Red cell effect

The three principal conclusions emerging from this study are that (1) the red cell effect can now be further generalized to include glass surface (2) a considerable difference in competitive adsorption exists between oxyhemoglobin and methemoglobin and (3) inhibition of adsorption by red cells appears to be a cell membrane-related effect. 

The results with ghost cells suggest that the membranes play a key role in the red cell effect. This point of view is in accord with conclusions from... 

Surface Tension. Interfacial surface tension between fluid and filter media is considered to play a role in the adhesion of blood cells to synthetic fibers. Interfacial tension is a result of the interaction between the surface tension of the fluid and the filter media. Direct experimental evidence has shown that varying this interfacial tension influences the adhesion of blood cells to biomaterials. The viscosity of the blood product is important in the shear forces of the fluid to the attached cells viscosity of a red cell concentrate is at least 500 times that of a platelet concentrate. This has a considerable effect on the shear and flow rates through the filter. The surface stickiness plays a role in the critical shear force for detachment of adhered blood cells. 

The influence of pH on the affinity of Hb for oxygen known as the Bohr-effect indicates that protons retain the allosteric regulation of oxygen transport. It is also an indirect confirmation of the ability of Hb and Im Hb for transporting carbon dioxide. The values of the Bohr-effect d log P50/d pH for Hb and Im Hb are close to each other in the pH range 7.1-7.4. It is possible that the effect of the micro-environment of carboxylic CP on immobilized Hb and its polyfunctional interaction represents the interaction between Hb and the structural elements inside the red cell [99]. 

If we combine the data on survival of red cells vs. temperatiue in Figure 10 with the data in Figure 12 on the effect of temperature on the unfrozen fraction, we obtain the results shown in Figure 1 IB. The curves are mirror images of those in Figure 11A which relate survival to salt concentration. They show that survival drops from above 80% when the unfrozen water fraction is 0.14 or more, to below 20% when... 

Hydroxyurea is a ribonucleotide reductase inhibitor that prevents DNA synthesis and traditionally has been used in chemotherapy regimens. Studies in the 1990s also found that hydroxyurea increases HbF levels as well as increasing the number of HbF-containing reticulocytes and intracellular HbF. Other beneficial effects of hydroxyurea include antioxidant properties, reduction of neutrophils and monocytes, increased intracellular water content leading to increased red cell deformability, decreased red cell adhesion to endothelium, and increased levels of nitric oxide, which is a regulator involved in physiologic disturbances.22... 

In humans, severe cases of acrylonitrile poisoning have resulted in low grade anemia (Wilson 1944 Wilson et al. 1948), but complete recovery was reported. Chronic occupational exposure to low levels of acrylonitrile has not resulted in detectable effects on the hematological system (Sakurai et al. 1978). In intermediate and chronic studies in animals, decreased red cell count, hemoglobin concentration and hematocyte were observed (Bio/dynamics 1980a, 1980b, 1980c Quast et al. 

Farooqui MYFI, Ahmed AE. 1983a. The effects of acrylonitrile on hemoglobin and red cell metabolism. J Toxicol Environ Health 12 695-707. 

Mentzer Jr., W.C., and Lubin, B.H. (1979) The effect of cross-linking agents on red-cell shape. Semin. Hematol. 16, 115-127. 

An endemic zinc deficiency syndrome among young men has been reported from Iran and Egypt, and is characterized by retarded growth, infantile testes, delayed sexual maturation, mental lethargy, anemia, reduced concentration of zinc in plasma and red cells, enlarged liver and spleen, and hyperpigmentation oral supplementation of 30 mg Zn daily had a prompt beneficial effect (Prasad 1979 Elinder 1986). 

There were no effects on the red blood cell counts of dogs exposed to 0, 15, 48, or 260 ppm hexachloroethane for 6 weeks (Weeks et al. 1979). Although other hematological parameters were apparently determined, the red cell count was the only parameter that was specified. Accordingly, it is not possible to speculate whether inhalation exposure to hexachloroethane has any effect on other hematological parameters. 

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