PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “HEMOGLOBIN AND COMPOUNDS”

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

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

At least 523 records · Page 29Linked to original sources

Liposome-encapsulated hemoglobin as an artificial red blood cell: characterization and scale-up.

Encapsulation methods using high pressure extrusion and homogenization were developed which produce hemoglobin-containing liposomes, approximately one micron or less in diameter with an oxygen-carrying capacity of more than half that of red blood cells (RBCs). These methods were developed for scaling-up liposome-encapsulated hemoglobin (LEH) production. Previously, the lack of adequate scale-up methods has been a serious barrier to full scale efficacy and toxicity testing for all the researchers engaged in such investigations. The scale-up methods and characterization of the resulting LEH preparations are presented.

Blood Substitutes↗

Analysis of DNA and hemoglobin adducts and sister chromatid exchanges in a human population occupationally exposed to propylene oxide: a pilot study.

Propylene oxide (PO), a simple alkylating agent used in the chemical industry, is weakly genotoxic and induces nasal cavity tumors in rodents on inhalation at high air concentrations. DNA adducts, hemoglobin adducts, and sister chromatid exchanges (SCE) were analyzed as biomarkers of exposure in a group of eight PO-exposed workers and eight nonexposed subjects. 1-2-Hydroxypropyladenine (1-HP-adenine) in DNA of WBCs was analyzed using a hypersensitive (32)P-postlabeling assay. HP-valine in hemoglobin was measured using gas chromatography/tandem mass spectrometry. Air measurements indicated PO levels in the range of 1-7 ppm. All three biomarkers showed significantly increased levels in the exposed workers. 1-HP-adenine was recorded in seven of the exposed workers (mean 0.66 mol/10(9) mol nucleotides) but was not detected in any of the control subjects. HP-valine was found in all subjects (means of 2.7 and 0.006 pmol/mg globin in exposed workers and controls, respectively). The average frequencies of SCE were 3.7/cell in exposed workers and 2.0/cell in controls, respectively. DNA and hemoglobin adducts were correlated (r = 0.887), as well as DNA adducts and SCE (r = 0.792) and hemoglobin adducts and SCE (r = 0.762). The present study is the first demonstrating PO-DNA adducts in human individuals. It is also the first study indicating cytogenetic effects in humans from PO exposure, although confounding effects from other sources cannot be excluded.

Adult↗

Biopolymer-surfactant interaction: 4. Kinetics of binding of cetyltrimethyl ammonium bromide with gelatin, hemoglobin, beta-lactoglobulin and lysozyme.

The binding of CTAB with the proteins, gelatin, hemoglobin, beta-lactoglobulin and lysozyme follow first order kinetics and occurs either in two or three distinct stages. The number of stages depends on the overall configuration of the biopolymers. The denatured protein, gelatin has shown three-stage kinetics under all conditions, whereas the native proteins, hemoglobin, beta-lactoglobulin and lysozyme have exhibited two stage kinetics. Heat treated lysozyme in 8 mol dm-3 urea medium has also shown a two-stage kinetics. On the basis of non interacting binding sites on the proteins and independent sequential binding, the rates of reaction have been observed to increase with temperature and follow the trend k1 >> k2 > k3. The interaction of CTA+ with the proteins is both electrostatic and hydrophobic. Hemoglobin has shown maximum reaction rate whereas, beta-lactoglobulin has shown a minimum. The activation parameters for the kinetic process have exhibited almost non-variant delta G++ and delta H++ < T delta S++. The formation of activation complex in the Eyring model is entropy controlled so also the overall kinetics. An isokinetic entropy-enthalpy compensation phenomenon has been observed for the respective kinetic stages.

Biopolymers↗

Erythropoietin therapy in pre-dialysis patients with chronic renal failure: lack of need for parenteral iron.

BACKGROUND: During erythropoietin therapy, scant information exists regarding the optimal target percent saturation of transferrin (TSAT), ferritin and the mode and amount of iron supplementation in pre-dialysis patients with anemia due to chronic kidney disease (CKD). HYPOTHESIS: Pre-dialysis CKD patients may have different needs for iron supplementation than end-stage renal disease subjects during erythropoietin therapy. METHODS: Retrospective analysis of pre-dialysis CKD subjects (n = 31) treated with erythropoietin at our institution. RESULTS: In this population our results showed that target hematocrit (33-36%) was achievable with erythropoietin (mean subcutaneous dose 86 +/- 17 [SD] units/kg/week) without parenteral iron therapy. The hematocrit increased from a mean baseline value of 28.4 +/- 2.7 to 33.6 +/- 3.4% at time 1 (4-9 weeks, p < 0.0001), and to 37.7 +/- 4.5% at time 2 (10-20 weeks, p < 0.0001). The hemoglobin concentration increased from 9 +/- 0.9 g/dl at baseline to 10.7 +/- 1.1 g/dl at time 1 (p < 0.0001) and to 12 +/- 1.5 g/dl at time 2 (p < 0.0001). Subgroup analyses of patients prescribed <200 mg oral elemental iron per day (n = 10), those with TSAT <20% and/or ferritin <100 ng/ml (n = 19), and those prescribed erythropoietin <80 units/kg/week (n = 12), all showed a significant increase in hematocrit and hemoglobin. CONCLUSIONS: Our data show that pre-dialysis CKD subjects respond adequately to erythropoietin at or lower than recommended erythropoietin doses without parenteral iron. This response extends even to subgroups with TSAT and/or ferritin levels deemed to indicate iron deficiency in CKD subjects, and may be due to lack of existence of functional iron deficiency in this group of patients.

Aged↗

Evaluation of a program to overcome vitamin A and iron deficiencies in areas of poverty in Minas Gerais, Brazil.

Randon samples of children from both sexes from Belo Horizonte, the capital City, and from Turmalina, Jequitinhonha Valley, Minas Gerais, Brazil, were submitted to nutritional evaluation before and after the intervention "Program to Overcome Vitamin A and Iron Deficiencies in Areas of Poverty in Minas Gerais, Brazil". After the first examination, all the children received, with an interval of 180 days, a single oral dose of vitamin A, oral iron sulfate during 50 days, and 200 mg of Mebendazol/day for three days. Thirty days after ending administration of the third dose of medicine, the children were subjected to a new evaluation. In Belo Horizonte, the first evaluation revealed a high prevalence of deficient and low values of vitamin A in preschool children (21.5%) and school children (21.7%). A small prevalence of low hematocrit values was also observed in both groups. Deficient and low values of hemoglobin were found as well in 21.5% of preschool children and in 17.5% of school children. The second evaluation, practiced 30 days after the third dose of medicine, showed a small incidence of low vitamin A values (4.3% in preschool children and 2.9% in school children) and low hemoglobin values (6.5% in preschool children and 2.9% in school children). No deficient values of hemoglobin and vitamin A were observed. Concerning the hematocrit value, only one school child presented a low value at the second evaluation. On the other hand, in Jequitinhonha Valley, five cases of Bitot spot with conjunctival xerosis, two cases of corneal xerosis, and one case of keratomalacia were detected at the first examination. Thirty days after ending the third dose of medicine, only one corneal scar was observed. Only a small number of children with deficient and low levels of vitamin A and hemoglobin was found in the final evaluation (less than 8%), while this number was high at the first evaluation (above 38 and 12%, respectively). These results show the efficiency of the intervention Program in relation to hypovitaminosis A and iron anemia prevention. The Program is now being implemented by the Brazilian Ministry of Health.

Adolescent↗

The role of hemoglobin in the N-oxidation of 4-chloroaniline.

Rabbit hemoglobin effects reduced pyridine nucleotide-dependent N-oxidation of 4-chloroaniline in the presence of NADPH-cytochrome c (P-450) reductase (EC 1.6.2.4). The reaction is blocked by the addition of CO, superoxide dismutase (EC 1.15.1.1) and catalase (EC 1.11.1.6). The apparent Km value for the amine is 5.9 mM. The substrate interacts with hemoglobin in a non-cooperative manner; highly purified alpha- and beta-subunits mediate amine oxidation with kinetic constants close to those of the intact tetramer. Metabolism of 4-chloroaniline is associated with the formation of a 421 nm absorbing spectral complex, which might represent a ferryl species or a product adduct. Rapid reaction measurements suggests that either transfer of the second electron or product dissociation limits the overall rate of hemoglobin cycling. Erythrocyte reductases, such as 'NADPH-methemoglobin reductase' or soluble NADH-cytochrome b5 reductase (EC 1.6.2.2), also sustain amine oxidation in the presence of an appropriate electron carrier. Similarly, intact rabbit erythrocytes generate low amounts of N-oxy product when incubated with the parent amine. These findings support the notion that the red blood cell might be a site of bioactivation of aromatic amines, some of which, after being N-oxidized, become potent mutagens and carcinogens.

Aerobiosis↗

Iron bioavailability from fortified petit suisse cheese determined by the prophylactic-preventive method.

In this research, we measured the iron bioavailability of ferrous gluconate stabilized with glycine (SFG) when it is used to fortify petit suisse cheese using the prophylactic-preventive method in rats. Three groups of male, weaned rats received a basal diet (control diet; 5.2 ppm Fe), a reference standard diet (SO4Fe; 9.2 ppm Fe), and a basal diet using iron-fortified petit suisse cheese as the iron source (cheese diet; 8.8 ppm Fe) for 22 d. The iron bioavailability was calculated as the ratio between the mass of iron incorporated into hemoglobin and the total iron intake per animal during the treatment. These values (BioFe) were 68% and 72% for SFG and ferrous sulfate, respectively. The value of the Relative Biological Value (RBV) was 95% for SFG in petit suisse cheese. These results show that according to this method, the iron bioavailability from industrial fortified petit suisse cheese can be considered as a high bioavailability rate.

Analysis of Variance↗

Effect of supplemental lactoferrin with ferrous iron on iron status of newborn calves.

Data for 18 male and 18 female calves, born from primiparous and multiparous cows, were collected to determine the effect of supplemental lactoferrin and FeSO4 for 5 d after parturition on the Fe status of calves. Dietary treatments were 1) untreated, 2) 40 mg of Fe/d as FeSO4, and 3) 40 mg of Fe as FeSO4 plus 5 g of lactoferrin/d. Blood hematocrit and hemoglobin of calves born from primiparous cows at d 1 of age were lower than those of calves born from multiparous cows, but not different from those of their dams. Blood hematocrit and hemoglobin of male calves at d 1 of age were lower than those of female calves. Plasma Fe of primiparous cows at parturition was lower than that of multiparous cows, but plasma Fe of calves was not affected by parity of dam and sex of calf. Blood hematocrit and hemoglobin of untreated calves decreased from 1 to 10 d of age. Blood hematocrit and hemoglobin of calves treated with Fe of Fe plus lactoferrin increased from 2 to 10 d of age. Blood hematocrit and hemoglobin of calves treated with Fe plus lactoferrin were higher than those of calves treated with Fe at d 6 of age. Plasma Fe of calves treated with Fe or Fe plus lactoferrin increased temporarily at d 2 of age. Plasma Fe of calves treated with Fe plus lactoferrin at d 2 of age was lower than that of calves treated with Fe, but, at d 6 and 10 of age, plasma Fe of calves treated with Fe plus lactoferrin were higher.

Animals↗

Preliminary findings on iron supplementation and learning achievement of rural Indonesian children.

The effects of oral iron supplementation on blood iron levels and learning achievement in 130 rural Indonesian school children were assessed in this double-blind study. The children were classified into anemic and nonanemic groups according to their initial hemoglobin and transferrin saturation levels and were randomly assigned to either iron or placebo treatment for 3 mo. Hematological, anthropometric, and learning-achievement data were collected before (T1) and after (T2) the treatment period and 3 mo later. The means and standard deviations suggest that supplementation with 10 mg ferrous sulfate per kilogram body weight per day for 3 mo resulted in an apparent improvement in anemic subjects' hematological status and learning-achievement scores. No tests of statistical comparisons are reported.

Anemia, Hypochromic↗

A candidate reference method for determination of total protein in serum. I. Development and validation.

We developed a candidate Reference Method for measuring total serum protein by use of the biuret reaction. The method involves a previously described biuret reagent (Clin. Chem. 21: 1159, 1975) and Standard Reference Material (SRM) 927 bovine albumin (National Bureau of Standards) as the standard. At 25 degrees C, color development for 30 or 60 min provides identical serum protein values. Glucose (up to 10 g/L) and bilirubin (up to 300 mg/L) do not interfere. Hemoglobin, at 3 g/L, increases apparent serum protein by 0.4 g/L. The presence of dextran in serum causes easily detected turbidity, but this interference can be eliminated by centrifuging the reaction mixture. Therapeutic concentrations of ampicillin, carbenicillin, penicillin, oxacillin, nafcillin, chloramphenicol, cephalothin, and methicillin in blood do not interfere, nor do triglycerides up to 10 g/L. Within-run and day-to-day standard deviations of the method are 0.1 and 0.4 g/L, respectively.

Bilirubin↗

Bioavailability of iron in cooked egg yolk for maintenance of hemoglobin levels in growing rats.

The relative biological value (RBV) of iron in egg yolk was compared with that of iron in ferrous sulfate in prophylactic assays with weanling rats. Egg yolk cooked by one of three different methods was used in each experiment: (1) yolk of eggs boiled in the shell, lyophilized, and mixed with other dry diet ingredients; (2) pasteurized yolk and other diet components steamed with 8 liters of water per kilogram of diet; and (3) pasteurized yolk and other diet ingredients baked with 0.5 liters of water per kilogram of diet. Diets containing three levels of egg yolk and four levels of ferrous sulfate were fed to different groups of rats for 1, 2, and 3 weeks. Response of dietary iron was calculated as the regression of hemoglobin iron gain on iron intake and the nutritional quality of egg iron relative to that of ferrous sulfate iron was evaluated by slope-ratio analysis. RBV was 61, 64, and 90%, respectively, for iron of egg yolk cooked by the three methods. The presence of ascorbic acid during heat treatment of the diets significantly increased RBV of yolk iron from 64 to 92% in experiment 2, and increased it to a value equivalent to that of ferrous sulfate in experiment 3.

Animals↗

Implementing continuous quality improvement strategies for improving iron replacement in hemodialysis patients.

Anemia associated with end stage renal disease can diminish quality of life substantially. Maintaining a stable hematocrit and stable hemoglobin levels affords many advantages. Improvement of anemia management is possible with the implementation of continuous quality improvement (CQI). Our review of the literature motivated us to switch from iron dextran injection, which can induce anaphylactic reactions and has other associated problems, to sodium ferric gluconate complex injection. This enables us to safely provide iron supplementation without the precautions that were in place for iron dextran. Our methods for creating and implementing CQI in the dialysis program at our university hospital are described.

Algorithms↗

Correlation between functional and structural changes of reduced and oxidized trout hemoglobins I and IV at different pHs. A circular dichroism study.

Circular dichroism (CD) spectra of two major hemoglobin components (Hb), HbI and HbIV, from Oncorhyncus mykiss (formerly Salmo irideus) trout were evaluated in the range 250-600 nm. HbI is characterized by a complete insensitivity to pH changes, while HbIV presents the Root effect. Both reduced [iron(II) or oxy] and oxidized (met) forms of the two proteins were studied at different pHs, 7.8 and 6.0, to obtain information about the pH effects on the structural features of these hemoglobins. Data obtained show that oxy and met-HbI are almost insensitive to pH decrease, remaining in the R conformational state also at low pH. On the contrary, the pH decrease induces similar structural changes, characteristics of ligand dissociation and R-->T transition, both in the reduced and in the oxidized HbIV. The structural changes, monitored by CD, are compared with the peroxidative activity of iron(II)-Hb and met-Hb forms and with the superoxide anion scavenger capacity of the proteins.

Acridines↗

Effects of acute iron overload on Atlantic salmon (Salmo salar) and rainbow trout (Oncorhynchus mykiss).

Distribution of radioiron to various tissues after intraperitoneal injections was examined in Atlantic salmon and rainbow trout. Liver and spleen were found to be the major iron storage tissues. Injections of 1 or 5 mg iron as ferric ammonium citrate led to a fall in hemoglobin levels in both species after 2 d. Hemoglobin levels returned to normal levels in rainbow trout after 8 d, but Atlantic salmon had not recovered, and Hb levels fell below 3 g/100 mL. In both species, the fall in Hb was associated with a raise in iron levels in spleen and liver, suggesting damage to erythrocytes. Atlantic salmon liver ferritin showed a two- to threefold increase, while rainbow trout showed a sixfold increase, and a more rapid response. The toxic effect of iron in fish appears to be different from the effect in other vertebrates.

Animals↗

Impact of weekly treatment with ferrous sulfate on hemoglobin level, morbidity and nutritional status of anemic infants.

OBJECTIVE: To evaluate the impact of weekly treatment with ferrous sulfate on hemoglobin level, morbidity and nutritional status in a sample of anemic infants from Zona da Mata Meridional in the state of Pernambuco, Brazil. METHODS: A controlled, community-based intervention was carried out with 378 infants who were followed-up for 18 months. Hemoglobin level was measured at 12 months in a total of 245 children randomly selected. Participating infants were divided into three groups: two received 45 mg of elemental iron weekly, from 12 to 18 months of life (69 children with moderate/severe anemia, and 111 with mild anemia); the third group was composed of 65 non-anemic children, who received no intervention. The remaining 133 children constituted the control group, for comparisons on nutritional status and morbidity. RESULTS: The prevalence of anemia was 73.5% at 12 months of life. After 6 months of treatment, 42.3% of anemic children reached hemoglobin levels >or= 11.0 g/dL. The mean increase was 1.6 g/dL, being higher (2.5 g/dL) in the group with lower levels of hemoglobin at baseline. Children without anemia at baseline received no treatment, and 40.3% of them became anemic at the end of follow-up, with a mean decrease of 0.5 g/dL in hemoglobin levels. A significantly greater weight gain was observed in the two treated groups, while no significant improvements were seen in linear growth and duration of diarrhea. CONCLUSIONS: The fact that less than half the children receiving ferrous sulfate recovered from anemia at the end of follow-up, along with the development of anemia in many untreated, previously non-anemic infants, suggests the need for effective control strategies.

Anemia↗

A comparative study of the accurate measurement of endotoxin in liposome-encapsulated hemoglobin.

We have examined three different methods of endotoxin determination utilizing the Limulus Amebocyte Lysate (LAL) assay to accurately determine endotoxin levels in Liposome Encapsulated Hemoglobin (LEH), 1) the gel-clot method, 2) chromogenic spectroscopic-based LAL, and 3) the turbidimetric method which determines endotoxin levels in solutions based on the time needed to reach a specific degree of turbidity. Both the chromogenic and turbidimetric methods require significant dilution of the LEH preparation before accurate measurement can be made. We have tested the levels of endotoxin in LEH solutions using these methods and measured LEH, liposome, and hemoglobin samples spiked with known amounts of endotoxin. A comparison of the three methods shows that the absolute value of endotoxin measured in LEH by the three methods can vary significantly. However, within any one assay the spiked amount of endotoxin in the sample can be accurately measured. The accuracy of these methods may also be complicated by the binding of endotoxin to LEH. This was evident by mixing free endotoxin with LEH followed by centrifugation to separate the LEH. Biological activity of endotoxin bound to LEH was measured by exposure to RAW264.7 followed by the expression of tumor necrosis factor.

Chromogenic Compounds↗

Low temperature photodissociation studies of ferrous hemoglobin and myoglobin complexes by Mössbauer spectroscopy.

57Fe-enriched complexes of hemoglobin and myoglobin with CO and O2 were photodissociated at 4.2 degrees K, and the resulting spectra were compared with those of the deoxy forms. Differences in both quadrupole splitting and isomer shift were noted for each protein, the photoproducts having smaller isomer shift and larger quadrupole splitting than the deoxy forms. The photoproducts of HbCO and HbO2 had narrow absorption lines, indicating a well-defined iron environment. The corresponding myoglobin species had broader absorption lines, as did both deoxy forms. The weak absorption lines of photodissociated NO complexes appeared to be wide, possibly indicating magnetic interaction with the unpaired electron of the nearby NO.

Animals↗

The effect of metal chelators and other metabolic inhibitors on the growth of Bifidobacterium bifidus var. Pennsylvanicus.

Bifidobacterium bifidus var. Pennsylvanicus, a microaerophilic anaerobe, was grown in the presence of several potential growth inhibitors with the aim of defining its growth requirements and metabolic peculiarities. The following had no effect on its growth: citrate, serum transferrin, serum albumin, colchicine, fluoro-acetate, malonate, and rotenone. The following substances inhibited the growth: fluoride, azide, arsenite, 2, 4-dinitrophenol, hemin, hemoglobin, lactoferrin, alpha, alpha'-bipyridyl, and 8-hydroxyquinoline. Ferrous iron was able to negate the inhibition achieved by alpha, alpha'-bipyridyl, and 8-hydroxyquinoline. It is concluded that iron, probably in its ferrous state, is an obligatory nutrient for the microorganism, and that iron-porphyrin system(s) may be essential for the metabolism of this organism. Because the microorganisms contained in addition to iron large quantities of Mn, Zn, and Cu, it is likely that these metalloelements are crucial for the normal growth of the organism. Growth inhibition by fluoride indicates that Mg-dependent enzymes may also be present in the microorganism.

2,2'-Dipyridyl↗