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G E CARTWRIGHT

Publications and source records attributed to G E CARTWRIGHT.

At least 73 records · Page 4Linked to original sources
PubMed1956

Studies on copper metabolism. XIX. The kinetics of iron metabolism and erythrocyte life-span in copper-deficient swine.

Ferrokinetic studies were performed in three copper-deficient swine and the results have been compared with similar studies in 18 normal pigs. The mean value for the plasma iron turnover rate in the deficient swine was 1.76 mg./kg. day; for the red cell iron incorporation rate, 1.24 mg./kg. day; for the red cell iron turnover rate, 1.18 mg./kg. day; for the red cell life span, 13 days. Corresponding figures in the normal swine were 1.11 mg./kg. day, 1.01 mg./kg. day, 0.59 mg./kg. day and 63 days, respectively. The red cell life span was measured by the use of radioactive chromium in a total of 26 pigs. The mean erythrocyte half-life of normal cells transfused into normal pigs was 17 days. The mean half-life of erythrocytes from copperdeficient swine transfused into copper-deficient swine was 9 days. The mean half-life of red cells from control animals transfused into copper-deficient swine was 16 days while that of erythrocytes from copper-deficient swine transfused into normal pigs, was 13 days. The mean half-life of cells from iron-deficient pigs transfused into iron-deficient pigs was 19 days. It is concluded that copper deficiency anemia results from both a shortened erythrocyte survival time and limited capacity of the bone marrow to produce red cells. It is suggested that copper is an essential component of erythrocytes in swine.

Anemia↗
PubMed1956

The kinetics of iron metabolism in normal growing swine.

Plasma and red cell iron turnover rates were determined in 18 normal growing swine by the use of tracer doses of Fe(59). Body surface counting was performed on a representative group of animals following the injection of the isotope. The mean half-time of plasma iron disappearance was 1.19 +/- 0.26 hours. Two exponential rates of disappearance of Fe(59) from the plasma were observed in 15 of the pigs and a single rate was observed in the other 3. The mean plasma iron turnover rate was 1.11 +/- 0.34 mg./kg. day. The average maximum incorporation of Fe(59) into the erythrocytes was 92 +/- 9 per cent. The mean red cell iron incorporation rate was 1.10 mg./kg. day, but an average of 0.42 mg./kg. day of this was calculated as being due to increasing red cell mass incidental to body growth, so that the true mean red cell iron turnover rate was 0.59 +/- 0.19 mg./kg. day. The average "apparent" red cell life span was 63 +/- 16 days. This is in agreement with the red cell life span of 62 days determined previously with glycine-2-C(14).

Animals↗
PubMed1956

The kinetics of iron metabolism in swine with various experimentally induced anemias.

Ferrokinetic studies were performed on 3 swine given phenylhydrazine, 3 swine deficient in pyridoxine, and 3 swine deficient in pteroylglutamic acid. Body surface radioactivity was measured in 2 pteroylglutamic acid-deficient animals. In the animals given phenylhydrazine, the mean erythrocyte survival time was 5 days. The plasma iron turnover rate was increased about fourfold, and the rate of erythropoiesis was four to five times greater than that in the control pigs. In the pyridoxine-deficient swine, the mean erythrocyte survival time was within the limits of normal. The plasma iron turnover rate was increased fourfold, but the rate of erythropoiesis was approximately one-fourth the normal mean value. These data are interpreted as indicating that the anemia associated with this deficiency is a result of an inability of the bone marrow to produce a normal number of erythrocytes. In the pteroylglutamic acid-deficient swine, the mean erythrocyte survival time was 17 days. The plasma iron turnover rate was 5 times the normal mean value. The rate of erythropoiesis was 1.6 times greater than the mean value in the control pigs. These data are interpreted as indicating that anemia develops in this deficiency as a result of a combination of a shortening of the erythrocyte survival time and a limitation of the capacity of the bone marrow to increase red cell production to the same degree as a normal marrow. The radioactivity in the liver, spleen, and bone marrow of the pteroylglutamic acid-deficient swine, as determined by measurement of the radioactivity over the body surface, declined more slowly than in control pigs.

Anemia↗
PubMed1955

Erythrocyte life span in growing swine as determined by glycine-2-C14.

Red blood cell survival studies were performed on five normal growing swine by following the C(14)-specific activity of hemoglobin and heme after the administration of glycine-2-C(14). The erythrocytes of normal growing swine appear to be destroyed both by a random and an age-dependent process. Random destruction accounts for the larger portion of the cells which are destroyed. The "mean" red cell survival time was 62 days. This represents the interval from the time of incorporation of 50 per cent of the maximal amount of labelling achieved to the time when the level had decreased once more to the 50 per cent amount. The " 'corrected' average potential life span" of the red cells was 86 +/- 11.5 days. This figure was obtained by subtracting the number of days required to attain 80 per cent of the maximal labelling from the average survival time of red cells destroyed by an age-dependent process as distinguished from random destruction.

Animals↗