Analysis by Computer of some Oscillatory Features of the Red Cell System

1968 ◽  
pp. 227-233 ◽  
Author(s):  
J. Kirk ◽  
J. S. Orr
Keyword(s):  
Cell System ◽  
Red Cell

Synthesis of Artificial Models of Sickle Red Cells

1987 ◽  
Vol 110 ◽  
Author(s):  
Roderick D. Macgregor ◽  
Noel Taylor ◽  
Bertram Lubin ◽  
C. Anthony Hunt
Keyword(s):  
Lipid Bilayer ◽  
Bilayer Membrane ◽  
Cell System ◽  
Red Cells ◽  
Primary Role ◽  
Red Cell ◽  
Before And After ◽  
Synthetic Cells

AbstractThe primary role of a red cell substitute is to deliver oxygen to cells eitherin vivo or in vitro. It seems reasonable to mimic evolution, which solved the problem of oxygen delivery in many species by encapsulating oxygen carrying proteins in cell-sized delivery systems. We have successfully synthesized and tested an artificial red cell (Neohemocytes: see Science 230, 1165, 1985). How many properties or functions of red cells can one mimic synthetically? Can these synthetic cells serve as useful models? Here we report the first successful synthesis of an artificial model sickle cell. No reproducible, model cell system was previously available for research. A procedure identical to that used to prepare normal neohemocytes (NHC) was employed using sickle hemoglobin (HbS). The starting material was O2or CO liganded HbS at a concentration of approximately 15g% in a 30 mOsm phosphate buffer; this solution was kept ultrahypotonic until the final stage of the process. The lipid bilayer membrane was formed during a prolonged adjustment of the osmolality to 300 mOsm. The final step was removal of unencapsulated HbS. Sickle NHC were examined in parallel with normal (HbA containing) NHC by scanning and thin section electron microscopy before and after deoxygenation. These synthetic cells do sickle! Some look remarkably like red blood cells, only much smaller. Our data suggests that polymerization of the HbS within sickle NHC may be initiated by a different mechanism than the polymerization of purified solutions of HbS. The typical lipid bilayer seen in HbA containing NBC was essentially absent in the sickle NHC: similar results have been reported for irreversibly sickled red cells. Sickle NHC thus have remarkable potential to function as model sickle cells.

scholarly journals HEMOLYSIS OF CHICKEN BLOOD

1928 ◽  
Vol 12 (1) ◽  
pp. 17-28 ◽  
Author(s):  
G. Edgar Shattuck
Keyword(s):  
Sodium Oleate ◽  
Sodium Taurocholate ◽  
Cell System ◽  
Red Cell ◽  
End Point ◽  
Hemolytic Action ◽  
Chicken Erythrocytes ◽  
Chicken Blood ◽  
Time Dilution ◽  
Dilution Curves

1. The time-dilution curves are given for the hemolytic action of saponin, sodium taurocholate, and sodium oleate on nucleated chicken erythrocytes. 2. Saponin and sodium taurocholate cause hemolysis but leave the nuclei and ghosts in suspension, thereby making the end-point of hemolysis more arbitrary than the clear end-point for non-nucleated cell hemolysis. 3. The curves of hemolysis by saponin and taurocholate are shown to be of the same nature as are found in the hemolysis of non-nucleated cells. 4. Sodium oleate causes first hemolysis and then, in the stronger solutions, causes karyolysis. Two pairs of values for κ and c = ∞ are thus obtainable for the same reaction, one pair for the destruction of corpuscular membrane, the other pair for the destruction of the nucleus. 5. Viscosity changes are found in the lysin-cell system with strong concentrations of sodium taurocholate and sodium oleate. Time-viscosity curves are given for these changes. 6. Microscopically, the action of these lysins on the nucleated chicken red cell appears to be similar to their action on the non-nucleated erythrocytes.

THE EFFECT OF THYROXINE ON PERIPHERAL THYROID HORMONE METABOLISM

1969 ◽  
Vol 45 (3) ◽  
pp. 351-366
Author(s):  
A. W. G. GOOLDEN ◽  
JUNE M. GARTSIDE ◽  
C. OSORIO
Keyword(s):  
Thyroid Hormone ◽  
Cell System ◽  
Red Cells ◽  
Red Cell ◽  
Hormone Metabolism ◽  
Radioactive Product ◽  
Thyroid Hormone Metabolism ◽  
Normal People ◽  
Natural Metabolite

SUMMARY Blood samples obtained from normal people after an oral dose of 0·4 mg. l-thyroxine showed a depression in the uptake of [131I]tri-iodothyronine ([131I]T3) by the red cells, whereas the uptake by a resin sponge was increased. This depression did not occur when the test was carried out at 20° instead of at 37°. It was reversed when methylthiouracil, which is known to inhibit deiodination, was added to the blood in vitro. These findings are indicative of deiodination as the cause of the depression of T3-red cell (RBC) uptake. T3-RBC uptake was similarly depressed after the administration of l-tri-iodothyronine, and it was concluded that deiodination was promoted in the red cell system whenever there was an increase in the level of circulating thyroid hormone. The radioactive product of deiodination, which may be an artifact rather than a natural metabolite, has not been identified. Analysis of plasma obtained from blood after incubation with [131I]T3 under the conditions of the T3-RBC test, has not shown any [131I]iodide other than that present as an impurity in the [131I]T3 preparation. It could be shown that the product of deiodination is bound by the red cells but is eluted from them more readily than [131I]T3. It is suggested that the fall in T3-RBC uptake after thyroxine is due to deiodination which results in the formation of some radioactive product which is eluted from the red cells in the washing procedure.

N.m.r. studies of red cells

1980 ◽  
Vol 289 (1037) ◽  
pp. 395-406 ◽  
Keyword(s):  
Small Molecules ◽  
Time Course ◽  
Pulse Sequence ◽  
Spin Echo ◽  
Cell System ◽  
Red Cells ◽  
Red Cell ◽  
Lactate And Pyruvate ◽  
Echo Pulse ◽  
2,3 Dpg

Recent n.m.r. studies of intact red cells are described. With 1 H n.m.r. the normal high resolution spectra of red cells, even at high fields, are relatively uninformative because the very large number of resonances from the cells merge into a broad envelope. If a simple 90- τ - 180° spin echo pulse sequence is used, however, many resonances can be resolved. These include signals from haemoglobin histidines, glutathione, lactate and pyruvate. 13 C and 31 P signals have also been seen with a spectrometer converted to observe these nuclei essentially simultaneously. N.m.r. is well suited to monitor the time course of events after a perturbation of the cell system. Lactate increase, glutathione recovery after oxidation and alkylation of glutathione by iodoacetate can all be observed directly in red cell suspensions by means of 1 H spin echo n.m.r. This method has also been used to measure isotope exchange ( 1 H - 2 H) of lactate and of pyruvate at both the C-3 and the C-2 positions, and some of these exchange rates can be interpreted in terms of the activity of specific enzymes in the cells. 1 H spin echo n.m.r. has also been used to obtain information about the transport rates of small molecules into cells. By means of the 13 C / 31 P spectrometer and [ 13 C-1] glucose, the 13 C enrichment of 2,3-diphosphoglycerate (2,3-DPG) can be monitored at the same time as the levels of 2,3-DPG, ATP and inorganic phosphate are observed by 31 P n.m.r.

E Red Cell System in Pigs: Irregular Genetic Transmission

Vox Sanguinis ◽  
1971 ◽  
Vol 21 (1) ◽  
pp. 57-64
Author(s):  
L.N. Baker
Keyword(s):  
Cell System ◽  
Red Cell ◽  
Genetic Transmission

Ultrastructure of Choriocarcinoma in Vitro

1969 ◽  
Vol 27 ◽  
pp. 362-363
Author(s):  
John C. Garancis ◽  
R. A. Pattillo
Keyword(s):  
Cell Line ◽  
Physiological Function ◽  
Cell System ◽  
Bewo Cell ◽  
Bewo Cells ◽  
Gestational Choriocarcinoma ◽  
Bewo Cell Line

Growth of cell system (BeWo-cell line) derived from human gestational choriocarcinoma has been established and continuously maintained in-vitro. Furthermore, it is evident from the previous studies that this cell line has retained the physiological function of the placental trophoblasts, namely the synthesis of human chorionic gonadotrophil(HCG).The BeWo cells were relatively small and possessed single nuclei, thus indicating that this cell line consists exclusively of cytotrophoblasts. In some instances cells appeared widely separated and their lateral surfaces were provided with numerous microvilli (Fig.1).

The orientation of sickle hemoglobin fibers within fascicles

1988 ◽  
Vol 46 ◽  
pp. 400-401
Author(s):  
Christopher A. Miller ◽  
Bridget Carragher ◽  
William A. McDade ◽  
Robert Josephs
Keyword(s):  
Sickle Cell ◽  
Sickle Cell Anemia ◽  
Relative Orientation ◽  
Unit Cell ◽  
Red Cell ◽  
High Ph ◽  
Sickle Hemoglobin ◽  
Polar Crystal ◽  
Helical Configuration

Highly ordered bundles of deoxyhemoglobin S (HbS) fibers, termed fascicles, are intermediates in the high pH crystallization pathway of HbS. These fibers consist of 7 Wishner-Love double strands in a helical configuration. Since each double strand has a polarity, the odd number of double strands in the fiber imparts a net polarity to the structure. HbS crystals have a unit cell containing two double strands, one of each polarity, resulting in a net polarity of zero. Therefore a rearrangement of the double strands must occur to form a non-polar crystal from the polar fibers. To determine the role of fascicles as an intermediate in the crystallization pathway it is important to understand the relative orientation of fibers within fascicles. Furthermore, an understanding of fascicle structure may have implications for the design of potential sickling inhibitors, since it is bundles of fibers which cause the red cell distortion responsible for the vaso-occlusive complications characteristic of sickle cell anemia.

Erythrophagocytosis in the Liver in Hemolytic Anemias

1968 ◽  
Vol 26 ◽  
pp. 184-185
Author(s):  
O. T. Minick ◽  
E. Orfei ◽  
F. Volini ◽  
G. Kent
Keyword(s):  
Acid Phosphatase ◽  
Oxidative Damage ◽  
Phosphatase Activity ◽  
Kupffer Cells ◽  
Acid Phosphatase Activity ◽  
Common Type ◽  
Red Cell ◽  
Cell Fragments ◽  
Reticulo Endothelial System ◽  
Important Site

Hemolytic anemias were produced in rats by administering phenylhydrazine or anti-erythrocytic (rooster) serum, the latter having agglutinin and hemolysin titers exceeding 1:1000.Following administration of phenylhydrazine, the erythrocytes undergo oxidative damage and are removed from the circulation by the cells of the reticulo-endothelial system, predominantly by the spleen. With increasing dosage or if animals are splenectomized, the Kupffer cells become an important site of sequestration and are greatly hypertrophied. Whole red cells are the most common type engulfed; they are broken down in digestive vacuoles, as shown by the presence of acid phosphatase activity (Fig. 1). Heinz body material and membranes persist longer than native hemoglobin. With larger doses of phenylhydrazine, erythrocytes undergo intravascular fragmentation, and the particles phagocytized are now mainly red cell fragments of varying sizes (Fig. 2).

Pure red cell aplasia

2000 ◽  
Vol 111 (4) ◽  
pp. 1010-1022 ◽  
Author(s):  
Paul Fisch ◽  
Rupert Handgretinger ◽  
Hans-Eckart Schaefer
Keyword(s):  
Pure Red Cell Aplasia ◽  
Red Cell ◽  
Red Cell Aplasia
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