Production hemoglobin

A marked interference with heme synthesis results in a reduction of the hemoglobin concentration in blood. Decreased hemoglobin production, coupled with an increase in erythrocyte destruction, results in a hypochromic, normocytic anemia with associated reticulocytosis. Decreased hemoglobin and anemia have been observed in lead workers and in children with prolonged exposure at higher PbB levels than those noted as threshold levels for inhibition or stimulation of enzyme activities involved in heme synthesis (EPA 1986a). 

M. A., Moore, J. W., Hydroxyurea-induced augmentation of fetal hemoglobin production in patients with sickle cell anemia, Blood 69 (1987), p. 109-116... 

Dover GJ, Brusilow S, Charache S (1994) Induction of fetal hemoglobin production in subjects with sickle cell anemia by oral sodium phenylbutyrate. Blood 84 339-343 El Kharroubi A, Martin MA (1996) cis-acting sequences located downstream of the human immunodeficiency virus type 1 promoter affect its chromatin structure and transcriptional activity. Mol Cell Biol 16 2958-2966... 

Pyridoxine (vitamin Be) is essential for protein metabolism and plays an important role in hemoglobin production. Pyridoxamine and pyri-doxal also possess vitamin Be activity. Sources of... 

Allergic contact dermatitis and even burns from prolonged skin contact with the cloves have been reported. Systemic allergy with bronchospasm or hives from ingestion occurs rarely. There is some concern that chronic high doses may lead to decreased hemoglobin production. 

The disease is caused by a mutation of a gene that controls hemoglobin production. A hemoglobin molecule consists of two types of amino acid chains alpha chains and beta chains. At the molecular level, the sickle-cell anemia mutation involves the replacement of one amino acid in the beta chains by another... 

The most common essential metal deficiency in the United States is that of iron. Iron-deficiency anemia is the result of inadequate iron availability, leading to decreased hemoglobin production. Clinically, this is recognized by smaller red blood cells with lower hemoglobin content than normal red blood cells. Other nutritional... 

Mithramycin is used as a DNA binding fluorescent dye, as an antineoplastic agent, and to reduce hypercalcemia, especially due to malignancies. Mithramycin is a potent inducer of fetal hemoglobin production in erythroid cells and is being... 

E. Liakopoulou, C. A. Blau, L. Qiliang, et al. Stimulation of fetal hemoglobin production by short chain fatty acids. Blood 86,3227 (1995). 

Susan Perrtne of the Children s Hospital Oakland Research Center decided to try to reawaken the dormant fetal globin gene. She and her colleagues injected a sodium butyrate solution (the sodium salt of butyric acid) into three sickle cell patients and three (3-thalassemia patients. As a result of the two- to three-week treatment, fetal hemoglobin production was boosted as much as 45% in these individuals. One (3-thalassemia patient even experienced a complete reversal of the symptoms. Moreover, this treatment had few adverse side effects. 

General measures Aikalinize urine by giving 5 to 15 6m. (75 gr. to 1/2 oz.) of sodium bicarbonate daily to prevent precipitation of hemoglobin or hemoglobin products in the kidneys. 

A mathematical model of the control system for erythropoiesis is presented. It is postulated that the rate of erythropoiesis is controlled by a hormone, erythropoietin, which is released from the kidney in response to reduced renal oxygen supply. Equations are developed relating erythropoietin release to arterial oxyhemoglobin concentration, and hemoglobin production to plasma erythropoietin concentration, with appropriate time delays. Effects of plasma volume changes during hypoxia are included. The model simulates the dynamic response of the erythropoietic system to a step decrease in the pOt of inspired air. Contributions of the parameters and relationships to the predicted response are analyzed. The model response compares favorably with experimental data obtained from mice subjected to different degrees of hypoxia. 

Figure 1. Block diagram of a model for the control of erythropoiesis (HbO), oxyhemoglobin concentration Vi, viscosity factor (HbO), effective oxyhemoglobin concentration R, rate of erythropoietin release (E), plasma erythropoietin concentration E0, normal plasma erythropoietin concentration V , distribution volume for erythropoietin P, rate of hemoglobin production MT, erythrocyte maturation time L, rate of hemoglobin loss TH, total circulating hemoglobin (Hb), blood hemoglobin concentration Vb, blood volume Vp, plasma volume Vp0, normal plasma volume Vpf, steady-state hypoxic plasma volume MCV, mean corpuscular volume MCH, mean corpuscular hemoglobin k, constant...

In the model, plasma erythropoietin concentration was used to determine the amount of hemoglobin produced and the time delay before new red blood cells (hemoglobin) are released into the blood stream. Equation 2 shows the postulated relationship between the rate of hemoglobin production and plasma erythropoietin concentration. 

P(t) = rate of hemoglobin production at time t Pm = maximum rate of hemoglobin production [E( t)] = plasma erythropoietin concentration at time t K3 and K4 are constants... 

The maximum rate of hemoglobin production is assumed to be seven times the normal production. The two constants, K3 and K4, were calculated using the conditions that (1) normal erythropoietin concentration results in normal hemoglobin production and (2) a basal hemoglobin production of. 005 gram/day occurs when erythropoietin concentration is zero. 

Although inclusion of the variable SCP allows an increased hemoglobin production following high plasma erythrpoietin concentrations,... 

With the relationship between oxyhemoglobin concentration and erythropoietin production selected to provide good agreement of erythropoietin concentration changes and experimental data, the constants in Equation 2 (hemoglobin production) were modified to produce a better total hemoglobin response. The conditions were that (1) normal plasma... 

Kosaka, H., Harada, N., Watanabe, M., Yoshihara, H., Katsuki, Y., and Shiga, T. (1992). Synergistic stimulation of nitric oxide hemoglobin production in rats by recombinant interleukin-1 and tumor necrosis factor. Biochem. Biophys. Res. Commun. 189,392-397. 

Regulation at the translational level and the role of informosomes. Many data indicate that regulation of gene expression takes place at the translational level in eukaryotic cells and that regulation of transcription is not the only mode of control of the kinds of proteins that are produced. Classic examples of translational control are the synthesis of such proteins as fibroin in the silk glands of the silkworm or hemoglobin production in reticulocytes. In both cases the synthesis of mRNA much precedes protein formation, and for a long period of time mRNA is accumulated without involvement in protein production. In fact, the peak of protein synthesis coincides with the period of depression of RNA production (Smirnov et al., 1964 see also review of Spirin, 1966). 

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