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T L Simon

Publications and source records attributed to T L Simon.

80 records · Page 5Linked to original sources
PubMedDate not supplied

Effects of AS-3 nutrient-additive solution on 42 and 49 days of storage of red cells.

Storage of red blood cells in a nutrient-additive solution, AS-3 (Nutricel, Cutter Biological, Berkeley, CA), was evaluated after 42 and 49 days of storage by in vitro measurements of hemolysis, adenosine triphosphate (ATP) levels, glucose levels and other constituents, and in vivo study of 24-hour survival of autologous, reinfused red cells labeled with 51Cr with and without 125I human serum albumin. Two laboratories conducted the studies independently. After 42 days of storage, hemolysis was within an acceptable range (0.72 +/- 0.4% and 1 +/- 0.2%), ATP decreased to 61 percent and 56 percent in the two laboratories, and 24-hour survivals were 85.1 +/- 8.3 percent for single-label cells in one laboratory and 82.8 +/- 10 percent (single-label cells) and 84.1 +/- 13.1 percent (double-label cells) in the second laboratory. Thus, results for single- and double-label cells were similar. After 49 days of storage, ATP fell to 45 and 46 percent in the two laboratories. Twenty-four-hour recovery fell to 69.4 +/- 7.4 percent with single-label cells and to 68.2 +/- 6.7 percent with double-label cells in one laboratory. In the other laboratory, a paired study comparing AS-3 with the already approved AS-1 solution (Adsol; Fenwal Laboratories, Deerfield, IL) showed nearly identical 24-hour survivals of 71.9 +/- 8.8 percent in Nutricel and 71.8 +/- 6.5 percent in Adsol. These studies demonstrate the excellent viability of the new solution after 42 days of study. At 49 days of study, viability decreased significantly and was comparable in the two nutrient-additive solutions studied. The value of paired comparison study is demonstrated by the latter results.

Blood Preservation↗
PubMedDate not supplied

Five-week red cell storage with preservation of 2,3 DPG.

The 2,3 diphosphoglycerate (2,3 DPG) content of red cells stored in current anticoagulant-preservative products decreases rapidly after the first few days of storage, and by 3 weeks the red cells are essentially depleted of 2,3 DPG. Because ascorbic acid and ascorbate-2-phosphate (A-2-P) are effective in maintaining erythrocyte 2,3 DPG during liquid preservation, ascorbate was stabilized through autoclaving and subsequent storage by adding it as the trisodium salt of A-2-P to a phosphate-adenine-saline solution at a pH of 8.5 to 9.0. Red cell concentrates prepared from blood drawn into citrate-phosphate-double-dextrose were supplemented with the A-2-P additive solution (AS-4) and studied in vitro and in vivo. Mean 2,3 DPG values for 22 units were 147.6, 113.5, and 82.3 percent of initial value after storage for 3, 4, and 5 weeks, respectively. Maintenance of 2,3 DPG was at the expense of adenosine triphosphate (ATP), which fell to as low as 22.2 percent of initial value after 5 weeks. Despite the low ATP values, the 24 hour 51Cr-labeled red cell recoveries averaged 80.8 and 74.1 percent after 4 and 5 weeks of storage, respectively. The AS-4 system provides a red cell product with acceptable viability and improved oxygen off-loading function.

2,3-Diphosphoglycerate↗
PubMedDate not supplied

Extended survival of neocytes produced by a new system.

Red cells (RBCs) prepared by a new system using centrifugation to produce neocyte enrichment were studied in two laboratories. The system used a blood bag with a geometric configuration such that younger, less dense cells could be separated from older, denser cells. Phthalate ester density gradient curves determined that neocyte enrichment was 81.3 percent in one laboratory and 82 percent in the other. RBC viability was studied by 51Cr autologous transfusion in normal volunteer donors. A randomized, paired design was used in which each donor was transfused once each with neocytes and with RBCs of all ages. The mean control half-life was 34.8 +/- 5.4 days in one laboratory and 34.0 +/- 3.6 days in the other. The mean half-life of the neocyte-enriched RBCs was 45.2 +/- 8.2 days in one laboratory and 45.1 +/- 4.4 days in the other. This represented a more than 30 percent increase in half-life for the neocyte-enriched RBCs, a significant difference. This new system, a two-bag set that costs +15, allows the simple, efficient separation of neocyte-enriched RBCs that would have a longer half-life and could reduce the transfusion requirement in patients receiving chronic transfusion therapy.

Blood Transfusion↗
PubMedDate not supplied

Preparation of white cell-depleted red cells for 42-day storage using an integral in-line filter.

A new blood pack system for the preparation of white cell-depleted red cells was studied. The system is a modified additive-solution quadruple-unit blood pack that incorporates a cellulose-acetate fiber depth filter in-line between the AS-3 additive bag and the CP2D collection bag. Mean +/- SD white cell removal from 156 units processed under standard production conditions was 97.7 +/- 2.7 percent; residual white cells were 1.1 +/- 1.0 x 10(8) per unit. Red cell loss was 10.0 +/- 1.0 percent (n = 43). Mean platelet removal was 80.9 percent from units from which platelet concentrates were not prepared (n = 47). Microaggregates did not form during storage, and hemolysis of filtered red cells was lower than that of unfiltered controls. Filtered AS-3 red cells stored for 42 days had a 51Cr survival of 80.1 +/- 5.7 percent (mean +/- SD) as compared with 78.9 +/- 6.2 percent for unfiltered controls (n = 17). This in-line filter system provides white cell-depleted, microaggregate-free red cells that can be stored for 42 days.

Adenosine Triphosphate↗
PubMedDate not supplied

The effects of red blood cell infusion on 10-km race time.

The purpose of this study was to investigate the effect of infusion of 400 mL of red blood cells (RBCs) on 10-km track race time, submaximal heart rate, hematocrit, 2,3-diphosphoglycerate, and partial pressure of oxygen at 50% hemoglobin saturation. Six highly trained, male, distance runners twice donated a unit of RBCs, which was frozen for subsequent reinfusion. Eleven weeks after the second donation, they undertook a series of three competitive 10-km races on a standard 400-m track: before infusion, after 100 mL of saline solution, and after 400 mL of autologous, previously frozen deglycerolized RBCs. All subjects took all trials in this double-blind, placebo, crossover, experimental design. Running time was recorded at each 400-m split, and blood was collected prior to each trial. The data were analyzed by analysis of variance. Results following the RBC infusion showed a significantly higher hematocrit concentration, a significantly faster 10-km run, a nonsignificant decrease in submaximal heart rate (10 beats faster 10-km run, a nonsignificant decrease in submaximal heart rate (10 beats per minute), and no significant changes in either 2,3-diphosphoglycerate or partial pressure of oxygen at 50% hemoglobin saturation. Erythrocythemia induced by the infusion of 400 mL of autologous packed RBCs effectively increased performance capacity in a 10-km track race, probably due to an increase in oxygen delivery to the working muscles.

2,3-Diphosphoglycerate↗
PubMedDate not supplied

Iron stores in blood donors.

A high frequency of donations by some blood donors has prompted concern about iron depletion. Five hundred sixteen female and 505 male donors were examined by measurements of hemoglobin, hematocrit, plasma iron, total iron-binding capacity, and ferritin values and detailed histories of iron ingestion, pregnancy and menstrual status, and past blood donations. Hemoglobin, hematocrit, and serum iron studies, unlike ferritin values, were not sensitive indicators of body iron depletion. Reduced iron stores were found in 8% of male and 23% of female donors. Menstruation significantly lowered iron stores in women. The total number of lifetime donations was not as predictive of decreased iron stores as frequency of donations per year. Even casual iron supplementation reduced the impact of donations on iron stores. Administration of iron to donors, especially menstruating women, should be studied by blood programs.

Anemia, Hypochromic↗