The introduction of a 7.5% hypertonic saline/6% dextran 70 (HSD) solution into clinical trials for the treatment of hypovolemic states, and the past concerns regarding the possible interference of dextran with blood serology, prompted us to investigate the effects of HSD on human red-cell typing and stability. HSD was evaluated with fresh and 35-day stored CPDA-1 red cells from 12 healthy donors. A 1:5 mixture of HSD to blood in vitro had no effect on ABO, Rh, and MN typing in both fresh and stored blood. HSD produced no significant lysis with fresh cells and a minimal level with stored blood. No evidence of metabolic or morphologic changes was seen after HSD treatment. The results of this study suggest that the clinical use of HSD for the treatment of hemorrhagic shock will not affect blood group determinations or red-cell stability from stored blood which may be infused after the HSD-treated patient is transported to a hospital.

Pyridoxylated adult human hemoglobin (HbAo) was prepared using a one molar equivalent of pyridoxal 5‐phosphate (PLP) per heme and reduced with either NaCNBH 3 or NaBH 4 . A separate sample was pyridoxylated and passed through a mixed‐bed ion exchange column without reduction. All three preparations had a P 50 of 29 ± 2 torr and a cooperativity of n = 2.4 ± 0.1. These preparations, in both the oxy and deoxy forms, were then treated with 7 equivalents of glutaraldehyde per tetramer at pH 6.8 at 4°C and at room temperature. The polymerization invariably reduced the P 50 to 18 ± 2 torr with Hill coefficients of less than 2. These solutions, with or without further reduction using NaCNBH 3 , all retained the PLP in differing amounts (2–3 moles/tetramer). Methemoglobin concentrations were increased during the polymerization reaction. The normal pyridoxylation procedure, using sodium borohydride reduction, resulted in a number of different molecular species. Polymerization with glutaraldehyde caused a further proliferation of molecular species that could not be separated by anion exchange chromatography or by isoelectric focusing. The extent of polymerization, estimated by gel exclusion chromatography and SDS polyacrylamide gel electrophoresis, was from 40 to 50%. Analysis of the reverse phase chromatograms, which separate the heme and the α‐ and β‐chains, showed extensive polymerization and distribution of the radioactively labeled PLP on the protein for all preparations. All of the polymerized and pyridoxylated samples were unstable, and showed different chromatographic patterns after storage at 4°C for 1 month. Attempts to stabilize these preparations by further reduction with NaCNBH 3 gave products with a lower P 50 and lower cooperativity. When the reactions were conducted with a purified HbAo, heterogeneity was somewhat decreased compared to the normally used stroma‐free hemoglobin, but a large number of molecular species were still formed.

Twenty-one moss species new to Montana are reported and their distribution patterns in North America are noted. The moss flora of Montana, although not com- prehensively studied, has been reported by Evers- man and Sharp (1980) to include 328 species dis- tributed among 116 genera and 40 families. Most of the data presented by these authors are for col- lections from the western, mountainous portions of the state.

Pyridoxylated normal adult human hemoglobin (HbAo) has been prepared using both oxygenated and deoxygenated HbAo at pH 6.8 and room temperature without the addition of Tris to produce a mixture with P50 of 30 +/- 2 torr and a Hill coefficient of 2.3 +/- 0.1 similar to that of the isolated adult human hemoglobin from the red blood cell. Reduction of the pyridoxylated HbAo in the oxygen-ligated form by sodium borohydride gives unacceptable levels of methemoglobin (i.e., greater than 10%). Excessive foaming and methemoglobin formation can be partially avoided using deoxyHbAo. Reduction with sodium cyanoborohydride is much gentler and gives solutions with less than 5% methemoglobin. Both reducing agents give products with multiple components as shown by analytical chromatography. Radioautography on the isoelectric focusing gels of HbAo treated with 14C pyridoxal 5-phosphate (PLP) shows three major bands for the cyanoborohydride-reduced derivatives and a much more complex mixture of labeled molecules after the sodium borohydride reduction. When pyridoxylated hemoglobin is prepared without reduction, the preparation, after passage through a mixed-bed resin, contains 0.4 equivalents of PLP per heme, and has a P50 of 30 +/- 2 torr and an n value of 2.3 similar to the values found after reduction. Upon anion exchange resin chromatography, the PLP is removed, indicating that the reaction forms a reversible Schiff base. On standing at 4 degrees C for one month, this preparation produces a mixture of HbAo and pyridoxylated HbAo with the original P50. Methemoglobin increased to 3% during this incubation. After four months in the cold, the yield of a single chromatographic species is 70% with 20% methemoglobin. This fraction appears to be stable and can be passed through an anion exchange column without release of the PLP. Separation of the individual chains by reverse-phase chromatography indicates that the addition of PLP to HbAo is directed solely to the beta-chains. This is also the case for the cyanoborohydride reduced derivatives. When NaBH4 is used for the reduction, radioactively labeled PLP is found on both the alpha- and beta-chains.

For several decades the standard blood preservative solution consisted of citrate, dextrose, and, later, phosphate (ACD and CPD). In 1978 a new solution containing adenine (CPDA-1) was introduced to permit extension of red cell shelf life from 21 to 35 days. The success of CPDA-1 and the high percentage of blood units processed into components (estimated 87% in 1983) have stimulated a burst of research and development activity to develop improved red cell preservation systems. Most of these systems have taken the form of "additive solutions" in which the blood is drawn in CPD or CP2D and processed into components. Then the packed red cells are stored by addition of a solution customized for their preservation. This review evaluates these additive solutions in detail. Innovative systems for pH control (buffers and resins) have also been explored. Our review concludes with discussion of the safety aspects of new preservative solutions and the methodological problems of evaluating these solutions.

The recent Food and Drug Administration (U.S.) approval of a new blood preservative (CPDA-1) which contains adenine not only introduces a new blood product into the American blood banking system, but also heralds the advent of novel approaches to blood product preservation. The use of adenine to effect maintenance of red cell adenosine triphosphate (ATP), and hence to prolong storability, has a well-founded biochemical rationale. Effects of adenine on red cell metabolism are generally well understood, but effects on other blood components have not been fully delineated. The efficacy of adenine preservatives in enhancing the duration of red cell storage appears to outweigh the small risk of toxicity from free adenine. Clinical use of millions of units of adenine-preserved blood in Europe during more than a decade has resulted in only one report of possible adenine toxicity. Marginal acceptability of 24-hr 51Cr red cell recovery of packed red cells stored for 35 days in CPDA-1 has stimulated development and evaluation of an improved preservative (CPDA-2) which may extend blood storability beyond 35 days. A heightened awareness of the hematological consequences of prolonged storage has come with the extension of blood storage beyond 21 days. The concepts of component-specific preservation systems and optimal preservation systems have emerged as a result of experimentation on adenine preservatives. While the influence of adenine preservatives on American blood banking is yet to become manifest, the ultimte impact of adenine on blood preservation may be the development of novel systems which optimally preserve specific blood components at the option of the user.

Red cells were stored for 42 days, with and without added progesterone, and at 14-day intervals stroma was prepared from these red cells for analysis by various physicochemical methods. Progesterone appears to bind to the erythrocyte membrane proteins, causing a change in their structure which “locks” them into a stabilized state that is more or less constant for at least 28 days, then starts to wear off or dissociate.

A method is described for the separation of dansyl amino acids on Whatman 3MM paper using electrophoresis at pH 4.4, followed by descending chromatography employing two different solvent systems.