study of the stereochemical part played by the amino acid residues, which were replaced, deleted, or added to in each of the hemoglobin variants. Some of the variants have been associated with clinical conditions. The demonstration of a molecular basis for a disease was a significant turning point in medicine. A new engineered hemoglobin derived from crocodile blood, with markedly reduced oxygen affinity and increased oxygen delivery to the tissues, points the way for future advances in medicine. PMID:17252042

  1. Oxygen Measurements in Liposome Encapsulated Hemoglobin

    NASA Astrophysics Data System (ADS)

    Phiri, Joshua Benjamin

    Liposome encapsulated hemoglobins (LEH's) are of current interest as blood substitutes. An analytical methodology for rapid non-invasive measurements of oxygen in artificial oxygen carriers is examined. High resolution optical absorption spectra are calculated by means of a one dimensional diffusion approximation. The encapsulated hemoglobin is prepared from fresh defibrinated bovine blood. Liposomes are prepared from hydrogenated soy phosphatidylcholine (HSPC), cholesterol and dicetylphosphate using a bath sonication method. An integrating sphere spectrophotometer is employed for diffuse optics measurements. Data is collected using an automated data acquisition system employing lock-in -amplifiers. The concentrations of hemoglobin derivatives are evaluated from the corresponding extinction coefficients using a numerical technique of singular value decomposition, and verification of the results is done using Monte Carlo simulations. In situ measurements are required for the determination of hemoglobin derivatives because most encapsulation methods invariably lead to the formation of methemoglobin, a nonfunctional form of hemoglobin. The methods employed in this work lead to high resolution absorption spectra of oxyhemoglobin and other derivatives in red blood cells and liposome encapsulated hemoglobin (LEH). The analysis using singular value decomposition method offers a quantitative means of calculating the fractions of oxyhemoglobin and other hemoglobin derivatives in LEH samples. The analytical methods developed in this work will become even more useful when production of LEH as a blood substitute is scaled up to large volumes.

  2. Hemoglobin-based red blood cell substitutes.

    PubMed

    Chang, Thomas Ming Swi

    2004-09-01

    Polyhemoglobin is already well into the final stages of clinical trials in humans with one approved for routine clinical use in South Africa. Conjugated hemoglobin is also in ongoing clinical trials. Meanwhile, recombinant Hb has been modified to modulate the effects of nitric oxide. Other systems contain antioxidant enzymes for those clinical applications that may have potential problems related to ischemia-reperfusion injuries. Other developments are based on hemoglobin-lipid vesicles and also the use of nanotechnology and biodegradable copolymers to prepare nanodimension artificial red blood cells containing hemoglobin and complex enzyme systems.

  3. Blood Test: Hemoglobin A1C

    MedlinePlus

    ... the person's average blood sugar levels over that time. Why It's Done Doctors use the hemoglobin A1c test to determine if your child's diabetes management plan needs to be adjusted. Typically the test ...

  4. Nanobiotechnology for hemoglobin-based blood substitutes.

    PubMed

    Chang, T M S

    2009-04-01

    Nanobiotechnology is the assembling of biological molecules into nanodimension complexes. This has been used for the preparation of polyhemoglobin formed by the assembling of hemoglobin molecules into a soluble nanodimension complex. New generations of this approach include the nanobiotechnological assembly of hemoglobin, catalase, and superoxide dismutase into a soluble nanodimension complex. This acts as an oxygen carrier and an antioxidant for those conditions with potential for ischemiareperfusion injuries. Another recent novel approach is the assembling of hemoglobin and fibrinogen into a soluble nanodimension polyhemoglobin-fibrinogen complex that acts as an oxygen carrier with platelet-like activity. This is potentially useful in cases of extensive blood loss requiring massive replacement using blood substitutes, resulting in the need for the replacement of platelets and clotting factors. A further step is the preparation of nanodimension artificial red blood cells that contain hemoglobin and all the enzymes present in red blood cells.

  5. Hemoglobins, programmed cell death and somatic embryogenesis.

    PubMed

    Hill, Robert D; Huang, Shuanglong; Stasolla, Claudio

    2013-10-01

    Programmed cell death (PCD) is a universal process in all multicellular organisms. It is a critical component in a diverse number of processes ranging from growth and differentiation to response to stress. Somatic embryogenesis is one such process where PCD is significantly involved. Nitric oxide is increasingly being recognized as playing a significant role in regulating PCD in both mammalian and plant systems. Plant hemoglobins scavenge NO, and evidence is accumulating that events that modify NO levels in plants also affect hemoglobin expression. Here, we review the process of PCD, describing the involvement of NO and plant hemoglobins in the process. NO is an effector of cell death in both plants and vertebrates, triggering the cascade of events leading to targeted cell death that is a part of an organism's response to stress or to tissue differentiation and development. Expression of specific hemoglobins can alter this response in plants by scavenging the NO, thus, interrupting the death process. Somatic embryogenesis is used as a model system to demonstrate how cell-specific expression of different classes of hemoglobins can alter the embryogenic process, affecting hormone synthesis, cell metabolite levels and genes associated with PCD and embryogenic competence. We propose that plant hemoglobins influence somatic embryogenesis and PCD through cell-specific expression of a distinct plant hemoglobin. It is based on the premise that both embryogenic competence and PCD are strongly influenced by cellular NO levels. Increases in cellular NO levels result in elevated Zn(2+) and reactive-oxygen species associated with PCD, but they also result in decreased expression of MYC2, a transcription factor that is a negative effector of indoleacetic acid synthesis, a hormone that positively influences embryogenic competence. Cell-specific hemoglobin expression reduces NO levels as a result of NO scavenging, resulting in cell survival.

  6. Cloned Hemoglobin Genes Enhance Growth Of Cells

    NASA Technical Reports Server (NTRS)

    Khosla, Chaitan; Bailey, James E.

    1991-01-01

    Experiments show that portable deoxyribonucleic acid (DNA) sequences incorporated into host cells make them produce hemoglobins - oxygen-binding proteins essential to function of red blood cells. Method useful in several biotechnological applications. One, enhancement of growth of cells at higher densities. Another, production of hemoglobin to enhance supplies of oxygen in cells, for use in chemical reactions requiring oxygen, as additive to serum to increase transport of oxygen, and for binding and separating oxygen from mixtures of gases.

  7. Evolution of ruminant hemoglobins. Thermodynamic divergence of ox and buffalo hemoglobins.

    PubMed

    Giardina, B; Arevalo, F; Clementi, M E; Ferrara, L; Di Luccia, A; Lendaro, E; Bellelli, A; Condò, S G

    1992-03-01

    The ligand-binding properties of hemoglobins from two homozygote phenotypes (AA and BB) of water buffalo (Bubalus bubalis) have been characterized by equilibrium and kinetic techniques. In the case of the BB phenotype, the two constituent hemoglobins have been purified and separately analysed. Buffalo hemoglobins display the reduced sensitivity to organic phosphates characteristic of ruminant hemoglobins, their physiological effector probably being the chloride ion. In contrast to the other known hemoglobins from ruminants, all the hemoglobins from the water buffalo display a significant temperature sensitivity, the delta H for oxygen binding in the presence of physiological effectors approaching that of human hemoglobin (delta H = -30.5 kJ/mol O2). This discrepancy with the other ruminant hemoglobins (e.g. ox, delta H = -10.4 kJ/mol O2), whose primary structure is very similar to that of buffalo, hemoglobins might be correlated to the different habitat and phylogenetic history of the two subfamilies (Bos and Bubalus) of Bovidae.

  8. Enteral and parenteral feeding influences mortality after hemoglobin-E. coli peritonitis in normal rats.

    PubMed

    Kudsk, K A; Stone, J M; Carpenter, G; Sheldon, G F

    1983-07-01

    Enteral feeding with 25% dextrose-4.25% Freamine II (TPN) improves the survival of malnourished animals to normal levels after hemoglobin-E. coli adjuvant peritonitis, whereas intravenous feeding does not. To determine whether intravenous feeding maintained a high survival rate in previously well-nourished animals, 81 rats received TPN via gastrostomy or intravenous infusion for 12 days. They were then fasted for 24 hours and given a septic challenge. Gastrostomy-fed animals survived the challenge significantly better than intravenously fed animals. Enteral feeding appears to be important in producing a high survival rate after hemoglobin-E. coli adjuvant peritonitis.

  9. Hemoglobin parameters from diffuse reflectance data

    PubMed Central

    Mourant, Judith R.; Marina, Oana C.; Hebert, Tiffany M.; Kaur, Gurpreet; Smith, Harriet O.

    2014-01-01

    Abstract. Tissue vasculature is altered when cancer develops. Consequently, noninvasive methods of monitoring blood vessel size, density, and oxygenation would be valuable. Simple spectroscopy employing fiber optic probes to measure backscattering can potentially determine hemoglobin parameters. However, heterogeneity of blood distribution, the dependence of the tissue-volume-sampled on scattering and absorption, and the potential compression of tissue all hinder the accurate determination of hemoglobin parameters. We address each of these issues. A simple derivation of a correction factor for the absorption coefficient, μa, is presented. This correction factor depends not only on the vessel size, as others have shown, but also on the density of blood vessels. Monte Carlo simulations were used to determine the dependence of an effective pathlength of light through tissue which is parameterized as a ninth-order polynomial function of μa. The hemoglobin bands of backscattering spectra of cervical tissue are fit using these expressions to obtain effective blood vessel size and density, tissue hemoglobin concentration, and oxygenation. Hemoglobin concentration and vessel density were found to depend on the pressure applied during in vivo acquisition of the spectra. It is also shown that determined vessel size depends on the blood hemoglobin concentration used. PMID:24671524

  10. Subunit dissociations in natural and recombinant hemoglobins.

    PubMed

    Manning, L R; Jenkins, W T; Hess, J R; Vandegriff, K; Winslow, R M; Manning, J M

    1996-04-01

    A precise and rapid procedure employing gel filtration on Superose-12 to measure the tetramer-dimer dissociation constants of some natural and recombinant hemoglobins in the oxy conformation is described. Natural sickle hemoglobin was chosen to verify the validity of the results by comparing the values with those reported using an independent method not based on gel filtration. Recombinant sickle hemoglobin, as well as a sickle double mutant with a substitution at the Val-6(beta) receptor site, had approximately the same dissociation constant as natural sickle hemoglobin. Of the two recombinant hemoglobins with amino acid replacements in the alpha 1 beta 2 subunit interface, one was found to be extensively dissociated and the other completely dissociated. In addition, the absence of an effect of the allosteric regulators DPG and IHP on the dissociation constant was demonstrated. Thus, a tetramer dissociation constant can now be determined readily and used together with other criteria for characterization of hemoglobins and their interaction with small regulatory molecules. PMID:8845768

  11. AMINO ACIDS AND HEMOGLOBIN PRODUCTION IN ANEMIA

    PubMed Central

    Whipple, G. H.; Robscheit-Robbins, F. S.

    1940-01-01

    Certain individual amino acids when given to standard anemic dogs cause an increase in new hemoglobin production. Occasional negative experiments are recorded. Glycine, glutamic acid, aspartic acid, cystine, histidine, phenylalanine, and proline when given in 1 gm. doses daily for 2 weeks, increase hemoglobin output on the average 23 to 25 gm. above the control level. This reaction amounts to 25 to 30 per cent of the new hemoglobin produced by the feeding of 300 gm. liver daily for 2 weeks—a standard liver test. Alanine, valine, isoleucine, and arginine in the same dosage increase the hemoglobin output on the average 13 to 17 gm. per 2 weeks over the control level. Leucine, methionine, lysine, tryptophane, and tyrosine fall in a middle group with hemoglobin output of about 20 gm. Isovaleric acid, β-hydroxybutyric acid, glutaric acid, and asparagine have shown positive effects and the butyrate is unusually potent for hemoglobin production (Table 2). The isomeric and dl-synthetic forms of the amino acids are as effectively utilized in this reaction as are the natural forms. PMID:19870982

  12. 21 CFR 864.7500 - Whole blood hemoglobin assays.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Whole blood hemoglobin assays. 864.7500 Section... blood hemoglobin assays. (a) Identification. A whole blood hemoglobin assay is a device consisting or... hemoglobin content of whole blood for the detection of anemia. This generic device category does not...

  13. 21 CFR 864.7500 - Whole blood hemoglobin assays.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Whole blood hemoglobin assays. 864.7500 Section... blood hemoglobin assays. (a) Identification. A whole blood hemoglobin assay is a device consisting or... hemoglobin content of whole blood for the detection of anemia. This generic device category does not...

  14. 21 CFR 864.7500 - Whole blood hemoglobin assays.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Whole blood hemoglobin assays. 864.7500 Section... blood hemoglobin assays. (a) Identification. A whole blood hemoglobin assay is a device consisting or... hemoglobin content of whole blood for the detection of anemia. This generic device category does not...

  15. 21 CFR 864.7500 - Whole blood hemoglobin assays.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Whole blood hemoglobin assays. 864.7500 Section... blood hemoglobin assays. (a) Identification. A whole blood hemoglobin assay is a device consisting or... hemoglobin content of whole blood for the detection of anemia. This generic device category does not...

  16. 21 CFR 864.7500 - Whole blood hemoglobin assays.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Whole blood hemoglobin assays. 864.7500 Section... blood hemoglobin assays. (a) Identification. A whole blood hemoglobin assay is a device consisting or... hemoglobin content of whole blood for the detection of anemia. This generic device category does not...

  17. 21 CFR 866.5470 - Hemoglobin immunological test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Hemoglobin immunological test system. 866.5470... Hemoglobin immunological test system. (a) Indentification. A hemoglobin immunological test system is a device... hemoglobin (the oxygen-carrying pigment in red blood cells) in blood, urine, plasma, or other body...

  18. 21 CFR 866.5470 - Hemoglobin immunological test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Hemoglobin immunological test system. 866.5470... Hemoglobin immunological test system. (a) Indentification. A hemoglobin immunological test system is a device... hemoglobin (the oxygen-carrying pigment in red blood cells) in blood, urine, plasma, or other body...

  19. The renal handling of hemoglobin. I. Glomerular filtration.

    PubMed

    Bunn, H F; Esham, W T; Bull, R W

    1969-05-01

    The glomerular filtration of hemoglobin (alpha(2)beta(2)) was studied under conditions in which its dissociation into alphabeta dimers was experimentally altered. Rats receiving hemoglobin treated with the sulfhydryl reagent bis(N-maleimidomethyl) ether (BME) showed a much lower renal excretion and prolonged plasma survival as compared with animals injected with untreated hemoglobin. Plasma disappearance was also prolonged in dogs receiving BME hemoglobin. Gel filtration data indicated that under physiological conditions, BME hemoglobin had impaired subunit dissociation. In addition, BME hemoglobin showed a very high oxygen affinity and a decreased rate of auto-oxidation. Glomerular filtration was enhanced under conditions which favor the dissociation of hemoglobin into dimers. Cat hemoglobin, which forms subunits much more extensively than canine hemoglobin, was excreted more readily by the rat kidney. The renal uptake of (59)Fe hemoglobin injected intra-arterially into rabbits varied inversely with the concentration of the injected dose.

  20. Anion Bohr effect of human hemoglobin.

    PubMed

    Bucci, E; Fronticelli, C

    1985-01-15

    The pH dependence of oxygen affinity of hemoglobin (Bohr effect) is due to ligand-linked pK shifts of ionizable groups. Attempt to identify these groups has produced controversial data and interpretations. In a further attempt to clarify the situation, we noticed that hemoglobin alkylated in its liganded form lost the Bohr effect while hemoglobin alkylated in its unliganded form showed the presence of a practically unmodified Bohr effect. In spite of this difference, analyses of the extent of alkylation of the two compounds failed to identify the presence of specific preferential alkylations. In particular, the alpha 1 valines and beta 146 histidines appeared to be alkylated to the same extent in the two proteins. Focusing our attention on the effect of the anions on the functional properties of hemoglobin, we measured the Bohr effect of untreated hemoglobin in buffers made with HEPES [N-(2-hydroxyethyl)piperazine-N'-2-ethanesulfonic acid], MES [2-(N-morpholino)ethanesulfonic acid], and MOPS [3-(N-morpholino)propanesulfonic acid], which being zwitterions do not need addition of chlorides or other anions for reaching the desired pH. The shape acquired by the Bohr effect curves, either as pH dependence of oxygen affinity or as pH dependence of protons exchanged with the solution, was irreconcilable with that of the Bohr effect curves in usual buffers. This indicated the relevance of solvent components in determining the functional properties of hemoglobin. A new thermodynamic model is proposed for the Bohr effect that includes the interaction of hemoglobin with solvent components. The classic proton Bohr effect is a special case of the new theory.

  1. Properties of Hemoglobin Solutions in Red Cells

    PubMed Central

    Gary-Bobo, C. M.; Solomon, A. K.

    1968-01-01

    The present studies are concerned with a detailed examination of the apparent anomalous osmotic behavior of human red cells. Red cell water has been shown to behave simultaneously as solvent water for nonelectrolytes and nonsolvent water, in part, for electrolytes. The nonsolvent properties are based upon assumptions inherent in the conventional van't Hoff equation. However, calculations according to the van't Hoff equation give osmotic volumes considerably in excess of total cell water when the pH is lowered beyond the isoelectric point for hemoglobin; hence the van't Hoff equation is inapplicable for the measurement of the solvent properties of the red cell. Furthermore, in vitro measurements of osmotic and other properties of 3.7 millimolal solutions of hemoglobin have failed to reveal the presence of any salt exclusion. A new hypothesis has been developed from thermodynamic principles alone, which predicts that, at constant pH, the net charge on the hemoglobin molecule decreases with increased hemoglobin concentration. The existence of such cooperative interaction may be inferred from the effect of pH on the changes in hemoglobin net charge as the spacing between the molecules decreases. The resultant movement of counterions across the cell membrane causes the apparent anomalous osmotic behavior. Quantitative agreement has been found between the anion shift predicted by the equation and that observed in response to osmotic gradients. The proposed mechanism appears to be operative in a variety of tissues and could provide an electrical transducer for osmotic signals. PMID:5688085

  2. Classification of the Disorders of Hemoglobin

    PubMed Central

    Forget, Bernard G.; Bunn, H. Franklin

    2013-01-01

    Over the years, study of the disorders of hemoglobin has served as a paradigm for gaining insights into the cellular and molecular biology, as well as the pathophysiology, of inherited genetic disorders. To date, more than 1000 disorders of hemoglobin synthesis and/or structure have been identified and characterized. Study of these disorders has established the principle of how a mutant genotype can alter the function of the encoded protein, which in turn can lead to a distinct clinical phenotype. Genotype/phenotype correlations have provided important understanding of pathophysiological mechanisms of disease. Before presenting a brief overview of these disorders, we provide a summary of the structure and function of hemoglobin, along with the mechanism of assembly of its subunits, as background for the rationale and basis of the different categories of disorders in the classification. PMID:23378597

  3. Characterization of Polyethylene Glycol Modified Hemoglobins

    NASA Astrophysics Data System (ADS)

    Salazar, Gil; Barr, James; Morgan, Wayne; Ma, Li

    2011-03-01

    Polyethylene glycol modified hemoglobins (PEGHbs) was characterized by liquid chromatography and fluorescence methods. We prepared four samples of two different molecular weight PEG, 5KDa and 20KDa, modified bovine and human hemoglobin. We studied the oxygen affinities, stabilities, and peroxidase activities of PEGHbs. We have related oxygen affinities with different degrees of modifications. The data showed that the modification on the beta subunits was less stable than that of the alpha subunits on the human Hb based samples especially. We also compared peroxidase activities among different modified PEGHbs.

  4. Asymptomatic child heterozygous for hemoglobin S and hemoglobin Pôrto Alegre.

    PubMed

    Lojo, Liliana; Santiago-Borrero, Pedro; Rivera, Enid; Renta, Jessicca; Cadilla, Carmen L

    2011-03-01

    Hemoglobin Pôrto Alegre (PA) is a rare hemoglobin resulting from a mutation in β9(A6)Ser → Cys. We describe an asymptomatic Puerto Rican female with combined heterozygosity for Hb PA and Hb S. Since birth, she has maintained normal hemoglobin, bilirubin, LDH levels, and reticulocyte count. Peripheral smear evaluation has revealed normal erythrocyte morphology with no changes suggestive of hemolysis. We conclude that the presence of Hb PA does not increase the risk of red blood cell sickling in patients who carry the Hb S mutation.

  5. Asymptomatic Child Heterozygous for Hemoglobin S and Hemoglobin Pôrto Alegre

    PubMed Central

    Lojo, Liliana; Santiago-Borrero, Pedro; Rivera, Enid; Renta, Jessicca; Cadilla, Carmen L

    2013-01-01

    Hemoglobin Pôrto Alegre (PA) is a rare hemoglobin resulting from a mutation in β9(A6)Ser→Cys. We describe an asymptomatic Puerto Rican female with combined heterozygosity for Hb PA and Hb S. Since birth, she has maintained normal hemoglobin, bilirubin, LDH levels, and reticulocyte count. Peripheral smear evaluation has revealed normal erythrocyte morphology with no changes suggestive of hemolysis. We conclude that the presence of Hb PA does not increase the risk of red blood cell sickling in patients who carry the Hb S mutation. PMID:21225927

  6. Unrecognized hemoglobin SE disease as microcytosis

    PubMed Central

    Cooper, Barry; Guileyardo, Joseph; Mora, Adan

    2016-01-01

    Hemoglobin SE disease was first described during the 1950s as a relatively benign microcytosis, but increasing prevalence has revealed a predisposition towards vasoocclusive sickling. Recognition of SE hemoglobinopathies’ potential complications is crucial so medical measures can be utilized to avoid multiorgan injury. PMID:27365881

  7. Metastable Polymerization of Sickle Hemoglobin in Droplets

    PubMed Central

    Aprelev, Alexey; Weng, Weijun; Zakharov, Mikhail; Rotter, Maria; Yosmanovich, Donna; Kwong, Suzanna; Briehl, Robin W.; Ferrone, Frank A.

    2007-01-01

    Sickle cell disease arises from a genetic mutation of one amino acid in each of the two hemoglobin β chains, leading to the polymerization of hemoglobin in the red cell upon deoxygenation, and is characterized by vascular crises and tissue damage due to the obstruction of small vessels by sickled cells. It has been an untested assumption that, in red cells that sickle, the growing polymer mass would consume monomers until the thermodynamically well-described monomer solubility was reached. By photolyzing droplets of sickle hemoglobin suspended in oil we find that polymerization does not exhaust the available store of monomers, but stops prematurely, leaving the solutions in a supersaturated, metastable state typically 20% above solubility at 37°C, though the particular values depend on the details of the experiment. We propose that polymer growth stops because the growing ends reach the droplet edge, whereas new polymer formation is thwarted by long nucleation times, since the hemoglobin concentration is lowered by depletion of monomers into the polymers that have formed. This finding suggests a new aspect to the pathophysiology of sickle cell disease, namely, that cells deoxygenated in the microcirculation are not merely undeformable, but will actively wedge themselves tightly against the walls of the microvasculature by a ratchet-like mechanism driven by the supersaturated solution. PMID:17493634

  8. Circular dichroism and conformation of fish hemoglobins.

    PubMed

    Greenwood, C; Gibson, Q H

    1983-04-10

    The circular dichroism spectrum of fully liganded CO hemoglobin from the Atlantic bluefin tuna (Tunnus thynnus) shows a pH- and temperature-dependent feature at 416 nm. It is half-developed at pH 5.9 and 20 degrees C and its change with temperature corresponds to a heat of 34 kcal/mol (tetramer) for the transition. Correlation with studies on function (Morris, R. J., and Gibson, Q. H. (1982) J. Biol. Chem. 257, 4869-4874) shows that the dichroism feature changes at about 1 pH unit below the R-T transition. There is a close correlation between the 416 nm band and changes in circular dichroism at 287 nm. The new 416 nm band is seen in several fish hemoglobins, but not with human hemoglobin. With hemoglobin from Brevoortia tyrannus, which has been sufficiently studied to permit the comparison, there is a smaller gap between the change in dichroism spectrum and the functional R-T transition. So far, no change in function has been associated with the appearance of the 416 nm circular dichroism band. PMID:6833248

  9. Hemoglobin: A Nitric-Oxide Dioxygenase

    PubMed Central

    Gardner, Paul R.

    2012-01-01

    Members of the hemoglobin superfamily efficiently catalyze nitric-oxide dioxygenation, and when paired with native electron donors, function as NO dioxygenases (NODs). Indeed, the NOD function has emerged as a more common and ancient function than the well-known role in O2 transport-storage. Novel hemoglobins possessing a NOD function continue to be discovered in diverse life forms. Unique hemoglobin structures evolved, in part, for catalysis with different electron donors. The mechanism of NOD catalysis by representative single domain hemoglobins and multidomain flavohemoglobin occurs through a multistep mechanism involving O2 migration to the heme pocket, O2 binding-reduction, NO migration, radical-radical coupling, O-atom rearrangement, nitrate release, and heme iron re-reduction. Unraveling the physiological functions of multiple NODs with varying expression in organisms and the complexity of NO as both a poison and signaling molecule remain grand challenges for the NO field. NOD knockout organisms and cells expressing recombinant NODs are helping to advance our understanding of NO actions in microbial infection, plant senescence, cancer, mitochondrial function, iron metabolism, and tissue O2 homeostasis. NOD inhibitors are being pursued for therapeutic applications as antibiotics and antitumor agents. Transgenic NOD-expressing plants, fish, algae, and microbes are being developed for agriculture, aquaculture, and industry. PMID:24278729

  10. Trematode hemoglobins show exceptionally high oxygen affinity.

    PubMed

    Kiger, L; Rashid, A K; Griffon, N; Haque, M; Moens, L; Gibson, Q H; Poyart, C; Marden, M C

    1998-08-01

    Ligand binding studies were made with hemoglobin (Hb) isolated from trematode species Gastrothylax crumenifer (Gc), Paramphistomum epiclitum (Pe), Explanatum explanatum (Ee), parasitic worms of water buffalo Bubalus bubalis, and Isoparorchis hypselobagri (Ih) parasitic in the catfish Wallago attu. The kinetics of oxygen and carbon monoxide binding show very fast association rates. Whereas oxygen can be displaced on a millisecond time scale from human Hb at 25 degrees C, the dissociation of oxygen from trematode Hb may require a few seconds to over 20 s (for Hb Pe). Carbon monoxide dissociation is faster, however, than for other monomeric hemoglobins or myoglobins. Trematode hemoglobins also show a reduced rate of autoxidation; the oxy form is not readily oxidized by potassium ferricyanide, indicating that only the deoxy form reacts rapidly with this oxidizing agent. Unlike most vertebrate Hbs, the trematodes have a tyrosine residue at position E7 instead of the usual distal histidine. As for Hb Ascaris, which also displays a high oxygen affinity, the trematodes have a tyrosine in position B10; two H-bonds to the oxygen molecule are thought to be responsible for the very high oxygen affinity. The trematode hemoglobins display a combination of high association rates and very low dissociation rates, resulting in some of the highest oxygen affinities ever observed.

  11. 21 CFR 522.1125 - Hemoglobin glutamer-200 (bovine).

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Hemoglobin glutamer-200 (bovine). 522.1125 Section... § 522.1125 Hemoglobin glutamer-200 (bovine). (a) Specifications. Each 125 milliliter bag contains 13 grams per deciliter of polymerized hemoglobin of bovine origin in modified Lactated Ringer's...

  12. 21 CFR 522.1125 - Hemoglobin glutamer-200 (bovine).

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Hemoglobin glutamer-200 (bovine). 522.1125 Section... § 522.1125 Hemoglobin glutamer-200 (bovine). (a) Specifications. Each 125 milliliter bag contains 13 grams per deciliter of polymerized hemoglobin of bovine origin in modified Lactated Ringer's...

  13. 21 CFR 522.1125 - Hemoglobin glutamer-200 (bovine).

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Hemoglobin glutamer-200 (bovine). 522.1125 Section... § 522.1125 Hemoglobin glutamer-200 (bovine). (a) Specifications. Each 125 milliliter bag contains 13 grams per deciliter of polymerized hemoglobin of bovine origin in modified Lactated Ringer's...

  14. 21 CFR 864.7455 - Fetal hemoglobin assay.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Fetal hemoglobin assay. 864.7455 Section 864.7455 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... hemoglobin polypeptide chains). The hemoglobin determination may be made by methods such as...

  15. 21 CFR 864.7455 - Fetal hemoglobin assay.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Fetal hemoglobin assay. 864.7455 Section 864.7455 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... hemoglobin polypeptide chains). The hemoglobin determination may be made by methods such as...

  16. 21 CFR 864.7455 - Fetal hemoglobin assay.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Fetal hemoglobin assay. 864.7455 Section 864.7455 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... hemoglobin polypeptide chains). The hemoglobin determination may be made by methods such as...

  17. 21 CFR 864.7455 - Fetal hemoglobin assay.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Fetal hemoglobin assay. 864.7455 Section 864.7455 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... hemoglobin polypeptide chains). The hemoglobin determination may be made by methods such as...

  18. Bioimaging techniques for subcellular localization of plant hemoglobins and measurement of hemoglobin-dependent nitric oxide scavenging in planta.

    PubMed

    Hebelstrup, Kim H; Østergaard-Jensen, Erik; Hill, Robert D

    2008-01-01

    Plant hemoglobins are ubiquitous in all plant families. They are expressed at low levels in specific tissues. Several studies have established that plant hemoglobins are scavengers of nitric oxide (NO) and that varying the endogenous level of hemoglobin in plant cells negatively modulates bioactivity of NO generated under hypoxic conditions or during cellular signaling. Earlier methods for determination of hemoglobin-dependent scavenging in planta were based on measuring activity in whole plants or organs. Plant hemoglobins do not contain specific organelle localization signals; however, earlier reports on plant hemoglobin have demonstrated either cytosolic or nuclear localization, depending on the method or cell type investigated. We have developed two bioimaging techniques: one for visualization of hemoglobin-catalyzed scavenging of NO in specific cells and another for visualization of subcellular localization of green fluorescent protein-tagged plant hemoglobins in transformed Arabidopsis thaliana plants.

  19. Universal metastability of sickle hemoglobin polymerization

    NASA Astrophysics Data System (ADS)

    Weng, Weijun

    Sickle hemoglobin (HbS) is a natural mutation of the normal hemoglobin (HbA) found in the red blood cells of human body. Polymerization of HbS occurs when the concentration of deoxyHbS exceeds a well-defined solubility, which is the underlying cause of the Sickle Cell Disease. It has long been assumed that thermodynamic equilibrium is reached when polymerization comes to an end. However, in this thesis we demonstrate that in confined volume as well as in bulk solution, HbS polymerization terminates prematurely, leaving the solution in a metastable state. A newly developed Reservoir method as well as modulated excitation method were adopted for the study. This discovery of universal metastability gives us new insights into understanding the mechanism of sickle cell disease.

  20. Serum ferritin levels in hemoglobin H disease.

    PubMed

    Galanello, R; Melis, M A; Paglietti, E; Cornacchia, G; de Virgiliis, S; Cao, A

    1983-01-01

    This study shows that hemoglobin H disease patients aged between 0.5 and 44 years, usually (27 out of 30) have normal serum ferritin levels according to age. This reconfirms that in this disease there are usually normal iron stores. However, in a few patients (3 out of 30) increased levels were found. This may be due to inappropriate iron medication, transfusions or associated idiopathic hereditary hemocromatosis gene.

  1. Free heme and sickle hemoglobin polymerization

    NASA Astrophysics Data System (ADS)

    Uzunova, Veselina V.

    This work investigates further the mechanism of one of the most interesting of the protein self-assembly systems---the polymerization of sickle hemoglobin and the role of free heme in it. Polymerization of sickle hemoglobin is the primary event in the pathology of a chronic hemolytic condition called sickle cell anemia with complex pathogenesis, unexplained variability and symptomatic treatment. Auto-oxidation develops in hemoglobin solutions exposed to room temperature and causes release of ferriheme. The composition of such solutions is investigated by mass spectrometry. Heme dimers whose amount corresponds to the initial amounts of heme released from the protein are followed. Differences in the dimer peak height are established for hemoglobin variants A, S and C and depending on the exposure duration. The effects of free heme on polymerization kinetics are studied. Growth rates and two characteristic parameters of nucleation are measured for stored Hb S. After dialysis of polymerizing solutions, no spherulites are detected at moderately high supersaturation and prolonged exposure times. The addition of 0.16-0.26 mM amounts of heme to dialyzed solutions leads to restoration of polymerization. The measured kinetic parameters have higher values compared to the ones before dialysis. The amount of heme in non-dialyzed aged solution is characterized using spectrophotometry. Three methods are used: difference in absorbance of dialyzed and non-dialyzed solutions, characteristic absorbance of heme-albumin complex and absorbance of non-dialyzed solutions with added potassium cyanide. The various approaches suggest the presence of 0.12 to 0.18 mM of free ferriheme in such solutions. Open questions are whether the same amounts of free heme are present in vivo and whether the same mechanism operates intracellulary. If the answer to those questions is positive, then removal of free heme from erythrocytes can influence their readiness to sickle.

  2. Imidazolidinone adducts of peptides and hemoglobin

    SciTech Connect

    San George, R.C.; Hoberman, H.D.

    1986-05-01

    Acetaldehyde reacts selectively with the terminal amino groups of the ..cap alpha.. and ..beta.. chains of hemoglobin to form stable adducts, the structures of which, based on /sup 13/C NMR studies, are proposed to be diastereomeric 2-methyl imidazolidin-4-ones. In this scheme, acetaldelhyde forms a reversible Schiff base with the ..cap alpha..-amino groups of the polypeptide chains which cyclize with the amide nitrogen of the first peptide bond to form the stable imidazolidinone adducts. In support of this mechanism, the authors found that in following the reaction of the peptide val-gly-gly with (1,2-/sup 13/C) acetaldehyde, /sup 13/C NMR resonances attributed to a Schiff base (delta = 170 ppm) were observed which slowly disappeared prior to appearance of resonances from a pair of stable adducts (delta = 70 and 71 ppm) believed to be the diastereomeric imidazolidinones. Schiff base formation appeared to limit the overall rate. Tetraglycine reacted in a similar manner but with a resonance from a single stable adduct observed representing the enantiomeric imidazolidinone adducts of this peptide. Peptides with proline in position 2 should be incapable of forming imidazolidinones, and the authors found that ala-pro-gly did in fact fail to form a stable adduct with acetaldehyde. The 2-methyl imidazolidin-4-one adducts of hemoglobin may be useful in determining the contribution of the amino terminal groups to the structure and functional properties of hemoglobins.

  3. Hemoglobin concentration in men with type 2 diabetes mellitus.

    PubMed

    Harusato, Ichiko; Fukui, Michiaki; Tanaka, Muhei; Shiraishi, Emi; Senmaru, Takafumi; Sakabe, Kazumi; Yamazaki, Masahiro; Hasegawa, Goji; Nakamura, Naoto

    2010-06-01

    Anemia is a common but often overlooked complication of diabetes. We investigated the relationship between hemoglobin concentration and various factors as well as markers of subclinical atherosclerosis in men with type 2 diabetes mellitus. Hemoglobin concentration was measured in 319 men with type 2 diabetes mellitus. We evaluated the relationship between hemoglobin concentration and various factors including age, body mass index, and glycemic control, as well as between hemoglobin concentration and pulse wave velocity or ankle-brachial index (n = 209) and between hemoglobin concentration and carotid intima-media thickness or plaque score (n = 125). Mean hemoglobin concentration was 14.2 +/- 0.80 g/dL. Body mass index (r = 0.340, P < .0001) and estimated glomerular filtration rate (r = 0.219, P = .0011) were positively associated with hemoglobin concentration, whereas age (r = -0.388, P < .0001), glycated albumin (r = -0.148, P = .0121), serum creatinine concentration (r = -0.206, P = .0019), and log (urinary albumin excretion) (r = -0.188, P = .0010) were negatively associated with hemoglobin concentration. Multiple regression analysis identified age (beta = -0.222, P = .0019), body mass index (beta = 0.145, P = .0432), systolic blood pressure (beta = 0.214, P = .0015), total cholesterol concentration (beta = 0.170, P = .0077), and serum creatinine concentration (beta = -0.181, P = .0045) as independent determinants of hemoglobin concentration. No significant association was observed between hemoglobin concentration and serum erythropoietin concentration (r = -0.079, P = .2980). Negative correlations were found between hemoglobin concentration and pulse wave velocity (r = -0.289, P < .0001) and between hemoglobin concentration and plaque score (r = -0.275, P = .0024). In conclusion, hemoglobin concentration was associated with various factors; and decreased hemoglobin concentration was associated with subclinical markers of atherosclerosis in men with type 2

  4. Studies of hemoglobin denaturation and Heinz body formation in the unstable hemoglobins.

    PubMed

    Winterbourn, C C; Carrell, R W

    1974-09-01

    The sequential changes that occur during the precipitation on mild heating of the unstable hemoglobins, Hb Christchurch, Hb Sydney, Hb Köln, and Hb A, were examined with particular attention to the possibility of an accompanying oxidative process. Hb Christchurch, Hb Sydney, and Hb A precipitated with equal amounts of alpha- and beta-chains and full heme complement. Hb Köln, however, was one-half hemedepleted and showed a slight excess of precipitated beta-chains. In all cases the spectrum of the precipitated material was typical of a hemichrome. There was no evidence that sulfhydryl oxidation contributed to the precipitation process. Reduced glutathione was unable to protect the hemoglobin against precipitation, and mixed disulfide formation between the precipitating hemoglobin and glutathione was insignificant, even in the presence of excess glutathione. No blockade of beta93 cysteines could be demonstrated in the unstable hemoglobins. Precipitation of oxyhemoglobin and carboxyhemoglobin in all cases gave nonspecific oxidation of approximately two of the six hemoglobin sulfhydryl groups to give intra- and intermolecular disulfide bonds. Single alpha- and beta-chains, plus polymers of up to five or six chains linked by disulfide bridges, were demonstrated by polyacrylamide gel electrophoresis. This disulfide oxidation was not observed with deoxy- or methemoglobin and did not appear to influence the rate of precipitation. These findings fit the theoretical prediction that autoxidation of oxy- and carboxyhemoglobin is accompanied by formation of a free radical, with the reactions of this free radical being confined intramolecularly.Together, these results are in keeping with predictions based on the known structural abnormalities of the unstable hemoglobins, all of which result in greater molecular flexibility. Our findings support the conclusion that the usual precipitating event is altered bonding at the heme to give the formation of hemichromes. There is no

  5. Possibilities of Using Fetal Hemoglobin as a Platform for Producing Hemoglobin-Based Oxygen Carriers (HBOCs).

    PubMed

    Ratanasopa, Khuanpiroon; Cedervall, Tommy; Bülow, Leif

    2016-01-01

    The expression levels of fetal hemoglobin (HbF) in bacterial recombinant systems are higher compared with normal adult hemoglobin (HbA). However, heme disorientation in globins are often observed in recombinant production processes, both for HbA and HbF, although the degree of heme oriental disorder is much lower for HbF. In addition, the heme disorientation can be converted to a normal conformation by an oxidation-reduction process. A chromatographic cleaning process involving a strong anion exchanger can be utilized to remove such unstable and nondesirable forms of Hb.

  6. Mini-hemoglobins from nemertean worms.

    PubMed

    Vandergon, Thomas L; Riggs, Austen F

    2008-01-01

    Hemoglobins (Hbs) found in members of the phylum Nemertea are smaller than any other known Hb molecules. These mini-Hbs have been of great interest because of their unique three-dimensional structure and their stable ligand-binding properties. Also of interest is the expression of mini-Hb in neural tissue, body wall muscle tissue, and red blood cells. This chapter outlines methods that may be used to isolate and purify functional mini-Hbs from all three tissue types in nemertean worms.

  7. Neutral changes during divergent evolution of hemoglobins

    NASA Technical Reports Server (NTRS)

    Jukes, T. H.

    1978-01-01

    A comparison of the mRNAs for rabbit and human beta-hemoglobins shows that synonymous changes in codons have accumulated three times as rapidly as nucleotide replacements that produced changes in amino acids. This agrees with predictions based on the so-called neutral theory. In addition, seven codon changes that appear to be single-base changes (according to maximum parsimony) are actually two-base changes. This indicates that the construction of primordial sequences is of limited significance when based on inferences that assume minimum base changes for amino acid replacements.

  8. Polymeric nanoparticles for hemoglobin-based oxygen carriers.

    PubMed

    Piras, Anna Maria; Dessy, Alberto; Chiellini, Federica; Chiellini, Emo; Farina, Claudio; Ramelli, Massimiliano; Della Valle, Elena

    2008-10-01

    This article reports on the current status of the research on blood substitutes with particular attention on hemoglobin-based oxygen carriers (HBOCs). Insights on the physiological role of hemoglobin are reported in the view of the development of both acellular and cellular hemoglobin-based oxygen carriers. Attention is then focused on biocompatible polymeric materials that find application as matrices for cellular based HBOCs and on the strategies employed to avoid methemoglobin formation. Results are reported regarding the use of bioerodible polymeric matrices based on hemiesters of alternating copolymer (maleic anhydride-co-butyl vinyl ether) for the preparation of hemoglobin loaded nanoparticles.

  9. WAXS studies of the structural diversity of hemoglobin in solution.

    SciTech Connect

    Makowski, L.; Bardhan, J.; Gore, D.; Lal, J.; Mandava, S.; Park, S.; Rodi, D. J.; Ho, N. T.; Ho, C.; Fischetti, R. F.

    2011-01-01

    Specific ligation states of hemoglobin are, when crystallized, capable of taking on multiple quaternary structures. The relationship between these structures, captured in crystal lattices, and hemoglobin structure in solution remains uncertain. Wide-angle X-ray solution scattering (WAXS) is a sensitive probe of protein structure in solution that can distinguish among similar structures and has the potential to contribute to these issues. We used WAXS to assess the relationships among the structures of human and bovine hemoglobins in different liganded forms in solution. WAXS data readily distinguished among the various forms of hemoglobins. WAXS patterns confirm some of the relationships among hemoglobin structures that have been defined through crystallography and NMR and extend others. For instance, methemoglobin A in solution is, as expected, nearly indistinguishable from HbCO A. Interestingly, for bovine hemoglobin, the differences between deoxy-Hb, methemoglobin and HbCO are smaller than the corresponding differences in human hemoglobin. WAXS data were also used to assess the spatial extent of structural fluctuations of various hemoglobins in solution. Dynamics has been implicated in allosteric control of hemoglobin, and increased dynamics has been associated with lowered oxygen affinity. Consistent with that notion, WAXS patterns indicate that deoxy-Hb A exhibits substantially larger structural fluctuations than HbCO A. Comparisons between the observed WAXS patterns and those predicted on the basis of atomic coordinate sets suggest that the structures of Hb in different liganded forms exhibit clear differences from known crystal structure.

  10. Characterization of the hemoglobin of the backswimmer Anisops deanei (Hemiptera).

    PubMed

    Wawrowski, Agnes; Matthews, Philip G D; Gleixner, Eva; Kiger, Laurent; Marden, Michael C; Hankeln, Thomas; Burmester, Thorsten

    2012-09-01

    While O(2)-binding hemoglobin-like proteins are present in many insects, prominent amounts of hemoglobin have only been found in a few species. Backswimmers of the genera Anisops and Buenoa (Notonectidae) have high concentrations of hemoglobin in the large tracheal cells of the abdomen. Oxygen from the hemoglobin is delivered to a gas bubble and controls the buoyant density, which enables the bugs to maintain their position without swimming and to remain stationary in the mid-water zone where they hunt for prey. We have obtained the cDNA sequences of three Anisops deanei hemoglobin chains by RT-PCR and RACE techniques. The deduced amino acid sequences show an unusual insertion of a single amino acid in the conserved helix E, but this does not affect protein stability or ligand binding kinetics. Recombinant A. deanei hemoglobin has an oxygen affinity of P(50) = 2.4 kPa (18 torr) and reveals the presence of a dimeric fraction or two different conformations. The absorption spectra demonstrate that the Anisops hemoglobin is a typical pentacoordinate globin. Phylogenetic analyses show that the backswimmer hemoglobins evolved within Heteroptera and most likely originated from an intracellular hemoglobin with divergent function. PMID:22575160

  11. 21 CFR 864.7470 - Glycosylated hemoglobin assay.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... diabetes and to determine the proper insulin dosage for a patient. Elevated levels of glycosylated hemoglobin indicate uncontrolled diabetes in a patient. (b) Classification. Class II (performance standards)....

  12. 21 CFR 864.7470 - Glycosylated hemoglobin assay.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... diabetes and to determine the proper insulin dosage for a patient. Elevated levels of glycosylated hemoglobin indicate uncontrolled diabetes in a patient. (b) Classification. Class II (performance standards)....

  13. 21 CFR 864.7470 - Glycosylated hemoglobin assay.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... diabetes and to determine the proper insulin dosage for a patient. Elevated levels of glycosylated hemoglobin indicate uncontrolled diabetes in a patient. (b) Classification. Class II (performance standards)....

  14. 21 CFR 864.7470 - Glycosylated hemoglobin assay.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... diabetes and to determine the proper insulin dosage for a patient. Elevated levels of glycosylated hemoglobin indicate uncontrolled diabetes in a patient. (b) Classification. Class II (performance standards)....

  15. 21 CFR 864.7470 - Glycosylated hemoglobin assay.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... diabetes and to determine the proper insulin dosage for a patient. Elevated levels of glycosylated hemoglobin indicate uncontrolled diabetes in a patient. (b) Classification. Class II (performance standards)....

  16. A review of variant hemoglobins interfering with hemoglobin A1c measurement.

    PubMed

    Little, Randie R; Roberts, William L

    2009-05-01

    Hemoglobin A1c (HbA1c) is used routinely to monitor long-term glycemic control in people with diabetes mellitus, as HbA1c is related directly to risks for diabetic complications. The accuracy of HbA1c methods can be affected adversely by the presence of hemoglobin (Hb) variants or elevated levels of fetal hemoglobin (HbF). The effect of each variant or elevated HbF must be examined with each specific method. The most common Hb variants worldwide are HbS, HbE, HbC, and HbD. All of these Hb variants have single amino acid substitutions in the Hb beta chain. HbF is the major hemoglobin during intrauterine life; by the end of the first year, HbF falls to values close to adult levels of approximately 1%. However, elevated HbF levels can occur in certain pathologic conditions or with hereditary persistence of fetal hemoglobin. In a series of publications over the past several years, the effects of these four most common Hb variants and elevated HbF have been described. There are clinically significant interferences with some methods for each of these variants. A summary is given showing which methods are affected by the presence of the heterozygous variants S, E, C, and D and elevated HbF. Methods are divided by type (immunoassay, ion-exchange high-performance liquid chromatography, boronate affinity, other) with an indication of whether the result is artificially increased or decreased by the presence of a Hb variant. Laboratorians should be aware of the limitations of their method with respect to these interferences.

  17. Alkaline Bohr effect of human hemoglobin Ao.

    PubMed

    Di Cera, E; Doyle, M L; Gill, S J

    1988-04-01

    Differential oxygen binding measurements obtained over the pH range 6.95 to 9.10 at 25 degrees C have allowed a detailed description of the alkaline Bohr effect of human hemoglobin Ao. Phenomenological analysis of the data in terms of the Adair equation shows that: (1) the oxygen binding curves are asymmetrical with the population of the triply oxygenated species being negligible throughout the pH range studied: (2) the shape of the oxygen binding curve is affected by pH, especially at low saturation; and (3) the maximum O2-proton linkage is -0.52 mole of proton per mole of oxygen at pH 7.4. A possible molecular mechanism of the Bohr effect is proposed within the framework of an allosteric model which accounts for the low population of triply oxygenated hemoglobin species. At least three Bohr groups are necessary for a quantitative description of the alkaline Bohr effect. Two of these groups titrate in the range of the His146 beta and Vall alpha residues, which have long been identified as the main alkaline Bohr groups, and altogether contribute 84% of the alkaline Bohr effect at physiological pH. A third ionizable group, linked to oxygenation presumably at the beta chains, is implicated and is titrated in a pH range characteristic of a surface histidyl residue.

  18. Hemoglobin alpha in the blood vessel wall

    PubMed Central

    Butcher, Joshua T.; Johnson, Tyler; Beers, Jody; Columbus, Linda; Isakson, Brant E

    2014-01-01

    Hemoglobin has been studied and well haracterized in red blood cells for over one hundred years. However, new work has indicated that the hemoglobin alpha subunit (Hbα) is also found within the blood vessel wall, where it appears to localize at the myoendothelial junction (MEJ) and plays a role in regulating nitric oxide (NO) signaling between endothelium and smooth muscle. This discovery has created a new paradigm for control of endothelial nitric oxide synthase activity, nitric oxide diffusion, and ultimately, control of vascular tone and blood pressure. This review will discuss the current knowledge of hemoglobin’s properties as a gas exchange molecule in the blood stream, and extrapolate the properties of Hbα biology to the MEJ signaling domain. Specifically, we propose that Hbα is present at the MEJ to regulate NO release and diffusion in a restricted physical space, which would have powerful implications for the regulation of blood flow in peripheral resistance arteries. PMID:24832680

  19. Rare hemoglobin variants in Tunisian population.

    PubMed

    Zorai, A; Moumni, I; Mosbahi, I; Douzi, K; Chaouachi, D; Guemira, F; Abbes, S

    2015-04-01

    During the last 30 years, many studies concerning hemoglobinopathies were realized among Tunisians. More than twenty different thalassemic alleles were detected on the β-globin gene, and less are affecting the α-globin genes. Unusual hemoglobin (Hb) variants other than Hb S, Hb C, and Hb O-arab, which are the most frequent variants in Tunisia, were also detected. Eight Tunisian subjects were studied at phenotypic and molecular levels. Hematological indices and hemoglobin (Hb) pattern were performed by alkaline electrophoresis and isoelectric focusing (IEF),and the Hb fractions were quantitated by cation exchange HPLC. On genomic level, coding regions were amplified by polymerase chain reaction (PCR) followed by a sequencing of the purified PCR products using the dye terminator method. Seven uncommon Hb variants were detected and described for the first time among Tunisians. HbA2-Tunis [δ46(CD5), Gly → Glu, GGG → GAG] is the newly described δ-chain variant in our laboratory, and some other variants (Hb Constant Spring, G San Jose, and Hb J-Bangkok) are very uncommon in the Mediterranean region. We present here an updated review of the Hb variants detected among Tunisians. Twenty-one rare Hb variants were detected affecting the α1-, α2-, δ-, γ-, and β-globin genes, leading in some cases to a severe phenotype especially when the stability is completely altered. The ethnical history of Tunisia could explain this important variability of the observed rare Hb variants. PMID:24905386

  20. Liposome-encapsulated hemoglobin processing methods.

    PubMed

    Zheng, S; Zheng, Y; Beissinger, R L; Fresco, R

    1992-01-01

    An effective and safe red blood cell substitute is being developed based on double emulsion/evaporation techniques followed by high pressure homogenization to form liposome-encapsulated hemoglobin (LEH). Formulations are made up of hydrogenated phosphatidylcholine (PC, soy or egg), cholesterol, phosphatidylinositol (PI), and alpha-tocopherol in a molar ratio of 1:1:0.2:0.02, respectively. Resulting LEH-encapsulated hemoglobin (Hb) concentrations are greater than 80% of precursor Hb solutions. Met-Hb generation accompanying LEH processing appears to be small with only a 3% increase for encapsulated over precursor. These results correspond to an oxygen content for an LEH suspension sample (50% by volume LEH) of 15 volume% oxygen. Oxygen affinity and cooperativity values for LEH suspensions appear to be near the normal values expected for whole blood. The viscosity of LEH suspension samples (50% by volume LEH in phosphate-buffered saline containing 7.5 wt% albumin) were slightly higher than that of whole blood. The effect of shear rate on leakage of encapsulated Hb from LEH was small, i.e. 0.5% or less. Nearly total isovolemic exchange transfusion using a cannulated rat model demonstrates efficacy of LEH suspension samples. There appears to be no difference in rat internal organ weights between rats exchanged with control compared to rats exchanged with LEH. Circulation half-life following 50% isovolemic exchange-transfusion is about 15 to 18 hours. PMID:1391451

  1. Hemoglobin switching in sheep and goats: occurrence of hemoglobins A and C in the same red cell.

    PubMed

    Nienhuis, A W; Bunn, H F

    1974-09-13

    Sheep and goats switch from the synthesis of hemoglobin A (alpha(2)beta(2)(A)) to hemoglobin C (alpha(2)beta(2)(C)) when made anemic. We have demonstrated the existence of the asymmetrical hybrid hemoglobin, alpha(2)beta(A)beta(C), in the circulating red cells of anemic sheep. These erythroid cells, therefore, synthesized both A and C hemoglobin simultaneously. Thus, the switch appears to be mediated by selective gene expression rather than by a clonal or cellular selective mechanism. PMID:4469671

  2. 21 CFR 866.5470 - Hemoglobin immunological test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... hemoglobin (the oxygen-carrying pigment in red blood cells) in blood, urine, plasma, or other body fluids. Measurements of free hemoglobin aid in the diagnosis of various hematologic disorders, such as sickle cell anemia, Fanconi's anemia (a rare inherited disease), aplastic anemia (bone marrow does not produce...

  3. Hemoglobin Screening Independently Predicts All-Cause Mortality.

    PubMed

    Fulks, Michael; Dolan, Vera F; Stout, Robert L

    2015-01-01

    Objective .- Determine if the addition of hemoglobin testing improves risk prediction for life insurance applicants. Method .- Hemoglobin results for insurance applicants tested from 1993 to 2007, with vital status determined by Social Security Death Master File follow-up in 2011, were analyzed by age and sex with and without accounting for the contribution of other test results. Results .- Hemoglobin values ≤12.0 g/dL (and possibly ≤13.0 g/dL) in females age 50+ (but not age <50) and hemoglobin values ≤13.0 g/dL in all males are associated with progressively increasing mortality risk independent of the contribution of other test values. Increased risk is also noted for hemoglobin values >15.0 g/dL (and possibly >14.0 g/dL) for all females and for hemoglobin values >16.0 g/dL for males. Conclusion .- Hemoglobin testing can add additional independent risk assessment to that obtained from other laboratory testing, BP and build in this relatively healthy insurance applicant population. Multiple studies support this finding at older ages, but data (and the prevalence of diseases impacting hemoglobin levels) are limited at younger ages. PMID:27584842

  4. Computation Of Facilitated Transport of O2 In Hemoglobin

    NASA Technical Reports Server (NTRS)

    Davis, Sanford

    1991-01-01

    Report describes computations of unsteady facilitated transport of oxygen through liquid membrane of hemoglobin. Used here, "facilitated transport" means diffusion of permeant through membrane in which that diffusion enhanced by reversible chemical reaction between permeant and membrane. In this case, reversible reactions between hemoglobin and oxygen.

  5. Hemoglobin Screening Independently Predicts All-Cause Mortality.

    PubMed

    Fulks, Michael; Dolan, Vera F; Stout, Robert L

    2015-01-01

    Objective .- Determine if the addition of hemoglobin testing improves risk prediction for life insurance applicants. Method .- Hemoglobin results for insurance applicants tested from 1993 to 2007, with vital status determined by Social Security Death Master File follow-up in 2011, were analyzed by age and sex with and without accounting for the contribution of other test results. Results .- Hemoglobin values ≤12.0 g/dL (and possibly ≤13.0 g/dL) in females age 50+ (but not age <50) and hemoglobin values ≤13.0 g/dL in all males are associated with progressively increasing mortality risk independent of the contribution of other test values. Increased risk is also noted for hemoglobin values >15.0 g/dL (and possibly >14.0 g/dL) for all females and for hemoglobin values >16.0 g/dL for males. Conclusion .- Hemoglobin testing can add additional independent risk assessment to that obtained from other laboratory testing, BP and build in this relatively healthy insurance applicant population. Multiple studies support this finding at older ages, but data (and the prevalence of diseases impacting hemoglobin levels) are limited at younger ages.

  6. On the fate of extracellular hemoglobin and heme in brain.

    PubMed

    Lara, Flavio A; Kahn, Suzana A; da Fonseca, Anna Cc; Bahia, Carlomagno P; Pinho, João Pc; Graca-Souza, Aurélio V; Houzel, Jean C; de Oliveira, Pedro L; Moura-Neto, Vivaldo; Oliveira, Marcus F

    2009-06-01

    Intracerebral hemorrhage (ICH) is a major cause of disability in adults worldwide. The pathophysiology of this syndrome is complex, involving both inflammatory and redox components triggered by the extravasation of blood into the cerebral parenchyma. Hemoglobin, heme, and iron released therein seem be important in the brain damage observed in ICH. However, there is a lack of information concerning hemoglobin traffic and metabolism in brain cells. Here, we investigated the fate of hemoglobin and heme in cultured neurons and astrocytes, as well as in the cortex of adult rats. Hemoglobin was made traceable by conjugation to Alexa 488, whereas a fluorescent heme analogue (tin-protoporphyrin IX) was prepared to allow heme tracking. Using fluorescence microscopy we observed that neurons were more efficient in uptake hemoglobin and heme than astrocytes. Exposure of cortical neurons to hemoglobin or heme resulted in an oxidative stress condition. Viability assays showed that neurons were more susceptible to both hemoglobin and heme toxicity than astrocytes. Together, these results show that neurons, rather than astrocytes, preferentially take up hemoglobin-derived products, indicating that these cells are actively involved in the ICH-associated brain damage.

  7. Combinatorics of giant hexagonal bilayer hemoglobins.

    PubMed

    Hanin, L G; Vinogradov, S N

    2000-01-01

    The paper discusses combinatorial and probabilistic models allowing to characterize various aspects of spacial symmetry and structural heterogeneity of the giant hexagonal bilayer hemoglobins (HBL Hb). Linker-dodecamer configurations of HBL are described for two and four linker types (occurring in the two most studied HBL Hb of Arenicola and Lumbricus, respectively), and the most probable configurations are found. It is shown that, for HBL with marked dodecamers, the number of 'normal-marked' pairs of dodecamers in homological position follows a binomial distribution. The group of symmetries of the dodecamer substructure of HBL is identified with the dihedral group D6. Under natural symmetry assumptions, the total dipole moment of the dodecamer substructure of HBL is shown to be zero. Biological implications of the mathematical findings are discussed.

  8. Stroma-free hemoglobin from bovine blood.

    PubMed

    Lima, Maria Celiana P; Andrade, Cristina T

    2007-01-01

    Isolation and purification of bovine hemoglobin (HbBv) was carried out after reaction of whole blood with carbon monoxide. Washing/centrifugation steps were used to eliminate leukocytes, platelets, and plasma proteins. Hypotonic media and ultrasound radiation were used to lyse red blood cells. Lyse by ultrasound was shown to lead to solutions at the highest concentrations in HbBv, and the least concentrations in major phospholipids contaminants. Additional purification procedures were performed to remove membrane proteins and phospholipids. In the first case, proteins were denatured by thermal treatment, and filtered. To eliminate phospholipids, liquid chromatography was used with strong anion exchangers. Purity of HbBv was evaluated by normal phase high performance liquid chromatography (HPLC), electrophoresis, and size-exclusion HPLC. PMID:17701489

  9. Separation and characterization of Menhaden hemoglobin components.

    PubMed

    Pokrywka, G S; Gold, F

    1980-01-01

    Hemolysate from Brevoortia tyrannus (Atlantic Menhaden) consists of two major and two minor components, as determined by ion-exchange chromatography. Oxygen equilibria, flash photolysis and rapid mixing techniques are used to detect functional differences between the two major components, revealing a system analogous to the Trout I-IV system. Menhaden IV exhibits a moderate Root effect and is sensitive to organic phosphate inhibition. Menhaden I exhibits little sensitivity to pH changes or the presence of organic phosphates. These differences are probably based on contrasting kinetic behavior, subunit heterogeneity and replacement of a COOH-terminal histidine residue. Theories accounting for the significance of functional hemoglobin multiplicity are reviewed. By bypassing the normal physiological unloading mechanisms, Menhaden I may be functioning as an oxygen reservoir, perhaps for red muscle during periods of high activity. PMID:7353958

  10. Computational Study on Hemoglobin Protein Family

    NASA Astrophysics Data System (ADS)

    Craciun, Dana; Isvoran, Adriana; Avram, Nicolae M.

    2009-05-01

    We have analyzed 19 proteins belonging to hemoglobin protein family: 3 for plants, 4 for invertebrates and the others for vertebrates. For every protein we have determined the following parameters: the fractal dimension of its backbone, the fractal dimension of its surface, the radius of gyration, the area of its molecular surface and the area of the surface of its cavities. At global level, we did not notice significant differences for the fractal parameters for proteins belonging to different organisms and it underlines that all these proteins perform the same biological function. We have obtained different values of the local and global surface fractal dimensions reflecting distinct roughness of protein pockets in comparison to the entire surface, also in good correlation with the biological function. The geometric characteristics are distinct for the three investigated families of proteins.

  11. Effect of hydrostatic pressure on ligand binding to hemoglobin.

    PubMed

    Carey, F G; Knowles, F; Gibson, Q H

    1977-06-25

    Increase in hydrostatic pressure to 1000 atm increased the affinity of human and menhaden (Brevoortia tyrannus) hemoglobins for oxygen. With necessary assumptions about the form of the equilibrium curve, and after correction for changes in pH and volume due to pressure, the increase in affinity is about 2-fold for both hemoglobins. At pH 6.5, Hill's n for menhaden hemoglobin is near 1, and it is believed to remain in the T state, whereas human hemoglobin undergoes a T to R transition. This suggests that the R-T equilibrium is not disturbed by pressure. In direct experiments the binding of a fluorescent effector (8 hydroxy-1,3,6-pyrene (trisulfonic acid) to deoxyhemoglobin was not changed by pressure. The binding of n-butylisocyanide to hemoglobin and to myoglobin is also greater at high pressures, similarly suggesting that the R-T transition is not involved in the pressure effect. PMID:16924

  12. Hydroxylation and dealkylation reactions catalyzed by hemoglobin.

    PubMed

    Mieyal, J J; Starke, D W

    1994-01-01

    Red blood cells contain many enzymes that are akin to those that catalyze xenobiotic metabolism in liver and other tissues. An obvious exception is the cytochrome P-450 system that is found in virtually all other tissues. In vitro studies, however, have shown that hemoglobin can be a broad monooxygenase catalyst, exhibiting the properties of a monooxygenase enzyme. Thus, catalysis by Hb displays typical Michaelis-Menten kinetics, dependence on the native protein, coupling to NADPH-dependent flavoprotein reductases, and inhibition by carbon monoxide. The reconstituted system containing Hb along with P-450 reductase utilizes NADPH and O2 to catalyze typical monooxygenase reactions, including O- and N-demethylations as well as aromatic and aliphatic hydroxylations, and the catalytic cycle appears to mimic the typical P-450 mechanism. Turnover numbers for aniline hydroxylation are similar for Hb and P-450 reconstituted systems, whereas P-450 systems are more effective for other reactions. Catalysis by Hb seems to be restricted to the beta-heme sites of the tetramer, reflecting more facile substrate access. Overall the similarities and differences between Hb and P-450 provide an opportunity to examine the basis for their differential monooxygenase or peroxidase/peroxygenase activities in a comparative manner. Hb may be especially useful in delineating the early events in the respective reaction schemes, because it can be studied in various stable redox/ligand states, including the oxyferrous form. Similar hemoglobin-catalyzed oxidative biotransformations occur within intact erythrocytes, but apparent turnover numbers are much lower than those with the reconstituted Hb system, suggesting different mechanisms of catalysis. Although Hb-mediated oxidase activity in erythrocytes is low relative to other sites of xenobiotic metabolism, it may contribute to in situ activation of xenobiotics leading to oxidative stress, disruption of sulfhydryl homeostasis in the erythrocytes

  13. Bohr effect of hemoglobins: Accounting for differences in magnitude.

    PubMed

    Okonjo, Kehinde O

    2015-09-01

    The basis of the difference in the Bohr effect of various hemoglobins has remained enigmatic for decades. Fourteen amino acid residues, identical in pairs and located at specific 'Bohr group positions' in human hemoglobin, are implicated in the Bohr effect. All 14 are present in mouse, 11 in dog, eight in pigeon and 13 in guinea pig hemoglobin. The Bohr data for human and mouse hemoglobin are identical: the 14 Bohr groups appear at identical positions in both molecules. The dog data are different from the human because three Bohr group positions are occupied by non-ionizable groups in dog hemoglobin; the pigeon data are vastly different from the human because six Bohr group positions are occupied by non-ionizable groups in pigeon hemoglobin. The guinea pig data are quite complex. Quantitative analyses showed that only the pigeon data could be fitted with the Wyman equation for the Bohr effect. We demonstrate that, apart from guinea pig hemoglobin, the difference between the Bohr effect of each of the other hemoglobins and of pigeon hemoglobin can be accounted for quantitatively on the basis of the occupation of some of their Bohr group positions by non-ionizable groups in pigeon hemoglobin. We attribute the anomalous guinea pig result to a new salt-bridge formed in its R2 quaternary structure between the terminal NH3(+) group of one β-chain and the COO(-) terminal group of the partner β-chain in the same molecule. The pKas of this NH3(+) group are 6.33 in the R2 and 4.59 in the T state.

  14. Insights into Hemoglobin Assembly through in Vivo Mutagenesis of α-Hemoglobin Stabilizing Protein*

    PubMed Central

    Khandros, Eugene; Mollan, Todd L.; Yu, Xiang; Wang, Xiaomei; Yao, Yu; D'Souza, Janine; Gell, David A.; Olson, John S.; Weiss, Mitchell J.

    2012-01-01

    α-Hemoglobin stabilizing protein (AHSP) is believed to facilitate adult Hemoglobin A assembly and protect against toxic free α-globin subunits. Recombinant AHSP binds multiple forms of free α-globin to stabilize their structures and inhibit precipitation. However, AHSP also stimulates autooxidation of αO2 subunit and its rapid conversion to a partially unfolded bishistidyl hemichrome structure. To investigate these biochemical properties, we altered the evolutionarily conserved AHSP proline 30 in recombinantly expressed proteins and introduced identical mutations into the endogenous murine Ahsp gene. In vitro, the P30W AHSP variant bound oxygenated α chains with 30-fold increased affinity. Both P30W and P30A mutant proteins also caused decreased rates of αO2 autooxidation as compared with wild-type AHSP. Despite these abnormalities, mice harboring P30A or P30W Ahsp mutations exhibited no detectable defects in erythropoiesis at steady state or during induced stresses. Further biochemical studies revealed that the AHSP P30A and P30W substitutions had minimal effects on AHSP interactions with ferric α subunits. Together, our findings indicate that the ability of AHSP to stabilize nascent α chain folding intermediates prior to hemin reduction and incorporation into adult Hemoglobin A is physiologically more important than AHSP interactions with ferrous αO2 subunits. PMID:22287545

  15. Insights into hemoglobin assembly through in vivo mutagenesis of α-hemoglobin stabilizing protein.

    PubMed

    Khandros, Eugene; Mollan, Todd L; Yu, Xiang; Wang, Xiaomei; Yao, Yu; D'Souza, Janine; Gell, David A; Olson, John S; Weiss, Mitchell J

    2012-03-30

    α-Hemoglobin stabilizing protein (AHSP) is believed to facilitate adult Hemoglobin A assembly and protect against toxic free α-globin subunits. Recombinant AHSP binds multiple forms of free α-globin to stabilize their structures and inhibit precipitation. However, AHSP also stimulates autooxidation of αO(2) subunit and its rapid conversion to a partially unfolded bishistidyl hemichrome structure. To investigate these biochemical properties, we altered the evolutionarily conserved AHSP proline 30 in recombinantly expressed proteins and introduced identical mutations into the endogenous murine Ahsp gene. In vitro, the P30W AHSP variant bound oxygenated α chains with 30-fold increased affinity. Both P30W and P30A mutant proteins also caused decreased rates of αO(2) autooxidation as compared with wild-type AHSP. Despite these abnormalities, mice harboring P30A or P30W Ahsp mutations exhibited no detectable defects in erythropoiesis at steady state or during induced stresses. Further biochemical studies revealed that the AHSP P30A and P30W substitutions had minimal effects on AHSP interactions with ferric α subunits. Together, our findings indicate that the ability of AHSP to stabilize nascent α chain folding intermediates prior to hemin reduction and incorporation into adult Hemoglobin A is physiologically more important than AHSP interactions with ferrous αO(2) subunits.

  16. The role of hemoglobin heme loss in Heinz body formation: studies with a partially heme-deficient hemoglobin and with genetically unstable hemoglobins

    PubMed Central

    Jacob, Harry S.; Winterhalter, Kaspar H.

    1970-01-01

    A number of mutant hemoglobins are inordinately unstable, denaturing in circulating red cells into Heinz bodies, resulting in congenital Heinz body hemolytic anemia (CHBHA). We have emphasized that most such hemoglobins involve amino acid substitutions at sites neighboring the heme group of the β-polypeptide chain, and have shown that heme binding to globin is diminished thereby. Thus, hemes were progressively lost from four unstable hemoglobins (Köln, Hammersmith, San Francisco, and Zürich) as they precipitated into Heinz bodies at 50°C. The role of heme loss, especially from beta chains, in Heinz body formation was supported by studies with a hemoglobin synthesized to contain hemes only on its alpha chains (α2hemeβ20). The behavior of this compound, postulated to be an intermediary in the formation of Heinz bodies, mimicked that of the genetically unstable hemoglobins in several ways: (a) it precipitated at 50°C into typical coccoid Heinz bodies; (b) as also observed with CHBHA hemoglobins this denaturation was virtually prevented by the heme ligands, cyanide or carbon monoxide, which inhibit further heme loss; it was potentiated by oxidation of hemes to the ferri- state, which accentuates heme loss; (c) the thiol groups of α2hemeβ20 were hyperreactive, forming mixed disulfides with glutathione and membrane sulfhydryls at rates similar to those of CHBHA hemoglobins and 10 or more times that of normal hemoglobin A; (d) heme repletion of the protein molecules by the addition of crystalline hemin to either α2hemeβ20 or to the genetically unstable hemoglobins, prevented their precipitation into Heinz bodies and normalized their aberrant electrophoretic behaviors; and (e) during Heinz body formation at 50°C both α2hemeβ20 and the genetically unstable hemoglobins released free αheme-chains into solution, suggesting that the bulk of the whitish, Heinz body precipitate is naked β8-chains. We conclude that heme loss from mutant beta chains is an early step

  17. Two-photon excited fluorescence emission from hemoglobin

    NASA Astrophysics Data System (ADS)

    Sun, Qiqi; Zeng, Yan; Zhang, Wei; Zheng, Wei; Luo, Yi; Qu, Jianan Y.

    2015-03-01

    Hemoglobin, one of the most important proteins in blood, is responsible for oxygen transportation in almost all vertebrates. Recently, we discovered two-photon excited hemoglobin fluorescence and achieved label-free microvascular imaging based on the hemoglobin fluorescence. However, the mechanism of its fluorescence emission still remains unknown. In this work, we studied the two-photon excited fluorescence properties of the hemoglobin subunits, heme/hemin (iron (II)/(III) protoporphyrin IX) and globin. We first studied the properties of heme and the similar spectral and temporal characteristics of heme and hemoglobin fluorescence provide strong evidence that heme is the fluorophore in hemoglobin. Then we studied the fluorescence properties of hemin, globin and methemoglobin, and found that the hemin may have the main effect on the methemoglobin fluorescence and that globin has tryptophan fluorescence like other proteins. Finally, since heme is a centrosymmetric molecule, that the Soret band fluorescence of heme and hemoglobin was not observed in the single photon process in the previous study may be due to the parity selection rule. The discovery of heme two-photon excited fluorescence may open a new window for heme biology research, since heme as a cofactor of hemoprotein has many functions, including chemical catalysis, electron transfer and diatomic gases transportation.

  18. Development of an immunoassay to detect benzene adducts in hemoglobin

    SciTech Connect

    Grassman, J.A.

    1993-01-01

    The purpose of this project was to develop an immunoassay to detect the adducts formed in hemoglobin after exposure to benzene, which is known to cause bone marrow degeneration and acute myelogenous leukemia. The use of benzene-adduct detection as a biological monitoring method would permit measurement of low exposures and exposures sustained weeks earlier. The reactivity of hydroquinone, an important benzene metabolite, with blood proteins and amino acids was investigated in order to decide which antigens and analytes were likely to be suitable for immunoassay development. The second section determined the combination of benzene-metabolite and antigen need to produce an immunoassay with the requisite low detection limit and specificity. The immunoassays with the best performance were tested on hemoglobin from benzene-exposed mice. In vitro studies showed that hydroquinone efficiently formed adducts with erythrocyte membranes and hemoglobin but not with albumin. Adduction efficiency was greater in incubations using purified hemoglobin than whole blood. Cysteine accounted for 15 to 27% of the adducts formed by hydroquinone. The site of the other adducts were not identified although there was evidence that the hemoglobin heme was adducted. Adducts were found on only 1 of the 2 globin chains. Tryptic digestion of the globin failed to associate the adducts with a specific peptide. Antigens made from hydroquinone-adducted hemoglobin but not hydroquinone-adducted cysteines coupled to carrier proteins effectively elicited adduct-specific antibodies. Interference due to reactivity to hemoglobin was controlled by using uniform quantities of hemoglobin in all wells. The mid-range of the best assays were approximately 12 pmoles HQ per well. Antibodies directed toward hemoglobin adducted with the benzene metabolites phenol, catechol and 1,2,4-trihydroxybenzene were also made. The performance of the anti-1,2,4-trihydroxybenzene were suitable for quantitative immunoassays.

  19. Functional differentiation in trematode hemoglobin isoforms.

    PubMed

    Rashid, A K; Weber, R E

    1999-03-01

    The Hbs and the major electrophoretic Hb components (isoHbs) were isolated from three species of the trematodes, Explanatum explanatum (Ee), Gastrothylax crumenifer (Gc) and Paramphistomum epiclitum (Pe), that parasitise the common Indian water buffalo Bubalus bubalis. The Hbs are monomeric and resemble the so-called nonfunctional mutant hemoglobins that have Tyr at B10 or E7 positions (replacing Leu and the His residues, respectively). However, they are capable of binding with O2 and CO. O2 equilibrium studies of trematode Hb isoforms reveal extremely high O2 affinities, with half-saturation O2 tension (P50) values up to 800 times lower than those of human hemoglobins. This correlates with Tyr residues at B10 and at the distal position (E7) that decrease the O2 dissociation rate by contributing hydrogen bonds (H-bonds) to the bound O2. These substitutions also increase the O2 association rates either due to orientation of E7-Tyr towards the solvent and/or by sterically hindering the entry of water molecules into the heme pocket. The latter may account for the low rate of autoxidation of trematode Hbs. The Hbs and their isoforms from different species exhibited pronounced variation in O2 affinity, which may relate to subtle differences in the structure of the heme pocket. The O2 affinities of the composite (unfractionated) Hbs were intermediate to those of the individual Hb isoform. The P50 values of Hbs here obtained by direct O2 equilibrium measurements differed from those calculated from kinetic data already published [Kiger, L., Rashid, A. K., Griffon, N., Haque, M., Moens, L.,Gibson, Q. H., Poyart, C., & Marden, M. C. (1998). Biophys. J. 75, 990-998.] Intermediate state(s) due to slow reorientation of E7-Tyr may account for this difference. Some Hb isoforms showed slight (either normal or reverse) Bohr effects. The hyperbolic O2 equilibrium curve, Hill coefficient (n) values near unity accord with a monomeric nature of trematode Hbs. In marked contrast to

  20. Biophysical basis of hypoxic radioprotection by deoxygenated dextran-hemoglobin

    SciTech Connect

    Wong, J.T.; Hill, R.P.

    1986-08-01

    Perfusion with deoxygenated dextran-hemoglobin provides an effective method for inducing hypoxic radioprotection of normal tissues during radiation treatment of tumors. In this study, the dependence of P50, the half-saturation pressure of oxygen binding to dextran-hemoglobin, was analyzed as a function of solution temperature and pH. The variation of attainable radioprotection with P50, and with the amount of collateral blood entering into the perfused region, was calculated. Upon perfusion of canine gracilis muscle with deoxygenated dextran-hemoglobin, a rapid onset of extensive venous hypoxia was observed.

  1. Effects of cerebral ischemia on neuronal hemoglobin

    PubMed Central

    He, Yangdong; Hua, Ya; Liu, Wenquan; Hu, Haitao; Keep, Richard F.; Xi, Guohua

    2009-01-01

    Summary The present study examined whether or not neuronal hemoglobin (Hb) is present in rats. It then examined whether cerebral ischemia or ischemic preconditioning (IPC) affects neuronal Hb levels in vivo and in vitro. In vivo, male Sprague-Dawley rats were subjected to either 15 minutes of transient middle cerebral artery occlusion with 24 hours of reperfusion, an IPC stimulus, or 24 hours of permanent middle cerebral artery occlusion (pMCAO), or IPC followed three days later by 24 hours of pMCAO. In vitro, primary cultured neurons were exposed to 2 hours of oxygen-glucose deprivation with 22 hours of reoxygenation. Results showed that Hb is widely expressed in rat cerebral neurons but not astrocytes. Hb expression was significantly upregulated in the ipsilateral caudate and the cortical core of the middle cerebral artery territory after IPC. Hb levels also increased in more penumbral cortex and the contralateral hemisphere 24 hours after pMCAO, but expression in the ipsilateral caudate and cortical core area were decreased. Ischemic preconditioning modified pMCAO-induced brain Hb changes. Neuronal Hb levels in vitro were increased by 2 hours of oxygen-glucose deprivation and 22 hours of reoxygenation. These results indicate that Hb is synthesized in neurons and can be upregulated by ischemia. PMID:19066615

  2. Influences of genetic variation on fetal hemoglobin.

    PubMed

    He, Yunyan; Lin, Weixiong; Luo, Jianming

    2011-11-01

    Fetal hemoglobin (HbF) plays a dominant role in ameliorating morbidity and mortality of hemoglobinopathies. The authors performed a replicated study following the genome-wide association study (GWAS) guidelines to identify the genetic mechanics that influence HbF. The authors recruited and phenotyped 312 unrelated β-thalassemia subjects. Single-nucleotide polymorphism (SNP) analysis was performed by using polymerase chain reaction (PCR)/restriction enzymes. Four independent regions of interest were identified: HBS1L-MYB intergenic region, BCL11A locus, β-globin gene cluster, and the CSNK2A1 gene. There were 10 SNPs associated with HbF levels. In addition, haplotypes of HBS1L-MYB and BCL11A were identified and showed association with HbF production. Three independent regions, including HBS1L-MYB intergenic region, BCL11A locus, and β-globin gene cluster, were associated with HbF levels. This study can significantly improve the GWAS findings in Chinese cohorts and is useful for further research in the field of common predictors of the erythropoiesis.

  3. Structure and evolution of Paramecium hemoglobin genes.

    PubMed

    Yamauchi, K; Tada, H; Usuki, I

    1995-10-17

    Hemoglobin (Hb) genes have been cloned from three different species of ciliated protists, P. multimicronucleatum, P. triaurelia and P. jenningsi. Southern blotting of the genomic DNAs using the P. caudatum Hb cDNA showed both intraspecies variation in different stocks of P. caudatum and interspecies variation within the genus Paramecium. The isolated Hb genes were composed of 118, 117 and 117 codons, and interrupted by a short intron with 27, 29 and 29 bp at the same position, in P. multimicronucleatum, P. triaurelia and P. jenningsi, respectively. This suggests that the one-intron and two-exon structure has been conserved in the Hb genes in this genus. The amino acid sequences of the Paramecium Hbs were more than 87% identical to one another and homologous to those from the other ciliated protists Tetrahymena thermophila and T. pyriformis, the green alga Chlamydomonas eugametos, and the cyanobacterium Nostoc commune Hbs, all of which consist of about 120 amino acid residues (120-aa group). In particular, the amino acid sequences of the P. triaurelia and P. jenningsi Hbs were the same, although there were 20 nucleotide differences between the coding regions in the two genes. A maximum likelihood inference as to the phylogenetic relationships among these genes suggests that the Paramecium Hbs genes have evolved more rapidly than the other genes in the 120-aa group, and that P. triaurelia and P. genningsi are sibling species and the P. aurelia complex became a small cell after it separated from P. jenningsi.

  4. Solid hemoglobin-polymer phantoms for evaluation of biophotonic systems.

    PubMed

    Jang, Hyounguk; Pfefer, T Joshua; Chen, Yu

    2015-09-15

    Stable tissue phantoms that incorporate the spectral absorption properties of hemoglobin would benefit a wide range of biophotonic technologies. Toward this end, we have developed and validated a novel polymer material incorporating hemoglobin. Our solid hemoglobin-polymer (SHP) material is fabricated by mixing liquid silicone base with a hemoglobin solution, followed by sonication and low temperature curing. The optical properties of samples were determined over 450-1000 nm using the inverse adding-doubling method and the Beer-Lambert law. Measurements indicated SHP optical stability over four months. Near-infrared spectroscopy and hyperspectral imaging measurements of SHP samples were performed to demonstrate the utility of this approach. SHP materials have the potential to improve tissue-simulating phantoms used for development, evaluation, and standardization of optical devices for oximetry and other applications. PMID:26371926

  5. Reverse engineering the cooperative machinery of human hemoglobin.

    PubMed

    Ren, Zhong

    2013-01-01

    Hemoglobin transports molecular oxygen from the lungs to all human tissues for cellular respiration. Its α2β2 tetrameric assembly undergoes cooperative binding and releasing of oxygen for superior efficiency and responsiveness. Over past decades, hundreds of hemoglobin structures were determined under a wide range of conditions for investigation of molecular mechanism of cooperativity. Based on a joint analysis of hemoglobin structures in the Protein Data Bank (Ren, companion article), here I present a reverse engineering approach to elucidate how two subunits within each dimer reciprocate identical motions that achieves intradimer cooperativity, how ligand-induced structural signals from two subunits are integrated to drive quaternary rotation, and how the structural environment at the oxygen binding sites alter their binding affinity. This mechanical model reveals the intricate design that achieves the cooperative mechanism and has previously been masked by inconsistent structural fluctuations. A number of competing theories on hemoglobin cooperativity and broader protein allostery are reconciled and unified.

  6. Weak binding gases as modulators of hemoglobin function

    SciTech Connect

    Schoenborn, B P; Saxena, A; North, B E

    1980-01-01

    Studies are reported in which the mechanisms of binding of inert gaseous agents to hemoglobin and myoglobin are investigated. Specific binding sites are mapped. Possible effects on sickle cell formation and oxygen binding are discussed. (ACR)

  7. The Stepwise Mutation Model: An Experimental Evaluation Utilizing Hemoglobin Variants

    PubMed Central

    Fuerst, Paul A.; Ferrell, Robert E.

    1980-01-01

    The stepwise mutation model of Ohta and Kimura (1973) was proposed to explain patterns of genetic variability revealed by means of electrophoresis. The assumption that electrophoretic mobility was principally determined by unit changes in net molecular charge has been criticized by Johnson (1974, 1977). This assumption has been tested directly using hemoglobin. Twenty-seven human hemoglobin variants with known amino acid substitutions, and 26 nonhuman hemoglobins with known sequences were studied by starch gel electrophoresis. Of these hemoglobins, 60 to 70% had electrophoretic mobilities that could be predicted solely on the basis of net charge calculated from the amino acid composition alone, ignoring tertiary structure. Only four hemoglobins showed a mobility that was clearly different from an expected mobility calculated using only the net charge of the molecule. For the remaining 30% of hemoglobins studied, mobility was determined by a combination of net charge and other unidentified components, probably reflecting changes in ionization of some amino acid residues as a result of small alterations in tertiary structure due to the amino acid substitution in the variant. For the nonhuman hemoglobins, the deviation of a sample from its expected mobility increased with increasing amino acid divergence from human hemoglobin A.—It is concluded that the net electrostatic charge of a molecule is the principal determinant of electrophoretic mobility under the conditions studied. However, because of the significant deviation from strict stepwise mobility detected for 30 to 40% of the variants studied, it is further concluded that the infinite-allele model of Kimura and Crow (1964) or a "mixed model" such as that proposed by Li (1976) may be more appropriate than the stepwise mutation model for the analysis of much of the available electrophoretic data from natural populations. PMID:17248992

  8. Monoclonal antibodies recognizing single amino acid substitutions in hemoglobin

    SciTech Connect

    Stanker, L.H.; Branscomb, E.; Vanderlaan, M.; Jensen, R.H.

    1986-06-01

    Four monoclonal antibodies (mAb) to non-human primate hemoglobin referred to as Cap-4, Cap-5, Rh-2, and Rh-4, and two mAb to human hemoglobin, referred to as H-1 and H-3 were isolated and were partially characterized. Binding studies with these mAb on a panel of hemoglobins and isolated ..cap alpha.. and ..beta.. globin chains revealed a unique reactivity pattern for each mAb. Amino acid sequence analysis of the antigens used to generate the binding data suggests that the specific recognition of certain hemoglobin antigens by each mAb is controlled by the presence of a particular amino acid at a specific position within the epitope. The use of synthetic peptides as antigens confirmed this observation for five of the mAb. No synthetic peptides were tested with the sixth mAb, Rh-2. The amino acids required for binding of mAb Cap-4, Cap-5, Rh-4, and Rh-2 to hemoglobin are alanine at ..beta..5, threonine at ..beta..13, glutamine at ..beta..125, and leucine at ..cap alpha..68. The non-human primate hemoglobin antibodies require a specific amino acid that is not present in human hemoglobin. The amino acid required for binding of Cap-4, Cap-5, and Rh-4 could arise by a single base change in the ..beta.. globin gene, whereas the amino acid required for Rh-2 binding could only occur if two base changes occurred. Thus these mAb are candidate probes for a somatic cell mutation assay on the basis of the detection of peripheral blood red cells that possess single amino acid substituted hemoglobin as a result of single base substitutions in the globin genes of precursor cells.

  9. Hemoglobin uptake by Paracoccidioides spp. is receptor-mediated.

    PubMed

    Bailão, Elisa Flávia Luiz Cardoso; Parente, Juliana Alves; Pigosso, Laurine Lacerda; de Castro, Kelly Pacheco; Fonseca, Fernanda Lopes; Silva-Bailão, Mirelle Garcia; Báo, Sônia Nair; Bailão, Alexandre Melo; Rodrigues, Marcio L; Hernandez, Orville; McEwen, Juan G; Soares, Célia Maria de Almeida

    2014-05-01

    Iron is essential for the proliferation of fungal pathogens during infection. The availability of iron is limited due to its association with host proteins. Fungal pathogens have evolved different mechanisms to acquire iron from host; however, little is known regarding how Paracoccidioides species incorporate and metabolize this ion. In this work, host iron sources that are used by Paracoccidioides spp. were investigated. Robust fungal growth in the presence of the iron-containing molecules hemin and hemoglobin was observed. Paracoccidioides spp. present hemolytic activity and have the ability to internalize a protoporphyrin ring. Using real-time PCR and nanoUPLC-MSE proteomic approaches, fungal growth in the presence of hemoglobin was shown to result in the positive regulation of transcripts that encode putative hemoglobin receptors, in addition to the induction of proteins that are required for amino acid metabolism and vacuolar protein degradation. In fact, one hemoglobin receptor ortholog, Rbt5, was identified as a surface GPI-anchored protein that recognized hemin, protoporphyrin and hemoglobin in vitro. Antisense RNA technology and Agrobacterium tumefaciens-mediated transformation were used to generate mitotically stable Pbrbt5 mutants. The knockdown strain had a lower survival inside macrophages and in mouse spleen when compared with the parental strain, which suggested that Rbt5 could act as a virulence factor. In summary, our data indicate that Paracoccidioides spp. can use hemoglobin as an iron source most likely through receptor-mediated pathways that might be relevant for pathogenic mechanisms. PMID:24831516

  10. Hemoglobin Uptake by Paracoccidioides spp. Is Receptor-Mediated

    PubMed Central

    Bailão, Elisa Flávia Luiz Cardoso; Parente, Juliana Alves; Pigosso, Laurine Lacerda; de Castro, Kelly Pacheco; Fonseca, Fernanda Lopes; Silva-Bailão, Mirelle Garcia; Báo, Sônia Nair; Bailão, Alexandre Melo; Rodrigues, Marcio L.; Hernandez, Orville; McEwen, Juan G.; Soares, Célia Maria de Almeida

    2014-01-01

    Iron is essential for the proliferation of fungal pathogens during infection. The availability of iron is limited due to its association with host proteins. Fungal pathogens have evolved different mechanisms to acquire iron from host; however, little is known regarding how Paracoccidioides species incorporate and metabolize this ion. In this work, host iron sources that are used by Paracoccidioides spp. were investigated. Robust fungal growth in the presence of the iron-containing molecules hemin and hemoglobin was observed. Paracoccidioides spp. present hemolytic activity and have the ability to internalize a protoporphyrin ring. Using real-time PCR and nanoUPLC-MSE proteomic approaches, fungal growth in the presence of hemoglobin was shown to result in the positive regulation of transcripts that encode putative hemoglobin receptors, in addition to the induction of proteins that are required for amino acid metabolism and vacuolar protein degradation. In fact, one hemoglobin receptor ortholog, Rbt5, was identified as a surface GPI-anchored protein that recognized hemin, protoporphyrin and hemoglobin in vitro. Antisense RNA technology and Agrobacterium tumefaciens-mediated transformation were used to generate mitotically stable Pbrbt5 mutants. The knockdown strain had a lower survival inside macrophages and in mouse spleen when compared with the parental strain, which suggested that Rbt5 could act as a virulence factor. In summary, our data indicate that Paracoccidioides spp. can use hemoglobin as an iron source most likely through receptor-mediated pathways that might be relevant for pathogenic mechanisms. PMID:24831516

  11. Automated quantitation of hemoglobin-based blood substitutes in whole blood samples.

    PubMed

    Kunicka, J; Malin, M; Zelmanovic, D; Katzenberg, M; Canfield, W; Shapiro, P; Mohandas, N

    2001-12-01

    It is necessary to develop methods for accurate monitoring of cell-free hemoglobin in circulation. Routine monitoring of circulating cell-free hemoglobin will be useful for evaluating the efficacy of blood substitute administration andfor determining the clearance rates of the blood substitute from circulation. In addition, discriminating between cell-free hemoglobin and cell-associated hemoglobin will enable accurate determination of RBC indices, mean cell hemoglobin and mean corpuscular hemoglobin concentration, in individuals receiving hemoglobin-based blood substitutes. As colorimetric methods used by hematology analyzers to quantitate the hemoglobin value of a blood sample cannot distinguish between cell-associated and cell-free hemoglobin, it is currently not feasible to quantitate the levels of hemoglobin substitutes in circulation. The advent of a technology that measures volume and hemoglobin concentration of individual RBCs provides an alternative strategy for quantitating the cell-associated hemoglobin in a blood sample. We document that the combined use of cell-based and colorimetric hemoglobin measurements provides accurate discrimination between cell-associated and cell-free hemoglobin over a wide range of hemoglobin levels. This strategy should enable rapid and accurate monitoring of the levels of cell-free hemoglobin substitutes in the circulation of recipients of these blood substitutes.

  12. Iron nitrosyl hemoglobin formation from the reaction of hydroxylamine and hemoglobin under physiological conditions.

    PubMed

    Lockamy, Virginia L; Shields, Howard; Kim-Shapiro, Daniel B; King, S Bruce

    2004-11-01

    Sickle cell disease patients receiving hydroxyurea (HU) therapy have shown increases in the production of nitric oxide (NO) metabolites, which include iron nitrosyl hemoglobin (HbNO), nitrite, and nitrate. However, the exact mechanism by which HU forms HbNO in vivo is not understood. Previous studies indicate that the reaction of oxyhemoglobin (oxyHb) or deoxyhemoglobin (deoxyHb) with HU are too slow to account for in vivo HbNO production. In this study, we show that the reaction of methemoglobin (metHb) with HU to form HbNO could potentially be fast enough to account for in vivo HbNO formation but competing reactions of either excess oxyHb or deoxyHb during the reaction reduces the likelihood that HbNO will be produced from the metHb-HU reaction. Using electron paramagnetic resonance (EPR) spectroscopy we have detected measurable amounts of HbNO and metHb during the reactions of oxyHb, deoxyHb, and metHb with excess hydroxylamine (HA). We also demonstrate HbNO and metHb formation from the reactions of excess oxyHb, deoxyHb, or metHb and HA, conditions that are more likely to mimic those in vivo. These results indicate that the reaction of hydroxylamine with hemoglobin produces HbNO and lend chemical support for a potential role for hydroxylamine in the in vivo metabolism of hydroxyurea.

  13. Relative phase of oscillations of cerebral oxy-hemoglobin and deoxy-hemoglobin concentrations during sleep

    NASA Astrophysics Data System (ADS)

    Pierro, Michele L.; Sassaroli, Angelo; Bergethon, Peter R.; Fantini, Sergio

    2012-02-01

    We present a near-infrared spectroscopy study of the instantaneous phase difference between spontaneous oscillations of cerebral deoxy-hemoglobin and oxy-hemoglobin concentrations ([Hb] and [HbO], respectively) in the low-frequency range, namely 0.04-0.12 Hz. We report phase measurements during the transitions between different sleep stages in a whole-night study of a human subject. We have found that the phase difference between [Hb] and [HbO] low-frequency oscillations tends to be greater in deep sleep (by ~96° on average) and REM sleep (by ~77° on average) compared to the awake state. In particular, we have observed progressive phase increases as the subject transitions from awake conditions into non-REM sleep stages N1, N2, and N3. Corresponding phase decreases were recorded in the reversed transitions from sleep stages N3 to N2, and N2 to awake. These results illustrate the physiological information content of phase measurements of [Hb] and [HbO] oscillations that reflect the different cerebral hemodynamic conditions of the different sleep stages, and that can find broader applicability in a wide range of near-infrared spectroscopy brain studies.

  14. Toxicity of hemoglobin solutions: hemoglobin is a lipopolysaccharide (LPS) binding protein which enhances LPS biological activity.

    PubMed

    Roth, R I; Kaca, W

    1994-01-01

    Administration of alpha alpha-crosslinked stroma-free hemoglobin (SFH) as a cell-free resuscitation fluid is associated with multiple organ toxicities. Many of these toxicities are characteristic of the pathophysiological effects of bacterial endotoxins (lipopolysaccharide, LPS). To better understand the potential role of LPS in the observed in vivo toxicities of SFH, we examined mixtures of SFH and E. coli LPS for evidence of LPS-SFH complex formation. LPS-SFH complexes were demonstrated by three techniques: ultrafiltration through 300 kDa cut-off membranes, which distinguished LPS in complexes (87-89% < 300 kDa) from LPS alone (90% > 300 kDa); density centrifugation through 5% sucrose, which distinguished denser LPS alone from LPS-SFH complexes; and precipitation by 67% ethanol, which demonstrated 2-3 fold increased precipitability of complexes compared to SFH alone. Interaction of LPS with SFH was also associated with markedly increased biological activity of LPS, as manifested by enhancement of LPS activation of Limulus amebocyte lysate (LAL), increased release of human mononuclear cell tissue factor, and enhanced production of cultured human endothelial cell tissue factor. These results demonstrated that hemoglobin can serve as an endotoxin binding protein, and that this interaction results in the alteration of several LPS physical characteristics and enhancement of LPS biological activities.

  15. Glycosylated hemoglobin and hyperbaric oxygen coverage denials.

    PubMed

    Moffat, A D; Worth, E R; Weaver, L K

    2015-01-01

    Some Medicaid and Medicare fiscal intermediaries are denying hyperbaric oxygen (HBO2) therapy for diabetic foot ulcer (DFU) patients if the glycosylated hemoglobin (HbA1c) > 7.0%. We performed multiple PubMed searches for any diabetic wound healing clinical trial that documented HbA1c and had a wound healing endpoint. We scrutinized 30 peer-reviewed clinical trials, representing more than 4,400 patients. The average HbA1c from the intervention side of the studies was 8.6% (7.2% - 9.9%) and the control/sham side was 8.3% (6.0% - 10.6%). Twelve studies made a direct attempt to link HbA1c and wound healing. Four retrospective studies and one prospective cohort study assert that lower HbA1c favors wound healing, but review of the studies reveal design flaws that invalidate these conclusions. In total, 25 studies showed no direct correlation between HbA1c levels and wound healing. There was no randomized controlled trial (RCT) data demonstrating that HbA1c < 7.0% improves diabetic wound healing. In every study reviewed, wounds healed with high HbA1c levels that would be considered poorly controlled by the American Diabetes Association (ADA). Frequently, patients lack optimal blood glucose control when they have a limb-threatening DFU. The evidence supports that denying hyperbaric oxygen to those with HbA1c > 7.0% is unfounded. PMID:26152104

  16. Glycosylated hemoglobin and hyperbaric oxygen coverage denials.

    PubMed

    Moffat, A D; Worth, E R; Weaver, L K

    2015-01-01

    Some Medicaid and Medicare fiscal intermediaries are denying hyperbaric oxygen (HBO2) therapy for diabetic foot ulcer (DFU) patients if the glycosylated hemoglobin (HbA1c) > 7.0%. We performed multiple PubMed searches for any diabetic wound healing clinical trial that documented HbA1c and had a wound healing endpoint. We scrutinized 30 peer-reviewed clinical trials, representing more than 4,400 patients. The average HbA1c from the intervention side of the studies was 8.6% (7.2% - 9.9%) and the control/sham side was 8.3% (6.0% - 10.6%). Twelve studies made a direct attempt to link HbA1c and wound healing. Four retrospective studies and one prospective cohort study assert that lower HbA1c favors wound healing, but review of the studies reveal design flaws that invalidate these conclusions. In total, 25 studies showed no direct correlation between HbA1c levels and wound healing. There was no randomized controlled trial (RCT) data demonstrating that HbA1c < 7.0% improves diabetic wound healing. In every study reviewed, wounds healed with high HbA1c levels that would be considered poorly controlled by the American Diabetes Association (ADA). Frequently, patients lack optimal blood glucose control when they have a limb-threatening DFU. The evidence supports that denying hyperbaric oxygen to those with HbA1c > 7.0% is unfounded.

  17. Interaction of the chlorite-based drug WF10 and chlorite with hemoglobin, methemoglobin and ferryl hemoglobin.

    PubMed

    Pichert, Annelie; Arnhold, Jürgen

    2015-11-01

    The interaction of the chlorite-based drug solution WF10 with human oxyhemoglobin and oxidized hemoglobin forms was investigated monitoring the corresponding spectral changes in heme states. The chlorite component of WF10 converts oxyhemoglobin into methemoglobin with a rate of 35.4 M(-1)s(-1). Methemoglobin is also formed upon the interaction of ferryl hemoglobin and WF10/chlorite. The rate of this interconversion depends on the oxidation state of ferryl hemoglobin. This rate is 114 M(-1)s(-1), when ferryl hemoglobin was generated upon reaction of oxyhemoglobin and hydrogen peroxide. A considerable higher rate (6600 M(-1)s(-1)) is measured between the chlorite components of WF10 and ferryl hemoglobin after formation of the latter species from methemoglobin. WF10/chlorite inactivates also methemoglobin as evidenced by the continuous decrease of the Soret band and all other absorbances with a rate of 8.3 M(-1)s(-1). In all interconversions, the chlorite component of WF10 was the active principle as shown in experiments applying pure chlorite at the same concentration as in WF10. Thus, WF10 is able to diminish efficiently the yield of cytotoxic hemoglobin species that might appear after excessive hemolysis of red blood cells under pathologic situations.

  18. Expression of fully functional tetrameric human hemoglobin in Escherichia coli.

    PubMed Central

    Hoffman, S J; Looker, D L; Roehrich, J M; Cozart, P E; Durfee, S L; Tedesco, J L; Stetler, G L

    1990-01-01

    Synthetic genes encoding the human alpha- and beta-globin polypeptides have been expressed from a single operon in Escherichia coli. The alpha- and beta-globin polypeptides associate into soluble tetramers, incorporate heme, and accumulate to greater than 5% of the total cellular protein. Purified recombinant hemoglobin has the correct stoichiometry of alpha- and beta-globin chains and contains a full complement of heme. Each globin chain also contains an additional methionine as an extension to the amino terminus. The recombinant hemoglobin has a C4 reversed-phase HPLC profile essentially identical to that of human hemoglobin A0 and comigrates with hemoglobin A0 on SDS/PAGE. The visible spectrum and oxygen affinity are similar to that of native human hemoglobin A0. The recombinant protein shows a reduction in Bohr and phosphate effects, which may be attributed to the presence of methionine at the amino termini of the alpha and beta chains. We have also expressed the alpha- and beta-globin genes separately and found that the expression of the alpha-globin gene alone results in a marked decrease in the accumulation of alpha-globin in the cell. Separate expression of the beta-globin gene results in high levels of insoluble beta-globin. These observations suggest that the presence of alpha- and beta-globin in the same cell stabilizes alpha-globin and aids the correct folding of beta-globin. This system provides a simple method for expressing large quantities of recombinant hemoglobin and allows facile manipulation of the genes encoding hemoglobin to produce functionally altered forms of this protein. Images PMID:2236062

  19. Studies in red blood cell preservation: 4. Plasma vesicle hemoglobin exceeds free hemoglobin.

    PubMed

    Greenwalt, T J; McGuinness, C G; Dumaswala, U J

    1991-01-01

    Studies were designed to find out how much of the plasma hemoglobin ( Hb) in whole blood was in microvesicles and how much was free Hb after 21 days of storage in citrate-phosphate-dextrose anticoagulant and to determine the effect of the plasticizer, di-(2-ethylhexyl)phthalate (DEHP). The total plasma Hb in polyolefin (PO) containers without DEHP was much higher than in polyvinyl chloride (PVC) with the plasticizer (p = 0.004). Less than 30% of the Hb was in free solution in either type of container. The addition of 300 micrograms/ml of DEHP to the plasma in the PO containers resulted in marked reduction in the microvesiculation (p less than 0.01) but did not affect the level of free Hb. RBC hypotonic fragility and morphology scores were significantly improved. It is concluded that microvesiculation contributes more to plasma Hb concentration than free Hb during storage. Some hemolysis of red blood cells (RBC) is expected during blood bank storage. It has been shown that part of the hemoglobin (Hb) in the suspending medium is free and part is encapsulated in microvescicles shed by the RBC [1]. The amount of hemolysis and microvesiculation that occurs has been noted to be less when blood is stored in polyvinyl chloride (PVC) containers in which di-(2-ethylhexyl)phthalate (DEHP) is used as the plasticizer [1]. The DEHP that leaches into the plasma has been shown to decrease hemolysis, microvesiculation, and the increase in osmotic fragility which RBC undergo during refrigerated storage [2-9].(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1949704

  20. Hemoglobin variability after renal transplantation is associated with mortality

    PubMed Central

    Kainz, Alexander; Wilflingseder, Julia; Függer, Reinhold; Kramar, Reinhard; Oberbauer, Rainer

    2012-01-01

    Summary Anemia is a common problem after renal transplantation. Therefore, the patients are treated with erythropoietin stimulating agents (ESAs). The varying response to treatment contributes to hemoglobin variability, which might be associated with mortality. We conducted a retrospective cohort study of first kidney allograft recipients between 1990 and 2008 represented in the Austrian Transplant Registry. We included 1441 patients of whom 683 received ESAs at any time after transplantation. Cox regression with cubic splines and linear estimates and the purposeful selection algorithm of covariables were used. The measure of variability was the moving standard deviation computed at three monthly intervals for the entire graft life. The hazard ratio (HR) of mortality and graft loss in the spline models increased with hemoglobin variability. The linear HR for mortality was 2.35 (95% confidence interval 1.75–3.17, P < 0.001) and functional graft loss 2.45 (1.76–3.40, P < 0.001). In an adjusted Cox model (ESA use, hemoglobin, age, diabetes, days on dialysis, eGFR, biopsy confirmed acute rejection and year of transplantation), hemoglobin variability was associated with mortality (HR: 2.11; 1.51–2.94; P < 0.001). No association with functional graft loss could be detected (HR: 1.34; 0.93-1.93; P = 0.121). These findings suggest that hemoglobin variability is associated with mortality of renal allograft recipients. PMID:22313094

  1. COPPER AND COBALT RELATED HEMOGLOBIN PRODUCTION IN EXPERIMENTAL ANEMIA

    PubMed Central

    Robscheit-Robbins, F. S.; Whipple, G. H.

    1942-01-01

    Copper added to a standard diet often effects a moderate increase in hemoglobin production in anemia due to blood loss. The copper response is quite irregular in contrast to the iron response. In these dogs there is no lack of copper held in reserve stores (liver and spleen) so the reaction is not related to an actual deficiency of the element. An effect upon enzyme complexes related to globin and hemoglobin production is to be considered. Cobalt under similar conditions causes no stimulus to hemoglobin production, rather an inhibitory effect when more than minimal doses are given. The claim that cobalt causes a polycythemia in dogs receives no support from our experiments. PMID:19871199

  2. Hemoglobin - a novel ligand of hepatocyte ectopic F1-ATPase.

    PubMed

    Gburek, J; Konopska, B; Juszczynska, K; Piwowar, A; Dziegiel, P; Borska, S; Tolosano, E; Golab, K

    2015-12-01

    The liver is largely responsible for free hemoglobin uptake, but the molecular mechanism of this phenomenon has never been revealed. This paper presents the results of the study on hemoglobin binding components of the hepatocyte membrane that were purified using affinity chromatography on a hemoglobin matrix and identified by peptide mass fingerprinting. Both F1-ATPase alpha and beta subunits were retrieved. The binding was confirmed via an intrinsic fluorescence quenching study using a purified recombinant F1-ATPase beta subunit, and the dissociation constant for the complex was estimated from the saturation binding curve (Kd = 7.5 x 10(-7) M). The results indicate that haemoglobin binds to hepatocyte ectopic F1-ATPase. We suggested the plausible role of the receptor in endocytosis of haemoglobin by the hepatocyte.

  3. Conformational changes monitored by fluorescence study on reconstituted hemoglobins

    NASA Astrophysics Data System (ADS)

    Venkateshrao, S.; Manoharan, P. T.

    2004-09-01

    Intrinsic steady state fluorescence measurements were performed on a series of reconstituted metal ion and hybrid hemoglobins (Hbs). At 296 nm excitation, the spectrum exhibits a broad and asymmetric feature in the case of copper and nickel reconstituted hemoglobins. Deconvolution of the fluorescence bands clearly reveals the existence of two definite peaks. A similar trend was also observed for hybrid hemoglobins (CuNi, NiCu, CuFe-CO, and NiFe-CO). A guassian fit of the fluorescence bands in these proteins again yields two prominent peaks, which are assigned as due to two different tryptophan (Trp) environments. A relative ratio of the amplitudes of these peaks indicates the percentage of T-character in these molecules. This is in support to our previous findings by other spectroscopic studies on the same molecules. These studies therefore, suggest the presence of two different environments of a tryptophan thereby revealing structural heterogeneity among the subunits.

  4. Erythrocyte phosphates and hemoglobin function in monotremes and some marsupials.

    PubMed

    Isaacks, R; Nicol, S; Sallis, J; Zeidler, R; Kim, H D

    1984-02-01

    Hematologic values, red blood cell (RBC) organic phosphate composition, hemoglobin function, and hemoglobin composition have been determined on blood from the monotremes, the duckbill platypus and the echidna, and three species of marsupials, the Tasmanian devil, the wallaby, and the brush-tail possum. Blood from the platypus had a RBC count of 8.63 X 10(6)/mm3, a mean corpuscular volume of 49.1 millemicron3, and a white blood cell count of 26.0 X 10(3)/mm3. The RBCs from the monotremes and the three marsupials exhibited hemoglobin polymorphism, each with three hemoglobin components. Addition of ATP, 2,3-bisphosphoglycerate (2,3-P2-glycerate), or inositol pentakisphosphate (inositol-P5) to phosphate-free hemoglobin from each species decreased hemoglobin oxygen affinity; the order of effect of these compounds was ATP less than 2,3-P2-glycerate less than inositol-P5. The RBCs of all species had concentrations of 2,3-P2-glycerate ranging from 6.02 mumol/ml RBCs in the wallaby to 10.39 mumol/ml RBCs in the possum. The RBCs from the three species of marsupials had concentrations of ATP ranging from 0.24 mumol/ml RBCs in the possum to 0.80 mumol/ml RBCs in the Tasmanian devil. The level of ATP in RBCs of the platypus and echidna were 0.06 and 0.03 mumol/ml RBCs, respectively.

  5. Independency of Fe ions in hemoglobin on immunomagnetic reduction assay

    NASA Astrophysics Data System (ADS)

    Yang, S. Y.; Lan, C. B.; Chen, C. H.; Horng, H. E.; Hong, Chin-Yih; Yang, H. C.; Lai, Y. K.; Lin, Y. H.; Teng, K. S.

    2009-10-01

    Immunomagnetic reduction (IMR), which involves measuring the reduction in the ac magnetic susceptibility of magnetic reagents, is due to the association between bio-functionalized magnetic nanoparticles and target bio-molecules. This has been demonstrated for assaying proteins in solutions free of Fe ions, such as serum. In this work, the validity of IMR assay for samples rich in Fe ions like hemoglobin (Hb) is investigated. According to the results, there is no magnetic signal contributed by Fe-ion-rich Hb. Furthermore, the results show a high sensitivity in assaying hemoglobin A1c (HbA1c) by using IMR.

  6. Structural significance of the amino terminal residues in human hemoglobin

    SciTech Connect

    Hefta, S.A.

    1986-01-01

    The amino terminal valine residues on the alpha chains of human hemoglobin are known to be important for the function of the molecule. Allosteric effectors such as protons, chloride ions and metabolic anions such as 2,3-diphosphoglycerate bind or associate with these residues and facilitate the release of oxygen. Carbon dioxide also functions as an effector as it is partly transported from the tissues to the lungs by binding to the amino terminal residues. This research describes the semisynthetic alteration of this region and the hemoglobin analogs produced were analyzed by /sup 13/C NMR.

  7. [Hemoglobins, XLVIII: the primary structure of hemoglobin of the Indian elephant (Elephas maximus, Proboscidea): beta 2 = Asn].

    PubMed

    Braunitzer, G; Jelkmann, W; Stangl, A; Schrank, B; Krombach, C

    1982-07-01

    The primary structure of the hemoglobin of the Indian Elephant (Elephas maximus) is given. The sequence was determined automatically in a sequenator. By homologous comparison with adult human HbA, the alpha-chains differ by 24 exchanges and the beta-chains by 27 exchanges. Furthermore, we report p(O2)50 values with regard to altered contact sites with 2,3-bisphosphoglycerate in Indian elephant hemoglobin. Our findings explain the low p(O2)50 and the reduced interaction with 2,3-bisphosphoglycerate. Elephant hemoglobin has, like that of the Llama, only five phosphate binding sites. In addition, we have made an attempt to relate these results to aspects of respiratory physiology. Some implications of these biochemical and physiological results, concerning the Second Punic War and Hannibal's Alp transition, are given.

  8. A recombinant human hemoglobin with anti-sickling properties greater than fetal hemoglobin.

    PubMed

    Levasseur, Dana N; Ryan, Thomas M; Reilly, Michael P; McCune, Steven L; Asakura, Toshio; Townes, Tim M

    2004-06-25

    A new recombinant, human anti-sickling beta-globin polypeptide designated beta(AS3) (betaGly(16) --> Asp/betaGlu(22) --> Ala/betaThr(87) --> Gln) was designed to increase affinity for alpha-globin. The amino acid substitutions at beta22 and beta87 are located at axial and lateral contacts of the sickle hemoglobin (HbS) polymers and strongly inhibit deoxy-HbS polymerization. The beta16 substitution confers the recombinant beta-globin subunit (beta(AS3)) with a competitive advantage over beta(S) for interaction with the alpha-globin polypeptide. Transgenic mouse lines that synthesize high levels of HbAS3 (alpha(2)beta(AS3)(2)) were established, and recombinant HbAS3 was purified from hemolysates and then characterized. HbAS3 binds oxygen cooperatively and has an oxygen affinity that is comparable with fetal hemoglobin. Delay time experiments demonstrate that HbAS3 is a potent inhibitor of HbS polymerization. Subunit competition studies confirm that beta(AS3) has a distinct advantage over beta(S) for dimerization with alpha-globin. When equal amounts of beta(S)- and beta(AS3)-globin monomers compete for limiting alpha-globin chains up to 82% of the tetramers formed is HbAS3. Knock-out transgenic mice that express exclusively human HbAS3 were produced. When these mice were bred with knock-out transgenic sickle mice the beta(AS3) polypeptides corrected all hematological parameters and organ pathology associated with the disease. Expression of beta(AS3)-globin should effectively lower the concentration of HbS in erythrocytes of patients with sickle cell disease, especially in the 30% percent of these individuals who coinherit alpha-thalassemia. Therefore, constructs expressing the beta(AS3)-globin gene may be suitable for future clinical trials for sickle cell disease. PMID:15084588

  9. Hemoglobin Birmingham and hemoglobin Galicia: two unstable beta chain variants characterized by small deletions and insertions.

    PubMed

    Wilson, J B; Webber, B B; Hu, H; Kutlar, A; Kutlar, F; Codrington, J F; Prchal, J T; Hall, K M; de Pablos, J M; Rodriguez, I

    1990-05-01

    Two unstable hemoglobins (Hbs) causing rather severe hemolytic anemia have been characterized. The beta chain of Hb Birmingham, found in an adult black man, is characterized by the loss of -Leu-Ala-His-Lys- at positions 141, 142, 143, and 144 and their replacement by one Gln residue. These changes are the result of a deletion of nine nucleotides, namely two base pairs (bp) of codon 141, all of codons 142 and 143, and one bp of codon 144; the remaining CAG triplet (C from codon 141 and AG from codon 144) codes for the inserted glutamine. In the beta chain of Hb Galicia from a Spanish patient, His and Val at positions 97 and 98 are replaced by one Leu residue. This is due to an ACG deletion in codons 97 and 98, which causes the removal of one His and one Val residue, while the remaining CTG triplet (C from codon 97 and TG from codon 98) codes for the inserted leucine residue. Two mechanisms, namely slipped mispairing in the presence of short repeats, and misreading by DNA polymerase due to a local distortion of the DNA helix, are considered in explaining the origin of the small deletions.

  10. 21 CFR 864.7415 - Abnormal hemoglobin assay.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Abnormal hemoglobin assay. 864.7415 Section 864.7415 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864.7415...

  11. 21 CFR 864.7440 - Electrophoretic hemoglobin analysis system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Electrophoretic hemoglobin analysis system. 864.7440 Section 864.7440 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages §...

  12. 21 CFR 864.5620 - Automated hemoglobin system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Automated hemoglobin system. 864.5620 Section 864.5620 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Automated and Semi-Automated Hematology Devices §...

  13. 21 CFR 864.5620 - Automated hemoglobin system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Automated hemoglobin system. 864.5620 Section 864.5620 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Automated and Semi-Automated Hematology Devices §...

  14. 21 CFR 864.7440 - Electrophoretic hemoglobin analysis system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Electrophoretic hemoglobin analysis system. 864.7440 Section 864.7440 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages §...

  15. 21 CFR 864.7415 - Abnormal hemoglobin assay.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Abnormal hemoglobin assay. 864.7415 Section 864.7415 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864.7415...

  16. 21 CFR 864.5620 - Automated hemoglobin system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Automated hemoglobin system. 864.5620 Section 864.5620 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Automated and Semi-Automated Hematology Devices §...

  17. 21 CFR 864.7440 - Electrophoretic hemoglobin analysis system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Electrophoretic hemoglobin analysis system. 864.7440 Section 864.7440 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages §...

  18. 21 CFR 864.7415 - Abnormal hemoglobin assay.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Abnormal hemoglobin assay. 864.7415 Section 864.7415 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864.7415...

  19. 21 CFR 864.7415 - Abnormal hemoglobin assay.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Abnormal hemoglobin assay. 864.7415 Section 864.7415 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864.7415...

  20. 21 CFR 864.7415 - Abnormal hemoglobin assay.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Abnormal hemoglobin assay. 864.7415 Section 864.7415 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864.7415...

  1. 21 CFR 864.5620 - Automated hemoglobin system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Automated hemoglobin system. 864.5620 Section 864.5620 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Automated and Semi-Automated Hematology Devices §...

  2. 21 CFR 864.7440 - Electrophoretic hemoglobin analysis system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Electrophoretic hemoglobin analysis system. 864.7440 Section 864.7440 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages §...

  3. 21 CFR 864.7440 - Electrophoretic hemoglobin analysis system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Electrophoretic hemoglobin analysis system. 864.7440 Section 864.7440 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages §...

  4. 21 CFR 864.5620 - Automated hemoglobin system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Automated hemoglobin system. 864.5620 Section 864.5620 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Automated and Semi-Automated Hematology Devices §...

  5. 21 CFR 864.7455 - Fetal hemoglobin assay.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Fetal hemoglobin assay. 864.7455 Section 864.7455 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864.7455 Fetal...

  6. Ultrasonic processing for recovery of chicken erythrocyte hemoglobin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hemoglobin from chicken blood has been shown to be a good substitute for synthetic polymeric flocculants. One stage of processing the blood entails breaking open the cells and releasing the cytoplasmic contents; in the present study, we investigate the use of ultrasonic processing at this stage. Was...

  7. Rapid and sensitive quantitation of heme in hemoglobinized cells.

    PubMed

    Marcero, Jason R; Piel Iii, Robert B; Burch, Joseph S; Dailey, Harry A

    2016-01-01

    Rapid and accurate heme quantitation in the research lab has become more desirable as the crucial role that intracellular hemoproteins play in metabolism continues to emerge. Here, the time-honored approaches of pyridine hemochromogen and fluorescence heme assays are compared with direct absorbance-based technologies using the CLARiTY spectrophotometer. All samples tested with these methods were rich in hemoglobin-associated heme, including buffered hemoglobin standards, whole blood from mice, and murine erythroleukemia (MEL) and K562 cells. While the pyridine hemochromogen assay demonstrated the greatest linear range of heme detection, all 3 methods demonstrated similar analytical sensitivities and normalized limits of quantitation of ∼1 µM. Surprisingly, the fluorescence assay was only shown to be distinct in its ability to quantitate extremely small samples. Using the CLARiTY system in combination with pyridine hemochromogen and cell count data, a common hemoglobin extinction coefficient for blood and differentiating MEL and K562 cells of 0.46 µM-1 cm-1 was derived. This value was applied to supplemental experiments designed to measure MEL cell hemoglobinization in response to the addition or removal of factors previously shown to affect heme biosynthesis (e.g., L-glutamine, iron). PMID:27528073

  8. Human macrophage hemoglobin-iron metabolism in vitro

    SciTech Connect

    Custer, G.; Balcerzak, S.; Rinehart, J.

    1982-01-01

    An entirely in vitro technique was employed to characterize hemoglobin-iron metabolism by human macrophages obtained by culture of blood monocytes and pulmonary alveolar macrophages. Macrophages phagocytized about three times as many erythrocytes as monocytes and six times as many erythrocytes as pulmonary alveolar macrophages. The rate of subsequent release of /sup 59/Fe to the extracellular transferrin pool was two- to fourfold greater for macrophages as compared to the other two cell types. The kinetics of /sup 59/Fe-transferrin release were characterized by a relatively rapid early phase (hours 1-4) followed by a slow phase (hours 4-72) for all three cell types. Intracellular movement of iron was characterized by a rapid shift from hemoglobin to ferritin that was complete with the onset of the slow phase of extracellular release. A transient increase in /sup 59/Fe associated with an intracellular protein eluting with transferrin was also observed within 1 hour after phagocytosis. The process of hemoglobin-iron release to extracellular transferrin was inhibited at 4 degrees C but was unaffected by inhibitory of protein synthesis, glycolysis, microtubule function, and microfilament function. These data emphasize the rapidity of macrophage hemoglobin iron metabolism, provide a model for characterization of this process in vitro, and in general confirm data obtained utilizing in vivo animal models.

  9. Effect of Some High Consumption Spices on Hemoglobin Glycation

    PubMed Central

    Naderi, G. H.; Dinani, Narges J.; Asgary, S.; Taher, M.; Nikkhoo, N.; Boshtam, M.

    2014-01-01

    Formation of glycation products is major factor responsible in complications of diabetes. Worldwide trend is toward the use of natural additives in reducing the complications of diseases. Therefore, there is a growing interest in natural antiglycation found in plants. Herbs and spices are one of the most important targets to search for natural antiglycation from the point of view of safety. This study investigated the ability of some of the spices to inhibit glycation process in a hemoglobin/glucose model system and compared their potency with each other. For this subject the best concentration and time to incubate glucose with hemoglobin was investigated. Then the glycosylation degree of hemoglobin in the presence of extracts by the three concentrations 0.25, 0.5 and 1 μg/ml was measured colorimetrically at 520 nm. Results represent that some of extracts such as wild caraway, turmeric, cardamom and black pepper have inhibitory effects on hemoglobin glycation. But some of the extracts such as anise and saffron have not only inhibitory effects but also aggravated this event and have proglycation properties. In accordance with the results obtained we can conclude that wild caraway, turmeric, cardamom and black pepper especially wild caraway extracts are potent antiglycation agents, which can be of great value in the preventive glycation-associated complications in diabetes. PMID:25593391

  10. 21 CFR 522.1125 - Hemoglobin glutamer-200 (bovine).

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...) Indications for use. For the treatment of anemia in dogs by increasing systemic oxygen content (plasma hemoglobin concentration) and improving the clinical signs associated with anemia, regardless of the cause of anemia (hemolysis, blood loss, or ineffective erythropoiesis). (3) Limitations. For intravenous use...

  11. 21 CFR 522.1125 - Hemoglobin glutamer-200 (bovine).

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...) Indications for use. For the treatment of anemia in dogs by increasing systemic oxygen content (plasma hemoglobin concentration) and improving the clinical signs associated with anemia, regardless of the cause of anemia (hemolysis, blood loss, or ineffective erythropoiesis). (3) Limitations. For intravenous use...

  12. Effect of some high consumption spices on hemoglobin glycation.

    PubMed

    Naderi, G H; Dinani, Narges J; Asgary, S; Taher, M; Nikkhoo, N; Boshtam, M

    2014-01-01

    Formation of glycation products is major factor responsible in complications of diabetes. Worldwide trend is toward the use of natural additives in reducing the complications of diseases. Therefore, there is a growing interest in natural antiglycation found in plants. Herbs and spices are one of the most important targets to search for natural antiglycation from the point of view of safety. This study investigated the ability of some of the spices to inhibit glycation process in a hemoglobin/glucose model system and compared their potency with each other. For this subject the best concentration and time to incubate glucose with hemoglobin was investigated. Then the glycosylation degree of hemoglobin in the presence of extracts by the three concentrations 0.25, 0.5 and 1 μg/ml was measured colorimetrically at 520 nm. Results represent that some of extracts such as wild caraway, turmeric, cardamom and black pepper have inhibitory effects on hemoglobin glycation. But some of the extracts such as anise and saffron have not only inhibitory effects but also aggravated this event and have proglycation properties. In accordance with the results obtained we can conclude that wild caraway, turmeric, cardamom and black pepper especially wild caraway extracts are potent antiglycation agents, which can be of great value in the preventive glycation-associated complications in diabetes.

  13. Correlations between oxygen affinity and sequence classifications of plant hemoglobins

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plants express three phylogenetic classes of hemoglobins (Hb) based on sequence analyses. Class 1 and 2 Hbs are full length globins with the classical 8 helix Mb-like fold, whereas Class 3 plant Hbs resemble the truncated globins found in bacteria. With the exception of the specialized leghemoglobin...

  14. Occult hemoglobin as an indicator of impingement stress in fishes

    SciTech Connect

    Not Available

    1980-01-01

    During the process of impingement on cooling system intake screens, fish may be subject to different types of stress, the total of which often results in the death of individual fish. This report assesses the use of occult hemoglobin in fish demand mucus as an indicator of impingement stress. (ACR)

  15. Using a Poetry Reading on Hemoglobin to Enhance Subject Matter

    ERIC Educational Resources Information Center

    Herrick, Richard S.; Cording, Robert K.

    2013-01-01

    student interest in the beauty and mystery of chemistry. A reading of the poem "Jerry-Built Forever" (on various aspects of hemoglobin) is used as an example; the poem is included in the article. Details of how the reading was performed and reactions of the…

  16. Influence of hemoglobin on non-invasive optical bilirubin sensing

    NASA Astrophysics Data System (ADS)

    Jiang, Jingying; Gong, Qiliang; Zou, Da; Xu, Kexin

    2012-03-01

    Since the abnormal metabolism of bilirubin could lead to diseases in the human body, especially the jaundice which is harmful to neonates. Traditional invasive measurements are difficult to be accepted by people because of pain and infection. Therefore, the real-time and non-invasive measurement of bilirubin is of great significance. However, the accuracy of currently transcutaneous bilirubinometry(TcB) is generally not high enough, and affected by many factors in the human skin, mostly by hemoglobin. In this talk, absorption spectra of hemoglobin and bilirubin have been collected and analyzed, then the Partial Least Squares (PLS) models have been built. By analyzing and comparing the Correlation and Root Mean Square Error of Prediction(RMSEP), the results show that the Correlation of bilirubin solution model is larger than that of the mixture solution added with hemoglobin, and its RMSEP value is smaller than that of mixture solution. Therefore, hemoglobin has influences on the non-invasive optical bilirubin sensing. In next step, it is necessary to investigate how to eliminate the influence.

  17. The Relationship Between Hemoglobin Level and Intellectual Function.

    ERIC Educational Resources Information Center

    Munro, Nancy

    In a study to learn whether or not poor nutrition, as indicated by low hemoglobin levels, affects intelligence and behavior, 113 Head Start children in Missoula, Montana took part. Group testing with the Lorge Thorndike Intelligence Test and individual testing with the Wechsler and Primary Scale of Intelligence or Wechsler Intelligence Scale for…

  18. Effect of some high consumption spices on hemoglobin glycation.

    PubMed

    Naderi, G H; Dinani, Narges J; Asgary, S; Taher, M; Nikkhoo, N; Boshtam, M

    2014-01-01

    Formation of glycation products is major factor responsible in complications of diabetes. Worldwide trend is toward the use of natural additives in reducing the complications of diseases. Therefore, there is a growing interest in natural antiglycation found in plants. Herbs and spices are one of the most important targets to search for natural antiglycation from the point of view of safety. This study investigated the ability of some of the spices to inhibit glycation process in a hemoglobin/glucose model system and compared their potency with each other. For this subject the best concentration and time to incubate glucose with hemoglobin was investigated. Then the glycosylation degree of hemoglobin in the presence of extracts by the three concentrations 0.25, 0.5 and 1 μg/ml was measured colorimetrically at 520 nm. Results represent that some of extracts such as wild caraway, turmeric, cardamom and black pepper have inhibitory effects on hemoglobin glycation. But some of the extracts such as anise and saffron have not only inhibitory effects but also aggravated this event and have proglycation properties. In accordance with the results obtained we can conclude that wild caraway, turmeric, cardamom and black pepper especially wild caraway extracts are potent antiglycation agents, which can be of great value in the preventive glycation-associated complications in diabetes. PMID:25593391

  19. 21 CFR 864.7400 - Hemoglobin A2 assay.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Hemoglobin A2 assay. 864.7400 Section 864.7400 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... polypeptide chains). (b) Classification. Class II (performance standards)....

  20. 21 CFR 864.7400 - Hemoglobin A 2 assay.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Hemoglobin A 2 assay. 864.7400 Section 864.7400 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... polypeptide chains). (b) Classification. Class II (performance standards)....

  1. 21 CFR 864.7400 - Hemoglobin A2 assay.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Hemoglobin A2 assay. 864.7400 Section 864.7400 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... polypeptide chains). (b) Classification. Class II (performance standards)....

  2. 21 CFR 864.7400 - Hemoglobin A2 assay.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Hemoglobin A2 assay. 864.7400 Section 864.7400 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... polypeptide chains). (b) Classification. Class II (performance standards)....

  3. 21 CFR 864.7400 - Hemoglobin A 2 assay.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Hemoglobin A 2 assay. 864.7400 Section 864.7400 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... polypeptide chains). (b) Classification. Class II (performance standards)....

  4. 21 CFR 866.5470 - Hemoglobin immunological test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Hemoglobin immunological test system. 866.5470 Section 866.5470 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunological Test Systems §...

  5. 21 CFR 866.5470 - Hemoglobin immunological test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Hemoglobin immunological test system. 866.5470 Section 866.5470 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunological Test Systems §...

  6. Hemoglobin, Growth, and Attention of Infants in Southern Ethiopia

    ERIC Educational Resources Information Center

    Aubuchon-Endsley, Nicki L.; Grant, Stephanie L.; Berhanu, Getenesh; Thomas, David G.; Schrader, Sarah E.; Eldridge, Devon; Kennedy, Tay; Hambidge, Michael

    2011-01-01

    Male and female infants from rural Ethiopia were tested to investigate relations among hemoglobin (Hb), anthropometry, and attention. A longitudinal design was used to examine differences in attention performance from 6 (M = 24.9 weeks, n = 89) to 9 months of age (M = 40.6 weeks, n = 85), differences hypothesized to be related to changes in iron…

  7. Liposome-encapsulated hemoglobin: an oxygen-carrying fluid.

    PubMed

    Rabinovici, R; Rudolph, A S; Ligler, F S; Yue, T L; Feuerstein, G

    1990-09-01

    From the original concept of encapsulating hemoglobin in an inert shell, LEH has evolved into a fluid proven to carry oxygen, capable of surviving for reasonable periods in the circulation, and amenable to large-scale production. The formula for the outer shell evolved from synthetic, nonlipid materials, to egg-lecithin-based lipid mixtures, to distearoyl-phosphatidylcholine-based blends. The fabrication technology started with the production of milliliter quantities and methods detrimental to the hemoglobin and developed into high-pressure extrusion systems producing multi-liter quantities without damaging the hemoglobin. The development of methods for analysis and quality control of LEH has been difficult: even techniques for measuring basic characteristics of size and methemoglobin are still being standardized. In vivo studies have established that LEH has a circulation half-life of 16-20 hr and can carry oxygen sufficient to sustain life, but safety has yet to be proven. In each of the general areas mentioned above, there are opportunities for further improvement and characterization. The source of the hemoglobin and the coencapsulation of hemoglobin modifiers needs to be reassessed now that human hemoglobin has been cloned and functional hemoglobin can be produced by using fermentation techniques. The development of routine methods for quality control and assurance must accompany the production of large quantities of LEH for preclinical studies. Whether or not the LEH can and should be manufactured as a lyophilized product must be assessed. Animal studies must done to prove safety as well as efficacy in a variety of clinical models, including hemorrhagic and septic shock as well as various levels of isovolemic exchange. One approach toward the improvement of the LEH is to alter the liposome surface to increase its biocompatibility. The evolution of biocompatible liposome surfaces has included carbohydrate moieties, as carbohydrates are expressed on the

  8. Plant hemoglobins: a molecular fossil record for the evolution of oxygen transport.

    PubMed

    Hoy, Julie A; Robinson, Howard; Trent, James T; Kakar, Smita; Smagghe, Benoit J; Hargrove, Mark S

    2007-08-01

    The evolution of oxygen transport hemoglobins occurred on at least two independent occasions. The earliest event led to myoglobin and red blood cell hemoglobin in animals. In plants, oxygen transport "leghemoglobins" evolved much more recently. In both events, pentacoordinate heme sites capable of inert oxygen transfer evolved from hexacoordinate hemoglobins that have unrelated functions. High sequence homology between hexacoordinate and pentacoordinate hemoglobins in plants has poised them for potential structural analysis leading to a molecular understanding of this important evolutionary event. However, the lack of a plant hexacoordinate hemoglobin structure in the exogenously ligand-bound form has prevented such comparison. Here we report the crystal structure of the cyanide-bound hexacoordinate hemoglobin from barley. This presents the first opportunity to examine conformational changes in plant hexacoordinate hemoglobins upon exogenous ligand binding, and reveals structural mechanisms for stabilizing the high-energy pentacoordinate heme conformation critical to the evolution of reversible oxygen binding hemoglobins.

  9. Plant Hemoglobins: A Molecular Fossil Record for the Evolutin of Oxygen Transport

    SciTech Connect

    Hoy,J.; Robinson, H.; Trent, lll, J.; Kakar, S.; Smagghe, B.; Hargrove, M.

    2007-01-01

    The evolution of oxygen transport hemoglobins occurred on at least two independent occasions. The earliest event led to myoglobin and red blood cell hemoglobin in animals. In plants, oxygen transport 'leghemoglobins' evolved much more recently. In both events, pentacoordinate heme sites capable of inert oxygen transfer evolved from hexacoordinate hemoglobins that have unrelated functions. High sequence homology between hexacoordinate and pentacoordinate hemoglobins in plants has poised them for potential structural analysis leading to a molecular understanding of this important evolutionary event. However, the lack of a plant hexacoordinate hemoglobin structure in the exogenously ligand-bound form has prevented such comparison. Here we report the crystal structure of the cyanide-bound hexacoordinate hemoglobin from barley. This presents the first opportunity to examine conformational changes in plant hexacoordinate hemoglobins upon exogenous ligand binding, and reveals structural mechanisms for stabilizing the high-energy pentacoordinate heme conformation critical to the evolution of reversible oxygen binding hemoglobins.

  10. Purification of diverse hemoglobins by metal salt precipitation.

    PubMed

    Zimmerman, Devon; Dienes, Jack; Abdulmalik, Osheiza; Elmer, Jacob J

    2016-09-01

    Although donated blood is the preferred material for transfusion, its limited availability and stringent storage requirements have motivated the development of blood substitutes. The giant extracellular hemoglobin (aka erythrocruorin) of the earthworm Lumbricus terrestris (LtEc) has shown promise as a blood substitute, but an efficient purification method for LtEc must be developed to meet the potential large demand for blood substitutes. In this work, an optimized purification process that uses divalent and trivalent metal salts to selectively precipitate human, earthworm, and bloodworm hemoglobin (HbA, LtEc, and GdHb, respectively) from crude solutions was developed. Although several metal ions were able to selectively precipitate LtEc, Zn(2+) and Ni(2+) provided the lowest heme oxidation and highest overall yield of LtEc. In contrast, Zn(2+) was the only metal ion that completely precipitated HbA and GdHb. Polyacrylamide gel electrophoresis (PAGE) analysis shows that metal precipitation removes several impurities to provide highly pure hemoglobin samples. Heme oxidation levels were relatively low for Zn(2+)-purified HbA and LtEc (2.4±1.3% and 5.3±2.1%, respectively), but slightly higher for Ni(2+)-purified LtEc (8.4±1.2%). The oxygen affinity and cooperativity of the precipitated samples are also identical to samples purified with tangential flow filtration (TFF) alone, indicating the metal precipitation does not significantly affect the function of the hemoglobins. Overall, these results show that hemoglobins from several different species can be highly purified using a combination of metal (Zn(2+)) precipitation and tangential flow filtration. PMID:26363116

  11. Purification of diverse hemoglobins by metal salt precipitation.

    PubMed

    Zimmerman, Devon; Dienes, Jack; Abdulmalik, Osheiza; Elmer, Jacob J

    2016-09-01

    Although donated blood is the preferred material for transfusion, its limited availability and stringent storage requirements have motivated the development of blood substitutes. The giant extracellular hemoglobin (aka erythrocruorin) of the earthworm Lumbricus terrestris (LtEc) has shown promise as a blood substitute, but an efficient purification method for LtEc must be developed to meet the potential large demand for blood substitutes. In this work, an optimized purification process that uses divalent and trivalent metal salts to selectively precipitate human, earthworm, and bloodworm hemoglobin (HbA, LtEc, and GdHb, respectively) from crude solutions was developed. Although several metal ions were able to selectively precipitate LtEc, Zn(2+) and Ni(2+) provided the lowest heme oxidation and highest overall yield of LtEc. In contrast, Zn(2+) was the only metal ion that completely precipitated HbA and GdHb. Polyacrylamide gel electrophoresis (PAGE) analysis shows that metal precipitation removes several impurities to provide highly pure hemoglobin samples. Heme oxidation levels were relatively low for Zn(2+)-purified HbA and LtEc (2.4±1.3% and 5.3±2.1%, respectively), but slightly higher for Ni(2+)-purified LtEc (8.4±1.2%). The oxygen affinity and cooperativity of the precipitated samples are also identical to samples purified with tangential flow filtration (TFF) alone, indicating the metal precipitation does not significantly affect the function of the hemoglobins. Overall, these results show that hemoglobins from several different species can be highly purified using a combination of metal (Zn(2+)) precipitation and tangential flow filtration.

  12. Manipulation of hemoglobin expression affects Arabidopsis shoot organogenesis.

    PubMed

    Wang, Yaping; Elhiti, Mohamed; Hebelstrup, Kim H; Hill, Robert D; Stasolla, Claudio

    2011-10-01

    Over the past few years non-symbiotic plant hemoglobins have been described in a variety of plant species where they fulfill several functions ranging from detoxification processes to basic aspects of plant growth and post-embryonic development. To date no information is available on the role of hemoglobins during in vitro morphogenesis. Shoot organogenesis was induced in Arabidopsis lines constitutively expressing class 1, 2 and 3 hemoglobins (GLB1, 2 and 3) and lines in which the respective genes were either downregulated by RNAi (GLB1) or knocked out (GLB2 and GLB3). The process was executed by culturing root explants on an initial auxin-rich callus induction medium (CIM) followed by a transfer onto a cytokinin-containing shoot induction medium (SIM). While the repression of GLB2 inhibited organogenesis the over-expression of GLB1 or GLB2 enhanced the number of shoots produced in culture, and altered the transcript levels of genes participating in cytokinin perception and signalling. The up-regulation of GLB1 or GLB2 activated CKI1 and AHK3, genes encoding cytokinin receptors and affected the transcript levels of cytokinin responsive regulators (ARRs). The expression of Type-A ARRs (ARR4, 5, 7, 15, and 16), feed-back repressors of the cytokinin pathway, was repressed in both hemoglobin over-expressors whereas that of several Type-B ARRs (ARR2, 12, and 13), transcription activators of cytokinin-responsive genes, was induced. Such changes enhanced the sensitivity of the root explants to cytokinin allowing the 35S::GLB1 and 35S::GLB2 lines to produce shoots at low cytokinin concentrations which did not promote organogenesis in the WT line. These results show that manipulation of hemoglobin can modify shoot organogenesis in Arabidopsis and possibly in those systems partially or completely unresponsive to applications of exogenous cytokinins. PMID:21741261

  13. Near-infrared absorbance measurements of hemoglobin solutions incubated with glucose

    NASA Astrophysics Data System (ADS)

    Zhernovaya, Olga S.; Tuchin, Valery V.; Meglinski, Igor; Ritchie, Laurie

    2007-02-01

    It is known that glucose influences on spectral properties of blood and hemoglobin and interacts with plasma proteins and hemoglobin in erythrocytes. Changes of optical properties of blood and hemoglobin at glucose concentration within physiological level are important for diagnosis and monitoring of diabetes. The purpose of this study is to investigate the effect of presence of glucose and glycation of hemoglobin on absorbance of aqueous hemoglobin solutions with different glucose concentrations. Measurements were taken using spectrophotometer EQUINOX 55 (Bruker Optic GmbH) in a range 1000-1800 nm. Water has absorption bands in the near-infrared region which may be influenced by glucose presence. We have hypothesized that glucose and hemoglobin, especially glycated hemoglobin, may influence the absorption band of water in solution. The hemoglobin solutions with different amount of glucose (from 0 to 1000 mg/dl with a step 100 mg/dl) were incubated up to 28 days. Our measurements show that presence of glucose affects the spectra of aqueous hemoglobin solutions. The magnitude of absorbance depends on glucose concentration. At the beginning of incubation hemoglobin solution without glucose has the lowest absorbance magnitude, but after a rather long time of incubation (28 days) the absorbance of hemoglobin solutions with glucose become smaller compared to the absorbance of hemoglobin solution without glucose. This fact may be explained by assumption of hemoglobin glycation, when glucose molecules chemically bind to hemoglobin, and water binding to hemoglobin. In the case of water binding to hemoglobin molecules the amount of free water molecules in solution decreases, so the water aborbance is excepted to decrease.

  14. Identification of chloride-binding sites in hemoglobin by nuclear-magnetic-resonance quadrupole-relaxation studies of hemoglobin digests.

    PubMed

    Chiancone, E; Norne, J E; Forsén, S; Bonaventura, J; Brunori, M; Antonini, E; Wyman, J

    1975-07-01

    35Cl minus-nuclear magnetic resonance (NMR) studies indicate that various digests of human hemoglobin with carboxypeptidase A and B, or a combination of the two, may be used for the identification of chloride binding sites. All the digestion products contain, like hemoglobin itself, at least two classes of binding sites, one of high, the others of low affinity. The pH dependence of the excess linewidth of the 35Cl minus NMR signal indicates that in the simple digests with either carboxypeptidase A or B, chloride is bound with high affinity at or near His-beta146-Asp-beta94 and at or near Val-alpha1-Arg-alpha141. The high-affinity sites show, in the case of the simple digests, a strong oxygen linkage which is lost in the forms digested with both carboxypeptidase A and B; this linkage may thus be correlated to the presence of conformational changes. Organic phosphates, like inositol hexaphosphate, show competition for some of the high-affinity chloride binding sites in hemoglobin and in the simple digests. This competition is likewise lost in the doubly digested hemoglobins. PMID:236

  15. Phase characterization of oscillatory components of the cerebral concentrations of oxy-hemoglobin and deoxy-hemoglobin

    NASA Astrophysics Data System (ADS)

    Pierro, Michele; Sassaroli, Angelo; Zheng, Feng; Fantini, Sergio

    2011-02-01

    We present a study of the relative phase of oscillations of cerebral oxy- and deoxy-hemoglobin concentrations in the low-frequency range, namely 0.04-0.12 Hz. We have characterized the potential contributions of noise to the measured phase distributions, and we have performed phase measurements on the brain of a human subject at rest, and on the brain of a human subject during stage I sleep. While phase distributions of pseudo hemodynamic oscillations generated from noise (obtained by applying to two independent sets of random numbers the same linear transformation that converts absorption coefficients at 690 and 830 nm into concentrations of oxy- and deoxy-hemoglobin) are peaked at 180º, those associated with real hemodynamic changes can be peaked around any value depending on the underlying physiology and hemodynamics. In particular, preliminary results reported here indicate a greater phase lead of deoxy-hemoglobin vs. oxy-hemoglobin low-frequency oscillations during stage I sleep (82º +/- 55º) than while the subject is awake (19º +/- 58º).

  16. ESA frequency and hemoglobin levels in patients on peritoneal dialysis: 2002 vs. 2008.

    PubMed

    Kruger, Ann; Trowbridge, Lynette; York, Jane; Butcher, Belinda; Bradley, Jennifer

    2013-01-01

    This study examined whether a change infrequency of administration of erythropoietin-stimulating agent affected hemoglobin levels in patients on peritoneal dialysis. Data were extracted from the Australian Renal Anaemia Management database for the years 2002 and 2008. Less frequent dosing and increasing age were associated with higher hemoglobin levels, while increasing ferritin levels and later years were associated with lower hemoglobin levels.

  17. Comparable application of the OCT and Abbe refractometers for measurements of glycated hemoglobin portion in blood

    NASA Astrophysics Data System (ADS)

    Zhernovaya, Olga S.; Tuchin, Valery V.; Wang, Ruikang K.

    2006-02-01

    It is known that glucose interacts with plasma proteins and hemoglobin in erythrocytes. Glycated (glycosylated) hemoglobin is the result of an irreversible non-enzymatic fixation of glucose on the beta chain of hemoglobin A. The amount of glycated hemoglobin depends on blood glucose concentration and reflects the mean glycemia of about the previous 2-3 months. Glycated hemoglobin is a useful marker for long-term glucose control in diabetic patients. Therefore, the search of quick and high sensitive methods for measurement of glycated hemoglobin portion in blood is important. This study is focused on the determination of refractive index of hemoglobin solution at different glucose concentrations. Measurements were performed using Abbe refractometer at 589 nm and optical coherence tomography (OCT) at 820 nm. The different amount of glucose (from 0 to 1000 mg/dl with a step 100 mg/dl) was added to hemoglobin solution. Theoretical values of refractive index of hemoglobin solutions with glucose were calculated supposing non-interacting hemoglobin and glucose molecules. There is a difference between measured and calculated values of refractive index. This difference is due to glucose binding to hemoglobin. It is shown that the refractive index measurements can be applied for the evaluation of glycated hemoglobin amount.

  18. MR Imaging-derived Oxygen-Hemoglobin Dissociation Curves and Fetal-Placental Oxygen-Hemoglobin Affinities.

    PubMed

    Avni, Reut; Golani, Ofra; Akselrod-Ballin, Ayelet; Cohen, Yonni; Biton, Inbal; Garbow, Joel R; Neeman, Michal

    2016-07-01

    Purpose To generate magnetic resonance (MR) imaging-derived, oxygen-hemoglobin dissociation curves and to map fetal-placental oxygen-hemoglobin affinity in pregnant mice noninvasively by combining blood oxygen level-dependent (BOLD) T2* and oxygen-weighted T1 contrast mechanisms under different respiration challenges. Materials and Methods All procedures were approved by the Weizmann Institutional Animal Care and Use Committee. Pregnant mice were analyzed with MR imaging at 9.4 T on embryonic days 14.5 (eight dams and 58 fetuses; imprinting control region ICR strain) and 17.5 (21 dams and 158 fetuses) under respiration challenges ranging from hyperoxia to hypoxia (10 levels of oxygenation, 100%-10%; total imaging time, 100 minutes). A shorter protocol with normoxia to hyperoxia was also performed (five levels of oxygenation, 20%-100%; total imaging time, 60 minutes). Fast spin-echo anatomic images were obtained, followed by sequential acquisition of three-dimensional gradient-echo T2*- and T1-weighted images. Automated registration was applied to align regions of interest of the entire placenta, fetal liver, and maternal liver. Results were compared by using a two-tailed unpaired Student t test. R1 and R2* values were derived for each tissue. MR imaging-based oxygen-hemoglobin dissociation curves were constructed by nonlinear least square fitting of 1 minus the change in R2*divided by R2*at baseline as a function of R1 to a sigmoid-shaped curve. The apparent P50 (oxygen tension at which hemoglobin is 50% saturated) value was derived from the curves, calculated as the R1 scaled value (x) at which the change in R2* divided by R2*at baseline scaled (y) equals 0.5. Results The apparent P50 values were significantly lower in fetal liver than in maternal liver for both gestation stages (day 14.5: 21% ± 5 [P = .04] and day 17.5: 41% ± 7 [P < .0001]). The placenta showed a reduction of 18% ± 4 in mean apparent P50 values from day 14.5 to day 17.5 (P = .003

  19. [Hemoglobins, XLVII. Hemoglobins of the bar-headed goose (Anser indicus): primary structure and physiology of respiration, systematic and evolution].

    PubMed

    Oberthür, W; Braunitzer, G; Würdinger, I

    1982-06-01

    The primary structures of the alpha- and beta-chains of the main component of Bar-headed Goose (Anser indicus) are given. By homologous comparison with the hemoglobin of the Grey-Lag Goose (Anser anser) 3 differences were found in the alpha-chains, 1 difference in the beta-chains. In position alpha 119 H2Ala and beta 125 H3Asp alpha 1 beta 2-contact points are changed. The mutation alpha 63 E12Val brings a drastic change in tertiary structure of the alpha-chains of Bar-headed Goose: the helices E and B are moved apart by 1.5 A as there is no room for the larger side chain. This is probably the reason for a slightly higher intrinsic oxygen affinity of Bar-headed Goose hemoglobin. The bindings of inositol pentaphosphate on hemoglobin are identical in Grey-Lag Goose and Bar-headed Goose (contact points are not mutated). The reason for the increased difference in oxygen affinity by binding of inositol pentaphosphate is probably caused by two mutations in alpha 1 beta 2-contact points. It suggests that these two mutations are the reason for a different interaction between alpha- and beta-chains under the influence of inositol pentaphosphate by Grey-Lag and Bar-headed Goose hemoglobins. The difference in the primary structure of the Grey-Lag and Bar-headed Goose hemoglobins suggests that the Bar-headed Goose is not the genus of anser. Unfinished experiments (about 80% of the sequences) of White-fronted Goose (Anser albifrons a.) and Snow Goose (Anser caerulescens c.) show no exchanges with Grey-Lag Goose hemoglobin. The Canada Goose (Branta canadensis), however, which belongs to the genus Branta, has a number of substitutions similar to the Bar-headed Goose hemoglobin. These changes in primary structure suggest that Grey-Lag Goose and Bar-headed Goose are separated by a period of 9-15 Million years. This would support the hypothesis that the two species of goose became geographically separated by the elevation of the Himalayas. PMID:7106705

  20. Phenotypic expression of hemoglobins A₂, E and F in various hemoglobin E related disorders.

    PubMed

    Sae-ung, Nattaya; Srivorakun, Hataichanok; Fucharoen, Goonnapa; Yamsri, Supawadee; Sanchaisuriya, Kanokwan; Fucharoen, Supan

    2012-01-15

    Study on the phenotypic expression of hemoglobin (Hb) A(2) and Hb E in Hb E disorders has been difficult due to the co-separation of Hb A(2) and Hb E in most Hb analysis assays. Because these two Hbs are separated on capillary electrophoresis, we studied phenotypic expression of Hbs A(2), E and F in various Hb E disorders using this system. This was done on 362 subjects with several Hb E disorders including heterozygous Hb E, homozygous Hb E, β-thalassemia/Hb E, δβ-thalassemia/Hb E, and Hb Lepore/Hb E and those of these disorders with several forms of α-thalassemia. Normal controls showed Hb A(2) of 2.7 ± 0.3%. Heterozygous Hb E and homozygous Hb E had elevated Hb A(2) i.e. 3.8 ± 0.3% and 4.8 ± 0.5%, respectively. Further elevations were observed for β(0)-thalassemia/Hb E (6.1 ± 1.9%) and β(+)-thalassemia/Hb E (7.1 ± 1.2%). Interestingly, no elevation of Hb A(2) was found in the δβ-thalassemia/Hb E, and Hb Lepore/Hb E (2.3 ± 0.3%) but higher Hb F levels were noted which could be useful diagnostic markers. The levels of Hb E were variable. Co-inheritance of these Hb E disorders with α-thalassemia were associated with lower outputs of Hb E and Hb F but the levels of Hb A(2) were not altered. Different phenotypic expression of Hb A(2), Hb E and Hb F could help in differential diagnosis of these Hb E related disorders commonly encountered in the regions where access to molecular techniques is limited.

  1. Noninvasive investigation of skin local hypothermia influence upon local oxygenation and hemoglobin concentration

    NASA Astrophysics Data System (ADS)

    Douplik, Alexandre Y.; Kessler, Manfred D.; Kakihana, Yasuyuki; Krug, Alfons

    1997-08-01

    Functional evaluation of local hemoglobin concentration and hemoglobin oxygenation based on back scattering spectra from human skin in vivo have been obtained in visible range (502 - 628 nm) by a rapid microlightguide spectrometer (EMPHO II) with step 250 micrometer. Analysis of received results has shown that during local cooling there is two nearly simultaneous reactions: reduction of hemoglobin concentration and increase of hemoglobin oxygenation level. In a case when one has used previous heating of planning place for cooling, reduction of hemoglobin concentration is expressed higher by 22 - 33%.

  2. Concurrent measurement of cellular turbidity and hemoglobin to evaluate the antioxidant activity of plants.

    PubMed

    Bellik, Yuva; Iguer-Ouada, Mokrane

    2016-01-01

    In past decades, a multitude of analytical methods for measuring antioxidant activity of plant extracts has been developed. However, when using methods to determine hemoglobin released from human erythrocytes treated with ginger extracts, we found hemoglobin concentrations were significantly higher than in untreated control samples. This suggests in the presence of antioxidants that measuring hemoglobin alone is not sufficient to determine hemolysis. We show concurrent measurement of erythrocyte concentration and hemoglobin is essential in such assays, and describe a new protocol based on simultaneous measurement of cellular turbidity and hemoglobin.

  3. Virucidal levels of ozone induce hemolysis and hemoglobin degradation

    SciTech Connect

    Wagner, S.J.; Wagner, K.F.; Friedman, L.I.; Benade, L.F. )

    1991-10-01

    The animal virus, vesicular stomatitis virus (VSV), and the bacterial virus, phi 6, were inactivated by greater than 4 log10 in response to incubation with 13 to 14 mL of 1.4 mmol per L (65 micrograms/mL) to 1.6 mmol per L (75 micrograms/mL) of overlaid ozone in virus-spiked, dilute, red cell suspensions. Virus inactivation was greatly inhibited when ozone was overlaid in the presence of high-hematocrit red cells or, to a lesser degree, high levels of plasma. At hematocrits at which 5 to 6 log10 of VSV were inactivated, ozone caused 30-percent hemolysis, as measured by the loss of total cellular hemoglobin. Unexpectedly, this level of hemolysis could not be observed in supernatants because of the ozone-induced destruction (bleaching) of extracellular hemoglobin. These results suggest that ozone may have little biological specificity for damaging viruses over red cells.

  4. Vitreoscilla hemoglobin promotes Salecan production by Agrobacterium sp. ZX09*

    PubMed Central

    Chen, Yun-mei; Xu, Hai-yang; Wang, Yang; Zhang, Jian-fa; Wang, Shi-ming

    2014-01-01

    Salecan is a novel exopolysaccharide produced by the strain Agrobacterium sp. ZX09, and it is composed of only glucose monomers. The unique chemical composition and excellent physicochemical properties make Salecan a promising material for applications in coagulation, lubrication, protection against acute liver injury, and alleviating constipation. In this study, we cloned the Vitreoscilla hemoglobin gene into a broad-host-range plasmid pCM158. Without antibiotic selection, there was negligible loss of the plasmid in the host Agrobacterium sp. ZX09 after one passage of cultivation. The expression of Vitreoscilla hemoglobin was demonstrated by carbon monoxide (CO) difference spectrum. The engineered strain Agrobacterium sp. ZX09 increased Salecan yield by 30%. The other physiological changes included its elevated respiration rate and cellular invertase activity. PMID:25367790

  5. First Reported Case of Proliferative Retinopathy in Hemoglobin SE Disease

    PubMed Central

    Yang, Christopher; Fantin, Aldo; Darnley-Fisch, Deborah; Desai, Uday

    2014-01-01

    We report the first case of proliferative sickle cell retinopathy in a patient with hemoglobin SE (Hb SE) disease. Only a few dozen cases of Hb SE disease have been reported previously, and none had evidence of proliferative retinopathy. A 56-year-old African American man presented to our clinic for routine examination and was found to have sea-fan peripheral neovascularization bilaterally without maculopathy. Hemoglobin analysis revealed Hb SE heterozygosity. Sector laser photocoagulation to areas of nonperfusion in both eyes resulted in regression of the peripheral neovascularization over a period of 6 months. Although Hb SE disease is rare, the incidence of Hb SE disease is postulated to rise in the future. Awareness of its potential ocular complications is needed to appropriately refer these patients for screening. PMID:25210638

  6. Neonatal Cyanosis Due to Hemoglobin Variant: Hb F-Sarajevo.

    PubMed

    Lozar-Krivec, Jana; Stepic, Maja; Hovnik, Tinka; Krsnik, Mladen; Paro-Panjan, Darja

    2016-10-01

    Neonatal cyanosis is rarely due to hemoglobin variants with low oxygen affinity. We describe the clinical course and results of molecular genetic analysis of a boy who presented after birth with severe cyanosis. Arterial blood-gas analysis demonstrated a pronounced shift of the oxygen-hemoglobin dissociation curve to the right and molecular genetic analysis revealed a γ-globin variant, Hb F-Sarajevo. The patient presented is the second reported case of neonatal cyanosis due to this mutation, which was first described in 2012 by Zimmermann-Baer and coauthors. With the introduction of universal screening for congenital heart disease, the finding of low oxygen saturation will uncover more neonates with hemoglobinopathies with low oxygen affinity. PMID:27571121

  7. The Linkage Between Oxygenation and Subunit Dissociation in Human Hemoglobin

    PubMed Central

    Ackers, Gary K.; Halvorson, Herbert R.

    1974-01-01

    The use of subunit dissociation as a means of probing intersubunit contact energy changes which accompany cooperative ligand binding has been studied for the case of human hemoglobin. An analysis is presented delineating the information that can be obtained from the linkage relationships between ligand binding and subunit dissociation of hemoglobin tetramers into dimers. The analysis defines (a) the variation of the saturation function, Ȳ, with total protein concentration, (b) the variation of the subunit dissociation constant xK2 with ligand concentration (X) and (c) the correlations between changes in dimer-dimer contact energy and the sequential ligand binding steps. Sensitivity of the linkage function has been explored by numerical simulation. It is shown that subunit dissociation may appreciably affect oxygenation curves under usual conditions of measurement and that relying solely on either xK2 or Ȳ may lead to incorrect picutres of the energetics, whereas the combination defines the system much more exactly. PMID:4530985

  8. Double filaments in fibers and crystals of deoxygenated hemoglobin S

    SciTech Connect

    Magdoff-Fairchild, B.; Chiu, C.C.

    1980-10-01

    Sickle cell hemoglobin (HbS) molecules in solution or in SS erythrocytes (those from individuals homozygous for the sickle hemoglobin gene), when deoxygenated, aggregate to form fibers that pack into paracrystalline arrays. The diminished oxygen affinity of HbS is produced by the polymerization, and the distortion of the pliant erythrocyte membrane is produced by the polymerization, and the distortion of the pliant erythrocyte membrane in sickle cell disease results from the elongation of polymers and their subsequent alignment. One of the important problems to be solved in sickle cell disease is the definition of the intermolecular interactions that stabilize the fiber structure. Knowledge of these interactions might lead to the design of stereospecific antisickling agents for clinical use that could inhibit polymerization or could at least destabilize the fiber.

  9. Bitter peptide from hemoglobin hydrolysate: isolation and characterization.

    PubMed

    Aubes-Dufau, I; Capdevielle, J; Seris, J L; Combes, D

    1995-05-01

    Two separation methods, ultrafiltration and 2-butanol extraction, have shown that a peptide is the major agent responsible for bitterness in peptic hemoglobin hydrolysates. It was easily purified from these complex mixtures by specific hydrophobic adsorption on Superose 12, a gel-filtration column, which could constitute an original and interesting method for bitterness detection. The bitter peptide which corresponded to VV-hemorphin 7, the fragment 32-40 of the beta chain of bovine hemoglobin, is first generated during proteolysis, then hydrolysed by pepsin. It exhibited a strong bitterness at 0.25 mM equivalent to 0.073 mM quinine sulfate or 21 mM caffeine.

  10. Water buffalo (Bubalus bubalis) hemoglobins: an electrophoretic and chromatographic study.

    PubMed

    Di Luccia, A; Iannibelli, L; Ferranti, P; Iorio, M; Annunziata, M; Ferrara, L

    1989-01-01

    1. Hemoglobins from three phenotypes of Italian water buffalo (Bubalus bubalis), named AA, AB and BB, were selected by starch gel electrophoresis at alkaline pH and analyzed using polyacrylamide gel isoelectric focusing and subsequent analysis of titration curves to reveal differences between two types of hemoglobin identified as Hb fast and Hb slow. 2. Globins from Hb fast and Hb slow were purified by fast protein liquid chromatography (FPLC). Electrophoretic differences were found in the respective alpha-chains using polyacrylamide gel disc-electrophoresis at acid pH, polyacrylamide gel isoelectric focusing and by subsequently analyzing titration curves. 3. The results suggest that the alpha chains of Hb fast and Hb slow, called I alpha and II alpha, respectively, differ in at least two aminoacid residues. Subsequently, these amino acids were identified as lysine and cysteine.

  11. A Membrane-bound Hemoglobin from Gills of the Green Shore Crab Carcinus maenas*

    PubMed Central

    Ertas, Beyhan; Kiger, Laurent; Blank, Miriam; Marden, Michael C.; Burmester, Thorsten

    2011-01-01

    Most hemoglobins serve for the transport or storage of O2. Although hemoglobins are widespread in “entomostracan” Crustacea, malacostracans harbor the copper-containing hemocyanin in their hemolymph. Usually, only one type of respiratory protein occurs within a single species. Here, we report the identification of a hemoglobin of the shore crab Carcinus maenas (Malacostraca, Brachyura). In contrast to the dodecameric hemocyanin of this species, C. maenas hemoglobin does not reside in the hemolymph but is restricted to the gills. Immunofluorescence studies and cell fractioning showed that C. maenas hemoglobin resides in the membrane of the chief cells of the gill. To the best of our knowledge, this is the first time that a membrane-bound hemoglobin has been identified in eukaryotes. Bioinformatic evaluation suggests that C. maenas hemoglobin is anchored in the membrane by N-myristoylation. Recombinant C. maenas hemoglobin has a hexacoordinate binding scheme at the Fe2+ and an oxygen affinity of P50 = 0.5 Torr. A rapid autoxidation rate precludes a function as oxygen carrier. We rather speculate that, analogous to prokaryotic membrane-globins, C. maenas hemoglobin carries out enzymatic functions to protect the lipids in cell membrane from reactive oxygen species. Sequence comparisons and phylogenetic studies suggested that the ancestral arthropod hemoglobin was most likely an N-myristoylated protein that did not have an O2 supply function. True respiratory hemoglobins of arthropods, however, evolved independently in chironomid midges and branchiopod crustaceans. PMID:21118803

  12. IsdB-dependent hemoglobin binding is required for acquisition of heme by Staphylococcus aureus.

    PubMed

    Pishchany, Gleb; Sheldon, Jessica R; Dickson, Claire F; Alam, Md Tauqeer; Read, Timothy D; Gell, David A; Heinrichs, David E; Skaar, Eric P

    2014-06-01

    Staphylococcus aureus is a Gram-positive pathogen responsible for tremendous morbidity and mortality. As with most bacteria, S. aureus requires iron to cause disease, and it can acquire iron from host hemoglobin. The current model for staphylococcal hemoglobin-iron acquisition proposes that S. aureus binds hemoglobin through the surface-exposed hemoglobin receptor IsdB. IsdB removes heme from bound hemoglobin and transfers this cofactor to other proteins of the Isd system, which import and degrade heme to release iron in the cytoplasm. Here we demonstrate that the individual components of the Isd system are required for growth on low nanomolar concentrations of hemoglobin as a sole source of iron. An in-depth study of hemoglobin binding by IsdB revealed key residues that are required for hemoglobin binding. Further, we show that these residues are necessary for heme extraction from hemoglobin and growth on hemoglobin as a sole iron source. These processes are found to contribute to the pathogenicity of S. aureus in a murine model of infection. Together these results build on the model for Isd-mediated hemoglobin binding and heme-iron acquisition during the pathogenesis of S. aureus infection.

  13. IsdB-dependent Hemoglobin Binding Is Required for Acquisition of Heme by Staphylococcus aureus

    PubMed Central

    Pishchany, Gleb; Sheldon, Jessica R.; Dickson, Claire F.; Alam, Md Tauqeer; Read, Timothy D.; Gell, David A.; Heinrichs, David E.; Skaar, Eric P.

    2014-01-01

    Staphylococcus aureus is a Gram-positive pathogen responsible for tremendous morbidity and mortality. As with most bacteria, S. aureus requires iron to cause disease, and it can acquire iron from host hemoglobin. The current model for staphylococcal hemoglobin-iron acquisition proposes that S. aureus binds hemoglobin through the surface-exposed hemoglobin receptor IsdB. IsdB removes heme from bound hemoglobin and transfers this cofactor to other proteins of the Isd system, which import and degrade heme to release iron in the cytoplasm. Here we demonstrate that the individual components of the Isd system are required for growth on low nanomolar concentrations of hemoglobin as a sole source of iron. An in-depth study of hemoglobin binding by IsdB revealed key residues that are required for hemoglobin binding. Further, we show that these residues are necessary for heme extraction from hemoglobin and growth on hemoglobin as a sole iron source. These processes are found to contribute to the pathogenicity of S. aureus in a murine model of infection. Together these results build on the model for Isd-mediated hemoglobin binding and heme-iron acquisition during the pathogenesis of S. aureus infection. PMID:24338348

  14. Comparison of the hemoglobins of the platyhelminths Gastrothylax crumenifer and Paramphistomum epiclitum (Trematoda: Paramphistomatidae).

    PubMed

    Haque, M; Rashid, K A; Stern, M S; Sharma, P K; Siddiqi, A H; Vinogradov, S N; Walz, D A

    1992-04-01

    1. Gastrothylax crumenifer and Paramphistomum epiclitum parasitize the water buffalo Bubalus bubalis. 2. Gastrothylas hemoglobin consisted of two fractions of ca 30,000 and ca 18,000 by gel filtration. SDS-electrophoresis showed both to be single, ca 15,000 chains. 3. Paramphistomum hemoglobin was ca 16,000 by both gel filtration and SDS-electrophoresis. 4. Reversed-phase chromatography of carboxymethylated trematode and buffalo globins gave single peaks and two peaks, respectively. Although Paramphistomum hemoglobin provided and N-terminal sequence, Gastrothylax hemoglobin did not, suggesting blocked N-terminals. The buffalo sequences were found to be identical to the sequences of the alpha and beta chains of bovine hemoglobin. 5. Although Paramphistomum hemoglobin consists of only one chain, Gastrothylax hemoglobin consists either of one chain which aggregates to a dimer or of two different chains, only one of which aggregates to a dimer.

  15. Chemical modifications that inhibit gelation of sickle hemoglobin.

    PubMed

    Benesch, R; Benesch, R E; Yung, S

    1974-04-01

    Substitution of the N-terminal amino groups with pyridoxal compounds inhibits gelation and increases the solubility of deoxy sickle hemoglobin (Hb S). Pyridoxylation of the alpha chains has considerably more effect than that of the beta chains. The increase in minimum gelling concentration of Hb S that results from modification of the alpha N-termini is the same as that produced by dilution of Hb S with an equal amount of Hb A. PMID:4524653

  16. Hemoglobin Status and Externalizing Behavioral Problems in Children

    PubMed Central

    Su, Jianhua; Cui, Naixue; Zhou, Guoping; Ai, Yuexian; Sun, Guiju; Zhao, Sophie R.; Liu, Jianghong

    2016-01-01

    Background: Still considered one of the most prevalent nutritional problems in the world, anemia has been shown in many studies to have deleterious effects on neurobehavioral development. While most research efforts have focused on investigating the effects of anemia on social and emotional development of infants by using a cross-sectional design, research is still needed to investigate whether early childhood anemia, beyond infantile years, is linked with behavioral problems. Objective: This study assessed whether (1) hemoglobin (Hb) levels in early childhood are associated with externalizing behavior; and (2) this relationship is confounded by social adversity. Methods: Hemoglobin levels were taken from children (N = 98) of the China Jintan Cohort Study at age 4 years, and externalizing behaviors (attention and aggression) were assessed with the Child Behavior Checklist (ASEBA-CBCL) at age 6 years (mean age 5.77 ± 0.39 years old). Results: Compared with other children in the sample, children with relatively lower Hb levels at age 4 had more behavioral problems in both attention and aggression at age 6, independent of social adversity. For boys, this association was significant for attention problems, which did not interact with social adversity. For girls, the association was significant for aggression, which interacted with social adversity. While girls on average exhibited higher social adversity than boys, the main effect of Hb was only significant in girls with low social adversity. Conclusions: These results indicate that there is an inverse association between hemoglobin levels and later behavioral problems. Findings of this study suggest that regular monitoring of children’s hemoglobin levels and appropriate intervention may help with early identification of behavioral problems. PMID:27472352

  17. Multimeric hemoglobin of the Australian brine shrimp Parartemia.

    PubMed

    Coleman, M; Matthews, C M; Trotman, C N

    2001-04-01

    The hemoglobin molecule of the commercially important brine shrimp Artemia sp. has been used extensively as a model for the study of molecular evolution. It consists of nine globin domains joined by short linker sequences, and these domains are believed to have originated through a series of duplications from an original globin gene. In addition, in Artemia, two different polymers of hemoglobin, called C and T, are found which differ by 11.7% at the amino acid level and are believed to have diverged about 60 MYA. This provides a set of data of 18 globin domain sequences that have evolved in the same organism. The pattern of amino acid substitution between these two polymers is unusual, with pairs of equivalent domains displaying differences of up to 2.7-fold in total amino acid substitution. Such differences would reflect a similar range of molecular-clock rates in what appear to be duplicate, structurally equivalent domains. In order to provide a reference outgroup, we sequenced the cDNA for a nine-domain hemoglobin (P) from another genus of brine shrimp, Parartemia zietziana, which differs morphologically and ecologically from Artemia and is endemic to Australia. Parartemia produces only one hundredth the amount of hemoglobin that Artemia produces and does not upregulate production in response to low oxygen partial pressure. Comparison of the globin domains at the amino acid and DNA levels suggests that the Artemia globin T gene has accumulated substitutions differently from the Parartemia P and Artemia C globin genes. We discuss the questions of accelerated evolution after duplication and possible functions for the Parartemia globin. PMID:11264409

  18. Hemoglobin-based red blood cell substitutes and nitric oxide.

    PubMed

    Yu, Binglan; Bloch, Kenneth D; Zapol, Warren M

    2009-04-01

    Hemoglobin-based oxygen carriers (HBOCs) have been studied for decades as red blood cell substitutes. Profound vasoconstrictor effects have limited the clinical utility of HBOCs and are attributable to avid scavenging of nitric oxide (NO). Inhaling NO can charge the body's stores of NO metabolites without producing hypotension and can prevent systemic hypertension induced when HBOCs are subsequently infused. Concurrent breathing of low NO doses can prevent pulmonary vasoconstriction after HBOC infusion without augmenting plasma methemoglobinemia.

  19. Initial studies of hypoxic radioprotection by deoxygenated dextran-hemoglobin

    SciTech Connect

    Hill, R.P.; Porter, L.S.; Ives, S.A.; Wong, J.T.F.

    1984-03-01

    Initial studies were performed to examine the potential of perfused dextran-hemoglobin to protect pig skin or mouse bone marrow cells against radiation damage. Some protection was indicated in both systems. In the pig skin a protection factor of 1.5 was observed for moist desquamation, and 2.0 for necrosis. These results suggest the possibility of using blood substitutes to induce tissue hypoxia for therapeutic purposes.

  20. Hemoglobin s polymerization and red cell membrane changes.

    PubMed

    Kuypers, Frans A

    2014-04-01

    Different pathways lead from the simple point mutation in hemoglobin to the membrane changes that characterize the altered interaction of the sickle red blood cell with its environment, including endothelial cells, white blood cells, and platelets. Polymerization and oxidation-induced damage to both lipid and protein components of the red cell membrane, as well as the generation of bioreactive membrane material (microparticles), has a profound effect on all tissues and organs, and defines the vasculopathy of the patient with sickle cell disease.

  1. Direct estimation of evoked hemoglobin changes by multimodality fusion imaging

    PubMed Central

    Huppert, Theodore J.; Diamond, Solomon G.; Boas, David A.

    2009-01-01

    In the last two decades, both diffuse optical tomography (DOT) and blood oxygen level dependent (BOLD)-based functional magnetic resonance imaging (fMRI) methods have been developed as noninvasive tools for imaging evoked cerebral hemodynamic changes in studies of brain activity. Although these two technologies measure functional contrast from similar physiological sources, i.e., changes in hemoglobin levels, these two modalities are based on distinct physical and biophysical principles leading to both limitations and strengths to each method. In this work, we describe a unified linear model to combine the complimentary spatial, temporal, and spectroscopic resolutions of concurrently measured optical tomography and fMRI signals. Using numerical simulations, we demonstrate that concurrent optical and BOLD measurements can be used to create cross-calibrated estimates of absolute micromolar deoxyhemoglobin changes. We apply this new analysis tool to experimental data acquired simultaneously with both DOT and BOLD imaging during a motor task, demonstrate the ability to more robustly estimate hemoglobin changes in comparison to DOT alone, and show how this approach can provide cross-calibrated estimates of hemoglobin changes. Using this multimodal method, we estimate the calibration of the 3 tesla BOLD signal to be −0.55% ± 0.40% signal change per micromolar change of deoxyhemoglobin. PMID:19021411

  2. Evolutionary and Functional Relationships in the Truncated Hemoglobin Family

    PubMed Central

    Bustamante, Juan P.; Radusky, Leandro; Boechi, Leonardo; Estrin, Darío A.; ten Have, Arjen; Martí, Marcelo A.

    2016-01-01

    Predicting function from sequence is an important goal in current biological research, and although, broad functional assignment is possible when a protein is assigned to a family, predicting functional specificity with accuracy is not straightforward. If function is provided by key structural properties and the relevant properties can be computed using the sequence as the starting point, it should in principle be possible to predict function in detail. The truncated hemoglobin family presents an interesting benchmark study due to their ubiquity, sequence diversity in the context of a conserved fold and the number of characterized members. Their functions are tightly related to O2 affinity and reactivity, as determined by the association and dissociation rate constants, both of which can be predicted and analyzed using in-silico based tools. In the present work we have applied a strategy, which combines homology modeling with molecular based energy calculations, to predict and analyze function of all known truncated hemoglobins in an evolutionary context. Our results show that truncated hemoglobins present conserved family features, but that its structure is flexible enough to allow the switch from high to low affinity in a few evolutionary steps. Most proteins display moderate to high oxygen affinities and multiple ligand migration paths, which, besides some minor trends, show heterogeneous distributions throughout the phylogenetic tree, again suggesting fast functional adaptation. Our data not only deepens our comprehension of the structural basis governing ligand affinity, but they also highlight some interesting functional evolutionary trends. PMID:26788940

  3. Modulating hemoglobin nitrite reductase activity through allostery: a mathematical model.

    PubMed

    Rong, Zimei; Alayash, Abdu I; Wilson, Michael T; Cooper, Chris E

    2013-11-30

    The production of nitric oxide by hemoglobin (Hb) has been proposed to play a major role in the control of blood flow. Because of the allosteric nature of hemoglobin, the nitrite reductase activity is a complex function of oxygen partial pressure PO2. We have previous developed a model to obtain the micro rate constants for nitrite reduction by R state (kR) and T state (kT) hemoglobin in terms of the experimental maximal macro rate constant kNmax and the corresponding oxygen concentration PO2max. However, because of the intrinsic difficulty in obtaining accurate macro rate constant kN, from available experiments, we have developed an alternative method to determine the micro reaction rate constants (kR and kT) by fitting the simulated macro reaction rate curve (kN versus PO2) to the experimental data. We then use our model to analyze the effect of pH (Bohr Effect) and blood ageing on the nitrite reductase activity, showing that the fall of bisphosphoglycerate (BPG) during red cell storage leads to increase NO production. Our model can have useful predictive and explanatory power. For example, the previously described enhanced nitrite reductase activity of ovine fetal Hb, in comparison to the adult protein, may be understood in terms of a weaker interaction with BPG and an increase in the value of kT from 0.0087M(-1)s(-1) to 0.083M(-1)s(-1).

  4. Vibrational modes of hemoglobin in red blood cells.

    PubMed

    Martel, P; Calmettes, P; Hennion, B

    1991-02-01

    Equine red blood cells were washed in saline heavy water (2H2O) to exchange the hydrogen atoms of the non-hemoglobin components with deuterons. This led to novel neutron scattering measurements of protein vibrations within a cellular system and permitted a comparison with inelastic neutron scattering measurements on purified horse hemoglobin, either dry or wetted with 2H2O. As a function of wavevector transfer Q and the frequency transfer v the neutron response typified by the dynamic structure factor S(Q, v) was found to be similar for extracted and cellular hemoglobin at low and high temperatures. At 77 K, in the cells, a peak in S(Q, v) due to the protein was found near 0.7 THz, approximately half the frequency of a strong peak in the aqueous medium. Measurements at higher temperatures (170 and 230 K) indicated similar small shifts downwards in the peak frequencies of both components. At 260 K the low frequency component became predominantly quasielastic, but a significant inelastic component could still be ascribed to the aqueous scattering. Near 295 K the frequency responses of both components were similar and centered near zero. When scattering due to water is taken into account it appears that the protein neutron response in, or out of, red blood cells is little affected by hydration in the low frequency regime where Van der Waals forces are thought to be effective. PMID:1849028

  5. Evolutionary and Functional Relationships in the Truncated Hemoglobin Family.

    PubMed

    Bustamante, Juan P; Radusky, Leandro; Boechi, Leonardo; Estrin, Darío A; Ten Have, Arjen; Martí, Marcelo A

    2016-01-01

    Predicting function from sequence is an important goal in current biological research, and although, broad functional assignment is possible when a protein is assigned to a family, predicting functional specificity with accuracy is not straightforward. If function is provided by key structural properties and the relevant properties can be computed using the sequence as the starting point, it should in principle be possible to predict function in detail. The truncated hemoglobin family presents an interesting benchmark study due to their ubiquity, sequence diversity in the context of a conserved fold and the number of characterized members. Their functions are tightly related to O2 affinity and reactivity, as determined by the association and dissociation rate constants, both of which can be predicted and analyzed using in-silico based tools. In the present work we have applied a strategy, which combines homology modeling with molecular based energy calculations, to predict and analyze function of all known truncated hemoglobins in an evolutionary context. Our results show that truncated hemoglobins present conserved family features, but that its structure is flexible enough to allow the switch from high to low affinity in a few evolutionary steps. Most proteins display moderate to high oxygen affinities and multiple ligand migration paths, which, besides some minor trends, show heterogeneous distributions throughout the phylogenetic tree, again suggesting fast functional adaptation. Our data not only deepens our comprehension of the structural basis governing ligand affinity, but they also highlight some interesting functional evolutionary trends.

  6. Short-lived intermediates in hemoglobin/O2 systems.

    PubMed

    Czerlinski, G; Levin, R; Ypma, T

    1998-01-01

    The kinetics of the reaction of hemoglobin with molecular oxygen, in which rapid mixing is followed by a very fast temperature jump, is numerically simulated. Values for rate constants are used to the extent known, otherwise interpolated or extrapolated. It is shown that reaction steps not resolvable by rapid mixing can be resolved by subsequent chemical relaxation at appropriate points in time. Four different mechanisms are considered, all assuming no distinction between the two kinds of chains of hemoglobin. Bimolecular rate constants for oxygen binding are either the same for all four sites, or are governed by "frequency factors" (the kinetic equivalent of statistical factors for equilibrium constants in allosteric models). Furthermore, either the third or the fourth measured (Adair) dissociation constant is composed of the product of a "local" dissociation constant and an allosteric interconversion constant. These two pairs of choices give rise to four different mechanisms. Can these mechanisms be distinguished experimentally? As the final parameter values are so similar for the first two binding steps, discrimination is essentially impossible at low oxygen concentration levels (less than 100 microM with 50 microM hemoglobin). Discrimination becomes possible at higher oxygen concentrations, but high resolution in time and concentration amplitude are required. Much depends upon the differences in molar extinction coefficients of components over the accessible wave length range. Some of these values are as yet unknown or not known to a sufficient precision. Nevertheless, distinction between mechanistic alternatives is possible in principle.

  7. Pancreatic ascites hemoglobin contributes to the systemic response in acute pancreatitis.

    PubMed

    Pérez, Salvador; Pereda, Javier; Sabater, Luis; Sastre, Juan

    2015-04-01

    Upon hemolysis extracellular hemoglobin causes oxidative stress and cytotoxicity due to its peroxidase activity. Extracellular hemoglobin may release free hemin, which increases vascular permeability, leukocyte recruitment, and adhesion molecule expression. Pancreatitis-associated ascitic fluid is reddish and may contain extracellular hemoglobin. Our aim has been to determine the role of extracellular hemoglobin in the local and systemic inflammatory response during severe acute pancreatitis in rats. To this end we studied taurocholate-induced necrotizing pancreatitis in rats. First, extracellular hemoglobin in ascites and plasma was quantified and the hemolytic action of ascitic fluid was tested. Second, we assessed whether peritoneal lavage prevented the increase in extracellular hemoglobin in plasma during pancreatitis. Third, hemoglobin was purified from rat erythrocytes and administered intraperitoneally to assess the local and systemic effects of ascitic-associated extracellular hemoglobin during acute pancreatitis. Extracellular hemoglobin and hemin levels markedly increased in ascitic fluid and plasma during necrotizing pancreatitis. Peroxidase activity was very high in ascites. The peritoneal lavage abrogated the increase in extracellular hemoglobin in plasma. The administration of extracellular hemoglobin enhanced ascites; dramatically increased abdominal fat necrosis; upregulated tumor necrosis factor-α, interleukin-1β, and interleukin-6 gene expression; and decreased expression of interleukin-10 in abdominal adipose tissue during pancreatitis. Extracellular hemoglobin enhanced the gene expression and protein levels of vascular endothelial growth factor (VEGF) and other hypoxia-inducible factor-related genes in the lung. Extracellular hemoglobin also increased myeloperoxidase activity in the lung. In conclusion, extracellular hemoglobin contributes to the inflammatory response in severe acute pancreatitis through abdominal fat necrosis and inflammation

  8. Fasting serum glucose and glycosylated hemoglobin level in obesity.

    PubMed

    Das, R K; Nessa, A; Hossain, M A; Siddiqui, N I; Hussain, M A

    2014-04-01

    Obesity is a condition in which the body fat stores are increased to an extent which impairs health and leads to serious health consequences. The amount of body fat is difficult to measure directly, and is usually determined from an indirect measure - the body mass index (BMI). Increased BMI in obese persons is directly associated with an increase in metabolic disease, such as type 2 diabetes mellitus. This Analytical cross sectional study was undertaken to assess the relation between obesity and glycemic control of body by measuring fasting serum glucose and glycosylated hemoglobin. This study was carried out in the Department of Physiology, Mymensingh Medical College, Mymensingh from 1st July 2011 to 30th June 2012 on 120 equally divided male and female persons within the age range of 25 to 55 years. Age more than 55 years and less than 25 years and diagnosed case of Hypothyroidism, Cushing's syndrome, polycystic ovary, Antipsychotic drug user and regular steroid users were excluded. Non probability purposive type of sampling technique was used for selecting the study subjects. Measurement of body mass index was done as per procedure. Fasting serum glucose was estimated by glucose oxidase method and Glycosylated hemoglobin by Boronate Affinity method. Statistical analysis was done by SPSS (version 17.0). Data were expressed as Mean±SE and statistical significance of difference among the groups were calculated by unpaired student's 't' test and Pearson's correlation coefficient tests were done as applicable. The Mean±SE of fasting serum glucose was significant at 1% level (P value <0.001) for obese group of BMI. There was no significant difference of glycosylated hemoglobin level between control and study groups. But there was positive correlation within each group. Fasting serum glucose also showed a bit stronger positive correlation with BMI. Both obese male and female persons showed higher levels of fasting serum glucose and glycosylated hemoglobin. The

  9. Hemoglobin redux: combining neutron and X-ray diffraction with mass spectrometry to analyse the quaternary state of oxidized hemoglobins

    PubMed Central

    Mueser, Timothy C.; Griffith, Wendell P.; Kovalevsky, Andrey Y.; Guo, Jingshu; Seaver, Sean; Langan, Paul; Hanson, B. Leif

    2010-01-01

    Improvements in neutron diffraction instrumentation are affording the opportunity to re-examine the structures of vertebrate hemoglobins and to interrogate proton and solvent position changes between the different quaternary states of the protein. For hemoglobins of unknown primary sequence, structural studies of cyanomethemoglobin (CNmetHb) are being used to help to resolve sequence ambiguity in the mass spectra. These studies have also provided additional structural evidence for the involvement of oxidized hemoglobin in the process of erythrocyte senescence. X-ray crystal studies of Tibetan snow leopard CNmetHb have shown that this protein crystallizes in the B state, a structure with a more open dyad, which possibly has relevance to RBC band 3 protein binding and erythrocyte senescence. R-state equine CNmetHb crystal studies elaborate the solvent differences in the switch and hinge region compared with a human deoxyhemoglobin T-­state neutron structure. Lastly, comparison of histidine protonation between the T and R state should enumerate the Bohr-effect protons. PMID:21041946

  10. Hemoglobin redux: combining neutron and X-ray diffraction with mass spectrometry to analyse the quaternary state of oxidized hemoglobins

    SciTech Connect

    Mueser, Timothy C. Griffith, Wendell P.; Kovalevsky, Andrey Y.; Guo, Jingshu; Seaver, Sean; Langan, Paul; Hanson, B. Leif

    2010-11-01

    X-ray and neutron diffraction studies of cyanomethemoglobin are being used to evaluate the structural waters within the dimer–dimer interface involved in quaternary-state transitions. Improvements in neutron diffraction instrumentation are affording the opportunity to re-examine the structures of vertebrate hemoglobins and to interrogate proton and solvent position changes between the different quaternary states of the protein. For hemoglobins of unknown primary sequence, structural studies of cyanomethemoglobin (CNmetHb) are being used to help to resolve sequence ambiguity in the mass spectra. These studies have also provided additional structural evidence for the involvement of oxidized hemoglobin in the process of erythrocyte senescence. X-ray crystal studies of Tibetan snow leopard CNmetHb have shown that this protein crystallizes in the B state, a structure with a more open dyad, which possibly has relevance to RBC band 3 protein binding and erythrocyte senescence. R-state equine CNmetHb crystal studies elaborate the solvent differences in the switch and hinge region compared with a human deoxyhemoglobin T-state neutron structure. Lastly, comparison of histidine protonation between the T and R state should enumerate the Bohr-effect protons.

  11. Hemoglobin redux: combining neutron and X-ray diffraction with mass spectrometry to analyse the quaternary state of oxidized hemoglobins.

    PubMed

    Mueser, Timothy C; Griffith, Wendell P; Kovalevsky, Andrey Y; Guo, Jingshu; Seaver, Sean; Langan, Paul; Hanson, B Leif

    2010-11-01

    Improvements in neutron diffraction instrumentation are affording the opportunity to re-examine the structures of vertebrate hemoglobins and to interrogate proton and solvent position changes between the different quaternary states of the protein. For hemoglobins of unknown primary sequence, structural studies of cyanomethemoglobin (CNmetHb) are being used to help to resolve sequence ambiguity in the mass spectra. These studies have also provided additional structural evidence for the involvement of oxidized hemoglobin in the process of erythrocyte senescence. X-ray crystal studies of Tibetan snow leopard CNmetHb have shown that this protein crystallizes in the B state, a structure with a more open dyad, which possibly has relevance to RBC band 3 protein binding and erythrocyte senescence. R-state equine CNmetHb crystal studies elaborate the solvent differences in the switch and hinge region compared with a human deoxyhemoglobin T-state neutron structure. Lastly, comparison of histidine protonation between the T and R state should enumerate the Bohr-effect protons.

  12. Lipid peroxidation and hemoglobin degradation in red blood cells exposed to t-butyl hydroperoxide. Dependence on glucose metabolism and hemoglobin status.

    PubMed

    Trotta, R J; Sullivan, S G; Stern, A

    1981-12-01

    Changes in hemoglobin status and lipid peroxidation were followed in red cells containing either oxy-met-, or carbonmonoxyhemoglobin, incubated with t-butyl hydroperoxide in a medium with or without glucose. Loss of intact hemoglobin (the sum of oxyhemoglobin and methemoglobin) was inversely proportional to the degree of lipid peroxidation in red cells containing either oxy- or methemoglobin. When glucose was added to the medium, lipid peroxidation increased while there was a decreased loss of intact hemoglobin in red cells containing either oxy- or methemoglobin, while both lipid peroxidation and changes in hemoglobin decreased in red cells containing carbonmonoxyhemoglobin. Methemoglobin formation and loss of intact hemoglobin were directly proportional to the degree of lipid peroxidation in red cells containing carbonmonoxyhemoglobin. The greatest amount of lipid peroxidation occurred in red cells containing carbonmonoxyhemoglobin, incubated without glucose. These results indicate that methemoglobin and non-intact hemoglobin may protect the membrane against lipid peroxidation. We propose that, depending on the availability of glucose and the liganded state of hemoglobin, lipid peroxidation and hemoglobin alterations represent extremes of a spectrum of oxidative damage.

  13. Specific induction of fibronectin binding activity by hemoglobin in Candida albicans grown in defined media.

    PubMed

    Yan, S; Nègre, E; Cashel, J A; Guo, N; Lyman, C A; Walsh, T J; Roberts, D D

    1996-08-01

    Fibronectin (FN) is a major component of host extracellular matrix that may play an important role in the initiation and dissemination of Candida albicans infections. Expression of FN binding requires growth of C albicans blastoconidia in complex medium, and the regulation of FN receptor expression is poorly understood. We now demonstrate that hemoglobin is a potent and specific inducer of FN receptor expression and describe a defined medium supplemented with hemoglobin that greatly and stably enhances the binding activity of C. albicans for soluble FN. Enhancement of FN binding by hemoglobin in strain 44807 was concentration dependent and was maximal at 0.1% hemoglobin with 20- to 80-fold enhancement. The hemoglobin-induced FN binding to C. albicans was saturable, with a Kd of 2.7 X 10(-8) M. Enhancement required growth of C. albicans in hemoglobin-containing medium, since simply exposing blastoconidia to hemoglobin in a nongrowing status did not enhance binding. Induction was reversible following removal of hemoglobin from the growth medium and not associated with germination. Inorganic or protein-bound iron was not sufficient for the induction, since other iron-containing proteins or inorganic iron salts were inactive. Growth in the simple medium yeast nitrogen base supplemented with hemoglobin increased cell adhesion to immobilized FN and to cultured monolayers of bovine corneal endothelial cells. These data suggest that hemoglobin may be an important regulator of FN binding activity in C. albicans and thus may play a role in its pathogenesis. PMID:8757815

  14. Hemoglobin E: a common hemoglobinopathy among children of Southeast Asian origin.

    PubMed

    Katsanis, E; Luke, K H; Hsu, E; Yates, J R

    1987-07-01

    With the recent immigration of Southeast Asians to Canada, hemoglobin E has become a frequent diagnosis. The clinical and hematologic findings in 42 children (mean age 4.3 years) with hemoglobin E are presented. There were 33 heterozygotes (having hemoglobin E trait), 6 homozygotes (having hemoglobin EE) and 3 double heterozygotes (having hemoglobin E-beta-thalassemia). The heterozygotes had low-normal hemoglobin levels and mean corpuscular volumes; coexisting iron deficiency, present in 62% of these children, resulted in substantially lower hemoglobin levels, very low mean corpuscular volumes and lower than expected levels of hemoglobin E on electrophoresis. The children with hemoglobin EE were only slightly anemic, but those with hemoglobin E-beta-thalassemia had severe anemia and required long-term transfusion therapy. Nutritional factors and parasitic infestations were the main causes of iron depletion, which was common, particularly in children less than 2 years old (87%). Physicians of patients of Southeast Asian origin should be aware of the clinical and hematologic presentation of these hemoglobinopathies.

  15. Unexpectedly low pulse oximetry measurements associated with variant hemoglobins: a systematic review.

    PubMed

    Verhovsek, Madeleine; Henderson, Matthew P A; Cox, Gerard; Luo, Hong-yuan; Steinberg, Martin H; Chui, David H K

    2010-11-01

    Pulse oximetry estimates arterial blood oxygen saturation based on light absorbance of oxy- and deoxy-hemoglobin at 660 and 940 nm wavelengths. Patients with unexpectedly low SpO₂ often undergo cardio-pulmonary testing to ascertain the cause of their hypoxemia. However, in a subset of patients, a variant hemoglobin is responsible for low SpO₂ measurements. The extent of this problem is unclear. We performed a systematic literature review for reports of low SpO₂ associated with variant hemoglobins. We also reviewed unpublished cases from an academic hemoglobin diagnostic reference laboratory. Twenty-five publications and four unpublished cases were identified, representing 45 patients with low SpO₂ and confirmed variant hemoglobin. Fifty-seven family members of patients had confirmed or suspected variant hemoglobin. Three low oxygen affinity variant hemoglobins had concordantly low SpO₂ and SaO₂. Eleven variant hemoglobins were associated with unexpectedly low SpO₂ measurements but normal SaO₂. Hemoglobin light absorbance testing was reported in three cases, all of which showed abnormal absorption spectra between 600 and 900 nm. Seven other variant hemoglobins had decreased SpO₂, with unreported or uncertain SaO₂. Twenty-one variant hemoglobins were found to be associated with low SpO₂. Most variant hemoglobins were associated with spuriously low SpO₂. Abnormal absorption spectra explain the discrepancy between SpO₂ and SaO(2) for some variants. The differential diagnosis of possible variant hemoglobin ought to be considered in asymptomatic patients found to have unexpectedly low SpO₂. The correct diagnosis will help to spare patients from unnecessary investigations and anxiety.

  16. Oxygen equilibria of ectotherm blood containing multiple hemoglobins.

    PubMed

    Maginniss, L A; Song, Y K; Reeves, R B

    1980-12-01

    Complete isocapnic O2 equilibrium curves (O2EC's) and related blood-gas properties are reported for whole blood of the bullfrog (Rana catesbeiana) and the aquatic turtle (Pseudemys scripta) at temperatures ranging from 5 to 35 degrees C. P50's for bullfrog and turtle blood at physiological pH and 25 degrees C were 36.6 Torr (pH 7.83) and 19.3 Torr (pH 7.55), respectively. Elevation of blood temperature significantly reduced hemoglobin oxygen affinity in both species (delta H = -8.1 and -7.8 kcal/mol O2 for Rana and Pseudemys, respectively). Bullfrog and turtle oxygen equilibrium data revealed non-standard curve shapes when compared with the Severinghaus curve for human blood (1979); ectotherm O2EC's rose more steeply below P50 (less sigmoid) and were distinctly flattened (linear) above 50% saturation. The CO2-Bohr effect for bullfrog and turtle blood varied significantly as a function of saturation. In addition, both species exhibited non-linear Hill relationships (logS/1-s vs. log PO2). These results indicate that the oxygen binding properties of the multiple hemoglobin bloods of Rana and Pseudemys (demonstrated by isoelectric focusing) are more complex than those exhibited by normal human blood. As a consequence, these ectotherm blood oxygen data are not well characterized by the limited number of simple descriptive parameters (P50, Hill's n and delta log P50/delta pH) commonly used to delineate predominantly single hemoglobin systems.

  17. Mass Spectra and Ion Collision Cross Sections of Hemoglobin

    NASA Astrophysics Data System (ADS)

    Kang, Yang; Terrier, Peran; Douglas, D. J.

    2011-02-01

    Mass spectra of commercially obtained hemoglobin (Hb) show higher levels of monomer and dimer ions, heme-deficient dimer ions, and apo-monomer ions than hemoglobin freshly prepared from blood. This has previously been attributed to oxidation of commercial Hb. Further, it has been reported that that dimer ions from commercial bovine Hb have lower collision cross sections than low charge state monomer ions. To investigate these effects further, we have recorded mass spectra of fresh human Hb, commercial human and bovine Hb, fresh human Hb oxidized with H2O2, lyophilized fresh human Hb, fresh human Hb both lyophilized and chemically oxidized, and commercial human Hb oxidized with H2O2. Masses of α-monomer ions of all hemoglobins agree with the masses expected from the sequences within 3 Da or better. Mass spectra of the β chains of commercial Hb and oxidized fresh human Hb show a peak or shoulder on the high mass side, consistent with oxidation of the protein. Both commercial proteins and oxidized fresh human Hb produce heme-deficient dimers with masses 32 Da greater than expected and higher levels of monomer and dimer ions than fresh Hb. Lyophilization or oxidation of Hb both produce higher levels of monomer and dimer ions in mass spectra. Fresh human Hb, commercial human Hb, commercial bovine Hb, and oxidized commercial human Hb all give dimer ions with cross sections greater than monomer ions. Thus, neither oxidation of Hb or the difference in sequence between human and bovine Hb make substantial differences to cross sections of ions.

  18. New-old hemoglobin-like proteins of symbiotic dinoflagellates

    PubMed Central

    Rosic, Nedeljka N; Leggat, William; Kaniewska, Paulina; Dove, Sophie; Hoegh-Guldberg, Ove

    2013-01-01

    Symbiotic dinoflagellates are unicellular photosynthetic algae that live in mutualistic symbioses with many marine organisms. Within the transcriptome of coral endosymbionts Symbiodinium sp. (type C3), we discovered the sequences of two novel and highly polymorphic hemoglobin-like genes and proposed their 3D protein structures. At the protein level, four isoforms shared between 87 and 97% sequence identity for Hb-1 and 78–99% for Hb-2, whereas between Hb-1 and Hb-2 proteins, only 15–21% sequence homology has been preserved. Phylogenetic analyses of the dinoflagellate encoding Hb sequences have revealed a separate evolutionary origin of the discovered globin genes and indicated the possibility of horizontal gene transfer. Transcriptional regulation of the Hb-like genes was studied in the reef-building coral Acropora aspera exposed to elevated temperatures (6–7°C above average sea temperature) over a 24-h period and a 72-h period, as well as to nutrient stress. Exposure to elevated temperatures resulted in an increased Hb-1 gene expression of 31% after 72 h only, whereas transcript abundance of the Hb-2 gene was enhanced by up to 59% by both 1-day and 3-day thermal stress conditions. Nutrient stress also increased gene expression of Hb-2 gene by 70%. Our findings describe the differential expression patterns of two novel Hb genes from symbiotic dinoflagellates and their polymorphic nature. Furthermore, the inducible nature of Hb-2 gene by both thermal and nutrient stressors indicates a prospective role of this form of hemoglobin in the initial coral–algal responses to changes in environmental conditions. This novel hemoglobin has potential use as a stress biomarker. PMID:23610627

  19. Differential expression of murine adult hemoglobins in early ontogeny

    SciTech Connect

    Wawrzyniak, C.J.; Lewis, S.E.; Popp, R.A.

    1985-01-01

    A hemoglobin mutation is described that permits study of the expression of the two adult ..beta..-globin genes throughout fetal and postnatal development. Mice with a mutation at the Hbb/sup s/, ..beta..-globin locus, were used to study the relative levels of ..beta..-s2major and ..beta..-sminor globins specified by the mutant Hbb/sup s2/ haplotype during development. At 11.5 days of gestation ..beta..-sminor comprised over 80% and ..beta..-s2major under 20% of the adult beta-globin. The relative level of ..beta..-sminor decreased through fetal development; at birth ..beta..-sminor represented 33.7% of the ..beta..-globin. The adult values of 71.0% ..beta..-s2major and 29.0% ..beta..-sminor globin are expressed in mice six days after birth. Because the two ..beta..-globin genes are expressed in mice of the Hbb/sup 2s/ haplotype, both the ..beta..-smajor and ..beta..-sminor genes must be expressed in mice of the Hbb/sup s/ haplotype. Expression of the ..beta..-sminor gene is elevated to 35.6% in Hbb/sup s2/ mice that have been bled repeatedly. Thus, the 5' ..beta..-s2major and 3' ..beta..-sminor genes of the Hbb/sup s2/ haplotype and, presumably the 5' ..beta..-smajor and 3' ..beta..-sminor genes of the Hbb/sup s/ haplotype, are regulated independently and are homologous to the 5' ..beta..-dmajor and 3' ..beta..-dminor genes of the Hbb/sup d/ haplotype. Mice of the Hbb/sup s2/ haplotype are better than mice of the Hbb/sup d/ haplotytpe for studying the mechanisms of hemoglobin switching because the Hbb/sup s2/ each of the three embryonic and two adult hemoglobins can be separated by electrophoresis. 17 refs., 3 figs.

  20. Monoclonal antibodies to human hemoglobin S and cell lines for the production thereof

    DOEpatents

    Jensen, R.H.; Vanderlaan, M.; Bigbee, W.L.; Stanker, L.H.; Branscomb, E.W.; Grabske, R.J.

    1984-11-29

    The present invention provides monoclonal antibodies specific to and distinguishing between hemoglobin S and hemoglobin A and methods for their production and use. These antibodies are capable of distinguishing between two hemoglobin types which differ from each other by only a single amino acid residue. The antibodies produced according to the present method are useful as immunofluorescent markers to enumerate circulating red blood cells which have the property of altered expression of the hemoglobin gene due to somatic mutation in stem cells. Such a measurement is contemplated as an assay for in vivo cellular somatic mutations in humans. Since the monoclonal antibodies produced in accordance with the instant invention exhibit a high degree of specificity to and greater affinity for hemoglobin S, they are suitable for labeling human red blood cells for flow cytometric detection of hemoglobin genotype. 4 figs.

  1. Sickle cell anemia: targeting the role of fetal hemoglobin in therapy.

    PubMed

    Coleman, Emma; Inusa, Baba

    2007-06-01

    Sickle cell anemia results from the single amino acid substitution of valine for glutamic acid in the beta-chain owing to a nucleotide defect that causes the production of abnormal beta-chains in hemoglobin S. Abnormal hemoglobin chains form polymers in the deoxygenated state, leading to the characteristic sickle cells. The polymerization of deoxygenated hemoglobin S accounts for the pathologic changes in sickle cell disease. The main-stay of therapy in sickle cell disease aims to reduce the amount of sickled hemoglobin present through the prevention of polymerization and reversal of this process. One way of discouraging polymerization is to increase the level of fetal hemoglobin, which because of its high oxygen affinity, does not participate in the polymerization process. Fetal hemoglobin production may be induced pharmacologically or by the use of gene therapy and genetic engineering techniques. PMID:17556734

  2. Long-term variation in hemoglobin concentration in nestling great tits Parus major.

    PubMed

    Kaliński, Adam; Bańbura, Mirosława; Glądalski, Michał; Markowski, Marcin; Skwarska, Joanna; Wawrzyniak, Jarosław; Zieliński, Piotr; Cyżewska, Iwona; Bańbura, Jerzy

    2015-07-01

    Several studies have previously proposed that blood hemoglobin concentration in nestling passerines is a reliable index of individual condition and nutritional state. In this paper we present results concerning variation in hemoglobin concentration in the blood of ca. 14-day-old nestling great tits Parus major in central Poland in an 11-year-long period, 2003-2013, in two distinct habitat types: urban park and deciduous forest. The most important findings of the study were: (i) variation in hemoglobin concentration was consistent within broods, (ii) hemoglobin concentration of nestlings varied markedly across years, (iii) hemoglobin concentration was significantly higher in the forest study site which is richer in terms of food abundance during the short period of tits breeding season and (iv) high hemoglobin level was a predictor of nestling survival from hatching to fledging.

  3. Monoclonal antibodies to human hemoglobin S and cell lines for the production thereof

    DOEpatents

    Jensen, Ronald H.; Vanderlaan, Martin; Bigbee, William L.; Stanker, Larry H.; Branscomb, Elbert W.; Grabske, Robert J.

    1988-01-01

    The present invention provides monoclonal antibodies specific to and distinguish between hemoglobin S and hemoglobin A and methods for their production and use. These antibodies are capable of distinguishing between two hemoglobin types which differ from each other by only a single amino acid residue. The antibodies produced according to the present method are useful as immunofluorescent markers to enumerate circulating red blood cells which have the property of altered expression of the hemoglobin gene due to somatic mutation in stem cells. Such a measurement is contemplated as an assay for in vivo cellular somatic mutations in humans. Since the monoclonal antibodies produced in accordance with the instant invention exhibit a high degree of specificity to and greater affinity for hemoglobin S, they are suitable for labeling human red blood cells for flow cytometric detection of hemoglobin genotype.

  4. Modeling hemoglobin at optical frequency using the unconditionally stable fundamental ADI-FDTD method.

    PubMed

    Heh, Ding Yu; Tan, Eng Leong

    2011-04-12

    This paper presents the modeling of hemoglobin at optical frequency (250 nm - 1000 nm) using the unconditionally stable fundamental alternating-direction-implicit finite-difference time-domain (FADI-FDTD) method. An accurate model based on complex conjugate pole-residue pairs is proposed to model the complex permittivity of hemoglobin at optical frequency. Two hemoglobin concentrations at 15 g/dL and 33 g/dL are considered. The model is then incorporated into the FADI-FDTD method for solving electromagnetic problems involving interaction of light with hemoglobin. The computation of transmission and reflection coefficients of a half space hemoglobin medium using the FADI-FDTD validates the accuracy of our model and method. The specific absorption rate (SAR) distribution of human capillary at optical frequency is also shown. While maintaining accuracy, the unconditionally stable FADI-FDTD method exhibits high efficiency in modeling hemoglobin.

  5. Electron Transfer Dissociation Mass Spectrometry of Hemoglobin on Clinical Samples

    NASA Astrophysics Data System (ADS)

    Coelho Graça, Didia; Lescuyer, Pierre; Clerici, Lorella; Tsybin, Yury O.; Hartmer, Ralf; Meyer, Markus; Samii, Kaveh; Hochstrasser, Denis F.; Scherl, Alexander

    2012-10-01

    A mass spectrometry-based assay combining the specificity of selected reaction monitoring and the protein ion activation capabilities of electron transfer dissociation was developed and employed for the rapid identification of hemoglobin variants from whole blood without previous proteolytic cleavage. The analysis was performed in a robust ion trap mass spectrometer operating at nominal mass accuracy and resolution. Subtle differences in globin sequences, resulting with mass shifts of about one Da, can be unambiguously identified. These results suggest that mass spectrometry analysis of entire proteins using electron transfer dissociation can be employed on clinical samples in a workflow compatible with diagnostic applications.

  6. Computation of the unsteady facilitated transport of oxygen in hemoglobin

    NASA Technical Reports Server (NTRS)

    Davis, Sanford

    1990-01-01

    The transport of a reacting permeant diffusing through a thin membrane is extended to more realistic dissociation models. A new nonlinear analysis of the reaction-diffusion equations, using implicit finite-difference methods and direct block solvers, is used to study the limits of linearized and equilibrium theories. Computed curves of molecular oxygen permeating through hemoglobin solution are used to illustrate higher-order reaction models, the effect of concentration boundary layers at the membrane interfaces, and the transient buildup of oxygen flux.

  7. Carbon monoxide binding to a fish hemoglobin under photostationary conditions.

    PubMed

    Torkelson, S J; Gibson, Q H

    1978-10-25

    Determinations of carbon monoxide binding curves for hemoglobin from Brevoortia tyrannus under equilibrium and photostationary conditions show that in the light, the curve is shifted to the right and altered in shape. The Bohr effect is much less in the light. The kinetics of the transition between equilibrium and photostationary states has been examined. All of the results are satisfactorily described using the two-state model of Monod, J. Wyman, J., and Changeux, J.P. (1965) J. Mol. Biol. 12, 88-118 with the assumption that light produces an additive increase in the rate of dissociation of ligand from the R and T states. PMID:701255

  8. Broadband diffuse optical spectroscopy assessment of hemorrhage- and hemoglobin-based blood substitute resuscitation

    NASA Astrophysics Data System (ADS)

    Lee, Jangwoen; Kim, Jae G.; Mahon, Sari; Tromberg, Bruce J.; Mukai, David; Kreuter, Kelly; Saltzman, Darin; Patino, Renee; Goldberg, Robert; Brenner, Matthew

    2009-07-01

    Hemoglobin-based oxygen carriers (HBOCs) are solutions of cell-free hemoglobin (Hb) that have been developed for replacement or augmentation of blood transfusion. It is important to monitor in vivo tissue hemoglobin content, total tissue hemoglobin [THb], oxy- and deoxy-hemoglobin concentrations ([OHb], [RHb]), and tissue oxygen saturation (StO2=[OHb]/[THb]×100%) to evaluate effectiveness of HBOC transfusion. We designed and constructed a broadband diffuse optical spectroscopy (DOS) prototype system to measure bulk tissue absorption and scattering spectra between 650 and 1000 nm capable of accurately determining these tissue hemoglobin component concentrations in vivo. Our purpose was to assess the feasibility of using DOS to optically monitor tissue [OHb], [RHb], StO2, and total tissue hemoglobin concentration ([THb]=[OHb]+[RHb]) during HBOC infusion using a rabbit hypovolemic shock model. The DOS prototype probe was placed on the shaved inner thigh muscle of the hind leg to assess concentrations of [OHb], [RHb], [THb], as well as StO2. Hemorrhagic shock was induced in intubated New Zealand white rabbits (N=6) by withdrawing blood via a femoral arterial line to 20% blood loss (10-15 cc/kg). Hemoglobin glutamer-200 (Hb-200) 1:1 volume resuscitation was administered following the hemorrhage. These values were compared against traditional invasive measurements, serum hemoglobin concentration (sHGB), systemic blood pressure, heart rate, and blood gases. DOS revealed increases of [THb], [OHb], and tissue hemoglobin oxygen saturation after Hb-200 infusion, while blood total hemoglobin values continued did not increase; we speculate, due to hyperosmolality induced hemodilution. DOS enables noninvasive in vivo monitoring of tissue hemoglobin and oxygenation parameters during shock and volume expansion with HBOC and potentially enables the assessment of efficacy of resuscitation efforts using artificial blood substitutes.

  9. Genetic and developmental variation of hemoglobin in the deermouse, Peromyscus maniculatus.

    PubMed

    Maybank, K M; Dawson, W D

    1976-04-01

    A genetic investigation of electrophoretic hemoglobin variants of the deermouse, Peromyscus maniculatus, shows three alleles, Hblf, Hblr, and Hblo, at a duplicated site controlling the six adult phenotypes. The Hblf allele has not been described previously. The hemoglobin locus is not closely linked to the albino locus. Fetal hemoglobin is distinct from any of the adult components and has a slower electrophoretic mobility. The fetal phenotype changes to the adult type between the days 15 and 18 of prenatal life. PMID:962849

  10. Oxidative stress in preeclampsia and the role of free fetal hemoglobin

    PubMed Central

    Hansson, Stefan R.; Nääv, Åsa; Erlandsson, Lena

    2015-01-01

    Preeclampsia is a leading cause of pregnancy complications and affects 3–7% of pregnant women. This review summarizes the current knowledge of a new potential etiology of the disease, with a special focus on hemoglobin-induced oxidative stress. Furthermore, we also suggest hemoglobin as a potential target for therapy. Gene and protein profiling studies have shown increased expression and accumulation of free fetal hemoglobin in the preeclamptic placenta. Predominantly due to oxidative damage to the placental barrier, fetal hemoglobin leaks over to the maternal circulation. Free hemoglobin and its metabolites are toxic in several ways; (a) ferrous hemoglobin (Fe2+) binds strongly to the vasodilator nitric oxide (NO) and reduces the availability of free NO, which results in vasoconstriction, (b) hemoglobin (Fe2+) with bound oxygen spontaneously generates free oxygen radicals, and (c) the heme groups create an inflammatory response by inducing activation of neutrophils and cytokine production. The endogenous protein α1-microglobulin, with radical and heme binding properties, has shown both ex vivo and in vivo to have the ability to counteract free hemoglobin-induced placental and kidney damage. Oxidative stress in general, and more specifically fetal hemoglobin-induced oxidative stress, could play a key role in the pathology of preeclampsia seen both in the placenta and ultimately in the maternal endothelium. PMID:25628568

  11. An “acquired” hemoglobin J variant in a sickle cell disease patient

    PubMed Central

    Swedan, Nawwar; Nicol, Kathleen; Moder, Phylis; Kahwash, Samir

    2008-01-01

    We report the case of a rare hemoglobin variant, “Hemoglobin J”, discovered while performing hemoglobin electrophoresis following exchange transfusion of a sickle cell disease patient. It is usual practice in our institution to confirm the hemoglobin S level in sickle cell disease patients after red cell exchange. The patient had received 5 red cell units and the source of this variant was traced back to two of those units. Due to the uncertain clinical impact of this variant, and the lack of specific guidelines, the two donors were deferred from future donations to our institution. PMID:18827863

  12. Molecular analysis of the high-hemoglobin-F phenotype in Saudi Arabian sickle cell anemia.

    PubMed

    Miller, B A; Olivieri, N; Salameh, M; Ahmed, M; Antognetti, G; Huisman, T H; Nathan, D G; Orkin, S H

    1987-01-29

    Patients from the eastern province of Saudi Arabia who have sickle cell anemia have high circulating levels of fetal hemoglobin (hemoglobin F, 17 percent), and they therefore have a mild form of the disease. To examine the molecular basis of the elevated production of hemoglobin F, we searched for mutations in the promoter regions of the two hemoglobin F gamma-globin genes (G gamma and A gamma). The DNA sequences 450 bp (base pairs) upstream of both the G gamma and A gamma globin genes were normal except for a single-base cytosine-to-thymidine (C----T) substitution at -158 bp 5' to the cap (preinitiation) site of the G gamma-globin gene of the high-hemoglobin-F chromosome. We searched for an association between this -158 C----T substitution and the production of hemoglobin F and G gamma in normal Saudis and Saudis with sickle cell disease or trait. The substitution was present in nearly 100 percent of the patients with sickle cell disease or trait, and in 22 percent of the normal Saudis. Homozygosity for this mutation had no demonstrable effect on hemoglobin F production in the normal Saudi population. We conclude that this mutation is not uniquely responsible for the increase in hemoglobin F in Saudi patients. It may nevertheless have an important role in regulating hemoglobin F production, but its expression is complex and requires interaction with additional factors, such as hemolytic stress or other molecular determinants, possibly linked to the sickle cell gene.

  13. The temperature dependence of refractive index of hemoglobin at the wavelengths 930 and 1100 nm

    NASA Astrophysics Data System (ADS)

    Lazareva, Ekaterina N.; Tuchin, Valery V.

    2016-04-01

    In this study, the refractive index of hemoglobin was measured at different temperatures within a physiological range and above that is characteristic to light-blood interaction at laser therapy. Measurements were carried out using the multi-wavelength Abbe refractometer (Atago, Japan). The refractive index was measured at two NIR wavelengths of 930 nm and 1100 nm. Samples of hemoglobin solutions with concentration of 80, 120 and 160 g/l were investigated. The temperature was varied between 25 and 55 °C. It was shown that the dependence of the refractive index of hemoglobin is nonlinear with temperature, which may be associated with changes in molecular structure of hemoglobin.

  14. The crystal structure of oxy hemoglobin from high oxygen affinity bird emu (Dromaius novaehollandiae).

    PubMed

    Mohamed Abubakkar, Mohamed H; Saraboji, Kadhirvel; Ponnuswamy, Mon Nanjappa G

    2014-01-01

    Hemoglobin is an honorary enzyme, a two-way respiratory carrier, transporting oxygen from the lungs to the tissues and facilitating the return transport of carbon dioxide. Hemoglobin has high affinity for oxygen and low affinity for carbon dioxide and other substances in the arterial circulation, whereas in the venous circulation these relative affinities are upturned. The oxygen affinity of hemoglobin increases with the fall in temperature and decreases with the increase in pH and 2, 3-bisphosphoglycerate; point mutations also affect the tetrameric arrangement and alter the oxygen affinity. Though several studies have revealed the specific reasons for the adaptation of increased oxygen affinity of avian hemoglobins at high-altitudes, further structural insights on hemoglobins from high oxygen affinity species are required to understand the detailed oxygen adaptation at the molecular level. Herein, we describe the structural investigation of hemoglobin from emu (Dromaius novaehollandiae), a high oxygen affinity bird. Hemoglobin from emu was purified using anion-exchange chromatography, crystallized and determined the structure in the oxy form at a resolution of 2.3 Å; the R-factor of the model was 19.2%. The structure was compared with other oxy hemoglobins of high oxygen affinity avian species; significant changes are noted at intra-subunit contacts which provide the clues for increased oxygen affinity of emu hemoglobin. PMID:25146185

  15. Hemoglobin aggregates studied under static and dynamic conditions involving the formation of nanobacteria-like structures.

    PubMed

    Baum, Jeramy L R; Jones, Riland L; Manning, Thomas J; Nienow, James; Phillips, Dennis

    2012-06-01

    Laser light scattering and scanning electron microscopy (SEM) are used to study hemoglobin in the aqueous phase. The impact that salts [NaCl, Ca₃(PO₄)₂] and iron oxide nanoparticles have on the hemoglobin size are also studied. The first set of experiments examined hemoglobin aggregates in the aqueous phases in the presence of salts and nanoparticles. Aqueous phase samples were then dehydrated and examined using SEM. The resulting structures resemble those observed in nanobacteria studies conducted in other labs. This study demonstrates that aggregates of hemoglobin and various salts found in a physiological environment can produce structures that resemble nanobacteria. PMID:22750818

  16. Structural and redox behavior of OxyVita, a zero-linked polymeric hemoglobin: comparison with natural acellular polymeric hemoglobins.

    PubMed

    Harrington, John P; Orlik, Kseniya; Orlig, Kseniya; Zito, Samantha L; Wollocko, Jacek; Wollocko, Hanna

    2010-04-01

    A zero-linked polymeric hemoglobin (OxyVita Hb) has been developed for application as an acellular therapeutic hemoglobin-based-oxygen-carrier (HBOC). For effective and safe oxygen binding, transport and delivery, an HBOC must meet essential molecular requirements related to its structural integrity and redox stability. OxyVita is a super polymer possessing an average M.wt. of 17 x 10(6) Da. Structural integrity was determined by unfolding studies of OxyVita in the presence of increasing concentrations of urea. The unfolding midpoints (D(1/2)) of different preparations of OxyVita (solution and powder forms) were compared to Lumbricus Hb (LtHb) and Arenicola Hb (ArHb), natural acellular polymeric hemoglobins, which are serving as models for an effective and safe acellular HBOC. Reduction studies of OxyVita Hb using endogenous reducing agents were also investigated. Results from these studies indicate that: 1) OxyVita Hb exhibits greater resistance to conformational change than either LtHb or ArHb in the reduced (oxyHb) state; and 2) the reduction of met OxyVita Hb to oxyHb occurs slowly in the presence of either ascorbic acid (70% reduction in 560 min.) or beta-NADH (40% reduction in 90 min.). These studies provide consistent evidence that OxyVita Hb possesses physiochemical properties that exhibit structural integrity and redox behavior necessary for functioning as an effective and safe HBOC within clinical applications. These results are in agreement with observations made by other investigators as to the reduction in heme-loss of OxyVita Hb, essential for the reversible binding/release of molecular oxygen within the circulatory system. PMID:20196683

  17. Structural and redox behavior of OxyVita, a zero-linked polymeric hemoglobin: comparison with natural acellular polymeric hemoglobins.

    PubMed

    Harrington, John P; Orlik, Kseniya; Orlig, Kseniya; Zito, Samantha L; Wollocko, Jacek; Wollocko, Hanna

    2010-04-01

    A zero-linked polymeric hemoglobin (OxyVita Hb) has been developed for application as an acellular therapeutic hemoglobin-based-oxygen-carrier (HBOC). For effective and safe oxygen binding, transport and delivery, an HBOC must meet essential molecular requirements related to its structural integrity and redox stability. OxyVita is a super polymer possessing an average M.wt. of 17 x 10(6) Da. Structural integrity was determined by unfolding studies of OxyVita in the presence of increasing concentrations of urea. The unfolding midpoints (D(1/2)) of different preparations of OxyVita (solution and powder forms) were compared to Lumbricus Hb (LtHb) and Arenicola Hb (ArHb), natural acellular polymeric hemoglobins, which are serving as models for an effective and safe acellular HBOC. Reduction studies of OxyVita Hb using endogenous reducing agents were also investigated. Results from these studies indicate that: 1) OxyVita Hb exhibits greater resistance to conformational change than either LtHb or ArHb in the reduced (oxyHb) state; and 2) the reduction of met OxyVita Hb to oxyHb occurs slowly in the presence of either ascorbic acid (70% reduction in 560 min.) or beta-NADH (40% reduction in 90 min.). These studies provide consistent evidence that OxyVita Hb possesses physiochemical properties that exhibit structural integrity and redox behavior necessary for functioning as an effective and safe HBOC within clinical applications. These results are in agreement with observations made by other investigators as to the reduction in heme-loss of OxyVita Hb, essential for the reversible binding/release of molecular oxygen within the circulatory system.

  18. Tyrosine can protect against oxidative stress through ferryl hemoglobin reduction.

    PubMed

    Lu, Naihao; He, Yingjie; Chen, Chao; Tian, Rong; Xiao, Qiang; Peng, Yi-Yuan

    2014-08-01

    The toxic mechanism of hemoglobin (Hb) under oxidative stress is linked to the formations of highly cytotoxic ferryl species and subsequently heme-to-protein cross-linked derivative of Hb (Hb-X). In this study, we have examined the effects of free tyrosine and its analogues (3-chlorotyrosine, phenylalanine) on the stability of ferryl hemoglobin and the formation of Hb-X. The results showed that free tyrosine (not phenylalanine, 10-500 μM) was an efficient reducing agent of ferryl species and also effective at preventing the formation of cytotoxic Hb-X. Meanwhile, the dimeric tyrosine was formed as the oxidation product of tyrosine during Hb redox reaction. Compared with free tyrosine, 3-chlorotyrosine, an oxidation product of tyrosine and a proposed biomarker for hypochlorous acid (HOCl) in vivo, exhibited stronger antioxidant properties in Hb-induced oxidative stress, which was consistent with its more efficient ability in the reduction of ferryl species. These results showed that the presence of tyrosine and its derivative in vivo and vitro could ameliorate oxidative damage through ferryl heme reduction. The antioxidant ability, therefore, may provide new insights into the nutritional and physiological significance of free tyrosine with redox active heme proteins-related oxidative stress.

  19. Effectors of hemoglobin. Separation of allosteric and affinity factors.

    PubMed Central

    Marden, M C; Bohn, B; Kister, J; Poyart, C

    1990-01-01

    The relative contributions of the allosteric and affinity factors toward the change in p50 have been calculated for a series of effectors of hemoglobin (Hb). Shifts in the ligand affinity of deoxy Hb and the values for 50% ligand saturation (p50) were obtained from oxygen equilibrium data. Because the high-affinity parameters (liganded conformation) are poorly determined from the equilibrium curves, they were determined from kinetic measurements of the association and dissociation rates with CO as ligand. The CO on-rates were obtained by flash photolysis measurements. The off-rates were determined from the rate of oxidation of HbCO by ferricyanide, or by replacement of CO with NO. The partition function of fully liganded hemoglobin for oxygen and CO is only slightly changed by the effectors. Measurements were made in the presence of the effectors 2,3-diphosphoglycerate (DPG), inositol hexakisphosphate (IHP), bezafibrate (Bzf), and two recently synthesized derivatives of Bzf (LR16 and L35). Values of p50 change by over a factor of 60; the on-rates decrease by nearly a factor of 8, with little change in the off-rates for the liganded conformation. The data indicate that both allosteric and affinity parameters are changed by the effectors; the changes in ligand affinity represent the larger contribution toward shifts in p50. PMID:2306490

  20. Multiwavelength pulse oximetry in the measurement of hemoglobin fractions

    NASA Astrophysics Data System (ADS)

    Manzke, Bernd; Schwider, Johannes; Lutter, Norbert O.; Engelhardt, Kai; Stork, Wilhelm

    1996-04-01

    The two wavelength design of the majority of pulse oximeters assumes only two absorbing hemoglobin fractions, oxyhemoglobin (O2Hb), and reduced hemoglobin (HHb) irrespective of the presence of methemoglobin (MetHb) and carboxyhemoglobin (COHb). If MetHb or COHb is present, it contributes to the pulse-added absorbance signal and will be interpreted as either HHb or O2Hb or some combination of the two. In this paper we describe a noninvasive multi-wavelength pulse oximeter measuring O2Hb, HHb, MetHb, and COHb at a specified accuracy of 1.0%. The system was designed with respect to the results of numerical simulations. It consists of 9 laserdiodes (LDs) and 7 light emitting diodes (LEDs), a 16-bit analog-digital converter (ADC) and has a sampling rate of 16 kHz. The laser didoes and LEDs were coupled into multi-mode fibers and led with a liquid lightguide to the finger clip and then the photodiode. It also presents the results of a clinical study, including a setup with a quartz tungsten halogen lamp (with fiber output) and a diode array spectrometer, a standard pulse oximeter and two in-vitro oximeters (radiometer OSM3 and radiometer ABL 520) as references.

  1. Autofluorescence characterization of advanced glycation end products of hemoglobin

    NASA Astrophysics Data System (ADS)

    Vigneshwaran, Nadanathangam; Bijukumar, Gopalakrishnapillai; Karmakar, Nivedita; Anand, Sneh; Misra, Anoop

    2005-01-01

    This article describes the analysis of autofluorescence of advanced glycation end products of hemoglobin (Hb-AGE). Formed as a result of slow, spontaneous and non-enzymatic glycation reactions, Hb-AGE possesses a characteristic autofluorescence at 308/345 nm ( λex/ λem). Even in the presence of heme as a quenching molecule, the surface presence of the glycated adduct gave rise to autofluorescence with the quantum yield of 0.19. The specificity of monoclonal antibody developed against common AGE structure with Hb-AGE was demonstrated using reduction in fluorescence polarization value due to increased molecular volume while binding. The formation of fluorescent adduct in hemoglobin in the advanced stage of glycation and the non-fluorescent HbA 1c will be of major use in distinguishing and to know the past status of diabetes mellitus. While autofluorescence correlated highly with HbA 1c value under in vivo condition ( r=0.85), it was moderate in the clinical samples ( r=0.55). The results suggest a non-linear relation between glycemia and glycation, indicating the application of Hb-AGE as a measure of susceptibility to glycation rather than glycation itself.

  2. Carnivora: primary structure of the hemoglobins from ratel (Mellivora capensis).

    PubMed

    Rodewald, K; Braunitzer, G; Göltenboth, R

    1988-10-01

    The erythrocytes of adult ratel contain two hemoglobin components, with two alpha- and one beta-chains. In this paper, their complete amino acid sequences are presented. The two alpha-chains differ in one residue at position 34 (Ala----Val) only. The primary structure of the chains was determined by sequencing the N-terminal regions (45 steps) and the tryptic peptides after their isolation from the digests by reversed-phase high-performance liquid chromatography. The alignment of these peptides was deduced from homology with other carnivora globins. The alpha-chains show 21 and the beta-chains 11 exchanges compared with human globin chains. In the alpha-chains, one heme- and two alpha 1/beta 1 contacts are exchanged. In the beta-chains there are three exchanges which involve one alpha 1/beta 1-, one alpha 1/beta 2- and one heme-contact. Between the ratel hemoglobin and those of carnivora a high degree of homology was found. PMID:3242544

  3. Screening for Structural Hemoglobin Variants in Bahia, Brazil

    PubMed Central

    Silva, Wellington Santos; de Oliveira, Roberto Ferreira; Ribeiro, Sanzia Bezerra; da Silva, Isabel Batista; de Araújo, Edna Maria; Baptista, Abrahão Fontes

    2016-01-01

    Brazil was the country that received the largest number of Africans during the time of colonization, and Bahia was the Brazilian state that received the largest number of slaves from Africa. The purpose of this study was to evaluate the coverage of the newborn screening program for sickle cell disease in the Recôncavo Baiano region of the state of Bahia, and to show the frequency of the subjects with hemoglobin variants in the 2006–2009 period. Blood samples from neonates in twelve cities in the Recôncavo Baiano region were analyzed by High Performance Liquid Chromatography. A total of 16,402 children were born in this period, 14,773 of which underwent newborn screening. In this period 1416 children were born carrying hemoglobin variants HbS and HbC. Forty-seven patients—20 HbSS genotype and 27 HbSC genotype—were diagnosed in eleven of the twelve cities surveyed. The proportion of children born with sickle cell disease in the Recôncavo Baiano region was 1/314, which was higher than the 1/650 rate for the state of Bahia. The data presented in this study confirm the high frequency of sickle cell disease in Recôncavo Baiano, demonstrating the need to create a referral center for the care of patients with sickle cell diseases in the region. PMID:26901212

  4. Vitreoscilla hemoglobin gene ( vgb) improves lutein production in Chlorella vulgaris

    NASA Astrophysics Data System (ADS)

    Ma, Ruijuan; Lin, Xiangzhi

    2014-03-01

    Vitreoscilla hemoglobin is an oxygen-binding protein that promotes oxygen delivery and reduces oxygen consumption under low oxygen conditions to increase the efficiency of cell respiration and metabolism. In this study, we introduced a Vitreoscilla hemoglobin gene ( vgb) into Chlorella vulgaris by Agrobacterium tumefaciens -mediated transformation (ATMT). PCR analysis confirmed that the vgb gene was successfully integrated into the Chlorella vulgaris genome. Analysis of biomass obtained in shake flasks revealed transformant biomass concentrations as high as 3.28 g/L, which was 38.81% higher than that of the wild-type strain. Lutein content of transformants also increased slightly. Further experiments recovered a maximum lutein yield of 2.91 mg/L from the transformants, which was 36.77% higher than that of the wild-type strain. The above results suggest that integrated expression of the vgb gene may improve cell growth and lutein yield in Chlorella vulgaris, with applications to lutein production from Chlorella during fermentation.

  5. Biphasic Oxidation of Oxy-Hemoglobin in Bloodstains

    PubMed Central

    Bremmer, Rolf H.; de Bruin, Daniel M.; de Joode, Maarten; Buma, Wybren Jan; van Leeuwen, Ton G.; Aalders, Maurice C. G.

    2011-01-01

    Background In forensic science, age determination of bloodstains can be crucial in reconstructing crimes. Upon exiting the body, bloodstains transit from bright red to dark brown, which is attributed to oxidation of oxy-hemoglobin (HbO2) to met-hemoglobin (met-Hb) and hemichrome (HC). The fractions of HbO2, met-Hb and HC in a bloodstain can be used for age determination of bloodstains. In this study, we further analyze the conversion of HbO2 to met-Hb and HC, and determine the effect of temperature and humidity on the conversion rates. Methodology The fractions of HbO2, met-Hb and HC in a bloodstain, as determined by quantitative analysis of optical reflectance spectra (450–800 nm), were measured as function of age, temperature and humidity. Additionally, Optical Coherence Tomography around 1300 nm was used to confirm quantitative spectral analysis approach. Conclusions The oxidation rate of HbO2 in bloodstains is biphasic. At first, the oxidation of HbO2 is rapid, but slows down after a few hours. These oxidation rates are strongly temperature dependent. However, the oxidation of HbO2 seems to be independent of humidity, whereas the transition of met-Hb into HC strongly depends on humidity. Knowledge of these decay rates is indispensable for translating laboratory results into forensic practice, and to enable bloodstain age determination on the crime scene. PMID:21789186

  6. Stability of blood carbon monoxide and hemoglobins during heating.

    PubMed

    Seto, Y; Kataoka, M; Tsuge, K

    2001-09-15

    The effects of heating on hemoglobin (Hb) and carbon monoxide (CO) levels in human blood were investigated by in vitro experiments. Head-space gas chromatography (HS-GC) using a molecular sieve 5A stationary phase and thermal conductivity detection was adopted for the measurement of CO gas, and spectrophotometric methods were used for the measurement of various Hb forms, protein and heme contents. Deteriorated absorbance spectra were observed for heat-treated blood samples, and double wavelength spectrophotometry was proven to give wrong percent saturation of carboxyhemoglobin content (% CO-Hb). The blood sample taken from one fatal fire casualty gave significantly higher % CO-Hb measured spectrophotometrically, compared to that by HS-GC. Control blood or purified Hb solution, which was saturated with CO in designated extent, was heated in a sealed vial. Under the incubation below 54 degrees C, all Hb forms were stable, except for oxyhemoglobin (Hb-O(2)), which was partially oxidized to met-hemoglobin (Met-Hb). In contrast, under the incubation at 65 degrees C, Met-Hb was denatured completely to be insoluble, and Hb-O(2) was partially denatured via Met-Hb formation. CO-Hb was resistant against heating. The difference of heat susceptibility and precipitability among Hb forms resulted in artificial increase of % CO-Hb. During heating, spontaneous CO was produced from blood.

  7. [Hemoglobin and testosterone: importance on high altitude acclimatization and adaptation].

    PubMed

    Gonzales, Gustavo F

    2011-03-01

    The different types of response mechanisms that the organism uses when exposed to hypoxia include accommodation, acclimatization and adaptation. Accommodation is the initial response to acute exposure to high altitude hypoxia and is characterized by an increase in ventilation and heart rate. Acclimatization is observed in individuals temporarily exposed to high altitude, and to some extent, it enables them to tolerate the high altitudes. In this phase, erythropoiesis is increased, resulting in higher hemoglobin and hematocrit levels to improve oxygen delivery capacity. Adaptation is the process of natural acclimatization where genetical variations and acclimatization play a role in allowing subjects to live without any difficulties at high altitudes. Testosterone is a hormone that regulates erythropoiesis and ventilation and could be associated to the processes of acclimatization and adaptation to high altitude. Excessive erythrocytosis, which leads to chronic mountain sickness, is caused by low arterial oxygen saturation, ventilatory inefficiency and reduced ventilatory response to hypoxia. Testosterone increases during acute exposure to high altitude and also in natives at high altitude with excessive erythrocytosis. Results of current research allow us to conclude that increase in serum testosterone and hemoglobin is adequate for acclimatization, as they improve oxygen transport, but not for high altitude adaptation, since high serum testosterone levels are associated to excessive erythrocytosis.

  8. Redox reactions of hemoglobin: mechanisms of toxicity and control.

    PubMed

    Mollan, Todd L; Alayash, Abdu I

    2013-06-10

    In the last several years, significant work has been done studying hemoglobin (Hb) oxidative reactions and clearance mechanisms using both in vitro and in vivo model systems. One active research area involves the study of molecular chaperones and other proteins that are thought to mitigate the toxicity of acellular Hb. For example, the plasma protein haptoglobin (Hp) and the pre-erythroid protein alpha-hemoglobin-stabilizing protein (AHSP) bind to acellular Hb and alpha-subunits of Hb, respectively, to reduce these adverse effects. Moreover, there has been significant work studying hemopexin and alpha-1 microglobulin, both of which are thought to be involved with hemin degradation. These studies have coincided with the timely publication of the first crystal structure of the Hb-Hp complex. In constructing this Forum, we have invited a number of researchers in the area of Hb and myoglobin (Mb) redox biochemistry, as well as those who have contributed fundamentally to our knowledge of Hp function. Our goal has been to update this critically important research area, because we believe that it will ultimately impact the practice of transfusion medicine in a number of important ways.

  9. Interaction of recombinant octameric hemoglobin with endothelial cells.

    PubMed

    Gaucher, Caroline; Domingues-Hamdi, Élisa; Prin-Mathieu, Christine; Menu, Patrick; Baudin-Creuza, Véronique

    2015-02-01

    Hemoglobin-based oxygen carriers (HBOCs) may generate oxidative stress, vasoconstriction and inflammation. To reduce these undesirable vasoactive properties, we increased hemoglobin (Hb) molecular size by genetic engineering with octameric Hb, recombinant (r) HbβG83C. We investigate the potential side effects of rHbβG83C on endothelial cells. The rHbβG83C has no impact on cell viability, and induces a huge repression of endothelial nitric oxide synthase gene transcription, a marker of vasomotion. No induction of Intermolecular-Adhesion Molecule 1 and E-selectin (inflammatory markers) transcription was seen. In the presence of rHbβG83C, the transcription of heme oxygenase-1 (oxidative stress marker) is weakly increased compared to the two other HBOCs (references) or Voluven (control). This genetically engineered octameric Hb, based on a human Hb βG83C mutant, leads to little impact at the level of endothelial cell inflammatory response and thus appears as an interesting molecule for HBOC development.

  10. Electrophoretic analysis of PEGylated hemoglobin-based blood substitutes.

    PubMed

    Ronda, Luca; Pioselli, Barbara; Bruno, Stefano; Faggiano, Serena; Mozzarelli, Andrea

    2011-01-01

    Polyethylene glycol (PEG)-conjugated hemoglobins, a novel class of blood substitutes, were investigated by a combination of native and denaturing one- and two-dimensional polyacrylamide gel electrophoresis (PAGE) coupled with the microspectrophotometric characterization of single bands and the functional analysis of electrophoretically separated fractions. For these intrinsically heterogeneous products, the molecular mass, the size distribution, and the degree of PEGylation are strictly correlated to their side effects and, therefore, are crucial pieces of information to evaluate their safety and efficacy. The PEGylation pattern was shown to strongly depend on the quaternary conformation of hemoglobin during the reaction, and the degree of conjugation was shown to correlate with the oxygen binding properties of the individual electrophoretically separated fractions. Moreover, small but not negligible fractions of underivatized tetramers, known to be responsible for serious side effects, were detected even in preparations with a high average degree of PEGylation. Overall, this approach might be exploited to characterize other products of protein PEGylation, an increasingly relevant technology for the optimization of the pharmacokinetic properties of protein-based drugs.

  11. Light Scattering and Absorption Studies of Sickle Cell Hemoglobin

    NASA Astrophysics Data System (ADS)

    Kim-Shapiro, Daniel

    1997-11-01

    The use of physical techniques has been very important in understanding the pathophysiology of sickle cell disease. In particular, light scattering and absorption studies have been used to measure the kinetics of sickle cell hemoglobin polymerization and depolymerization (melting). The theory of sickle cell polymerization that has been derived and tested by these methods has not only led to an increased understanding of the pathophysiology of the disease but has also led to improved treatment strategies. Sickle cell disease effects about 1 out of 600 people of African descent born in the United States. The disease is caused by a mutant form of hemoglobin (the oxygen transporting molecule in the blood), hemoglobin S (HbS), which differs from normal adult hemoglobin by the substitution of a single amino acid for another. The polymerization of HbS, which occurs under conditions of low oxygen pressure, causes distortion and increased rigidity of the sickle red blood cell that leads to blockage of the capillaries and a host of resulting complications. The disease is associated with tissue damage, severe painful crises and a high degree of mortality. Light scattering studies of purified HbS and whole cells (conducted by F.A. Ferrone, J. Hofrichter, W.A. Eaton, and their associates) have been used to determine the mechanism of HbS polymerization. Polymerization will generally not occur when the hemoglobin is in an oxygen-rich environment. The question is, when HbS is rapidly deoxygenated (as it is when going from the lungs to the tissues) what is the kinetics of polymerization? Photolysis methods were used to rapidly deoxygenate HbS and light scattering was used as a function of time to measure the kinetics of polymerization. Polarized light scattering may be a more effective way to measure polymer content than total intensity light scattering. It was found that no polymerization occurs during a period of time called the delay time and subsequent polymerization occurs

  12. Effects of Hemoglobin Variants on Hemoglobin A1c Values Measured Using a High-Performance Liquid Chromatography Method

    PubMed Central

    De-La-Iglesia, Silvia; Ropero, Paloma; Nogueira-Salgueiro, Patricia; Santana-Benitez, Jesus

    2014-01-01

    Hemoglobin A1c (HbA1c) is routinely used to monitor long-term glycemic control and for diagnosing diabetes mellitus. However, hemoglobin (Hb) gene variants/modifications can affect the accuracy of some methods. The potential effect of Hb variants on HbA1c measurements was investigated using a high-performance liquid chromatography (HPLC) method compared with an immunoturbimetric assay. Fasting plasma glucose (FPG) and HbA1c levels were measured in 42 371 blood samples. Samples producing abnormal chromatograms were further analyzed to characterize any Hb variants. Fructosamine levels were determined in place of HbA1c levels when unstable Hb variants were identified. Abnormal HPLC chromatograms were obtained for 160 of 42 371 samples. In 26 samples HbS was identified and HbA1c results correlated with FPG. In the remaining 134 samples HbD, Hb Louisville, Hb Las Palmas, Hb N-Baltimore, or Hb Porto Alegre were identified and HbA1c did not correlate with FPG. These samples were retested using an immunoturbidimetric assay and the majority of results were accurate; only 3 (with the unstable Hb Louisville trait) gave aberrant HbA1c results. Hb variants can affect determination of HbA1c levels with some methods. Laboratories should be aware of Hb variants occurring locally and choose an appropriate HbA1c testing method. PMID:25355712

  13. A cis-proline in alpha-hemoglobin stabilizing protein directs the structural reorganization of alpha-hemoglobin.

    PubMed

    Gell, David A; Feng, Liang; Zhou, Suiping; Jeffrey, Philip D; Bendak, Katerina; Gow, Andrew; Weiss, Mitchell J; Shi, Yigong; Mackay, Joel P

    2009-10-23

    alpha-Hemoglobin (alphaHb) stabilizing protein (AHSP) is expressed in erythropoietic tissues as an accessory factor in hemoglobin synthesis. AHSP forms a specific complex with alphaHb and suppresses the heme-catalyzed evolution of reactive oxygen species by converting alphaHb to a conformation in which the heme is coordinated at both axial positions by histidine side chains (bis-histidyl coordination). Currently, the detailed mechanism by which AHSP induces structural changes in alphaHb has not been determined. Here, we present x-ray crystallography, NMR spectroscopy, and mutagenesis data that identify, for the first time, the importance of an evolutionarily conserved proline, Pro(30), in loop 1 of AHSP. Mutation of Pro(30) to a variety of residue types results in reduced ability to convert alphaHb. In complex with alphaHb, AHSP Pro(30) adopts a cis-peptidyl conformation and makes contact with the N terminus of helix G in alphaHb. Mutations that stabilize the cis-peptidyl conformation of free AHSP, also enhance the alphaHb conversion activity. These findings suggest that AHSP loop 1 can transmit structural changes to the heme pocket of alphaHb, and, more generally, highlight the importance of cis-peptidyl prolyl residues in defining the conformation of regulatory protein loops.

  14. A cis-Proline in α-Hemoglobin Stabilizing Protein Directs the Structural Reorganization of α-Hemoglobin*

    PubMed Central

    Gell, David A.; Feng, Liang; Zhou, Suiping; Jeffrey, Philip D.; Bendak, Katerina; Gow, Andrew; Weiss, Mitchell J.; Shi, Yigong; Mackay, Joel P.

    2009-01-01

    α-Hemoglobin (αHb) stabilizing protein (AHSP) is expressed in erythropoietic tissues as an accessory factor in hemoglobin synthesis. AHSP forms a specific complex with αHb and suppresses the heme-catalyzed evolution of reactive oxygen species by converting αHb to a conformation in which the heme is coordinated at both axial positions by histidine side chains (bis-histidyl coordination). Currently, the detailed mechanism by which AHSP induces structural changes in αHb has not been determined. Here, we present x-ray crystallography, NMR spectroscopy, and mutagenesis data that identify, for the first time, the importance of an evolutionarily conserved proline, Pro30, in loop 1 of AHSP. Mutation of Pro30 to a variety of residue types results in reduced ability to convert αHb. In complex with αHb, AHSP Pro30 adopts a cis-peptidyl conformation and makes contact with the N terminus of helix G in αHb. Mutations that stabilize the cis-peptidyl conformation of free AHSP, also enhance the αHb conversion activity. These findings suggest that AHSP loop 1 can transmit structural changes to the heme pocket of αHb, and, more generally, highlight the importance of cis-peptidyl prolyl residues in defining the conformation of regulatory protein loops. PMID:19706593

  15. Hemoglobin Aggregation in Single Red Blood Cells of Sickle Cell Anemia

    NASA Astrophysics Data System (ADS)

    Nishio, Izumi; Tanaka, Toyoichi; Sun, Shao-Tang; Imanishi, Yuri; Tsuyoshi Ohnishi, S.

    1983-06-01

    A laser light scattering technique was used to observe the extent of hemoglobin aggregation in solitary red blood cells of sickle cell anemia. Hemoglobin aggregation was confirmed in deoxygenated cells. The light scattering technique can also be applied to cytoplasmic studies of any biological cell.

  16. Effect of deep breathing on extracted oxygen and cerebral hemoglobin levels.

    PubMed

    Kennedy, Patrick M; Zarbock, Christopher M; Burke, Broc A; Diamond, Solomon G

    2011-01-01

    This study examines the relationship between oxygen expired and functional near infrared spectroscopy (fNIRS) measured hemoglobin levels in the brain. Analysis of these two signals during normal versus deep breathing provides insight into the dynamics of cerebral physiology. Intersubject variation suggests the existence of two distinct groups with respect to oxygen extraction and hemoglobin levels. PMID:22254486

  17. Molecular Cloning and Sequencing of Hemoglobin-Beta Gene of Channel Catfish, Ictalurus Punctatus Rafinesque

    Technology Transfer Automated Retrieval System (TEKTRAN)

    : Hemoglobin-y gene of channel catfish , lctalurus punctatus, was cloned and sequenced . Total RNA from head kidneys was isolated, reverse transcribed and amplified . The sequence of the channel catfish hemoglobin-y gene consists of 600 nucleotides . Analysis of the nucleotide sequence reveals one o...

  18. Using the Cascade Model to Improve Antenatal Screening for the Hemoglobin Disorders

    ERIC Educational Resources Information Center

    Gould, Dinah; Papadopoulos, Irena; Kelly, Daniel

    2012-01-01

    Introduction: The inherited hemoglobin disorders constitute a major public health problem. Facilitators (experienced hemoglobin counselors) were trained to deliver knowledge and skills to "frontline" practitioners to enable them to support parents during antenatal screening via a cascade (train-the-trainer) model. Objectives of evaluation were to…

  19. Hemoglobin oxidation products extract phospholipids from the membrane of human erythrocytes.

    PubMed

    Moxness, M S; Brunauer, L S; Huestis, W H

    1996-06-01

    Hydrogen peroxide oxidation of human erythrocytes induces a transfer of phospholipid from the membrane into the cytosol [Brunauer, L.S., Moxness, M.S., & Huestis, W.H. (1994) Biochemistry 33, 4527-4532]. The current study examines the mechanism of lipid reorganization in oxidized cells. Exogenous phosphatidylserine was introduced into the inner monolayer of erythrocytes, and its distribution was monitored by microscopy and radioisotopic labeling. Pretreatment of cells with carbon monoxide prevented both hemoglobin oxidation and the transfer of phosphatidyserine into the cytosolic compartment. The roles of the various hemoglobin oxidation products in lipid extraction were investigated using selective oxidants. Nitrite treatment of intact cells produced almost complete conversion to methemoglobin, but no detectable lipid extraction. Treatments designed to produce the green hemoglobin derivatives, sulfhemoglobin and choleglobin, resulted in cytosolic extraction of phosphatidylserine. Ion exchange and size exclusion chromatography of oxidized cytosolic components revealed a lipid-hemoglobin complex. The interaction between lipid and hemoglobin oxidation products was verified in a model system. Purified hemoglobin, enriched in sulfhemoglobin and choleglobin by treatment with H2O2, H2S, or ascorbate, extracted phospholipid from small unilamellar phospholipid vesicles. Electron paramagnetic resonance studies demonstrated that hemoglobin oxidation products also adsorb fatty acids from solution. This newly described activity of hemoglobin may play a role in the clearance of oxidatively damaged and senescent cells from circulation.

  20. Band assignment in hemoglobin porphyrin ring spectrum: using four-orbital model of Gouterman.

    PubMed

    Dayer, Mohammad Reza; Moosavi-Movahedi, Ali Akbar; Dayer, Mohammad Saaid

    2010-04-01

    Band assignment for oxy, deoxy and methemoglobin using orbital promotion is crucial to understanding inter-relation of electronic transitions. Spectral changes may be correlated with conformational alteratiions. Conformational changes of hemoglobin were interpreted using four-orbital model of Gouterman. Our results indicated that Goutherman model can predict the predominant conformations of hemoglobin.

  1. Iron bioavailability of maize hemoglobin in a Caco-2 cell culture model

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Maize is an important staple crop in many parts of the world but has low iron bioavailability, in part due to its high phytate content. Hemoglobin is a form of iron that is highly bioavailable and its bioavailability is not inhibited by phytate. We hypothesize that maize hemoglobin is a highly bioav...

  2. Prevalence of common hemoglobin variants in an afro-descendent Ecuadorian population

    PubMed Central

    2013-01-01

    Background Hemoglobinopathies are among the most studied and frequent pathologies. These genetic disorders are considered a very important health care threat in many tropical countries. Ecuador is a tropical Latin-American country with an important presence of afro-descendants (7.2%). Afro-descendants are among the ethnic groups with higher frequency of hemoglobinopathies reported. Ambuqui is a region within the Imbabura province with an important presence of afro-descendants (>50%). The present study analyzed the frequency of the most common hemoglobin variants in an asymptomatic afro-descendent population using capillary electrophoresis. Findings From 114 individuals, 25 (22%) reported a hemoglobin variant. All individuals that presented hemoglobin variants were heterozygotes (asymptomatic). Hemoglobin S (sickle cell trait) was the most frequent variant found (14%), followed by hemoglobin E (4.4%), Fetal (2.6%) and C (1%). Conclusion Prevalence of hemoglobin S was consistent with populations from other countries, but it was lower than other Ecuadorian afro-descendent populations. Frequency of hemoglobin C was lower than other afro-descendent populations. This data suggests the possibility of gene flow from Native American individuals to the Ambuqui population there by lowering the frequency of their hemoglobin variants compared with other afro-descendant populations. Evaluating the frequency of hemoglobinopathies in Ecuadorian populations is essential. Despite the high frequency of these disorders, very few health care facilities implement hemoglobinopathies tests as a routine practice. PMID:23557107

  3. A Simple Question to Think about When Considering the Hemoglobin Function

    ERIC Educational Resources Information Center

    Ruiz-Larrea, M. Begona

    2002-01-01

    Hemoglobin is a complex protein formed by various subunits interacting with each other. These noncovalent interactions, quaternary structure, are responsible for hemoglobin functioning as an excellent oxygen transporter, loading up with oxygen in the lungs and delivering it to tissues, where the oxygen pressure is lower. The communications between…

  4. Transition of hemoglobin between two tertiary conformations: The transition constant differs significantly for the major and minor hemoglobins of the Japanese quail (Cortunix cortunix japonica).

    PubMed

    Okonjo, Kehinde Onwochei; Bello, Olugbenga S; Babalola, J Oyebamiji

    2008-03-01

    We demonstrate that 5,5'-dithiobis(2-nitrobenzoate) - DTNB - reacts with only CysF9[93]beta and CysB5[23]beta among the multiple sulfhydryl groups of the major and minor hemoglobins of the Japanese quail (Cortunix cortunix japonica). K(equ), the equilibrium constant for the reaction, does not differ very significantly between the two hemoglobins. It decreases 430-fold between pH approximately 5.6 and pH approximately 9: from a mean of 7+/-1 to a mean of 0.016+/-0.003. Quantitative analyses of the K(equ) data based on published X-ray and temperature-jump evidence for a tertiary structure transition in liganded hemoglobin enable the calculation of K(rt), the equilibrium constant for the r<---->t tertiary structure transition. K(rt) differs significantly between the two hemoglobins: 0.744+/-0.04 for the major, 0.401+/-0.01 for the minor hemoglobin. The mean pK(a)s of the two groups whose ionizations are coupled to the DTNB reaction are about the same as previously reported for mammalian hemoglobins.

  5. Probing confined and unconfined hemoglobin molecules with photoacoustics

    NASA Astrophysics Data System (ADS)

    Saha, Ratan K.; Karmakar, Subhajit; Roy, Madhusudan

    2014-03-01

    Photoacoustic (PA) measurements on confined and unconfined hemoglobin molecules are presented. In vitro experiments were performed with porcine red blood cells (RBCs) at 532 and 1064 nm at various laser fluences. Fluence was gradually changed from 8 to 21 mJ/cm2/pulse for 532 nm and 353 to 643 mJ/cm2/pulse for 1064 nm. PA signals from suspended RBCs (SRBCs) and hemolyzed RBCs (HRBCs) were measured using a needle hydrophone at hematocrits ranging from 10 to 60%. PA amplitude was found to be varied linearly with the laser fluence for each type of samples at the above two optical radiations. At 532 nm, PA signals from SRBCs and HRBCs were measured to be nearly equal, whereas, at 1064 nm, signal amplitude for SRBCs was approximately 2 times higher than that of HRBCs. The results suggest that it may be feasible to detect hemolysis with PAs.

  6. Effects of Hemoglobin-Based Oxygen Carriers on Blood Coagulation

    PubMed Central

    Roghani, Kimia; Holtby, Randall J.; Jahr, Jonathan S.

    2014-01-01

    For many decades, Hemoglobin-based oxygen carriers (HBOCs) have been central in the development of resuscitation agents that might provide oxygen delivery in addition to simple volume expansion. Since 80% of the world population lives in areas where fresh blood products are not available, the application of these new solutions may prove to be highly beneficial (Kim and Greenburg 2006). Many improvements have been made to earlier generation HBOCs, but various concerns still remain, including coagulopathy, nitric oxide scavenging, platelet interference and decreased calcium concentration secondary to volume expansion (Jahr et al. 2013). This review will summarize the current challenges faced in developing HBOCs that may be used clinically, in order to guide future research efforts in the field. PMID:25514567

  7. Noninvasive hemoglobin oxygenation monitor and computed tomography by NIR spectrophotometry

    NASA Astrophysics Data System (ADS)

    Oda, Ichiro; Ito, Yasunobu; Eda, Hideo; Tamura, Tomomi; Takada, Michinosuke; Abumi, Rentaro; Nagai, Katumi; Nakagawa, Hachiro; Tamura, Masahide

    1991-05-01

    Using a near infrared (NIR) spectrophotometry, a compact instrument for monitoring the hemoglobin (Hb) oxygenation state in human brain was developed. Brian oxygen metabolism was non-invasively studied by simultaneous measurement of oxygenated Hb, deoxygnated Hb and total Hb content in rat and human head. After evaluating our method using anesthetized and artificially ventilated rats, this instrument was applied for clinical use, and was useful for the management of clinical patients. The same method was applied to develope the NIR computed tomography (CT). Human X-ray CT was modified for NIR-CT, and CT images were obtained using the back-projection (BP) method. NIR-CT could measure the oxygenation map of the tissues of anesthetized rats.

  8. Improved screening test for abnormal hemoglobins from dried blood samples.

    PubMed

    Altland, K; Kaempfer, M; Granda, H

    1979-01-01

    A method is described wherein blood samples taken from adults or newborns and dried on filter paper can be used for hemoglobin analysis within 2 years after sampling. The samples are eluted in 8 M urea in the presence of 5% 2-mercaptoethanol and 2% of the neutral detergent Nonidet P-40. Then the individual alpha, beta, gamma, and epsilon chains are separated by means of electrofocusing in 8 M urea-PAA gels. Up to 96 samples can be applied to a gel using multiple syringes. Several hundred samples can be analyzed daily by one person. This method may be especially useful for preventive programs against sickle cell anemia as well as for human mutation monitoring systems.

  9. Hemoglobin, nitric oxide and molecular mechanisms of hypoxic vasodilation

    PubMed Central

    Allen, Barry W.; Stamler, Jonathan S.; Piantadosi, Claude A.

    2009-01-01

    The protected transport of nitric oxide (NO) by hemoglobin (Hb) links the metabolic activity of working tissue to the regulation of its local blood supply through hypoxic vasodilation. This physiologic mechanism is allosterically coupled to the O2 saturation of Hb and involves the covalent binding of NO to a cysteine residue in the β-chain of Hb (Cys β93) to form S-nitrosohemoglobin (SNO-Hb). Subsequent S-transnitrosation, the transfer of NO groups to thiols on the RBC membrane and then in the plasma, preserves NO vasodilator activity for delivery to the vascular endothelium. This SNO-Hb paradigm provides insight into the respiratory cycle and a new therapeutic focus for diseases involving abnormal microcirculatory perfusion. In addition, the formation of S-nitrosothiols in other proteins may regulate an array of physiological functions. PMID:19781996

  10. Brownian dynamics simulation of sickle hemoglobin bundle formation

    NASA Astrophysics Data System (ADS)

    Liu, Ya; Gunton, James; Chakrabarti, Amit

    2010-03-01

    The physical properties of biopolymer fibers, such as their stability and degree of aggregation, are implicated in many diseases, including sickle cell anemia. The natural chirality of protofilaments plays a crucial role in the formation of sickle hemoglobin fiber which leads to the permanent blockage of microvessels. We use Brownian dynamics to investigate the kinetics of fiber aggregation. The geometrical helical structure and chirality of the filaments are modeled by anisotropic patch-like interactions. We present the kinetics of fiber formation and study the possibility of a finite critical fiber bundle size. We compare our results with various experimental and theoretical results. This work is supported by grants from the NSF and the G. Harold and Leila Y. Mathers Foundation.

  11. SANS studies of interacting hemoglobin in intact erythrocytes

    SciTech Connect

    Krueger, S.; Nossal, R.

    1988-01-01

    Small angle neutron scattering (SANS) was used to investigate interaction forces between hemoglobin (Hb) molecules contained within human red cells. The scattering separately attributable to cell membranes and intracellular Hb was identified. A series of D/sub 2/O-H/sub 2/O contrast variation measurements were made in order to establish conditions for which scattering from the cell membrane is minimized (approximately 15% D/sub 2/O). Measurements then were performed to examine changes in intermolecular Hb interactions occurring when the cells are contracted or swollen by varying the ionic strength of the suspension buffer. The scattering cross-sections were fitted to structure factors computed by a mean spherical approximation, and molecular parameters thereby extracted. Oxygenation studies on normal cells were performed, and results contrasted with those of similar studies of erythrocytes obtained from sickle cell disease patients.

  12. A Journey in Science: Early Lessons from the Hemoglobin Field

    PubMed Central

    Weatherall, David J

    2014-01-01

    Real innovations in medicine and science are historic and singular; the stories behind each occurrence are precious. At Molecular Medicine we have established the Anthony Cerami Award in Translational Medicine to document and preserve these histories. The monographs recount the seminal events as told in the voice of the original investigators who provided the crucial early insight. These essays capture the essence of discovery, chronicling the birth of ideas that created new fields of research; and launched trajectories that persisted and ultimately influenced how disease is prevented, diagnosed, and treated. In this volume, the Cerami Award Monograph is by David J Weatherall, Founder, Weatherall Institute of Molecular Medicine, Oxford University, John Radcliffe Hospital. A visionary in the field of hemoglobin, this is the story of Professor Weatherall’s scientific journey. PMID:25548947

  13. Mitochondrial Respiration and Hemoglobin Gene Expression in Barley Aleurone Tissue.

    PubMed Central

    Nie, X.; Hill, R. D.

    1997-01-01

    Previous studies have shown that plant hemoglobin (Hb) mRNA is expressed in barley (Hordeum vulgare L.) aleurone layers during hypoxia. We have examined the effect of a number of respiratory inhibitors on barley aleurone layers to determine the factors that influence Hb gene expression. Respiratory inhibitors that reduce O2 consumption, such as CO, cyanide, and antimycin A, strongly enhanced Hb mRNA levels. Treatment with the oxidative phosphorylation uncoupler 2,4-dinitrophenol markedly increased O2 consumption and had a similar positive effect on Hb gene expression. Hb transcript levels were also stimulated by the ATP synthase inhibitor oligomycin. The results suggest that the expression of Hb is not directly influenced by O2 usage or availability but is influenced by the availability of ATP in the tissue. PMID:12223746

  14. A new polyethyleneglycol-derivatized hemoglobin derivative with decreased oxygen affinity and limited toxicity.

    PubMed

    Zolog, Oana; Mot, Augustin; Deac, Florina; Roman, Alina; Fischer-Fodor, Eva; Silaghi-Dumitrescu, Radu

    2011-01-01

    A new protocol is described for derivatization of hemoglobin with polyethyleneglycol (PEG) via reaction of the unmodified native hemoglobin with an activated amine-reacting polyethylene glycol derivative which, unlike protocols previously described, leads to formation of a peptide bond between hemoglobin and PEG. Dioxygen binding and peroxide reactivities of the derivatized hemoglobin are examined, and found to be within reasonable limits, with the particular observation that, unlike with a few other derivatization protocols, the dioxygen affinity is slightly lower than that of native Hb. In cell culture tests (human umbilical vein epithelial cells, HUVEC), the derivatization protocol induces no toxic effect. These results show promise towards applicability for production of hemoglobin-based blood substitutes. PMID:21161348

  15. A new polyethyleneglycol-derivatized hemoglobin derivative with decreased oxygen affinity and limited toxicity.

    PubMed

    Zolog, Oana; Mot, Augustin; Deac, Florina; Roman, Alina; Fischer-Fodor, Eva; Silaghi-Dumitrescu, Radu

    2011-01-01

    A new protocol is described for derivatization of hemoglobin with polyethyleneglycol (PEG) via reaction of the unmodified native hemoglobin with an activated amine-reacting polyethylene glycol derivative which, unlike protocols previously described, leads to formation of a peptide bond between hemoglobin and PEG. Dioxygen binding and peroxide reactivities of the derivatized hemoglobin are examined, and found to be within reasonable limits, with the particular observation that, unlike with a few other derivatization protocols, the dioxygen affinity is slightly lower than that of native Hb. In cell culture tests (human umbilical vein epithelial cells, HUVEC), the derivatization protocol induces no toxic effect. These results show promise towards applicability for production of hemoglobin-based blood substitutes.

  16. Identification of hemoglobin variants by top-down mass spectrometry using selected diagnostic product ions.

    PubMed

    Coelho Graça, Didia; Hartmer, Ralf; Jabs, Wolfgang; Beris, Photis; Clerici, Lorella; Stoermer, Carsten; Samii, Kaveh; Hochstrasser, Denis; Tsybin, Yury O; Scherl, Alexander; Lescuyer, Pierre

    2015-04-01

    Hemoglobin disorder diagnosis is a complex procedure combining several analytical steps. Due to the lack of specificity of the currently used protein analysis methods, the identification of uncommon hemoglobin variants (proteoforms) can become a hard task to accomplish. The aim of this work was to develop a mass spectrometry-based approach to quickly identify mutated protein sequences within globin chain variants. To reach this goal, a top-down electron transfer dissociation mass spectrometry method was developed for hemoglobin β chain analysis. A diagnostic product ion list was established with a color code strategy allowing to quickly and specifically localize a mutation in the hemoglobin β chain sequence. The method was applied to the analysis of rare hemoglobin β chain variants and an (A)γ-β fusion protein. The results showed that the developed data analysis process allows fast and reliable interpretation of top-down electron transfer dissociation mass spectra by nonexpert users in the clinical area.

  17. Oxidation of dibenzothiophene catalyzed by hemoglobin and other hemoproteins in various aqueous-organic media

    SciTech Connect

    Klyachko, N.L. Klibanov, A.M. )

    1992-10-01

    Biocatalytic oxidation of dibenzothiophene (a model of organic sulfur in coal) with hydrogen peroxide was investigated. It was found that various hemoproteins, both enzymic (e.g., horseradish peroxidase) and nonenzymic (e.g., bovine blood hemoglobin), readily oxidized dibensothiophene to its S-oxide and, to a minor extent, further to its S-dioxide (sulfone). This process catalyzed by hemoglobin was competent as an oxidation catalyst even in nearly dry organic solvents (with protic, acidic solvents being optimal), the highest conversions were observed in predominantly aqueous media. The hemoglobin-catalyzed oxidation of dibenzothiophene at low concentrations of the protein stopped long before all the substrate was oxidized. This phenomenon was caused by inactivation of hemoglobin by hydrogen peroxide that destroyed the heme moiety. The maximal degree of the hemoglobin-catalyzed dibenzothiophene oxidation was predicted, and found, to be strongly dependent on the reaction medium composition. 24 refs., 7 figs., 3 tabs.

  18. Radiation-induced changes in the optical properties of hemoglobin molecule

    NASA Astrophysics Data System (ADS)

    Selim, Nabila S.; El-Marakby, Seham M.

    2010-06-01

    Adult male Albino rats were exposed to different doses of gamma radiation from Cs-137 source. Hemoglobin samples were analyzed 24 h after irradiation. The UV-visible spectrum of hemoglobin molecule was measured in the range 200-700 nm. The overall spectrum of the hemoglobin molecule showed hypochromicity that increased with dose increase. To investigate the effect of radiation on the hemoglobin molecule, different parameters of the spectrum were calculated: molar absorption coefficient, absorption cross-section, transition dipole moment, dipole length, the optical energy gap and activation energy for each characteristic peak. The obtained results revealed that the radiation effect can induce rearrangement of the transition dipole moments and change molecular energy levels of the hemoglobin molecule.

  19. Facile heme vinyl posttranslational modification in a hemoglobin.

    PubMed

    Preimesberger, Matthew R; Wenke, Belinda B; Gilevicius, Lukas; Pond, Matthew P; Lecomte, Juliette T J

    2013-05-21

    Iron-protoporphyrin IX, or b heme, is utilized as such by a large number of proteins and enzymes. In some cases, notably the c-type cytochromes, this group undergoes a posttranslational covalent attachment to the polypeptide chain, which adjusts the physicochemical properties of the holoprotein. The hemoglobin from the cyanobacterium Synechocystis sp. PCC 6803 (GlbN), contrary to the archetypical hemoglobin, modifies its b heme covalently. The posttranslational modification links His117, a residue that does not coordinate the iron, to the porphyrin 2-vinyl substituent and forms a hybrid b/c heme. The reaction is an electrophilic addition that occurs spontaneously in the ferrous state of the protein. This apparently facile type of heme modification has been observed in only two cyanobacterial GlbNs. To explore the determinants of the reaction, we examined the behavior of Synechocystis GlbN variants containing a histidine at position 79, which is buried against the porphyrin 4-vinyl substituent. We found that L79H/H117A GlbN bound the heme weakly but nevertheless formed a cross-link between His79 Nε2 and the heme 4-Cα. In addition to this linkage, the single variant L79H GlbN also formed the native His117-2-Cα bond yielding an unprecedented bis-alkylated protein adduct. The ability to engineer the doubly modified protein indicates that the histidine-heme modification in GlbN is robust and could be engineered in different local environments. The rarity of the histidine linkage in natural proteins, despite the ease of reaction, is proposed to stem from multiple sources of negative selection. PMID:23607716

  20. Sickle hemoglobin gelation. Reaction order and critical nucleus size.

    PubMed Central

    Behe, M J; Englander, S W

    1978-01-01

    Sickle hemoglobin (Hb S) gelation displays kinetics consistent with a rate-limiting nucleation step. The approximate size of the critical nucleus can be inferred from the order of the reaction with respect to Hb S activity, but determination of the reaction order is complicated by the fact that Hb S activity is substantially different from Hb S concentration at the high protein concentrations required for gelation. Equilibrium and kinetic experiments on Hb S gelation were designed to evaluate the relative activity coefficient of Hb S as a function of concentration. These experiments used non-Hb S proteins to mimic, and thus evaluate, the effect on activity coefficients of increasing Hb S concentration. At Hb S concentrations near 20% the change in Hb S activity coefficient generates two-thirds of the apparent dependence of nucleation rate on Hb S concentration. When this effect is explicitly accounted for, the nucleation reaction is seen to be approximately 10th-order with respect to effective number concentration of Hb S. The closeness of the reaction order to the number of strands in models of Hb S fibers suggests a nucleus close to the size of one turn of the Hb S fiber. These experiments introduce a new approach to the study of Hb S gelation, the equal activity isotherm, used here also to show that Hb S.Hb A (normal adult hemoglobin) hybrids do incorporate into growing nuclei and stable microtubules but that A.S hybridization is neutral with respect to promotion of Hb S nucleation and the sol-gel equilibrium. PMID:667302

  1. Hemoglobin: a newly recognized binding protein for bacterial endotoxins (LPS).

    PubMed

    Roth, R I; Kaca, W; Levin, J

    1994-01-01

    Administration of purified hemoglobin (Hb) as a cell-free resuscitation fluid is associated with multiple organ toxicities. Many of these toxicities are characteristic of the pathophysiological effects of bacterial endotoxins (lipopolysaccharide, LPS). To better understand the potential role of LPS in the observed in vivo toxicities of Hb, we examined mixtures of Hb and LPS for evidence of LPS-Hb complex formation. LPS-Hb complexes were demonstrated by three techniques: ultrafiltration through 300 kDa cut-off membranes, which distinguished LPS in complexes (87-89% < 300 kDa) from LPS alone (90% > 300 kDa); density centrifugation through sucrose, which distinguished denser LPS alone from LPS-Hb complexes; and precipitation by 67% ethanol, which demonstrated 2-3 fold increased precipitability of Hb in complexes compared to Hb alone. Interaction of LPS with Hb was also associated with markedly increased biological activity of LPS, as manifested by enhancement of LPS activation of Limulus amebocyte lysate (LAL), increased release of human mononuclear cell tissue factor, and enhanced production of human endothelial cell tissue factor. These results demonstrated that hemoglobin can serve as an endotoxin binding protein, and that this interaction results in the alteration of several of the physical characteristics of LPS and enhancement of the biological activities of LPS. These findings suggest that a mechanism for the toxicity of infused Hb in vivo may involve potentiation of the biological effects of LPS. In addition, these observations suggest a mechanism by which LPS-related morbidity during sepsis could be enhanced by erythrocyte hemolysis.

  2. Treatment of periodontal disease in diabetics reduces glycated hemoglobin.

    PubMed

    Grossi, S G; Skrepcinski, F B; DeCaro, T; Robertson, D C; Ho, A W; Dunford, R G; Genco, R J

    1997-08-01

    Periodontal disease is a common infection-induced inflammatory disease among individuals suffering from diabetes mellitus. The purpose of this study was to assess the effects of treatment of periodontal disease on the level of metabolic control of diabetes. A total of 113 Native Americans (81 females and 32 males) suffering from periodontal disease and non-insulin dependent diabetes mellitus (NIDDM) were randomized into 5 treatment groups. Periodontal treatment included ultrasonic scaling and curettage combined with one of the following antimicrobial regimens: 1) topical water and systemic doxycycline, 100 mg for 2 weeks; 2) topical 0.12% chlorhexidine (CHX) and systemic doxycycline, 100 mg for 2 weeks; 3) topical povidone-iodine and systemic doxycycline, 100 mg for 2 weeks; 4) topical 0.12% CHX and placebo; and 5) topical water and placebo (control group). Assessments were performed prior to and at 3 and 6 months after treatment and included probing depth (PD), clinical attachment level (CAL), detection of Porphyromonas gingivalis in subgingival plaque and determination of serum glucose and glycated hemoglobin (HbA1c). After treatment all study groups showed clinical and microbial improvement. The doxycycline-treated groups showed the greatest reduction in probing depth and subgingival Porphyromonas gingivalis compared to the control group. In addition, all 3 groups receiving systemic doxycycline showed, at 3 months, significant reductions (P < or = 0.04) in mean HbA1c reaching nearly 10% from the pretreatment value. Effective treatment of periodontal infection and reduction of periodontal inflammation is associated with a reduction in level of glycated hemoglobin. Control of periodontal infections should thus be an important part of the overall management of diabetes mellitus patients.

  3. Impact of higher hemoglobin targets on blood pressure and clinical outcomes: a secondary analysis of CHOIR

    PubMed Central

    Inrig, Jula K.; Sapp, Shelly; Barnhart, Huiman; Patel, Uptal D.; Reddan, Donal; Singh, Ajay; Califf, Robert M.; Szczech, Lynda

    2012-01-01

    Background Targeting a higher hemoglobin in patients with chronic kidney disease leads to adverse cardiovascular outcomes, yet the reasons remain unclear. Herein, we sought to determine whether changes in erythropoiesis-stimulating agent (ESA) dose and in hemoglobin were predictive of changes in blood pressure (BP) and whether these changes were associated with cardiovascular outcomes. Methods In this secondary analysis of 1421 Correction of Hemoglobin and Outcomes in Renal Disease (CHOIR) participants, mixed model analyses were used to describe monthly changes in ESA dose and hemoglobin with changes in diastolic BP (DBP) and systolic BP (SBP). Poisson modeling was performed to determine whether changes in hemoglobin and BP were associated with the composite end point of death or cardiovascular outcomes. Results Monthly average DBP, but not SBP, was higher in participants in the higher hemoglobin arm. Increases in ESA doses and in hemoglobin were significantly associated with linear increases in DBP, but not consistently with increases in SBP. In models adjusted for demographics and comorbid conditions, increases in ESA dose (>0 U) and larger increases in hemoglobin (>1.0 g/dL/month) were associated with poorer outcomes [event rate ratio per 1000 U weekly dose per month increase 1.05, (1.02–1.08), P = 0.002 and event rate ratio 1.70 (1.02–2.85), P = 0.05, respectively]. However, increasing DBP was not associated with adverse outcomes [event rate ratio 1.01 (0.98–1.03), P = 0.7]. Conclusion Among CHOIR participants, higher hemoglobin targets, increases in ESA dose and in hemoglobin were associated both with increases in DBP and with higher event rates; however, increasing DBP was not associated with adverse outcomes. PMID:22573238

  4. Development of a method to produce hemoglobin in a bioreactor culture of Escherichia coli BL21(DE3) transformed with a plasmid containing Plesiomonas shigelloides heme transport genes and modified human hemoglobin genes.

    PubMed

    Smith, B J Z; Gutierrez, P; Guerrero, E; Brewer, C J; Henderson, D P

    2011-09-01

    We describe a method for production of recombinant human hemoglobin by Escherichia coli grown in a bioreactor. E. coli BL21(DE3) transformed with a plasmid containing hemoglobin genes and Plesiomonas shigelloides heme transport genes reached a cell dry weight of 83.64 g/liter and produced 11.92 g/liter of hemoglobin in clarified lysates.

  5. Hemoglobin system of Sparus aurata: changes in fishes farmed under extreme conditions.

    PubMed

    Campo, Salvatore; Nastasi, Giancarlo; D'Ascola, Angela; Campo, Giuseppe M; Avenoso, Angela; Traina, Paola; Calatroni, Alberto; Burrascano, Emanuele; Ferlazzo, Alida; Lupidi, Giulio; Gabbianelli, Rosita; Falcioni, Giancarlo

    2008-09-15

    In order to gain more knowledge on the stress responses of gilhead seabream (Sparus aurata) under extreme conditions, this study investigated the functional properties of the hemoglobin system and globin gene expression under hypoxia and low salinity. The oxygen affinity for the two hemoglobin components present inside the S. aurata erythrocyte was practically identical as was the influence of protons and organic phosphates (Root effect). The quantification of S. aurata hemoglobin fractions performed by HPLC and the data on gene expression of globin chains assayed by PCR indicate that under hypoxia and low salinity there is a change in the ratio between the two different hemoglobin components. The result indicating that the distinct hemoglobins present in S. aurata erythrocyte have almost identical functional properties, does not explain the adaptive response (expression change) following exposure of the animal to hypoxia or low salinity on the basis of their function as oxygen transporter. We hypothesize that other parallel biological functions that the hemoglobin molecule is known to display within the erythrocyte are involved in adaptive molecular mechanisms. The autoxidation-reduction cycle of hemoglobin could be involved in the response to particular living conditions.

  6. Effect of the N-terminal residues on the quaternary dynamics of human adult hemoglobin

    NASA Astrophysics Data System (ADS)

    Chang, Shanyan; Mizuno, Misao; Ishikawa, Haruto; Mizutani, Yasuhisa

    2016-05-01

    The protein dynamics of human hemoglobin following ligand photolysis was studied by time-resolved resonance Raman spectroscopy. The time-resolved spectra of two kinds of recombinant hemoglobin expressed in Escherichia coli, normal recombinant hemoglobin and the α(V1M)/β(V1M) double mutant, were compared with those of human adult hemoglobin (HbA) purified from blood. A frequency shift of the iron-histidine stretching [ν(Fe-His)] band was observed in the time-resolved spectra of all three hemoglobin samples, indicative of tertiary and quaternary changes in the protein following photolysis. The spectral changes of the α(V1M)/β(V1M) double mutant were distinct from those of HbA in the tens of microseconds region, whereas the spectral changes of normal recombinant hemoglobin were similar to those of HbA isolated from blood. These results demonstrated that a structural change in the N-termini is involved in the second step of the quaternary structure change of hemoglobin. We discuss the implications of these results for understanding the allosteric pathway of HbA.

  7. Engineering the oxygen sensing regulation results in an enhanced recombinant human hemoglobin production by Saccharomyces cerevisiae.

    PubMed

    Martínez, José L; Liu, Lifang; Petranovic, Dina; Nielsen, Jens

    2015-01-01

    Efficient production of appropriate oxygen carriers for transfusions (blood substitutes or artificial blood) has been pursued for many decades, and to date several strategies have been used, from synthetic polymers to cell-free hemoglobin carriers. The recent advances in the field of metabolic engineering also allowed the generation of different genetically modified organisms for the production of recombinant human hemoglobin. Several studies have showed very promising results using the bacterium Escherichia coli as a production platform, reporting hemoglobin titers above 5% of the total cell protein content. However, there are still certain limitations regarding the protein stability and functionality of the recombinant hemoglobin produced in bacterial systems. In order to overcome these limitations, yeast systems have been proposed as the eukaryal alternative. We recently reported the generation of a set of plasmids to produce functional human hemoglobin in Saccharomyces cerevisiae, with final titers of active hemoglobin exceeding 4% of the total cell protein. In this study, we propose a strategy for further engineering S. cerevisiae by altering the oxygen sensing pathway by deleting the transcription factor HAP1, which resulted in an increase of the final recombinant active hemoglobin titer exceeding 7% of the total cellular protein.

  8. Trypanosomatid parasites rescue heme from endocytosed hemoglobin through lysosomal HRG transporters.

    PubMed

    Cabello-Donayre, María; Malagarie-Cazenave, Sophie; Campos-Salinas, Jenny; Gálvez, Francisco J; Rodríguez-Martínez, Alba; Pineda-Molina, Estela; Orrego, Lina M; Martínez-García, Marta; Sánchez-Cañete, María P; Estévez, Antonio M; Pérez-Victoria, José M

    2016-09-01

    Pathogenic trypanosomatid parasites are auxotrophic for heme and they must scavenge it from their human host. Trypanosoma brucei (responsible for sleeping sickness) and Leishmania (leishmaniasis) can fulfill heme requirement by receptor-mediated endocytosis of host hemoglobin. However, the mechanism used to transfer hemoglobin-derived heme from the lysosome to the cytosol remains unknown. Here we provide strong evidence that HRG transporters mediate this essential step. In bloodstream T. brucei, TbHRG localizes to the endolysosomal compartment where endocytosed hemoglobin is known to be trafficked. TbHRG overexpression increases cytosolic heme levels whereas its downregulation is lethal for the parasites unless they express the Leishmania orthologue LmHR1. LmHR1, known to be an essential plasma membrane protein responsible for the uptake of free heme in Leishmania, is also present in its acidic compartments which colocalize with endocytosed hemoglobin. Moreover, LmHR1 levels modulated by its overexpression or the abrogation of an LmHR1 allele correlate with the mitochondrial bioavailability of heme from lysosomal hemoglobin. In addition, using heme auxotrophic yeasts we show that TbHRG and LmHR1 transport hemoglobin-derived heme from the digestive vacuole to the cytosol. Collectively, these results show that trypanosomatid parasites rescue heme from endocytosed hemoglobin through endolysosomal HRG transporters, which could constitute novel drug targets. PMID:27328668

  9. [Analytical problems in determination of hemoglobin A1c and the different ways of its interpretation].

    PubMed

    Góth, László

    2009-04-19

    Glycated proteins are formed during the nonenzymatic reaction of glucose and amino groups of proteins. Hemoglobin A1c is formed by the condensation of glucose with the N-terminal valine residue of each beta-chain of hemoglobin A. The amount of glycated hemoglobin in blood depends on both life-span of red blood cells and blood glucose concentration. As the rate of formation of hemoglobin A1c is directly proportional to the concentration of glucose in the blood, it represent the integrated values for glucose over the preceding 6 to 8 weeks. Hemoglobin A1c determination is widely used for monitoring long-term glycemic control, and it is a risk factor for complications of diabetes. The concentration of blood hemoglobin A1c depends on further factors such as half-life of hemoglobin, blood carbohydrates, blood analytes, methods of determination and calibration. Committees were established under the auspices of the American Association of Clinical Chemistry, American Diabetes Association, International Federation of Clinical Chemistry (IFCC) to standardize HbA1c assays (DCCT: Diabetes Control and Complications Trial, NGSP: National Glycohemoglobin Standardization Program, IFCC reference method for measurement of HbA1c). The NGSP recommends to report HbA1c result in % (g HbA1c/g hemoglobin) while IFCC suggests mmol HbA1c/mol hemoglobin A. Reports are presenting mathematical relationship between HbA1c and average glucose concentration in blood, however, the clinical usefulness of estimating average serum glucose from HbA1c level is under discussion. PMID:19362928

  10. Maternal HIV status affects the infant hemoglobin level

    PubMed Central

    Feleke, Berhanu Elfu

    2016-01-01

    Abstract Children, especially infants, are highly vulnerable to iron-deficiency anemia because of their rapid growth of the brain and the rest of the body. The objectives of this study were to compare the prevalence of iron-deficiency anemia in infants born from HIV-positive mothers and HIV-negative mothers and to identify the determinants of iron-deficiency anemia in infants. A comparative cross-sectional study was conducted in Bahir Dar city. Simple random sampling technique was used to select the study participants. Mothers were interviewed; blood samples were collected from mothers and infants to measure the hemoglobin level and anthropometric indicators were obtained from the infants using world health organization standards. Descriptive statistics were used to estimate the prevalence of infantile anemia. Binary logistic regression and multiple linear regressions were used to identify the determinants of infant anemia. A total of 1459 infants born from HIV-positive and HIV-negative mothers were included. The prevalence of iron-deficiency anemia in infants born from HIV-positive and HIV-negative mothers was 41.9% (95% CI: 39–44). Infantile iron-deficiency anemia was associated with maternal HIV infection (adjusted odds ratio [AOR] 2.54 [95% CI: 1.65–3.9]), stunting (AOR 3.46 [95% CI: 2.41–4.97]), low income (AOR 2.72 [95% CI: 2–3.73]), maternal malaria during pregnancy (AOR 1.81 [95% CI: 1.33–2.47]), use of cow milk before 6 month (AOR 1.82 [95% CI: 1.35–2.45]), residence (AOR 0.09 [95% CI: 0.06–0.13]), history of cough or fever 7 days preceding the survey (AOR 2.71 [95% CI: 1.99–3.69]), maternal hemoglobin (B 0.65 [95% CI: 0.61–0.68]), educational status of mother (B 0.22 [95% CI: 0.2–0.23]), age of the mother (B –0.03 [95% CI: –0.03, –0.02]), and family size (B –0.14 [95% CI: –0.18,–0.11]). PMID:27495044

  11. Heme degradation upon production of endogenous hydrogen peroxide via interaction of hemoglobin with sodium dodecyl sulfate.

    PubMed

    Salehi, N; Moosavi-Movahedi, A A; Fotouhi, L; Yousefinejad, S; Shourian, M; Hosseinzadeh, R; Sheibani, N; Habibi-Rezaei, M

    2014-04-01

    In this study the hemoglobin heme degradation upon interaction with sodium dodecyl sulfate (SDS) was investigated using UV-vis and fluorescence spectroscopy, multivariate curve resolution analysis, and chemiluminescence method. Our results showed that heme degradation occurred during interaction of hemoglobin with SDS producing three fluorescent components. We showed that the hydrogen peroxide, produced during this interaction, caused heme degradation. In addition, the endogenous hydrogen peroxide was more effective in hemoglobin heme degradation compared to exogenously added hydrogen peroxide. The endogenous form of hydrogen peroxide altered oxyHb to aquamethemoglobin and hemichrome at low concentration. In contrast, the exogenous hydrogen peroxide lacked this ability under same conditions.

  12. Long Range Correlation of Hydrophilicity and Flexibility Along the Hemoglobin Chain

    SciTech Connect

    Craciun, D.; Isvoran, A.; Avram, N. M.

    2010-08-04

    Within this study, we reveal the long range correlation concerning hydrophilicity and flexibility along sequences of hemoglobins belonging to different organisms and we compare them with the long range correlations properties obtained for other protein families. For all hemoglobins considered, we investigate two discrete spatial series: the hydrophilicity and flexibility respectively. We apply the nonlinear analysis methods to analyze the two spatial series by calculating the spectral coefficient {beta}, the scaling exponent {alpha} and Hurst exponent H. The obtained values for the mentioned coefficients suggest long range correlation within the analyzed sequences of hemoglobins in good agreement with those obtained for the calcium binding proteins and hydrolases.

  13. Comparison of Hemoglobin Levels Before and After Hemodialysis and Their Effects on Erythropoietin Dosing and Cost

    PubMed Central

    Sagheb, Mohammad Mahdi; Fallahzadeh, Mohammad Amin; Moaref, Alireza; Fallahzadeh, Mohammad Hossein; Dormanesh, Banafshe

    2016-01-01

    Background Hemoglobin levels measured after hemodialysis, as compared to hemoglobin levels measured before hemodialysis, are suggested to be a more accurate reflection of the hemoglobin levels between hemodialysis sessions, and to be a better reference point for adjusting erythropoietin dosing. Objectives The aim of this study was to compare the hemoglobin levels before and after hemodialysis, to calculate the required erythropoietin doses based on these levels, and to develop a model to predict effective erythropoietin dosing. Patients and Methods In this cross-sectional study, the hemoglobin levels of 52 patients with end-stage renal disease were measured before and after hemodialysis. The required erythropoietin doses and the differences in cost were calculated based on the hemoglobin levels before and after hemodialysis. A model to predict the adjusted erythropoietin dosages based on post-hemodialysis hemoglobin levels was proposed. Results Hemoglobin levels measured after hemodialysis were significantly higher than the hemoglobin levels before hemodialysis (11.1 ± 1.1 vs. 11.9 ± 1.2 g/dL, P < 0.001, 7% increase). The mean required erythropoietin dose based on post-hemodialysis hemoglobin levels was significantly lower than the corresponding erythropoietin dose based on pre-hemodialysis hemoglobin levels (10947 ± 6820 vs. 12047 ± 7542 U/week, P < 0.001, 9% decrease). The cost of erythropoietin was also significantly lower when post-hemodialysis levels were used (15.96 ± 9.85 vs. 17.57 ± 11.00 dollars/patient/week, P < 0.001). This translated into 83.72 dollars/patient/year in cost reduction. The developed model for predicting the required dosage is: Erythropoietin (U/week) = 43540.8 + (-2734.8) × Post-hemodialysis Hb* (g/dL). [(R2) = 0.221; *P < 0.001]. Conclusions Using post-hemodialysis hemoglobin levels as a reference point for erythropoietin dosing can result in significant dose and cost reduction, and can protect hemodialysis patients from

  14. A Theoretical Study of some Rheological Properties of the Aggregation of the Molecules Deoxy- Hemoglobin S

    NASA Astrophysics Data System (ADS)

    Mensah, Francis; Grant, Julius; Thorpe, Arthur

    2010-02-01

    Sickle cell disease is a serious public health problem that affects many people worldwide. In this paper, the Langevin equation is used for hemoglobin's aggregation in sickle cell anemia. Several parameters are explored such as the time-dependent deformation of the aggregates whose plot gives a sigmoid, the time-dependent expressions obtained for the coefficient of viscosity and the elastic modulus which characterize the aggregation of the sickle hemoglobin. Other properties such as the viscoelastic and the elasto-thixotropic properties of the sickle hemoglobin polymer are also described. An attempt is made to approach the polymerization process in terms of a dynamical system. )

  15. Direct electrochemistry of hemoglobin in egg-phosphatidylcholine films and its catalysis to H(2)O(2).

    PubMed

    Han, Xiaojun; Huang, Weimin; Jia, Jianbo; Dong, Shaojun; Wang, Erkang

    2002-09-01

    Direct electrochemistry of hemoglobin was observed in stable thin film composed of a natural lipid (egg-phosphatidylcholine) and hemoglobin on pyrolytic graphite (PG) electrode. Hemoglobin in lipid films shows thin layer electrochemistry behavior. The formal potential E degrees ' of hemoglobin in the lipid film was linearly varied with pH in the range from 3.5 to 7.0 with a slope of -46.4 mV pH(-1). Hemoglobin in the lipid film exhibited elegant catalytic activity for electrochemical reduction of H(2)O(2), based which a unmediated biosensor for H(2)O(2) was developed.

  16. Human bulbar conjunctival hemodynamics in hemoglobin SS and SC disease.

    PubMed

    Wanek, Justin; Gaynes, Bruce; Lim, Jennifer I; Molokie, Robert; Shahidi, Mahnaz

    2013-08-01

    The known biophysical variations of hemoglobin (Hb) S and Hb C may result in hemodynamic differences between subjects with SS and SC disease. The purpose of this study was to measure and compare conjunctival hemodynamics between subjects with Hb SS and SC hemoglobinopathies. Image sequences of the conjunctival microcirculation were acquired in 9 healthy control subjects (Hb AA), 24 subjects with SC disease, and 18 subjects with SS disease, using a prototype imaging system. Diameter (D) and blood velocity (V) measurements were obtained in multiple venules of each subject. Data were categorized according to venule caliber by averaging V and D for venules with diameters less than (vessel size 1) or greater than (vessel size 2) 15 µm. V in vessel size 2 was significantly greater than V in vessel size 1 in the AA and SS groups (P ≥ 0.009), but not in the SC group (P = 0.1). V was significantly lower in the SC group as compared to the SS group (P = 0.03). In AA and SS groups, V correlated with D (P ≤ 0.005), but the correlation was not statistically significant in the SC group (P = 0.08). V was inversely correlated with hematocrit in the SS group for large vessels (P = 0.03); however, no significant correlation was found in the SC group (P ≥ 0.2). Quantitative assessment of conjunctival microvascular hemodynamics in SS and SC disease may advance understanding of sickle cell disease pathophysiology and thereby improve therapeutic interventions.

  17. Hemoglobin Bohr effects: atomic origin of the histidine residue contributions.

    PubMed

    Zheng, Guishan; Schaefer, Michael; Karplus, Martin

    2013-11-26

    The Bohr effect in hemoglobin, which refers to the dependence of the oxygen affinity on the pH, plays an important role in its cooperativity and physiological function. The dominant contribution to the Bohr effect arises from the difference in the pKa values of His residues of the unliganded (deoxy) and liganded (carbonmonoxy) structures. Using recent high resolution structures, the residue pKa values corresponding to the two structures are calculated. The method is based on determining the electrostatic interactions between residues in the protein, relative to those of the residue in solution, by use of the linearized finite difference Poisson-Boltzmann equation and Monte Carlo sampling of protonation states. Given that good agreement is obtained with the available experimental values for the contribution of His residues in HbA to the Bohr effect, the calculated results are used to determine the atomic origin of the pKa shift between deoxy and carbonmonoxy HbA. The contributions to the pKa shift calculated by means of the linear response approximation show that the salt bridge involving His146 plays an important role in the alkaline Bohr effect, as suggested by Perutz but that other interactions are significant as well. A corresponding analysis is made for the contribution of His143 to the acid Bohr effect for which there is no proposed explanation. The method used is summarized and the program by which it is implemented is described in the Appendix .

  18. Nitrite attenuated hypochlorous acid-mediated heme degradation in hemoglobin.

    PubMed

    Lu, Naihao; Li, Jiayu; Ren, Xiaoming; Tian, Rong; Peng, Yi-Yuan

    2015-08-01

    Hypochlorous acid (HOCl) is elevated in many inflammatory diseases and causes the accumulation of free iron. Through the Fenton reaction, free iron has the ability to generate free radicals and subsequently is toxic. Recent studies have demonstrated that HOCl participates in heme destruction of hemoglobin (Hb) and free iron release. In this study, it was showed that nitrite (NO2(-)) could prevent HOCl-mediated Hb heme destruction and free iron release. Also, NO2(-) prevented HOCl-mediated loss of Hb peroxidase activity. After the NO2(-)/HOCl treatment, Tyr 42 in α-chain was found to be nitrated in Hb, attenuating the electron transferring abilities of phenolic compounds. The protective effects of NO2(-) on HOCl-induced heme destruction were attributed to its reduction of ferryl Hb and/or direct scavenging of HOCl. Therefore, NO2(-) could show protective effects in some inflammatory diseases by preventing HOCl-mediated heme destruction of hemoproteins and free iron release. PMID:26051522

  19. Effects of rutin on the redox reactions of hemoglobin.

    PubMed

    Lu, Naihao; Ding, Yun; Yang, Zhen; Gao, Pingzhang

    2016-08-01

    Flavonoids are widely used to attenuate oxidative damage in vitro and in vivo. In this study, we investigated the influence of rutin (quercetin-3-rhamnosylglucoside) on hemoglobin (Hb)- dependent redox reactions, i.e. oxidative stability of Hb and its cytotoxic ferryl intermediate. It was found that rutin induced generation of H2O2, which in turn oxidized Hb rapidly. Meanwhile, rutin exhibited anti-oxidant effect by effectively reducing ferryl intermediate back to ferric Hb at physiological pH. In comparison with quercetin, rutin had stronger capability on reducing ferryl species while lesser pro-oxidant effect on H2O2 generation, thus it exhibited more protective effect on H2O2-induced Hb oxidation. Circular dichroism spectrum showed no significant change in the secondary structure of Hb after flavonoid addition, while molecular docking revealed different binding modes of quercetin and rutin with Hb. These results might provide new insights into the potential nutritional and physiological implications of rutin and quercetin with redox active heme proteins regarding their ani- and pro-oxidant effects.

  20. Resuscitation with increasing doses of diaspirin crosslinked hemoglobin in swine.

    PubMed

    Marchand, G; Dunlap, E; Farrell, L; Nigro, C; Burhop, K

    1996-09-01

    This study examined the effects of administering 0.5, 4, 10, and 30 mL/kg of Diaspirin Crosslinked Hemoglobin (DCLHb) in a swine model of non-lethal hemorrhagic shock. Thirty unanesthetized animals were bled (30 mL/kg, 1 mL/kg/min) and either recovered without treatment (Untreated Control, UC) or infused with 10 g/dL DCLHb (0.5, 4.0, 10 or 30 mL/kg at 1 mL/kg/min) or Lactated Ringer (LR, 90 mL/kg at 3 mL/kg/min). DCLHb caused dose-related increases in MAP. Both the 10 and 30 mL/kg doses of DCLHb increased MAP more than UC or LR. Lower doses of DCLHb and LR had effects on MAP similar to UC. After hemorrhage, CO increased in all groups. The effect of DCLHb on CO was dose-related. Only LR and 30 mL/kg of DCLHb transiently (through 90 min) increased CO more than UC. CO in animals given lower doses of DCLHb was comparable to UC. DCLHb (10 and 30 mL/kg) improved base excess and lactate concentrations, two indices of global perfusion, more rapidly and to a greater extent than either UC or LR. In this swine model of hemorrhage, even small doses of DCLHb exerted measurable beneficial effects on blood pressure and perfusion.

  1. Erythrocyte differentiation during the metamorphic hemoglobin switch of Rana catesbeiana.

    PubMed Central

    Dorn, A R; Broyles, R H

    1982-01-01

    Anurans (frogs and toads) switch from tadpole to adult hemoglobin synthesis during metamorphosis. A number of workers have attempted to determine whether tadpole and adult Hb types are expressed in the same or different erythroid cells during the switch. If the different Hb types are found in different cells during the transition, the switch in globin gene expression occurs at an early stage of cellular differentiation. Previous studies, in which immunocytochemical techniques were used to approach this question, are in conflict in regard to the metamorphic Hb switch of the North American bullfrog Rana catesbeiana. We have purified newly differentiating erythroid cells from the blood of metamorphosing tadpoles by using Percoll gradients. These new cells have an immature morphology, are very active in the synthesis of adult Hb, and contain no detectable tadpole Hb. The tadpole cells have no detectable adult Hb, are synthetically inactive, increase in density during the switch, and are then cleared from the circulation. Thus, only adult Hb expression is detected in newly differentiating erythroid cells during metamorphosis. Images PMID:6182567

  2. Quantification of hemoglobin variants by capillary isoelectric focusing.

    PubMed

    Hempe, J M; Craver, R D

    1994-12-01

    Capillary isoelectric focusing (cIEF) was used to identify and quantify major and minor hemoglobin (Hb) variants. Whole blood (approximately 10 microL required) hemolysate was analyzed with a commercial instrument equipped with a 50 microns (i.d.) x 27 cm coated capillary filled with 20 g/L ampholytes (pH 6-8) in 4 g/L methylcellulose (MC). Cathode and anode solutions were 20 mol/L NaOH and 100 mol/L H3PO4 in MC, respectively. Samples (approximately 40 nL) were applied via autosampler by low-pressure injection, focused for 3 min at 30 kV, and mobilized by simultaneous voltage and low pressure past the detector, where absorbance at 415 nm was analyzed by an automated data acquisition system. Blood from subjects with sickle cell trait, Hb S/C disease, and various beta-thalassemias were analyzed by cIEF in < 15 min. cIEF was used to separate Hb S from Hb D-Los Angeles. Assay precision determined with commercial controls gave CV < 2% for Hb A and S, and 1-11% for minor Hb variants A2, F, and A1c. Results obtained by cIEF for patients' samples agreed well with values determined by conventional assays (r2 > 0.95). The results demonstrate that cIEF is a rapid, sensitive, high-resolution automated method for routine quantitative clinical analysis of Hb variants.

  3. The interaction between hemoglobin and two surfactants with different charges.

    PubMed

    Liu, Wenjie; Guo, Xia; Guo, Rong

    2007-12-01

    The interactions of hemoglobin (Hb) with sodium dodecyl sulfate (SDS) and dodecyl trimethylammonium bromide (DTAB) are investigated by several methods. We observed the formation of hemichrome below the critical micelle concentration (cmc) of surfactant and the release of heme from Hb above the cmc. When pH value of Hb/surfactant system is lower than isoelectric point (pI) of Hb, the interaction of SDS with Hb is both electrostatic and hydrophobic, while the interaction of DTAB with Hb is hydrophobic mainly. On the contrary, when pH>pI, the interaction of SDS with Hb is hydrophobic mainly, while the interaction of DTAB with Hb is both electrostatic and hydrophobic. In the case where both the electrostatic interaction and hydrophobic interaction exist, the electrostatic interaction plays a more important role. Thus, SDS tends to interact with Hb more obviously than DTAB does when pHpI.

  4. Five Rare β Globin Chain Hemoglobin Variants in India.

    PubMed

    Colah, Roshan B; Nadkarni, Anita; Gorakshakar, Ajit; Sawant, Pratibha; Gorivale, Manju; Mehta, Pallavi; Sawant, Madhavi; Ghosh, Kanjaksha

    2016-06-01

    Thalassemias as well as structural hemoglobin (Hb) variants are common monogenic inherited disorders of Hb in India. In this paper we describe 5 rare β-chain Hb variants identified in the Indian population on the basis of high performance liquid chromatography (HPLC). Of these 3 were identified during antenatal screening of β-thalassemia while the other 2 cases were referred to us for a diagnostic work up. These 5 Hb variants were Hb British Columbia (β CD 101 GAG → AAG), Hb Saint Louis (β CD28 CTG → CAG), Hb G Coushatta (β CD 22 GAA → GCA), Hb Pyrgos (β CD 83 GGC → GAC) and Hb Agenogi (β CD 90 GAG → AAG). Hb Saint Louis and Hb G Coushatta eluted in the HbA2 window, Hb British Columbia and Hb Agenogi eluted in the Hb C window while Hb Pyrgos eluted in an unknown window on HPLC. They were all identified by DNA sequencing. The child having Hb St. Louis had hepatosplenomegaly and anemia while the individuals with the other 4 variants were asymptomatic. Rare Hb variants are diagnostic curiosities that may be encountered by laboratories. Correct identification requires the application of more than one technique to avoid misdiagnosing them as more common variants (e.g. St. Louis and G Coushatta as E or D Iran on HPLC. Some, like G Coushatta may interfere with HPLC-based HbA1c estimation). PMID:27408413

  5. Variant subunit specificity in the quaternary structure of Artemia hemoglobin.

    PubMed

    Vandenberg, Cassandra J; Matthews, Charles M; Trotman, Clive N A

    2002-08-01

    The brine shrimp Artemia has three extracellular hemoglobins (Hbs) that are developmentally expressed and exhibit distinct oxygen-binding characteristics (Heip, Moens, and Kondo 1978; Heip et al. 1978 ). These Hbs are composed of two polymers, each of which comprises nine covalently linked globin domains. Although the cDNA sequences of two nine-domain globins from Artemia have been published, there is evidence for the existence of further expressed globin genes (Manning, Trotman, and Tate 1990 ). In the present study extensive analysis at the cDNA and genomic levels was performed in order to determine the globin gene copy number in Artemia. Sequence and Southern analysis suggest that four Hb polymers (T1, T2, C1, and C2) are expressed in Artemia. In addition, there is also at least one globin pseudogene. Protein sequencing of the native Hbs revealed that there are limitations on which two polymers can associate. The composition of the Hbs has been determined to be: Hb I, C1C2; Hb II, C1T2; and Hb III, T1T2. These pairings allow the levels of the three Artemia Hbs to be regulated independently by polymer expression alone, therefore explaining the previously inconsistent developmental and hypoxia-induced expression patterns. PMID:12140240

  6. Differential sensitivity of Chironomus and human hemoglobin to gamma radiation.

    PubMed

    Gaikwad, Pallavi S; Panicker, Lata; Mohole, Madhura; Sawant, Sangeeta; Mukhopadhyaya, Rita; Nath, Bimalendu B

    2016-08-01

    Chironomus ramosus is known to tolerate high doses of gamma radiation exposure. Larvae of this insect possess more than 95% of hemoglobin (Hb) in its circulatory hemolymph. This is a comparative study to see effect of gamma radiation on Hb of Chironomus and humans, two evolutionarily diverse organisms one having extracellular and the other intracellular Hb respectively. Stability and integrity of Chironomus and human Hb to gamma radiation was compared using biophysical techniques like Dynamic Light Scattering (DLS), UV-visible spectroscopy, fluorescence spectrometry and CD spectroscopy after exposure of whole larvae, larval hemolymph, human peripheral blood, purified Chironomus and human Hb. Sequence- and structure-based bioinformatics methods were used to analyze the sequence and structural similarities or differences in the heme pockets of respective Hbs. Resistivity of Chironomus Hb to gamma radiation is remarkably higher than human Hb. Human Hb exhibited loss of heme iron at a relatively low dose of gamma radiation exposure as compared to Chironomus Hb. Unlike human Hb, the heme pocket of Chironomus Hb is rich in aromatic amino acids. Higher hydophobicity around heme pocket confers stability of Chironomus Hb compared to human Hb. Previously reported gamma radiation tolerance of Chironomus can be largely attributed to its evolutionarily ancient form of extracellular Hb as evident from the present study.

  7. Erythrocyte differentiation during the metamorphic hemoglobin switch of Rana catesbeiana.

    PubMed

    Dorn, A R; Broyles, R H

    1982-09-01

    Anurans (frogs and toads) switch from tadpole to adult hemoglobin synthesis during metamorphosis. A number of workers have attempted to determine whether tadpole and adult Hb types are expressed in the same or different erythroid cells during the switch. If the different Hb types are found in different cells during the transition, the switch in globin gene expression occurs at an early stage of cellular differentiation. Previous studies, in which immunocytochemical techniques were used to approach this question, are in conflict in regard to the metamorphic Hb switch of the North American bullfrog Rana catesbeiana. We have purified newly differentiating erythroid cells from the blood of metamorphosing tadpoles by using Percoll gradients. These new cells have an immature morphology, are very active in the synthesis of adult Hb, and contain no detectable tadpole Hb. The tadpole cells have no detectable adult Hb, are synthetically inactive, increase in density during the switch, and are then cleared from the circulation. Thus, only adult Hb expression is detected in newly differentiating erythroid cells during metamorphosis.

  8. [On the modified process of human hemoglobin based blood substitutes].

    PubMed

    Li, Fengjuan; Zhang, Honghui; Wang, Jinfeng; Yang, Chengmin

    2009-10-01

    Purified hemoglobin was modified with pyridoxal 5-phosphate(PLP) and polymerized with glutaric dialdehyde(GDA) to get the products. By comparison of the physical, chemical and biological properties of different procedures for modification before and after polymerization, there is no significant difference in molecular distribution, methemoglobin(MetHb) concentration, oxygen carrier capacity, P50 and spectra. Furthermore, the procedure of modification after polymerization can save PLP greatly and decrease cost greatly. So the procedure of modification after polymerization is a better way in research and production. The addition of GDA could control the increasing of MetHb. By comparison on the physical, chemical and biological properties of different procedures, there is no significant difference in molecular distribution, MetHb concentration, oxygen carrier capacity and spectra between the procedure of adding GDA before PLP and that after PLP. But the P50 of adding GDA before PLP is much lower than that after PLP. So the procedure of adding GDA after PLP is a better way.

  9. Extracellular hemoglobin: the case of a friend turned foe

    PubMed Central

    Quaye, Isaac K.

    2015-01-01

    Hemoglobin (Hb) is a highly conserved molecule present in all life forms and functionally tied to the complexity of aerobic organisms on earth in utilizing oxygen from the atmosphere and delivering to cells and tissues. This primary function sustains the energy requirements of cells and maintains cellular homeostasis. Decades of intensive research has presented a paradigm shift that shows how the molecule also functions to facilitate smooth oxygen delivery through the cardiovascular system for cellular bioenergetic homeostasis and signaling for cell function and defense. These roles are particularly highlighted in the binding of Hb to gaseous molecules carbon dioxide (CO2), nitric oxide (NO) and carbon monoxide (CO), while also serving indirectly or directly as sources of these signaling molecules. The functional activities impacted by Hb outside of bioenergetics homeostasis, include fertilization, signaling functions, modulation of inflammatory responses for defense and cell viability. These activities are efficiently executed while Hb is sequestered safely within the confines of the red blood cell (rbc). Outside of rbc confines, Hb disaggregates and becomes a danger molecule to cell survival. In these perpectives, Hb function is broadly dichotomous, either a friend in its natural environment providing and facilitating the means for cell function or foe when dislocated from its habitat under stress or pathological condition disrupting cell function. The review presents insights into how this dichotomy in function manifests. PMID:25941490

  10. Intermolecular interactions, nucleation, and thermodynamics of crystallization of hemoglobin C.

    PubMed Central

    Vekilov, Peter G; Feeling-Taylor, Angela R; Petsev, Dimiter N; Galkin, Oleg; Nagel, Ronald L; Hirsch, Rhoda Elison

    2002-01-01

    The mutated hemoglobin HbC (beta 6 Glu-->Lys), in the oxygenated (R) liganded state, forms crystals inside red blood cells of patients with CC and SC diseases. Static and dynamic light scattering characterization of the interactions between the R-state (CO) HbC, HbA, and HbS molecules in low-ionic-strength solutions showed that electrostatics is unimportant and that the interactions are dominated by the specific binding of solutions' ions to the proteins. Microscopic observations and determinations of the nucleation statistics showed that the crystals of HbC nucleate and grow by the attachment of native molecules from the solution and that concurrent amorphous phases, spherulites, and microfibers are not building blocks for the crystal. Using a novel miniaturized light-scintillation technique, we quantified a strong retrograde solubility dependence on temperature. Thermodynamic analyses of HbC crystallization yielded a high positive enthalpy of 155 kJ mol(-1), i.e., the specific interactions favor HbC molecules in the solute state. Then, HbC crystallization is only possible because of the huge entropy gain of 610 J mol(-1) K(-1), likely stemming from the release of up to 10 water molecules per protein intermolecular contact-hydrophobic interaction. Thus, the higher crystallization propensity of R-state HbC is attributable to increased hydrophobicity resulting from the conformational changes that accompany the HbC beta 6 mutation. PMID:12124294

  11. Differential sensitivity of Chironomus and human hemoglobin to gamma radiation.

    PubMed

    Gaikwad, Pallavi S; Panicker, Lata; Mohole, Madhura; Sawant, Sangeeta; Mukhopadhyaya, Rita; Nath, Bimalendu B

    2016-08-01

    Chironomus ramosus is known to tolerate high doses of gamma radiation exposure. Larvae of this insect possess more than 95% of hemoglobin (Hb) in its circulatory hemolymph. This is a comparative study to see effect of gamma radiation on Hb of Chironomus and humans, two evolutionarily diverse organisms one having extracellular and the other intracellular Hb respectively. Stability and integrity of Chironomus and human Hb to gamma radiation was compared using biophysical techniques like Dynamic Light Scattering (DLS), UV-visible spectroscopy, fluorescence spectrometry and CD spectroscopy after exposure of whole larvae, larval hemolymph, human peripheral blood, purified Chironomus and human Hb. Sequence- and structure-based bioinformatics methods were used to analyze the sequence and structural similarities or differences in the heme pockets of respective Hbs. Resistivity of Chironomus Hb to gamma radiation is remarkably higher than human Hb. Human Hb exhibited loss of heme iron at a relatively low dose of gamma radiation exposure as compared to Chironomus Hb. Unlike human Hb, the heme pocket of Chironomus Hb is rich in aromatic amino acids. Higher hydophobicity around heme pocket confers stability of Chironomus Hb compared to human Hb. Previously reported gamma radiation tolerance of Chironomus can be largely attributed to its evolutionarily ancient form of extracellular Hb as evident from the present study. PMID:27237970

  12. Low hemoglobin levels are associated with upper gastrointestinal bleeding

    PubMed Central

    Tomizawa, Minoru; Shinozaki, Fuminobu; Hasegawa, Rumiko; Shirai, Yoshinori; Motoyoshi, Yasufumi; Sugiyama, Takao; Yamamoto, Shigenori; Ishige, Naoki

    2016-01-01

    Upper gastrointestinal (GI) bleeding can be fatal. Blood test variables were reviewed in search of threshold values to detect the presence of occult upper GI bleeding. The records of 1,023 patients who underwent endoscopy at the National Hospital Organization Shimoshizu Hospital from October 2014, to September 2015, were retrospectively reviewed. Of those, 95 had upper GI bleeding. One-way analysis of variance was applied to blood test variables comparing patients with and without upper GI bleeding. Logistic regression analysis was applied to detect the association of blood test parameters with upper GI bleeding, and receiver-operator characteristics were applied to establish threshold values. White blood cell count (WBC), platelet (Plt) count, and blood urea nitrogen (BUN) levels were higher, and hemoglobin (Hb) and albumin (Alb) levels were lower in patients with upper GI bleeding. Logistic regression analysis showed that low Hb was significantly associated with upper GI bleeding and a Hb value of 10.8 g/dl was established as the threshold for the diagnosis. In patients with upper GI bleeding, WBC, Plt count, and BUN levels were higher and Hb and Alb levels were reduced. Hb at 10.8 g/dl was established as a threshold value to detect upper GI bleeding. PMID:27588176

  13. Dual targeted poplar ferredoxin NADP(+) oxidoreductase interacts with hemoglobin 1.

    PubMed

    Jokipii-Lukkari, Soile; Kastaniotis, Alexander J; Parkash, Vimal; Sundström, Robin; Leiva-Eriksson, Nélida; Nymalm, Yvonne; Blokhina, Olga; Kukkola, Eija; Fagerstedt, Kurt V; Salminen, Tiina A; Läärä, Esa; Bülow, Leif; Ohlmeier, Steffen; Hiltunen, J Kalervo; Kallio, Pauli T; Häggman, Hely

    2016-06-01

    Previous reports have connected non-symbiotic and truncated hemoglobins (Hbs) to metabolism of nitric oxide (NO), an important signalling molecule involved in wood formation. We have studied the capability of poplar (Populus tremula × tremuloides) Hbs PttHb1 and PttTrHb proteins alone or with a flavin-protein reductase to relieve NO cytotoxicity in living cells. Complementation tests in a Hb-deficient, NO-sensitive yeast (Saccharomyces cerevisiae) Δyhb1 mutant showed that neither PttHb1 nor PttTrHb alone protected cells against NO. To study the ability of Hbs to interact with a reductase, ferredoxin NADP(+) oxidoreductase PtthFNR was characterized by sequencing and proteomics. To date, by far the greatest number of the known dual-targeted plant proteins are directed to chloroplasts and mitochondria. We discovered a novel variant of hFNR that lacks the plastid presequence and resides in cytosol. The coexpression of PttHb1 and PtthFNR partially restored NO resistance of the yeast Δyhb1 mutant, whereas PttTrHb coexpressed with PtthFNR failed to rescue growth. YFP fusion proteins confirmed the interaction between PttHb1 and PtthFNR in plant cells. The structural modelling results indicate that PttHb1 and PtthFNR are able to interact as NO dioxygenase. This is the first report on dual targeting of central plant enzyme FNR to plastids and cytosol. PMID:27095407

  14. Severe central nervous system thrombotic events in hemoglobin Sabine patient.

    PubMed

    Pavlovic, Sonja; Kuzmanovic, Milos; Urosevic, Jelena; Poznanic, Jelena; Zoranovic, Tamara; Djordjevic, Valentina; Rasovic, Nada; Bunjevacki, Gordana; Cvorkov-Drazic, Milica; Colovic, Milica

    2004-01-01

    Hemoglobin (Hb) Sabine is a rare, unstable Hb variant resulting from the point mutation in codon 91 (CTG --> CCG) of beta-globin gene. We report a case of Hb Sabine patient with mild hemolytic anemia, unusually high Hb F level and severe central nervous system thrombotic disturbances. We have tried to elucidate possible genetic background of this unusual Hb Sabine phenotype. Extremely high level of Hb F and rather mild anemia in our patient could be partially explained by the presence of G gamma Xmn I polymorphism. This case of Hb Sabine, unlike all other reported to date, shows extremely severe thromboembolic complications. It is our opinion that the hypercoagulable state described in thalassemia is not the only factor responsible for this specific clinical state. The presence of MTHFR C677T mutation in heterozygous state found in our patient and unstable Hb Sabine molecules could contribute to development of thromboembolic phenomena. However, it remains unclear whether other factors participate in pathogenesis of the disease. In this paper we emphasize different genetic background of father and son both affected with Hb Sabine, but with markedly different severity of the disease.

  15. Noninvasive in vivo monitoring of total blood hemoglobin

    NASA Astrophysics Data System (ADS)

    Wuori, Edward; Gmitter, Mary

    2003-07-01

    Blood hemoglobin (Hb) level is an important health parameter for a large segment of the population. Low Hb can indicate anemia due to chemotherapy, HIV, alcoholism, internal bleeding or other blood loss. There is a great need for noninvasive Hb measurement. A total blood Hb measurement method is shown which does not disturb the subject's skin. Results were obtained using MinforMed's noninvasive blood analyzer prototype (patent pending). A light is shined onto a body part, through the skin, engaging the blood. The emerging light is analyzed for Hb's signature strength in the visible and infrared ranges. Orthogonal decomposition methods are used to extract the Hb data from the complete spectrum. Results were compared to a laboratory-grade instrument that uses a drop of blood. A Hb range from 11 g/dL through 19 g/dL shows excellent correlation, r2=0.97. Other characteristics of the complete spectrum give indication of additional blood analytes, most notably bilirubin and water. Initial results are also shown indicating how light scattering varies with Hb concentration. Approximate residual skin and tissue spectrum is found by removing the spectral signature of the four Hb components (oxy-Hb, deoxy-Hb, carboxy-Hb and met-Hb) from the complete spectrum. This procedure yields the least squares concentrations of the individual Hb components. An SBIR grant from NIH is currently in progress on related work.

  16. Inherited hemoglobin disorders in an Afro-Amazonian community: Saracura

    PubMed Central

    Cardoso, Greice Lemos; Takanashi, Silvania Yukiko Lins; Guerreiro, João Farias

    2012-01-01

    The most common hemoglobinopathies, viz, hemoglobins S and C, and α- and β-thalassemias, were investigated through the molecular screening of 116 subjects from the community of Saracura, comprising fugitive African slaves from farms of the municipality of Santarém, in the west of Pará State, Brazilian Amazon. The observed frequency of the HBB*S gene (0.9%) was significantly lower than that encountered in other Afro-derived communities in the region. Concomitantly, the absence of the HBB*C allele has been reported for most of the Afro-Amazonian communities thus far studied. As remnant populations of quilombos are generally small, the heterogeneous distribution of HBB*S and HBB*C alleles among them is probably due to genetic drift and/or founder effect. The observed frequency of 3.7 kb deletion in Saracura (8.5%) was consistent with the African origin of the population, with a certain degree of local differentiation and admixture with individuals of Caucasian ancestry, placed in evidence by the occurrence of - -(MED) deletion (1.2%), a common mutation in Mediterranean regions. As regards β-thalassemia, among the seven different mutations found in Saracura, three βo and two β+ mutations were of Mediterranean origin, and two β+ of African. Thus, only 28% of the local β-thalassemia mutations found in Saracura were of African origin. PMID:23055791

  17. Association of Hemoglobin Concentration With Total and Cause-Specific Mortality in a Cohort of Postmenopausal Women.

    PubMed

    Kabat, Geoffrey C; Kim, Mimi Y; Verma, Amit K; Manson, JoAnn E; Lessin, Lawrence S; Kamensky, Victor; Lin, Juan; Wassertheil-Smoller, Sylvia; Rohan, Thomas E

    2016-05-15

    Anemia and low and high levels of hemoglobin have been associated with increased mortality and morbidity. However, most studies have measured hemoglobin at only 1 time point, and few studies have considered possible reverse causation. We used data from the Women's Health Initiative, in which baseline hemoglobin was measured in 160,081 postmenopausal women and year 3 hemoglobin was measured in 75,658 participants, to examine the associations of hemoglobin concentration with total mortality, coronary heart disease mortality, and cancer mortality. Women were enrolled from 1993 to 1998 and followed for a median of 16 years. Cox proportional hazards models were used to estimate the relative mortality hazards associated with deciles of baseline hemoglobin and the mean of baseline + year 3 hemoglobin. Both low and high deciles of baseline hemoglobin were positively associated with all 3 outcomes in the total cohort. In analyses restricted to women with 2 measurements, a low mean hemoglobin level was robustly and positively associated with all 3 outcomes, after exclusion of the early years of follow-up. High mean hemoglobin was also associated with increased risk of total mortality, whereas associations with heart disease mortality and cancer mortality were weaker and inconsistent. Our results provide evidence that low and high levels of hemoglobin are associated with increased risk of mortality in otherwise healthy women. PMID:27076671

  18. Binding of hydroxylated single-walled carbon nanotubes to two hemoproteins, hemoglobin and myoglobin.

    PubMed

    Wang, Yan-Qing; Zhang, Hong-Mei; Cao, Jian

    2014-12-01

    Herein, we studied the binding interactions between hydroxylated single-walled carbon nanotubes and hemoglobin and myoglobin by the use of multi-spectral techniques and molecular modeling. The ultraviolet-vis absorbance and circular dichroism spectral results indicated that the binding interactions existed between hydroxylated single-walled carbon nanotubes and hemoglobin/myoglobin. These binding interactions partially affected the soret/heme bands of hemoglobin and myoglobin. The secondary structures of hemoproteins were partially destroyed by hydroxylated single-walled carbon nanotubes. Fluorescence studies suggested that the complexes formed between hydroxylated single-walled carbon nanotubes and hemoglobin/myoglobin by hydrogen bonding, hydrophobic, and π-π stacking interactions. In addition, molecular modeling analysis well supported the experimental results.

  19. Oxygen binding properties of hemoglobin from the white rhinoceros (beta 2-GLU) and the tapir.

    PubMed

    Baumann, R; Mazur, G; Braunitzer, G

    1984-04-01

    The beta-chain of rhinoceros hemoglobin contains glutamic acid at position beta 2, and important site for the binding of organic phosphates. We have investigated the oxygen binding properties of this hemoglobin and its interaction with ATP, 2,3-diphosphoglycerate, CO2 and chloride. The results show that the presence of GLU at position beta 2 nearly abolishes the effect of organic phosphates and CO2, whereas the oxygen-linked binding of chloride is not affected. Thus rhinoceros hemoglobin has only protons and chloride anions as major allosteric effectors for the control of its oxygen affinity. From the results obtained with hemoglobin solutions it can be calculated that the blood oxygen affinity of the rhinoceros must be rather high with a P50 of about 20 torr at pH 7.4 and 37 degrees C, which conforms with observations obtained for other large mammals.

  20. Towards erythropoietin equations that estimate oxygen delivery rather than static hemoglobin targets.

    PubMed

    Diskin, Charles J

    2012-01-01

    Although we have known since the 19th century that oxygen tension affects erythrocyte production, we have only recently begun to understand many subtleties of erythropoietin physiology. The unanticipated increase in mortality associated with erythropoietin use found in recent randomized studies is prompting a reassessment of static hemoglobin targets. Hemoglobin levels in dialysis patients do not correlate with endogenous erythropoietin production and may be related to differences in oxygen delivery resulting from shifts in the oxygen-hemoglobin dissociation curve. The time may have arrived to develop more physiologic targets such as oxygen delivery that would mimic the natural response to hypoxia. There are several equations that already exist that can compensate for the effects of the concentration of inorganic and organic phosphates as well as pH, carbon dioxide, and temperature on the delivery of oxygen. However, since the shape and dispersion of the oxygen-hemoglobin dissociation curve may actually change in different disease states, more work is needed.

  1. Substitution of Fingertip Blood for Venous Blood in the Measurement of Hematocrit and Hemoglobin Following Exercise

    ERIC Educational Resources Information Center

    Fahey, Thomas D.; And Others

    1977-01-01

    Results from comparative testing indicate that fingertip blood is a valid indicator of antecubital venous hematocrit (hct) and hemoglobin (hgb), and that hct ratios determined on the Coulter counter are comparable to those found by the microhematocrit method. (MB)

  2. Effects of Iron Supplementation and Activity on Serum Iron Depletion and Hemoglobin Levels in Female Athletes

    ERIC Educational Resources Information Center

    Cooter, G. Rankin; Mowbray, Kathy W.

    1978-01-01

    Research revealed that a four-month basketball training program did not significantly alter serum iron, total iron binding capacity, hemoglobin, and percent saturation levels in female basketball athletes. (JD)

  3. Glycosylated hemoglobin determination from capillary blood samples. Utility in an epidemiologic survey of diabetes.

    PubMed

    Ferrell, R E; Hanis, C L; Aguilar, L; Tulloch, B; Garcia, C; Schull, W J

    1984-02-01

    Total glycosylated hemoglobin was measured from capillary blood specimens obtained from a sample of 1880 individuals of Mexican-American ancestry residing in Starr County, Texas, between January 1981 and February 1982, as part of an epidemiologic survey to assess the prevalence of noninsulin-dependent diabetes mellitus (Type II). No significant difference was found between males and females. Diabetics were found to have significantly higher levels of glycosylated hemoglobin than nondiabetics. However, among diabetics, there was no significant difference between newly diagnosed and known diabetics, and known diabetics taking medication did not differ significantly from those not taking medication. An analysis of the specificity and sensitivity of glycosylated hemoglobin, fasting blood glucose, and casual blood glucose determinations as screening devices in a survey of diabetes prevalence reveals that glycosylated hemoglobin is superior to casual blood glucose determination. The conditions under which various screening devices might be more effective are discussed. PMID:6695895

  4. Assessment of hemoglobin dynamics in traumatic bruises using temperature depth profiling

    NASA Astrophysics Data System (ADS)

    Vidovič, Luka; Milanič, Matija; Majaron, Boris

    2013-11-01

    Perceived color of traumatic bruise depends strongly on depth of the spilled blood, natural skin tone, ambient light conditions, etc., which prevents an accurate and reliable determination of the time of the injury. Pulsed photothermal radiometry (PPTR) allows noninvasive determination of the laser-induced temperature depth profile in human skin. We have applied this technique to characterize dynamics of extravasated hemoglobin in the bruise. Next, we use simple model of mass diffusion and biochemical transformation kinetics to simulate bruise dynamics. By applying Monte Carlo simulation of laser energy deposition, comparison with measured temperature profiles is possible. However, parameters of the model were previously not determined directly. Instead, biologically plausible values were assumed. We show how temperature depth profiling enables accurate monitoring of hemoglobin diffusion and degradation. Parameters of the model, hemoglobin mass diffusivity, hemoglobin degradation time, and skin geometry, can be estimated rather accurately. Derivation of bruise evolution parameters will be a valuable addition to existing bruise age determination techniques.

  5. Fetal hemoglobin in sickle cell anemia: molecular characterization of the unusually high fetal hemoglobin phenotype in African Americans.

    PubMed

    Akinsheye, Idowu; Solovieff, Nadia; Ngo, Duyen; Malek, Anita; Sebastiani, Paola; Steinberg, Martin H; Chui, David H K

    2012-02-01

    Fetal hemoglobin (HbF) is a major modifier of disease severity in sickle cell anemia (SCA). Three major HbF quantitative trait loci (QTL) are known: the Xmn I site upstream of (G)γ- globin gene (HBG2) on chromosome 11p15, BCL11A on chromosome 2p16, and HBS1L-MYB intergenic polymorphism (HMIP) on chromosome 6q23. However, the roles of these QTLs in patients with SCA with uncharacteristically high HbF are not known. We studied 20 African American patients with SCA with markedly elevated HbF (mean 17.2%). They had significantly higher minor allele frequencies (MAF) in two HbF QTLs, BCL11A, and HMIP, compared with those with low HbF. A 3-bp (TAC) deletion in complete linkage disequilibrium (LD) with the minor allele of rs9399137 in HMIP was also present significantly more often in these patients. To further explore other genetic loci that might be responsible for this high HbF, we sequenced a 14.1 kb DNA fragment between the (A)γ-(HBG1) and δ-globin genes (HBD). Thirty-eight SNPs were found. Four SNPs had significantly higher major allele frequencies in the unusually high HbF group. In silico analyses of these four polymorphisms predicted alteration in transcription factor binding sites in 3.

  6. Inducible heme oxygenase in the kidney: a model for the homeostatic control of hemoglobin catabolism

    PubMed Central

    Pimstone, Neville R.; Engel, Peter; Tenhunen, Raimo; Seitz, Paul T.; Marver, Harvey S.; Schmid, Rudi

    1971-01-01

    We have recently identified and characterized NADPH-dependent microsomal heme oxygenase as the major enzymatic mechanism for the conversion of hemoglobin-heme to bilirubin-IXα in vivo. Enzyme activity is highest in tissues normally involved in red cell breakdown, that is, spleen, liver, and bone marrow, but it usually is negligible in the kidney. However, renal heme oxygenase activity may be transiently increased 30- to 100-fold following hemoglobinemia that exceeded the plasma haptoglobin-binding capacity and consequently resulted in hemoglobinuria. Maximal stimulation of enzyme activity in rats is reached 6-16 hr following a single intravenous injection of 30 mg of hemoglobin per 100 g body weight; activity returns to basal levels after about 48 hr. At peak level, total enzyme activity in the kidneys exceeds that of the spleen or liver. Cyclohexamide, puromycin, or actinomycin D, given just before, or within a few hours after, a single intravenous injection of hemoglobin minimizes or prevents the rise in renal enzyme activity; this suggests that the increase in enzyme activity is dependent on continued synthesis of ribonucleic acid and protein. The apparent biological half-life of renal heme oxygenase is about 6 hr. These observations indicate that functional adaptation of renal heme oxygenase activity reflects enzyme induction either directly or indirectly by the substrate, hemoglobin. Filtered rather than plasma hemoglobin appears to regulate renal heme oxygenase activity. Thus, stabilization of plasma hemoglobin in its tetrameric form with bis (N-maleimidomethyl) ether, which diminishes its glomerular filtration and retards it plasma clearance, results in reduced enzyme stimulation in the kidney, but enhances its activity in the liver. These findings suggest that the enzyme is localized in the tubular epithelial cells rather than in the glomeruli and is activated by luminal hemoglobin. Direct support for this concept was obtained by the demonstration of heme

  7. Capillary zone electrophoresis: an additional technique for the identification of hemoglobin variants.

    PubMed

    Lin, C; Cotton, F; Fontaine, B; Gulbis, B; Janssens, J; Vertongen, F

    1999-05-01

    Two capillary zone electrophoresis kits (Hb A2 and Hb A1c) were tested for confirmation and identification of hemoglobin variants. The capillary zone electrophoresis experiments were performed at pH 4.7 (Hb A1c kit) and 8.7 (Hb A2 kit) in a 24 cm uncoated fused silica capillary tube (25 microm I.D.). Normal hemoglobins and common hemoglobin variants, including Hbs S, D-Punjab, C, E, O-Arab, and G-Philadelphia, were successfully separated by both methods within a few minutes. Both systems provided completely different elution profiles of normal and abnormal hemoglobin fractions tested and were complementary. The inter-assay coefficient of variations of the migration times of hemoglobin variants were less than 1.0 and 1.3% by the Hb A2 and Hb A1c, respectively. This permits a higher resolution of some hemoglobin variants in low concentrations, like Hb S in newborns, compared with conventional electrophoresis methods. The present capillary zone electrophoresis methods are sensitive, rapid, not labor intensive, and highly selective for the separation of hemoglobin variants. Combination of both methods with some conventional methods, such as isoelectrofocusing, allows identification of Hbs C, E, O-Arab, S, and D-Punjab, as well as their quantification. We have demonstrated that the conventional electrophoresis methods (electrophoresis at pH 6.5 in citrate agar gel and electrophoresis at pH 8.6 on cellulose acetate) can be advantageously replaced by the present capillary zone electrophoresis methods in a clinical laboratory practice for the detection and quantification of hemoglobin variants. PMID:10335978

  8. Hemoglobin and hip fracture risk in older non-Hispanic white adults1

    PubMed Central

    Looker, Anne C.

    2016-01-01

    Purpose The few studies to date that have examined the relationship between hemoglobin and fracture risk have focused on low hemoglobin values. The present study examined hip fracture risk across the hemoglobin distribution in older non-Hispanic white adults from the third National Health and Nutrition Examination Survey (NHANES III, 1988–1994). Methods Hemoglobin was measured using a Coulter S-plus Jr.® (Coulter Electronics, Hialeah, FL) in 2122 non-Hispanic whites age 65 years and older. Hip fracture cases were identified using linked Medicare and mortality records obtained through 2007. Cox proportional hazards models were used to assess the best-fitting model and to estimate the hazards ratio (HR) for hip fracture by hemoglobin decile before and after adjusting for selected confounders. Results There were 239 hip fracture cases in the analytic sample. The best fitting model was quadratic. When compared to values in the middle of the distribution, those with hemoglobin in the lowest and highest deciles had increased hip fracture risk (HRlowest decile =2.96, 95% CI 1.44–6.08; HRhighest decile = 2.06, 95% CI 1.09–3.92) after adjusting for age and sex. Both HRs remained significant after adjusting for additional confounders (HRlowest decile =2.24, 95% CI 1.09–3.92; HRhighest decile = 2.37, 95% CI 1.35–4.16). Conclusions Both low and high hemoglobin values were associated with increased hip fracture risk. The mechanism underlying the relationship is not clear, but there was some suggestion that it may differ for low versus high hemoglobin. PMID:24938506

  9. Association of hemoglobin with ankle-brachial index in general population

    PubMed Central

    Chenglong, Zhang; Jing, Lei; Xia, Ke; Yang, Tianlun

    2016-01-01

    OBJECTIVES: Previous studies have demonstrated that both low and high hemoglobin concentrations are predictive of adverse cardiovascular outcomes in various populations. However, an association of hemoglobin with the ankle-brachial index, which is widely used as a screening test for peripheral arterial disease, has not yet been identified. METHODS: We examined 786 subjects (236 women and 550 men) who received routine physical check-ups. The ankle-brachial index and several hematological parameters, including the hemoglobin level, hematocrit and red blood cell count and other demographic and biochemical characteristics were collected. Univariate and multivariate linear regression analyses were performed to assess the relationships between the ankle-brachial index and the independent determinants. Receiver operating characteristic curve analysis was conducted to calculate the cut-off level of hemoglobin for a relatively low ankle-brachial index (less than 20% of all subjects, which was 1.02). RESULTS: The hemoglobin level, hematocrit and red blood cell count were correlated with the ankle-brachial index in the males (r=-0.274, r=-0.224 and r=-0.273, respectively, p<0.001 for all), but these associations were not significant in the females. Multivariate linear regression analysis revealed that the independent determinants of the ankle-brachial index included age, total cholesterol, high-density lipoprotein cholesterol and the white blood cell count for the females and age, hypertension, total cholesterol and hemoglobin (β=-0.001, p<0.001) for the males after adjusting for confounding factors. Receiver operating characteristic curve analysis revealed that the cut-off level of hemoglobin for predicting a low ankle-brachial index was 156.5 g/L in the males. CONCLUSIONS: A high hemoglobin concentration was independently correlated with a low ankle-brachial index in the healthy males, indicating that an elevation in this level may be associated with an increased

  10. The hemoglobin system of the brown moray Gymnothorax unicolor: structure/function relationships.

    PubMed

    Tamburrini, M; Verde, C; Olianas, A; Giardina, B; Corda, M; Sanna, M T; Fais, A; Deiana, A M; di Prisco, G; Pellegrini, M

    2001-07-01

    The Gymnothorax unicolor hemoglobin system is characterized by two components, called cathodic and anodic on the basis of their isoelectric point, which were separated by ion-exchange chromatography. The oxygen-binding properties of the purified components were studied in the absence and presence of chloride and/or GTP or ATP in the pH range 6.5-8.0. Stripped cathodic hemoglobin showed a small reverse Bohr effect, high oxygen affinity, and low co-operativity; the addition of chloride only caused a small decrease in oxygen affinity. In the presence of GTP or ATP, the oxygen affinity was dramatically reduced, the co-operativity increased, and the reverse Bohr effect abolished. Stripped anodic hemoglobin is characterized by both low oxygen affinity and co-operativity, and displayed a normal Bohr effect; the addition of chloride increased co-operativity, whereas ATP and GTP significantly modulated oxygen affinity at acidic pH values, enhancing the Bohr effect and giving rise to the Root effect. The complete amino-acid sequences of the alpha and beta chains of both hemoglobins were established; the molecular basis of the functional properties of the hemoglobins is discussed in the light of the primary structure and compared with those of other fish hemoglobins.

  11. Comparison of two iron supplementation methods on Hemoglobin level and Menstrual Bleeding in Tabriz students

    PubMed Central

    Bani, S; Hassanpour- Siahestalkhi, A; Hassanpour, Sh; Mommad- Alizadeh- Charandabi, S; Mirghafourvand, M; Javadzadeh, Y

    2014-01-01

    Background Iron deficiency anemia is a global health problem, and approximately 50% of anemia is caused by iron deficiency. According to studies, iron supplementation in young females improves iron status by increasing concentration of hemoglobin. To compare of prescribing two methods of iron supplementation administered either on a weekly basis or during menstruation, on hemoglobin level and menstrual blood¸ this double blind Randomized clinical trial study was carried out among female students in Tabriz, Iran. Materials and Methods In this double-blind randomized clinical trial, 150 female students allocated randomly in two groups. (75 students took an iron tablet weekly and 75 students took an iron tablet for first four days during their menstruation cycle for 16 weeks). Before and after intervention, the level of hemoglobin was measured and Higham chart was completed by participants in each group. Chi-square, independent t-Test, paired t-Test and ANCOVA were used for data analysis. Results There was no significant difference between two groups in terms of demographic characteristics, hemoglobin level and amount of menstrual bleeding before and after intervention (p>0.05). Taking iron supplement increased significantly the level of hemoglobin in each group (p<0.001). However, there was no significant difference in amount of menstrual bleeding (p>0.05) when comparing the data before and after intervention in each group. Conclusion The two iron supplementation methods (menstrual bleeding period and weekly) have similar results on Hemoglobin level and menstrual bleeding. PMID:24734158

  12. Investigation of Hemoglobin/Gold Nanoparticle Heterolayer on Micro-Gap for Electrochemical Biosensor Application

    PubMed Central

    Lee, Taek; Kim, Tae-Hyung; Yoon, Jinho; Chung, Yong-Ho; Lee, Ji Young; Choi, Jeong-Woo

    2016-01-01

    In the present study, we fabricated a hemoglobin/gold nanoparticle (Hb/GNP) heterolayer immobilized on the Au micro-gap to confirm H2O2 detection with a signal-enhancement effect. The hemoglobin which contained the heme group catalyzed the reduction of H2O2. To facilitate the electron transfer between hemoglobin and Au micro-gap electrode, a gold nanoparticle was introduced. The Au micro-gap electrode that has gap size of 5 µm was fabricated by conventional photolithographic technique to locate working and counter electrodes oppositely in a single chip for the signal sensitivity and reliability. The hemoglobin was self-assembled onto the Au surface via chemical linker 6-mercaptohexanoic acid (6-MHA). Then, the gold nanoparticles were adsorbed onto hemoglobin/6-MHA heterolayers by the layer-by-layer (LbL) method. The fabrication of the Hb/GNP heterolayer was confirmed by atomic force microscopy (AFM) and surface-enhanced Raman spectroscopy (SERS). The redox property and H2O2 detection of Hb/GNP on the micro-gap electrode was investigated by a cyclic voltammetry (CV) experiment. Taken together, the present results show that the electrochemical signal-enhancement effect of a hemoglobin/nanoparticle heterolayer was well confirmed on the micro-scale electrode for biosensor applications. PMID:27171089

  13. A spectroscopic study on the interaction between gold nanoparticles and hemoglobin

    SciTech Connect

    Garabagiu, Sorina

    2011-12-15

    Highlights: Black-Right-Pointing-Pointer The interaction was studied using UV-vis and fluorescence spectroscopy. Black-Right-Pointing-Pointer Gold nanoparticles quench the fluorescence emission of hemoglobin solution. Black-Right-Pointing-Pointer The binding and thermodynamic constants were calculated. Black-Right-Pointing-Pointer Major impact: electrochemical applications of the complex onto a substrate. -- Abstract: The interaction between horse hemoglobin and gold nanoparticles was studied using optical spectroscopy. UV-vis and fluorescence spectra show that a spontaneous binding process occurred between hemoglobin and gold nanoparticles. The Soret band of hemoglobin in the presence of gold nanoparticles does not show significant changes, which proves that the protein retained its biological function. A shift to longer wavelengths appears in the plasmonic band of gold nanoparticles upon the attachment of hemoglobin molecules. Gold nanoparticles quench the fluorescence emission of tryptophan residues in the structure of hemoglobin. The Stern-Volmer quenching constant, the binding constant and the number of binding sites were also calculated. Thermodynamic parameters indicate that the binding was mainly due to hydrophobic interactions.

  14. Increased hemoglobin-oxygen affinity ameliorates bleomycin-induced hypoxemia and pulmonary fibrosis.

    PubMed

    Geng, Xin; Dufu, Kobina; Hutchaleelaha, Athiwat; Xu, Qing; Li, Zhe; Li, Chien-Ming; Patel, Mira P; Vlahakis, Nicholas; Lehrer-Graiwer, Josh; Oksenberg, Donna

    2016-09-01

    Although exertional dyspnea and worsening hypoxia are hallmark clinical features of idiopathic pulmonary fibrosis (IPF), no drug currently available could treat them. GBT1118 is a novel orally bioavailable small molecule that binds to hemoglobin and produces a concentration-dependent left shift of the oxygen-hemoglobin dissociation curve with subsequent increase in hemoglobin-oxygen affinity and arterial oxygen loading. To assess whether pharmacological modification of hemoglobin-oxygen affinity could ameliorate hypoxemia associated with lung fibrosis, we evaluated GBT1118 in a bleomycin-induced mouse model of hypoxemia and fibrosis. After pulmonary fibrosis and hypoxemia were induced, GBT1118 was administered for eight consecutive days. Hypoxemia was determined by monitoring arterial oxygen saturation, while the severity of pulmonary fibrosis was assessed by histopathological evaluation and determination of collagen and leukocyte levels in bronchoalveolar lavage fluid. We found that hemoglobin modification by GBT1118 had strong antihypoxemic therapeutic effects with improved arterial oxygen saturation to near normal level. Moreover, GBT1118 treatment significantly attenuated bleomycin-induced lung fibrosis, collagen accumulation, body weight loss, and leukocyte infiltration. This study is the first to suggest the beneficial effects of hemoglobin modification in fibrotic lungs and offers a promising and novel therapeutic strategy for the treatment of hypoxemia associated with chronic fibrotic lung disorders in human, including IPF. PMID:27624688

  15. EHMT1 and EHMT2 inhibition induces fetal hemoglobin expression

    PubMed Central

    Renneville, Aline; Van Galen, Peter; Canver, Matthew C.; McConkey, Marie; Krill-Burger, John M.; Dorfman, David M.; Holson, Edward B.; Bernstein, Bradley E.; Orkin, Stuart H.; Bauer, Daniel E.

    2015-01-01

    Fetal hemoglobin (HbF, α2γ2) induction is a well-validated strategy for sickle cell disease (SCD) treatment. Using a small-molecule screen, we found that UNC0638, a selective inhibitor of EHMT1 and EHMT2 histone methyltransferases, induces γ-globin expression. EHMT1/2 catalyze mono- and dimethylation of lysine 9 on histone 3 (H3K9), raising the possibility that H3K9Me2, a repressive chromatin mark, plays a role in silencing γ-globin expression. In primary human adult erythroid cells, UNC0638 and EHMT1 or EHMT2 short hairpin RNA–mediated knockdown significantly increased γ-globin expression, HbF synthesis, and the percentage of cells expressing HbF. At effective concentrations, UNC0638 did not alter cell morphology, proliferation, or erythroid differentiation of primary human CD34+ hematopoietic stem and progenitor cells in culture ex vivo. In murine erythroleukemia cells, UNC0638 and Ehmt2 CRISPR/Cas9-mediated knockout both led to a marked increase in expression of embryonic β-globin genes Hbb-εy and Hbb-βh1. In primary human adult erythroblasts, chromatin immunoprecipitation followed by sequencing analysis revealed that UNC0638 treatment leads to genome-wide depletion in H3K9Me2 and a concomitant increase in the activating mark H3K9Ac, which was especially pronounced at the γ-globin gene region. In RNA-sequencing analysis of erythroblasts, γ-globin genes were among the most significantly upregulated genes by UNC0638. Further increase in γ-globin expression in primary human adult erythroid cells was achieved by combining EHMT1/2 inhibition with the histone deacetylase inhibitor entinostat or hypomethylating agent decitabine. Our data provide genetic and pharmacologic evidence that EHMT1 and EHMT2 are epigenetic regulators involved in γ-globin repression and represent a novel therapeutic target for SCD. PMID:26320100

  16. Hemoglobin enhances tissue factor expression on human malignant cells.

    PubMed

    Siddiqui, F A; Amirkhosravi, A; Amaya, M; Meyer, T; Biggerstaff, J; Desai, H; Francis, J L

    2001-04-01

    Tissue Factor (TF) is a transmembrane glycoprotein that complexes with factor VII/activated factor VII to initiate blood coagulation. TF may be expressed on the surface of various cells including monocytes and endothelial cells. Over-expression of TF in human tumor cell lines promotes metastasis. We recently showed that hemoglobin (Hb) forms a specific complex with TF purified from human malignant melanoma cells and enhances its procoagulant activity (PCA). To further study this interaction, we examined the effect of Hb on the expression of TF on human malignant (TF+) cells and KG1 myeloid leukemia (TF-) cells. Human melanoma A375 and J82 bladder carcinoma cells, which express TF at moderate and relatively high levels, respectively, were incubated with varying concentrations (0-1.5 mg/ml) of Hb. After washing, cells were analyzed for Hb binding and TF expression using flow cytometry and confocal microscopy. Hb bound to the cells in a concentration-dependent manner, and increased both TF expression and PCA. The human A375 malignant melanoma cells incubated with Hb (1 mg/ml) expressed up to six times more TF antigen than cells without Hb. This increase in TF expression and PCA of intact cells incubated with Hb was significantly inhibited by cycloheximide at a concentration of 10 microg/ml (P < 0.01). An increase in total cellular TF antigen content was demonstrated by specific immunoassay. In contrast, Hb (5 mg/ml) did not induce TF expression and PCA on KG1 cells as determined by flow cytometry and TF (FXAA) activity. We conclude that Hb specifically binds to TF-bearing malignant cells and increases their PCA. This effect seems to be at least partly due to de novo synthesis of TF and increased surface expression. However, the exact mechanism by which Hb binds and upregulates TF expression remains to be determined.

  17. The pathophysiology of extracellular hemoglobin associated with enhanced oxidative reactions

    PubMed Central

    Rifkind, Joseph M.; Mohanty, Joy G.; Nagababu, Enika

    2015-01-01

    Hemoglobin (Hb) continuously undergoes autoxidation producing superoxide which dismutates into hydrogen peroxide (H2O2) and is a potential source for subsequent oxidative reactions. Autoxidation is most pronounced under hypoxic conditions in the microcirculation and for unstable dimers formed at reduced Hb concentrations. In the red blood cell (RBC), oxidative reactions are inhibited by an extensive antioxidant system. For extracellular Hb, whether from hemolysis of RBCs and/or the infusion of Hb-based blood substitutes, the oxidative reactions are not completely neutralized by the available antioxidant system. Un-neutralized H2O2 oxidizes ferrous and ferric Hbs to Fe(IV)-ferrylHb and OxyferrylHb, respectively. FerrylHb further reacts with H2O2 producing heme degradation products and free iron. OxyferrylHb, in addition to Fe(IV) contains a free radical that can undergo additional oxidative reactions. Fe(III)Hb produced during Hb autoxidation also readily releases heme, an additional source for oxidative stress. These oxidation products are a potential source for oxidative reactions in the plasma, but to a greater extent when the lower molecular weight Hb dimers are taken up into cells and tissues. Heme and oxyferryl have been shown to have a proinflammatory effect further increasing their potential for oxidative stress. These oxidative reactions contribute to a number of pathological situations including atherosclerosis, kidney malfunction, sickle cell disease, and malaria. The toxic effects of extracellular Hb are of particular concern with hemolytic anemia where there is an increase in hemolysis. Hemolysis is further exacerbated in various diseases and their treatments. Blood transfusions are required whenever there is an appreciable decrease in RBCs due to hemolysis or blood loss. It is, therefore, essential that the transfused blood, whether stored RBCs or the blood obtained by an Autologous Blood Recovery System from the patient, do not further increase

  18. Relationship between periodontal status and levels of glycated hemoglobin.

    PubMed

    Morita, I; Inagaki, K; Nakamura, F; Noguchi, T; Matsubara, T; Yoshii, S; Nakagaki, H; Mizuno, K; Sheiham, A; Sabbah, W

    2012-02-01

    The objective of this study was to assess whether there is a bi-directional relationship between periodontal status and diabetes. Study 1 included 5,856 people without periodontal pockets of ≥ 4 mm at baseline. Relative risk was estimated for the 5-year incidence of periodontal pockets of ≥ 4 mm (CPI scores 3 and 4, with the CPI probe), in individuals with glycated hemoglobin (HbA1c) levels of ≥ 6.5% at baseline. Study 2 included 6,125 people with HbA1c < 6.5% at baseline. The relative risk was assessed for elevation of HbA1c levels in 5 years, with baseline periodontal status, assessed by CPI. Relative risk of developing a periodontal pocket was 1.17 (p = 0.038) times greater in those with HbA1c of ≥ 6.5% at baseline, adjusted for body mass index (BMI), smoking status, sex, and age. Relative risks for having HbA1c ≥ 6.5% at 5-year follow-up in groups with periodontal pockets of 4 to 5 mm and ≥ 6 mm at baseline were 2.47 (p = 0.122) and 3.45 (p = 0.037), respectively, adjusted for BMI, alcohol consumption, smoking status, sex, and age. The risk of developing periodontal disease was associated with levels of HbA1c, and the risk of elevations of HbA1c was associated with developing periodontal pockets of more than 4 mm. PMID:22157098

  19. [Glycosylated hemoglobin (HbA1) in pregnancy].

    PubMed

    Partida Hernández, G; Gómez García, A; Arreola Ortíz, J F

    2000-10-01

    The life style, genetic predisposition and metabolic changes occurring during pregnancy can modify the percent value of glycated hemoglobins (HbA1 and HbA1c). In addition, research papers from different laboratories in the world have reported contradictory results on this respect. The purpose of this trial was to know the percent value of HbA1 in healthy women, during the different trimesters of pregnancy. 206 pregnant (E) healthy women who came over for prenatal control to UMF No 80 IMSS in Morelia, Michoacan with no previous history of Diabetes mellitus or Essential Hypertension were classified by trimesters of pregnancy (1T, 2T, 3T) and chronological age (I, 18-24; 11, 25-30; III, 31-35 years). Their chronological and gestational ages, weight, height, body mass index and parity were recorded. % HbA1 (ion exchange chromatography) was determined on each patient. Control group was formed by 187 non pregnant healthy women (NE) chosen with same criterion that pregnant women. % HbA1 was lower in E during pregnancy (7.11 +/- 1.53 vs 7.78 +/- 1.12%, p < 0.0001) than NE group. % HbA1 in E group was lower in the 1T and 2T than in the 3T (p < 0.001), same situation was observed in 18 to 24 (group I) and 25 to 30 (group II) years old. In the other hand, in E from group II on the 2T the weeks of gestation were correlated with % HbA1 (r = 0.72, p < 0.05). This results show a diminished HbA1 percent in E group with a lower values in the 1T and 2T. Moreover, these results will allow us to know HbA1 appearance in diabetic pregnant women and to evaluate the degree of metabolic control.

  20. Oxygenation properties and isoform diversity of snake hemoglobins.

    PubMed

    Storz, Jay F; Natarajan, Chandrasekhar; Moriyama, Hideaki; Hoffmann, Federico G; Wang, Tobias; Fago, Angela; Malte, Hans; Overgaard, Johannes; Weber, Roy E

    2015-11-01

    Available data suggest that snake hemoglobins (Hbs) are characterized by a combination of unusual structural and functional properties relative to the Hbs of other amniote vertebrates, including oxygenation-linked tetramer-dimer dissociation. However, standardized comparative data are lacking for snake Hbs, and the Hb isoform composition of snake red blood cells has not been systematically characterized. Here we present the results of an integrated analysis of snake Hbs and the underlying α- and β-type globin genes to characterize 1) Hb isoform composition of definitive erythrocytes, and 2) the oxygenation properties of isolated isoforms as well as composite hemolysates. We used species from three families as subjects for experimental studies of Hb function: South American rattlesnake, Crotalus durissus (Viperidae); Indian python, Python molurus (Pythonidae); and yellow-bellied sea snake, Pelamis platura (Elapidae). We analyzed allosteric properties of snake Hbs in terms of the Monod-Wyman-Changeux model and Adair four-step thermodynamic model. Hbs from each of the three species exhibited high intrinsic O2 affinities, low cooperativities, small Bohr factors in the absence of phosphates, and high sensitivities to ATP. Oxygenation properties of the snake Hbs could be explained entirely by allosteric transitions in the quaternary structure of intact tetramers, suggesting that ligation-dependent dissociation of Hb tetramers into αβ-dimers is not a universal feature of snake Hbs. Surprisingly, the major Hb isoform of the South American rattlesnake is homologous to the minor HbD of other amniotes and, contrary to the pattern of Hb isoform differentiation in birds and turtles, exhibits a lower O2 affinity than the HbA isoform. PMID:26354849

  1. Oxygenation properties and isoform diversity of snake hemoglobins.

    PubMed

    Storz, Jay F; Natarajan, Chandrasekhar; Moriyama, Hideaki; Hoffmann, Federico G; Wang, Tobias; Fago, Angela; Malte, Hans; Overgaard, Johannes; Weber, Roy E

    2015-11-01

    Available data suggest that snake hemoglobins (Hbs) are characterized by a combination of unusual structural and functional properties relative to the Hbs of other amniote vertebrates, including oxygenation-linked tetramer-dimer dissociation. However, standardized comparative data are lacking for snake Hbs, and the Hb isoform composition of snake red blood cells has not been systematically characterized. Here we present the results of an integrated analysis of snake Hbs and the underlying α- and β-type globin genes to characterize 1) Hb isoform composition of definitive erythrocytes, and 2) the oxygenation properties of isolated isoforms as well as composite hemolysates. We used species from three families as subjects for experimental studies of Hb function: South American rattlesnake, Crotalus durissus (Viperidae); Indian python, Python molurus (Pythonidae); and yellow-bellied sea snake, Pelamis platura (Elapidae). We analyzed allosteric properties of snake Hbs in terms of the Monod-Wyman-Changeux model and Adair four-step thermodynamic model. Hbs from each of the three species exhibited high intrinsic O2 affinities, low cooperativities, small Bohr factors in the absence of phosphates, and high sensitivities to ATP. Oxygenation properties of the snake Hbs could be explained entirely by allosteric transitions in the quaternary structure of intact tetramers, suggesting that ligation-dependent dissociation of Hb tetramers into αβ-dimers is not a universal feature of snake Hbs. Surprisingly, the major Hb isoform of the South American rattlesnake is homologous to the minor HbD of other amniotes and, contrary to the pattern of Hb isoform differentiation in birds and turtles, exhibits a lower O2 affinity than the HbA isoform.

  2. Hemoglobin enhances tissue factor expression on human malignant cells.

    PubMed

    Siddiqui, F A; Amirkhosravi, A; Amaya, M; Meyer, T; Biggerstaff, J; Desai, H; Francis, J L

    2001-04-01

    Tissue Factor (TF) is a transmembrane glycoprotein that complexes with factor VII/activated factor VII to initiate blood coagulation. TF may be expressed on the surface of various cells including monocytes and endothelial cells. Over-expression of TF in human tumor cell lines promotes metastasis. We recently showed that hemoglobin (Hb) forms a specific complex with TF purified from human malignant melanoma cells and enhances its procoagulant activity (PCA). To further study this interaction, we examined the effect of Hb on the expression of TF on human malignant (TF+) cells and KG1 myeloid leukemia (TF-) cells. Human melanoma A375 and J82 bladder carcinoma cells, which express TF at moderate and relatively high levels, respectively, were incubated with varying concentrations (0-1.5 mg/ml) of Hb. After washing, cells were analyzed for Hb binding and TF expression using flow cytometry and confocal microscopy. Hb bound to the cells in a concentration-dependent manner, and increased both TF expression and PCA. The human A375 malignant melanoma cells incubated with Hb (1 mg/ml) expressed up to six times more TF antigen than cells without Hb. This increase in TF expression and PCA of intact cells incubated with Hb was significantly inhibited by cycloheximide at a concentration of 10 microg/ml (P < 0.01). An increase in total cellular TF antigen content was demonstrated by specific immunoassay. In contrast, Hb (5 mg/ml) did not induce TF expression and PCA on KG1 cells as determined by flow cytometry and TF (FXAA) activity. We conclude that Hb specifically binds to TF-bearing malignant cells and increases their PCA. This effect seems to be at least partly due to de novo synthesis of TF and increased surface expression. However, the exact mechanism by which Hb binds and upregulates TF expression remains to be determined. PMID:11414630

  3. Hemoglobin O2 Saturation with Mild Hypoxia and Microgravity

    NASA Technical Reports Server (NTRS)

    Conkin, J.; Wessel, J. H., III; Norcross, J. R.; Bekdash, O. S.; Abercromby, A. J. F.; Koslovsky, M. D.; Gernhardt, M. L.

    2017-01-01

    INTRODUCTION: The increase in the alveolar-arterial oxygen (O2) partial pressure gradient during increasing hypoxia may further increase in microgravity (microG). METHODS: Four male astronauts on STS-69 (1995) and 4 on STS-72 (1996) submitted to an acute sequential hypoxic challenge by breathing for 4 minutes at 18.0%, 14.9%, 13.5%, 12.9%, and 12.2% O2 - balance nitrogen at sea level. The 18.0% O2 mixture was equivalent to an inspired O2 partial pressure (PIO2) of 127 mm Hg when exposed to 527 mm Hg while breathing 26.5% O2 for several days in ?G. A Novametrix CO2SMO Model 7100 recorded heart rate (HR, beats × min-1) and hemoglobin (Hb) O2 saturation through finger pulse oximetry (SpO2, %), end-tidal carbon dioxide partial pressure (PETCO2, mm Hg), and respiration rate (RR, breaths/min) through an infrared capnograph positioned in a mouthpiece. Measurements were also taken the day of return to Earth (R+0) and at R+2. Linear mixed effects models assessed changes in SpO2 after exposure to ?microG. Interactions between measurement condition and available physiologic measurements were also explored. RESULTS: Astronaut SpO2 levels at baseline, R+0, and R+2 were not significantly different from in flight, about 97% given a PIO2 of 127 mm Hg. There was no difference in astronaut SpO2 levels between baseline and R+0 or R+2 over the hypoxic challenge. Additionally, no significant interactions were identified. CONCLUSIONS: While microG did not affect astronaut Hb O2 saturation in this study, large within- and between-subject variability in SpO2 at increasingly hypoxic doses require a deeper understanding of subject-specific factors that influence O2 transfer onto Hb.

  4. Development of Recombinant Hemoglobin-Based Oxygen Carriers

    PubMed Central

    Varnado, Cornelius L.; Mollan, Todd L.; Birukou, Ivan; Smith, Bryan J.Z.; Henderson, Douglas P.

    2013-01-01

    Abstract Significance: The worldwide blood shortage has generated a significant demand for alternatives to whole blood and packed red blood cells for use in transfusion therapy. One such alternative involves the use of acellular recombinant hemoglobin (Hb) as an oxygen carrier. Recent Advances: Large amounts of recombinant human Hb can be expressed and purified from transgenic Escherichia coli. The physiological suitability of this material can be enhanced using protein-engineering strategies to address specific efficacy and toxicity issues. Mutagenesis of Hb can (i) adjust dioxygen affinity over a 100-fold range, (ii) reduce nitric oxide (NO) scavenging over 30-fold without compromising dioxygen binding, (iii) slow the rate of autooxidation, (iv) slow the rate of hemin loss, (v) impede subunit dissociation, and (vi) diminish irreversible subunit denaturation. Recombinant Hb production is potentially unlimited and readily subjected to current good manufacturing practices, but may be restricted by cost. Acellular Hb-based O2 carriers have superior shelf-life compared to red blood cells, are universally compatible, and provide an alternative for patients for whom no other alternative blood products are available or acceptable. Critical Issues: Remaining objectives include increasing Hb stability, mitigating iron-catalyzed and iron-centered oxidative reactivity, lowering the rate of hemin loss, and lowering the costs of expression and purification. Although many mutations and chemical modifications have been proposed to address these issues, the precise ensemble of mutations has not yet been identified. Future Directions: Future studies are aimed at selecting various combinations of mutations that can reduce NO scavenging, autooxidation, oxidative degradation, and denaturation without compromising O2 delivery, and then investigating their suitability and safety in vivo. Antioxid. Redox Signal. 18, 2314–2328. PMID:23025383

  5. Expression and Purification of Recombinant Hemoglobin in Escherichia coli

    PubMed Central

    Natarajan, Chandrasekhar; Jiang, Xiaoben; Fago, Angela; Weber, Roy E.; Moriyama, Hideaki; Storz, Jay F.

    2011-01-01

    Background Recombinant DNA technologies have played a pivotal role in the elucidation of structure-function relationships in hemoglobin (Hb) and other globin proteins. Here we describe the development of a plasmid expression system to synthesize recombinant Hbs in Escherichia coli, and we describe a protocol for expressing Hbs with low intrinsic solubilities. Since the α- and β-chain Hbs of different species span a broad range of solubilities, experimental protocols that have been optimized for expressing recombinant human HbA may often prove unsuitable for the recombinant expression of wildtype and mutant Hbs of other species. Methodology/Principal Findings As a test case for our expression system, we produced recombinant Hbs of the deer mouse (Peromyscus maniculatus), a species that has been the subject of research on mechanisms of Hb adaptation to hypoxia. By experimentally assessing the combined effects of induction temperature, induction time and E. coli expression strain on the solubility of recombinant deer mouse Hbs, we identified combinations of expression conditions that greatly enhanced the yield of recombinant protein and which also increased the efficiency of post-translational modifications. Conclusion/Significance Our protocol should prove useful for the experimental study of recombinant Hbs in many non-human animals. One of the chief advantages of our protocol is that we can express soluble recombinant Hb without co-expressing molecular chaperones, and without the need for additional reconstitution or heme-incorporation steps. Moreover, our plasmid construct contains a combination of unique restriction sites that allows us to produce recombinant Hbs with different α- and β-chain subunit combinations by means of cassette mutagenesis. PMID:21625463

  6. Measuring and modeling hemoglobin aggregation below the freezing temperature.

    PubMed

    Rosa, Mónica; Lopes, Carlos; Melo, Eduardo P; Singh, Satish K; Geraldes, Vitor; Rodrigues, Miguel A

    2013-08-01

    Freezing of protein solutions is required for many applications such as storage, transport, or lyophilization; however, freezing has inherent risks for protein integrity. It is difficult to study protein stability below the freezing temperature because phase separation constrains solute concentration in solution. In this work, we developed an isochoric method to study protein aggregation in solutions at -5, -10, -15, and -20 °C. Lowering the temperature below the freezing point in a fixed volume prevents the aqueous solution from freezing, as pressure rises until equilibrium (P,T) is reached. Aggregation rates of bovine hemoglobin (BHb) increased at lower temperature (-20 °C) and higher BHb concentration. However, the addition of sucrose substantially decreased the aggregation rate and prevented aggregation when the concentration reached 300 g/L. The unfolding thermodynamics of BHb was studied using fluorescence, and the fraction of unfolded protein as a function of temperature was determined. A mathematical model was applied to describe BHb aggregation below the freezing temperature. This model was able to predict the aggregation curves for various storage temperatures and initial concentrations of BHb. The aggregation mechanism was revealed to be mediated by an unfolded state, followed by a fast growth of aggregates that readily precipitate. The aggregation kinetics increased for lower temperature because of the higher fraction of unfolded BHb closer to the cold denaturation temperature. Overall, the results obtained herein suggest that the isochoric method could provide a relatively simple approach to obtain fundamental thermodynamic information about the protein and the aggregation mechanism, thus providing a new approach to developing accelerated formulation studies below the freezing temperature.

  7. Hemoglobin Variability Does Not Predict Mortality in European Hemodialysis Patients

    PubMed Central

    Kim, Joseph; Kronenberg, Florian; Aljama, Pedro; Anker, Stefan D.; Canaud, Bernard; Molemans, Bart; Stenvinkel, Peter; Schernthaner, Guntram; Ireland, Elizabeth; Fouqueray, Bruno; Macdougall, Iain C.

    2010-01-01

    Patients with CKD exhibit significant within-patient hemoglobin (Hb) level variability, especially with the use of erythropoiesis stimulating agents (ESAs) and iron. Analyses of dialysis cohorts in the United States produced conflicting results regarding the association of Hb variability with patient outcomes. Here, we determined Hb variability in 5037 European hemodialysis (HD) patients treated over 2 years to identify predictors of high variability and to evaluate its association with all-cause and cardiovascular disease (CVD) mortality. We assessed Hb variability with various methods using SD, residual SD, time-in-target (11.0 to 12.5 g/dl), fluctuation across thresholds, and area under the curve (AUC). Hb variability was significantly greater among incident patients than prevalent patients. Compared with previously described cohorts in the United States, residual SD was similar but fluctuations above target were less frequent. Using logistic regression, age, body mass index, CVD history, dialysis vintage, serum albumin, Hb, angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) use, ESA use, dialysis access type, dialysis access change, and hospitalizations were significant predictors of high variability. Multivariable adjusted Cox regression showed that SD, residual SD, time-in-target, and AUC did not predict all-cause or CVD mortality during a median follow-up of 12.4 months (IQR: 7.7 to 17.4). However, patients with consistently low levels of Hb (<11 g/dl) and those who fluctuated between the target range and <11 g/dl had increased risks for death (RR 2.34; 95% CI: 1.24 to 4.41 and RR 1.74; 95% CI: 1.00 to 3.04, respectively). In conclusion, although Hb variability is common in European HD patients, it does not independently predict mortality. PMID:20798262

  8. Non-symbiotic hemoglobins in the life of seeds.

    PubMed

    Matilla, Angel J; Rodríguez-Gacio, María del Carmen

    2013-03-01

    Non-symbiotic hemoglobins (nsHbs), ancestors of symbiotic-Hbs, are hexacoordinated dimeric proteins, for which the crystal structure is well described. According to the extent of hexacoordination, nsHbs are classified as belonging to class-1 (nsHbs1) or class-2 (nsHbs2). The nsHbs1 show weak hexacoordination, moderate rates of O(2)-binding, very small rates of O(2) dissociation, and a remarkably high affinity for O(2), all suggesting a function involving O(2) scavenging. In contrast, the nsHbs2 exhibit strong hexacoordination, low rates of O(2)-binding and moderately low O(2) dissociation and affinity, suggesting a sensing role for sustained low (μM) levels of O(2). The existence of spatial and specific expression of nsHbs1 suggests that nsHbs play tissue-specific rather than housekeeping functions. The permeation of O(2) into seeds is usually prevented during the desiccation phase and early imbibition, generating an internal hypoxic environment that leads to ATP limitation. During evolution, the seed has acquired mechanisms to prevent or reduce this hypoxic stress. The nsHbs1/NO cycle appear to be involved in modulating the redox state in the seed and in maintaining an active metabolism. Under O(2) deficit, NADH and NO are synthesized in the seed and nsHbs1 scavenges O(2), which is used to transform NO into NO(3)(-) with concomitant formation of Fe(3+)-nsHbs1. Expression of nsHbs1 is not detectable in dry viable seeds. However, in the seeds cross-talk occurs between nsHbs1 and NO during germination. This review considers the current status of our knowledge of seed nsHbs and considers key issues of further work to better understand their role in seed physiology. PMID:23286879

  9. Distribution, adaptation and physiological meaning of thiols from vertebrate hemoglobins.

    PubMed

    Reischl, Evaldo; Dafre, Alcir Luiz; Franco, Jeferson Luis; Wilhelm Filho, Danilo

    2007-01-01

    In the present review, the sequences of hemoglobins (Hb) of 267 adult vertebrate species belonging to eight major vertebrate taxa are examined for the presence and location of cysteinyl residues in an attempt at correlation with their ecophysiology. Essentially, all vertebrates have surface cysteinyl residues in Hb molecules whereby their thiol groups may become highly reactive. Thiol-rich Hbs may display eight or more thiols per tetramer. In vertebrates so far examined, the cysteinyl residues occur in 44 different sequence positions in alpha chains and 41 positions in beta chains. Most of them are conservatively located and occur in only a few positions in Teleostei, Aves and Mammalia, whereas they are dispersed in Amphibia. The internal cysteinyl residue alpha104 is ubiquitous in vertebrates. Residue beta93 is highly conserved in reptiles, birds and mammals. The number of cysteine residues per tetramer with solvent access varies in vertebrates, mammalians and bony fish having the lowest number of external residues, whereas nearly all external cysteine residues in Aves and Lepidosauria are of the surface crevice type. In cartilaginous fish, amphibians, Crocodylidae and fresh water turtles, a substantial portion of the solvent accessible thiols are of the totally external type. Recent evidence shows that some Hb thiol groups are highly reactive and undergo extensive and reversible S-thiolation, and that they may be implicated in interorgan redox equilibrium processes. Participation of thiol groups in nitric oxide ((*)NO) metabolism has also been proved. The evidence argues for a new physiologically relevant role for Hb via involvement in free radical and antioxidant metabolism. PMID:17368111

  10. Functional and Spectroscopic Characterization of Chlamydomonas reinhardtii Truncated Hemoglobins.

    PubMed

    Ciaccio, Chiara; Ocaña-Calahorro, Francisco; Droghetti, Enrica; Tundo, Grazia R; Sanz-Luque, Emanuel; Polticelli, Fabio; Visca, Paolo; Smulevich, Giulietta; Ascenzi, Paolo; Coletta, Massimo

    2015-01-01

    The single-cell green alga Chlamydomonas reinhardtii harbors twelve truncated hemoglobins (Cr-TrHbs). Cr-TrHb1-1 and Cr-TrHb1-8 have been postulated to be parts of the nitrogen assimilation pathway, and of a NO-dependent signaling pathway, respectively. Here, spectroscopic and reactivity properties of Cr-TrHb1-1, Cr-TrHb1-2, and Cr-TrHb1-4, all belonging to clsss 1 (previously known as group N or group I), are reported. The ferric form of Cr-TrHb1-1, Cr-TrHb1-2, and Cr-TrHb1-4 displays a stable 6cLS heme-Fe atom, whereas the hexa-coordination of the ferrous derivative appears less strongly stabilized. Accordingly, kinetics of azide binding to ferric Cr-TrHb1-1, Cr-TrHb1-2, and Cr-TrHb1-4 are independent of the ligand concentration. Conversely, kinetics of CO or NO2- binding to ferrous Cr-TrHb1-1, Cr-TrHb1-2, and Cr-TrHb1-4 are ligand-dependent at low CO or NO2- concentrations, tending to level off at high ligand concentrations, suggesting the presence of a rate-limiting step. In agreement with the different heme-Fe environments, the pH-dependent kinetics for CO and NO2-binding to ferrous Cr-TrHb1-1, Cr-TrHb1-2, and Cr-TrHb1-4 are characterized by different ligand-linked protonation events. This raises the question of whether the simultaneous presence in C. reinhardtii of multiple TrHb1s may be related to different regulatory roles. PMID:25993270

  11. Human bulbar conjunctival hemodynamics in hemoglobin SS and SC disease

    PubMed Central

    Wanek, Justin; Gaynes, Bruce; Lim, Jennifer I.; Molokie, Robert; Shahidi, Mahnaz

    2014-01-01

    The known biophysical variations of hemoglobin (Hb) S and Hb C may result in hemodynamic differences between subjects with SS and SC disease. The purpose of this study was to measure and compare conjunctival hemodynamics between subjects with Hb SS and SC hemoglobinopathies. Image sequences of the conjunctival microcirculation were acquired in 9 healthy control subjects (Hb AA), 24 subjects with SC disease, and 18 subjects with SS disease, using a prototype imaging system. Diameter (D) and blood velocity (V) measurements were obtained in multiple venules of each subject. Data were categorized according to venule caliber by averaging V and D for venules with diameters less than (vessel size 1) or greater than (vessel size 2) 15 µm. V in vessel size 2 was significantly greater than V in vessel size 1 in the AA and SS groups (P ≥ 0.009), but not in the SC group (P = 0.1). V was significantly lower in the SC group as compared to the SS group (P = 0.03). In AA and SS groups, V correlated with D (P ≥ 0.005), but the correlation was not statistically significant in the SC group (P = 0.08). V was inversely correlated with hematocrit in the SS group for large vessels (P = 0.03); however, no significant correlation was found in the SC group (P ≥ 0.2). Quantitative assessment of conjunctival microvascular hemodynamics in SS and SC disease may advance understanding of sickle cell disease pathophysiology and thereby improve therapeutic interventions. PMID:23657867

  12. Channel catfish hemoglobin genes: identification, phylogenetic and syntenic analysis, and specific induction in response to heat stress.

    PubMed

    Feng, Jianbin; Liu, Shikai; Wang, Xiuli; Wang, Ruijia; Zhang, Jiaren; Jiang, Yanliang; Li, Chao; Kaltenboeck, Ludmilla; Li, Jiale; Liu, Zhanjiang

    2014-03-01

    Hemoglobins transport oxygen from gill to inner organs in fish, and this process is affected by temperature, one of the major environmental factors for fish. The hemoglobin gene clusters have been well studied in humans and several model fish species, but remain largely unknown in catfish. Here, eight α- and six β-hemoglobin genes were identified and characterized in channel catfish. Genomic synteny analysis showed that these hemoglobin genes were separated into two unlinked clusters, the MN cluster containing six α- and six β-hemoglobin genes, and the LA cluster consisting of two α-hemoglobin genes. Channel catfish hemoglobin genes were ubiquitously expressed in all the 10 tested tissues from healthy fish, but exhibited higher expression level in spleen, head kidney, and trunk kidney. In response to heat stress, hemoglobin genes, especially MN Hbα4, MN Hbα5, MN Hbα6, MN Hbβ4, MN Hbβ5, MN Hbβ6, LA Hbα1, and LA Hbα2, presumably the embryonic hemoglobin genes, were drastically up-regulated in the gill and head kidney of heat-tolerant fishes, but not in these tissues of the heat-intolerant fish, suggesting the importance of the embryonic hemoglobin genes in coping with the low oxygen conditions under heat stress.

  13. Structural characterization of hemoglobins from Monilifera and Frenulata tubeworms (Siboglinids): first discovery of giant hexagonal-bilayer hemoglobin in the former "Pogonophora" group.

    PubMed

    Meunier, Cédric; Andersen, Ann C; Bruneaux, Matthieu; Le Guen, Dominique; Terrier, Peran; Leize-Wagner, Emmanuelle; Zal, Franck

    2010-01-01

    Siboglinids are symbiotic polychete annelids having hemoglobins as essential oxygen- and sulfide-carriers for their endosymbiotic bacteria. We analyzed the structure of the hemoglobins from two species of siboglinids: the monilifera Sclerolinum contortum and the frenulata Oligobrachia webbi (i.e. haakonmosbiensis) from Norwegian cold seeps. Measured by Multi-Angle Laser Light Scattering (MALLS), Sclerolinum shows a 3190+/-50 kDa hexagonal bilayer hemoglobin (HBL-Hb) and a 461+/-46 kDa ring-Hb, just as vestimentifera, whereas Oligobrachia has a 409+/-3.7 kDa ring-Hb only. Electrospray Ionization-Mass Spectrometry (ESI-MS) showed Sclerolinum HBL-Hb composed of seven monomeric globins (15-16 kDa), three disulfide-bonded globin heterodimers and three linkers. The heterodimers always contain globin-b (15814.4+/-1.5 Da). Sclerolinum ring-Hb is composed of globins and dimers with identical masses as its HBL-Hb, but lacks linkers. Oligobrachia ring-Hb has three globin monomers (14-15 kDa) only, with no disulfide-bonded dimers. Comparison of Sclerolinum hemoglobins between Storegga and Haakon Mosby Mud Volcano, using the normalized height of deconvoluted ESI-MS peaks, shows differences in globin monomers abundances that could reflect genetic differences or differential gene expression between distinct seep populations. The discovery of HBL-Hb in Sclerolinum is a new element supporting the hypothesis of monilifera being phylogenetically more closely related to vestimentifera, than to frenulata.

  14. Hematologic and hemorheological determinants of resting and exercise-induced hemoglobin oxygen desaturation in children with sickle cell disease

    PubMed Central

    Waltz, Xavier; Romana, Marc; Lalanne-Mistrih, Marie-Laure; Machado, Roberto F.; Lamarre, Yann; Tarer, Vanessa; Hardy-Dessources, Marie-Dominique; Tressières, Benoît; Divialle-Doumdo, Lydia; Petras, Marie; Maillard, Frederic; Etienne-Julan, Maryse; Connes, Philippe

    2013-01-01

    The aim of the study was to determine the factors associated with resting and exercise-induced hemoglobin oxygen desaturation. The well-established six-minute walk test was conducted in 107 sickle cell children (50 with sickle hemoglobin C disease and 57 with sickle cell anemia) at steady state. Hemoglobin oxygen saturation was measured before and immediately after the six-minute walk test. Blood samples were obtained on the same day to measure hematologic and hemorheological parameters. Exercise-induced hemoglobin oxygen desaturation was defined as a drop in hemoglobin oxygen saturation of 3% or more at the end of the six-minute walk test compared to resting levels. No children with sickle hemoglobin C disease, but approximately 50% of children with sickle cell anemia showed mild or moderate oxygen desaturation at rest, which was independently associated with the percentage of reticulocytes. Exercise-induced hemoglobin oxygen desaturation was observed in 18% of children with sickle hemoglobin C disease and 34% of children with sickle cell anemia, and was independently associated with the six-minute walk test, acute chest syndrome rate and the strength of red blood cell aggregates in children with sickle cell anemia. No association was found in children with sickle hemoglobin C disease between exercise-induced hemoglobin oxygen desaturation and the measured parameters. Hemoglobin oxygen desaturation at rest was common in children with sickle cell anemia but not in children with sickle hemoglobin C disease, and was mainly associated with greater hemolysis. Physiological strain during exercise and red blood cell aggregation properties may predict the occurrence of exercise-induced hemoglobin oxygen desaturation in children with sickle cell anemia. PMID:23539539

  15. Altered sulfhydryl reactivity of hemoglobins and red blood cell membranes in congenital heinz body hemolytic anemia

    PubMed Central

    Jacob, Harry S.; Brain, Michael C.; Dacie, John V.

    1968-01-01

    The mechanisms of hemoglobin precipitation into Heinz bodies and hemolytic anemia that characterize congenital Heinz body hemolytic anemia (CHBHA) were studied in patients with the unstable hemoglobins, Köln (β-98 valine → methionine) and Hammersmith (β-42 phenylalanine → serine). The cysteines in the 93rd position of the β-chains of CHBHA hemoglobins bound glutathione excessively in mixed disulfide linkage. The resulting diminished “free” GSH within the cell accelerated hexose monophosphate shunt metabolism. The unique precipitability of CHBHA hemoglobins when heated at 50°C could be induced in normal hemoglobin A by artificially blockading its sulfhydryl groups with paramercuribenzoate (PMB). Reflecting the previously reported excessive flux of hemes from hemoglobin Köln, the expected heme/globin ratio in this hemoglobin was reduced by 30%. The further increment in heme loss that occurs with heat (50°C) underlies the unique heat precipitability of CHBHA hemoglobins; it was retarded if detachment of heme was inhibited by cyanide or carbon monoxide. Heinz bodies were attached to red cell membrane thiol groups presumably through mixed disulfide bonds, being released by mercaptoethanol. Binding of hemoglobin Köln-59Fe to red cell ghosts, which was markedly enhanced when Heinz bodies were generated at 50°C, was inhibited if membrane thiols were preblockaded by PMB. The depletion of membrane thiols by their reaction with Heinz bodies rendered CHBHA red cells hypersusceptible to membrane sulfhydryl inhibitors, as manifested by inordinate cation leakage, osmotic fragility, and autohemolysis. We conclude that both cellular and membrane thiols bind β-93 sulfhydryls of CHBHA hemoglobins as mixed disulfides. Concomitantly, heme avidity to β-92 lessens, suggesting that degradation of the resulting excessively freed heme may produce the pigmented dipyrroluria of this syndrome. Heinz bodies, reflecting the heightend precipitability of heme-deficient globin

  16. Maternal hemoglobin level and fetal outcome at low and high altitudes

    PubMed Central

    Steenland, Kyle; Tapia, Vilma

    2009-01-01

    Both, low (<7 g/dl) and high (>14.5 g/dl), maternal hemoglobin (Hb) levels have been related to poor fetal outcome. Most studies have been done at low altitude (LA). Here, we have sought to determine whether this relationship exists at both high and low altitude, and also whether there is an adverse effect of high altitude (HA) on fetal outcome independent of level of maternal hemoglobin. The study is based on a retrospective multicenter analysis of 35,449 pregnancies at LA and six other cities above 3000 meters. In analyses of all women at both LA and HA, those with Hb <9 g/dl had odds ratios (ORs) and 95% confidence intervals (CI) of 4.4 (CI: 2.8–6.7), 2.5 (CI: 1.9–3.2), and 1.4 (CI: 1.1–1.9) for stillbirths, preterm, and small for gestational age (SGA) births, respectively, compared with women with 11–12.9 g/dl of Hb, after adjustment for confounders. These risks by hemoglobin level differed little between women at LA and HA, suggesting that no correction of the definition of anemia is necessary for women at HA. Women living at high altitude with hemoglobin >15.5 g/dl had higher risks for stillbirths (OR: 1.3; CI: 1.05–1.3), preterm (OR: 1.5; CI 1.3–1.8), and SGA births (OR: 2.1, CI 1.8–2.3). There was also a significant adverse effect of living at HA, independent of hemoglobin level for all three outcomes (OR: 3.9, 1.7, and 2.3; CI: 2.8–5.2, 1.5–1.9, and 2.1–2.5) for stillbirths, preterms, and SGA respectively, after adjusting for hemoglobin level. Both, high and low maternal hemoglobin levels were related to poor pregnancy outcome, with similar effect of low hemoglobin in both LA and HA. Our data suggest, that maternal hemoglobin above 11 g/dl but below 13 g/dl is the area of minimal risk of poor adverse outcomes. Living at HA had an adverse effect independent of hemoglobin level. PMID:19741055

  17. Development of severe anemia during fever episodes in patients with hemoglobin E trait and hemoglobin H disease combinations.

    PubMed

    Jetsrisuparb, Arunee; Sanchaisuriya, Kanokwan; Fucharoen, Goonnapa; Fucharoen, Supan; Wiangnon, Surapon; Jetsrisuparb, Charoon; Sirijirachai, Jittima; Chansoong, Kanchana

    2006-04-01

    Globin chain imbalance and tissue hypoxia are important determinants of the clinical severity of thalassemias. Phenotypic expression may be further modified by interactions between alpha- and beta-thalassemia defects. We retrospectively and prospectively studied the clinical and hematologic features in children and adults with hemoglobin (Hb) E trait/Hb H disease (SEA/Paksé) (seven cases) and Hb E trait/Hb H disease (SEA/Constant Spring) (29 cases) and found that they had similar presentations. The severity of these two intermediate thalassemic manifestations ranged from very mild to severe. Severe anemia developed in accordance with very high fever, whereupon the range of Hb and hematocrit (Hct) levels declined to 5.2-5.8 g/dL and 13%-19%, respectively. In one case, during a hemoconcentrated state as occurs in dengue hemorrhagic fever, the Hb and Hct were 10 g/dL and 31%; the latter rose to 35% after fluid therapy. In some patients, the range of Hb and Hct levels was constantly low (4.3-5.8 g/dL and 15%-19%, respectively). (If dengue hemorrhagic fever is misdiagnosed, a fatal outcome may occur for thalassemic patients.) After a hemodiluted condition as in acute post-streptococcal glomerulonephritis, the respective Hb and Hct were 5.4 g/dL and 19%. These observations suggest that the instability of Hb E, especially during fever, may play an important role in the clinical manifestations of Hb E trait/Hb H disease with Hb Paksé and with Hb Constant Spring.

  18. Pharmacokinetic study of enclosed hemoglobin and outer lipid component after the administration of hemoglobin vesicles as an artificial oxygen carrier.

    PubMed

    Taguchi, Kazuaki; Urata, Yukino; Anraku, Makoto; Maruyama, Toru; Watanabe, Hiroshi; Sakai, Hiromi; Horinouchi, Hirohisa; Kobayashi, Koichi; Tsuchida, Eishun; Kai, Toshiya; Otagiri, Masaki

    2009-07-01

    The hemoglobin vesicle (HbV) is an artificial oxygen carrier that encapsulates a concentrated Hb solution in lipid vesicles (liposomes). The pharmacokinetic properties of HbV were investigated in mice and rats. With use of HbV in which the internal Hb was labeled with (125)I ((125)I-HbV) and cell-free (125)I-Hb, it was found that encapsulation of Hb increased the half-life by 30 times, accompanied by decreased distribution in both the liver and kidney. The half-life of HbV was increased, and the uptake clearance for the liver and spleen were decreased with increasing doses of HbV. In an in vitro study, the specific uptake and degradation of HbV in RAW 264.7 cells were found, but this was not the case for parenchymal and endothelial cells. The pharmacokinetics of HbV components (internal Hb and liposomal lipid) were also investigated using (125)I-HbV and (3)H-HbV (liposomal cholesterol was radiolabeled with tritium-3). The time courses for the plasma concentration curves of (125)I-HbV, (3)H-HbV, and iron derived from HbV suggest that HbV maintain an intact structure in the blood circulation up to 24 h after injection. (125)I-HbV and (3)H-HbV were distributed mainly to the liver and spleen. Internal Hb disappeared from both the liver and spleen 5 days after injection, and the liposomal cholesterol disappeared at approximately 14 days. Internal Hb was excreted into the urine and cholesterol into feces via biliary excretion. These results suggest that the HbV has a reasonable blood retention and metabolic and excretion performance and could be used as an oxygen carrier.

  19. Quantitative, single-step dual measurement of hemoglobin A1c and total hemoglobin in human whole blood using a gold sandwich immunochromatographic assay for personalized medicine.

    PubMed

    Ang, Shu Hwang; Rambeli, Musalman; Thevarajah, T Malathi; Alias, Yatimah Binti; Khor, Sook Mei

    2016-04-15

    We describe a gold nanoparticle-based sandwich immunoassay for the dual detection and measurement of hemoglobin A1c (HbA1c) and total hemoglobin in the whole blood (without pretreatment) in a single step for personalized medicine. The optimized antibody-functionalized gold nanoparticles immunoreact simultaneously with HbA1c and total hemoglobin to form a sandwich at distinctive test lines to transduce visible signals. The applicability of this method as a personal management tool was demonstrated by establishing a calibration curve to relate % HbA1c, a useful value for type 2 diabetes management, to the signal ratio of captured HbA1c to all other forms of hemoglobin. The platform showed excellent selectivity (100%) toward HbA1c at distinctive test lines when challenged with HbA0, glycated HbA0 and HbA2. The reproducibility of the measurement was good (6.02%) owing to the dual measurement of HbA1c and total hemoglobin. A blood sample stability test revealed that the quantitative measurement of % HbA1c was consistent and no false-positive results were detected. Also, this method distinguished the blood sample with elevated HbF from the normal samples and the variants. The findings of this study highlight the potential of a lateral flow immunosensor as a simple, inexpensive, consistent, and convenient strategy for the dual measurement of HbA1c and total Hb to provide useful % HbA1c values for better on-site diabetes care.

  20. Thermodynamic aspects of the linkage between binding of chloride and oxygen to human hemoglobin

    PubMed Central

    Haire, Robert N.; Hedlund, Bo E.

    1977-01-01

    Oxygen isotherms of human hemoglobin measured in distilled water and in solutions of sodium chloride in the concentration range from 0.02 to 3.0 M indicate that the oxygen affinity decreases up to about 1 M salt and then begins to increase. The isotherms obtained in the range from 0.02 to 0.6 M sodium chloride, at 37° and pH 7.4, have been analyzed in terms of changes in Gibbs free energy of heme ligation, resulting from the differential interaction between the chloride ion and the two forms of hemoglobin. The maximal theoretical change in Gibbs free energy that chloride ion can exert on the oxygen binding of hemoglobin amounts to 4.9 ± 0.2 kcal/mol (21 ± 0.8 kJ/mol) of hemoglobin tetramer. A plot of the logarithm of oxygen concentration at half saturation versus the logarithm of the chloride concentration has a slope of 0.40, suggesting 1.6 apparent chloride sites per hemoglobin tetramer. Because the interaction between chloride and hemoglobin is dependent on pH, the apparent thermodynamic linkage between chloride and oxygen binding will also include the salt dependence of the Bohr effect at pH 7.4. The fractional change in Gibbs free energy, measured as a function of the chloride concentration, can be approximated by the binding isotherm between a protein and a ligand, using an association constant of 11 M-1. Thus, if the number of oxygen-linked chloride sites is more than one per hemoglobin tetramer, these sites must be considered independent. PMID:270660

  1. Capacity of reductants and chelators to prevent lipid oxidation catalyzed by fish hemoglobin.

    PubMed

    Maestre, Rodrigo; Pazos, Manuel; Iglesias, Jacobo; Medina, Isabel

    2009-10-14

    The efficiency of different reductants (reduced glutathione, ascorbic acid, and catalase) and metal chelators [ethylenediaminetetraacetic acid (EDTA), citric acid, sodium tripolyphosphate (STPP), and adenosine-5'-triphosphate (ATP)] to inhibit lipid oxidation promoted by fish hemoglobin was investigated. The inhibitory activity on hemoglobin-catalyzed lipid oxidation was also evaluated for grape oligomeric catechins (proanthocyanidins), which have both reducing and chelating properties. The antioxidant activity was studied in two different lipid oxidation models, liposomes and washed minced fish muscle. Grape proanthocyanidins were found to be significantly more effective than other reductants to prevent hemoglobin-mediated lipid oxidation in both liposomes and washed fish muscle. Reduced glutathione was also efficient to retard lipid oxidation at the same molarity in washed fish muscle, whereas catalase and ascorbic acid showed a lower antioxidant activity. Metal chelators were less active than reductants, and consequently, the former were necessarily evaluated at much higher concentration than grape proanthocyanidins and reducing compounds. STPP was found to be the iron chelator with the strongest efficiency to delay hemoglobin-mediated lipid oxidation followed by EDTA. Citric acid and ATP were ineffective in retarding lipid oxidation in both systems. Grape proanthocyanidins provided the most extensive protection to preserve hemoglobin at ferrous state in washed fish muscle. Our results draw attention to the greater capacity of reducing compounds to prevent fish hemoglobin-mediated lipid oxidation in comparison with iron chelators, suggesting that the free radical scavenging and/or reduction of ferrylHb species are crucial actions to avoid the pro-oxidant capacity of fish hemoglobin.

  2. Extraction of Phospholipids from Human Erythrocyte Membranes by Hemoglobin Oxidation Products.

    PubMed

    Brunauer, Linda S; Chen, James Y; Koontz, M Zachary; Davis, Kathryn K; O'Brien, Laura E; Wright, Emily M; Huestis, Wray H

    2016-06-01

    This investigation examines oxidation conditions under which hemoglobin extracts membrane phospholipid from erythrocytes and model membranes. In erythrocytes made echinocytic with exogenous phospholipid, addition of hemoglobin oxidized with hydrogen peroxide (H2O2) or Vitamin C (conditions that result in the formation of significant quantities of choleglobin), but not ferricyanide (which produces predominantly methemoglobin), induced dose-dependent shape reversion to less echinocytic forms, consistent with extraction of phospholipids from the exofacial side of the membrane. Erythrocytes preloaded with radiolabeled phosphatidylcholine or NBD-labeled phosphatidylcholine, phosphatidylglycerol or phosphatidic acid, exhibited greatest extraction of radiolabel or fluorescence signal with exogenous hemoglobin oxidized via H2O2 or Vitamin C, but not ferricyanide. However, with NBD-phosphatidylserine (a preferential inner monolayer intercalator), significantly less extraction of labeled lipid occurred with oxidized hemoglobin prepared under all three oxidizing conditions. In dimyristoylphosphatidylcholine liposomes containing radiolabeled phosphatidylcholine, phosphatidylserine or phosphatidylethanolamine, subsequent addition of hemoglobin oxidized with H2O2 or Vitamin C extracted radiolabeled lipid with significantly greater efficiency than ferricyanide-treated hemoglobin, with enhanced extraction detectable at levels approaching physiological plasma oxidant concentrations. Radiolabeled lipid extraction was comparable for phospholipids containing saturated acyl chains between 12 and 18 carbons but diminished significantly for oleoyl-containing phospholipids. Hemoglobin dimerization occurred at very low levels with H2O2 treatment, and even lower levels with Vitamin C treatment, and thus did not correlate to the high efficiency and consistent levels of lipid extraction observed with these treatments. These findings indicate that choleglobin extracts lipids from cell

  3. Ex vivo hemoglobin status study using photoacoustic computed tomography small animal scanner

    NASA Astrophysics Data System (ADS)

    Liu, Bo; Kruger, Robert; Reinecke, Daniel; Stantz, Keith M.

    2010-02-01

    Purpose: The purpose of this study is to calibrate the PCT scanner to quantify the hemoglobin status utilizing a blood flow phantom. Materials and Methods: A blood circulation system was designed and constructed to control the oxygen saturation and hemoglobin concentration of blood. As a part of the circulation system, a 1.1mm FEP tube was placed in the center of imaging tank of PCT scanner as the imaging object. Photoacoustic spectra (690-950 nm) was acquired for different hemoglobin concentrations (CtHb) and oxygen saturation levels (SaO2), where the formers was formed by diluting blood samples with PBS and the latter by mixing blood with gases at different oxygen content. Monte Carlo simulations were performed to calculate the photon energy depositions in the phantom tube, which took into account photon losses in water and blood. A Kappa value which represents the energy transfer efficiency of hemoglobin molecule was calculated based on the PCT measurement and simulation result. The final SaO2 value of each blood sample was calculated based on the PCT spectrum and Kappa value. These oxygen saturation results were compared with co-oximeter measurements to obtain systematic errors. Results and Conclusion: The statistic error of calculating Kappa value from hemoglobin concentration experiment was less than 5%. The systematic error between PCT spectra analysis and co-oximeter analysis for hemoglobin oxygen saturation was -4.5%. These calibration techniques used to calculate Kappa and hemoglobin absorption spectra would be used in hypoxia measurements in tumors as well as for endogenous biomarkers studies.

  4. Kinetics of the polymerization of hemoglobin in high and low phosphate buffers.

    PubMed

    Adachi, K; Asakura, T

    1982-01-01

    Diluted solutions of deoxyhemoglobin S in concentrated phosphate buffer form aggregates or gels with a clear exhibition of a delay time. The aggregates can be liquified by cooling, bubbling with O2 or CO gas, or the dilution of phosphate buffer with water. These properties can be used as a simple method for studying the mechanism of polymerization and depolymerization of hemoglobins. The advantages of this method are: 1) The amount of hemoglobin sample required is only 1% to 5% of that required for the gelation of deoxy-Hb S in low phosphate buffer. 2) The kinetics can be measured turbidimetrically using an ordinary spectrophotometer. 3) The solubility of hemoglobin can be directly determined by taking the absorption spectrum of the supernatant solution after polymerization. 4) The polymer phase can be easily separated from the solution so that the amount and composition of the polymers can be analyzed. 5) The volume of the polymer phase is so small that excluded volume effect can be neglected. 6) The method can be applied to the study of polymerization of non-sickle hemoglobins and that of mixtures of sickle and non-sickle hemoglobins. The major question is whether the polymerization of hemoglobin in concentrated phosphate buffer is the same as that of deoxy-Hb S in low phosphate buffer. To answer this question, we studied the polymerization of Hb S, Hb A, Hb C Harlem, and Hb C in phosphate buffers of different molarities. We also studied the mechanism of the conversion of gels of these hemoglobins into crystals.

  5. [Research on Early Diagnosis of Gastric Cancer by the Surface Enhanced Raman Spectroscopy of Human Hemoglobin].

    PubMed

    Wang, Wei; Pan, Zhi-feng; Tang, Wei-yue; Li, Yun-tao; Fan, Chun-zhen

    2015-12-01

    Early diagnosis have great positive effect on the treatment of gastric cancer patients. Raman spectroscopy can provide a useful monitor for hemoglobin dynamics. Besides, Raman spectroscopy has notable advantages in the fields of abnormal hemoglobin diagnosis, hemoglobin oxygen saturation deter mination and blood methemoglobin analysis. In this paper, novel silver colloid was synthesized by microwave heated method. The surface enhanced Raman spectrums of hemoglobin from 11 normal persons and 20 gastric cancer patients are measured and analyzed in order to obtain spectrums which are high repeatability and characteristic peaks protruding. By analyzing the assignations of the SERS bands, it found that the content of asparagine, tyrosine and phenylalanine in the hemoglobin are significantly lower than healthy people. Discussing the structure of hemoglobin, when hemoglobin combines with oxygen, Fe²⁺ is in a low spin state, ionic radius shrinks and moves 0. 075 nm and fall into the pore in the middle of the heme porphyrin ring plane. This spatial variation affects F8His connected with the iron, will narrow the gap between the globin in the two strands of the helix, as a result, HC2 tyrosine pushed out of the void. Using this mechanism, the absorption peak of 1 560 cm⁻¹ confirmed that the tyrosine content in patients with gastric cancer was lower than that of normal people. Principal component analysis(PCA) is employed to get a three-dimensional scatter plot of PC scores for the health and cancer groups, and it can be learned that they are distributed in separate areas. By using the method of discriminate analysis, it is found that the diagnostic algorithm separates the two groups with sensitivity of 90.0% and diagnostic specificity of 90.9%, the overall diagnostic accuracy was 90.3%. The results from this exploratory study demonstrate that, SERS detection of oxyhemoglobin combined with multivariate analysis would be an effective method for early diagnosis of gastric

  6. Capacity of reductants and chelators to prevent lipid oxidation catalyzed by fish hemoglobin.

    PubMed

    Maestre, Rodrigo; Pazos, Manuel; Iglesias, Jacobo; Medina, Isabel

    2009-10-14

    The efficiency of different reductants (reduced glutathione, ascorbic acid, and catalase) and metal chelators [ethylenediaminetetraacetic acid (EDTA), citric acid, sodium tripolyphosphate (STPP), and adenosine-5'-triphosphate (ATP)] to inhibit lipid oxidation promoted by fish hemoglobin was investigated. The inhibitory activity on hemoglobin-catalyzed lipid oxidation was also evaluated for grape oligomeric catechins (proanthocyanidins), which have both reducing and chelating properties. The antioxidant activity was studied in two different lipid oxidation models, liposomes and washed minced fish muscle. Grape proanthocyanidins were found to be significantly more effective than other reductants to prevent hemoglobin-mediated lipid oxidation in both liposomes and washed fish muscle. Reduced glutathione was also efficient to retard lipid oxidation at the same molarity in washed fish muscle, whereas catalase and ascorbic acid showed a lower antioxidant activity. Metal chelators were less active than reductants, and consequently, the former were necessarily evaluated at much higher concentration than grape proanthocyanidins and reducing compounds. STPP was found to be the iron chelator with the strongest efficiency to delay hemoglobin-mediated lipid oxidation followed by EDTA. Citric acid and ATP were ineffective in retarding lipid oxidation in both systems. Grape proanthocyanidins provided the most extensive protection to preserve hemoglobin at ferrous state in washed fish muscle. Our results draw attention to the greater capacity of reducing compounds to prevent fish hemoglobin-mediated lipid oxidation in comparison with iron chelators, suggesting that the free radical scavenging and/or reduction of ferrylHb species are crucial actions to avoid the pro-oxidant capacity of fish hemoglobin. PMID:19736927

  7. [Research on Early Diagnosis of Gastric Cancer by the Surface Enhanced Raman Spectroscopy of Human Hemoglobin].

    PubMed

    Wang, Wei; Pan, Zhi-feng; Tang, Wei-yue; Li, Yun-tao; Fan, Chun-zhen

    2015-12-01

    Early diagnosis have great positive effect on the treatment of gastric cancer patients. Raman spectroscopy can provide a useful monitor for hemoglobin dynamics. Besides, Raman spectroscopy has notable advantages in the fields of abnormal hemoglobin diagnosis, hemoglobin oxygen saturation deter mination and blood methemoglobin analysis. In this paper, novel silver colloid was synthesized by microwave heated method. The surface enhanced Raman spectrums of hemoglobin from 11 normal persons and 20 gastric cancer patients are measured and analyzed in order to obtain spectrums which are high repeatability and characteristic peaks protruding. By analyzing the assignations of the SERS bands, it found that the content of asparagine, tyrosine and phenylalanine in the hemoglobin are significantly lower than healthy people. Discussing the structure of hemoglobin, when hemoglobin combines with oxygen, Fe²⁺ is in a low spin state, ionic radius shrinks and moves 0. 075 nm and fall into the pore in the middle of the heme porphyrin ring plane. This spatial variation affects F8His connected with the iron, will narrow the gap between the globin in the two strands of the helix, as a result, HC2 tyrosine pushed out of the void. Using this mechanism, the absorption peak of 1 560 cm⁻¹ confirmed that the tyrosine content in patients with gastric cancer was lower than that of normal people. Principal component analysis(PCA) is employed to get a three-dimensional scatter plot of PC scores for the health and cancer groups, and it can be learned that they are distributed in separate areas. By using the method of discriminate analysis, it is found that the diagnostic algorithm separates the two groups with sensitivity of 90.0% and diagnostic specificity of 90.9%, the overall diagnostic accuracy was 90.3%. The results from this exploratory study demonstrate that, SERS detection of oxyhemoglobin combined with multivariate analysis would be an effective method for early diagnosis of gastric

  8. Maternal Hemoglobin Levels during Pregnancy and their Association with Birth Weight of Neonates

    PubMed Central

    Moghaddam Tabrizi, F; Barjasteh, S

    2015-01-01

    Back ground Anemia in pregnancy is associated with increased rates of maternal and perinatal mortality, premature delivery, low birth weight, and other adverse outcomes Materials and Methods A prospective study was conducted on 1405 Iranian pregnant women who delivered during 2015. Blood was collected from all the subjects to measure the hemoglobin (Hb) during 16-19 weeks, 22-24 weeks, and 34-36 weeks of gestation. According to the level of hemoglobin, it is divided into 4 groups. Group 1; Hb > 10.1 gm/100ml (control group), Group 2; Hb= 8.1-10 gm/100ml (mild anemia) Group 3; Hb= 6.5-8 gm/100ml (moderate anemia) Group 4; Hb <6.5 gm/100ml (severe anemia). After delivery, the neonates were weighted within 24 hours after birth. Maternal hemoglobin and birth weights were compared. Results The anemia prevalence was 20.2% (Hb<10g/dl). Out of them, 16.2 % hadmoderate anemia (Hb=6.5-8 g/dl) and 83.8% had mild anemia (Hb=8.1-10 g/dl). Severe anemia did not detect in pregnant women. The hemoglobin levels in non anemic group showed a drop in the second trimester. Pregnant women with hemoglobin less than 10 g/dl, considered as anemic gave birth to neonates with birth weight of 2.6kg, while pregnant women with higher hemoglobin level (>10 g/dl), considered as normal gave birth to heavier and normal babies (3.3 kg). The severity of anemia during three trimesters was closely associated with birth weight of newborns. Conclusion The low hemoglobin values during three trimesters of pregnancy were associated with low birth weight in Iran. The anemia can lead to intra uterine growth retardation. PMID:26985354

  9. Reaction of dehydropyrrolizidine alkaloids with valine and hemoglobin.

    PubMed

    Zhao, Yuewei; Wang, Shuguang; Xia, Qingsu; Gamboa da Costa, Gonçalo; Doerge, Daniel R; Cai, Lining; Fu, Peter P

    2014-10-20

    Pyrrolizidine alkaloid-containing plants are probably the most common poisonous plants affecting livestock, wildlife, and humans. Pyrrolizidine alkaloids exert toxicity through metabolism to dehydropyrrolizidine alkaloids that bind to cellular protein and DNA, leading to hepatotoxicity, genotoxicity, and tumorigenicity. To date, it is not clear how dehydropyrrolizidine alkaloids bind to cellular constituents, including amino acids and proteins, resulting in toxicity. Metabolism of carcinogenic monocrotaline, riddelliine, and heliotrine produces dehydromonocrotaline, dehyroriddelliine, and dehydroheliotrine, respectively, as primary reactive metabolites. In this study, we report that reaction of dehydromonocrotaline with valine generated four highly unstable 6,7-dihydro-7-hydroxy-1-hydroxymethyl-5H-pyrrolizine (DHP)-derived valine (DHP-valine) adducts. For structural elucidation, DHP-valine adducts were derivatized with phenyl isothiocyanate (PITC) to DHP-valine-PITC products. After HPLC separation, their structures were characterized by mass spectrometry, UV-visible spectrophotometry, (1)H NMR, and (1)H-(1)H COSY NMR spectral analysis. Two DHP-valine-PITC adducts, designated as DHP-valine-PITC-1 and DHP-valine-PITC-3, had the amino group of valine linked to the C7 position of the necine base, and the other two DHP-valine-PITC products, DHP-valine-PITC-2 and DHP-valine-PITC-4, linked to the C9 position of the necine base. DHP-valine-PITC-1 was interconvertible with DHP-valine-PITC-3, and DHP-valine-PITC-2 was interconvertible with DHP-valine-PITC-4. Reaction of dehydroriddelliine and dehydroheliotrine with valine provided similar results. However, reaction of valine and dehydroretronecine (DHR) under similar experimental conditions did not produce DHP-valine adducts. Reaction of dehydromonocrotaline with rat hemoglobin followed by derivatization with PITC also generated the same four DHP-valine-PITC adducts. This represents the first full structural elucidation of

  10. Hemoglobin and Ferritin Concentrations in Subjects with Metabolic Syndrome

    PubMed Central

    Adediran, Adewumi; Uche, Ebele; Akinbami, Akinsegun; Dada, Akin; Wakama, Tamunomieibi; Damulak, Dapus; Ajibola, Sarah; Okwegbuna, Oluwakemi

    2015-01-01

    BACKGROUND Metabolic syndrome (MetS), a clinical condition characterized by insulin resistance, glucose intolerance, dyslipidemia, hypertension, and obesity, has been linked with raised levels of serum ferritin (Sfr) concentrations. OBJECTIVES This study was carried out to compare hemoglobin (Hb) and Sfr concentrations in patients with MetS, regular donors and first-time donors. MATERIALS AND METHODS A total of 102 subjects who were between 18 and 60 years were enrolled for the study. They were divided into three groups. The first group (n = 20) was made up of 5 males and 15 females, all who met the criteria that define MetS. The second group (n = 52; M = 34, F = 18) were regular donors, while the last group (n = 30; M = 16, F = 14) were first-time donors or those who had not donated before. Following an overnight fast, 20 mL of venous blood was drawn from each subject. About 5 mL of this was put into sodium ethylenediaminetetraacetate (EDTA) specimen bottles for the full blood count parameters with Sysmex KX-21N hematology analyzer (made in Japan). The remaining 15 mL had serum separated for Sfr assay using enzyme-linked immunosorbent assay (ELISA) with a commercial assay kit manufactured by Teco Diagnostics. RESULTS Significant difference was found in the mean Sfr concentration of subjects with MetS (163 ± 136.92 ng/mL) and regular donors (41.46 ± 40.33 ng/mL), P = 0.001. The mean Sfr concentrations of subjects with MetS (163 ± 136.92 ng/mL) were also higher than that of first-time donors (102.46 ± 80.26 ng/mL), but it was not statistically significant, P = 0.053. The Hb concentrations of the three groups were not significantly different. CONCLUSION Sfr concentrations of regular donors were lower than that of subjects with MetS and first-time donors. The difference between regular donors and subjects with MetS was statistically significant. However, there is no significant difference in the Hb concentrations in the three groups. MetS is not associated with

  11. Lamprey hemoglobin. Structural basis of the bohr effect.

    PubMed

    Qiu, Y; Maillett, D H; Knapp, J; Olson, J S; Riggs, A F

    2000-05-01

    Lampreys, among the most primitive living vertebrates, have hemoglobins (Hbs) with self-association and ligand-binding properties very different from those that characterize the alpha(2)beta(2) tetrameric Hbs of higher vertebrates. Monomeric, ligated lamprey Hb self-associates to dimers and tetramers upon deoxygenation. Dissociation to monomers upon oxygenation accounts for the cooperative binding of O(2) and its pH dependence. Honzatko and Hendrickson (Honzatko, R. B., and Hendrickson, W. A. (1986) Proc. Natl. Acad. Sci. U. S. A 83, 8487-8491) proposed that the dimeric interface of the Hb resembles either the alpha(1)beta(2) interface of mammalian Hbs or the contacts in clam Hb where the E and F helices form the interface. Perutz (Perutz, M. F. (1989) Quart. Rev. Biophys. 2, 139- 236) proposed a version of the clam model in which the distal histidine swings out of the heme pocket upon deoxygenation to form a bond with a carboxyl group of a second monomer. The sedimentation behavior and oxygen equilibria of nine mutants of the major Hb component, PMII, from Petromyzon marinus have been measured to test these models. The results strongly support a critical role of the E helix and the AB corner in forming the subunit interface in the dimer and rule out the alpha(1)beta(2) model. The pH dependence of both the sedimentation equilibrium and the oxygen binding of the mutant E75Q indicate that Glu(75) is one of two groups responsible for the Bohr effect. Changing the distal histidine 73 to glutamine almost completely abolishes the self-association of the deoxy-Hb and causes a large increase in O(2) affinity. The recent x-ray crystallographic determination of the structure of deoxy lamprey Hb, reported after the completion of this work (Heaslet, H. A., and Royer, W. E. (1999) Structure 7, 517-526), shows that the dimer interface does involve the E helix and the AB corner, supporting the measurements and interpretations reported here.

  12. Site-Selective Glycosylation of Hemoglobin on Cys β93

    PubMed Central

    Zhang, Yalong; Bhatt, Veer S.; Sun, Guoyong; Wang, Peng G.; Palmer, Andre F.

    2009-01-01

    In this work, we describe the synthesis and characterization of a novel glycosylated hemoglobin (Hb) with high oxygen affinity as a potential Hb-based oxygen carrier. Site-selective glycosylation of bovine Hb was achieved by conjugating a lactose derivative to Cys 93 on the β subunit of Hb. LC-MS analysis indicates that the reaction was quantitative, with no unmodified Hb present in the reaction product. The glycosylation site was identified by chymotrypsin digestion of the glycosylated bovine Hb followed with LC-MS/MS and from the X-ray crystal structure of the glycosylated Hb. The chemical conjugation of the lactose derivative at Cys β93 yields an oxygen carrier with a high oxygen affinity (P50 of 4.94 mmHg) and low cooperativity coefficient (n) of 1.20. Asymmetric flow field-flow fractionation (AFFFF) coupled with multi-angle static light scattering (MASLS) was used to measure the absolute molecular weight of the glycosylated Hb. AFFFF-MASLS analysis indicates that glycosylation of Hb significantly altered the α2β2-αβ equilibrium compared to native Hb. Subsequent X-ray analysis of the glycosylated Hb crystal showed that the covalently linked lactose derivative is sandwiched between the β1 and α2 (and hence by symmetry the β2 and α1) subunits of the tetramer, and the interaction between the saccharide and amino acid residues located at the interface is apparently stabilized by hydrogen bonding interactions. The resultant structural analysis of the glycosylated Hb helps to explain the shift in the α2β2-αβ equilibrium in terms of the hydrogen bonding interactions at the β1α2/β2α1 interface. Taken together, all of these results indicate that it is feasible to site-specifically glycosylate Hb. This work has great potential in developing an oxygen carrier with defined chemistry that can target oxygen delivery to low pO2 tissues and organs. PMID:18925771

  13. Hemoglobin induces inflammation after preterm intraventricular hemorrhage by methemoglobin formation

    PubMed Central

    2013-01-01

    Background Cerebral intraventricular hemorrhage (IVH) is a major cause of severe neurodevelopmental impairment in preterm infants. To date, no therapy is available that prevents infants from developing serious neurological disability following IVH. Thus, to develop treatment strategies for IVH, it is essential to characterize the initial sequence of molecular events that leads to brain damage. In this study, we investigated extracellular hemoglobin (Hb) as a causal initiator of inflammation in preterm IVH. Methods Using a preterm rabbit pup model, we investigated the molecular mechanisms and events following IVH. We also characterized the concentrations of cell-free Hb metabolites and pro-inflammatory mediators in the cerebrospinal fluid (CSF) of preterm human infants and rabbit pups. Finally, Hb metabolites were evaluated as causal initiators of inflammation in primary rabbit astrocyte cell cultures. Results Following IVH in preterm rabbit pups, the intraventricular CSF concentration of cell-free methemoglobin (metHb) increased from 24 to 72 hours and was strongly correlated with the concentration of TNFα at 72 hours (r2 = 0.896, P <0.001). Also, the mRNA expression of TNFα, IL-1β, and Toll-like receptor-4 and TNFα protein levels were significantly increased in periventricular tissue at 72 hours, which was accompanied by extensive astrocyte activation (that is, glial fibrillary acidic protein (GFAP)staining). Furthermore, exposure of primary rabbit astrocyte cell cultures to metHb caused a dose-dependent increase in TNFα mRNA and protein levels, which was not observed following exposure to oxyhemoglobin (oxyHb) or hemin. Finally, a positive correlation (r2 = 0.237, P <0.03) between metHb and TNFα concentrations was observed in the CSF of preterm human infants following IVH. Conclusions Following preterm IVH, increased metHb formation in the intraventricular space induces expression of pro-inflammatory cytokines. Thus, the formation of metHb might be a

  14. Identification of the Presence of Variant Hemoglobin Using a Measurement of the Labile HbA1c (#C) Fraction.

    PubMed

    Koga, Masafumi; Inada, Shinya; Miyazaki, Ayako

    2016-07-01

    Labile HbA1c migrates in the #C fraction together with modified hemoglobin (such as carbamylated hemoglobin, acetaldehyde hemoglobin, and acetylated hemoglobin) when HbA1c is measured by Arkray's high-performance liquid chromatography (HPLC). It is assumed that most of the labile glycation products of variant hemoglobin do not migrate in #C fraction; in addition, a part of the stable glycation products of variant hemoglobin migrates in #C fraction. We hypothesized that subjects with variant hemoglobin are likely to show abnormally low or high values of #C fraction. In this study, we investigated this hypothesis. Twenty-one non-diabetic subjects with nine types of variant hemoglobin, and 103 non-diabetic subjects without variant hemoglobin were used. HbA1c and #C fraction were measured by Arkray's HPLC (HA-8180) using standard mode. The values of #C fraction in the control group were 1.75 ± 0.15% (range: 1.5-2.1%). The variant hemoglobin group reported #C fraction values of ≤1.3% in twelve subjects, ≥2.3% in five subjects, and within the reference range (1.4-2.2%) in three subjects. When the cutoff values of #C fraction were set at ≤1.3% and ≥2.3%, sensitivity and specificity were 86% and 100%, respectively. Most non-diabetic subjects with variant hemoglobin showed abnormal values of #C fraction. Measurement of #C fraction is a useful screening test for variant hemoglobin in non-diabetic subjects. PMID:27466298

  15. Human hemoglobin structural and functional alterations and heme degradation upon interaction with benzene: A spectroscopic study

    NASA Astrophysics Data System (ADS)

    Hosseinzadeh, Reza; Moosavi-Movahedi, Ali Akbar

    2016-03-01

    Here, the effect of benzene on hemoglobin structure, stability and heme prosthetic group integrity was studied by different methods. These included UV-vis absorption spectrophotometry, normal and synchronous fluorescence techniques, and differential scanning calorimetry (DSC). Our results indicated that benzene has high hemolytic potential even at low concentrations. The UV-vis spectroscopic results demonstrated that benzene altered both the globin chain and the heme prosthetic group of hemoglobin increasing met- and deoxy-Hb, while decreasing oxy-Hb. However, with increasing benzene the concentration of all species decreased due to heme destruction. The spectrophotometric results show that benzene has a high potential for penetrating the hydrophobic pocket of hemoglobin. These results were consistent with the molecular docking simulation results of benzene-hHb. Aggregation and thermal denaturation studies show that the increased benzene concentration induced hemoglobin aggregation with a decrease in stability, which is consistent with the DSC results. Conventional fluorescence spectroscopy revealed that the heme degradation species were produced in the presence of benzene. The results of constant wavelength synchronous fluorescence spectroscopy (CWSFS) indicated that at least five heme-degraded species were produced. Together, our results indicated that benzene has adverse effects on hemoglobin structure and function, and heme degradation.

  16. Erythropoietic kinetics in sheep studied by means of induced changes in hemoglobin phenotype

    PubMed Central

    Gabuzda, Thomas G.; Schuman, Marc A.; Silver, Ruth K.; Lewis, Hugh B.

    1968-01-01

    This investigation is concerned with the kinetics of the reciprocal relationship between sheep hemoglobin (Hb) A and Hb C formation in response to anemia. The relative synthesis of the hemoglobin types was assessed at various times in bone marrow erythroid cells incubated in vitro with 59Fe. The changeover from Hb A to Hb C formation lagged by about 3 days behind the development of anemia and was complete within about 11 days. After recovery from anemia the reciprocal change back to preanemic conditions proceeded at a much slower rate, Hb C formation gradually declining to unmeasurable levels over about 25 days. Infusions of plasma with high erythropoietin titre induced the formation of relatively large quantities of Hb C in erythroid cells of nonanemic sheep, demonstrating the central importance of a humoral mechanism in the change of expression of the hemoglobin genes. The following conclusions were drawn: hemoglobin phenotype is determined at a stem cell level. Erythroid stem cells appear to undergo gradual renewal. The identity of the plasma factor which induces Hb C formation is not yet known; it is not present in plasma from nonanemic sheep, and its production is not dependent upon hemoglobin genotype. If the plasma factor turns out to be erythropoietin, then this hormone must have an important influence on the pool of erythroid stem cells. Images PMID:5672611

  17. Multispectroscopic and calorimetric studies on the binding of the food colorant tartrazine with human hemoglobin.

    PubMed

    Basu, Anirban; Suresh Kumar, Gopinatha

    2016-11-15

    Interaction of the food colorant tartrazine with human hemoglobin was studied using multispectroscopic and microcalorimetric techniques to gain insights into the binding mechanism and thereby the toxicity aspects. Hemoglobin spectrum showed hypochromic changes in the presence of tartrazine. Quenching of the fluorescence of hemoglobin occurred and the quenching mechanism was through a static mode as revealed from temperature dependent and time-resolved fluorescence studies. According to the FRET theory the distance between β-Trp37 of hemoglobin and bound tartrazine was evaluated to be 3.44nm. Synchronous fluorescence studies showed that tartrazine binding led to alteration of the microenvironment around the tryptophans more in comparison to tyrosines. 3D fluorescence and FTIR data provided evidence for conformational changes in the protein on binding. Circular dichroism studies revealed that the binding led to significant loss in the helicity of hemoglobin. The esterase activity assay further complemented the circular dichroism data. Microcalorimetric study using isothermal titration calorimetry revealed the binding to be exothermic and driven largely by positive entropic contribution. Dissection of the Gibbs energy change proposed the protein-dye complexation to be dominated by non-polyelectrolytic forces. Negative heat capacity change also corroborated the involvement of hydrophobic forces in the binding process. PMID:27450339

  18. Detecting free hemoglobin in blood plasma and serum with luminescent terbium complexes.

    PubMed

    Morgner, Frank; Lecointre, Alexandre; Charbonnière, Loïc J; Löhmannsröben, Hans-Gerd

    2015-01-21

    Hemolysis, the rupturing of red blood cells, can result from numerous medical conditions (in vivo) or occur after collecting blood specimen or extracting plasma and serum out of whole blood (in vitro). In clinical laboratory practice, hemolysis can be a serious problem due to its potential to bias detection of various analytes or biomarkers. Here we present the first "mix-and-measure" method to assess the degree of hemolysis in biosamples using luminescence spectroscopy. Luminescent terbium complexes (LTC) were studied in the presence of free hemoglobin (Hb) as indicators for hemolysis in TRIS-buffer, and in fresh human plasma with absorption, excitation and emission measurements. Our findings indicate dynamic as well as resonance energy transfer (FRET) between the LTC and the porphyrin ligand of hemoglobin. This transfer leads to a decrease in luminescence intensity and decay time even at nanomolar hemoglobin concentrations either in buffer or plasma. Luminescent terbium complexes are very sensitive to free hemoglobin in buffer and blood plasma. Due to the instant change in luminescence properties of the LTC in presence of Hb it is possible to access the concentration of hemoglobin via spectroscopic methods without incubation time or further treatment of the sample thus enabling a rapid and sensitive detection of hemolysis in clinical diagnostics.

  19. Quantitative Absorption Cytometry for Measuring Red Blood Cell Hemoglobin Mass and Volume

    PubMed Central

    Schonbrun, Ethan; Malka, Roy; Di Caprio, Giuseppe; Schaak, Diane; Higgins, John M.

    2015-01-01

    We present an optical system, called the quantitative absorption cytometer (QAC), to measure the volume and hemoglobin mass of red blood cells flowing through a microfluidic channel. In contrast to clinical hematology analyzers, where cells are sphered in order for both volume and hemoglobin to be measured accurately, the QAC measures cells in their normal physiological shape. Human red blood cells are suspended in a refractive index-matching absorbing buffer, driven through a microfluidic channel, and imaged using a transmission light microscope onto a color camera. A red and a blue LED illuminate cells and images at each color are used to independently retrieve cell volume and hemoglobin mass. This system shows good agreement with red blood cell indices retrieved by a clinical hematology analyzer and in fact measures a smaller coefficient of variation of hemoglobin concentration. In addition to cell indices, the QAC returns height and mass maps of each measured cell. These quantitative images are valuable for analyzing the detailed morphology of individual cells as well as statistical outliers found in the data. We also measured red blood cells in hypertonic and hypotonic buffers to quantify the correlation between volume and hemoglobin mass under osmotic stress. Because this method is invariant to cell shape, even extremely nonspherical cells in hypertonic buffers can be measured accurately. PMID:24677669

  20. Osmotic and diffusive properties of intracellular water in camel erythrocytes: effect of hemoglobin crowdedness.

    PubMed

    Bogner, Peter; Miseta, Attila; Berente, Zoltan; Schwarcz, Attila; Kotek, Gyula; Repa, Imre

    2005-09-01

    Camel erythrocytes have exceptional osmotic resistance and is believed to be due to augmented water-binding associated with the high hydrophilicity of camel hemoglobin. In practical terms this means that the proportion of osmotically non-removable water in camel erythrocytes is nearly 3-fold greater than that in human erythrocytes (approximately 65 vs approximately 20%). The relationship between water diffusion and the osmotic characteristics of intracellular water is the subject of this report. The amount of osmotically inactive water is 2-fold greater in camel hemoglobin solution in vitro compared to that of human, but water diffusion does not differ in camel and human hemoglobin solutions. However, the evaluation of water diffusion by magnetic resonance measurements in camel erythrocytes revealed approximately 15% lower apparent diffusion coefficient (ADC) compared with human erythrocytes. When human erythrocytes were dehydrated to the level of camel erythrocytes, their osmotic and water diffusion properties were similar. These results show that a lower ADC is associated with a more pronounced increase in osmotically inactive water fraction. It is proposed that increased hemoglobin hydrophilicity allows not only augmented water-binding, but also a closer hemoglobin packaging in vivo, which in turn is associated with slower ADC and increased osmotic resistance. PMID:15951204

  1. Monitor hemoglobin concentration and oxygen saturation in living mouse tail using photoacoustic CT scanner

    NASA Astrophysics Data System (ADS)

    Liu, Bo; Kruger, Robert; Reinecke, Daniel; Stantz, Keith M.

    2010-02-01

    Purpose: The purpose of this study is to use PCT spectroscopy scanner to monitor the hemoglobin concentration and oxygen saturation change of living mouse by imaging the artery and veins in a mouse tail. Materials and Methods: One mouse tail was scanned using the PCT small animal scanner at the isosbestic wavelength (796nm) to obtain its hemoglobin concentration. Immediately after the scan, the mouse was euthanized and its blood was extracted from the heart. The true hemoglobin concentration was measured using a co-oximeter. Reconstruction correction algorithm to compensate the acoustic signal loss due to the existence of bone structure in the mouse tail was developed. After the correction, the hemoglobin concentration was calculated from the PCT images and compared with co-oximeter result. Next, one mouse were immobilized in the PCT scanner. Gas with different concentrations of oxygen was given to mouse to change the oxygen saturation. PCT tail vessel spectroscopy scans were performed 15 minutes after the introduction of gas. The oxygen saturation values were then calculated to monitor the oxygen saturation change of mouse. Results: The systematic error for hemoglobin concentration measurement was less than 5% based on preliminary analysis. Same correction technique was used for oxygen saturation calculation. After correction, the oxygen saturation level change matches the oxygen volume ratio change of the introduced gas. Conclusion: This living mouse tail experiment has shown that NIR PCT-spectroscopy can be used to monitor the oxygen saturation status in living small animals.

  2. Hemoglobin concentrations in waders vary with their strategies of migration: a comparative analysis.

    PubMed

    Minias, Piotr; Kaczmarek, Krzysztof; Włodarczyk, Radosław; Janiszewski, Tomasz

    2013-05-01

    The aim of this study was to determine whether blood oxygen capacity of waders varies with respect to migration at both inter-specific and individual level. To verify this hypothesis we measured hemoglobin concentration in 875 waders from 14 species during their autumn migration through central Poland. In most of the species we found an increase in the hemoglobin levels along with increasing fat loads during the stopover period, which suggests that individual birds are able to elevate their oxygen-carrying capacity of blood prior to departure on a migratory flight. Positive relationship between hemoglobin concentrations of waders and their fat loads was confirmed at the inter-specific level by the comparative analysis of independent contrasts. Comparative analysis also demonstrated that hemoglobin concentrations were positively related with theoretical flight range and mean refueling rate during stopovers. The results indicate that species traveling according to the strategy of energy-minimization (short-distance migrants, low fat reserves, low refueling rates) have lower blood oxygen capacity in comparison to time-selected species (long-distance migrants, high fat reserves, high refueling rates). It remains uncertain whether high hemoglobin levels in long-distance migrants are a fixed evolutionary trait or a temporal physiological adaptation associated with carrying considerable fat load. PMID:23425637

  3. Molecular mechanism of AHSP-mediated stabilization of alpha-hemoglobin.

    PubMed

    Feng, Liang; Gell, David A; Zhou, Suiping; Gu, Lichuan; Kong, Yi; Li, Jianqing; Hu, Min; Yan, Nieng; Lee, Christopher; Rich, Anne M; Armstrong, Robert S; Lay, Peter A; Gow, Andrew J; Weiss, Mitchell J; Mackay, Joel P; Shi, Yigong

    2004-11-24

    Hemoglobin A (HbA), the oxygen delivery system in humans, comprises two alpha and two beta subunits. Free alpha-hemoglobin (alphaHb) is unstable, and its precipitation contributes to the pathophysiology of beta thalassemia. In erythrocytes, the alpha-hemoglobin stabilizing protein (AHSP) binds alphaHb and inhibits its precipitation. The crystal structure of AHSP bound to Fe(II)-alphaHb reveals that AHSP specifically recognizes the G and H helices of alphaHb through a hydrophobic interface that largely recapitulates the alpha1-beta1 interface of hemoglobin. The AHSP-alphaHb interactions are extensive but suboptimal, explaining why beta-hemoglobin can competitively displace AHSP to form HbA. Remarkably, the Fe(II)-heme group in AHSP bound alphaHb is coordinated by the distal but not the proximal histidine. Importantly, binding to AHSP facilitates the conversion of oxy-alphaHb to a deoxygenated, oxidized [Fe(III)], nonreactive form in which all six coordinate positions are occupied. These observations reveal the molecular mechanisms by which AHSP stabilizes free alphaHb.

  4. Hemoglobin adducts of N-substituted aryl compounds in exposure control and risk assessment.

    PubMed

    Neumann, H G; Birner, G; Kowallik, P; Schütze, D; Zwirner-Baier, I

    1993-03-01

    Arylamines, nitroarenes, and azo dyes yield a common type of metabolite, the nitroarene, which produces a hydrolyzable adduct with protein and is closely related to the critical, ultimate toxic and genotoxic metabolite. The target dose as measured by hemoglobin adducts in erythrocytes reflects not only the actual uptake from the environment but also an individual's capacity for metabolic activation and is therefore an improved dosimeter for human exposure. The usefulness of hemoglobin adducts in molecular epidemiology is now widely recognized. With regard to risk assessment, many questions need to be answered. The described experiments in rats address some of these questions. The relationship between binding to hemoglobin in erythrocytes and to proteins in plasma has been found to vary considerably for a number of diamines. The fraction of hydrolyzable adducts out of the total protein adducts formed also varies in both compartments. This indicates that the kind of circulating metabolites and their availability in different compartments is compound specific. This has to do with the complex pattern of competing metabolic pathways, and the role of N-acetylation and deacetylation is emphasized. An example of nonlinear dose dependence adds to the complexity. Analysis of hemoglobin adducts reveals interesting insights into prevailing pathways, which not only apply to the chemical, but may also be useful to assess an individual's metabolic properties. In addition, it is demonstrated that the greater part of erythrocytes and benzidine-hemoglobin adducts are eliminated randomly in rats, i.e., following first-order kinetics.

  5. Molecular Mechanism of AHSP-Mediated Stabilization of Alpha-Hemoglobin

    SciTech Connect

    Feng,L.; Gell, D.; Zhou, S.; Gu, L.; Kong, Y.; Li, J.; Hu, M.; Yan, N.; Lee, C.; et al.

    2005-01-01

    Hemoglobin A (HbA), the oxygen delivery system in humans, comprises two alpha and two beta subunits. Free alpha-hemoglobin (alphaHb) is unstable, and its precipitation contributes to the pathophysiology of beta thalassemia. In erythrocytes, the alpha-hemoglobin stabilizing protein (AHSP) binds alphaHb and inhibits its precipitation. The crystal structure of AHSP bound to Fe(II)-alphaHb reveals that AHSP specifically recognizes the G and H helices of alphaHb through a hydrophobic interface that largely recapitulates the alpha1-beta1 interface of hemoglobin. The AHSP-alphaHb interactions are extensive but suboptimal, explaining why beta-hemoglobin can competitively displace AHSP to form HbA. Remarkably, the Fe(II)-heme group in AHSP bound alphaHb is coordinated by the distal but not the proximal histidine. Importantly, binding to AHSP facilitates the conversion of oxy-alphaHb to a deoxygenated, oxidized [Fe(III)], nonreactive form in which all six coordinate positions are occupied. These observations reveal the molecular mechanisms by which AHSP stabilizes free alphaHb.

  6. Red blood with blue-blood ancestry: Intriguing structure of a snail hemoglobin

    PubMed Central

    Lieb, Bernhard; Dimitrova, Konstantina; Kang, Hio-Sun; Braun, Sabrina; Gebauer, Wolfgang; Martin, Andreas; Hanelt, Ben; Saenz, Steven A.; Adema, Coen M.; Markl, Jürgen

    2006-01-01

    The phylogenetic enigma of snail hemoglobin, its isolated occurrence in a single gastropod family, the Planorbidae, and the lack of sequence data, stimulated the present study. We present here the complete cDNA and predicted amino acid sequence of two hemoglobin polypeptides from the planorbid Biomphalaria glabrata (intermediate host snail for the human parasite Schistosoma mansoni). Both isoforms contain 13 different, cysteine-free globin domains, plus a small N-terminal nonglobin “plug” domain with three cysteines for subunit dimerization (total Mr ≈ 238 kDa). We also identified the native hemoglobin molecule and present here a preliminary 3D reconstruction from electron microscopical images (3 nm resolution); it suggests a 3 × 2-mer quaternary structure (Mr ≈ 1.43 MDa). Moreover, we identified a previously undescribed rosette-like hemolymph protein that has been mistaken for hemoglobin. We also detected expression of an incomplete hemocyanin as trace component. The combined data show that B. glabrata hemoglobin evolved from pulmonate myoglobin, possibly to replace a less-efficient hemocyanin, and reveals a surprisingly simple evolutionary mechanism to create a high molecular mass respiratory protein from 78 similar globin domains. PMID:16877545

  7. Gene cooption and convergent evolution of oxygen transport hemoglobins in jawed and jawless vertebrates

    PubMed Central

    Hoffmann, Federico G.; Opazo, Juan C.; Storz, Jay F.

    2010-01-01

    Natural selection often promotes evolutionary innovation by coopting preexisting genes for new functions, and this process may be greatly facilitated by gene duplication. Here we report an example of cooptive convergence where paralogous members of the globin gene superfamily independently evolved a specialized O2 transport function in the two deepest branches of the vertebrate family tree. Specifically, phylogenetic evidence demonstrates that erythroid-specific O2 transport hemoglobins evolved independently from different ancestral precursor proteins in jawed vertebrates (gnathostomes) and jawless fish (cyclostomes, represented by lamprey and hagfish). A comprehensive phylogenetic analysis of the vertebrate globin gene superfamily revealed that the erythroid hemoglobins of cyclostomes are orthologous to the cytoglobin protein of gnathostome vertebrates, a hexacoordinate globin that has no O2 transport function and that is predominantly expressed in fibroblasts and related cell types. The phylogeny reconstruction also revealed that vertebrate-specific globins are grouped into four main clades: (i) cyclostome hemoglobin + cytoglobin, (ii) myoglobin + globin E, (iii) globin Y, and (iv) the α- and β-chain hemoglobins of gnathostomes. In the hemoglobins of gnathostomes and cyclostomes, multisubunit quaternary structures provide the basis for cooperative O2 binding and allosteric regulation by coupling the effects of ligand binding at individual subunits with interactions between subunits. However, differences in numerous structural details belie their independent origins. This example of convergent evolution of protein function provides an impressive demonstration of the ability of natural selection to cobble together complex design solutions by tinkering with different variations of the same basic protein scaffold. PMID:20660759

  8. Penta- and hexa-coordinate ferric hemoglobins display distinct pH titration profiles measured by Soret peak shifts.

    PubMed

    Uppal, Sheetal; Kumar, Amit; Shandilya, Manish; Mukhi, Nitika; Singh, Amit Kumar; Kateriya, Suneel; Kaur, Jagreet; Kundu, Suman

    2016-10-01

    Hemoglobins with diverse characteristics have been identified in all kingdoms of life. Their ubiquitous presence indicates that these proteins play important roles in physiology, though function for all hemoglobins are not yet established with certainty. Their physiological role may depend on their ability to bind ligands, which in turn is dictated by their heme chemistry. However, we have an incomplete understanding of the mechanism of ligand binding for these newly discovered hemoglobins and the measurement of their kinetic parameters depend on their coordination at the heme iron. To gain insights into their functional role, it is important to categorize the new hemoglobins into either penta- or hexa-coordinated varieties. We demonstrate that simple pH titration and absorbance measurements can determine the coordination state of heme iron atom in ferric hemoglobins, thus providing unambiguous information about the classification of new globins. This method is rapid, sensitive and requires low concentration of protein. Penta- and hexa-coordinate hemoglobins displayed distinct pH titration profiles as observed in a variety of hemoglobins. The pentacoordinate distal histidine mutant proteins of hexacoordinate hemoglobins and ligand-bound hexacoordinate forms of pentacoordinate hemoglobins reverse the pH titration profiles, thus validating the sensitivity of this spectroscopic technique.

  9. Penta- and hexa-coordinate ferric hemoglobins display distinct pH titration profiles measured by Soret peak shifts.

    PubMed

    Uppal, Sheetal; Kumar, Amit; Shandilya, Manish; Mukhi, Nitika; Singh, Amit Kumar; Kateriya, Suneel; Kaur, Jagreet; Kundu, Suman

    2016-10-01

    Hemoglobins with diverse characteristics have been identified in all kingdoms of life. Their ubiquitous presence indicates that these proteins play important roles in physiology, though function for all hemoglobins are not yet established with certainty. Their physiological role may depend on their ability to bind ligands, which in turn is dictated by their heme chemistry. However, we have an incomplete understanding of the mechanism of ligand binding for these newly discovered hemoglobins and the measurement of their kinetic parameters depend on their coordination at the heme iron. To gain insights into their functional role, it is important to categorize the new hemoglobins into either penta- or hexa-coordinated varieties. We demonstrate that simple pH titration and absorbance measurements can determine the coordination state of heme iron atom in ferric hemoglobins, thus providing unambiguous information about the classification of new globins. This method is rapid, sensitive and requires low concentration of protein. Penta- and hexa-coordinate hemoglobins displayed distinct pH titration profiles as observed in a variety of hemoglobins. The pentacoordinate distal histidine mutant proteins of hexacoordinate hemoglobins and ligand-bound hexacoordinate forms of pentacoordinate hemoglobins reverse the pH titration profiles, thus validating the sensitivity of this spectroscopic technique. PMID:27449132

  10. IV. HEMOGLOBIN INJECTIONS AND CONSERVATION OF PIGMENT BY KIDNEY, LIVER AND SPLEEN : THE INFLUENCE OF DIET AND BLEEDING.

    PubMed

    Newman, W V; Whipple, G H

    1932-03-31

    When the minimal renal threshold for blood hemoglobin is exceeded there is observed a deposit of iron staining pigment in the epithelium of the renal convoluted tubules. At a certain point this epithelium cannot take up more hemoglobin and this coincides with the minimal renal threshold level. When the injections of blood hemoglobin are kept below the minimal renal threshold level we note a complete absence of iron staining pigment in the renal tubular epithelium. Given a deposit of iron staining pigment in the tubular epithelium, it will slowly disappear during rest periods with no hemoglobin injections. Anemia due to bleeding will accelerate this removal of pigment from the renal epithelium and this indicates a conservation of material by the kidney for use in construction of new hemoglobin. Pigment giving a positive stain for iron will be found in the liver and spleen when hemoglobin injections are given, regardless of the renal threshold. Removal of this pigment is accelerated by anemia due to bleeding and as a rule an anemia period of 2 months at a level of 1/3 normal (40 to 50 per cent hemoglobin) will render the spleen, liver and kidney free from iron staining pigment. Pigment giving a positive iron stain is frequently observed in the mesenteric and lower retroperitoneal lymph glands. This is merely a drainage of pigment and phagocytes including pigment from some organ in which the pigment deposit was primary. In stock dogs in this laboratory the hemoglobin level is quite high when the animals are in a perfectly normal state. The blood hemoglobin averages 120 to 150 per cent hemoglobin. In such dogs iron staining pigment in the spleen is a common finding and on occasion is observed in the liver. To establish an accurate base line for the study of iron and iron staining pigment storage due to diet intake one must submit these dogs to a preliminary anemia period of at least 2 months. Muscle hemoglobin has a very low renal threshold and escapes freely into the

  11. History-Adjusted Marginal Structural Analysis of the Association between Hemoglobin Variability and Mortality among Chronic Hemodialysis Patients

    PubMed Central

    Brunelli, Steven M.; Joffe, Marshall M.; Israni, Rubeen K.; Yang, Wei; Fishbane, Steven; Berns, Jeffrey S.; Feldman, Harold I.

    2008-01-01

    Background and objectives: Hemoglobin variability is common among dialysis patients, and has been associated with increased mortality. The causal nature of this association has been difficult to ascertain because of potential time-dependent confounding, for which traditional statistical methods do not control. Design, settings, participants, & measurements: A retrospective cohort of 34,963 Fresenius Medical care dialysis patients from 1996 was assembled. Hemoglobin variability, absolute hemoglobin level, and temporal hemoglobin trend were measured over rolling 6-mo exposure windows. Their association with mortality was estimated using history-adjusted marginal structural analysis that adjusts for time-dependent confounding by applying weights to observations inversely related to the predictability of observed levels of hemoglobin. Results: In the primary analysis, each g/dl increase in hemoglobin variability was associated with an adjusted hazard ratio (HR) [95% confidence interval (CI)] for all-cause mortality of 1.93 (1.20 to 3.10). Neither higher absolute hemoglobin level nor increasing hemoglobin trend were significantly associated with mortality; adjusted HR (95% CI) 0.85 (0.64 to 1.11) and 0.60 (0.25 to 1.45), respectively. Conclusions: Marginal structural analysis demonstrates that hemoglobin variability is associated with increased mortality among chronic hemodialysis patients, and that this effect is more pronounced than appreciated using standard statistical techniques that do not take time-dependent confounding into account. PMID:18337553

  12. Acute Splenic Sequestration Crisis in a 70-Year-Old Patient With Hemoglobin SC Disease

    PubMed Central

    Squiers, John J.; Edwards, Anthony G.; Parra, Alberto; Hofmann, Sandra L.

    2016-01-01

    A 70-year-old African American female with a past medical history significant for chronic bilateral shoulder pain and reported sickle cell trait presented with acute-onset bilateral thoracolumbar pain radiating to her left arm. Two days after admission, Hematology was consulted for severely worsening microcytic anemia and thrombocytopenia. Examination of the patient’s peripheral blood smear from admission revealed no cell sickling, spherocytes, or schistocytes. Some targeting was noted. A Coombs test was negative. The patient was eventually transferred to the medical intensive care unit in respiratory distress. Hemoglobin electrophoresis confirmed a diagnosis of hemoglobin SC disease. A diagnosis of acute splenic sequestration crisis complicated by acute chest syndrome was crystallized, and red blood cell exchange transfusion was performed. Further research is necessary to fully elucidate the pathophysiology behind acute splenic sequestration crisis, and the role of splenectomy to treat hemoglobin SC disease patients should be better defined. PMID:27047980

  13. Seasonal influence on hematologic values and hemoglobin electrophoresis in Brazilian boa constrictor amarali.

    PubMed

    Machado, Carla C; Silva, Luis F N; Ramos, Paulo R R; Takahira, Regina K

    2006-12-01

    As ectothermic animals, snakes depend exclusively on the environment for proper temperature maintenance, which may greatly influence their activity. Twenty-five adult Boa constrictor amarali snakes maintained in captivity were used to determine the influence of seasons on their hematologic values and electrophoretic profile of hemoglobin. A complete blood cell count (CBC) and examination for hemoparasites were performed in the summer and winter of 2004. Hemoglobin was stored for later electrophoresis. Significant differences (P < 0.05) were obtained in RBC, WBC, lymphocyte, thrombocyte, and monocyte counts, demonstrating the importance of the period of the year in the interpretation of reference values in these animals. Two snakes were detected with blood parasites (Hepatozoon sp.) in the winter and four in the summer, although it appears that their presence did not cause any significant alterations in the CBC. The electrophoretic analysis of the samples demonstrated two-four hemoglobin bands in this species.

  14. Carnivora: the primary structure of the Pacific Walrus (Odobenus rosmarus divergens, Pinnipedia) hemoglobin.

    PubMed

    Lin, H X; Kleinschmidt, T; Johnson, M L; Braunitzer, G

    1989-02-01

    The primary structure of the alpha- and beta-chains of the hemoglobin from the Pacific Walrus (Odobenus rosmarus divergens, Pinnipedia) is presented. Sequence analysis revealed only one hemoglobin component whereas two bands were found in polyacrylamide gel electrophoresis. The globin chains were separated by high-performance liquid chromatography and the sequences determined by automatic liquid- and gas-phase sequencing of the chains and their tryptic peptides. The alpha-chains show 20 and the beta-chains 12 exchanges compared to the corresponding human chains. In the alpha-chains one heme- and two alpha 1/beta 1-contacts were exchanged whereas in the beta-chains one alpha 1/beta 1-, one alpha 1/beta 2-and one heme-contact are substituted. Compared to Harbour Seal (Phoca vitulina) the Walrus hemoglobin shows 9 amino-acid replacements in the alpha-chains and 5 in the beta-chains. The relation between Pinnipedia and Arctoidea is discussed.

  15. Triplet state magnetic resonance and fluorescence spectroscopy of metal-substituted hemoglobins.

    PubMed Central

    Polm, M W; Schaafsma, T J

    1997-01-01

    Fluorescence detected magnetic resonance (FDMR) spectra detected at 596 nm of zinc-substituted hemoglobins at 4.2 K show a split D-E transition, which is not observed for zinc protoporphyrins ligated by methylimidazole in glasses. Incorporation of the zinc heme into the globin pocket is also accompanied by a blue shift of the fluorescence of 20 nm at 4.2 K. FDMR spectra recorded at 576 nm do not show the D-E splitting. The D-E splitting and the huge blue shift are not observed for the magnesium-substituted hemoglobins. Fluorescence measurements at 4.2 K and 77 K, and EPR measurements at 110 K, were carried out to obtain information about the ligation states of the zinc and magnesium protoporphyrins in glasses and in hemoglobin. The results are explained by considering ligation effects and distortion of the porphyrin plane. Images FIGURE 12 PMID:8994622

  16. Reaction of nitric oxide with heme proteins and model compounds of hemoglobin

    SciTech Connect

    Sharma, V.S.; Traylor, T.G.; Gardiner, R.; Mizukami, H.

    1987-06-30

    Rates for the reaction of nitric oxide with several ferric heme proteins and model compounds have been measured. The NO combination rates are markedly affected by the presence or absence of distal histidine. Elephant myoglobin in which the E7 distal histidine has been replaced by glutamine reacts with NO 500-1000 times faster than do the native hemoglobins or myoglobins. By contrast, there is not difference in the CO combination rate constants of sperm whale and elephant myoglobins. Studies on ferric model compounds for the R and T states of hemoglobin indicate that their NO combination rate constants are similar to those observed for the combination of CO with the corresponding ferro derivatives. The last observation suggests that the presence of an axial water molecule at the ligand binding site of ferric hemoglobin A prevents it from exhibiting significant cooperativity in its reactions with NO.

  17. Surface-enhanced Raman spectra of hemoglobin for esophageal cancer diagnosis

    NASA Astrophysics Data System (ADS)

    Zhou, Xue; Diao, Zhenqi; Fan, Chunzhen; Guo, Huiqiang; Xiong, Yang; Tang, Weiyue

    2014-03-01

    Surface-enhanced Raman scattering (SERS) spectra of hemoglobin from 30 esophageal cancer patients and 30 healthy persons have been detected and analyzed. The results indicate that, there are more iron ions in low spin state and less in high for the hemoglobin of esophageal cancer patients than normal persons, which is consistent with the fact that it is easier to hemolyze for the blood of cancer patients. By using principal component analysis (PCA) and discriminate analysis, we can get a three-dimensional scatter plot of PC scores from the SERS spectra of healthy persons and cancer patients, from which the two groups can be discriminated. The total accuracy of this method is 90%, while the diagnostic specificity is 93.3% and sensitivity is 86.7%. Thus SERS spectra of hemoglobin analysis combined with PCA may be a new technique for the early diagnose of esophageal cancer.

  18. [Development and challenge of modified hemoglobins as red blood cell substitutes].

    PubMed

    Lu, Xiu-Ling

    2006-01-01

    The problems of blood shortage and the virus infection risk of blood transfusion have promoted the study of blood substitutes. Modified hemoglobin has become the focus of the challenges research because of its excellent oxygen carrying ability. To overcome the toxicity effect on direct use of purified native hemoglobin, various modification technologies have been developed, including diaspirin cross-linking, glutaraldehyde polymerization, O-raffinose polymerization, polyethylene glycol conjugation, liposome encapsulation and biodegradable polymer encapsulation. Some of the products have been in clinical trials, and one of the products has been approved in a country for clinical use. Research on red blood cell substitutes in China has also developed fast. This paper provides an overview of the history and current status in development of different hemoglobin-based red blood cell substitutes, especially the problems encountered, the challenges faced, and the prospects in future.

  19. Red cell substitutes from hemoglobin--do we start all over again?

    PubMed

    Kluger, Ronald

    2010-08-01

    Red cells are the oxygen-carrying components of blood. In modern medical practice, transfusions are given as suspensions of type-matched red cells in saline to replace lost blood, preventing organ damage and allowing for recovery. Since red cells cannot be stored for more than about 40 days and because they can transmit infections, alternative materials for transfusions were developed to replace the oxygenation function of the red cells. One approach involves chemically stabilizing hemoglobin, the oxygen-carrying protein of the red cell, while also adjusting its oxygenation properties to replicate that of the red cell. Evaluation of clinical trials of all products led to the conclusion that none that were tested would be suitable for clinical use [Natanson C, Kern SJ, Lurie P, Banks SM, Wolfe SM: Cell-free hemoglobin-based blood substitutes and risk of myocardial infarction and death: a meta-analysis. J Am Med Assoc 2008, 299:2304-2312]. Most notably, the materials increased blood pressure and some were associated with increased risk of heart attacks. More recently, it was found that materials from covalent addition of polyethylene glycol polymers (PEG) to hemoglobin do not elicit the undesired effects on blood pressure [Vandegriff K, Bellelli A, Samaja M, Malavalli A, Brunori M, Winslow RM: Rates of NO binding to MP4, a non-hypertensive polyethylene glycol-conjugated hemoglobin. FASEB J 2003, 17:A183; Vandegriff KD, Malavalli A, Wooldridge J, Lohman J, Winslow RM: MP4: a new nonvasoactive PEG-Hb conjugate. Transfusion 2003, 43:509-516]. Also, materials with higher oxygen affinity than red cells are able to provide oxygenation at the sites in capillaries that have the most critical need for oxygen [Villela NR, Cabrales P, Tsai AG, Intaglietta M: Microcirculatory effects of changing blood hemoglobin oxygen affinity during hemorrhagic shock resuscitation in an experimental model. Shock 2009, 31:645-652]. It had been considered that the origin of the negative effects

  20. Characteristics of High-Resolution Hemoglobin Measurement Microchip Integrated with Signal Processing Circuit

    NASA Astrophysics Data System (ADS)

    Noda, Toshihiko; Takao, Hidekuni; Ashiki, Mitsuaki; Ebi, Hiroyuki; Sawada, Kazuaki; Ishida, Makoto

    2004-04-01

    In this study, a microchip for measurement of hemoglobin in human blood has been proposed, fabricated and evaluated. The measurement principle of hemoglobin is based on the “cyanmethemoglobin method” that calculates the cyanmethemoglobin concentration by absorption photometry. A glass/silicon/silicon structure was used for the microchip. The middle silicon layer includes flow channels, and 45° mirrors formed at each end of the flow channels. Photodiodes and metal oxide semiconductor (MOS) integrated circuits were fabricated on the bottom silicon layer. The performance of the microchip for hemoglobin measurement was evaluated using a solution of red food color instead of a real blood sample. The fabricated microchip exhibited a similar performance to a nonminiaturized absorption cell which has the same optical path length. Signal processing output varied with solution concentration from 5.32 V to 5.55 V with very high stability due to differential signal processing.

  1. Free radical-mediated platelet activation by hemoglobin released from red blood cells.

    PubMed

    Iuliano, L; Violi, F; Pedersen, J Z; Praticò, D; Rotilio, G; Balsano, F

    1992-12-01

    It is known that the rate of thrombus formation depends on interaction between platelets and erythrocytes, but the mechanism of this process has remained obscure. We here show that nanomolar levels of hemoglobin released from damaged red blood cells can induce platelet aggregation. The molecular mechanism is not receptor-based, but involves oxidation of oxyhemoglobin by platelet-derived hydrogen peroxide, with subsequent generation of a small unknown free radical species, detected by ESR spectroscopy. Methemoglobin and carbon monoxide-treated hemoglobin are unable to cause platelet activation or radical formation. The aggregation of platelets induced by hemoglobin is completely blocked by catalase or radical scavengers. These findings indicate a role for a novel extracellular free radical second messenger in the activation of platelets.

  2. Hemoglobin-Based Oxygen Carrier for Traumatic Hemorrhagic Shock Treatment in a Jehovah’s Witness

    PubMed Central

    Posluszny, Joseph A.; Napolitano, Lena M.

    2016-01-01

    Introduction: Treatment of severe hemorrhagic shock due to acute blood loss from traumatic injuries in a Jehovah’s witness (JW) trauma patient is very challenging since hemostatic blood product resuscitation is limited by refusal of the transfusion of allogeneic blood products. Case Presentation: We describe a multifaceted approach to the clinical care of a severely anemic JW trauma patient including the early administration of a bovine hemoglobin-based oxygen carrier (HBOC) as a bridge to resolution of critical anemia (nadir hemoglobin 3.9 g/dL). Hemoglobin-based oxygen carrier infusions were used to supplement oxygen delivery until endogenous erythropoiesis could restore adequate red blood cell mass. Subsequent endogenous bone marrow recovery was supported by early administration of high-dose erythropoiesis-stimulating agents and iron supplementation. Conclusions: Early HBOC administration can be used in the treatment of severe hemorrhagic shock in trauma patients who refuse allogeneic blood.

  3. The primary structure of pale-throated three-toed sloth (Bradypus tridactylus, Xenarthra) hemoglobin.

    PubMed

    Kleinschmidt, T; März, J; Braunitzer, G

    1989-04-01

    The hemoglobin of the Pale-Throated Three-Toed Sloth (Bradypus tridactylus, Xenarthra) was separated into two components (ratio 4:1) with identical amino-acid analyses for the alpha- and beta-chains. The primary structures of both chains from the major component are given. They could be isolated by chromatography on carboxymethyl cellulose CM-52. The sequences have been determined by automatic Edman degradation of the native chains and their tryptic peptides. The comparison with human hemoglobin showed 27 substitutions in the alpha-chains and 33 in the beta-chains. In the alpha-chains one amino-acid exchange involves an alpha 1/beta 1-contact. In the beta-chains two heme- and four alpha 1/beta 1-contacts are substituted. The hemoglobin of the Sloth is compared to that of the Nine-Banded Armadillo (Dasypus novemcinctus), another representative of the order Xenerthra.

  4. [Noninvasive total hemoglobin monitoring based on multiwave spectrophotometry in obstetrics and gynecology].

    PubMed

    Pyregov, A V; Ovechkin, A Iu; Petrov, S V

    2012-01-01

    Results of prospective randomized comparative research of 2 total hemoglobin estimation methods are presented. There were laboratory tests and continuous noninvasive technique with multiwave spectrophotometry on the Masimo Rainbow SET. Research was carried out in two stages. At the 1st stage (gynecology)--67 patients were included and in second stage (obstetrics)--44 patients during and after Cesarean section. The standard deviation of noninvasive total hemoglobin estimation from absolute values (invasive) was 7.2 and 4.1%, an standard deviation in a sample--5.2 and 2.7 % in gynecologic operations and surgical delivery respectively, that confirms lack of reliable indicators differences. The method of continuous noninvasive total hemoglobin estimation with multiwave spectrophotometry on the Masimo Rainbow SET technology can be recommended for use in obstetrics and gynecology.

  5. The effect of gamma-rays on the hemoglobin of whole-body irradiated mice

    NASA Astrophysics Data System (ADS)

    Ashry, H. A.; Selim, N. S.; El-Behay, A. Z.

    1994-07-01

    Changes in the UV-visible absorption spectrum of mouse hemoglobin as a result of whole body irradiation were studied. White albino adult mice were exposed to a Cs-137 γ-source at a dose rate of 47.5 Gy/h to different absorbed dose values ranging from 1 to 8 Gy. Blood specimens were taken 24 h after irradiation. The UV-visible absorption spectra of hemoglobin of irradiated and control mice were measured in the wavelength range from 200 to 700 nm. The obtained results showed significant changes in the bands measured at 340 nm, in the Soret band measured at 410 nm, also, the α- and β-bands measured at 537 and 572 nm showed significant decrease in intensity with the absorbed dose increase. The absorbance measured at 630 nm showed no significant changes. The radiation effect on the animal hemoglobin was discussed on the basis of the obtained results.

  6. Monitoring of environmental cancer initiators through hemoglobin adducts by a modified Edman degradation method

    SciTech Connect

    Toernqvist, M.M.; Mowrer, J.; Jensen, S.; Ehrenberg, L.

    1986-04-01

    Tissue doses of cancer initiators/mutagens are suitably monitored through hemoglobin adducts formed in vivo, but the use of this method has been hampered by a lack of sufficiently simple and fast procedures. It was previously observed that when the N-terminal amino acid in hemoglobin, valine, is alkylated it is cleaved off by the Edman sequencing reagent, phenyl isothiocyanate, in the neutral-alkaline coupling medium, as opposed to the acidic medium required by normal amino acids. Based on this principle, conditions for a functioning procedure for gas chromatography/mass spectrometry (GC/MS) determination of N-terminal alkylvalines in hemoglobin were worked out. Derivatizing the protein in formamide solution with pentafluorophenyl isothiocyanate, using a /sup 2/H-alkylated protein as internal standard, and applying on-column injection during analysis, permit reproducible determination of hydroxyethylvaline and other adducts down into the dose range where cancer risks may be considered acceptably low.

  7. High Presence of Extracellular Hemoglobin in the Periventricular White Matter Following Preterm Intraventricular Hemorrhage.

    PubMed

    Ley, David; Romantsik, Olga; Vallius, Suvi; Sveinsdóttir, Kristbjörg; Sveinsdóttir, Snjolaug; Agyemang, Alex A; Baumgarten, Maria; Mörgelin, Matthias; Lutay, Nataliya; Bruschettini, Matteo; Holmqvist, Bo; Gram, Magnus

    2016-01-01

    Severe cerebral intraventricular hemorrhage (IVH) in preterm infants continues to be a major clinical problem, occurring in about 15-20% of very preterm infants. In contrast to other brain lesions the incidence of IVH has not been reduced over the last decade, but actually slightly increased. Currently over 50% of surviving infants develop post-hemorrhagic ventricular dilatation and about 35% develop severe neurological impairment, mainly cerebral palsy and intellectual disability. To date there is no therapy available to prevent infants from developing either hydrocephalus or serious neurological disability. It is known that blood rapidly accumulates within the ventricles following IVH and this leads to disruption of normal anatomy and increased local pressure. However, the molecular mechanisms causing brain injury following IVH are incompletely understood. We propose that extracellular hemoglobin is central in the pathophysiology of periventricular white matter damage following IVH. Using a preterm rabbit pup model of IVH the distribution of extracellular hemoglobin was characterized at 72 h following hemorrhage. Evaluation of histology, histochemistry, hemoglobin immunolabeling and scanning electron microscopy revealed presence of extensive amounts of extracellular hemoglobin, i.e., not retained within erythrocytes, in the periventricular white matter, widely distributed throughout the brain. Furthermore, double immunolabeling together with the migration and differentiation markers polysialic acid neural cell adhesion molecule (PSA-NCAM) demonstrates that a significant proportion of the extracellular hemoglobin is distributed in areas of the periventricular white matter with high extracellular plasticity. In conclusion, these findings support that extracellular hemoglobin may contribute to the pathophysiological processes that cause irreversible damage to the immature brain following IVH. PMID:27536248

  8. Inhibitory potential of pure isoflavonoids, red clover, and alfalfa extracts on hemoglobin glycosylation

    PubMed Central

    Hosseini, Mohsen; Asgary, Sedigheh; Najafi, Somayeh

    2015-01-01

    BACKGROUND Non-enzymatic glycosylation of hemoglobin is complications of diabetes. Antioxidant system imbalance can result in the emergence of free radicals’ destructive effects in the long-term. Red clover (Trifolium pratense L.) and alfalfa (Medicago sativa L.) contain isoflavonoids and have antioxidant activity. This experimental study evaluated the inhibitory activity of pure isoflavonoids (daidzein and genistein), red clover and alfalfa extracts on hemoglobin glycosylation. METHODS This study was performed in Iran. Stock solution of hydroalcoholic extracts of red clover and alfalfa in concentrations of 1 and 10 g/100 ml and stock solution of daidzein and genistein in concentrations of 250 ng, 500 ng, 25 µg and 250 µg/100 ml were prepared as case groups. Control group was without hydroalcoholic extracts of plants and pure isoflavonoids. All experiments were performed in triplicate. Hemoglobin was prepared and antioxidant activities were investigated to estimate degree of nonenzymatic hemoglobin glycosylation. RESULTS There was no significantly difference between used extracts (extract of red clover and alfalfa) and control of the hemoglobin glycosylation but using daidzein (P = 0.046, 0.029 and 0.021, respectively) and genistein (P = 0.034, 0.036 and 0.028) significantly inhibited (P < 0.050) this reaction in 25 µg/100 ml, 250 and 500 ng/100 ml concentrations when compared to control. in 25 µg/100 ml, 250 ng and 500 ng/100 ml concentrations percentage of inhibition were 32, 80 and 74.5% respectively with used of daidzein and were 21, 83 and 76% respectively with consumption of genistein. CONCLUSION According to decrease of glycation of hemoglobin with isoflavonoids, two used plant in this study containing isoflavonoid may be useful on diabetes. PMID:26405442

  9. Hemoglobin Targets and Blood Transfusions in Hemodialysis Patients without Symptomatic Cardiac Disease Receiving Erythropoietin Therapy

    PubMed Central

    Foley, Robert N.; Curtis, Bryan M.; Parfrey, Patrick S.

    2008-01-01

    Background and objectives: Optimal hemoglobin targets for chronic kidney disease patients receiving erythropoiesis-stimulating agents remain controversial. The effects of different hemoglobin targets on blood transfusion requirements have not been well characterized, despite their relevance to clinical decision-making. Design, setting, participants, & measurements: Five hundred ninety-six incident hemodialysis patients without symptomatic cardiac disease were randomly assigned to hemoglobin targets of 9.5 to 11.5 g/dl or 13.5 to 14.5 g/dl for 96 wk using epoetin alfa as primary therapy and changes in left ventricular structure as the primary outcome (previously reported). Patients were masked to treatment assignment. Blood transfusion data were prospectively collected at 4-wk intervals. Results: The mean age and prior duration of dialysis therapy of the study population were 50.8 and 0.8 yr, respectively. Previously reported mortality was similar in low and high-target subjects, at 4.7 (95% confidence interval 3.0, 7.3) and 3.1 (1.8, 5.4) per hundred patient years, respectively. Transfusion rates were 0.66 (0.59, 0.74) units of blood per year in low and 0.26 (0.22, 0.32) in high-target subjects (P < 0.0001). Hemoglobin level at transfusion (7.7 [7.5, 7.9]) versus 8.1 [7.6, 8.5] g/dl) were similar with both groups. High hemoglobin target was a significant predictor of time to first transfusion independent of baseline associations (hazard ratio = 0.42; 95% confidence interval = 0.26 − 0.67). Conclusions: In hemodialysis patients with comparatively low mortality risks, normal hemoglobin targets may reduce the need for transfusions. PMID:18922988

  10. High Presence of Extracellular Hemoglobin in the Periventricular White Matter Following Preterm Intraventricular Hemorrhage

    PubMed Central

    Ley, David; Romantsik, Olga; Vallius, Suvi; Sveinsdóttir, Kristbjörg; Sveinsdóttir, Snjolaug; Agyemang, Alex A.; Baumgarten, Maria; Mörgelin, Matthias; Lutay, Nataliya; Bruschettini, Matteo; Holmqvist, Bo; Gram, Magnus

    2016-01-01

    Severe cerebral intraventricular hemorrhage (IVH) in preterm infants continues to be a major clinical problem, occurring in about 15–20% of very preterm infants. In contrast to other brain lesions the incidence of IVH has not been reduced over the last decade, but actually slightly increased. Currently over 50% of surviving infants develop post-hemorrhagic ventricular dilatation and about 35% develop severe neurological impairment, mainly cerebral palsy and intellectual disability. To date there is no therapy available to prevent infants from developing either hydrocephalus or serious neurological disability. It is known that blood rapidly accumulates within the ventricles following IVH and this leads to disruption of normal anatomy and increased local pressure. However, the molecular mechanisms causing brain injury following IVH are incompletely understood. We propose that extracellular hemoglobin is central in the pathophysiology of periventricular white matter damage following IVH. Using a preterm rabbit pup model of IVH the distribution of extracellular hemoglobin was characterized at 72 h following hemorrhage. Evaluation of histology, histochemistry, hemoglobin immunolabeling and scanning electron microscopy revealed presence of extensive amounts of extracellular hemoglobin, i.e., not retained within erythrocytes, in the periventricular white matter, widely distributed throughout the brain. Furthermore, double immunolabeling together with the migration and differentiation markers polysialic acid neural cell adhesion molecule (PSA-NCAM) demonstrates that a significant proportion of the extracellular hemoglobin is distributed in areas of the periventricular white matter with high extracellular plasticity. In conclusion, these findings support that extracellular hemoglobin may contribute to the pathophysiological processes that cause irreversible damage to the immature brain following IVH. PMID:27536248

  11. Cross-sectional and longitudinal association between hemoglobin concentration and hypertension

    PubMed Central

    Kim, Na Hyun; Lee, Ju-Mi; Kim, Hyeon Chang; Lee, Joo-Young; Yeom, Hyungseon; Lee, Jung Hyun; Suh, Il

    2016-01-01

    Abstract We investigated the cross-sectional and longitudinal associations between hemoglobin concentration and hypertension in a Korean population. Between 2006 and 2013, we examined 4899 participants with mean age of 56.6 years (range 35–88 years) from a rural community. We excluded 298 participants with a history of myocardial infarction or stroke and 264 participants with very low hemoglobin levels (men: <13.3 g/dL; women: <11.6 g/dL). Finally, we performed a cross-sectional analysis on 1629 men and 2708 women. Longitudinal associations were evaluated in 654 men and 1099 women, after excluding 2584 people with hypertension at baseline and those who did not participate in follow-up examinations. Hypertension was defined as systolic blood pressure ≥140 mm Hg, diastolic blood pressure ≥90 mm Hg, or use of antihypertensive treatment. The mean hemoglobin level was significantly higher in people with hypertension than in those without hypertension (P = 0.002 for men, P = 0.006 for women). On cross-sectional analysis, the odds ratio (95% confidence interval) for hypertension per 1 standard deviation increase in hemoglobin concentration (1.2 g/dL) was 1.11 (1.05–1.18) before adjustment and 1.20 (1.09–1.32) after adjusting for age, sex, body mass index, kidney markers, lifestyle factors, and comorbidities. On longitudinal analysis, the relative risk (95% confidence interval) for incident hypertension per 1 standard deviation increase in hemoglobin concentration was 1.09 (0.96–1.23) before adjustment and 0.91 (0.78–1.08) after adjusting for age, sex, body mass index, lifestyle factors, baseline blood pressure, baseline comorbidities, and baseline kidney markers. This study suggests that hemoglobin per se does not cause hypertension development. PMID:27741113

  12. Adult, embryonic and fetal hemoglobin are expressed in human glioblastoma cells.

    PubMed

    Emara, Marwan; Turner, A Robert; Allalunis-Turner, Joan

    2014-02-01

    Hemoglobin is a hemoprotein, produced mainly in erythrocytes circulating in the blood. However, non-erythroid hemoglobins have been previously reported in other cell types including human and rodent neurons of embryonic and adult brain, but not astrocytes and oligodendrocytes. Human glioblastoma multiforme (GBM) is the most aggressive tumor among gliomas. However, despite extensive basic and clinical research studies on GBM cells, little is known about glial defence mechanisms that allow these cells to survive and resist various types of treatment. We have shown previously that the newest members of vertebrate globin family, neuroglobin (Ngb) and cytoglobin (Cygb), are expressed in human GBM cells. In this study, we sought to determine whether hemoglobin is also expressed in GBM cells. Conventional RT-PCR, DNA sequencing, western blot analysis, mass spectrometry and fluorescence microscopy were used to investigate globin expression in GBM cell lines (M006x, M059J, M059K, M010b, U87R and U87T) that have unique characteristics in terms of tumor invasion and response to radiotherapy and hypoxia. The data showed that α, β, γ, δ, ζ and ε globins are expressed in all tested GBM cell lines. To our knowledge, we are the first to report expression of fetal, embryonic and adult hemoglobin in GBM cells under normal physiological conditions that may suggest an undefined function of those expressed hemoglobins. Together with our previous reports on globins (Ngb and Cygb) expression in GBM cells, the expression of different hemoglobins may constitute a part of series of active defence mechanisms supporting these cells to resist various types of treatments including chemotherapy and radiotherapy.

  13. Tyrosine residues as redox cofactors in human hemoglobin: implications for engineering nontoxic blood substitutes.

    PubMed

    Reeder, Brandon J; Grey, Marie; Silaghi-Dumitrescu, Radu-Lucian; Svistunenko, Dimitri A; Bülow, Leif; Cooper, Chris E; Wilson, Michael T

    2008-11-01

    Respiratory proteins such as myoglobin and hemoglobin can, under oxidative conditions, form ferryl heme iron and protein-based free radicals. Ferryl myoglobin can safely be returned to the ferric oxidation state by electron donation from exogenous reductants via a mechanism that involves two distinct pathways. In addition to direct transfer between the electron donor and ferryl heme edge, there is a second pathway that involves "through-protein" electron transfer via a tyrosine residue (tyrosine 103, sperm whale myoglobin). Here we show that the heterogeneous subunits of human hemoglobin, the alpha and beta chains, display significantly different kinetics for ferryl reduction by exogenous reductants. By using selected hemoglobin mutants, we show that the alpha chain possesses two electron transfer pathways, similar to myoglobin. Furthermore, tyrosine 42 is shown to be a critical component of the high affinity, through-protein electron transfer pathway. We also show that the beta chain of hemoglobin, lacking the homologous tyrosine, does not possess this through-protein electron transfer pathway. However, such a pathway can be engineered into the protein by mutation of a specific phenylalanine residue to a tyrosine. High affinity through-protein electron transfer pathways, whether native or engineered, enhance the kinetics of ferryl removal by reductants, particularly at low reductant concentrations. Ferryl iron has been suggested to be a major cause of the oxidative toxicity of hemoglobin-based blood substitutes. Engineering hemoglobin with enhanced rates of ferryl removal, as we show here, is therefore likely to result in molecules better suited for in vivo oxygen delivery.

  14. Continuous and noninvasive hemoglobin monitoring reduces red blood cell transfusion during neurosurgery: a prospective cohort study.

    PubMed

    Awada, Wael N; Mohmoued, Maher F; Radwan, Tarek M; Hussien, Gomaa Z; Elkady, Hany W

    2015-12-01

    Continuous, noninvasive hemoglobin (SpHb) monitoring provides clinicians with the trending of changes in hemoglobin, which has the potential to alter red blood cell transfusion decision making. The objective of this study was to evaluate the impact of SpHb monitoring on blood transfusions in high blood loss surgery. In this prospective cohort study, eligible patients scheduled for neurosurgery were enrolled into either a Control Group or an intervention group (SpHb Group). The Control Group received intraoperative hemoglobin monitoring by intermittent blood sampling when there was an estimated 15% blood loss. If the laboratory value indicated a hemoglobin level of ≤10 g/dL, a red blood cell transfusion was started and continued until the estimated blood loss was replaced and a laboratory hemoglobin value was >l0 g/dL. In the SpHb Group patients were monitored with a Radical-7 Pulse CO-Oximeter for continuous noninvasive hemoglobin values. Transfusion was started when the SpHb value fell to ≤l0 g/dL and was continued until the SpHb was ≥l0 g/dL. Blood samples were taken pre and post transfusion. Percent of patients transfused, average amount of blood transfused in those who received transfusions and the delay time from the hemoglobin reading of <10 g/dL to the start of transfusion (transfusion delay) were compared between groups. The trending ability of SpHb, and the bias and precision of SpHb compared to the laboratory hemoglobin were calculated. Compared to the Control Group, the SpHb Group had fewer units of blood transfused (1.0 vs 1.9 units for all patients; p ≤ 0.001, and 2.3 vs 3.9 units in patients receiving transfusions; p ≤ 0.0 l), fewer patients receiving >3 units (32 vs 73%; p ≤ 0.01) and a shorter time to transfusion after the need was established (9.2 ± 1.7 vs 50.2 ± 7.9 min; p ≤ 0.00 l). The absolute accuracy of SpHb was 0.0 ± 0.8 g/dL and trend accuracy yielded a coefficient of determination of 0.93. Adding SpHb monitoring to

  15. Spin state transition in the active center of the hemoglobin molecule: DFT + DMFT study

    NASA Astrophysics Data System (ADS)

    Novoselov, D.; Korotin, Dm. M.; Anisimov, V. I.

    2016-05-01

    An ab initio study of electronic and spin configurations of the iron ion in the active center of the human hemoglobin molecule is presented. With a combination of the Density Functional Theory (DFT) method and the Dynamical Mean Field Theory (DMFT) approach, the spin state transition description in the iron ion during the oxidation process is significantly improved in comparison with previous attempts. It was found that the origin of the iron ion local moment behavior both for the high-spin and for the low-spin states in the hemoglobin molecule is caused by the presence of a mixture of several atomic states with comparable statistical probability.

  16. Hemoglobin istanbul: substitution of glutamine for histidine in a proximal histidine (F8(92)β)

    PubMed Central

    Aksoy, M.; Erdem, S.; Efremov, G. D.; Wilson, J. B.; Huisman, T. H. J.; Schroeder, W. A.; Shelton, J. R.; Shelton, J. B.; Ulitin, O. N.; Müftüoğlu, A.

    1972-01-01

    A presumably spontaneous mutation has resulted in the formation of Hemoglobin (Hb) Istanbul in which glutamine is substituted for histidine in the proximal position of the β-chain (F8(92)). The anemia and other physiological effects that occur in the presence of Hb Istanbul were much ameliorated by splenectomy. Hb Istanbul is a relatively unstable molecule which produces a rather moderate case of “unstable hemoglobin hemolytic anemia.” In the determination of structure, a method of preferential cleavage of an aspartyl-proline bond at residues 99-100 of the β-chain was used. Images PMID:4639022

  17. Prognostic Factors Affecting Locally Recurrent Rectal Cancer and Clinical Significance of Hemoglobin

    SciTech Connect

    Rades, Dirk Kuhn, Hildegard; Schultze, Juergen; Homann, Nils; Brandenburg, Bernd; Schulte, Rainer; Krull, Andreas; Schild, Steven E.; Dunst, Juergen

    2008-03-15

    Purpose: To investigate potential prognostic factors, including hemoglobin levels before and during radiotherapy, for associations with survival and local control in patients with unirradiated locally recurrent rectal cancer. Patients and Methods: Ten potential prognostic factors were investigated in 94 patients receiving radiotherapy for recurrent rectal cancer: age ({<=}68 vs. {>=}69 years), gender, Eastern Cooperative Oncology Group performance status (0-1 vs. 2-3), American Joint Committee on Cancer (AJCC) stage ({<=}II vs. III vs. IV), grading (G1-2 vs. G3), surgery, administration of chemotherapy, radiation dose (equivalent dose in 2-Gy fractions: {<=}50 vs. >50 Gy), and hemoglobin levels before (<12 vs. {>=}12 g/dL) and during (majority of levels: <12 vs. {>=}12 g/dL) radiotherapy. Multivariate analyses were performed, including hemoglobin levels, either before or during radiotherapy (not both) because these are confounding variables. Results: Improved survival was associated with better performance status (p < 0.001), lower AJCC stage (p = 0.023), surgery (p = 0.011), chemotherapy (p = 0.003), and hemoglobin levels {>=}12 g/dL both before (p = 0.031) and during (p < 0.001) radiotherapy. On multivariate analyses, performance status, AJCC stage, and hemoglobin levels during radiotherapy maintained significance. Improved local control was associated with better performance status (p = 0.040), lower AJCC stage (p = 0.010), lower grading (p = 0.012), surgery (p < 0.001), chemotherapy (p < 0.001), and hemoglobin levels {>=}12 g/dL before (p < 0.001) and during (p < 0.001) radiotherapy. On multivariate analyses, chemotherapy, grading, and hemoglobin levels before and during radiotherapy remained significant. Subgroup analyses of the patients having surgery demonstrated the extent of resection to be significantly associated with local control (p = 0.011) but not with survival (p = 0.45). Conclusion: Predictors for outcome in patients who received radiotherapy for

  18. Hemoglobin affinity and structure in high-altitude and sea-level carnivores from Peru.

    PubMed

    León-Velarde, F; de Muizon, C; Palacios, J A; Clark, D; Monge, C

    1996-04-01

    We compared hemoglobin affinity (P50) and structure of high altitude (HA) carnivores with populations of the same species or genus living at sea level (SL). P50 was measured in cats, pumas and foxes. It differed in animals occupying both niches. SL: cat 29.3 torr, puma 36.3 torr, fox 26.2 torr; HA: cat 22.5 torr, puma 31.1 torr, fox 18.5 torr. Heme and globins were fractionated by HPLC. Puma and fox hemoglobins also showed structural differences. P50 is lower in genotypically HA-adapted species studied and can differentiate SL and HA populations of the same species.

  19. Continuous and noninvasive hemoglobin monitoring reduces red blood cell transfusion during neurosurgery: a prospective cohort study.

    PubMed

    Awada, Wael N; Mohmoued, Maher F; Radwan, Tarek M; Hussien, Gomaa Z; Elkady, Hany W

    2015-12-01

    Continuous, noninvasive hemoglobin (SpHb) monitoring provides clinicians with the trending of changes in hemoglobin, which has the potential to alter red blood cell transfusion decision making. The objective of this study was to evaluate the impact of SpHb monitoring on blood transfusions in high blood loss surgery. In this prospective cohort study, eligible patients scheduled for neurosurgery were enrolled into either a Control Group or an intervention group (SpHb Group). The Control Group received intraoperative hemoglobin monitoring by intermittent blood sampling when there was an estimated 15% blood loss. If the laboratory value indicated a hemoglobin level of ≤10 g/dL, a red blood cell transfusion was started and continued until the estimated blood loss was replaced and a laboratory hemoglobin value was >l0 g/dL. In the SpHb Group patients were monitored with a Radical-7 Pulse CO-Oximeter for continuous noninvasive hemoglobin values. Transfusion was started when the SpHb value fell to ≤l0 g/dL and was continued until the SpHb was ≥l0 g/dL. Blood samples were taken pre and post transfusion. Percent of patients transfused, average amount of blood transfused in those who received transfusions and the delay time from the hemoglobin reading of <10 g/dL to the start of transfusion (transfusion delay) were compared between groups. The trending ability of SpHb, and the bias and precision of SpHb compared to the laboratory hemoglobin were calculated. Compared to the Control Group, the SpHb Group had fewer units of blood transfused (1.0 vs 1.9 units for all patients; p ≤ 0.001, and 2.3 vs 3.9 units in patients receiving transfusions; p ≤ 0.0 l), fewer patients receiving >3 units (32 vs 73%; p ≤ 0.01) and a shorter time to transfusion after the need was established (9.2 ± 1.7 vs 50.2 ± 7.9 min; p ≤ 0.00 l). The absolute accuracy of SpHb was 0.0 ± 0.8 g/dL and trend accuracy yielded a coefficient of determination of 0.93. Adding SpHb monitoring to

  20. Racial Contrasts in Hemoglobin Levels and Dietary Patterns Related to Hematopoiesis in Children: The Bogalusa Heart Study.

    ERIC Educational Resources Information Center

    Nicklas, Theresa A.; And Others

    1987-01-01

    Racial differences in hemoglobin were explored in pre-adolescent and adolescent children. After controlling for variations in dietary patterns, race accounted for a notable proportion of hemoglobin variance in both age groups. These differences exist independently of nutrient intake and maturational changes. (Author/VM)

  1. Functional and biochemical properties of the hemoglobins of the burrowing brittle star Hemipholis elongata say (Echinodermata, Ophiuroidea).

    PubMed

    Christensen, Ana Beardsley; Colacino, James M; Bonaventura, Celia

    2003-08-01

    The burrowing brittle star Hemipholis elongata (Say) possesses hemoglobin-containing coelomocytes (RBCs) in its water vascular system. The RBCs, which circulate between the arms and body, are thought to play a role in oxygen transport. The hemoglobin of adult animals has a moderate affinity for oxygen (P(50) = 11.4 mm Hg at pH 8, 20 degrees C, measured in cellulo) and exhibits cooperativity (Hill coefficient > 1.7). The hemoglobin of juveniles has a higher affinity (P(50) = 2.3 mmHg at pH 8.0, 20 degrees C) and also exhibits cooperativity. The oxygen-binding properties of the hemoglobin are relatively insensitive to pH, temperature, and hydrogen sulfide. Adult hemoglobin is a heterogeneous mixture composed of three major fractions. The combined results of electrospray mass spectrometry and oxygen-binding experiments performed on purified fractions indicate that the native hemoglobin is in the form of homopolymers. A partial amino acid sequence (about 40 amino acids) of adult hemoglobin reveals little homology with holothurian hemoglobins.

  2. Purification of Hemoglobin from Red Blood Cells using Tangential Flow Filtration and Immobilized Metal Ion Affinity Chromatography

    PubMed Central

    Elmer, Jacob; Harris, David; Palmer, Andre F.

    2011-01-01

    Two methods for purifying hemoglobin (Hb) from red blood cells (RBCs) are examined and compared. In the first method, red blood cell lysate is clarified with a 50 nm tangential flow filter and hemoglobin is purified using immobilized metal ion affinity chromatography (IMAC). In the second method, RBC lysate is processed with 50 nm, 500 kDa, and 50-100 kDa tangential flow filters, then hemoglobin is purified with IMAC. Our results show that the hemoglobins from both processes produce identical Hb products that are ultrapure and retain their biophysical properties (except for chicken hemoglobin, which shows erratic oxygen binding behavior after purification). Therefore, the most efficient method for Hb purification appears to be clarification with a 50 nm tangential flow filter, followed by purification with IMAC, and sample concentration/polishing on a 10-50 kDa tangential flow filter. PMID:21195679

  3. 21 CFR 864.8165 - Calibrator for hemoglobin or hematocrit measurement.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Calibrator for hemoglobin or hematocrit measurement. 864.8165 Section 864.8165 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Reagents §...

  4. 21 CFR 864.8165 - Calibrator for hemoglobin or hematocrit measurement.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Calibrator for hemoglobin or hematocrit measurement. 864.8165 Section 864.8165 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Reagents §...

  5. 21 CFR 864.8165 - Calibrator for hemoglobin or hematocrit measurement.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Calibrator for hemoglobin or hematocrit measurement. 864.8165 Section 864.8165 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Reagents §...

  6. 21 CFR 864.8165 - Calibrator for hemoglobin or hematocrit measurement.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Calibrator for hemoglobin or hematocrit measurement. 864.8165 Section 864.8165 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Reagents §...

  7. 21 CFR 864.8165 - Calibrator for hemoglobin or hematocrit measurement.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Calibrator for hemoglobin or hematocrit measurement. 864.8165 Section 864.8165 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Reagents §...

  8. Substitutions in woolly mammoth hemoglobin confer biochemical properties adaptive for cold tolerance.

    PubMed

    Campbell, Kevin L; Roberts, Jason E E; Watson, Laura N; Stetefeld, Jörg; Sloan, Angela M; Signore, Anthony V; Howatt, Jesse W; Tame, Jeremy R H; Rohland, Nadin; Shen, Tong-Jian; Austin, Jeremy J; Hofreiter, Michael; Ho, Chien; Weber, Roy E; Cooper, Alan

    2010-06-01

    We have genetically retrieved, resurrected and performed detailed structure-function analyses on authentic woolly mammoth hemoglobin to reveal for the first time both the evolutionary origins and the structural underpinnings of a key adaptive physiochemical trait in an extinct species. Hemoglobin binds and carries O(2); however, its ability to offload O(2) to respiring cells is hampered at low temperatures, as heme deoxygenation is inherently endothermic (that is, hemoglobin-O(2) affinity increases as temperature decreases). We identify amino acid substitutions with large phenotypic effect on the chimeric beta/delta-globin subunit of mammoth hemoglobin that provide a unique solution to this problem and thereby minimize energetically costly heat loss. This biochemical specialization may have been involved in the exploitation of high-latitude environments by this African-derived elephantid lineage during the Pleistocene period. This powerful new approach to directly analyze the genetic and structural basis of physiological adaptations in an extinct species adds an important new dimension to the study of natural selection.

  9. Electron self-exchange in hemoglobins revealed by deutero-hemin substitution.

    PubMed

    Athwal, Navjot Singh; Alagurajan, Jagannathan; Sturms, Ryan; Fulton, D Bruce; Andreotti, Amy H; Hargrove, Mark S

    2015-09-01

    Hemoglobins (phytoglobins) from rice plants (nsHb1) and from the cyanobacterium Synechocystis (PCC 6803) (SynHb) can reduce hydroxylamine with two electrons to form ammonium. The reaction requires intermolecular electron transfer between protein molecules, and rapid electron self-exchange might play a role in distinguishing these hemoglobins from others with slower reaction rates, such as myoglobin. A relatively rapid electron self-exchange rate constant has been measured for SynHb by NMR, but the rate constant for myoglobin is equivocal and a value for nsHb1 has not yet been measured. Here we report electron self-exchange rate constants for nsHb1 and Mb as a test of their role in hydroxylamine reduction. These proteins are not suitable for analysis by NMR ZZ exchange, so a method was developed that uses cross-reactions between each hemoglobin and its deutero-hemin substituted counterpart. The resulting electron transfer is between identical proteins with low driving forces and thus closely approximates true electron self-exchange. The reactions can be monitored spectrally due to the distinct spectra of the prosthetic groups, and from this electron self-exchange rate constants of 880 (SynHb), 2900 (nsHb1), and 0.05M(-1) s(-1) (Mb) have been measured for each hemoglobin. Calculations of cross-reactions using these values accurately predict hydroxylamine reduction rates for each protein, suggesting that electron self-exchange plays an important role in the reaction.

  10. Simultaneous imaging of blood flow and hemoglobin concentration change in skin tissue using NIR speckle patterns

    NASA Astrophysics Data System (ADS)

    Aizu, Yoshihisa; Hirata, Tatsuya; Maeda, Takaaki; Nishidate, Izumi; Yokoi, Naomichi

    2009-07-01

    We propose a method for imaging simultaneously blood flow and hemoglobin concentration change in skin tissue using speckle patterns acquired at two wavelengths of 780 and 830 nm. Experimental results demonstrate that the method is useful for time-varying analysis of blood circulation in human forearm skin tissue from one set of sequential speckle images.

  11. Substitutions in woolly mammoth hemoglobin confer biochemical properties adaptive for cold tolerance.

    PubMed

    Campbell, Kevin L; Roberts, Jason E E; Watson, Laura N; Stetefeld, Jörg; Sloan, Angela M; Signore, Anthony V; Howatt, Jesse W; Tame, Jeremy R H; Rohland, Nadin; Shen, Tong-Jian; Austin, Jeremy J; Hofreiter, Michael; Ho, Chien; Weber, Roy E; Cooper, Alan

    2010-06-01

    We have genetically retrieved, resurrected and performed detailed structure-function analyses on authentic woolly mammoth hemoglobin to reveal for the first time both the evolutionary origins and the structural underpinnings of a key adaptive physiochemical trait in an extinct species. Hemoglobin binds and carries O(2); however, its ability to offload O(2) to respiring cells is hampered at low temperatures, as heme deoxygenation is inherently endothermic (that is, hemoglobin-O(2) affinity increases as temperature decreases). We identify amino acid substitutions with large phenotypic effect on the chimeric beta/delta-globin subunit of mammoth hemoglobin that provide a unique solution to this problem and thereby minimize energetically costly heat loss. This biochemical specialization may have been involved in the exploitation of high-latitude environments by this African-derived elephantid lineage during the Pleistocene period. This powerful new approach to directly analyze the genetic and structural basis of physiological adaptations in an extinct species adds an important new dimension to the study of natural selection. PMID:20436470

  12. 76 FR 51041 - Hemoglobin Standards and Maintaining Adequate Iron Stores in Blood Donors; Public Workshop

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-17

    ... HUMAN SERVICES Food and Drug Administration Hemoglobin Standards and Maintaining Adequate Iron Stores in... Standards and Maintaining Adequate Iron Stores in Blood Donors.'' The purpose of this public workshop is to... donor safety and blood availability, and potential measures to maintain adequate iron stores in...

  13. FORMATION OF HEMOGLOBIN AND ALBUMIN ADDUCTS OF BENZENE OXIDE IN MOUSE, RAT, AND HUMAN BLOOD

    EPA Science Inventory

    Little is known about the formation and disposition of benzene oxide (BO), the initial metabolite arising from oxidation of benzene by cytochrome P450. In this study, reactions of BO with hemoglobin (Hb) and albumin (Alb) were investigated in blood from B6C3F1 mice, F344 rats, ...

  14. Modeling changes in the hemoglobin concentration of skin with total diffuse reflectance spectroscopy

    NASA Astrophysics Data System (ADS)

    Glennie, Diana L.; Hayward, Joseph E.; Farrell, Thomas J.

    2015-03-01

    The ability to monitor changes in the concentration of hemoglobin in the blood of the skin in real time is a key component to personalized patient care. Since hemoglobin has a unique absorption spectrum in the visible light range, diffuse reflectance spectroscopy is the most common approach. Although the collection of the diffuse reflectance spectrum with an integrating sphere (IS) has several calibration challenges, this collection method is sufficiently user-friendly that it may be worth overcoming the initial difficulty. Once the spectrum is obtained, it is commonly interpreted with a log-inverse-reflectance (LIR) or "absorbance" analysis that can only accurately monitor changes in the hemoglobin concentration when there are no changes to the nonhemoglobin chromophore concentrations which is not always the case. We address the difficulties associated with collection of the diffuse reflectance spectrum with an IS and propose a model capable of retrieving relative changes in hemoglobin concentration from the visible light spectrum. The model is capable of accounting for concentration changes in the nonhemoglobin chromophores and is first characterized with theoretical spectra and liquid phantoms. The model is then used in comparison with a common LIR analysis on temporal measurements from blanched and reddened human skin.

  15. Using the NCBI Genome Databases to Compare the Genes for Human & Chimpanzee Beta Hemoglobin

    ERIC Educational Resources Information Center

    Offner, Susan

    2010-01-01

    The beta hemoglobin protein is identical in humans and chimpanzees. In this tutorial, students see that even though the proteins are identical, the genes that code for them are not. There are many more differences in the introns than in the exons, which indicates that coding regions of DNA are more highly conserved than non-coding regions.

  16. THE OXYGEN EQUILIBRIUM OF THE HEMOGLOBIN OF THE EEL, ANGUILLA ROSTRATA

    PubMed Central

    Riggs, Austen

    1951-01-01

    Kawamoto had reported that eel hemoglobin has a hyperbolic oxygen equilibrium function, with n in the Hill equation equal to 1. On the basis of Kawamoto's data and with new measurements, it is shown that the equilibrium function is in fact S-shaped, as in most other vertebrates, and n in Hill's equation equals 1.8. PMID:14873919

  17. Adair-based hemoglobin equilibrium with oxygen, carbon dioxide and hydrogen ion activity.

    PubMed

    Mateják, Marek; Kulhánek, Tomáš; Matoušek, Stanislav

    2015-04-01

    As has been known for over a century, oxygen binding onto hemoglobin is influenced by the activity of hydrogen ions (H⁺), as well as the concentration of carbon dioxide (CO₂). As is also known, the binding of both CO₂and H⁺ on terminal valine-1 residues is competitive. One-parametric situations of these hemoglobin equilibria at specific levels of H⁺, O₂or CO₂are also well described. However, we think interpolating or extrapolating this knowledge into an 'empirical' function of three independent variables has not yet been completely satisfactory. We present a model that integrates three orthogonal views of hemoglobin oxygenation, titration, and carbamination at different temperatures. The model is based only on chemical principles, Adair's oxygenation steps and Van't Hoff equation of temperature dependences. Our model fits the measurements of the Haldane coefficient and CO₂hemoglobin saturation. It also fits the oxygen dissociation curve influenced by simultaneous changes in H⁺, CO₂and O₂, which makes it a strong candidate for integration into more complex models of blood acid-base with gas transport, where any combination of mentioned substances can appear. PMID:25594800

  18. Smartphone dongle for simultaneous measurement of hemoglobin concentration and detection of HIV antibodies.

    PubMed

    Guo, Tiffany; Patnaik, Ritish; Kuhlmann, Kevin; Rai, Alex J; Sia, Samuel K

    2015-09-01

    It is traditionally difficult to incorporate two classes of diagnostic tests into a single platform. In this work, we demonstrate a microfluidic-based smartphone dongle that simultaneously measures concentration of hemoglobin and detects HIV antibodies. Specifically, we demonstrate how a previously published immunoassay device, which measured optical density of silver precipitation on gold colloids, can be expanded to quantitatively measure hemoglobin concentration via a colorimetric assay. By lysing whole blood components with CHAPS detergent, we achieved highly reproducible measurement of hemoglobin concentration with the device. We tested this dual test on 38 patient samples from Columbia University Medical Center. Compared with the Hemocue Hb 201+ analyzer, hemoglobin concentrations from our device were accurate within 1.2 g dL(-1), while the HIV immunoassay (in the presence of CHAPS detergent) showed 95% sensitivity and 95% specificity, comparable to our previous studies. This work demonstrates the feasibility of integrating two classes of diagnostic tests (a colorimetric-based quantitative measurement and an immunoassay based on silver precipitation on gold colloids) into a low-cost, fast, and low-power dongle that works with smartphones, and creates a novel dual panel with clinical utility for antenatal-care settings.

  19. Identification of a Novel Class of Covalent Modifiers of Hemoglobin as Potential Antisickling Agents

    PubMed Central

    Omar, A. M.; Mahran, M. A.; Ghatge, M. S.; Chowdhury, N.; Bamane, F. H. A.; El-Araby, M. E.; Abdulmalik, O.; Safo, M. K.

    2015-01-01

    Aromatic aldehydes and ethacrynic acid (ECA) exhibit antipolymerization properties that are beneficial for sickle cell disease therapy. Based on ECA pharmacophore and its atomic interaction with hemoglobin, we designed and synthesized several compounds--designated as KAUS (imidazolylacryloyl derivatives)--that we hypothesized would bind covalently to βCys93 of hemoglobin and inhibit sickling. The compounds surprisingly showed weak allosteric and antisickling properties. X-ray studies of hemoglobin in complex with representative KAUS compounds revealed an unanticipated mode of Michael addition reaction between the β-unsaturated carbon and the N-terminal αVal1 nitrogen at the α-cleft of hemoglobin, with no observable interaction with βCys93. Interestingly, the compounds exhibited almost no reactivity with the free amino acids, L-Val, L-His and L-Lys, however showed some reactivity with both glutathione and L-Cys. Our findings provide a molecular level explanation to the compounds biological activities and an important framework for targeted modifications that would yield novel potent antisickling agents. PMID:25974708

  20. [Influence of mastication on the amount of hemoglobin in human brain tissue].

    PubMed

    Sasaki, A

    2001-03-01

    The purpose of this study was to investigate the influence of mastication on the amount of hemoglobin in human brain tissue. Nine healthy volunteers (6 males and 3 females) participated in this study. They underwent two tasks: 1) at rest, 2) gum-chewing. In seven of the nine (4 males and 3 females), experimental occlusal interference was applied to the first molar of the mandibule on the habitual masticatory side. They underwent the gum-chewing task. To evaluate the amount of hemoglobin, both the hemoglobin oxygenation state and blood volume during gum-chewing were measured in the frontal region, using near-infrared spectroscopy. The amount of total-hemoglobin (blood volume) and oxyhemoglobin of subjects significantly increased during gum-chewing (p < 0.01). When the subjects finished gum-chewing, both levels returned to the original levels. When experimental occlusal interference was imposed on the subject, the amount of them significantly decreased compared with subjects without experimental occlusal interference (p < 0.05). The results suggested that increases of cerebral blood flow in the frontal region were not due to the mandibular movement, and that human brain activity caused by mastication was not only in the cortical masticatory area but also in the frontal region.

  1. Adair-based hemoglobin equilibrium with oxygen, carbon dioxide and hydrogen ion activity.

    PubMed

    Mateják, Marek; Kulhánek, Tomáš; Matoušek, Stanislav

    2015-04-01

    As has been known for over a century, oxygen binding onto hemoglobin is influenced by the activity of hydrogen ions (H⁺), as well as the concentration of carbon dioxide (CO₂). As is also known, the binding of both CO₂and H⁺ on terminal valine-1 residues is competitive. One-parametric situations of these hemoglobin equilibria at specific levels of H⁺, O₂or CO₂are also well described. However, we think interpolating or extrapolating this knowledge into an 'empirical' function of three independent variables has not yet been completely satisfactory. We present a model that integrates three orthogonal views of hemoglobin oxygenation, titration, and carbamination at different temperatures. The model is based only on chemical principles, Adair's oxygenation steps and Van't Hoff equation of temperature dependences. Our model fits the measurements of the Haldane coefficient and CO₂hemoglobin saturation. It also fits the oxygen dissociation curve influenced by simultaneous changes in H⁺, CO₂and O₂, which makes it a strong candidate for integration into more complex models of blood acid-base with gas transport, where any combination of mentioned substances can appear.

  2. Modeling changes in the hemoglobin concentration of skin with total diffuse reflectance spectroscopy.

    PubMed

    Glennie, Diana L; Hayward, Joseph E; Farrell, Thomas J

    2015-03-01

    The ability to monitor changes in the concentration of hemoglobin in the blood of the skin in real time is a key component to personalized patient care. Since hemoglobin has a unique absorption spectrum in the visible light range, diffuse reflectance spectroscopy is the most common approach. Although the collection of the diffuse reflectance spectrum with an integrating sphere (IS) has several calibration challenges, this collection method is sufficiently user-friendly that it may be worth overcoming the initial difficulty. Once the spectrum is obtained, it is commonly interpreted with a log-inverse-reflectance (LIR) or “absorbance” analysis that can only accurately monitor changes in the hemoglobin concentration when there are no changes to the nonhemoglobin chromophore concentrations which is not always the case. We address the difficulties associated with collection of the diffuse reflectance spectrum with an IS and propose a model capable of retrieving relative changes in hemoglobin concentration from the visible light spectrum. The model is capable of accounting for concentration changes in the nonhemoglobin chromophores and is first characterized with theoretical spectra and liquid phantoms. The model is then used in comparison with a common LIR analysis on temporal measurements from blanched and reddened human skin.

  3. Delay time of hemoglobin S polymerization prevents most cells from sickling in vivo

    SciTech Connect

    Mozzarelli, A.; Hofrichter, J.; Eaton, W.A.

    1987-07-31

    A laser photolysis technique has been developed to assess the quantitative significance of the delay time of hemoglobin S gelation to the pathophysiology of sickle cell disease. Changes in the saturation of hemoglobin S with carbon monoxide produced by varying the intensity of a photolytic laser beam were used to simulate changes in the saturation of oxyhemoglobin S produced by variations in oxygen pressure. The presence of polymer at steady-state saturation with carbon monoxide was determined by measurement of the kinetics of gelation after complete photodissociation. The kinetics are a very sensitive probe for polymer since small amounts of polymerized hemoglobin increase the rate of nucleation sufficiently to eliminate the delay period. First, the equilibrium gelation properties of partially photodissociated carbonmonoxyhemoglobin S were shown to be the same as partially oxygenated hemoglobin S, and the method was then used to determine the effect of saturation on the formation and disappearance of polymers in individual sickle cells. The saturation at which polymers first formed upon deoxygenation was much lower than the saturation at which polymers disappeared upon reoxygenation. The results indicate that at venous saturations with oxygen, gelation takes place in most cells at equilibrium, but is prevented from occurring in vivo because the delay times are sufficiently long that most cells return to the lungs and are reoxygenated before polymerization has begun.

  4. Genetics of Hemoglobin in the Deer Mouse, PEROMYSCUS MANICULATUS . II. Multiple Alleles at Regulatory Loci

    PubMed Central

    Snyder, Lee R. G.

    1978-01-01

    Deer mice are polymorphic for electrophoretic hemoglobin phenotypes showing one, two, or three bands. Within the multibanded phenotypes, there is considerable variation in the hemoglobin partitioning, defined as the fraction of total hemoglobin made up by the secondary and tertiary bands. In subspecies sonoriensis, for example, hemoglobin partitionings range from 0.03 to 0.38. The inheritance of partitioning values is under remarkably strict genetic control. The genetic variation is additive and the narrow heritability is close to 1.0. The inheritance data can be modeled in precise detail by postulating multiple-allele polymorphisms at globin regulatory loci. Comparison of simulated versus actual inheritance data demonstrates that the so-called null structural alleles actually produce functional globins.—The genetic controls in Peromyscus may be analogous to those in primates. Unfortunately, the molecular mechanisms effecting the regulation are unknown. Different subspecies of P. maniculatus show strikingly different arrays of partitioning values, but the role of natural selection in maintaining the quantitative polymorphisms remains obscure. PMID:669256

  5. Molecular oxygen migration through the xenon docking sites of human hemoglobin in the R-state.

    PubMed

    Lepeshkevich, Sergei V; Gilevich, Syargey N; Parkhats, Marina V; Dzhagarov, Boris M

    2016-09-01

    A nanosecond laser flash-photolysis technique was used to study bimolecular and geminate molecular oxygen (O2) rebinding to tetrameric human hemoglobin and its isolated α and β chains in buffer solutions equilibrated with 1atm of air and up to 25atm of xenon. Xenon binding to the isolated α chains and to the α subunits within tetrameric hemoglobin was found to cause a decrease in the efficiency of O2 escape by a factor of ~1.30 and 3.3, respectively. A kinetic model for O2 dissociation, rebinding, and migration through two alternative pathways in the hemoglobin subunits was introduced and discussed. It was shown that, in the isolated α chains and α subunits within tetrameric hemoglobin, nearly one- and two-third escaping molecules of O2 leave the protein via xenon docking sites, respectively. The present experimental data support the idea that O2 molecule escapes from the β subunits mainly through the His(E7) gate, and show unambiguously that, in the α subunits, in addition to the direct E7 channel, there is at least one alternative escape route leading to the exterior via the xenon docking sites. PMID:27288155

  6. FORMATION OF NITRO MUSK ADDUCTS OF RAINBOW TROUT HEMOGLOBIN FOR POTENTIAL USE AS BIOMARKERS OF EXPOSURE

    EPA Science Inventory

    The high use of nitro musk xylene (MX) and musk ketone (MK) as fragrances, and their persistence and bioaccumulation potential make them ubiquitous environmental contaminants. The 4-amino-MX (AMX) and 2-amino-MK (AMK) metabolites have been detected in trout fish hemoglobin (Hb) s...

  7. In vitro study of the direct effect of extracellular hemoglobin on myelin components.

    PubMed

    Bamm, Vladimir V; Lanthier, Danielle K; Stephenson, Erin L; Smith, Graham S T; Harauz, George

    2015-01-01

    There is a relationship between cerebral vasculature and multiple sclerosis (MS) lesions: abnormal accumulations of iron have been found in the walls of dilated veins in MS plaques. The sources of this iron can be varied, but capillary and venous hemorrhages leading to blood extravasation have been recorded, and could result in the release of hemoglobin extracellularly. Extracellular hemoglobin oxidizes quickly and is known to become a reactive molecule that triggers low-density lipoprotein oxidation and plays a pivotal role in atherogenesis. In MS, it could lead to local oxidative stress, inflammation, and tissue damage. Here, we investigated whether extracellular hemoglobin and its breakdown products can cause direct oxidative damage to myelin components in a peroxidative environment such as occurs in inflamed tissue. Oxidation of lipids was assessed by the formation of fluorescent peroxidized lipid-protein covalent adducts, by the increase in conjugated diene and malondialdehyde. Oxidation of proteins was analyzed by the change in protein mass. The results suggest that the globin radical could be a trigger of myelin basic protein oxidative cross-linking, and that heme transferred to the lipids is involved in lipid peroxidation. This study provides new insight into the mechanism by which hemoglobin exerts its pathological oxidative activity towards myelin components. This work supports further research into the vascular pathology in MS, to gain insight into the origin and role of iron deposits in disease pathogenesis, or in stimulation of different comorbidities such as cardiovascular disease.

  8. Challenges in HbA1c Analysis and Reporting in Patients with Variant Hemoglobins.

    PubMed

    Sultana, T A; Sheme, Z A; Sultana, G S; Sultana, B; Mishu, F A; Khan, N Z; Sarkar, B C; Muttalib, M A; Khan, S A; Choudhury, S; Mahtab, H

    2016-04-01

    Hemoglobin A1c (HbA(1)c) is a well-established indicator of mean glycemia. The presence of genetic variants of hemoglobin can profoundly affect the accuracy of HbA(1)c measurements. Variants of hemoglobin especially Hemoglobin E (HbE) is prevalent in South East Asia including Bangladesh. The objective of our study is to compare the HbA(1)c values measured on high performance liquid chromatography (HPLC) and Turbidimetric Inhibition Immunoassay (TINIA) in diabetic patients with variant hemoglobins including HbE. A total of 7595 diabetic patients receiving treatment at BIRDEM General Hospital were analyzed for HbA(1)c results within a period of two months from December 2013 to January 2014. Seventy two cases out of 7595 (0.95%) had either undetectable or below normal HbA(1)c levels (males-33 and females-39; ratio = 0.82:1) by HPLC method. In 34(0.45%) cases, HbA(1)c value was undetectable by HPLC method but was in the reportable range by TINIA method. In the other 38 (0.55%) cases, HbA(1)c levels were below the reportable range (<4%) by HPLC method but were in the normal or higher range by TINIA method. TINIA method did not agree with HPLC method on Bland Altman plot in the 38 cases with below normal HbA(1)c levels, [Mean bias -5.2(-9.3 to 1.0), 95% CI] but agreed very well [mean bias -0.21 (-0.84 to 0.42), y=1.1037+0.776X; r(2)=0.30, p<0.01] in controls. In control group mean MCV was 83.80±7.48 and in study group was 73.65±10.44. Alkaline electrophoresis confirmed the variant hemoglobin to be HbE. The fasting blood sugar levels of all the 72 cases correlated strongly with TINIA method (r(2) =0.75, p<0.0001) but not with HPLC (r = 0.24, p=0.13). In our regions where populations have a high prevalence of Hb variant, proper knowledge of hemoglobin variants which affect the measurements HbA(1)c level is essential. MCV of 80fl or below may serve as a rough guide to select samples that require analysis by TINIA method. Moreover, HPLC may be a convenient and inexpensive

  9. Effects of low doses of quercetin and genistein on oxidation and carbonylation in hemoglobin and myoglobin.

    PubMed

    Boadi, William Y; Johnson, Damitea

    2014-09-01

    Protein-bound carbonyls have been shown to increase with age as well as in numerous diseases including rheumatoid arthritis, adult respiratory syndrome pulmonary fibrosis, diabetes, Parkinson's disease, and Alzheimer's just to mention a few. The effects of the flavonoids quercetin and genistein were investigated according to their ability to inhibit the oxidation of hemoglobin and myoglobin via the Fenton's pathway. Antioxidative activity of the flavonoids were determined by oxidizing hemoglobin and myoglobin in separate experiments with 50 μM Fe(2+) and 0.01 mM hydrogen peroxide (H2O2) with and without quercetin and/or genistein. The samples were treated singly with either quercetin, genistein, or in combination at concentrations of 1.0, 1.5, 2.0, 2.5, 3.0, and 3.5 μM, respectively, dissolved in dimethyl sulfoxide (DMSO). Samples were then incubated in a water bath at 37°C for 8, 12, and 24 hr, respectively. Levels of carbonylation were assayed by the protein carbonyl assay and the carbonyl levels quantified and expressed per mg of protein. The results indicate that protein carbonyls for samples treated with quercetin or genistein decreased in a dose-dependent manner compared to the controls. That of quercetin compared to genistein was more efficient in reducing the levels of protein carbonylation in hemoglobin and myoglobin, respectively. The combination of both flavonoids did show a gradual decrease in carbonyl compounds for only hemoglobin for all the doses and times tested. The results indicate that both flavonoids at low doses inhibited carbonylation in both hemoglobin and myoglobin and the inhibition may be attributed to the prevention of protein oxidation. PMID:25026201

  10. The Folate-Vitamin B12 Interaction, Low Hemoglobin, and the Mortality Risk from Alzheimer's Disease.

    PubMed

    Min, Jin-Young; Min, Kyoung-Bok

    2016-03-21

    Abnormal hemoglobin levels are a risk factor for Alzheimer's disease (AD). Although the mechanism underlying these associations is elusive, inadequate micronutrients, particularly folate and vitamin B12, may increase the risk for anemia, cognitive impairment, and AD. In this study, we investigated whether the nutritional status of folate and vitamin B12 is involved in the association between low hemoglobin levels and the risk of AD mortality. Data were obtained from the 1999-2006 National Health and Nutrition Examination Survey (NHANES) and the NHANES (1999-2006) Linked Mortality File. A total of 4,688 participants aged ≥60 years with available baseline data were included in this study. We categorized three groups based on the quartiles of folate and vitamin B12 as follows: Group I (low folate and vitamin B12); Group II (high folate and low vitamin B12 or low folate and high vitamin B12); and Group III (high folate and vitamin B12). Of 4,688 participants, 49 subjects died due to AD. After adjusting for age, sex, ethnicity, education, smoking history, body mass index, the presence of diabetes or hypertension, and dietary intake of iron, significant increases in the AD mortality were observed in Quartile1 for hemoglobin (HR: 8.4, 95% CI: 1.4-50.8), and the overall risk of AD mortality was significantly reduced with increases in the quartile of hemoglobin (p for trend = 0.0200), in subjects with low levels of both folate and vitamin B12 at baseline. This association did not exist in subjects with at least one high level of folate and vitamin B12. Our finding shows the relationship between folate and vitamin B12 levels with respect to the association between hemoglobin levels and AD mortality. PMID:27003215

  11. Interpreting elevated fetal hemoglobin in pathology and health at the basic laboratory level: new and known γ- gene mutations associated with hereditary persistence of fetal hemoglobin.

    PubMed

    Amato, A; Cappabianca, M P; Perri, M; Zaghis, I; Grisanti, P; Ponzini, D; Di Biagio, P

    2014-02-01

    Fetal hemoglobin may be slightly or significantly elevated in post-natal life due to a number of causes. We report two novel mutations found on the promoter of the Aγ gene and summarize all common and rare determinants associated with hereditary persistence of fetal hemoglobin (HPFH) described thus far. Hematological and molecular analysis of the Aγ globin gene in two cases of HPFH. Comparison of the novel cases with all those described in the literature. We have found two novel mutations in three Italian patients with HbF values between 5.9% and 6.5% without an elevated HbA(2) and with normal hemoglobin parameters. In two probands (mother and son), a -197 C>T transition was observed, while in a single individual, a -113 A>G transition was present on the distal CCAAT box of the Aγ gene. As no other abnormalities were present in both γ-gene promoters and the changes are located on regulatory sequences, we may conclude that these mutations are responsible for the HPFH phenotype shown by the carriers. The laboratory should be able to discriminate between elevated HbF due to artifacts or to serious causes including bone marrow malignancies, aplastic anemia, and β-thalassemia major or recessive traits such as β-thalassemia minor, δβ-thalassemia, or nonpathological conditions induced by mutations or polymorphisms of the γ-gene promoters that may even be beneficial when present in patients with thalassemia major or sickle cell disease and, in particular, when these patients are treated with hydroxyurea.

  12. Sulfide binding is mediated by zinc ions discovered in the crystal structure of a hydrothermal vent tubeworm hemoglobin.

    PubMed

    Flores, Jason F; Fisher, Charles R; Carney, Susan L; Green, Brian N; Freytag, John K; Schaeffer, Stephen W; Royer, William E

    2005-02-22

    Key to the remarkable ability of vestimentiferan tubeworms to thrive in the harsh conditions of hydrothermal vents are hemoglobins that permit the sequestration and delivery of hydrogen sulfide and oxygen to chemoautotrophic bacteria. Here, we demonstrate that zinc ions, not free cysteine residues, bind sulfide in vestimentiferan hemoglobins. The crystal structure of the C1 hemoglobin from the hydrothermal vent tubeworm Riftia pachyptila has been determined to 3.15 A and revealed the unexpected presence of 12 tightly bound Zn(2+) ions near the threefold axes of this D(3) symmetric hollow sphere. Chelation experiments on R. pachyptila whole-coelomic fluid and purified hemoglobins reveal a role for Zn(2+) ions in sulfide binding. Free cysteine residues, previously proposed as sulfide-binding sites in vestimentiferan hemoglobins, are found buried in surprisingly hydrophobic pockets below the surface of the R. pachyptila C1 molecule, suggesting that access of these residues to environmental sulfide is restricted. Attempts to reduce the sulfide-binding capacities of R. pachyptila hemoglobins by addition of a thiol inhibitor were also unsuccessful. These findings challenge the currently accepted paradigm of annelid hemoglobin evolution and adaptation to reducing environments. PMID:15710902

  13. New method of tracing blood hemoglobin concentration to hematocrit ratio for monitoring plasma dilution and osmotic origin shifts in blood.

    PubMed

    Andrijauskas, Audrius; Ivaskevicius, Juozas

    2006-01-01

    Blood hemoglobin concentration and hematocrit are probably the most widely used parameters for outpatient and inpatient examination. In addition to their inherent significance for evaluation of blood viscosity and oxygen carrying capacity, these parameters are traditionally used as tracers of plasma dilution. Blood test derived results are conventionally recorded on multiple pages in patient's medical records making dynamical investigations tedious and time-consuming. In addition, research results describing plasma dilution by means of hemoglobin or hematocrit are presented in a clinically unpractical way. A new method, referred to as HBS Graphics (patent pending--USA serial # 60/712809) is introduced for the first time in this article. This method of evaluation of dynamical hemoglobin concentration, hematocrit and mean corpuscular hemoglobin concentration value deploys interfering parameter shifts for the evaluation of plasma dilution in relation to osmotic dynamics. The HBS Graphics complements two coordinate systems--hemoglobin concentration and hematocrit--with incorporated mean corpuscular hemoglobin concentration value specific trends referred to as radiating lines. Isosmotic plasma dilution and erythrocyte volume shifts follow radiating lines, while osmotic shifts induce intertrend shifts. This article also reviews other methods of tracing plasma dilution by means of blood hemoglobin concentration and hematocrit dynamics.

  14. Correlation of low levels of nitrite and high levels of fetal hemoglobin in patients with sickle cell disease at baseline

    PubMed Central

    Elias, Darcielle Bruna Dias; Rocha, Lilianne Brito da Silva; Cavalcante, Maritza Barbosa; Pedrosa, Alano Martins; Justino, Izabel Cristina Bandeira; Gonçalves, Romélia Pinheiro

    2012-01-01

    Background Sickle cell disease is a hemoglobinopathy characterized by hemolytic anemia, increased susceptibility to infections and recurrent vaso-occlusive crises that reduces the quality of life of sufferers. Objective To evaluate the correlation of the levels of lactate dehydrogenase, malonaldehyde and nitrite to fetal hemoglobin in patients with sickle cell disease not under treatment with hydroxyurea in outpatients at a university hospital in Fortaleza, Ceará, Brazil. Methods Forty-four patients diagnosed with sickle cell disease were enrolled at baseline. Diagnosis was confirmed by evaluating the beta globin gene using polymerase chain reaction-restriction fragment length polymorphism. The concentration of fetal hemoglobin was obtained by high-performance liquid chromatography. Serum levels of nitrite, malonaldehyde and lactate dehydrogenase were measured by biochemical methods. Results Significantly higher levels of lactate dehydrogenase, nitrite and malonaldehyde were observed in patients with sickle cell disease compared to a control group. The study of the correlation between fetal hemoglobin levels and these variables showed a negative correlation with nitrite levels. No correlation was found between fetal hemoglobin and malonaldehyde or lactate dehydrogenase. When the study population was stratified according to fetal hemoglobin levels, a decrease in the levels of nitrite was observed with higher levels of fetal hemoglobin (p-value = 0.0415). Conclusion The results show that, similar to fetal hemoglobin levels, the concentration of nitrite can predict the clinical course of the disease, but should not be used alone as a modulator of prognosis in patients with sickle cell disease. PMID:23049438

  15. Global allostery model of hemoglobin. Modulation of O(2) affinity, cooperativity, and Bohr effect by heterotropic allosteric effectors.

    PubMed

    Yonetani, Takashi; Park, Sung-Ick; Tsuneshige, Antonio; Imai, Kiyohiro; Kanaori, Kenji

    2002-09-13

    The O(2) equilibria of human adult hemoglobin have been measured in a wide range of solution conditions in the presence and absence of various allosteric effectors in order to determine how far hemoglobin can modulate its O(2) affinity. The O(2) affinity, cooperative behavior, and the Bohr effect of hemoglobin are modulated principally by tertiary structural changes, which are induced by its interactions with heterotropic allosteric effectors. In their absence, hemoglobin is a high affinity, moderately cooperative O(2) carrier of limited functional flexibility, the behaviors of which are regulated by the homotropic, O(2)-linked T/R quaternary structural transition of the Monod-Wyman-Changeux/Perutz model. However, the interactions with allosteric effectors provide such "inert" hemoglobin unprecedented magnitudes of functional diversities not only of physiological relevance but also of extreme nature, by which hemoglobin can behave energetically beyond what can be explained by the Monod-Wyman-Changeux/Perutz model. Thus, the heterotropic effector-linked tertiary structural changes rather than the homotropic ligation-linked T/R quaternary structural transition are energetically more significant and primarily responsible for modulation of functions of hemoglobin.

  16. Cloning of a DNA fragment encoding a heme-repressible hemoglobin-binding outer membrane protein from Haemophilus influenzae.

    PubMed Central

    Jin, H; Ren, Z; Pozsgay, J M; Elkins, C; Whitby, P W; Morton, D J; Stull, T L

    1996-01-01

    Haemophilus influenzae is able to use hemoglobin as a sole source of heme, and heme-repressible hemoglobin binding to the cell surface has been demonstrated. Using an affinity purification methodology, a hemoglobin-binding protein of approximately 120 kDa was isolated from H. influenzae type b strain HI689 grown in heme-restricted but not in heme-replete conditions. The isolated protein was subjected to N-terminal amino acid sequencing, and the derived amino acid sequence was used to design corresponding oligonucleotides. The oligonucleotides were used to probe a Southern blot of EcoRI-digested HI689 genomic DNA. A hybridizing band of approximately 4.2 kb was successfully cloned into pUC19. Using a 1.9-kb internal BglII fragment of the 4.2-kb clone as a probe, hybridization was seen in both typeable and nontypeable H. influenzae but not in other bacterial species tested. Following partial nucleotide sequencing of the 4.2-kb insert, a putative open reading frame was subcloned into an expression vector. The host Escherichia coli strain in which the cloned fragment was expressed bound biotinylated human hemoglobin, whereas binding of hemoglobin was not detected in E. coli with the vector alone. In conclusion, we hypothesize that the DNA fragment encoding an approximately 120-kDa heme-repressible hemoglobin-binding protein mediates one step in the acquisition of hemoglobin by H. influenzae in vivo. PMID:8757844

  17. Variant hemoglobin phenotypes may account for differential erythropoiesis-stimulating agent dosing in African-American hemodialysis patients.

    PubMed

    Derebail, Vimal K; Nachman, Patrick H; Key, Nigel S; Ansede, Heather; Falk, Ronald J; Rosamond, Wayne D; Kshirsagar, Abhijit V

    2011-11-01

    African-American patients with end-stage renal disease have historically lower hemoglobin concentrations and higher requirements of erythropoiesis-stimulating agent (ESA). While disparities in health-care access may partially explain these findings, the role of variant hemoglobin, such as sickle trait, has not been investigated. To clarify this, we evaluated 154 African-American patients receiving in-center hemodialysis with available hemoglobin phenotyping. The primary exposure was any abnormal hemoglobin variant and the primary outcome of higher-dose ESA was defined as a dose of 6500 or more units per treatment. Logistic regression assessed the association between variant hemoglobin and higher-dose ESA. Covariates included age, gender, diabetes, iron parameters, intravenous iron dose, parathyroid hormone, albumin, phosphorus, body mass index, vascular access type, hospitalization/missed treatments, smoking status, alcohol abuse, and gastrointestinal bleeding. Of 33 patients with variant hemoglobin, 24 had HbAS and 9 had HbAC. Univariate odds of higher-dose ESA among those with hemoglobin variants were twice that of those with the normal HbAA phenotype (odds ratio 2.05). In multivariate models, the likelihood of higher-dose ESA had an odds ratio of 3.31 and the nature of this relationship did not change in Poisson regression or sensitivity analyses. Hence, our findings may explain, in part, the difference in ESA dosing between Caucasians and African-Americans with end-stage renal disease but await further study.

  18. Cell signaling pathways involved in drug-mediated fetal hemoglobin induction: Strategies to treat sickle cell disease

    PubMed Central

    Liu, Li; Li, Biaoru; Makala, Levi H

    2015-01-01

    The developmental regulation of globin gene expression has shaped research efforts to establish therapeutic modalities for individuals affected with sickle cell disease and β-thalassemia. Fetal hemoglobin has been shown to block sickle hemoglobin S polymerization to improve symptoms of sickle cell disease; moreover, fetal hemoglobin functions to replace inadequate hemoglobin A synthesis in β-thalassemia thus serving as an effective therapeutic target. In the perinatal period, fetal hemoglobin is synthesized at high levels followed by a decline to adult levels by one year of age. It is known that naturally occurring mutations in the γ-globin gene promoters and distant cis-acting transcription factors produce persistent fetal hemoglobin synthesis after birth to ameliorate clinical symptoms. Major repressor proteins that silence γ-globin during development have been targeted for gene therapy in β-hemoglobinopathies patients. In parallel effort, several classes of pharmacological agents that induce fetal hemoglobin expression through molecular and cell signaling mechanisms have been identified. Herein, we reviewed the progress made in the discovery of signaling molecules targeted by pharmacologic agents that enhance γ-globin expression and have the potential for future drug development to treat the β-hemoglobinopathies. PMID:26283707

  19. Structure and oxygen equilibrium of the three coelomic cell hemoglobins of the echiuran worm Thalassema mellita (Conn).

    PubMed

    Vinson, C R; Bonaventura, J

    1987-01-01

    1. The three coelomic cell hemoglobins from Thalassema mellita have been isolated to purity; the two major components have dimeric structure while the third minor component has monomeric structure. 2. Acid-urea Triton gel electrophoresis of the isolated hemoglobins identified three polypeptides among the three hemoglobins, one of the dimeric hemoglobins is a heterodimer (pI = 4.9) with one polypeptide sharing identity with the monomeric hemoglobin (pI = 6.3), while the other dimer is a homodimer (pI = 4.5) consisting of the third polypeptide. 3. SDS gel electrophoresis suggests that the two dimeric hemoglobins have interpolypeptide disulfide bonds. 4. Coelomic cell suspensions and lysed coelomic cells have PO2 at half saturation (P50) of 2.5-3.0 mmHg and cooperativity values (n) of 1.5-1.93. 5. All three isolated hemoglobins have higher oxygen affinities and lower cooperativity values (P50 = 1-2 mmHg, n = 1-1.3) than lysed coelomic cells suggesting some heterotrophic and homotrophic interactions. PMID:3621904

  20. Hemoglobin Concentration and Cognitive Impairment in the Renal REasons for Geographic And Racial Differences in Stroke (REGARDS) Study

    PubMed Central

    Wadley, Virginia G.; Newsome, Britt B.; Zakai, Neil A.; McClure, Leslie A.; Howard, George; Warnock, David G.; McClellan, William

    2010-01-01

    Background. There is growing interest in determining the degree of anemia, which is clinically significant. The goal of this study was to determine the association between hemoglobin concentration and cognitive impairment in a large sample of U.S. adults. Methods. We used cross-sectional data from 19,701 adults participating in the REasons for Geographic And Racial Differences in Stroke study. Cognitive impairment was defined as a score of 4 or less on the six-item screener. Hemoglobin was analyzed in 1 g/dL increments relative to the World Health Organization (WHO) threshold (<13 g/dL for men and <12 g/dL for women). Results. The mean hemoglobin concentration was 13.7 ± 1.5 g/dL. The prevalence of cognitive impairment increased from 4.3% among individuals with a hemoglobin >3 g/dL above the WHO threshold to 16.8% for those with a hemoglobin ≥2 g/dL below the WHO threshold. After adjustment for demographics, chronic health conditions, health status, and inflammation, the association between reduced hemoglobin and cognitive impairment was attenuated and no longer significant, including among those with hemoglobin ≥2 g/dL below the WHO threshold (odds ratio 1.39, 95% confidence interval = 0.94–2.04). A test for linear trend was of borderline significance (p value = .06). For 94% of the sample within 2 g/dL of the WHO threshold, there was no relationship between hemoglobin concentration and the odds of cognitive impairment. The associations did not differ by sex and race. Conclusions. Within a large sample of community-dwelling adults, there was no significant association between hemoglobin concentration and cognitive impairment after multivariable adjustment. PMID:20634281

  1. Naturally crystalline hemoglobin of the nematode Mermis nigrescens. An in situ microspectrophotometric study of chemical properties and dichroism.

    PubMed Central

    Burr, A H; Harosi, F I

    1985-01-01

    A dichroic microspectrophotometer was used to measure isotropic and dichroic absorbance spectra of this unique cytoplasmic hemoglobin and its derivatives. A perfusion slide enabled changing the media bathing the Mermis head. The native spectrum, which has an exceptionally low alpha-band extinction, was shown to be entirely due to oxyhemoglobin. The CO-hemoglobin spectrum is more typical, however, the alpha- and beta-bands are unusually closely spaced. A ferric hemochrome was formed on oxidation with ferricyanide or hydroxylamine and was readily converted to ferric hemoglobin cyanide on adding cyanide. Aquoferric hemoglobin and ferric hemoglobin fluoride were not easily formed. Deoxyhemoglobin, identified by its typical absorption spectrum, was formed only under the extremely low O2 pressures attainable in the presence of dithionite. A glucose oxidase, catalase solution deoxygenated hemoglobin in human erythrocytes but not in adjacent Mermis preparations. The affinity for O2 is much greater than for CO. Also, spectral evidence points to an oxyheme environment that is different than in vertebrate hemoglobin and myoglobin. The polarization ratio (PR) magnitude and the PR spectrum were unaffected by perfusion with high refractive index solvents; therefore, form dichroism due to the rodlike crystals is negligible. Maximum extinction is approximately perpendicular to the long axis of the microscopic crystals, which are oriented parallel to the body axis within the hypodermal cells. The PR spectra of the hemoglobin derivatives strongly resemble the corresponding spectra previously reported of single crystals made of horse hemoglobin, whale myoglobin, or Aplysia myoglobin and change appropriately when the ligand is changed. This confirms that the intracellular crystals of Mermis are of oxyhemoglobin. PMID:3986282

  2. Primary structure of the hemoglobins from Sphenodon (Sphenodon punctatus, Tuatara, Rynchocephalia). Evidence for the expression of alpha D-gene.

    PubMed

    Abbasi, A; Wells, R M; Brittain, T; Braunitzer, G

    1988-08-01

    Sphenodon is the sole representative of the "beakhead" reptiles which were widely distributed during the Triassic period before the spectacular rise of dinosaurs. Sphenodon punctatus is the only survivor ("living fossil") of this period. The morphological features of Sphenodon are remarkably conservative and differ little from reptiles living 200 million years ago. In the present paper the determination of the primary structure of the tetrameric hemoglobins is described: three components are identified: hemoglobin A' (alpha A2 beta II2), hemoglobin A (alpha A2 beta I2) and hemoglobin D (alpha D2 beta II2). The components were characterized electrophoretically, the four different peptide chains were characterized by Triton electrophoresis as well as by high-performance liquid chromatography. The hemoglobins and--under dissociating conditions--also the chains, were isolated on columns of cellulose ion exchangers. Sequence determination was carried out after cleavage of the individual chains with trypsin and after a specific chemical cleavage of the Asp-Pro bond. For sequence determination the film technique and gas-phase method were employed. The data are compared with the sequence of the human hemoglobin, and interpretations of the amino-acid sequences are given. Particularly notable is the evidence of hemoglobin D: this hemoglobin (alpha D2 beta II2) is found only in birds, and in two cases in turtles. However, this component is not found in other reptiles. The results make possible an interpretation of the relatively high oxygen affinity and explain the lack of cooperativity (myoglobin properties) of these tetrameric hemoglobins. PMID:3214555

  3. Primary structure of the hemoglobins from Sphenodon (Sphenodon punctatus, Tuatara, Rynchocephalia). Evidence for the expression of alpha D-gene.

    PubMed

    Abbasi, A; Wells, R M; Brittain, T; Braunitzer, G

    1988-08-01

    Sphenodon is the sole representative of the "beakhead" reptiles which were widely distributed during the Triassic period before the spectacular rise of dinosaurs. Sphenodon punctatus is the only survivor ("living fossil") of this period. The morphological features of Sphenodon are remarkably conservative and differ little from reptiles living 200 million years ago. In the present paper the determination of the primary structure of the tetrameric hemoglobins is described: three components are identified: hemoglobin A' (alpha A2 beta II2), hemoglobin A (alpha A2 beta I2) and hemoglobin D (alpha D2 beta II2). The components were characterized electrophoretically, the four different peptide chains were characterized by Triton electrophoresis as well as by high-performance liquid chromatography. The hemoglobins and--under dissociating conditions--also the chains, were isolated on columns of cellulose ion exchangers. Sequence determination was carried out after cleavage of the individual chains with trypsin and after a specific chemical cleavage of the Asp-Pro bond. For sequence determination the film technique and gas-phase method were employed. The data are compared with the sequence of the human hemoglobin, and interpretations of the amino-acid sequences are given. Particularly notable is the evidence of hemoglobin D: this hemoglobin (alpha D2 beta II2) is found only in birds, and in two cases in turtles. However, this component is not found in other reptiles. The results make possible an interpretation of the relatively high oxygen affinity and explain the lack of cooperativity (myoglobin properties) of these tetrameric hemoglobins.

  4. [Hospital-acquired anemia and decrease of hemoglobin levels in hospitalized patients].

    PubMed

    Gianserra, Carina V; Agüero, Andrés P; Chapelet, Adrián G; Paradiso, Bruno; Spanevello, Valeria A; Del Pino, María A

    2011-01-01

    It is common to observe the development of anemia in hospitalized patients, especially in critical cases. Few studies have evaluated its prevalence and associated factors in patients in the general ward. The purpose of this study is to determine the prevalence, characteristics and associated clinical factors of hospital-acquired anemia and the drop of hemoglobin concentration in hospitalized patients. This is a cross-sectional, prospective and descriptive study. A total of 192 consecutive in-patients in the general ward were studied. Associated risk factors to the drop in hemoglobin by ≥ 2g/dl were analyzed; 139 patients (72.4%) presented anemia; 89 of them (46.4%) had it at admission and 50 (26%) developed hospital-acquired anemia, 47 out of 192 showed a drop in hemoglobin ≥ 2 g/dl(24.48%). They also presented lower values of hematocrite and hemoglobin at discharge (p = 0.01), parenteral hydration at a higher volume (p = 0.01), and lengthier hospitalizations (p = 0.0001). In the univariate analysis, the following variables were statistically significant risk factors: leukocytosis ≥ 11000 mm3 (OR; IC95%: 2,02; 1.03-4; p = 0.01), hospitalization days ≥ 7 (OR; IC95%:3.39; 1.62-7.09; p = 0.0006), parenteral hydration ≥ 1500 ml/day (OR; IC95%: 2.47; 1.06-6.4; p = 0.01), central venous access (OR; IC95%:10.29; 1.75-108.07; p = 0.003) and hospital-acquired anemia (OR; IC95%: 7.06; 3.41-15.83; p = 0.00000004). In the multivariate analysis, the following variables were independent predictive factors of the hemoglobin decrease = 2 g/dl: leukocytosis ≥ 11000 mm3 (OR; IC95%: 2.45; 1.14-5,27; p = 0.02), hospitalization days ≥ 7 (OR; IC95%:5.15; 2.19-12.07; p = 0.0002), parenteral hydration ≥ 1500 ml/day (OR; IC95%: 2.95; 1.13-7.72; p = 0.02), central venous access (OR; IC95%:8.82; 1.37-56.82; p = 0.02). Hospital-acquired anemia has a high prevalence. Lengthier stays, presence of leukocytosis, parenteral hydration and central venous access placement are

  5. Hemoglobins from bacteria to man: evolution of different patterns of gene expression.

    PubMed

    Hardison, R

    1998-04-01

    The discovery of hemoglobins in virtually all kingdoms of organisms has shown (1) that the ancestral gene for hemoglobin is ancient, and (2) that hemoglobins can serve additional functions besides transport of oxygen between tissues, ranging from intracellular oxygen transport to catalysis of redox reactions. These different functions of the hemoglobins illustrate the acquisition of new roles by a pre-existing structural gene, which requires changes not only in the coding regions but also in the regulatory elements of the genes. The evolution of different regulated functions within an ancient gene family allows an examination of the types of biosequence data that are informative for various types of issues. Alignment of amino acid sequences is informative for the phylogenetic relationships among the hemoglobins in bacteria, fungi, protists, plants and animals. Although many of these diverse hemoglobins are induced by low oxygen concentrations, to date none of the molecular mechanisms for their hypoxic induction shows common regulatory proteins; hence, a search for matches in non-coding DNA sequences would not be expected to be fruitful. Indeed, alignments of non-coding DNA sequences do not reveal significant matches even between mammalian alpha- and beta-globin gene clusters, which diverged approximately 450 million years ago and are still expressed in a coordinated and balanced manner. They are in very different genomic contexts that show pronounced differences in regulatory mechanisms. The alpha-globin gene is in constitutively active chromatin and is encompassed by a CpG island, which is a dominant determinant of its regulation, whereas the beta-globin gene is in A+T-rich genomic DNA. Non-coding sequence matches are not seen between avian and mammalian beta-globin gene clusters, which diverged approximately 250 million years ago, despite the fact that regulation of both gene clusters requires tissue-specific activation of a chromatin domain regulated by a locus

  6. GENOME-WIDE ASSOCIATION ANALYSES BASED ON WHOLE-GENOME SEQUENCING IN SARDINIA PROVIDE INSIGHTS INTO REGULATION OF HEMOGLOBIN LEVELS

    PubMed Central

    Danjou, Fabrice; Zoledziewska, Magdalena; Sidore, Carlo; Steri, Maristella; Busonero, Fabio; Maschio, Andrea; Mulas, Antonella; Perseu, Lucia; Barella, Susanna; Porcu, Eleonora; Pistis, Giorgio; Pitzalis, Maristella; Pala, Mauro; Menzel, Stephan; Metrustry, Sarah; Spector, Timothy D.; Leoni, Lidia; Angius, Andrea; Uda, Manuela; Moi, Paolo; Thein, Swee Lay; Galanello, Renzo; Abecasis, Gonçalo R.; Schlessinger, David; Sanna, Serena; Cucca, Francesco

    2015-01-01

    We report GWAS results for the levels of A1, A2 and fetal hemoglobins, analyzed for the first time concurrently. Integrating high-density array genotyping and whole-genome sequencing in a large general population cohort from Sardinia, we detected 23 associations at 10 loci. Five are due to variants at previously undetected loci: MPHOSPH9, PLTP-PCIF1, FOG1, NFIX, and CCND3. Among those at known loci, 10 are new lead variants and 4 are novel independent signals. Half of all variants also showed pleiotropic associations with different hemoglobins, which further corroborated some of the detected associations and revealed features of coordinated hemoglobin species production. PMID:26366553

  7. Evidence that the low-affinity folate-binding protein in erythrocyte hemolysate is identical to hemoglobin

    SciTech Connect

    Hansen, S.I.; Holm, J.; Lyngbye, J.

    1981-07-01

    Gel filtration studies on erythrocyte hemolysate demonstrated the presence of a folate binding protein, apparently of the low-affinity type, that co-elutes with hemoglobin. Further, the folate binder eluted with a low salt concentration after DEAE-Sepharose CL-6B anion-exchange chromatography of erythrocyte hemolysate at pH 6.3. The chromatographic behavior of hemoglobin labeled with (3H)folate was so similar to that of the present binder as to suggest that the folate binder in erythrocytes is in fact hemoglobin.

  8. Towards hemerythrin-based blood substitutes: comparative performance to hemoglobin on human leukocytes and umbilical vein endothelial cells.

    PubMed

    Fischer-Fodor, Eva; Mot, Augustin; Deac, Florina; Arkosi, Mariann; Silaghi-Dumitrescu, Radu

    2011-06-01

    Hemerythrin is a dioxygen-carrying protein whose oxidative/nitrosative stress-related reactivity is lower than that of hemoglobin, which may warrant investigation of hemerythrin as raw material for artificial oxygen carriers ('blood substitutes'). We report here the first biological tests for hemerythrin and its chemical derivatives, comparing their performance with that of a representative competitor, glutaraldehyde-polymerized bovine hemoglobin. Hemerythrin (native or derivatized) exhibits a proliferative effect on human umbilical vein endothelial cell (HUVEC) cultures, as opposed to a slight inhibitory effect of hemoglobin. A similar positive effect is displayed on human lymphocytes by glutaraldehyde-polymerized hemerythrin, but not by native or polyethylene glycol-derivatized hemerythrin.

  9. Online Hemoglobin and Oxygen Saturation Sensing During Continuous Renal Replacement Therapy with Regional Citrate Anticoagulation.

    PubMed

    Yessayan, Lenar T; Yee, Jerry; Frinak, Stan; Szamosfalvi, Balazs

    2015-01-01

    Optical hemoglobin and oxygen saturation sensor (OHOS) monitor when used in combination with other hemodynamic tools may be useful for continuous hemodynamic monitoring during ultrafiltration. The stand-alone OHOS monitor can easily be deployed predialyzer into the extracorporeal circuit of continuous renal replacement therapy (CRRT) systems. To maximize the accuracy of the OHOS in 24 hr CRRT systems, clotting in the optical blood chamber and the presensor dilution incurred by replacement fluid should be minimized. Sustained low-efficiency dialysis (SLED) with regional citrate anticoagulation is a therapy that incorporates an OHOS and maintains the overall reliability of hemoglobin (Hb) and saturation sensing. The system operates at a blood flow rate of 60 ml/min and a fixed acid citrate infusion rate of 150 ml/hr. The presensor dilution incurred by concentrated citrate infusion would result in a minimal Hb dilution (<0.7 g/dl) while minimizing optical blood chamber clotting during 24 hr SLED.

  10. In vivo Photoacoustic Spectroscopic Imaging of Hemoglobin Derivatives in Thermally Damaged Tissue

    NASA Astrophysics Data System (ADS)

    Aizawa, Kazuya; Sato, Shunichi; Saitoh, Daizoh; Ashida, Hiroshi; Obara, Minoru

    2009-06-01

    Photoacoustic (PA) spectroscopic measurement was performed for thermally damaged skin in a rat in vivo to analyze hemoglobin derivatives in the tissue. We observed PA signals at around 500 and 633 nm, which are center wavelengths of methemoglobin (MetHb) absorption peaks, at depths corresponding the uppermost dermis (˜0.16 mm) and hair follicles (˜0.62 mm), indicating formation of MetHb in these tissue regions. By scanning a PA detector on the tissue, two-dimensional PA images (tomograms) were produced. Subtraction imaging technique was used for multispectral PA tomograms to analyze specific components of hemoglobin derivatives in the tissue, by which the contrast of oxyhemogobin (HbO2)-associated PA signal has been improved and the distribution of PA signal that seems to reflect the concentration of MetHb has been visualized.

  11. Probing the energetics of proteins through structural perturbation: sites of regulatory energy in human hemoglobin.

    PubMed Central

    Pettigrew, D W; Romeo, P H; Tsapis, A; Thillet, J; Smith, M L; Turner, B W; Ackers, G K

    1982-01-01

    The sites of energy transduction within the human hemoglobin molecule for the regulation of oxygen affinity have been determined by an extensive study of the molecule's energetic response to structural alteration at individual amino acid residues. For 22 mutant and chemically modified hemoglobins we have determined the total free energy used by the tetrameric molecule for alteration of oxygen affinity at the four binding steps. The results imply that the regulation of oxygen binding affinity is due to energy changes which are mostly localized at the alpha 1 beta 2 interface. They also indicate a high degree of "internal cooperativity" within this contact region--i.e., the structural perturbations at individual residue sites are energetically coupled. Cooperativity in ligand binding is thus a reflection of cooperativity at a deeper level--that of the protein-protein interactions within the alpha 1 beta 2 interfacial domain. Images PMID:6952235

  12. Hemoglobin fructation promotes heme degradation through the generation of endogenous reactive oxygen species

    NASA Astrophysics Data System (ADS)

    Goodarzi, M.; Moosavi-Movahedi, A. A.; Habibi-Rezaei, M.; Shourian, M.; Ghourchian, H.; Ahmad, F.; Farhadi, M.; Saboury, A. A.; Sheibani, N.

    2014-09-01

    Protein glycation is a cascade of nonenzymatic reactions between reducing sugars and amino groups of proteins. It is referred to as fructation when the reducing monosaccharide is fructose. Some potential mechanisms have been suggested for the generation of reactive oxygen species (ROS) by protein glycation reactions in the presence of glucose. In this state, glucose autoxidation, ketoamine, and oxidative advance glycation end products (AGEs) formation are considered as major sources of ROS and perhaps heme degradation during hemoglobin glycation. However, whether fructose mediated glycation produces ROS and heme degradation is unknown. Here we report that ROS (H2O2) production occurred during hemoglobin fructation in vitro using chemiluminescence methods. The enhanced heme exposure and degradation were determined using UV-Vis and fluorescence spectrophotometry. Following accumulation of ROS, heme degradation products were accumulated reaching a plateau along with the detected ROS. Thus, fructose may make a significant contribution to the production of ROS, glycation of proteins, and heme degradation during diabetes.

  13. Simulation of oxygen saturation of hemoglobin solution, RBC suspension and hemosome by a neural network system.

    PubMed

    Kan, P; Chen, W K; Lee, C J

    1996-03-01

    Hemoglobin-based artificial blood substitutes as oxygen carrier is advantageous over current plasma expander. In this study, oxygen saturation of hemoglobin solution, red blood cell suspension and artificial blood substitute under various conditions were measured by yeast-consuming-oxygen experiments instead of spectrophotometer. The empirical results were assigned into training feedforward back-propagation neural network system in order to simulate the oxygen saturation model modulated by those factors such as pH, [Cl-], [2,3-DPG], pO2 and pCO2. Consequently, this neural network is able to simulate accurately the oxygen saturation of Hb solution. The prediction of hemosome is not agreed well possible because of the resistance of transport of oxygen. However, the results showed neural net can offer a simple and convenient way in comparison with the conventional methods, especially in dealing with complex and ambiguous problem.

  14. The USA Multicenter Prehosptial Hemoglobin -based Oxygen Carrier Resuscitation Trial: Scientific Rationale, Study Design, and Results

    PubMed Central

    Moore, Ernest E.; Johnson, Jeffrey L.; Moore, Frederick A.; Moore, Hunter B.

    2013-01-01

    The current generation of blood substitutes tested in clinical trials are red blood cell (RBC) substitutes; that is, they are designed primarily to transport oxygen. The products now being used in advanced-phase clinical trials are derived from hemoglobin (Hb) and are thus often referred to as Hb-based oxygen carriers (HBOCs). The potential benefits of HBOCs are well known (Box 1). The objectives of this overview are to provide the scientific background and rationale for the study design of the USA Multi-center Prehospital HBOC Resuscitation Trial and to present the results and discuss clinical implications. Box 1Potential clinical benefits of hemoglobin-based oxygen carriers in trauma careAvailabilityAbundant supplyUniversally compatibleProlonged shelf-lifeStorage at room temperatureSafetyNo disease transmissionsNo antigenic reactionsNo immunologic effectsEfficacyEnhanced oxygen deliveryImproved rheologic properties PMID:19341912

  15. Production of methionine γ- lyase in recombinant Citrobacter freundii bearing the hemoglobin gene.

    PubMed

    Kahraman, Huseyin; Aytan, Emel; Kurt, Ash Giray

    2011-09-01

    The production of antileukemic enzyme methionine γ-lyase (MGL) in distinctly related bacteria, Citrobacter freundii and in their recombinants expressing the Vitresocilla hemoglobin (VHb) has been studied. This study concerns the potential of Citrobacter freundii expressing the Vitreoscilla hemoglobin gene (vgb) for the methionine γ- liyase production. Methionine γ- liyase production by Citrobacter freundii and its vgb(-) and vgb(+) bearing recombinant strain was studied in shake-flasks under 200 rpm agitation, culture medium and 30 °C in a time-course manner. The vgb(+) and especially the carbon type had a dramatic effect on methionine γ- liyase production. The vgb(+) strain of C. freundii had about 2-fold and 3.1-fold higher levels of MGL than the host and vgb(-) strain, respectively.

  16. Experiments on Hemoglobin in Single Crystals and Silica Gels Distinguish among Allosteric Models

    PubMed Central

    Henry, Eric R.; Mozzarelli, Andrea; Viappiani, Cristiano; Abbruzzetti, Stefania; Bettati, Stefano; Ronda, Luca; Bruno, Stefano; Eaton, William A.

    2015-01-01

    Trapping quaternary structures of hemoglobin in single crystals or by encapsulation in silica gels has provided a demanding set of data to test statistical mechanical models of allostery. In this work, we compare the results of those experiments with predictions of the four major allosteric models for hemoglobin: the quaternary two-state model of Monod, Wyman, and Changeux; the tertiary two-state model of Henry et al., which is the simplest extension of the Monod-Wyman-Changeux model to include pre-equilibria of tertiary as well as quaternary conformations; the structure-based model of Szabo and Karplus; and the modification of the latter model by Lee and Karplus. We show that only the tertiary two-state model can provide a near quantitative explanation of the single-crystal and gel experimental results. PMID:26038112

  17. Hemoglobin A1c Testing and Amputation Rates in Black, Hispanic, and White Medicare Patients

    PubMed Central

    Suckow, Bjoern D.; Newhall, Karina A.; Bekelis, Kimon; Faerber, Adrienne E.; Gottlieb, Daniel J.; Skinner, Jonathan S.; Stone, David H.; Goodney, Philip P.

    2016-01-01

    Background Major (above-knee or below-knee) amputation is a complication of diabetes and is seen more common among black and Hispanic patients. While amputation rates have declined for patients with diabetes in the last decade, it remains unknown if these improvements have equitably extended across racial groups and if measures of diabetic care, such as hemoglobin A1c testing, are associated with these improvements. We set out to characterize secular changes in amputation rates among black, Hispanic, and white patients, and to determine associations between hemoglobin A1c testing and amputation risk. Methods We identified 11,942,840 Medicare patients (55% female) with diabetes over the age of 65 years between 2002 and 2012 and followed them for a mean of 6.6 years. Of these, 86% were white, 11.5% were black, and 2.5% were Hispanic. We recorded the occurrence of major amputation and hemoglobin A1c testing during this time period and studied secular changes in amputation rate by race (black, Hispanic, and white). Finally, we examined associations between amputation risk and hemoglobin A1c testing. We measured both the presence of any testing and testing consistency using 3 categories: poor consistency (hemoglobin A1c testing in 0–50% of years), medium consistency (testing in 50–90% of years), and high consistency (testing in >90% of the years in the cohort). Results Between 2002 and 2012, the average major lower-extremity amputation rate in diabetic Medicare patients was 1.78 per 1,000 per year for black patients, 1.15 per 1,000 per year for Hispanic patients, and 0.56 per 1,000 per year for white patients (P < 0.001). Over the study period, the incidence of major amputation in Medicare patients with diabetes declined by 54%, from 1.15 per 1,000 in 2002 to 0.53 per 1,000 in 2012 (rate ratio = 0.53, 95% CI = 0.51–0.54). The reduction in amputation rate was similar across racial groups: 52% for black patients, 61% for Hispanic patients, and 55% for white patients

  18. Discovery of the magnetic behavior of hemoglobin: A beginning of bioinorganic chemistry

    PubMed Central

    Bren, Kara L.; Eisenberg, Richard; Gray, Harry B.

    2015-01-01

    Two articles published by Pauling and Coryell in PNAS nearly 80 years ago described in detail the magnetic properties of oxy- and deoxyhemoglobin, as well as those of closely related compounds containing hemes. Their measurements revealed a large difference in magnetism between oxygenated and deoxygenated forms of the protein and, along with consideration of the observed diamagnetism of the carbonmonoxy derivative, led to an electronic structural formulation of oxyhemoglobin. The key role of hemoglobin as the main oxygen carrier in mammalian blood had been established earlier, and its allosteric behavior had been described in the 1920s. The Pauling–Coryell articles on hemoglobin represent truly seminal contributions to the field of bioinorganic chemistry because they are the first to make connections between active site electronic structure and the function of a metalloprotein. PMID:26508205

  19. Nanomolar detection of methylparaben by a cost-effective hemoglobin-based biosensor.

    PubMed

    Hajian, A; Ghodsi, J; Afraz, A; Yurchenko, O; Urban, G

    2016-12-01

    This work describes the development of a new biosensor for methylparaben determination using electrocatalytic properties of hemoglobin in the presence of hydrogen peroxide. The voltammetric oxidation of methylparaben by the proposed biosensor in phosphate buffer (pH=7.0), a physiological pH, was studied and it was confirmed that methylparaben undergoes a one electron-one proton reaction in a diffusion-controlled process. The biosensor was fabricated by carbon paste electrode modified with hemoglobin and multiwalled carbon nanotube. Based on the excellent electrochemical properties of the modified electrode, a sensitive voltammetric method was used for determination of methylparaben within a linear range from 0.1 to 13μmolL(-1) and detection limit of 25nmolL(-1). The developed biosensor possessed accurate and rapid response to methylparaben and showed good sensitivity, stability, and repeatability. Finally, the applicability of the proposed biosensor was verified by methylparaben evaluation in various real samples. PMID:27612696

  20. Measurement of the refractive index of hemoglobin solutions for a continuous spectral region

    PubMed Central

    Wang, Jin; Deng, Zhichao; Wang, Xiaowan; Ye, Qing; Zhou, Wenyuan; Mei, Jianchun; Zhang, Chunping; Tian, Jianguo

    2015-01-01

    Determination of the refractive index of hemoglobin solutions over a wide wavelength range remains challenging. A famous detour approach is the Kramers-Kronig (KK) analysis which can resolve the real part of complex refractive index from the imaginary part. However, KK analysis is limited by the contradiction between the requirement of semi-infinite frequency range and limited measured range. In this paper, based on the Multi-curve fitting method (MFM), continuous refractive index dispersion (CRID) of oxygenated and deoxygenated hemoglobin solutions are measured using a homemade symmetrical arm-linked apparatus in the continuous wavelength range with spectral resolution of about 0.259nm. A novel method to obtain the CRID is proposed. PMID:26203379